Correct monero-serai for aggressive clippy

Parallelized. Doesn't check the deserialization is correct. Does use distinct,
persistent HTTP clients.

.gitattributes

@@ -0,0 +1,5 @@
+# Auto detect text files and perform LF normalization
+* text=auto
+* text eol=lf
+
+*.pdf binary

.github/actions/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022-2023 Luke Parker
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

.github/actions/bitcoin/action.yml

@@ -0,0 +1,47 @@
+name: bitcoin-regtest
+description: Spawns a regtest Bitcoin daemon
+
+inputs:
+  version:
+    description: "Version to download and run"
+    required: false
+    default: 24.0.1
+
+runs:
+  using: "composite"
+  steps:
+    - name: Bitcoin Daemon Cache
+      id: cache-bitcoind
+      uses: actions/cache@v3
+      with:
+        path: bitcoin.tar.gz
+        key: bitcoind-${{ runner.os }}-${{ runner.arch }}-${{ inputs.version }}
+
+    - name: Download the Bitcoin Daemon
+      if: steps.cache-bitcoind.outputs.cache-hit != 'true'
+      shell: bash
+      run: |
+        RUNNER_OS=linux
+        RUNNER_ARCH=x86_64
+        FILE=bitcoin-${{ inputs.version }}-$RUNNER_ARCH-$RUNNER_OS-gnu.tar.gz
+
+        wget https://bitcoincore.org/bin/bitcoin-core-${{ inputs.version }}/$FILE
+        mv $FILE bitcoin.tar.gz
+
+    - name: Extract the Bitcoin Daemon
+      shell: bash
+      run: |
+        tar xzvf bitcoin.tar.gz
+        cd bitcoin-${{ inputs.version }}
+        sudo mv bin/* /bin && sudo mv lib/* /lib
+
+    - name: Bitcoin Regtest Daemon
+      shell: bash
+      run: |
+        RPC_USER=serai
+        RPC_PASS=seraidex
+
+        bitcoind -txindex -regtest \
+          -rpcuser=$RPC_USER -rpcpassword=$RPC_PASS \
+          -rpcbind=127.0.0.1 -rpcbind=$(hostname) -rpcallowip=0.0.0.0/0 \
+          -daemon

.github/actions/build-dependencies/action.yml

@@ -0,0 +1,43 @@
+name: build-dependencies
+description: Installs build dependencies for Serai
+
+inputs:
+  github-token:
+    description: "GitHub token to install Protobuf with"
+    require: true
+    default:
+
+  rust-toolchain:
+    description: "Rust toolchain to install"
+    required: false
+    default: stable
+
+  rust-components:
+    description: "Rust components to install"
+    required: false
+    default:
+
+runs:
+  using: "composite"
+  steps:
+    - name: Install Protobuf
+      uses: arduino/setup-protoc@v2.0.0
+      with:
+        repo-token: ${{ inputs.github-token }}
+
+    - name: Install solc
+      shell: bash
+      run: |
+        pip3 install solc-select==0.2.1
+        solc-select install 0.8.16
+        solc-select use 0.8.16
+
+    - name: Install Rust
+      uses: dtolnay/rust-toolchain@master
+      with:
+        toolchain: ${{ inputs.rust-toolchain }}
+        components: ${{ inputs.rust-components }}
+        targets: wasm32-unknown-unknown, riscv32imac-unknown-none-elf
+
+    # - name: Cache Rust
+    #   uses: Swatinem/rust-cache@v2

.github/actions/monero-wallet-rpc/action.yml

@@ -0,0 +1,44 @@
+name: monero-wallet-rpc
+description: Spawns a Monero Wallet-RPC.
+
+inputs:
+  version:
+    description: "Version to download and run"
+    required: false
+    default: v0.18.2.0
+
+runs:
+  using: "composite"
+  steps:
+    - name: Monero Wallet RPC Cache
+      id: cache-monero-wallet-rpc
+      uses: actions/cache@v3
+      with:
+        path: monero-wallet-rpc
+        key: monero-wallet-rpc-${{ runner.os }}-${{ runner.arch }}-${{ inputs.version }}
+
+    - name: Download the Monero Wallet RPC
+      if: steps.cache-monero-wallet-rpc.outputs.cache-hit != 'true'
+      # Calculates OS/ARCH to demonstrate it, yet then locks to linux-x64 due
+      # to the contained folder not following the same naming scheme and
+      # requiring further expansion not worth doing right now
+      shell: bash
+      run: |
+        RUNNER_OS=${{ runner.os }}
+        RUNNER_ARCH=${{ runner.arch }}
+
+        RUNNER_OS=${RUNNER_OS,,}
+        RUNNER_ARCH=${RUNNER_ARCH,,}
+
+        RUNNER_OS=linux
+        RUNNER_ARCH=x64
+
+        FILE=monero-$RUNNER_OS-$RUNNER_ARCH-${{ inputs.version }}.tar.bz2
+        wget https://downloads.getmonero.org/cli/$FILE
+        tar -xvf $FILE
+
+        mv monero-x86_64-linux-gnu-${{ inputs.version }}/monero-wallet-rpc monero-wallet-rpc
+
+    - name: Monero Wallet RPC
+      shell: bash
+      run: ./monero-wallet-rpc --disable-rpc-login --rpc-bind-port 6061 --allow-mismatched-daemon-version --wallet-dir ./ --detach

.github/actions/monero/action.yml

@@ -0,0 +1,44 @@
+name: monero-regtest
+description: Spawns a regtest Monero daemon
+
+inputs:
+  version:
+    description: "Version to download and run"
+    required: false
+    default: v0.18.2.0
+
+runs:
+  using: "composite"
+  steps:
+    - name: Monero Daemon Cache
+      id: cache-monerod
+      uses: actions/cache@v3
+      with:
+        path: monerod
+        key: monerod-${{ runner.os }}-${{ runner.arch }}-${{ inputs.version }}
+
+    - name: Download the Monero Daemon
+      if: steps.cache-monerod.outputs.cache-hit != 'true'
+      # Calculates OS/ARCH to demonstrate it, yet then locks to linux-x64 due
+      # to the contained folder not following the same naming scheme and
+      # requiring further expansion not worth doing right now
+      shell: bash
+      run: |
+        RUNNER_OS=${{ runner.os }}
+        RUNNER_ARCH=${{ runner.arch }}
+
+        RUNNER_OS=${RUNNER_OS,,}
+        RUNNER_ARCH=${RUNNER_ARCH,,}
+
+        RUNNER_OS=linux
+        RUNNER_ARCH=x64
+
+        FILE=monero-$RUNNER_OS-$RUNNER_ARCH-${{ inputs.version }}.tar.bz2
+        wget https://downloads.getmonero.org/cli/$FILE
+        tar -xvf $FILE
+
+        mv monero-x86_64-linux-gnu-${{ inputs.version }}/monerod monerod
+
+    - name: Monero Regtest Daemon
+      shell: bash
+      run: ./monerod --regtest --offline --fixed-difficulty=1 --detach

.github/actions/test-dependencies/action.yml

@@ -0,0 +1,44 @@
+name: test-dependencies
+description: Installs test dependencies for Serai
+
+inputs:
+  github-token:
+    description: "GitHub token to install Protobuf with"
+    require: true
+    default:
+
+  monero-version:
+    description: "Monero version to download and run as a regtest node"
+    required: false
+    default: v0.18.2.0
+
+  bitcoin-version:
+    description: "Bitcoin version to download and run as a regtest node"
+    required: false
+    default: 24.0.1
+
+runs:
+  using: "composite"
+  steps:
+    - name: Install Build Dependencies
+      uses: ./.github/actions/build-dependencies
+      with:
+        github-token: ${{ inputs.github-token }}
+
+    - name: Install Foundry
+      uses: foundry-rs/foundry-toolchain@v1
+      with:
+        version: nightly
+
+    - name: Run a Monero Regtest Node
+      uses: ./.github/actions/monero
+      with:
+        version: ${{ inputs.monero-version }}
+
+    - name: Run a Bitcoin Regtest Node
+      uses: ./.github/actions/bitcoin
+      with:
+        version: ${{ inputs.bitcoin-version }}
+
+    - name: Run a Monero Wallet-RPC
+      uses: ./.github/actions/monero-wallet-rpc

.github/nightly-version

@@ -0,0 +1 @@
+nightly-2023-07-01

.github/workflows/daily-deny.yml

@@ -0,0 +1,27 @@
+name: Daily Deny Check
+
+on:
+  schedule:
+    - cron: "0 0 * * *"
+
+jobs:
+  deny:
+    name: Run cargo deny
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Advisory Cache
+        uses: actions/cache@v3
+        with:
+          path: ~/.cargo/advisory-db
+          key: rust-advisory-db
+
+      - name: Install cargo
+        uses: dtolnay/rust-toolchain@stable
+
+      - name: Install cargo deny
+        run: cargo install --locked cargo-deny
+
+      - name: Run cargo deny
+        run: cargo deny -L error --all-features check

.github/workflows/monero-tests.yaml

@@ -0,0 +1,59 @@
+name: Monero Tests
+
+on:
+  push:
+    branches:
+      - develop
+    paths:
+      - "coins/monero/**"
+      - "processor/**"
+
+  pull_request:
+    paths:
+      - "coins/monero/**"
+      - "processor/**"
+
+jobs:
+  # Only run these once since they will be consistent regardless of any node
+  unit-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Test Dependencies
+        uses: ./.github/actions/test-dependencies
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Run Unit Tests Without Features
+        run: cargo test --package monero-serai --lib
+
+      # Doesn't run unit tests with features as the tests workflow will
+
+  integration-tests:
+    runs-on: ubuntu-latest
+    # Test against all supported protocol versions
+    strategy:
+      matrix:
+        version: [v0.17.3.2, v0.18.2.0]
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Test Dependencies
+        uses: ./.github/actions/test-dependencies
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          monero-version: ${{ matrix.version }}
+
+      - name: Run Integration Tests Without Features
+        # Runs with the binaries feature so the binaries build
+        # https://github.com/rust-lang/cargo/issues/8396
+        run: cargo test --package monero-serai --features binaries --test '*'
+
+      - name: Run Integration Tests
+        # Don't run if the the tests workflow also will
+        if: ${{ matrix.version != 'v0.18.2.0' }}
+        run: |
+          cargo test --package monero-serai --all-features --test '*'
+          cargo test --package serai-processor --all-features monero

.github/workflows/monthly-nightly-update.yml

@@ -0,0 +1,53 @@
+name: Monthly Nightly Update
+
+on:
+  schedule:
+    - cron: "0 0 1 * *"
+
+jobs:
+  update:
+    name: Update nightly
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: "recursive"
+
+      - name: Write nightly version
+        run: echo $(date +"nightly-%Y-%m"-01) > .github/nightly-version
+
+      - name: Create the commit
+        run: |
+          git config user.name "GitHub Actions"
+          git config user.email "<>"
+
+          git checkout -b $(date +"nightly-%Y-%m")
+
+          git add .github/nightly-version
+          git commit -m "Update nightly"
+          git push -u origin $(date +"nightly-%Y-%m")
+
+      - name: Pull Request
+        uses: actions/github-script@v6
+        with:
+          script: |
+            const { repo, owner } = context.repo;
+
+            const result = await github.rest.pulls.create({
+              title: (new Date()).toLocaleString(
+                false,
+                { month: "long", year: "numeric" }
+              ) + " - Rust Nightly Update",
+              owner,
+              repo,
+              head: "nightly-" + (new Date()).toISOString().split("-").splice(0, 2).join("-"),
+              base: "develop",
+              body: "PR auto-generated by a GitHub workflow."
+            });
+
+            github.rest.issues.addLabels({
+              owner,
+              repo,
+              issue_number: result.data.number,
+              labels: ["improvement"]
+            });

.github/workflows/no-std.yml

@@ -0,0 +1,21 @@
+name: no-std build
+
+on:
+  push:
+    branches:
+      - develop
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Install Build Dependencies
+        uses: ./.github/actions/build-dependencies
+        with:
+          github-token: ${{ inputs.github-token }}
+
+      - name: Verify no-std builds
+        run: cd tests/no-std && cargo build --target riscv32imac-unknown-none-elf

.github/workflows/tests.yml

@@ -0,0 +1,85 @@
+name: Tests
+
+on:
+  push:
+    branches:
+      - develop
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  clippy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Get nightly version to use
+        id: nightly
+        run: echo "version=$(cat .github/nightly-version)" >> $GITHUB_OUTPUT
+
+      - name: Build Dependencies
+        uses: ./.github/actions/build-dependencies
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          rust-toolchain: ${{ steps.nightly.outputs.version }}
+          rust-components: clippy
+
+      - name: Run Clippy
+        # Allow dbg_macro when run locally, yet not when pushed
+        run: cargo clippy --all-features --all-targets -- -D clippy::dbg_macro $(grep "\S" ../../clippy-config | grep -v "#")
+
+  deny:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Advisory Cache
+        uses: actions/cache@v3
+        with:
+          path: ~/.cargo/advisory-db
+          key: rust-advisory-db
+
+      - name: Install cargo
+        uses: dtolnay/rust-toolchain@stable
+
+      - name: Install cargo deny
+        run: cargo install --locked cargo-deny
+
+      - name: Run cargo deny
+        run: cargo deny -L error --all-features check
+
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Test Dependencies
+        uses: ./.github/actions/test-dependencies
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build node
+        run: |
+          cd substrate/node
+          cargo build
+
+      - name: Run Tests
+        run: GITHUB_CI=true cargo test --all-features
+
+  fmt:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Get nightly version to use
+        id: nightly
+        run: echo "version=$(cat .github/nightly-version)" >> $GITHUB_OUTPUT
+
+      - name: Install rustfmt
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ steps.nightly.outputs.version }}
+          components: rustfmt
+
+      - name: Run rustfmt
+        run: cargo +${{ steps.nightly.outputs.version }} fmt -- --check

.gitignore

@@ -1,2 +1,2 @@
 target
-Cargo.lock
+.vscode

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "coins/monero/c/monero"]
-	path = coins/monero/c/monero
-	url = https://github.com/monero-project/monero

.rustfmt.toml

@@ -0,0 +1,16 @@
+tab_spaces = 2
+
+max_width = 100
+# Let the developer decide based on the 100 char line limit
+use_small_heuristics = "Max"
+
+error_on_line_overflow = true
+error_on_unformatted = true
+
+imports_granularity = "Crate"
+reorder_imports = false
+reorder_modules = false
+
+unstable_features = true
+spaces_around_ranges = true
+binop_separator = "Back"

AGPL-3.0

@@ -0,0 +1,661 @@
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU Affero General Public License is a free, copyleft license for
+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  Developers that use our General Public Licenses protect your rights
+with two steps: (1) assert copyright on the software, and (2) offer
+you this License which gives you legal permission to copy, distribute
+and/or modify the software.
+
+  A secondary benefit of defending all users' freedom is that
+improvements made in alternate versions of the program, if they
+receive widespread use, become available for other developers to
+incorporate.  Many developers of free software are heartened and
+encouraged by the resulting cooperation.  However, in the case of
+software used on network servers, this result may fail to come about.
+The GNU General Public License permits making a modified version and
+letting the public access it on a server without ever releasing its
+source code to the public.
+
+  The GNU Affero General Public License is designed specifically to
+ensure that, in such cases, the modified source code becomes available
+to the community.  It requires the operator of a network server to
+provide the source code of the modified version running there to the
+users of that server.  Therefore, public use of a modified version, on
+a publicly accessible server, gives the public access to the source
+code of the modified version.
+
+  An older license, called the Affero General Public License and
+published by Affero, was designed to accomplish similar goals.  This is
+a different license, not a version of the Affero GPL, but Affero has
+released a new version of the Affero GPL which permits relicensing under
+this license.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU Affero General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
+License.  Each licensee is addressed as "you".  "Licensees" and
+"recipients" may be individuals or organizations.
+
+  To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy.  The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+  A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+  To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy.  Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+  To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies.  Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+  An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License.  If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+  1. Source Code.
+
+  The "source code" for a work means the preferred form of the work
+for making modifications to it.  "Object code" means any non-source
+form of a work.
+
+  A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+  The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form.  A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+  The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities.  However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work.  For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+  The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+  The Corresponding Source for a work in source code form is that
+same work.
+
+  2. Basic Permissions.
+
+  All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met.  This License explicitly affirms your unlimited
+permission to run the unmodified Program.  The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work.  This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+  You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force.  You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright.  Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+  Conveying under any other circumstances is permitted solely under
+the conditions stated below.  Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+  3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+  No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+  When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+  4. Conveying Verbatim Copies.
+
+  You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+  You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+  5. Conveying Modified Source Versions.
+
+  You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+    a) The work must carry prominent notices stating that you modified
+    it, and giving a relevant date.
+
+    b) The work must carry prominent notices stating that it is
+    released under this License and any conditions added under section
+    7.  This requirement modifies the requirement in section 4 to
+    "keep intact all notices".
+
+    c) You must license the entire work, as a whole, under this
+    License to anyone who comes into possession of a copy.  This
+    License will therefore apply, along with any applicable section 7
+    additional terms, to the whole of the work, and all its parts,
+    regardless of how they are packaged.  This License gives no
+    permission to license the work in any other way, but it does not
+    invalidate such permission if you have separately received it.
+
+    d) If the work has interactive user interfaces, each must display
+    Appropriate Legal Notices; however, if the Program has interactive
+    interfaces that do not display Appropriate Legal Notices, your
+    work need not make them do so.
+
+  A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit.  Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+  6. Conveying Non-Source Forms.
+
+  You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+    a) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by the
+    Corresponding Source fixed on a durable physical medium
+    customarily used for software interchange.
+
+    b) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by a
+    written offer, valid for at least three years and valid for as
+    long as you offer spare parts or customer support for that product
+    model, to give anyone who possesses the object code either (1) a
+    copy of the Corresponding Source for all the software in the
+    product that is covered by this License, on a durable physical
+    medium customarily used for software interchange, for a price no
+    more than your reasonable cost of physically performing this
+    conveying of source, or (2) access to copy the
+    Corresponding Source from a network server at no charge.
+
+    c) Convey individual copies of the object code with a copy of the
+    written offer to provide the Corresponding Source.  This
+    alternative is allowed only occasionally and noncommercially, and
+    only if you received the object code with such an offer, in accord
+    with subsection 6b.
+
+    d) Convey the object code by offering access from a designated
+    place (gratis or for a charge), and offer equivalent access to the
+    Corresponding Source in the same way through the same place at no
+    further charge.  You need not require recipients to copy the
+    Corresponding Source along with the object code.  If the place to
+    copy the object code is a network server, the Corresponding Source
+    may be on a different server (operated by you or a third party)
+    that supports equivalent copying facilities, provided you maintain
+    clear directions next to the object code saying where to find the
+    Corresponding Source.  Regardless of what server hosts the
+    Corresponding Source, you remain obligated to ensure that it is
+    available for as long as needed to satisfy these requirements.
+
+    e) Convey the object code using peer-to-peer transmission, provided
+    you inform other peers where the object code and Corresponding
+    Source of the work are being offered to the general public at no
+    charge under subsection 6d.
+
+  A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+  A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling.  In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage.  For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product.  A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+  "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source.  The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+  If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information.  But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+  The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed.  Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+  Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+  7. Additional Terms.
+
+  "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law.  If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+  When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it.  (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.)  You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+  Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+    a) Disclaiming warranty or limiting liability differently from the
+    terms of sections 15 and 16 of this License; or
+
+    b) Requiring preservation of specified reasonable legal notices or
+    author attributions in that material or in the Appropriate Legal
+    Notices displayed by works containing it; or
+
+    c) Prohibiting misrepresentation of the origin of that material, or
+    requiring that modified versions of such material be marked in
+    reasonable ways as different from the original version; or
+
+    d) Limiting the use for publicity purposes of names of licensors or
+    authors of the material; or
+
+    e) Declining to grant rights under trademark law for use of some
+    trade names, trademarks, or service marks; or
+
+    f) Requiring indemnification of licensors and authors of that
+    material by anyone who conveys the material (or modified versions of
+    it) with contractual assumptions of liability to the recipient, for
+    any liability that these contractual assumptions directly impose on
+    those licensors and authors.
+
+  All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+  If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+  Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+  8. Termination.
+
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+  9. Acceptance Not Required for Having Copies.
+
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+  10. Automatic Licensing of Downstream Recipients.
+
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.
+
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+  11. Patents.
+
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".
+
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Remote Network Interaction; Use with the GNU General Public License.
+
+  Notwithstanding any other provision of this License, if you modify the
+Program, your modified version must prominently offer all users
+interacting with it remotely through a computer network (if your version
+supports such interaction) an opportunity to receive the Corresponding
+Source of your version by providing access to the Corresponding Source
+from a network server at no charge, through some standard or customary
+means of facilitating copying of software.  This Corresponding Source
+shall include the Corresponding Source for any work covered by version 3
+of the GNU General Public License that is incorporated pursuant to the
+following paragraph.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the work with which it is combined will remain governed by version
+3 of the GNU General Public License.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU Affero General Public License from time to time.  Such new versions
+will be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU Affero General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU Affero General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU Affero General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<https://www.gnu.org/licenses/>.

CONTRIBUTING.md

@@ -0,0 +1,37 @@
+# Contributing
+
+Contributions come in a variety of forms. Developing Serai, helping document it,
+using its libraries in another project, using and testing it, and simply sharing
+it are all valuable ways of contributing.
+
+This document will specifically focus on contributions to this repository in the
+form of code and documentation.
+
+### Rules
+
+- Stable native Rust, nightly wasm and tools.
+- `cargo fmt` must be used.
+- `cargo clippy` must pass, except for the ignored rules (`type_complexity` and
+`dead_code`).
+- The CI must pass.
+
+- Only use uppercase variable names when relevant to cryptography.
+
+- Use a two-space ident when possible.
+- Put a space after comment markers.
+- Don't use multiple newlines between sections of code.
+- Have a newline before EOF.
+
+### Guidelines
+
+- Sort inputs as core, std, third party, and then Serai.
+- Comment code reasonably.
+- Include tests for new features.
+- Sign commits.
+
+### Submission
+
+All submissions should be through GitHub. Contributions to a crate will be
+licensed according to the crate's existing license, with the crate's copyright
+holders (distinct from authors) having the right to re-license the crate via a
+unanimous decision.

Cargo.toml

@@ -1,15 +1,72 @@
 [workspace]
-
 members = [
+  "common/std-shims",
+  "common/zalloc",
+  "common/db",
+
   "crypto/transcript",
 
+  "crypto/ff-group-tests",
   "crypto/dalek-ff-group",
+  "crypto/ed448",
+  "crypto/ciphersuite",
+
   "crypto/multiexp",
 
+  "crypto/schnorr",
   "crypto/dleq",
+  "crypto/dkg",
   "crypto/frost",
+  "crypto/schnorrkel",
 
+  "coins/ethereum",
+  "coins/monero/generators",
   "coins/monero",
 
+  "message-queue",
+
+  "processor/messages",
   "processor",
+
+  "coordinator/tributary/tendermint",
+  "coordinator/tributary",
+  "coordinator",
+
+  "substrate/primitives",
+
+  "substrate/tokens/primitives",
+  "substrate/tokens/pallet",
+
+  "substrate/in-instructions/primitives",
+  "substrate/in-instructions/pallet",
+
+  "substrate/validator-sets/primitives",
+  "substrate/validator-sets/pallet",
+
+  "substrate/runtime",
+  "substrate/node",
+
+  "substrate/client",
+
+  "tests/no-std",
 ]
+
+# Always compile Monero (and a variety of dependencies) with optimizations due
+# to the extensive operations required for Bulletproofs
+[profile.dev.package]
+subtle = { opt-level = 3 }
+curve25519-dalek = { opt-level = 3 }
+
+ff = { opt-level = 3 }
+group = { opt-level = 3 }
+
+crypto-bigint = { opt-level = 3 }
+dalek-ff-group = { opt-level = 3 }
+minimal-ed448 = { opt-level = 3 }
+
+multiexp = { opt-level = 3 }
+
+monero-serai = { opt-level = 3 }
+
+[profile.release]
+panic = "unwind"

LICENSE

@@ -0,0 +1,8 @@
+Serai crates are licensed under one of two licenses, either MIT or AGPL-3.0,
+depending on the crate in question. Each crate declares their license in their
+`Cargo.toml` and includes a `LICENSE` file detailing its status. Additionally,
+a full copy of the AGPL-3.0 License is included in the root of this repository
+as a reference text. This copy should be provided with any distribution of a
+crate licensed under the AGPL-3.0, as per its terms.
+
+The GitHub actions (`.github/actions`) are licensed under the MIT license.

README.md

@@ -1,22 +1,44 @@
 # Serai
 
 Serai is a new DEX, built from the ground up, initially planning on listing
-Bitcoin, Ethereum, Monero, DAI, and USDC, offering a liquidity pool trading
-experience. Funds are stored in an economically secured threshold multisig
+Bitcoin, Ethereum, DAI, and Monero, offering a liquidity-pool-based trading
+experience. Funds are stored in an economically secured threshold-multisig
 wallet.
 
+[Getting Started](docs/Getting%20Started.md)
+
 ### Layout
 
-- `docs` - Documentation on the Serai protocol.
+- `audits`: Audits for various parts of Serai.
 
-- `coins` - Various coin libraries intended for usage in Serai yet also by the
-  wider community. This means they will always support the functionality Serai
-  needs, yet won't disadvantage other use cases when possible.
+- `docs`: Documentation on the Serai protocol.
 
-- `crypto` - A series of composable cryptographic libraries built around the
+- `common`: Crates containing utilities common to a variety of areas under
+  Serai, none neatly fitting under another category.
+
+- `crypto`: A series of composable cryptographic libraries built around the
   `ff`/`group` APIs achieving a variety of tasks. These range from generic
   infrastructure, to our IETF-compliant FROST implementation, to a DLEq proof as
   needed for Bitcoin-Monero atomic swaps.
 
-- `processor` - A generic chain processor to process data for Serai and process
+- `coins`: Various coin libraries intended for usage in Serai yet also by the
+  wider community. This means they will always support the functionality Serai
+  needs, yet won't disadvantage other use cases when possible.
+
+- `processor`: A generic chain processor to process data for Serai and process
   events from Serai, executing transactions as expected and needed.
+
+- `coordinator`: A service to manage processors and communicate over a P2P
+  network with other validators.
+
+- `substrate`: Substrate crates used to instantiate the Serai network.
+
+- `deploy`: Scripts to deploy a Serai node/test environment.
+
+### Links
+
+- [Twitter](https://twitter.com/SeraiDEX):         https://twitter.com/SeraiDEX
+- [Mastodon](https://cryptodon.lol/@serai):        https://cryptodon.lol/@serai
+- [Discord](https://discord.gg/mpEUtJR3vz):        https://discord.gg/mpEUtJR3vz
+- [Matrix](https://matrix.to/#/#serai:matrix.org):
+https://matrix.to/#/#serai:matrix.org

audits/Cypher Stack crypto March 2023/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Cypher Stack
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

audits/Cypher Stack crypto March 2023/README.md

@@ -0,0 +1,7 @@
+# Cypher Stack /crypto Audit, March 2023
+
+This audit was over the /crypto folder, excluding the ed448 crate, the `Ed448`
+ciphersuite in the ciphersuite crate, and the `dleq/experimental` feature. It is
+encompassing up to commit 669d2dbffc1dafb82a09d9419ea182667115df06.
+
+Please see https://github.com/cypherstack/serai-audit for provenance.

clippy-config

@@ -0,0 +1,51 @@
+# No warnings allowed
+-D warnings
+
+# nursery
+-D clippy::nursery
+# Erratic and unhelpful
+-A clippy::missing_const_for_fn
+# Too many false/irrelevant positives
+-A clippy::redundant_pub_crate
+# Flags on any debug_assert using an RNG
+-A clippy::debug_assert_with_mut_call
+# Stylistic preference
+-A clippy::option_if_let_else
+
+# pedantic
+-D clippy::unnecessary_wraps
+-D clippy::unused_async
+-D clippy::unused_self
+
+# restrictions
+
+# Safety
+-D clippy::as_conversions
+-D clippy::disallowed_script_idents
+-D clippy::wildcard_enum_match_arm
+
+# Clarity
+-D clippy::assertions_on_result_states
+-D clippy::deref_by_slicing
+-D clippy::empty_structs_with_brackets
+-D clippy::get_unwrap
+-D clippy::rest_pat_in_fully_bound_structs
+-D clippy::semicolon_inside_block
+-D clippy::tests_outside_test_module
+
+# Quality
+-D clippy::format_push_string
+-D clippy::string_to_string
+
+# These potentially should be enabled in the future
+# -D clippy::missing_errors_doc
+# -D clippy::missing_panics_doc
+# -D clippy::doc_markdown
+
+# TODO: Enable this
+# -D clippy::cargo
+
+# Not in nightly yet
+# -D clippy::redundant_type_annotations
+# -D clippy::big_endian_bytes
+# -D clippy::host_endian_bytes

coins/bitcoin/Cargo.toml

@@ -0,0 +1,37 @@
+[package]
+name = "bitcoin-serai"
+version = "0.2.0"
+description = "A Bitcoin library for FROST-signing transactions"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/coins/bitcoin"
+authors = ["Luke Parker <lukeparker5132@gmail.com>", "Vrx <vrx00@proton.me>"]
+edition = "2021"
+
+[dependencies]
+lazy_static = "1"
+thiserror = "1"
+
+zeroize = "^1.5"
+rand_core = "0.6"
+
+sha2 = "0.10"
+
+secp256k1 = { version = "0.27", features = ["global-context"] }
+bitcoin = { version = "0.30", features = ["serde"] }
+
+k256 = { version = "^0.13.1", default-features = false, features = ["std", "arithmetic", "bits"] }
+transcript = { package = "flexible-transcript", path = "../../crypto/transcript", version = "0.3", features = ["recommended"] }
+frost = { package = "modular-frost", path = "../../crypto/frost", version = "0.7", features = ["secp256k1"] }
+
+hex = "0.4"
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
+reqwest = { version = "0.11", features = ["json"] }
+
+[dev-dependencies]
+frost = { package = "modular-frost", path = "../../crypto/frost", version = "0.7", features = ["tests"] }
+
+tokio = { version = "1", features = ["full"] }
+
+[features]
+hazmat = []

coins/bitcoin/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022-2023 Luke Parker
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

coins/bitcoin/README.md

@@ -0,0 +1,4 @@
+# bitcoin-serai
+
+An application of [modular-frost](https://docs.rs/modular-frost) to Bitcoin
+transactions, enabling extremely-efficient multisigs.

coins/bitcoin/src/crypto.rs

@@ -0,0 +1,160 @@
+use core::fmt::Debug;
+use std::io;
+
+use lazy_static::lazy_static;
+
+use zeroize::Zeroizing;
+use rand_core::{RngCore, CryptoRng};
+
+use sha2::{Digest, Sha256};
+use transcript::Transcript;
+
+use secp256k1::schnorr::Signature;
+use k256::{
+  elliptic_curve::{
+    ops::Reduce,
+    sec1::{Tag, ToEncodedPoint},
+  },
+  U256, Scalar, ProjectivePoint,
+};
+use frost::{
+  curve::{Ciphersuite, Secp256k1},
+  Participant, ThresholdKeys, ThresholdView, FrostError,
+  algorithm::{Hram as HramTrait, Algorithm, Schnorr as FrostSchnorr},
+};
+
+use bitcoin::key::XOnlyPublicKey;
+
+/// Get the x coordinate of a non-infinity, even point. Panics on invalid input.
+pub fn x(key: &ProjectivePoint) -> [u8; 32] {
+  let encoded = key.to_encoded_point(true);
+  assert_eq!(encoded.tag(), Tag::CompressedEvenY, "x coordinate of odd key");
+  (*encoded.x().expect("point at infinity")).into()
+}
+
+/// Convert a non-infinite even point to a XOnlyPublicKey. Panics on invalid input.
+pub fn x_only(key: &ProjectivePoint) -> XOnlyPublicKey {
+  XOnlyPublicKey::from_slice(&x(key)).unwrap()
+}
+
+/// Make a point even by adding the generator until it is even. Returns the even point and the
+/// amount of additions required.
+pub fn make_even(mut key: ProjectivePoint) -> (ProjectivePoint, u64) {
+  let mut c = 0;
+  while key.to_encoded_point(true).tag() == Tag::CompressedOddY {
+    key += ProjectivePoint::GENERATOR;
+    c += 1;
+  }
+  (key, c)
+}
+
+/// A BIP-340 compatible HRAm for use with the modular-frost Schnorr Algorithm.
+///
+/// If passed an odd nonce, it will have the generator added until it is even.
+#[derive(Clone, Copy, Debug)]
+pub struct Hram {}
+
+lazy_static! {
+  static ref TAG_HASH: [u8; 32] = Sha256::digest(b"BIP0340/challenge").into();
+}
+
+#[allow(non_snake_case)]
+impl HramTrait<Secp256k1> for Hram {
+  fn hram(R: &ProjectivePoint, A: &ProjectivePoint, m: &[u8]) -> Scalar {
+    // Convert the nonce to be even
+    let (R, _) = make_even(*R);
+
+    let mut data = Sha256::new();
+    data.update(*TAG_HASH);
+    data.update(*TAG_HASH);
+    data.update(x(&R));
+    data.update(x(A));
+    data.update(m);
+
+    Scalar::reduce(U256::from_be_slice(&data.finalize()))
+  }
+}
+
+/// BIP-340 Schnorr signature algorithm.
+///
+/// This must be used with a ThresholdKeys whose group key is even. If it is odd, this will panic.
+#[derive(Clone)]
+pub struct Schnorr<T: Sync + Clone + Debug + Transcript>(FrostSchnorr<Secp256k1, T, Hram>);
+impl<T: Sync + Clone + Debug + Transcript> Schnorr<T> {
+  /// Construct a Schnorr algorithm continuing the specified transcript.
+  pub fn new(transcript: T) -> Schnorr<T> {
+    Schnorr(FrostSchnorr::new(transcript))
+  }
+}
+
+impl<T: Sync + Clone + Debug + Transcript> Algorithm<Secp256k1> for Schnorr<T> {
+  type Transcript = T;
+  type Addendum = ();
+  type Signature = Signature;
+
+  fn transcript(&mut self) -> &mut Self::Transcript {
+    self.0.transcript()
+  }
+
+  fn nonces(&self) -> Vec<Vec<ProjectivePoint>> {
+    self.0.nonces()
+  }
+
+  fn preprocess_addendum<R: RngCore + CryptoRng>(
+    &mut self,
+    rng: &mut R,
+    keys: &ThresholdKeys<Secp256k1>,
+  ) {
+    self.0.preprocess_addendum(rng, keys)
+  }
+
+  fn read_addendum<R: io::Read>(&self, reader: &mut R) -> io::Result<Self::Addendum> {
+    self.0.read_addendum(reader)
+  }
+
+  fn process_addendum(
+    &mut self,
+    view: &ThresholdView<Secp256k1>,
+    i: Participant,
+    addendum: (),
+  ) -> Result<(), FrostError> {
+    self.0.process_addendum(view, i, addendum)
+  }
+
+  fn sign_share(
+    &mut self,
+    params: &ThresholdView<Secp256k1>,
+    nonce_sums: &[Vec<<Secp256k1 as Ciphersuite>::G>],
+    nonces: Vec<Zeroizing<<Secp256k1 as Ciphersuite>::F>>,
+    msg: &[u8],
+  ) -> <Secp256k1 as Ciphersuite>::F {
+    self.0.sign_share(params, nonce_sums, nonces, msg)
+  }
+
+  #[must_use]
+  fn verify(
+    &self,
+    group_key: ProjectivePoint,
+    nonces: &[Vec<ProjectivePoint>],
+    sum: Scalar,
+  ) -> Option<Self::Signature> {
+    self.0.verify(group_key, nonces, sum).map(|mut sig| {
+      // Make the R of the final signature even
+      let offset;
+      (sig.R, offset) = make_even(sig.R);
+      // s = r + cx. Since we added to the r, add to s
+      sig.s += Scalar::from(offset);
+      // Convert to a secp256k1 signature
+      Signature::from_slice(&sig.serialize()[1 ..]).unwrap()
+    })
+  }
+
+  fn verify_share(
+    &self,
+    verification_share: ProjectivePoint,
+    nonces: &[Vec<ProjectivePoint>],
+    share: Scalar,
+  ) -> Result<Vec<(Scalar, ProjectivePoint)>, ()> {
+    self.0.verify_share(verification_share, nonces, share)
+  }
+}

coins/bitcoin/src/lib.rs

@@ -0,0 +1,19 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+
+/// The bitcoin Rust library.
+pub use bitcoin;
+
+/// Cryptographic helpers.
+#[cfg(feature = "hazmat")]
+pub mod crypto;
+#[cfg(not(feature = "hazmat"))]
+pub(crate) mod crypto;
+
+/// Wallet functionality to create transactions.
+pub mod wallet;
+/// A minimal asynchronous Bitcoin RPC client.
+pub mod rpc;
+
+#[cfg(test)]
+mod tests;

coins/bitcoin/src/rpc.rs

@@ -0,0 +1,145 @@
+use core::fmt::Debug;
+
+use thiserror::Error;
+
+use serde::{Deserialize, de::DeserializeOwned};
+use serde_json::json;
+
+use bitcoin::{
+  hashes::{Hash, hex::FromHex},
+  consensus::encode,
+  Txid, Transaction, BlockHash, Block,
+};
+
+#[derive(Clone, PartialEq, Eq, Debug, Deserialize)]
+pub struct Error {
+  code: isize,
+  message: String,
+}
+
+#[derive(Clone, Debug, Deserialize)]
+#[serde(untagged)]
+enum RpcResponse<T> {
+  Ok { result: T },
+  Err { error: Error },
+}
+
+/// A minimal asynchronous Bitcoin RPC client.
+#[derive(Clone, Debug)]
+pub struct Rpc(String);
+
+#[derive(Clone, PartialEq, Eq, Debug, Error)]
+pub enum RpcError {
+  #[error("couldn't connect to node")]
+  ConnectionError,
+  #[error("request had an error: {0:?}")]
+  RequestError(Error),
+  #[error("node sent an invalid response")]
+  InvalidResponse,
+}
+
+impl Rpc {
+  pub async fn new(url: String) -> Result<Rpc, RpcError> {
+    let rpc = Rpc(url);
+    // Make an RPC request to verify the node is reachable and sane
+    rpc.get_latest_block_number().await?;
+    Ok(rpc)
+  }
+
+  /// Perform an arbitrary RPC call.
+  pub async fn rpc_call<Response: DeserializeOwned + Debug>(
+    &self,
+    method: &str,
+    params: serde_json::Value,
+  ) -> Result<Response, RpcError> {
+    let client = reqwest::Client::new();
+    let res = client
+      .post(&self.0)
+      .json(&json!({ "jsonrpc": "2.0", "method": method, "params": params }))
+      .send()
+      .await
+      .map_err(|_| RpcError::ConnectionError)?
+      .text()
+      .await
+      .map_err(|_| RpcError::ConnectionError)?;
+
+    let res: RpcResponse<Response> =
+      serde_json::from_str(&res).map_err(|_| RpcError::InvalidResponse)?;
+    match res {
+      RpcResponse::Ok { result } => Ok(result),
+      RpcResponse::Err { error } => Err(RpcError::RequestError(error)),
+    }
+  }
+
+  /// Get the latest block's number.
+  ///
+  /// The genesis block's 'number' is zero. They increment from there.
+  pub async fn get_latest_block_number(&self) -> Result<usize, RpcError> {
+    // getblockcount doesn't return the amount of blocks on the current chain, yet the "height"
+    // of the current chain. The "height" of the current chain is defined as the "height" of the
+    // tip block of the current chain. The "height" of a block is defined as the amount of blocks
+    // present when the block was created. Accordingly, the genesis block has height 0, and
+    // getblockcount will return 0 when it's only the only block, despite their being one block.
+    self.rpc_call("getblockcount", json!([])).await
+  }
+
+  /// Get the hash of a block by the block's number.
+  pub async fn get_block_hash(&self, number: usize) -> Result<[u8; 32], RpcError> {
+    let mut hash = *self
+      .rpc_call::<BlockHash>("getblockhash", json!([number]))
+      .await?
+      .as_raw_hash()
+      .as_byte_array();
+    // bitcoin stores the inner bytes in reverse order.
+    hash.reverse();
+    Ok(hash)
+  }
+
+  /// Get a block's number by its hash.
+  pub async fn get_block_number(&self, hash: &[u8; 32]) -> Result<usize, RpcError> {
+    #[derive(Deserialize, Debug)]
+    struct Number {
+      height: usize,
+    }
+    Ok(self.rpc_call::<Number>("getblockheader", json!([hex::encode(hash)])).await?.height)
+  }
+
+  /// Get a block by its hash.
+  pub async fn get_block(&self, hash: &[u8; 32]) -> Result<Block, RpcError> {
+    let hex = self.rpc_call::<String>("getblock", json!([hex::encode(hash), 0])).await?;
+    let bytes: Vec<u8> = FromHex::from_hex(&hex).map_err(|_| RpcError::InvalidResponse)?;
+    let block: Block = encode::deserialize(&bytes).map_err(|_| RpcError::InvalidResponse)?;
+
+    let mut block_hash = *block.block_hash().as_raw_hash().as_byte_array();
+    block_hash.reverse();
+    if hash != &block_hash {
+      Err(RpcError::InvalidResponse)?;
+    }
+
+    Ok(block)
+  }
+
+  /// Publish a transaction.
+  pub async fn send_raw_transaction(&self, tx: &Transaction) -> Result<Txid, RpcError> {
+    let txid = self.rpc_call("sendrawtransaction", json!([encode::serialize_hex(tx)])).await?;
+    if txid != tx.txid() {
+      Err(RpcError::InvalidResponse)?;
+    }
+    Ok(txid)
+  }
+
+  /// Get a transaction by its hash.
+  pub async fn get_transaction(&self, hash: &[u8; 32]) -> Result<Transaction, RpcError> {
+    let hex = self.rpc_call::<String>("getrawtransaction", json!([hex::encode(hash)])).await?;
+    let bytes: Vec<u8> = FromHex::from_hex(&hex).map_err(|_| RpcError::InvalidResponse)?;
+    let tx: Transaction = encode::deserialize(&bytes).map_err(|_| RpcError::InvalidResponse)?;
+
+    let mut tx_hash = *tx.txid().as_raw_hash().as_byte_array();
+    tx_hash.reverse();
+    if hash != &tx_hash {
+      Err(RpcError::InvalidResponse)?;
+    }
+
+    Ok(tx)
+  }
+}

coins/bitcoin/src/tests/crypto.rs

@@ -0,0 +1,47 @@
+use rand_core::OsRng;
+
+use sha2::{Digest, Sha256};
+
+use secp256k1::{SECP256K1, Message};
+
+use k256::Scalar;
+use transcript::{Transcript, RecommendedTranscript};
+use frost::{
+  curve::Secp256k1,
+  Participant,
+  tests::{algorithm_machines, key_gen, sign},
+};
+
+use crate::{
+  bitcoin::hashes::{Hash as HashTrait, sha256::Hash},
+  crypto::{x_only, make_even, Schnorr},
+};
+
+#[test]
+fn test_algorithm() {
+  let mut keys = key_gen::<_, Secp256k1>(&mut OsRng);
+  const MESSAGE: &[u8] = b"Hello, World!";
+
+  for (_, keys) in keys.iter_mut() {
+    let (_, offset) = make_even(keys.group_key());
+    *keys = keys.offset(Scalar::from(offset));
+  }
+
+  let algo =
+    Schnorr::<RecommendedTranscript>::new(RecommendedTranscript::new(b"bitcoin-serai sign test"));
+  let sig = sign(
+    &mut OsRng,
+    algo.clone(),
+    keys.clone(),
+    algorithm_machines(&mut OsRng, algo, &keys),
+    &Sha256::digest(MESSAGE),
+  );
+
+  SECP256K1
+    .verify_schnorr(
+      &sig,
+      &Message::from(Hash::hash(MESSAGE)),
+      &x_only(&keys[&Participant::new(1).unwrap()].group_key()),
+    )
+    .unwrap()
+}

coins/bitcoin/src/tests/mod.rs

@@ -0,0 +1 @@
+mod crypto;

coins/bitcoin/src/wallet/mod.rs

@@ -0,0 +1,160 @@
+use std::{
+  io::{self, Read, Write},
+  collections::HashMap,
+};
+
+use k256::{
+  elliptic_curve::sec1::{Tag, ToEncodedPoint},
+  Scalar, ProjectivePoint,
+};
+use frost::{
+  curve::{Ciphersuite, Secp256k1},
+  ThresholdKeys,
+};
+
+use bitcoin::{
+  consensus::encode::{Decodable, serialize},
+  key::TweakedPublicKey,
+  OutPoint, ScriptBuf, TxOut, Transaction, Block, Network, Address,
+};
+
+use crate::crypto::{x_only, make_even};
+
+mod send;
+pub use send::*;
+
+/// Tweak keys to ensure they're usable with Bitcoin.
+pub fn tweak_keys(keys: &ThresholdKeys<Secp256k1>) -> ThresholdKeys<Secp256k1> {
+  let (_, offset) = make_even(keys.group_key());
+  keys.offset(Scalar::from(offset))
+}
+
+/// Return the Taproot address for a public key.
+pub fn address(network: Network, key: ProjectivePoint) -> Option<Address> {
+  if key.to_encoded_point(true).tag() != Tag::CompressedEvenY {
+    return None;
+  }
+
+  Some(Address::p2tr_tweaked(TweakedPublicKey::dangerous_assume_tweaked(x_only(&key)), network))
+}
+
+/// A spendable output.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct ReceivedOutput {
+  // The scalar offset to obtain the key usable to spend this output.
+  offset: Scalar,
+  // The output to spend.
+  output: TxOut,
+  // The TX ID and vout of the output to spend.
+  outpoint: OutPoint,
+}
+
+impl ReceivedOutput {
+  /// The offset for this output.
+  pub fn offset(&self) -> Scalar {
+    self.offset
+  }
+
+  /// The outpoint for this output.
+  pub fn outpoint(&self) -> &OutPoint {
+    &self.outpoint
+  }
+
+  /// The value of this output.
+  pub fn value(&self) -> u64 {
+    self.output.value
+  }
+
+  /// Read a ReceivedOutput from a generic satisfying Read.
+  pub fn read<R: Read>(r: &mut R) -> io::Result<ReceivedOutput> {
+    Ok(ReceivedOutput {
+      offset: Secp256k1::read_F(r)?,
+      output: TxOut::consensus_decode(r)
+        .map_err(|_| io::Error::new(io::ErrorKind::Other, "invalid TxOut"))?,
+      outpoint: OutPoint::consensus_decode(r)
+        .map_err(|_| io::Error::new(io::ErrorKind::Other, "invalid OutPoint"))?,
+    })
+  }
+
+  /// Write a ReceivedOutput to a generic satisfying Write.
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    w.write_all(&self.offset.to_bytes())?;
+    w.write_all(&serialize(&self.output))?;
+    w.write_all(&serialize(&self.outpoint))
+  }
+
+  /// Serialize a ReceivedOutput to a Vec<u8>.
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut res = vec![];
+    self.write(&mut res).unwrap();
+    res
+  }
+}
+
+/// A transaction scanner capable of being used with HDKD schemes.
+#[derive(Clone, Debug)]
+pub struct Scanner {
+  key: ProjectivePoint,
+  scripts: HashMap<ScriptBuf, Scalar>,
+}
+
+impl Scanner {
+  /// Construct a Scanner for a key.
+  ///
+  /// Returns None if this key can't be scanned for.
+  pub fn new(key: ProjectivePoint) -> Option<Scanner> {
+    let mut scripts = HashMap::new();
+    // Uses Network::Bitcoin since network is irrelevant here
+    scripts.insert(address(Network::Bitcoin, key)?.script_pubkey(), Scalar::ZERO);
+    Some(Scanner { key, scripts })
+  }
+
+  /// Register an offset to scan for.
+  ///
+  /// Due to Bitcoin's requirement that points are even, not every offset may be used.
+  /// If an offset isn't usable, it will be incremented until it is. If this offset is already
+  /// present, None is returned. Else, Some(offset) will be, with the used offset.
+  pub fn register_offset(&mut self, mut offset: Scalar) -> Option<Scalar> {
+    loop {
+      match address(Network::Bitcoin, self.key + (ProjectivePoint::GENERATOR * offset)) {
+        Some(address) => {
+          let script = address.script_pubkey();
+          if self.scripts.contains_key(&script) {
+            None?;
+          }
+          self.scripts.insert(script, offset);
+          return Some(offset);
+        }
+        None => offset += Scalar::ONE,
+      }
+    }
+  }
+
+  /// Scan a transaction.
+  pub fn scan_transaction(&self, tx: &Transaction) -> Vec<ReceivedOutput> {
+    let mut res = vec![];
+    for (vout, output) in tx.output.iter().enumerate() {
+      if let Some(offset) = self.scripts.get(&output.script_pubkey) {
+        res.push(ReceivedOutput {
+          offset: *offset,
+          output: output.clone(),
+          outpoint: OutPoint::new(tx.txid(), u32::try_from(vout).unwrap()),
+        });
+      }
+    }
+    res
+  }
+
+  /// Scan a block.
+  ///
+  /// This will also scan the coinbase transaction which is bound by maturity. If received outputs
+  /// must be immediately spendable, a post-processing pass is needed to remove those outputs.
+  /// Alternatively, scan_transaction can be called on `block.txdata[1 ..]`.
+  pub fn scan_block(&self, block: &Block) -> Vec<ReceivedOutput> {
+    let mut res = vec![];
+    for tx in &block.txdata {
+      res.extend(self.scan_transaction(tx));
+    }
+    res
+  }
+}

coins/bitcoin/src/wallet/send.rs

@@ -0,0 +1,382 @@
+use std::{
+  io::{self, Read},
+  collections::HashMap,
+};
+
+use thiserror::Error;
+
+use rand_core::{RngCore, CryptoRng};
+
+use transcript::{Transcript, RecommendedTranscript};
+
+use k256::{elliptic_curve::sec1::ToEncodedPoint, Scalar};
+use frost::{curve::Secp256k1, Participant, ThresholdKeys, FrostError, sign::*};
+
+use bitcoin::{
+  sighash::{TapSighashType, SighashCache, Prevouts},
+  absolute::LockTime,
+  script::{PushBytesBuf, ScriptBuf},
+  OutPoint, Sequence, Witness, TxIn, TxOut, Transaction, Network, Address,
+};
+
+use crate::{
+  crypto::Schnorr,
+  wallet::{address, ReceivedOutput},
+};
+
+#[rustfmt::skip]
+// https://github.com/bitcoin/bitcoin/blob/306ccd4927a2efe325c8d84be1bdb79edeb29b04/src/policy/policy.h#L27
+const MAX_STANDARD_TX_WEIGHT: u64 = 400_000;
+
+#[rustfmt::skip]
+//https://github.com/bitcoin/bitcoin/blob/a245429d680eb95cf4c0c78e58e63e3f0f5d979a/src/test/transaction_tests.cpp#L815-L816
+const DUST: u64 = 674;
+
+#[derive(Clone, PartialEq, Eq, Debug, Error)]
+pub enum TransactionError {
+  #[error("no inputs were specified")]
+  NoInputs,
+  #[error("no outputs were created")]
+  NoOutputs,
+  #[error("a specified payment's amount was less than bitcoin's required minimum")]
+  DustPayment,
+  #[error("too much data was specified")]
+  TooMuchData,
+  #[error("not enough funds for these payments")]
+  NotEnoughFunds,
+  #[error("transaction was too large")]
+  TooLargeTransaction,
+}
+
+/// A signable transaction, clone-able across attempts.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct SignableTransaction {
+  tx: Transaction,
+  offsets: Vec<Scalar>,
+  prevouts: Vec<TxOut>,
+  needed_fee: u64,
+}
+
+impl SignableTransaction {
+  fn calculate_weight(inputs: usize, payments: &[(Address, u64)], change: Option<&Address>) -> u64 {
+    // Expand this a full transaction in order to use the bitcoin library's weight function
+    let mut tx = Transaction {
+      version: 2,
+      lock_time: LockTime::ZERO,
+      input: vec![
+        TxIn {
+          // This is a fixed size
+          // See https://developer.bitcoin.org/reference/transactions.html#raw-transaction-format
+          previous_output: OutPoint::default(),
+          // This is empty for a Taproot spend
+          script_sig: ScriptBuf::new(),
+          // This is fixed size, yet we do use Sequence::MAX
+          sequence: Sequence::MAX,
+          // Our witnesses contains a single 64-byte signature
+          witness: Witness::from_slice(&[vec![0; 64]])
+        };
+        inputs
+      ],
+      output: payments
+        .iter()
+        // The payment is a fixed size so we don't have to use it here
+        // The script pub key is not of a fixed size and does have to be used here
+        .map(|payment| TxOut { value: payment.1, script_pubkey: payment.0.script_pubkey() })
+        .collect(),
+    };
+    if let Some(change) = change {
+      // Use a 0 value since we're currently unsure what the change amount will be, and since
+      // the value is fixed size (so any value could be used here)
+      tx.output.push(TxOut { value: 0, script_pubkey: change.script_pubkey() });
+    }
+    u64::try_from(tx.weight()).unwrap()
+  }
+
+  /// Returns the fee necessary for this transaction to achieve the fee rate specified at
+  /// construction.
+  ///
+  /// The actual fee this transaction will use is `sum(inputs) - sum(outputs)`.
+  pub fn needed_fee(&self) -> u64 {
+    self.needed_fee
+  }
+
+  /// Create a new SignableTransaction.
+  ///
+  /// If a change address is specified, any leftover funds will be sent to it if the leftover funds
+  /// exceed the minimum output amount. If a change address isn't specified, all leftover funds
+  /// will become part of the paid fee.
+  ///
+  /// If data is specified, an OP_RETURN output will be added with it.
+  pub fn new(
+    mut inputs: Vec<ReceivedOutput>,
+    payments: &[(Address, u64)],
+    change: Option<Address>,
+    data: Option<Vec<u8>>,
+    fee_per_weight: u64,
+  ) -> Result<SignableTransaction, TransactionError> {
+    if inputs.is_empty() {
+      Err(TransactionError::NoInputs)?;
+    }
+
+    if payments.is_empty() && change.is_none() && data.is_none() {
+      Err(TransactionError::NoOutputs)?;
+    }
+
+    for (_, amount) in payments {
+      if *amount < DUST {
+        Err(TransactionError::DustPayment)?;
+      }
+    }
+
+    if data.as_ref().map(|data| data.len()).unwrap_or(0) > 80 {
+      Err(TransactionError::TooMuchData)?;
+    }
+
+    let input_sat = inputs.iter().map(|input| input.output.value).sum::<u64>();
+    let offsets = inputs.iter().map(|input| input.offset).collect();
+    let tx_ins = inputs
+      .iter()
+      .map(|input| TxIn {
+        previous_output: input.outpoint,
+        script_sig: ScriptBuf::new(),
+        sequence: Sequence::MAX,
+        witness: Witness::new(),
+      })
+      .collect::<Vec<_>>();
+
+    let payment_sat = payments.iter().map(|payment| payment.1).sum::<u64>();
+    let mut tx_outs = payments
+      .iter()
+      .map(|payment| TxOut { value: payment.1, script_pubkey: payment.0.script_pubkey() })
+      .collect::<Vec<_>>();
+
+    // Add the OP_RETURN output
+    if let Some(data) = data {
+      tx_outs.push(TxOut {
+        value: 0,
+        script_pubkey: ScriptBuf::new_op_return(
+          &PushBytesBuf::try_from(data)
+            .expect("data didn't fit into PushBytes depsite being checked"),
+        ),
+      })
+    }
+
+    let mut weight = Self::calculate_weight(tx_ins.len(), payments, None);
+    let mut needed_fee = fee_per_weight * weight;
+    if input_sat < (payment_sat + needed_fee) {
+      Err(TransactionError::NotEnoughFunds)?;
+    }
+
+    // If there's a change address, check if there's change to give it
+    if let Some(change) = change.as_ref() {
+      let weight_with_change = Self::calculate_weight(tx_ins.len(), payments, Some(change));
+      let fee_with_change = fee_per_weight * weight_with_change;
+      if let Some(value) = input_sat.checked_sub(payment_sat + fee_with_change) {
+        if value >= DUST {
+          tx_outs.push(TxOut { value, script_pubkey: change.script_pubkey() });
+          weight = weight_with_change;
+          needed_fee = fee_with_change;
+        }
+      }
+    }
+
+    if tx_outs.is_empty() {
+      Err(TransactionError::NoOutputs)?;
+    }
+
+    if weight > MAX_STANDARD_TX_WEIGHT {
+      Err(TransactionError::TooLargeTransaction)?;
+    }
+
+    Ok(SignableTransaction {
+      tx: Transaction { version: 2, lock_time: LockTime::ZERO, input: tx_ins, output: tx_outs },
+      offsets,
+      prevouts: inputs.drain(..).map(|input| input.output).collect(),
+      needed_fee,
+    })
+  }
+
+  /// Create a multisig machine for this transaction.
+  ///
+  /// Returns None if the wrong keys are used.
+  pub fn multisig(
+    self,
+    keys: ThresholdKeys<Secp256k1>,
+    mut transcript: RecommendedTranscript,
+  ) -> Option<TransactionMachine> {
+    transcript.domain_separate(b"bitcoin_transaction");
+    transcript.append_message(b"root_key", keys.group_key().to_encoded_point(true).as_bytes());
+
+    // Transcript the inputs and outputs
+    let tx = &self.tx;
+    for input in &tx.input {
+      transcript.append_message(b"input_hash", input.previous_output.txid);
+      transcript.append_message(b"input_output_index", input.previous_output.vout.to_le_bytes());
+    }
+    for payment in &tx.output {
+      transcript.append_message(b"output_script", payment.script_pubkey.as_bytes());
+      transcript.append_message(b"output_amount", payment.value.to_le_bytes());
+    }
+
+    let mut sigs = vec![];
+    for i in 0 .. tx.input.len() {
+      let mut transcript = transcript.clone();
+      transcript.append_message(b"signing_input", u32::try_from(i).unwrap().to_le_bytes());
+
+      let offset = keys.clone().offset(self.offsets[i]);
+      if address(Network::Bitcoin, offset.group_key())?.script_pubkey() !=
+        self.prevouts[i].script_pubkey
+      {
+        None?;
+      }
+
+      sigs.push(AlgorithmMachine::new(
+        Schnorr::new(transcript),
+        keys.clone().offset(self.offsets[i]),
+      ));
+    }
+
+    Some(TransactionMachine { tx: self, sigs })
+  }
+}
+
+/// A FROST signing machine to produce a Bitcoin transaction.
+///
+/// This does not support caching its preprocess. When sign is called, the message must be empty.
+/// This will panic if it isn't.
+pub struct TransactionMachine {
+  tx: SignableTransaction,
+  sigs: Vec<AlgorithmMachine<Secp256k1, Schnorr<RecommendedTranscript>>>,
+}
+
+impl PreprocessMachine for TransactionMachine {
+  type Preprocess = Vec<Preprocess<Secp256k1, ()>>;
+  type Signature = Transaction;
+  type SignMachine = TransactionSignMachine;
+
+  fn preprocess<R: RngCore + CryptoRng>(
+    mut self,
+    rng: &mut R,
+  ) -> (Self::SignMachine, Self::Preprocess) {
+    let mut preprocesses = Vec::with_capacity(self.sigs.len());
+    let sigs = self
+      .sigs
+      .drain(..)
+      .map(|sig| {
+        let (sig, preprocess) = sig.preprocess(rng);
+        preprocesses.push(preprocess);
+        sig
+      })
+      .collect();
+
+    (TransactionSignMachine { tx: self.tx, sigs }, preprocesses)
+  }
+}
+
+pub struct TransactionSignMachine {
+  tx: SignableTransaction,
+  sigs: Vec<AlgorithmSignMachine<Secp256k1, Schnorr<RecommendedTranscript>>>,
+}
+
+impl SignMachine<Transaction> for TransactionSignMachine {
+  type Params = ();
+  type Keys = ThresholdKeys<Secp256k1>;
+  type Preprocess = Vec<Preprocess<Secp256k1, ()>>;
+  type SignatureShare = Vec<SignatureShare<Secp256k1>>;
+  type SignatureMachine = TransactionSignatureMachine;
+
+  fn cache(self) -> CachedPreprocess {
+    unimplemented!(
+      "Bitcoin transactions don't support caching their preprocesses due to {}",
+      "being already bound to a specific transaction"
+    );
+  }
+
+  fn from_cache(
+    _: (),
+    _: ThresholdKeys<Secp256k1>,
+    _: CachedPreprocess,
+  ) -> Result<Self, FrostError> {
+    unimplemented!(
+      "Bitcoin transactions don't support caching their preprocesses due to {}",
+      "being already bound to a specific transaction"
+    );
+  }
+
+  fn read_preprocess<R: Read>(&self, reader: &mut R) -> io::Result<Self::Preprocess> {
+    self.sigs.iter().map(|sig| sig.read_preprocess(reader)).collect()
+  }
+
+  fn sign(
+    mut self,
+    commitments: HashMap<Participant, Self::Preprocess>,
+    msg: &[u8],
+  ) -> Result<(TransactionSignatureMachine, Self::SignatureShare), FrostError> {
+    if !msg.is_empty() {
+      panic!("message was passed to the TransactionMachine when it generates its own");
+    }
+
+    let commitments = (0 .. self.sigs.len())
+      .map(|c| {
+        commitments
+          .iter()
+          .map(|(l, commitments)| (*l, commitments[c].clone()))
+          .collect::<HashMap<_, _>>()
+      })
+      .collect::<Vec<_>>();
+
+    let mut cache = SighashCache::new(&self.tx.tx);
+    // Sign committing to all inputs
+    let prevouts = Prevouts::All(&self.tx.prevouts);
+
+    let mut shares = Vec::with_capacity(self.sigs.len());
+    let sigs = self
+      .sigs
+      .drain(..)
+      .enumerate()
+      .map(|(i, sig)| {
+        let (sig, share) = sig.sign(
+          commitments[i].clone(),
+          cache
+            .taproot_key_spend_signature_hash(i, &prevouts, TapSighashType::Default)
+            .unwrap()
+            .as_ref(),
+        )?;
+        shares.push(share);
+        Ok(sig)
+      })
+      .collect::<Result<_, _>>()?;
+
+    Ok((TransactionSignatureMachine { tx: self.tx.tx, sigs }, shares))
+  }
+}
+
+pub struct TransactionSignatureMachine {
+  tx: Transaction,
+  sigs: Vec<AlgorithmSignatureMachine<Secp256k1, Schnorr<RecommendedTranscript>>>,
+}
+
+impl SignatureMachine<Transaction> for TransactionSignatureMachine {
+  type SignatureShare = Vec<SignatureShare<Secp256k1>>;
+
+  fn read_share<R: Read>(&self, reader: &mut R) -> io::Result<Self::SignatureShare> {
+    self.sigs.iter().map(|sig| sig.read_share(reader)).collect()
+  }
+
+  fn complete(
+    mut self,
+    mut shares: HashMap<Participant, Self::SignatureShare>,
+  ) -> Result<Transaction, FrostError> {
+    for (input, schnorr) in self.tx.input.iter_mut().zip(self.sigs.drain(..)) {
+      let sig = schnorr.complete(
+        shares.iter_mut().map(|(l, shares)| (*l, shares.remove(0))).collect::<HashMap<_, _>>(),
+      )?;
+
+      let mut witness = Witness::new();
+      witness.push(sig.as_ref());
+      input.witness = witness;
+    }
+
+    Ok(self.tx)
+  }
+}

coins/bitcoin/tests/rpc.rs

@@ -0,0 +1,25 @@
+use bitcoin_serai::{bitcoin::hashes::Hash as HashTrait, rpc::RpcError};
+
+mod runner;
+use runner::rpc;
+
+async_sequential! {
+  async fn test_rpc() {
+    let rpc = rpc().await;
+
+    // Test get_latest_block_number and get_block_hash by round tripping them
+    let latest = rpc.get_latest_block_number().await.unwrap();
+    let hash = rpc.get_block_hash(latest).await.unwrap();
+    assert_eq!(rpc.get_block_number(&hash).await.unwrap(), latest);
+
+    // Test this actually is the latest block number by checking asking for the next block's errors
+    assert!(matches!(rpc.get_block_hash(latest + 1).await, Err(RpcError::RequestError(_))));
+
+    // Test get_block by checking the received block's hash matches the request
+    let block = rpc.get_block(&hash).await.unwrap();
+    // Hashes are stored in reverse. It's bs from Satoshi
+    let mut block_hash = *block.block_hash().as_raw_hash().as_byte_array();
+    block_hash.reverse();
+    assert_eq!(hash, block_hash);
+  }
+}

coins/bitcoin/tests/runner.rs

@@ -0,0 +1,44 @@
+use bitcoin_serai::rpc::Rpc;
+
+use tokio::sync::Mutex;
+
+lazy_static::lazy_static! {
+  pub static ref SEQUENTIAL: Mutex<()> = Mutex::new(());
+}
+
+#[allow(dead_code)]
+pub(crate) async fn rpc() -> Rpc {
+  let rpc = Rpc::new("http://serai:seraidex@127.0.0.1:18443".to_string()).await.unwrap();
+
+  // If this node has already been interacted with, clear its chain
+  if rpc.get_latest_block_number().await.unwrap() > 0 {
+    rpc
+      .rpc_call(
+        "invalidateblock",
+        serde_json::json!([hex::encode(rpc.get_block_hash(1).await.unwrap())]),
+      )
+      .await
+      .unwrap()
+  }
+
+  rpc
+}
+
+#[macro_export]
+macro_rules! async_sequential {
+  ($(async fn $name: ident() $body: block)*) => {
+    $(
+      #[tokio::test]
+      async fn $name() {
+        let guard = runner::SEQUENTIAL.lock().await;
+        let local = tokio::task::LocalSet::new();
+        local.run_until(async move {
+          if let Err(err) = tokio::task::spawn_local(async move { $body }).await {
+            drop(guard);
+            Err(err).unwrap()
+          }
+        }).await;
+      }
+    )*
+  }
+}

coins/bitcoin/tests/wallet.rs

@@ -0,0 +1,348 @@
+use std::collections::HashMap;
+
+use rand_core::{RngCore, OsRng};
+
+use transcript::{Transcript, RecommendedTranscript};
+
+use k256::{
+  elliptic_curve::{
+    group::{ff::Field, Group},
+    sec1::{Tag, ToEncodedPoint},
+  },
+  Scalar, ProjectivePoint,
+};
+use frost::{
+  curve::Secp256k1,
+  Participant, ThresholdKeys,
+  tests::{THRESHOLD, key_gen, sign_without_caching},
+};
+
+use bitcoin_serai::{
+  bitcoin::{
+    hashes::Hash as HashTrait,
+    blockdata::opcodes::all::OP_RETURN,
+    script::{PushBytesBuf, Instruction, Instructions, Script},
+    OutPoint, TxOut, Transaction, Network, Address,
+  },
+  wallet::{tweak_keys, address, ReceivedOutput, Scanner, TransactionError, SignableTransaction},
+  rpc::Rpc,
+};
+
+mod runner;
+use runner::rpc;
+
+const FEE: u64 = 20;
+
+fn is_even(key: ProjectivePoint) -> bool {
+  key.to_encoded_point(true).tag() == Tag::CompressedEvenY
+}
+
+async fn send_and_get_output(rpc: &Rpc, scanner: &Scanner, key: ProjectivePoint) -> ReceivedOutput {
+  let block_number = rpc.get_latest_block_number().await.unwrap() + 1;
+
+  rpc
+    .rpc_call::<Vec<String>>(
+      "generatetoaddress",
+      serde_json::json!([1, address(Network::Regtest, key).unwrap()]),
+    )
+    .await
+    .unwrap();
+
+  // Mine until maturity
+  rpc
+    .rpc_call::<Vec<String>>(
+      "generatetoaddress",
+      serde_json::json!([100, Address::p2sh(Script::empty(), Network::Regtest).unwrap()]),
+    )
+    .await
+    .unwrap();
+
+  let block = rpc.get_block(&rpc.get_block_hash(block_number).await.unwrap()).await.unwrap();
+
+  let mut outputs = scanner.scan_block(&block);
+  assert_eq!(outputs, scanner.scan_transaction(&block.txdata[0]));
+
+  assert_eq!(outputs.len(), 1);
+  assert_eq!(outputs[0].outpoint(), &OutPoint::new(block.txdata[0].txid(), 0));
+  assert_eq!(outputs[0].value(), block.txdata[0].output[0].value);
+
+  assert_eq!(
+    ReceivedOutput::read::<&[u8]>(&mut outputs[0].serialize().as_ref()).unwrap(),
+    outputs[0]
+  );
+
+  outputs.swap_remove(0)
+}
+
+fn keys() -> (HashMap<Participant, ThresholdKeys<Secp256k1>>, ProjectivePoint) {
+  let mut keys = key_gen(&mut OsRng);
+  for (_, keys) in keys.iter_mut() {
+    *keys = tweak_keys(keys);
+  }
+  let key = keys.values().next().unwrap().group_key();
+  (keys, key)
+}
+
+fn sign(
+  keys: &HashMap<Participant, ThresholdKeys<Secp256k1>>,
+  tx: SignableTransaction,
+) -> Transaction {
+  let mut machines = HashMap::new();
+  for i in (1 ..= THRESHOLD).map(|i| Participant::new(i).unwrap()) {
+    machines.insert(
+      i,
+      tx.clone()
+        .multisig(keys[&i].clone(), RecommendedTranscript::new(b"bitcoin-serai Test Transaction"))
+        .unwrap(),
+    );
+  }
+  sign_without_caching(&mut OsRng, machines, &[])
+}
+
+#[test]
+fn test_tweak_keys() {
+  let mut even = false;
+  let mut odd = false;
+
+  // Generate keys until we get an even set and an odd set
+  while !(even && odd) {
+    let mut keys = key_gen(&mut OsRng).drain().next().unwrap().1;
+    if is_even(keys.group_key()) {
+      // Tweaking should do nothing
+      assert_eq!(tweak_keys(&keys).group_key(), keys.group_key());
+
+      even = true;
+    } else {
+      let tweaked = tweak_keys(&keys).group_key();
+      assert_ne!(tweaked, keys.group_key());
+      // Tweaking should produce an even key
+      assert!(is_even(tweaked));
+
+      // Verify it uses the smallest possible offset
+      while keys.group_key().to_encoded_point(true).tag() == Tag::CompressedOddY {
+        keys = keys.offset(Scalar::ONE);
+      }
+      assert_eq!(tweaked, keys.group_key());
+
+      odd = true;
+    }
+  }
+}
+
+async_sequential! {
+  async fn test_scanner() {
+    // Test Scanners are creatable for even keys.
+    for _ in 0 .. 128 {
+      let key = ProjectivePoint::random(&mut OsRng);
+      assert_eq!(Scanner::new(key).is_some(), is_even(key));
+    }
+
+    let mut key = ProjectivePoint::random(&mut OsRng);
+    while !is_even(key) {
+      key += ProjectivePoint::GENERATOR;
+    }
+
+    {
+      let mut scanner = Scanner::new(key).unwrap();
+      for _ in 0 .. 128 {
+        let mut offset = Scalar::random(&mut OsRng);
+        let registered = scanner.register_offset(offset).unwrap();
+        // Registering this again should return None
+        assert!(scanner.register_offset(offset).is_none());
+
+        // We can only register offsets resulting in even keys
+        // Make this even
+        while !is_even(key + (ProjectivePoint::GENERATOR * offset)) {
+          offset += Scalar::ONE;
+        }
+        // Ensure it matches the registered offset
+        assert_eq!(registered, offset);
+        // Assert registering this again fails
+        assert!(scanner.register_offset(offset).is_none());
+      }
+    }
+
+    let rpc = rpc().await;
+    let mut scanner = Scanner::new(key).unwrap();
+
+    assert_eq!(send_and_get_output(&rpc, &scanner, key).await.offset(), Scalar::ZERO);
+
+    // Register an offset and test receiving to it
+    let offset = scanner.register_offset(Scalar::random(&mut OsRng)).unwrap();
+    assert_eq!(
+      send_and_get_output(&rpc, &scanner, key + (ProjectivePoint::GENERATOR * offset))
+        .await
+        .offset(),
+      offset
+    );
+  }
+
+  async fn test_transaction_errors() {
+    let (_, key) = keys();
+
+    let rpc = rpc().await;
+    let scanner = Scanner::new(key).unwrap();
+
+    let output = send_and_get_output(&rpc, &scanner, key).await;
+    assert_eq!(output.offset(), Scalar::ZERO);
+
+    let inputs = vec![output];
+    let addr = || address(Network::Regtest, key).unwrap();
+    let payments = vec![(addr(), 1000)];
+
+    assert!(SignableTransaction::new(inputs.clone(), &payments, None, None, FEE).is_ok());
+
+    assert_eq!(
+      SignableTransaction::new(vec![], &payments, None, None, FEE),
+      Err(TransactionError::NoInputs)
+    );
+
+    // No change
+    assert!(SignableTransaction::new(inputs.clone(), &[(addr(), 1000)], None, None, FEE).is_ok());
+    // Consolidation TX
+    assert!(SignableTransaction::new(inputs.clone(), &[], Some(addr()), None, FEE).is_ok());
+    // Data
+    assert!(SignableTransaction::new(inputs.clone(), &[], None, Some(vec![]), FEE).is_ok());
+    // No outputs
+    assert_eq!(
+      SignableTransaction::new(inputs.clone(), &[], None, None, FEE),
+      Err(TransactionError::NoOutputs),
+    );
+
+    assert_eq!(
+      SignableTransaction::new(inputs.clone(), &[(addr(), 1)], None, None, FEE),
+      Err(TransactionError::DustPayment),
+    );
+
+    assert!(
+      SignableTransaction::new(inputs.clone(), &payments, None, Some(vec![0; 80]), FEE).is_ok()
+    );
+    assert_eq!(
+      SignableTransaction::new(inputs.clone(), &payments, None, Some(vec![0; 81]), FEE),
+      Err(TransactionError::TooMuchData),
+    );
+
+    assert_eq!(
+      SignableTransaction::new(inputs.clone(), &[(addr(), inputs[0].value() * 2)], None, None, FEE),
+      Err(TransactionError::NotEnoughFunds),
+    );
+
+    assert_eq!(
+      SignableTransaction::new(inputs, &vec![(addr(), 1000); 10000], None, None, 0),
+      Err(TransactionError::TooLargeTransaction),
+    );
+  }
+
+  async fn test_send() {
+    let (keys, key) = keys();
+
+    let rpc = rpc().await;
+    let mut scanner = Scanner::new(key).unwrap();
+
+    // Get inputs, one not offset and one offset
+    let output = send_and_get_output(&rpc, &scanner, key).await;
+    assert_eq!(output.offset(), Scalar::ZERO);
+
+    let offset = scanner.register_offset(Scalar::random(&mut OsRng)).unwrap();
+    let offset_key = key + (ProjectivePoint::GENERATOR * offset);
+    let offset_output = send_and_get_output(&rpc, &scanner, offset_key).await;
+    assert_eq!(offset_output.offset(), offset);
+
+    // Declare payments, change, fee
+    let payments = [
+      (address(Network::Regtest, key).unwrap(), 1005),
+      (address(Network::Regtest, offset_key).unwrap(), 1007)
+    ];
+
+    let change_offset = scanner.register_offset(Scalar::random(&mut OsRng)).unwrap();
+    let change_key = key + (ProjectivePoint::GENERATOR * change_offset);
+    let change_addr = address(Network::Regtest, change_key).unwrap();
+
+    // Create and sign the TX
+    let tx = SignableTransaction::new(
+      vec![output.clone(), offset_output.clone()],
+      &payments,
+      Some(change_addr.clone()),
+      None,
+      FEE
+    ).unwrap();
+    let needed_fee = tx.needed_fee();
+    let tx = sign(&keys, tx);
+
+    assert_eq!(tx.output.len(), 3);
+
+    // Ensure we can scan it
+    let outputs = scanner.scan_transaction(&tx);
+    for (o, output) in outputs.iter().enumerate() {
+      assert_eq!(output.outpoint(), &OutPoint::new(tx.txid(), u32::try_from(o).unwrap()));
+      assert_eq!(&ReceivedOutput::read::<&[u8]>(&mut output.serialize().as_ref()).unwrap(), output);
+    }
+
+    assert_eq!(outputs[0].offset(), Scalar::ZERO);
+    assert_eq!(outputs[1].offset(), offset);
+    assert_eq!(outputs[2].offset(), change_offset);
+
+    // Make sure the payments were properly created
+    for ((output, scanned), payment) in tx.output.iter().zip(outputs.iter()).zip(payments.iter()) {
+      assert_eq!(output, &TxOut { script_pubkey: payment.0.script_pubkey(), value: payment.1 });
+      assert_eq!(scanned.value(), payment.1 );
+    }
+
+    // Make sure the change is correct
+    assert_eq!(needed_fee, u64::try_from(tx.weight()).unwrap() * FEE);
+    let input_value = output.value() + offset_output.value();
+    let output_value = tx.output.iter().map(|output| output.value).sum::<u64>();
+    assert_eq!(input_value - output_value, needed_fee);
+
+    let change_amount =
+      input_value - payments.iter().map(|payment| payment.1).sum::<u64>() - needed_fee;
+    assert_eq!(
+      tx.output[2],
+      TxOut { script_pubkey: change_addr.script_pubkey(), value: change_amount },
+    );
+
+    // This also tests send_raw_transaction and get_transaction, which the RPC test can't
+    // effectively test
+    rpc.send_raw_transaction(&tx).await.unwrap();
+    let mut hash = *tx.txid().as_raw_hash().as_byte_array();
+    hash.reverse();
+    assert_eq!(tx, rpc.get_transaction(&hash).await.unwrap());
+  }
+
+  async fn test_data() {
+    let (keys, key) = keys();
+
+    let rpc = rpc().await;
+    let scanner = Scanner::new(key).unwrap();
+
+    let output = send_and_get_output(&rpc, &scanner, key).await;
+    assert_eq!(output.offset(), Scalar::ZERO);
+
+    let data_len = 60 + usize::try_from(OsRng.next_u64() % 21).unwrap();
+    let mut data = vec![0; data_len];
+    OsRng.fill_bytes(&mut data);
+
+    let tx = sign(
+      &keys,
+      SignableTransaction::new(
+        vec![output],
+        &[],
+        address(Network::Regtest, key),
+        Some(data.clone()),
+        FEE
+      ).unwrap()
+    );
+
+    assert!(tx.output[0].script_pubkey.is_op_return());
+    let check = |mut instructions: Instructions| {
+      assert_eq!(instructions.next().unwrap().unwrap(), Instruction::Op(OP_RETURN));
+      assert_eq!(
+        instructions.next().unwrap().unwrap(),
+        Instruction::PushBytes(&PushBytesBuf::try_from(data.clone()).unwrap()),
+      );
+      assert!(instructions.next().is_none());
+    };
+    check(tx.output[0].script_pubkey.instructions());
+    check(tx.output[0].script_pubkey.instructions_minimal());
+  }
+}

coins/ethereum/.gitignore

@@ -0,0 +1,3 @@
+# solidity build outputs
+cache
+artifacts

coins/ethereum/Cargo.toml

@@ -0,0 +1,37 @@
+[package]
+name = "ethereum-serai"
+version = "0.1.0"
+description = "An Ethereum library supporting Schnorr signing and on-chain verification"
+license = "AGPL-3.0-only"
+repository = "https://github.com/serai-dex/serai/tree/develop/coins/ethereum"
+authors = ["Luke Parker <lukeparker5132@gmail.com>", "Elizabeth Binks <elizabethjbinks@gmail.com>"]
+edition = "2021"
+publish = false
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[dependencies]
+thiserror = "1"
+rand_core = "0.6"
+
+serde_json = "1"
+serde = "1"
+
+sha2 = "0.10"
+sha3 = "0.10"
+
+group = "0.13"
+k256 = { version = "^0.13.1", default-features = false, features = ["std", "arithmetic", "bits", "ecdsa"] }
+frost = { package = "modular-frost", path = "../../crypto/frost", features = ["secp256k1", "tests"] }
+
+eyre = "0.6"
+
+ethers = { version = "2", default-features = false, features = ["abigen", "ethers-solc"] }
+
+[build-dependencies]
+ethers-solc = "2"
+
+[dev-dependencies]
+tokio = { version = "1", features = ["macros"] }

coins/ethereum/LICENSE

@@ -0,0 +1,15 @@
+AGPL-3.0-only license
+
+Copyright (c) 2022-2023 Luke Parker
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License Version 3 as
+published by the Free Software Foundation.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.

coins/ethereum/README.md

@@ -0,0 +1,9 @@
+# Ethereum
+
+This package contains Ethereum-related functionality, specifically deploying and
+interacting with Serai contracts.
+
+### Dependencies
+
+- solc
+- [Foundry](https://github.com/foundry-rs/foundry)

coins/ethereum/build.rs

@@ -0,0 +1,16 @@
+use ethers_solc::{Project, ProjectPathsConfig};
+
+fn main() {
+  println!("cargo:rerun-if-changed=contracts");
+  println!("cargo:rerun-if-changed=artifacts");
+
+  // configure the project with all its paths, solc, cache etc.
+  let project = Project::builder()
+    .paths(ProjectPathsConfig::hardhat(env!("CARGO_MANIFEST_DIR")).unwrap())
+    .build()
+    .unwrap();
+  project.compile().unwrap();
+
+  // Tell Cargo that if a source file changes, to rerun this build script.
+  project.rerun_if_sources_changed();
+}

coins/ethereum/contracts/Schnorr.sol

@@ -0,0 +1,36 @@
+//SPDX-License-Identifier: AGPLv3
+pragma solidity ^0.8.0;
+
+// see https://github.com/noot/schnorr-verify for implementation details
+contract Schnorr {
+  // secp256k1 group order
+  uint256 constant public Q =
+    0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141;
+
+  // parity := public key y-coord parity (27 or 28)
+  // px := public key x-coord
+  // message := 32-byte message
+  // s := schnorr signature
+  // e := schnorr signature challenge
+  function verify(
+    uint8 parity,
+    bytes32 px,
+    bytes32 message,
+    bytes32 s,
+    bytes32 e
+  ) public view returns (bool) {
+    // ecrecover = (m, v, r, s);
+    bytes32 sp = bytes32(Q - mulmod(uint256(s), uint256(px), Q));
+    bytes32 ep = bytes32(Q - mulmod(uint256(e), uint256(px), Q));
+
+    require(sp != 0);
+    // the ecrecover precompile implementation checks that the `r` and `s`
+    // inputs are non-zero (in this case, `px` and `ep`), thus we don't need to
+    // check if they're zero.will make me 
+    address R = ecrecover(sp, parity, px, ep);
+    require(R != address(0), "ecrecover failed");
+    return e == keccak256(
+      abi.encodePacked(R, uint8(parity), px, block.chainid, message)
+    );
+  }
+}

coins/ethereum/src/contract.rs

@@ -0,0 +1,52 @@
+use crate::crypto::ProcessedSignature;
+use ethers::{contract::ContractFactory, prelude::*, solc::artifacts::contract::ContractBytecode};
+use eyre::{eyre, Result};
+use std::fs::File;
+use std::sync::Arc;
+use thiserror::Error;
+
+#[derive(Error, Debug)]
+pub enum EthereumError {
+  #[error("failed to verify Schnorr signature")]
+  VerificationError,
+}
+
+abigen!(
+  Schnorr,
+  "./artifacts/Schnorr.sol/Schnorr.json",
+  event_derives(serde::Deserialize, serde::Serialize),
+);
+
+pub async fn deploy_schnorr_verifier_contract(
+  client: Arc<SignerMiddleware<Provider<Http>, LocalWallet>>,
+) -> Result<Schnorr<SignerMiddleware<Provider<Http>, LocalWallet>>> {
+  let path = "./artifacts/Schnorr.sol/Schnorr.json";
+  let artifact: ContractBytecode = serde_json::from_reader(File::open(path).unwrap()).unwrap();
+  let abi = artifact.abi.unwrap();
+  let bin = artifact.bytecode.unwrap().object;
+  let factory = ContractFactory::new(abi, bin.into_bytes().unwrap(), client.clone());
+  let contract = factory.deploy(())?.send().await?;
+  let contract = Schnorr::new(contract.address(), client);
+  Ok(contract)
+}
+
+pub async fn call_verify(
+  contract: &Schnorr<SignerMiddleware<Provider<Http>, LocalWallet>>,
+  params: &ProcessedSignature,
+) -> Result<()> {
+  if contract
+    .verify(
+      params.parity + 27,
+      params.px.to_bytes().into(),
+      params.message,
+      params.s.to_bytes().into(),
+      params.e.to_bytes().into(),
+    )
+    .call()
+    .await?
+  {
+    Ok(())
+  } else {
+    Err(eyre!(EthereumError::VerificationError))
+  }
+}

coins/ethereum/src/crypto.rs

@@ -0,0 +1,107 @@
+use sha3::{Digest, Keccak256};
+
+use group::Group;
+use k256::{
+  elliptic_curve::{
+    bigint::ArrayEncoding, ops::Reduce, point::DecompressPoint, sec1::ToEncodedPoint,
+  },
+  AffinePoint, ProjectivePoint, Scalar, U256,
+};
+
+use frost::{algorithm::Hram, curve::Secp256k1};
+
+pub fn keccak256(data: &[u8]) -> [u8; 32] {
+  Keccak256::digest(data).try_into().unwrap()
+}
+
+pub fn hash_to_scalar(data: &[u8]) -> Scalar {
+  Scalar::reduce(U256::from_be_slice(&keccak256(data)))
+}
+
+pub fn address(point: &ProjectivePoint) -> [u8; 20] {
+  let encoded_point = point.to_encoded_point(false);
+  keccak256(&encoded_point.as_ref()[1 .. 65])[12 .. 32].try_into().unwrap()
+}
+
+pub fn ecrecover(message: Scalar, v: u8, r: Scalar, s: Scalar) -> Option<[u8; 20]> {
+  if r.is_zero().into() || s.is_zero().into() {
+    return None;
+  }
+
+  #[allow(non_snake_case)]
+  let R = AffinePoint::decompress(&r.to_bytes(), v.into());
+  #[allow(non_snake_case)]
+  if let Some(R) = Option::<AffinePoint>::from(R) {
+    #[allow(non_snake_case)]
+    let R = ProjectivePoint::from(R);
+
+    let r = r.invert().unwrap();
+    let u1 = ProjectivePoint::GENERATOR * (-message * r);
+    let u2 = R * (s * r);
+    let key: ProjectivePoint = u1 + u2;
+    if !bool::from(key.is_identity()) {
+      return Some(address(&key));
+    }
+  }
+
+  None
+}
+
+#[derive(Clone, Default)]
+pub struct EthereumHram {}
+impl Hram<Secp256k1> for EthereumHram {
+  #[allow(non_snake_case)]
+  fn hram(R: &ProjectivePoint, A: &ProjectivePoint, m: &[u8]) -> Scalar {
+    let a_encoded_point = A.to_encoded_point(true);
+    let mut a_encoded = a_encoded_point.as_ref().to_owned();
+    a_encoded[0] += 25; // Ethereum uses 27/28 for point parity
+    let mut data = address(R).to_vec();
+    data.append(&mut a_encoded);
+    data.append(&mut m.to_vec());
+    Scalar::reduce(U256::from_be_slice(&keccak256(&data)))
+  }
+}
+
+pub struct ProcessedSignature {
+  pub s: Scalar,
+  pub px: Scalar,
+  pub parity: u8,
+  pub message: [u8; 32],
+  pub e: Scalar,
+}
+
+#[allow(non_snake_case)]
+pub fn preprocess_signature_for_ecrecover(
+  m: [u8; 32],
+  R: &ProjectivePoint,
+  s: Scalar,
+  A: &ProjectivePoint,
+  chain_id: U256,
+) -> (Scalar, Scalar) {
+  let processed_sig = process_signature_for_contract(m, R, s, A, chain_id);
+  let sr = processed_sig.s.mul(&processed_sig.px).negate();
+  let er = processed_sig.e.mul(&processed_sig.px).negate();
+  (sr, er)
+}
+
+#[allow(non_snake_case)]
+pub fn process_signature_for_contract(
+  m: [u8; 32],
+  R: &ProjectivePoint,
+  s: Scalar,
+  A: &ProjectivePoint,
+  chain_id: U256,
+) -> ProcessedSignature {
+  let encoded_pk = A.to_encoded_point(true);
+  let px = &encoded_pk.as_ref()[1 .. 33];
+  let px_scalar = Scalar::reduce(U256::from_be_slice(px));
+  let e = EthereumHram::hram(R, A, &[chain_id.to_be_byte_array().as_slice(), &m].concat());
+  ProcessedSignature {
+    s,
+    px: px_scalar,
+    parity: &encoded_pk.as_ref()[0] - 2,
+    #[allow(non_snake_case)]
+    message: m,
+    e,
+  }
+}

coins/ethereum/src/lib.rs

@@ -0,0 +1,2 @@
+pub mod contract;
+pub mod crypto;

coins/ethereum/tests/contract.rs

@@ -0,0 +1,71 @@
+use std::{convert::TryFrom, sync::Arc, time::Duration};
+
+use rand_core::OsRng;
+
+use ::k256::{elliptic_curve::bigint::ArrayEncoding, U256};
+
+use ethers::{
+  prelude::*,
+  utils::{keccak256, Anvil, AnvilInstance},
+};
+
+use frost::{
+  curve::Secp256k1,
+  Participant,
+  algorithm::IetfSchnorr,
+  tests::{key_gen, algorithm_machines, sign},
+};
+
+use ethereum_serai::{
+  crypto,
+  contract::{Schnorr, call_verify, deploy_schnorr_verifier_contract},
+};
+
+async fn deploy_test_contract(
+) -> (u32, AnvilInstance, Schnorr<SignerMiddleware<Provider<Http>, LocalWallet>>) {
+  let anvil = Anvil::new().spawn();
+
+  let wallet: LocalWallet = anvil.keys()[0].clone().into();
+  let provider =
+    Provider::<Http>::try_from(anvil.endpoint()).unwrap().interval(Duration::from_millis(10u64));
+  let chain_id = provider.get_chainid().await.unwrap().as_u32();
+  let client = Arc::new(SignerMiddleware::new_with_provider_chain(provider, wallet).await.unwrap());
+
+  (chain_id, anvil, deploy_schnorr_verifier_contract(client).await.unwrap())
+}
+
+#[tokio::test]
+async fn test_deploy_contract() {
+  deploy_test_contract().await;
+}
+
+#[tokio::test]
+async fn test_ecrecover_hack() {
+  let (chain_id, _anvil, contract) = deploy_test_contract().await;
+  let chain_id = U256::from(chain_id);
+
+  let keys = key_gen::<_, Secp256k1>(&mut OsRng);
+  let group_key = keys[&Participant::new(1).unwrap()].group_key();
+
+  const MESSAGE: &[u8] = b"Hello, World!";
+  let hashed_message = keccak256(MESSAGE);
+
+  let full_message = &[chain_id.to_be_byte_array().as_slice(), &hashed_message].concat();
+
+  let algo = IetfSchnorr::<Secp256k1, crypto::EthereumHram>::ietf();
+  let sig = sign(
+    &mut OsRng,
+    algo.clone(),
+    keys.clone(),
+    algorithm_machines(&mut OsRng, algo, &keys),
+    full_message,
+  );
+  let mut processed_sig =
+    crypto::process_signature_for_contract(hashed_message, &sig.R, sig.s, &group_key, chain_id);
+
+  call_verify(&contract, &processed_sig).await.unwrap();
+
+  // test invalid signature fails
+  processed_sig.message[0] = 0;
+  assert!(call_verify(&contract, &processed_sig).await.is_err());
+}

coins/ethereum/tests/crypto.rs

@@ -0,0 +1,92 @@
+use k256::{
+  elliptic_curve::{bigint::ArrayEncoding, ops::Reduce, sec1::ToEncodedPoint},
+  ProjectivePoint, Scalar, U256,
+};
+use frost::{curve::Secp256k1, Participant};
+
+use ethereum_serai::crypto::*;
+
+#[test]
+fn test_ecrecover() {
+  use rand_core::OsRng;
+  use sha2::Sha256;
+  use sha3::{Digest, Keccak256};
+  use k256::ecdsa::{hazmat::SignPrimitive, signature::DigestVerifier, SigningKey, VerifyingKey};
+
+  let private = SigningKey::random(&mut OsRng);
+  let public = VerifyingKey::from(&private);
+
+  const MESSAGE: &[u8] = b"Hello, World!";
+  let (sig, recovery_id) = private
+    .as_nonzero_scalar()
+    .try_sign_prehashed_rfc6979::<Sha256>(&Keccak256::digest(MESSAGE), b"")
+    .unwrap();
+  #[allow(clippy::unit_cmp)] // Intended to assert this wasn't changed to Result<bool>
+  {
+    assert_eq!(public.verify_digest(Keccak256::new_with_prefix(MESSAGE), &sig).unwrap(), ());
+  }
+
+  assert_eq!(
+    ecrecover(hash_to_scalar(MESSAGE), recovery_id.unwrap().is_y_odd().into(), *sig.r(), *sig.s())
+      .unwrap(),
+    address(&ProjectivePoint::from(public.as_affine()))
+  );
+}
+
+#[test]
+fn test_signing() {
+  use frost::{
+    algorithm::IetfSchnorr,
+    tests::{algorithm_machines, key_gen, sign},
+  };
+  use rand_core::OsRng;
+
+  let keys = key_gen::<_, Secp256k1>(&mut OsRng);
+  let _group_key = keys[&Participant::new(1).unwrap()].group_key();
+
+  const MESSAGE: &[u8] = b"Hello, World!";
+
+  let algo = IetfSchnorr::<Secp256k1, EthereumHram>::ietf();
+  let _sig = sign(
+    &mut OsRng,
+    algo,
+    keys.clone(),
+    algorithm_machines(&mut OsRng, IetfSchnorr::<Secp256k1, EthereumHram>::ietf(), &keys),
+    MESSAGE,
+  );
+}
+
+#[test]
+fn test_ecrecover_hack() {
+  use frost::{
+    algorithm::IetfSchnorr,
+    tests::{algorithm_machines, key_gen, sign},
+  };
+  use rand_core::OsRng;
+
+  let keys = key_gen::<_, Secp256k1>(&mut OsRng);
+  let group_key = keys[&Participant::new(1).unwrap()].group_key();
+  let group_key_encoded = group_key.to_encoded_point(true);
+  let group_key_compressed = group_key_encoded.as_ref();
+  let group_key_x = Scalar::reduce(U256::from_be_slice(&group_key_compressed[1 .. 33]));
+
+  const MESSAGE: &[u8] = b"Hello, World!";
+  let hashed_message = keccak256(MESSAGE);
+  let chain_id = U256::ONE;
+
+  let full_message = &[chain_id.to_be_byte_array().as_slice(), &hashed_message].concat();
+
+  let algo = IetfSchnorr::<Secp256k1, EthereumHram>::ietf();
+  let sig = sign(
+    &mut OsRng,
+    algo.clone(),
+    keys.clone(),
+    algorithm_machines(&mut OsRng, algo, &keys),
+    full_message,
+  );
+
+  let (sr, er) =
+    preprocess_signature_for_ecrecover(hashed_message, &sig.R, sig.s, &group_key, chain_id);
+  let q = ecrecover(sr, group_key_compressed[0] - 2, group_key_x, er).unwrap();
+  assert_eq!(q, address(&sig.R));
+}

coins/ethereum/tests/mod.rs

@@ -0,0 +1,2 @@
+mod contract;
+mod crypto;

coins/monero/.gitignore

@@ -1 +0,0 @@
-c/.build

coins/monero/Cargo.toml

@@ -1,52 +1,107 @@
 [package]
 name = "monero-serai"
-version = "0.1.0"
-description = "A modern Monero wallet library"
+version = "0.1.4-alpha"
+description = "A modern Monero transaction library"
 license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/coins/monero"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 edition = "2021"
 
-[build-dependencies]
-cc = "1.0"
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
 
 [dependencies]
-hex-literal = "0.3"
-lazy_static = "1"
-thiserror = "1"
+std-shims = { path = "../../common/std-shims", version = "0.1", default-features = false }
 
-rand_core = "0.6"
-rand_chacha = { version = "0.3", optional = true }
-rand = "0.8"
-rand_distr = "0.4"
+async-trait = { version = "0.1", default-features = false }
+thiserror = { version = "1", optional = true }
 
-subtle = "2.4"
+zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive"] }
+subtle = { version = "^2.4", default-features = false }
 
-tiny-keccak = { version = "2", features = ["keccak"] }
-blake2 = { version = "0.10", optional = true }
+rand_core = { version = "0.6", default-features = false }
+# Used to send transactions
+rand = { version = "0.8", default-features = false }
+rand_chacha = { version = "0.3", default-features = false }
+# Used to select decoys
+rand_distr = { version = "0.4", default-features = false }
 
-curve25519-dalek = { version = "3", features = ["std"] }
+crc = { version = "3", default-features = false }
+sha3 = { version = "0.10", default-features = false }
 
-group = { version = "0.12" }
-dalek-ff-group = { path = "../../crypto/dalek-ff-group" }
+curve25519-dalek = { version = "^3.2", default-features = false }
 
-transcript = { package = "flexible-transcript", path = "../../crypto/transcript", features = ["recommended"], optional = true }
-frost = { package = "modular-frost", path = "../../crypto/frost", features = ["ed25519"], optional = true }
-dleq = { package = "dleq-serai", path = "../../crypto/dleq", features = ["serialize"], optional = true }
+# Used for the hash to curve, along with the more complicated proofs
+group = { version = "0.13", default-features = false }
+dalek-ff-group = { path = "../../crypto/dalek-ff-group", version = "0.3", default-features = false }
+multiexp = { path = "../../crypto/multiexp", version = "0.3", default-features = false, features = ["batch"] }
 
-hex = "0.4"
-serde = { version = "1.0", features = ["derive"] }
-serde_json = "1.0"
+# Needed for multisig
+transcript = { package = "flexible-transcript", path = "../../crypto/transcript", version = "0.3", default-features = false, features = ["recommended"], optional = true }
+dleq = { path = "../../crypto/dleq", version = "0.3", features = ["serialize"], optional = true }
+frost = { package = "modular-frost", path = "../../crypto/frost", version = "0.7", features = ["ed25519"], optional = true }
 
-base58-monero = "1"
-monero-epee-bin-serde = "1.0"
-monero = "0.16"
+monero-generators = { path = "generators", version = "0.3", default-features = false }
 
-reqwest = { version = "0.11", features = ["json"] }
+futures = { version = "0.3", default-features = false, features = ["alloc"], optional = true }
 
-[features]
-experimental = []
-multisig = ["rand_chacha", "blake2", "transcript", "frost", "dleq"]
+hex-literal = "0.4"
+hex = { version = "0.4", default-features = false, features = ["alloc"] }
+serde = { version = "1", default-features = false, features = ["derive"] }
+serde_json = { version = "1", default-features = false, features = ["alloc"] }
+
+base58-monero = { version = "1", git = "https://github.com/monero-rs/base58-monero", rev = "5045e8d2b817b3b6c1190661f504e879bc769c29", default-features = false, features = ["check"] }
+
+# Used for the provided RPC
+digest_auth = { version = "0.3", optional = true }
+reqwest = { version = "0.11", features = ["json"], optional = true }
+
+# Used for the binaries
+tokio = { version = "1", features = ["full"], optional = true }
+
+[build-dependencies]
+dalek-ff-group = { path = "../../crypto/dalek-ff-group", version = "0.3", default-features = false }
+monero-generators = { path = "generators", version = "0.3", default-features = false }
 
 [dev-dependencies]
-sha2 = "0.10"
 tokio = { version = "1", features = ["full"] }
+monero-rpc = "0.3"
+
+frost = { package = "modular-frost", path = "../../crypto/frost", version = "0.7", features = ["tests"] }
+
+[features]
+std = [
+  "std-shims/std",
+
+  "thiserror",
+
+  "zeroize/std",
+  "subtle/std",
+
+  "rand_core/std",
+  "rand_chacha/std",
+  "rand/std",
+  "rand_distr/std",
+
+  "sha3/std",
+
+  "curve25519-dalek/std",
+
+  "multiexp/std",
+
+  "monero-generators/std",
+
+  "futures/std",
+
+  "hex/std",
+  "serde/std",
+  "serde_json/std",
+]
+
+http_rpc = ["digest_auth", "reqwest"]
+multisig = ["transcript", "frost", "dleq", "std"]
+binaries = ["tokio"]
+experimental = []
+
+default = ["std", "http_rpc"]

coins/monero/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2022 Luke Parker
+Copyright (c) 2022-2023 Luke Parker
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

coins/monero/README.md

@@ -4,4 +4,46 @@ A modern Monero transaction library intended for usage in wallets. It prides
 itself on accuracy, correctness, and removing common pit falls developers may
 face.
 
-Threshold multisignature support is available via the `multisig` feature.
+monero-serai also offers the following features:
+
+- Featured Addresses
+- A FROST-based multisig orders of magnitude more performant than Monero's
+
+### Purpose and support
+
+monero-serai was written for Serai, a decentralized exchange aiming to support
+Monero. Despite this, monero-serai is intended to be a widely usable library,
+accurate to Monero. monero-serai guarantees the functionality needed for Serai,
+yet will not deprive functionality from other users.
+
+Various legacy transaction formats are not currently implemented, yet we are
+willing to add support for them. There aren't active development efforts around
+them however.
+
+### Caveats
+
+This library DOES attempt to do the following:
+
+- Create on-chain transactions identical to how wallet2 would (unless told not
+  to)
+- Not be detectable as monero-serai when scanning outputs
+- Not reveal spent outputs to the connected RPC node
+
+This library DOES NOT attempt to do the following:
+
+- Have identical RPC behavior when creating transactions
+- Be a wallet
+
+This means that monero-serai shouldn't be fingerprintable on-chain. It also
+shouldn't be fingerprintable if a targeted attack occurs to detect if the
+receiving wallet is monero-serai or wallet2. It also should be generally safe
+for usage with remote nodes.
+
+It won't hide from remote nodes it's monero-serai however, potentially
+allowing a remote node to profile you. The implications of this are left to the
+user to consider.
+
+It also won't act as a wallet, just as a transaction library. wallet2 has
+several *non-transaction-level* policies, such as always attempting to use two
+inputs to create transactions. These are considered out of scope to
+monero-serai.

coins/monero/build.rs

@@ -1,72 +1,67 @@
-use std::{env, path::Path, process::Command};
+use std::{
+  io::Write,
+  env,
+  path::Path,
+  fs::{File, remove_file},
+};
+
+use dalek_ff_group::EdwardsPoint;
+
+use monero_generators::bulletproofs_generators;
+
+fn serialize(generators_string: &mut String, points: &[EdwardsPoint]) {
+  for generator in points {
+    generators_string.extend(
+      format!(
+        "
+          dalek_ff_group::EdwardsPoint(
+            curve25519_dalek::edwards::CompressedEdwardsY({:?}).decompress().unwrap()
+          ),
+        ",
+        generator.compress().to_bytes()
+      )
+      .chars(),
+    );
+  }
+}
+
+fn generators(prefix: &'static str, path: &str) {
+  let generators = bulletproofs_generators(prefix.as_bytes());
+  #[allow(non_snake_case)]
+  let mut G_str = String::new();
+  serialize(&mut G_str, &generators.G);
+  #[allow(non_snake_case)]
+  let mut H_str = String::new();
+  serialize(&mut H_str, &generators.H);
+
+  let path = Path::new(&env::var("OUT_DIR").unwrap()).join(path);
+  let _ = remove_file(&path);
+  File::create(&path)
+    .unwrap()
+    .write_all(
+      format!(
+        "
+          pub static GENERATORS_CELL: OnceLock<Generators> = OnceLock::new();
+          pub fn GENERATORS() -> &'static Generators {{
+            GENERATORS_CELL.get_or_init(|| Generators {{
+              G: [
+                {G_str}
+              ],
+              H: [
+                {H_str}
+              ],
+            }})
+          }}
+        ",
+      )
+      .as_bytes(),
+    )
+    .unwrap();
+}
 
 fn main() {
-  if !Command::new("git").args(&["submodule", "update", "--init", "--recursive"]).status().unwrap().success() {
-    panic!("git failed to init submodules");
-  }
+  println!("cargo:rerun-if-changed=build.rs");
 
-  if !Command ::new("mkdir").args(&["-p", ".build"])
-    .current_dir(&Path::new("c")).status().unwrap().success() {
-      panic!("failed to create a directory to track build progress");
-  }
-
-  let out_dir = &env::var("OUT_DIR").unwrap();
-
-  // Use a file to signal if Monero was already built, as that should never be rebuilt
-  // If the signaling file was deleted, run this script again to rebuild Monero though
-  println!("cargo:rerun-if-changed=c/.build/monero");
-  if !Path::new("c/.build/monero").exists() {
-    if !Command::new("make").arg(format!("-j{}", &env::var("THREADS").unwrap_or("2".to_string())))
-      .current_dir(&Path::new("c/monero")).status().unwrap().success() {
-        panic!("make failed to build Monero. Please check your dependencies");
-    }
-
-    if !Command::new("touch").arg("monero")
-      .current_dir(&Path::new("c/.build")).status().unwrap().success() {
-        panic!("failed to create a file to label Monero as built");
-    }
-  }
-
-  println!("cargo:rerun-if-changed=c/wrapper.cpp");
-  cc::Build::new()
-    .static_flag(true)
-    .warnings(false)
-    .extra_warnings(false)
-    .flag("-Wno-deprecated-declarations")
-
-    .include("c/monero/external/supercop/include")
-    .include("c/monero/contrib/epee/include")
-    .include("c/monero/src")
-    .include("c/monero/build/release/generated_include")
-
-    .define("AUTO_INITIALIZE_EASYLOGGINGPP", None)
-    .include("c/monero/external/easylogging++")
-    .file("c/monero/external/easylogging++/easylogging++.cc")
-
-    .file("c/monero/src/common/aligned.c")
-    .file("c/monero/src/common/perf_timer.cpp")
-
-    .include("c/monero/src/crypto")
-    .file("c/monero/src/crypto/crypto-ops-data.c")
-    .file("c/monero/src/crypto/crypto-ops.c")
-    .file("c/monero/src/crypto/keccak.c")
-    .file("c/monero/src/crypto/hash.c")
-
-    .include("c/monero/src/device")
-    .file("c/monero/src/device/device_default.cpp")
-
-    .include("c/monero/src/ringct")
-    .file("c/monero/src/ringct/rctCryptoOps.c")
-    .file("c/monero/src/ringct/rctTypes.cpp")
-    .file("c/monero/src/ringct/rctOps.cpp")
-    .file("c/monero/src/ringct/multiexp.cc")
-    .file("c/monero/src/ringct/bulletproofs.cc")
-    .file("c/monero/src/ringct/rctSigs.cpp")
-
-    .file("c/wrapper.cpp")
-    .compile("wrapper");
-
-  println!("cargo:rustc-link-search={}", out_dir);
-  println!("cargo:rustc-link-lib=wrapper");
-  println!("cargo:rustc-link-lib=stdc++");
+  generators("bulletproof", "generators.rs");
+  generators("bulletproof_plus", "generators_plus.rs");
 }

coins/monero/c/wrapper.cpp

@@ -1,158 +0,0 @@
-#include <mutex>
-
-#include "device/device_default.hpp"
-
-#include "ringct/bulletproofs.h"
-#include "ringct/rctSigs.h"
-
-typedef std::lock_guard<std::mutex> lock;
-
-std::mutex rng_mutex;
-uint8_t rng_entropy[64];
-
-extern "C" {
-  void rng(uint8_t* seed) {
-    // Set the first half to the seed
-    memcpy(rng_entropy, seed, 32);
-    // Set the second half to the hash of a DST to ensure a lack of collisions
-    crypto::cn_fast_hash("RNG_entropy_seed", 16, (char*) &rng_entropy[32]);
-  }
-}
-
-extern "C" void monero_wide_reduce(uint8_t* value);
-namespace crypto {
-  void generate_random_bytes_not_thread_safe(size_t n, void* value) {
-    size_t written = 0;
-    while (written != n) {
-      uint8_t hash[32];
-      crypto::cn_fast_hash(rng_entropy, 64, (char*) hash);
-      // Step the RNG by setting the latter half to the most recent result
-      // Does not leak the RNG, even if the values are leaked (which they are
-      // expected to be) due to the first half remaining constant and
-      // undisclosed
-      memcpy(&rng_entropy[32], hash, 32);
-
-      size_t next = n - written;
-      if (next > 32) {
-        next = 32;
-      }
-      memcpy(&((uint8_t*) value)[written], hash, next);
-      written += next;
-    }
-  }
-
-  void random32_unbiased(unsigned char *bytes) {
-    uint8_t value[64];
-    generate_random_bytes_not_thread_safe(64, value);
-    monero_wide_reduce(value);
-    memcpy(bytes, value, 32);
-  }
-}
-
-extern "C" {
-  void c_hash_to_point(uint8_t* point) {
-    rct::key key_point;
-    ge_p3 e_p3;
-    memcpy(key_point.bytes, point, 32);
-    rct::hash_to_p3(e_p3, key_point);
-    ge_p3_tobytes(point, &e_p3);
-  }
-
-  uint8_t* c_generate_bp(uint8_t* seed, uint8_t len, uint64_t* a, uint8_t* m) {
-    lock guard(rng_mutex);
-    rng(seed);
-
-    rct::keyV masks;
-    std::vector<uint64_t> amounts;
-    masks.resize(len);
-    amounts.resize(len);
-    for (uint8_t i = 0; i < len; i++) {
-      memcpy(masks[i].bytes, m + (i * 32), 32);
-      amounts[i] = a[i];
-    }
-
-    rct::Bulletproof bp = rct::bulletproof_PROVE(amounts, masks);
-
-    std::stringstream ss;
-    binary_archive<true> ba(ss);
-    ::serialization::serialize(ba, bp);
-    uint8_t* res = (uint8_t*) calloc(ss.str().size(), 1);
-    memcpy(res, ss.str().data(), ss.str().size());
-    return res;
-  }
-
-  bool c_verify_bp(
-    uint8_t* seed,
-    uint s_len,
-    uint8_t* s,
-    uint8_t c_len,
-    uint8_t* c
-  ) {
-    // BPs are batch verified which use RNG based weights to ensure individual
-    // integrity
-    // That's why this must also have control over RNG, to prevent interrupting
-    // multisig signing while not using known seeds. Considering this doesn't
-    // actually define a batch, and it's only verifying a single BP,
-    // it'd probably be fine, but...
-    lock guard(rng_mutex);
-    rng(seed);
-
-    rct::Bulletproof bp;
-    std::stringstream ss;
-    std::string str;
-    str.assign((char*) s, (size_t) s_len);
-    ss << str;
-    binary_archive<false> ba(ss);
-    ::serialization::serialize(ba, bp);
-    if (!ss.good()) {
-      return false;
-    }
-
-    bp.V.resize(c_len);
-    for (uint8_t i = 0; i < c_len; i++) {
-      memcpy(bp.V[i].bytes, &c[i * 32], 32);
-    }
-
-    try { return rct::bulletproof_VERIFY(bp); } catch(...) { return false; }
-  }
-
-  bool c_verify_clsag(
-    uint s_len,
-    uint8_t* s,
-    uint8_t k_len,
-    uint8_t* k,
-    uint8_t* I,
-    uint8_t* p,
-    uint8_t* m
-  ) {
-    rct::clsag clsag;
-    std::stringstream ss;
-    std::string str;
-    str.assign((char*) s, (size_t) s_len);
-    ss << str;
-    binary_archive<false> ba(ss);
-    ::serialization::serialize(ba, clsag);
-    if (!ss.good()) {
-      return false;
-    }
-
-    rct::ctkeyV keys;
-    keys.resize(k_len);
-    for (uint8_t i = 0; i < k_len; i++) {
-      memcpy(keys[i].dest.bytes, &k[(i * 2) * 32], 32);
-      memcpy(keys[i].mask.bytes, &k[((i * 2) + 1) * 32], 32);
-    }
-
-    memcpy(clsag.I.bytes, I, 32);
-
-    rct::key pseudo_out;
-    memcpy(pseudo_out.bytes, p, 32);
-
-    rct::key msg;
-    memcpy(msg.bytes, m, 32);
-
-    try {
-      return verRctCLSAGSimple(msg, clsag, keys, pseudo_out);
-    } catch(...) { return false; }
-  }
-}

coins/monero/generators/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "monero-generators"
+version = "0.3.0"
+description = "Monero's hash_to_point and generators"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/coins/monero/generators"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+edition = "2021"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[dependencies]
+std-shims = { path = "../../../common/std-shims", version = "0.1", default-features = false }
+
+subtle = { version = "^2.4", default-features = false }
+
+sha3 = { version = "0.10", default-features = false }
+
+curve25519-dalek = { version = "3", default-features = false }
+
+group = { version = "0.13", default-features = false }
+dalek-ff-group = { path = "../../../crypto/dalek-ff-group", version = "0.3" }
+
+[features]
+std = ["std-shims/std"]
+default = ["std"]

coins/monero/generators/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022-2023 Luke Parker
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

coins/monero/generators/README.md

@@ -0,0 +1,7 @@
+# Monero Generators
+
+Generators used by Monero in both its Pedersen commitments and Bulletproofs(+).
+An implementation of Monero's `ge_fromfe_frombytes_vartime`, simply called
+`hash_to_point` here, is included, as needed to generate generators.
+
+This library is usable under no_std when the `alloc` feature is enabled.

coins/monero/generators/src/hash_to_point.rs

@@ -0,0 +1,52 @@
+use subtle::ConditionallySelectable;
+
+use curve25519_dalek::edwards::{EdwardsPoint, CompressedEdwardsY};
+
+use group::ff::{Field, PrimeField};
+use dalek_ff_group::FieldElement;
+
+use crate::hash;
+
+/// Monero's hash to point function, as named `ge_fromfe_frombytes_vartime`.
+#[allow(clippy::many_single_char_names)]
+pub fn hash_to_point(bytes: [u8; 32]) -> EdwardsPoint {
+  #[allow(non_snake_case, clippy::unreadable_literal)]
+  let A = FieldElement::from(486662u64);
+
+  let v = FieldElement::from_square(hash(&bytes)).double();
+  let w = v + FieldElement::ONE;
+  let x = w.square() + (-A.square() * v);
+
+  // This isn't the complete X, yet its initial value
+  // We don't calculate the full X, and instead solely calculate Y, letting dalek reconstruct X
+  // While inefficient, it solves API boundaries and reduces the amount of work done here
+  #[allow(non_snake_case)]
+  let X = {
+    let u = w;
+    let v = x;
+    let v3 = v * v * v;
+    let uv3 = u * v3;
+    let v7 = v3 * v3 * v;
+    let uv7 = u * v7;
+    uv3 * uv7.pow((-FieldElement::from(5u8)) * FieldElement::from(8u8).invert().unwrap())
+  };
+  let x = X.square() * x;
+
+  let y = w - x;
+  let non_zero_0 = !y.is_zero();
+  let y_if_non_zero_0 = w + x;
+  let sign = non_zero_0 & (!y_if_non_zero_0.is_zero());
+
+  let mut z = -A;
+  z *= FieldElement::conditional_select(&v, &FieldElement::from(1u8), sign);
+  #[allow(non_snake_case)]
+  let Z = z + w;
+  #[allow(non_snake_case)]
+  let mut Y = z - w;
+
+  Y *= Z.invert().unwrap();
+  let mut bytes = Y.to_repr();
+  bytes[31] |= sign.unwrap_u8() << 7;
+
+  CompressedEdwardsY(bytes).decompress().unwrap().mul_by_cofactor()
+}

coins/monero/generators/src/lib.rs

@@ -0,0 +1,80 @@
+//! Generators used by Monero in both its Pedersen commitments and Bulletproofs(+).
+//!
+//! An implementation of Monero's `ge_fromfe_frombytes_vartime`, simply called
+//! `hash_to_point` here, is included, as needed to generate generators.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use std_shims::sync::OnceLock;
+
+use sha3::{Digest, Keccak256};
+
+use curve25519_dalek::edwards::{EdwardsPoint as DalekPoint, CompressedEdwardsY};
+
+use group::{Group, GroupEncoding};
+use dalek_ff_group::EdwardsPoint;
+
+mod varint;
+use varint::write_varint;
+
+mod hash_to_point;
+pub use hash_to_point::hash_to_point;
+
+fn hash(data: &[u8]) -> [u8; 32] {
+  Keccak256::digest(data).into()
+}
+
+static H_CELL: OnceLock<DalekPoint> = OnceLock::new();
+/// Monero's alternate generator `H`, used for amounts in Pedersen commitments.
+#[allow(non_snake_case)]
+pub fn H() -> DalekPoint {
+  *H_CELL.get_or_init(|| {
+    CompressedEdwardsY(hash(&EdwardsPoint::generator().to_bytes()))
+      .decompress()
+      .unwrap()
+      .mul_by_cofactor()
+  })
+}
+
+static H_POW_2_CELL: OnceLock<[DalekPoint; 64]> = OnceLock::new();
+/// Monero's alternate generator `H`, multiplied by 2**i for i in 1 ..= 64.
+#[allow(non_snake_case)]
+pub fn H_pow_2() -> &'static [DalekPoint; 64] {
+  H_POW_2_CELL.get_or_init(|| {
+    let mut res = [H(); 64];
+    for i in 1 .. 64 {
+      res[i] = res[i - 1] + res[i - 1];
+    }
+    res
+  })
+}
+
+const MAX_M: usize = 16;
+const N: usize = 64;
+const MAX_MN: usize = MAX_M * N;
+
+/// Container struct for Bulletproofs(+) generators.
+#[allow(non_snake_case)]
+pub struct Generators {
+  pub G: [EdwardsPoint; MAX_MN],
+  pub H: [EdwardsPoint; MAX_MN],
+}
+
+/// Generate generators as needed for Bulletproofs(+), as Monero does.
+pub fn bulletproofs_generators(dst: &'static [u8]) -> Generators {
+  let mut res =
+    Generators { G: [EdwardsPoint::identity(); MAX_MN], H: [EdwardsPoint::identity(); MAX_MN] };
+  for i in 0 .. MAX_MN {
+    let i = 2 * i;
+
+    let mut even = H().compress().to_bytes().to_vec();
+    even.extend(dst);
+    let mut odd = even.clone();
+
+    write_varint(&i.try_into().unwrap(), &mut even).unwrap();
+    write_varint(&(i + 1).try_into().unwrap(), &mut odd).unwrap();
+    res.H[i / 2] = EdwardsPoint(hash_to_point(hash(&even)));
+    res.G[i / 2] = EdwardsPoint(hash_to_point(hash(&odd)));
+  }
+  res
+}

coins/monero/generators/src/varint.rs

@@ -0,0 +1,18 @@
+use std_shims::io::{self, Write};
+
+const VARINT_CONTINUATION_MASK: u8 = 0b1000_0000;
+
+#[allow(clippy::trivially_copy_pass_by_ref)] // &u64 is needed for API consistency
+pub(crate) fn write_varint<W: Write>(varint: &u64, w: &mut W) -> io::Result<()> {
+  let mut varint = *varint;
+  while {
+    let mut b = u8::try_from(varint & u64::from(!VARINT_CONTINUATION_MASK)).unwrap();
+    varint >>= 7;
+    if varint != 0 {
+      b |= VARINT_CONTINUATION_MASK;
+    }
+    w.write_all(&[b])?;
+    varint != 0
+  } {}
+  Ok(())
+}

coins/monero/src/bin/reserialize_chain.rs

@@ -0,0 +1,155 @@
+use std::sync::Arc;
+
+use serde::Deserialize;
+use serde_json::json;
+
+use monero_serai::{
+  transaction::Transaction,
+  block::Block,
+  rpc::{Rpc, HttpRpc},
+};
+
+use tokio::task::JoinHandle;
+
+async fn check_block(rpc: Arc<Rpc<HttpRpc>>, block_i: usize) {
+  let hash = rpc.get_block_hash(block_i).await.expect("couldn't get block {block_i}'s hash");
+
+  // TODO: Grab the JSON to also check it was deserialized correctly
+  #[derive(Deserialize, Debug)]
+  struct BlockResponse {
+    blob: String,
+  }
+  let res: BlockResponse = rpc
+    .json_rpc_call("get_block", Some(json!({ "hash": hex::encode(hash) })))
+    .await
+    .expect("couldn't get block {block} via block.hash()");
+
+  let blob = hex::decode(res.blob).expect("node returned non-hex block");
+  let block = Block::read(&mut blob.as_slice()).expect("couldn't deserialize block {block_i}");
+  assert_eq!(block.hash(), hash, "hash differs");
+  assert_eq!(block.serialize(), blob, "serialization differs");
+
+  let txs_len = 1 + block.txs.len();
+
+  if !block.txs.is_empty() {
+    #[derive(Deserialize, Debug)]
+    struct TransactionResponse {
+      tx_hash: String,
+      as_hex: String,
+    }
+    #[derive(Deserialize, Debug)]
+    struct TransactionsResponse {
+      #[serde(default)]
+      missed_tx: Vec<String>,
+      txs: Vec<TransactionResponse>,
+    }
+
+    let mut hashes_hex = block.txs.iter().map(hex::encode).collect::<Vec<_>>();
+    let mut all_txs = vec![];
+    while !hashes_hex.is_empty() {
+      let txs: TransactionsResponse = rpc
+        .rpc_call(
+          "get_transactions",
+          Some(json!({
+            "txs_hashes": hashes_hex.drain(.. hashes_hex.len().min(100)).collect::<Vec<_>>(),
+          })),
+        )
+        .await
+        .expect("couldn't call get_transactions");
+      assert!(txs.missed_tx.is_empty());
+      all_txs.extend(txs.txs);
+    }
+
+    for (tx_hash, tx_res) in block.txs.into_iter().zip(all_txs.into_iter()) {
+      assert_eq!(
+        tx_res.tx_hash,
+        hex::encode(tx_hash),
+        "node returned a transaction with different hash"
+      );
+
+      let tx = Transaction::read(
+        &mut hex::decode(&tx_res.as_hex).expect("node returned non-hex transaction").as_slice(),
+      )
+      .expect("couldn't deserialize transaction");
+
+      assert_eq!(
+        hex::encode(tx.serialize()),
+        tx_res.as_hex,
+        "Transaction serialization was different"
+      );
+      assert_eq!(tx.hash(), tx_hash, "Transaction hash was different");
+    }
+  }
+
+  println!("Deserialized, hashed, and reserialized {block_i} with {} TXs", txs_len);
+}
+
+#[tokio::main]
+async fn main() {
+  let args = std::env::args().collect::<Vec<String>>();
+
+  // Read start block as the first arg
+  let mut block_i = args[1].parse::<usize>().expect("invalid start block");
+
+  // How many blocks to work on at once
+  let async_parallelism: usize =
+    args.get(2).unwrap_or(&"8".to_string()).parse::<usize>().expect("invalid parallelism argument");
+
+  // Read further args as RPC URLs
+  let default_nodes = vec![
+    "http://xmr-node.cakewallet.com:18081".to_string(),
+    "https://node.sethforprivacy.com".to_string(),
+  ];
+  let mut specified_nodes = vec![];
+  {
+    let mut i = 0;
+    loop {
+      let Some(node) = args.get(3 + i) else { break };
+      specified_nodes.push(node.clone());
+      i += 1;
+    }
+  }
+  let nodes = if specified_nodes.is_empty() { default_nodes } else { specified_nodes };
+
+  let rpc = |url: String| {
+    HttpRpc::new(url.clone())
+      .unwrap_or_else(|_| panic!("couldn't create HttpRpc connected to {url}"))
+  };
+  let main_rpc = rpc(nodes[0].clone());
+  let mut rpcs = vec![];
+  for i in 0 .. async_parallelism {
+    rpcs.push(Arc::new(rpc(nodes[i % nodes.len()].clone())));
+  }
+
+  let mut rpc_i = 0;
+  let mut handles: Vec<JoinHandle<()>> = vec![];
+  let mut height = 0;
+  loop {
+    let new_height = main_rpc.get_height().await.expect("couldn't call get_height");
+    if new_height == height {
+      break;
+    }
+    height = new_height;
+
+    while block_i < height {
+      if handles.len() >= async_parallelism {
+        // Guarantee one handle is complete
+        handles.swap_remove(0).await.unwrap();
+
+        // Remove all of the finished handles
+        let mut i = 0;
+        while i < handles.len() {
+          if handles[i].is_finished() {
+            handles.swap_remove(i).await.unwrap();
+            continue;
+          }
+          i += 1;
+        }
+      }
+
+      handles.push(tokio::spawn(check_block(rpcs[rpc_i].clone(), block_i)));
+      rpc_i = (rpc_i + 1) % rpcs.len();
+      block_i += 1;
+    }
+  }
+}

coins/monero/src/block.rs

@@ -1,19 +1,31 @@
-use crate::{
-  serialize::*,
-  transaction::Transaction
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
 };
 
-#[derive(Clone, PartialEq, Debug)]
+use crate::{
+  hash,
+  merkle::merkle_root,
+  serialize::*,
+  transaction::{Input, Transaction},
+};
+
+const CORRECT_BLOCK_HASH_202612: [u8; 32] =
+  hex_literal::hex!("426d16cff04c71f8b16340b722dc4010a2dd3831c22041431f772547ba6e331a");
+const EXISTING_BLOCK_HASH_202612: [u8; 32] =
+  hex_literal::hex!("bbd604d2ba11ba27935e006ed39c9bfdd99b76bf4a50654bc1e1e61217962698");
+
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct BlockHeader {
   pub major_version: u64,
   pub minor_version: u64,
   pub timestamp: u64,
   pub previous: [u8; 32],
-  pub nonce: u32
+  pub nonce: u32,
 }
 
 impl BlockHeader {
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
     write_varint(&self.major_version, w)?;
     write_varint(&self.minor_version, w)?;
     write_varint(&self.timestamp, w)?;
@@ -21,30 +33,41 @@ impl BlockHeader {
     w.write_all(&self.nonce.to_le_bytes())
   }
 
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<BlockHeader> {
-    Ok(
-      BlockHeader {
-        major_version: read_varint(r)?,
-        minor_version: read_varint(r)?,
-        timestamp: read_varint(r)?,
-        previous: { let mut previous = [0; 32]; r.read_exact(&mut previous)?; previous },
-        nonce: { let mut nonce = [0; 4]; r.read_exact(&mut nonce)?; u32::from_le_bytes(nonce) }
-      }
-    )
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self {
+      major_version: read_varint(r)?,
+      minor_version: read_varint(r)?,
+      timestamp: read_varint(r)?,
+      previous: read_bytes(r)?,
+      nonce: read_bytes(r).map(u32::from_le_bytes)?,
+    })
   }
 }
 
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct Block {
   pub header: BlockHeader,
   pub miner_tx: Transaction,
-  pub txs: Vec<[u8; 32]>
+  pub txs: Vec<[u8; 32]>,
 }
 
 impl Block {
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
-    self.header.serialize(w)?;
-    self.miner_tx.serialize(w)?;
+  pub fn number(&self) -> usize {
+    match self.miner_tx.prefix.inputs.get(0) {
+      Some(Input::Gen(number)) => (*number).try_into().unwrap(),
+      _ => panic!("invalid block, miner TX didn't have a Input::Gen"),
+    }
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.header.write(w)?;
+    self.miner_tx.write(w)?;
     write_varint(&self.txs.len().try_into().unwrap(), w)?;
     for tx in &self.txs {
       w.write_all(tx)?;
@@ -52,15 +75,42 @@ impl Block {
     Ok(())
   }
 
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<Block> {
-    Ok(
-      Block {
-        header: BlockHeader::deserialize(r)?,
-        miner_tx: Transaction::deserialize(r)?,
-        txs: (0 .. read_varint(r)?).map(
-          |_| { let mut tx = [0; 32]; r.read_exact(&mut tx).map(|_| tx) }
-        ).collect::<Result<_, _>>()?
-      }
-    )
+  fn tx_merkle_root(&self) -> [u8; 32] {
+    merkle_root(self.miner_tx.hash(), &self.txs)
+  }
+
+  fn serialize_hashable(&self) -> Vec<u8> {
+    let mut blob = self.header.serialize();
+    blob.extend_from_slice(&self.tx_merkle_root());
+    write_varint(&(1 + u64::try_from(self.txs.len()).unwrap()), &mut blob).unwrap();
+
+    let mut out = Vec::with_capacity(8 + blob.len());
+    write_varint(&u64::try_from(blob.len()).unwrap(), &mut out).unwrap();
+    out.append(&mut blob);
+
+    out
+  }
+
+  pub fn hash(&self) -> [u8; 32] {
+    let hash = hash(&self.serialize_hashable());
+    if hash == CORRECT_BLOCK_HASH_202612 {
+      return EXISTING_BLOCK_HASH_202612;
+    };
+
+    hash
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self {
+      header: BlockHeader::read(r)?,
+      miner_tx: Transaction::read(r)?,
+      txs: (0 .. read_varint(r)?).map(|_| read_bytes(r)).collect::<Result<_, _>>()?,
+    })
   }
 }

coins/monero/src/frost.rs

@@ -1,76 +0,0 @@
-use std::io::Read;
-
-use thiserror::Error;
-use rand_core::{RngCore, CryptoRng};
-
-use curve25519_dalek::{scalar::Scalar, edwards::EdwardsPoint};
-
-use group::{Group, GroupEncoding};
-
-use transcript::{Transcript, RecommendedTranscript};
-use dalek_ff_group as dfg;
-use dleq::{Generators, DLEqProof};
-
-#[derive(Clone, Error, Debug)]
-pub enum MultisigError {
-  #[error("internal error ({0})")]
-  InternalError(String),
-  #[error("invalid discrete log equality proof")]
-  InvalidDLEqProof(u16),
-  #[error("invalid key image {0}")]
-  InvalidKeyImage(u16)
-}
-
-fn transcript() -> RecommendedTranscript {
-  RecommendedTranscript::new(b"monero_key_image_dleq")
-}
-
-#[allow(non_snake_case)]
-pub(crate) fn write_dleq<R: RngCore + CryptoRng>(
-  rng: &mut R,
-  H: EdwardsPoint,
-  x: Scalar
-) -> Vec<u8> {
-  let mut res = Vec::with_capacity(64);
-  DLEqProof::prove(
-    rng,
-    // Doesn't take in a larger transcript object due to the usage of this
-    // Every prover would immediately write their own DLEq proof, when they can only do so in
-    // the proper order if they want to reach consensus
-    // It'd be a poor API to have CLSAG define a new transcript solely to pass here, just to try to
-    // merge later in some form, when it should instead just merge xH (as it does)
-    &mut transcript(),
-    Generators::new(dfg::EdwardsPoint::generator(), dfg::EdwardsPoint(H)),
-    dfg::Scalar(x)
-  ).serialize(&mut res).unwrap();
-  res
-}
-
-#[allow(non_snake_case)]
-pub(crate) fn read_dleq<Re: Read>(
-  serialized: &mut Re,
-  H: EdwardsPoint,
-  l: u16,
-  xG: dfg::EdwardsPoint
-) -> Result<dfg::EdwardsPoint, MultisigError> {
-  let mut bytes = [0; 32];
-  serialized.read_exact(&mut bytes).map_err(|_| MultisigError::InvalidDLEqProof(l))?;
-  // dfg ensures the point is torsion free
-  let xH = Option::<dfg::EdwardsPoint>::from(
-    dfg::EdwardsPoint::from_bytes(&bytes)).ok_or(MultisigError::InvalidDLEqProof(l)
-  )?;
-  // Ensure this is a canonical point
-  if xH.to_bytes() != bytes {
-    Err(MultisigError::InvalidDLEqProof(l))?;
-  }
-
-  DLEqProof::<dfg::EdwardsPoint>::deserialize(
-    serialized
-  ).map_err(|_| MultisigError::InvalidDLEqProof(l))?.verify(
-    &mut transcript(),
-    Generators::new(dfg::EdwardsPoint::generator(), dfg::EdwardsPoint(H)),
-    (xG, xH)
-  ).map_err(|_| MultisigError::InvalidDLEqProof(l))?;
-
-  Ok(xH)
-}

coins/monero/src/lib.rs

@@ -1,100 +1,178 @@
-use std::slice;
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+#![cfg_attr(not(feature = "std"), no_std)]
+
+#[cfg(not(feature = "std"))]
+#[macro_use]
+extern crate alloc;
+
+use std_shims::{sync::OnceLock, io};
 
-use lazy_static::lazy_static;
 use rand_core::{RngCore, CryptoRng};
 
-use subtle::ConstantTimeEq;
+use zeroize::{Zeroize, ZeroizeOnDrop};
 
-use tiny_keccak::{Hasher, Keccak};
+use sha3::{Digest, Keccak256};
 
-use curve25519_dalek::{
-  constants::ED25519_BASEPOINT_TABLE,
-  scalar::Scalar,
-  edwards::{EdwardsPoint, EdwardsBasepointTable, CompressedEdwardsY}
-};
+use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, scalar::Scalar, edwards::EdwardsPoint};
 
-#[cfg(feature = "multisig")]
-pub mod frost;
+pub use monero_generators::H;
+
+mod merkle;
 
 mod serialize;
+use serialize::{read_byte, read_u16};
 
+/// RingCT structs and functionality.
 pub mod ringct;
+use ringct::RctType;
 
+/// Transaction structs.
 pub mod transaction;
+/// Block structs.
 pub mod block;
 
+/// Monero daemon RPC interface.
 pub mod rpc;
+/// Wallet functionality, enabling scanning and sending transactions.
 pub mod wallet;
 
 #[cfg(test)]
 mod tests;
 
-lazy_static! {
-  static ref H: EdwardsPoint = CompressedEdwardsY(
-    hex::decode("8b655970153799af2aeadc9ff1add0ea6c7251d54154cfa92c173a0dd39c1f94").unwrap().try_into().unwrap()
-  ).decompress().unwrap();
-  static ref H_TABLE: EdwardsBasepointTable = EdwardsBasepointTable::create(&*H);
+static INV_EIGHT_CELL: OnceLock<Scalar> = OnceLock::new();
+#[allow(non_snake_case)]
+pub(crate) fn INV_EIGHT() -> Scalar {
+  *INV_EIGHT_CELL.get_or_init(|| Scalar::from(8u8).invert())
 }
 
-// Function from libsodium our subsection of Monero relies on. Implementing it here means we don't
-// need to link against libsodium
-#[no_mangle]
-unsafe extern "C" fn crypto_verify_32(a: *const u8, b: *const u8) -> isize {
-  isize::from(
-    slice::from_raw_parts(a, 32).ct_eq(slice::from_raw_parts(b, 32)).unwrap_u8()
-  ) - 1
+/// Monero protocol version.
+///
+/// v15 is omitted as v15 was simply v14 and v16 being active at the same time, with regards to the
+/// transactions supported. Accordingly, v16 should be used during v15.
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
+#[allow(non_camel_case_types)]
+pub enum Protocol {
+  v14,
+  v16,
+  Custom { ring_len: usize, bp_plus: bool, optimal_rct_type: RctType },
 }
 
-// Offer a wide reduction to C. Our seeded RNG prevented Monero from defining an unbiased scalar
-// generation function, and in order to not use Monero code (which would require propagating its
-// license), the function was rewritten. It was rewritten with wide reduction, instead of rejection
-// sampling however, hence the need for this function
-#[no_mangle]
-unsafe extern "C" fn monero_wide_reduce(value: *mut u8) {
-  let res = Scalar::from_bytes_mod_order_wide(
-    std::slice::from_raw_parts(value, 64).try_into().unwrap()
-  );
-  for (i, b) in res.to_bytes().iter().enumerate() {
-    value.add(i).write(*b);
+impl Protocol {
+  /// Amount of ring members under this protocol version.
+  pub const fn ring_len(&self) -> usize {
+    match self {
+      Self::v14 => 11,
+      Self::v16 => 16,
+      Self::Custom { ring_len, .. } => *ring_len,
+    }
+  }
+
+  /// Whether or not the specified version uses Bulletproofs or Bulletproofs+.
+  ///
+  /// This method will likely be reworked when versions not using Bulletproofs at all are added.
+  pub const fn bp_plus(&self) -> bool {
+    match self {
+      Self::v14 => false,
+      Self::v16 => true,
+      Self::Custom { bp_plus, .. } => *bp_plus,
+    }
+  }
+
+  // TODO: Make this an Option when we support pre-RCT protocols
+  pub const fn optimal_rct_type(&self) -> RctType {
+    match self {
+      Self::v14 => RctType::Clsag,
+      Self::v16 => RctType::BulletproofsPlus,
+      Self::Custom { optimal_rct_type, .. } => *optimal_rct_type,
+    }
+  }
+
+  pub(crate) fn write<W: io::Write>(&self, w: &mut W) -> io::Result<()> {
+    match self {
+      Self::v14 => w.write_all(&[0, 14]),
+      Self::v16 => w.write_all(&[0, 16]),
+      Self::Custom { ring_len, bp_plus, optimal_rct_type } => {
+        // Custom, version 0
+        w.write_all(&[1, 0])?;
+        w.write_all(&u16::try_from(*ring_len).unwrap().to_le_bytes())?;
+        w.write_all(&[u8::from(*bp_plus)])?;
+        w.write_all(&[optimal_rct_type.to_byte()])
+      }
+    }
+  }
+
+  pub(crate) fn read<R: io::Read>(r: &mut R) -> io::Result<Self> {
+    Ok(match read_byte(r)? {
+      // Monero protocol
+      0 => match read_byte(r)? {
+        14 => Self::v14,
+        16 => Self::v16,
+        _ => Err(io::Error::new(io::ErrorKind::Other, "unrecognized monero protocol"))?,
+      },
+      // Custom
+      1 => match read_byte(r)? {
+        0 => Self::Custom {
+          ring_len: read_u16(r)?.into(),
+          bp_plus: match read_byte(r)? {
+            0 => false,
+            1 => true,
+            _ => Err(io::Error::new(io::ErrorKind::Other, "invalid bool serialization"))?,
+          },
+          optimal_rct_type: RctType::from_byte(read_byte(r)?)
+            .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "invalid RctType serialization"))?,
+        },
+        _ => {
+          Err(io::Error::new(io::ErrorKind::Other, "unrecognized custom protocol serialization"))?
+        }
+      },
+      _ => Err(io::Error::new(io::ErrorKind::Other, "unrecognized protocol serialization"))?,
+    })
   }
 }
 
+/// Transparent structure representing a Pedersen commitment's contents.
 #[allow(non_snake_case)]
-#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
 pub struct Commitment {
   pub mask: Scalar,
-  pub amount: u64
+  pub amount: u64,
 }
 
 impl Commitment {
-  pub fn zero() -> Commitment {
-    Commitment { mask: Scalar::one(), amount: 0}
+  /// A commitment to zero, defined with a mask of 1 (as to not be the identity).
+  pub fn zero() -> Self {
+    Self { mask: Scalar::one(), amount: 0 }
   }
 
-  pub fn new(mask: Scalar, amount: u64) -> Commitment {
-    Commitment { mask, amount }
+  pub fn new(mask: Scalar, amount: u64) -> Self {
+    Self { mask, amount }
   }
 
+  /// Calculate a Pedersen commitment, as a point, from the transparent structure.
   pub fn calculate(&self) -> EdwardsPoint {
-    (&self.mask * &ED25519_BASEPOINT_TABLE) + (&Scalar::from(self.amount) * &*H_TABLE)
+    (&self.mask * &ED25519_BASEPOINT_TABLE) + (Scalar::from(self.amount) * H())
   }
 }
 
-// Allows using a modern rand as dalek's is notoriously dated
+/// Support generating a random scalar using a modern rand, as dalek's is notoriously dated.
 pub fn random_scalar<R: RngCore + CryptoRng>(rng: &mut R) -> Scalar {
   let mut r = [0; 64];
   rng.fill_bytes(&mut r);
   Scalar::from_bytes_mod_order_wide(&r)
 }
 
-pub fn hash(data: &[u8]) -> [u8; 32] {
-  let mut keccak = Keccak::v256();
-  keccak.update(data);
-  let mut res = [0; 32];
-  keccak.finalize(&mut res);
-  res
+pub(crate) fn hash(data: &[u8]) -> [u8; 32] {
+  Keccak256::digest(data).into()
 }
 
+/// Hash the provided data to a scalar via keccak256(data) % l.
 pub fn hash_to_scalar(data: &[u8]) -> Scalar {
-  Scalar::from_bytes_mod_order(hash(&data))
+  let scalar = Scalar::from_bytes_mod_order(hash(data));
+  // Monero will explicitly error in this case
+  // This library acknowledges its practical impossibility of it occurring, and doesn't bother to
+  // code in logic to handle it. That said, if it ever occurs, something must happen in order to
+  // not generate/verify a proof we believe to be valid when it isn't
+  assert!(scalar != Scalar::zero(), "ZERO HASH: {data:?}");
+  scalar
 }

coins/monero/src/merkle.rs

@@ -0,0 +1,55 @@
+use std_shims::vec::Vec;
+
+use crate::hash;
+
+pub(crate) fn merkle_root(root: [u8; 32], leafs: &[[u8; 32]]) -> [u8; 32] {
+  match leafs.len() {
+    0 => root,
+    1 => hash(&[root, leafs[0]].concat()),
+    _ => {
+      let mut hashes = Vec::with_capacity(1 + leafs.len());
+      hashes.push(root);
+      hashes.extend(leafs);
+
+      // Monero preprocess this so the length is a power of 2
+      let mut high_pow_2 = 4; // 4 is the lowest value this can be
+      while high_pow_2 < hashes.len() {
+        high_pow_2 *= 2;
+      }
+      let low_pow_2 = high_pow_2 / 2;
+
+      // Merge right-most hashes until we're at the low_pow_2
+      {
+        let overage = hashes.len() - low_pow_2;
+        let mut rightmost = hashes.drain((low_pow_2 - overage) ..);
+        // This is true since we took overage from beneath and above low_pow_2, taking twice as
+        // many elements as overage
+        debug_assert_eq!(rightmost.len() % 2, 0);
+
+        let mut paired_hashes = Vec::with_capacity(overage);
+        while let Some(left) = rightmost.next() {
+          let right = rightmost.next().unwrap();
+          paired_hashes.push(hash(&[left.as_ref(), &right].concat()));
+        }
+        drop(rightmost);
+
+        hashes.extend(paired_hashes);
+        assert_eq!(hashes.len(), low_pow_2);
+      }
+
+      // Do a traditional pairing off
+      let mut new_hashes = Vec::with_capacity(hashes.len() / 2);
+      while hashes.len() > 1 {
+        let mut i = 0;
+        while i < hashes.len() {
+          new_hashes.push(hash(&[hashes[i], hashes[i + 1]].concat()));
+          i += 2;
+        }
+
+        hashes = new_hashes;
+        new_hashes = Vec::with_capacity(hashes.len() / 2);
+      }
+      hashes[0]
+    }
+  }
+}

coins/monero/src/ringct/borromean.rs

@@ -0,0 +1,102 @@
+use core::fmt::Debug;
+use std_shims::io::{self, Read, Write};
+
+use curve25519_dalek::edwards::EdwardsPoint;
+#[cfg(feature = "experimental")]
+use curve25519_dalek::{traits::Identity, scalar::Scalar};
+
+#[cfg(feature = "experimental")]
+use monero_generators::H_pow_2;
+#[cfg(feature = "experimental")]
+use crate::hash_to_scalar;
+use crate::serialize::*;
+
+/// 64 Borromean ring signatures.
+///
+/// This type keeps the data as raw bytes as Monero has some transactions with unreduced scalars in
+/// this field. While we could use `from_bytes_mod_order`, we'd then not be able to encode this
+/// back into it's original form.
+///
+/// Those scalars also have a custom reduction algorithm...
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct BorromeanSignatures {
+  pub s0: [[u8; 32]; 64],
+  pub s1: [[u8; 32]; 64],
+  pub ee: [u8; 32],
+}
+
+impl BorromeanSignatures {
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self { s0: read_array(read_bytes, r)?, s1: read_array(read_bytes, r)?, ee: read_bytes(r)? })
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    for s0 in &self.s0 {
+      w.write_all(s0)?;
+    }
+    for s1 in &self.s1 {
+      w.write_all(s1)?;
+    }
+    w.write_all(&self.ee)
+  }
+
+  #[cfg(feature = "experimental")]
+  fn verify(&self, keys_a: &[EdwardsPoint], keys_b: &[EdwardsPoint]) -> bool {
+    let mut transcript = [0; 2048];
+    for i in 0 .. 64 {
+      // TODO: These aren't the correct reduction
+      // TODO: Can either of these be tightened?
+      #[allow(non_snake_case)]
+      let LL = EdwardsPoint::vartime_double_scalar_mul_basepoint(
+        &Scalar::from_bytes_mod_order(self.ee),
+        &keys_a[i],
+        &Scalar::from_bytes_mod_order(self.s0[i]),
+      );
+      #[allow(non_snake_case)]
+      let LV = EdwardsPoint::vartime_double_scalar_mul_basepoint(
+        &hash_to_scalar(LL.compress().as_bytes()),
+        &keys_b[i],
+        &Scalar::from_bytes_mod_order(self.s1[i]),
+      );
+      transcript[i .. ((i + 1) * 32)].copy_from_slice(LV.compress().as_bytes());
+    }
+
+    // TODO: This isn't the correct reduction
+    // TODO: Can this be tightened to from_canonical_bytes?
+    hash_to_scalar(&transcript) == Scalar::from_bytes_mod_order(self.ee)
+  }
+}
+
+/// A range proof premised on Borromean ring signatures.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct BorromeanRange {
+  pub sigs: BorromeanSignatures,
+  pub bit_commitments: [EdwardsPoint; 64],
+}
+
+impl BorromeanRange {
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self { sigs: BorromeanSignatures::read(r)?, bit_commitments: read_array(read_point, r)? })
+  }
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.sigs.write(w)?;
+    write_raw_vec(write_point, &self.bit_commitments, w)
+  }
+
+  #[cfg(feature = "experimental")]
+  #[must_use]
+  pub fn verify(&self, commitment: &EdwardsPoint) -> bool {
+    if &self.bit_commitments.iter().sum::<EdwardsPoint>() != commitment {
+      return false;
+    }
+
+    #[allow(non_snake_case)]
+    let H_pow_2 = H_pow_2();
+    let mut commitments_sub_one = [EdwardsPoint::identity(); 64];
+    for i in 0 .. 64 {
+      commitments_sub_one[i] = self.bit_commitments[i] - H_pow_2[i];
+    }
+
+    self.sigs.verify(&self.bit_commitments, &commitments_sub_one)
+  }
+}

coins/monero/src/ringct/bulletproofs.rs

@@ -1,161 +0,0 @@
-#![allow(non_snake_case)]
-
-use rand_core::{RngCore, CryptoRng};
-
-use curve25519_dalek::{scalar::Scalar, edwards::EdwardsPoint};
-
-use crate::{Commitment, wallet::TransactionError, serialize::*};
-
-pub(crate) const MAX_OUTPUTS: usize = 16;
-
-#[derive(Clone, PartialEq, Debug)]
-pub struct Bulletproofs {
-  pub A: EdwardsPoint,
-  pub S: EdwardsPoint,
-  pub T1: EdwardsPoint,
-  pub T2: EdwardsPoint,
-  pub taux: Scalar,
-  pub mu: Scalar,
-  pub L: Vec<EdwardsPoint>,
-  pub R: Vec<EdwardsPoint>,
-  pub a: Scalar,
-  pub b: Scalar,
-  pub t: Scalar
-}
-
-impl Bulletproofs {
-  pub(crate) fn fee_weight(outputs: usize) -> usize {
-    let proofs = 6 + usize::try_from(usize::BITS - (outputs - 1).leading_zeros()).unwrap();
-    let len = (9 + (2 * proofs)) * 32;
-
-    let mut clawback = 0;
-    let padded = 1 << (proofs - 6);
-    if padded > 2 {
-      const BP_BASE: usize = 368;
-      clawback = ((BP_BASE * padded) - len) * 4 / 5;
-    }
-
-    len + clawback
-  }
-
-  pub fn new<R: RngCore + CryptoRng>(rng: &mut R, outputs: &[Commitment]) -> Result<Bulletproofs, TransactionError> {
-    if outputs.len() > MAX_OUTPUTS {
-      return Err(TransactionError::TooManyOutputs)?;
-    }
-
-    let mut seed = [0; 32];
-    rng.fill_bytes(&mut seed);
-
-    let masks = outputs.iter().map(|commitment| commitment.mask.to_bytes()).collect::<Vec<_>>();
-    let amounts = outputs.iter().map(|commitment| commitment.amount).collect::<Vec<_>>();
-
-    let res;
-    unsafe {
-      #[link(name = "wrapper")]
-      extern "C" {
-        fn free(ptr: *const u8);
-        fn c_generate_bp(seed: *const u8, len: u8, amounts: *const u64, masks: *const [u8; 32]) -> *const u8;
-      }
-
-      let ptr = c_generate_bp(
-        seed.as_ptr(),
-        u8::try_from(outputs.len()).unwrap(),
-        amounts.as_ptr(),
-        masks.as_ptr()
-      );
-
-      let mut len = 6 * 32;
-      len += (2 * (1 + (usize::from(ptr.add(len).read()) * 32))) + (3 * 32);
-      res = Bulletproofs::deserialize(
-        // Wrap in a cursor to provide a mutable Reader
-        &mut std::io::Cursor::new(std::slice::from_raw_parts(ptr, len))
-      ).expect("Couldn't deserialize Bulletproofs from Monero");
-      free(ptr);
-    };
-
-    Ok(res)
-  }
-
-  #[must_use]
-  pub fn verify<R: RngCore + CryptoRng>(&self, rng: &mut R, commitments: &[EdwardsPoint]) -> bool {
-    if commitments.len() > 16 {
-      return false;
-    }
-
-    let mut seed = [0; 32];
-    rng.fill_bytes(&mut seed);
-
-    let mut serialized = Vec::with_capacity((9 + (2 * self.L.len())) * 32);
-    self.serialize(&mut serialized).unwrap();
-    let commitments: Vec<[u8; 32]> = commitments.iter().map(
-      |commitment| (commitment * Scalar::from(8u8).invert()).compress().to_bytes()
-    ).collect();
-
-    unsafe {
-      #[link(name = "wrapper")]
-      extern "C" {
-        fn c_verify_bp(
-          seed: *const u8,
-          serialized_len: usize,
-          serialized: *const u8,
-          commitments_len: u8,
-          commitments: *const [u8; 32]
-        ) -> bool;
-      }
-
-      c_verify_bp(
-        seed.as_ptr(),
-        serialized.len(),
-        serialized.as_ptr(),
-        u8::try_from(commitments.len()).unwrap(),
-        commitments.as_ptr()
-      )
-    }
-  }
-
-  fn serialize_core<
-    W: std::io::Write,
-    F: Fn(&[EdwardsPoint], &mut W) -> std::io::Result<()>
-  >(&self, w: &mut W, specific_write_vec: F) -> std::io::Result<()> {
-    write_point(&self.A, w)?;
-    write_point(&self.S, w)?;
-    write_point(&self.T1, w)?;
-    write_point(&self.T2, w)?;
-    write_scalar(&self.taux, w)?;
-    write_scalar(&self.mu, w)?;
-    specific_write_vec(&self.L, w)?;
-    specific_write_vec(&self.R, w)?;
-    write_scalar(&self.a, w)?;
-    write_scalar(&self.b, w)?;
-    write_scalar(&self.t, w)
-  }
-
-  pub fn signature_serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
-    self.serialize_core(w, |points, w| write_raw_vec(write_point, points, w))
-  }
-
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
-    self.serialize_core(w, |points, w| write_vec(write_point, points, w))
-  }
-
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<Bulletproofs> {
-    let bp = Bulletproofs {
-      A: read_point(r)?,
-      S: read_point(r)?,
-      T1: read_point(r)?,
-      T2: read_point(r)?,
-      taux: read_scalar(r)?,
-      mu: read_scalar(r)?,
-      L: read_vec(read_point, r)?,
-      R: read_vec(read_point, r)?,
-      a: read_scalar(r)?,
-      b: read_scalar(r)?,
-      t: read_scalar(r)?
-    };
-
-    if bp.L.len() != bp.R.len() {
-      Err(std::io::Error::new(std::io::ErrorKind::Other, "mismatched L/R len"))?;
-    }
-    Ok(bp)
-  }
-}

coins/monero/src/ringct/bulletproofs/core.rs

@@ -0,0 +1,151 @@
+use std_shims::{vec::Vec, sync::OnceLock};
+
+use rand_core::{RngCore, CryptoRng};
+
+use subtle::{Choice, ConditionallySelectable};
+
+use curve25519_dalek::edwards::EdwardsPoint as DalekPoint;
+
+use group::{ff::Field, Group};
+use dalek_ff_group::{Scalar, EdwardsPoint};
+
+use multiexp::multiexp as multiexp_const;
+
+pub(crate) use monero_generators::Generators;
+
+use crate::{INV_EIGHT as DALEK_INV_EIGHT, H as DALEK_H, Commitment, hash_to_scalar as dalek_hash};
+pub(crate) use crate::ringct::bulletproofs::scalar_vector::*;
+
+#[inline]
+pub(crate) fn INV_EIGHT() -> Scalar {
+  Scalar(DALEK_INV_EIGHT())
+}
+
+#[inline]
+pub(crate) fn H() -> EdwardsPoint {
+  EdwardsPoint(DALEK_H())
+}
+
+pub(crate) fn hash_to_scalar(data: &[u8]) -> Scalar {
+  Scalar(dalek_hash(data))
+}
+
+// Components common between variants
+pub(crate) const MAX_M: usize = 16;
+pub(crate) const LOG_N: usize = 6; // 2 << 6 == N
+pub(crate) const N: usize = 64;
+
+pub(crate) fn prove_multiexp(pairs: &[(Scalar, EdwardsPoint)]) -> EdwardsPoint {
+  multiexp_const(pairs) * INV_EIGHT()
+}
+
+pub(crate) fn vector_exponent(
+  generators: &Generators,
+  a: &ScalarVector,
+  b: &ScalarVector,
+) -> EdwardsPoint {
+  debug_assert_eq!(a.len(), b.len());
+  (a * &generators.G[.. a.len()]) + (b * &generators.H[.. b.len()])
+}
+
+pub(crate) fn hash_cache(cache: &mut Scalar, mash: &[[u8; 32]]) -> Scalar {
+  let slice =
+    &[cache.to_bytes().as_ref(), mash.iter().copied().flatten().collect::<Vec<_>>().as_ref()]
+      .concat();
+  *cache = hash_to_scalar(slice);
+  *cache
+}
+
+pub(crate) fn MN(outputs: usize) -> (usize, usize, usize) {
+  let mut logM = 0;
+  let mut M;
+  while {
+    M = 1 << logM;
+    (M <= MAX_M) && (M < outputs)
+  } {
+    logM += 1;
+  }
+
+  (logM + LOG_N, M, M * N)
+}
+
+pub(crate) fn bit_decompose(commitments: &[Commitment]) -> (ScalarVector, ScalarVector) {
+  let (_, M, MN) = MN(commitments.len());
+
+  let sv = commitments.iter().map(|c| Scalar::from(c.amount)).collect::<Vec<_>>();
+  let mut aL = ScalarVector::new(MN);
+  let mut aR = ScalarVector::new(MN);
+
+  for j in 0 .. M {
+    for i in (0 .. N).rev() {
+      let bit =
+        if j < sv.len() { Choice::from((sv[j][i / 8] >> (i % 8)) & 1) } else { Choice::from(0) };
+      aL.0[(j * N) + i] = Scalar::conditional_select(&Scalar::ZERO, &Scalar::ONE, bit);
+      aR.0[(j * N) + i] = Scalar::conditional_select(&-Scalar::ONE, &Scalar::ZERO, bit);
+    }
+  }
+
+  (aL, aR)
+}
+
+pub(crate) fn hash_commitments<C: IntoIterator<Item = DalekPoint>>(
+  commitments: C,
+) -> (Scalar, Vec<EdwardsPoint>) {
+  let V = commitments.into_iter().map(|c| EdwardsPoint(c) * INV_EIGHT()).collect::<Vec<_>>();
+  (hash_to_scalar(&V.iter().flat_map(|V| V.compress().to_bytes()).collect::<Vec<_>>()), V)
+}
+
+pub(crate) fn alpha_rho<R: RngCore + CryptoRng>(
+  rng: &mut R,
+  generators: &Generators,
+  aL: &ScalarVector,
+  aR: &ScalarVector,
+) -> (Scalar, EdwardsPoint) {
+  let ar = Scalar::random(rng);
+  (ar, (vector_exponent(generators, aL, aR) + (EdwardsPoint::generator() * ar)) * INV_EIGHT())
+}
+
+pub(crate) fn LR_statements(
+  a: &ScalarVector,
+  G_i: &[EdwardsPoint],
+  b: &ScalarVector,
+  H_i: &[EdwardsPoint],
+  cL: Scalar,
+  U: EdwardsPoint,
+) -> Vec<(Scalar, EdwardsPoint)> {
+  let mut res = a
+    .0
+    .iter()
+    .copied()
+    .zip(G_i.iter().copied())
+    .chain(b.0.iter().copied().zip(H_i.iter().copied()))
+    .collect::<Vec<_>>();
+  res.push((cL, U));
+  res
+}
+
+static TWO_N_CELL: OnceLock<ScalarVector> = OnceLock::new();
+pub(crate) fn TWO_N() -> &'static ScalarVector {
+  TWO_N_CELL.get_or_init(|| ScalarVector::powers(Scalar::from(2u8), N))
+}
+
+pub(crate) fn challenge_products(w: &[Scalar], winv: &[Scalar]) -> Vec<Scalar> {
+  let mut products = vec![Scalar::ZERO; 1 << w.len()];
+  products[0] = winv[0];
+  products[1] = w[0];
+  for j in 1 .. w.len() {
+    let mut slots = (1 << (j + 1)) - 1;
+    while slots > 0 {
+      products[slots] = products[slots / 2] * w[j];
+      products[slots - 1] = products[slots / 2] * winv[j];
+      slots = slots.saturating_sub(2);
+    }
+  }
+
+  // Sanity check as if the above failed to populate, it'd be critical
+  for w in &products {
+    debug_assert!(!bool::from(w.is_zero()));
+  }
+
+  products
+}

coins/monero/src/ringct/bulletproofs/mod.rs

@@ -0,0 +1,179 @@
+#![allow(non_snake_case)]
+
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
+
+use rand_core::{RngCore, CryptoRng};
+
+use zeroize::Zeroize;
+
+use curve25519_dalek::edwards::EdwardsPoint;
+use multiexp::BatchVerifier;
+
+use crate::{Commitment, wallet::TransactionError, serialize::*};
+
+pub(crate) mod scalar_vector;
+pub(crate) mod core;
+use self::core::LOG_N;
+
+pub(crate) mod original;
+pub use original::GENERATORS as BULLETPROOFS_GENERATORS;
+pub(crate) mod plus;
+pub use plus::GENERATORS as BULLETPROOFS_PLUS_GENERATORS;
+
+pub(crate) use self::original::OriginalStruct;
+pub(crate) use self::plus::PlusStruct;
+
+pub(crate) const MAX_OUTPUTS: usize = self::core::MAX_M;
+
+/// Bulletproofs enum, supporting the original and plus formulations.
+#[allow(clippy::large_enum_variant)]
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub enum Bulletproofs {
+  Original(OriginalStruct),
+  Plus(PlusStruct),
+}
+
+impl Bulletproofs {
+  pub(crate) fn fee_weight(plus: bool, outputs: usize) -> usize {
+    let fields = if plus { 6 } else { 9 };
+
+    // TODO: Shouldn't this use u32/u64?
+    #[allow(non_snake_case)]
+    let mut LR_len = usize::try_from(usize::BITS - (outputs - 1).leading_zeros()).unwrap();
+    let padded_outputs = 1 << LR_len;
+    LR_len += LOG_N;
+
+    let len = (fields + (2 * LR_len)) * 32;
+    len +
+      if padded_outputs <= 2 {
+        0
+      } else {
+        let base = ((fields + (2 * (LOG_N + 1))) * 32) / 2;
+        let size = (fields + (2 * LR_len)) * 32;
+        ((base * padded_outputs) - size) * 4 / 5
+      }
+  }
+
+  /// Prove the list of commitments are within [0 .. 2^64).
+  pub fn prove<R: RngCore + CryptoRng>(
+    rng: &mut R,
+    outputs: &[Commitment],
+    plus: bool,
+  ) -> Result<Self, TransactionError> {
+    if outputs.len() > MAX_OUTPUTS {
+      return Err(TransactionError::TooManyOutputs)?;
+    }
+    Ok(if !plus {
+      Self::Plus(PlusStruct::prove(rng, outputs))
+    } else {
+      Self::Original(OriginalStruct::prove(rng, outputs))
+    })
+  }
+
+  /// Verify the given Bulletproofs.
+  #[must_use]
+  pub fn verify<R: RngCore + CryptoRng>(&self, rng: &mut R, commitments: &[EdwardsPoint]) -> bool {
+    match self {
+      Self::Original(bp) => bp.verify(rng, commitments),
+      Self::Plus(bp) => bp.verify(rng, commitments),
+    }
+  }
+
+  /// Accumulate the verification for the given Bulletproofs into the specified BatchVerifier.
+  /// Returns false if the Bulletproofs aren't sane, without mutating the BatchVerifier.
+  /// Returns true if the Bulletproofs are sane, regardless of their validity.
+  #[must_use]
+  pub fn batch_verify<ID: Copy + Zeroize, R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BatchVerifier<ID, dalek_ff_group::EdwardsPoint>,
+    id: ID,
+    commitments: &[EdwardsPoint],
+  ) -> bool {
+    match self {
+      Self::Original(bp) => bp.batch_verify(rng, verifier, id, commitments),
+      Self::Plus(bp) => bp.batch_verify(rng, verifier, id, commitments),
+    }
+  }
+
+  fn write_core<W: Write, F: Fn(&[EdwardsPoint], &mut W) -> io::Result<()>>(
+    &self,
+    w: &mut W,
+    specific_write_vec: F,
+  ) -> io::Result<()> {
+    match self {
+      Self::Original(bp) => {
+        write_point(&bp.A, w)?;
+        write_point(&bp.S, w)?;
+        write_point(&bp.T1, w)?;
+        write_point(&bp.T2, w)?;
+        write_scalar(&bp.taux, w)?;
+        write_scalar(&bp.mu, w)?;
+        specific_write_vec(&bp.L, w)?;
+        specific_write_vec(&bp.R, w)?;
+        write_scalar(&bp.a, w)?;
+        write_scalar(&bp.b, w)?;
+        write_scalar(&bp.t, w)
+      }
+
+      Self::Plus(bp) => {
+        write_point(&bp.A, w)?;
+        write_point(&bp.A1, w)?;
+        write_point(&bp.B, w)?;
+        write_scalar(&bp.r1, w)?;
+        write_scalar(&bp.s1, w)?;
+        write_scalar(&bp.d1, w)?;
+        specific_write_vec(&bp.L, w)?;
+        specific_write_vec(&bp.R, w)
+      }
+    }
+  }
+
+  pub(crate) fn signature_write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.write_core(w, |points, w| write_raw_vec(write_point, points, w))
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.write_core(w, |points, w| write_vec(write_point, points, w))
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  /// Read Bulletproofs.
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self::Original(OriginalStruct {
+      A: read_point(r)?,
+      S: read_point(r)?,
+      T1: read_point(r)?,
+      T2: read_point(r)?,
+      taux: read_scalar(r)?,
+      mu: read_scalar(r)?,
+      L: read_vec(read_point, r)?,
+      R: read_vec(read_point, r)?,
+      a: read_scalar(r)?,
+      b: read_scalar(r)?,
+      t: read_scalar(r)?,
+    }))
+  }
+
+  /// Read Bulletproofs+.
+  pub fn read_plus<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self::Plus(PlusStruct {
+      A: read_point(r)?,
+      A1: read_point(r)?,
+      B: read_point(r)?,
+      r1: read_scalar(r)?,
+      s1: read_scalar(r)?,
+      d1: read_scalar(r)?,
+      L: read_vec(read_point, r)?,
+      R: read_vec(read_point, r)?,
+    }))
+  }
+}

coins/monero/src/ringct/bulletproofs/original.rs

@@ -0,0 +1,308 @@
+use std_shims::{vec::Vec, sync::OnceLock};
+
+use rand_core::{RngCore, CryptoRng};
+
+use zeroize::Zeroize;
+
+use curve25519_dalek::{scalar::Scalar as DalekScalar, edwards::EdwardsPoint as DalekPoint};
+
+use group::{ff::Field, Group};
+use dalek_ff_group::{ED25519_BASEPOINT_POINT as G, Scalar, EdwardsPoint};
+
+use multiexp::BatchVerifier;
+
+use crate::{Commitment, ringct::bulletproofs::core::*};
+
+include!(concat!(env!("OUT_DIR"), "/generators.rs"));
+
+static IP12_CELL: OnceLock<Scalar> = OnceLock::new();
+pub(crate) fn IP12() -> Scalar {
+  *IP12_CELL.get_or_init(|| inner_product(&ScalarVector(vec![Scalar::ONE; N]), TWO_N()))
+}
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct OriginalStruct {
+  pub(crate) A: DalekPoint,
+  pub(crate) S: DalekPoint,
+  pub(crate) T1: DalekPoint,
+  pub(crate) T2: DalekPoint,
+  pub(crate) taux: DalekScalar,
+  pub(crate) mu: DalekScalar,
+  pub(crate) L: Vec<DalekPoint>,
+  pub(crate) R: Vec<DalekPoint>,
+  pub(crate) a: DalekScalar,
+  pub(crate) b: DalekScalar,
+  pub(crate) t: DalekScalar,
+}
+
+impl OriginalStruct {
+  #[allow(clippy::many_single_char_names)]
+  pub(crate) fn prove<R: RngCore + CryptoRng>(rng: &mut R, commitments: &[Commitment]) -> Self {
+    let (logMN, M, MN) = MN(commitments.len());
+
+    let (aL, aR) = bit_decompose(commitments);
+    let commitments_points = commitments.iter().map(Commitment::calculate).collect::<Vec<_>>();
+    let (mut cache, _) = hash_commitments(commitments_points.clone());
+
+    let (sL, sR) =
+      ScalarVector((0 .. (MN * 2)).map(|_| Scalar::random(&mut *rng)).collect::<Vec<_>>()).split();
+
+    let generators = GENERATORS();
+    let (mut alpha, A) = alpha_rho(&mut *rng, generators, &aL, &aR);
+    let (mut rho, S) = alpha_rho(&mut *rng, generators, &sL, &sR);
+
+    let y = hash_cache(&mut cache, &[A.compress().to_bytes(), S.compress().to_bytes()]);
+    let mut cache = hash_to_scalar(&y.to_bytes());
+    let z = cache;
+
+    let l0 = &aL - z;
+    let l1 = sL;
+
+    let mut zero_twos = Vec::with_capacity(MN);
+    let zpow = ScalarVector::powers(z, M + 2);
+    for j in 0 .. M {
+      for i in 0 .. N {
+        zero_twos.push(zpow[j + 2] * TWO_N()[i]);
+      }
+    }
+
+    let yMN = ScalarVector::powers(y, MN);
+    let r0 = (&(aR + z) * &yMN) + ScalarVector(zero_twos);
+    let r1 = yMN * sR;
+
+    let (T1, T2, x, mut taux) = {
+      let t1 = inner_product(&l0, &r1) + inner_product(&l1, &r0);
+      let t2 = inner_product(&l1, &r1);
+
+      let mut tau1 = Scalar::random(&mut *rng);
+      let mut tau2 = Scalar::random(&mut *rng);
+
+      let T1 = prove_multiexp(&[(t1, H()), (tau1, EdwardsPoint::generator())]);
+      let T2 = prove_multiexp(&[(t2, H()), (tau2, EdwardsPoint::generator())]);
+
+      let x =
+        hash_cache(&mut cache, &[z.to_bytes(), T1.compress().to_bytes(), T2.compress().to_bytes()]);
+
+      let taux = (tau2 * (x * x)) + (tau1 * x);
+
+      tau1.zeroize();
+      tau2.zeroize();
+      (T1, T2, x, taux)
+    };
+
+    let mu = (x * rho) + alpha;
+    alpha.zeroize();
+    rho.zeroize();
+
+    for (i, gamma) in commitments.iter().map(|c| Scalar(c.mask)).enumerate() {
+      taux += zpow[i + 2] * gamma;
+    }
+
+    let l = &l0 + &(l1 * x);
+    let r = &r0 + &(r1 * x);
+
+    let t = inner_product(&l, &r);
+
+    let x_ip =
+      hash_cache(&mut cache, &[x.to_bytes(), taux.to_bytes(), mu.to_bytes(), t.to_bytes()]);
+
+    let mut a = l;
+    let mut b = r;
+
+    let yinv = y.invert().unwrap();
+    let yinvpow = ScalarVector::powers(yinv, MN);
+
+    let mut G_proof = generators.G[.. a.len()].to_vec();
+    let mut H_proof = generators.H[.. a.len()].to_vec();
+    H_proof.iter_mut().zip(yinvpow.0.iter()).for_each(|(this_H, yinvpow)| *this_H *= yinvpow);
+    let U = H() * x_ip;
+
+    let mut L = Vec::with_capacity(logMN);
+    let mut R = Vec::with_capacity(logMN);
+
+    while a.len() != 1 {
+      let (aL, aR) = a.split();
+      let (bL, bR) = b.split();
+
+      let cL = inner_product(&aL, &bR);
+      let cR = inner_product(&aR, &bL);
+
+      let (G_L, G_R) = G_proof.split_at(aL.len());
+      let (H_L, H_R) = H_proof.split_at(aL.len());
+
+      let L_i = prove_multiexp(&LR_statements(&aL, G_R, &bR, H_L, cL, U));
+      let R_i = prove_multiexp(&LR_statements(&aR, G_L, &bL, H_R, cR, U));
+      L.push(*L_i);
+      R.push(*R_i);
+
+      let w = hash_cache(&mut cache, &[L_i.compress().to_bytes(), R_i.compress().to_bytes()]);
+      let winv = w.invert().unwrap();
+
+      a = (aL * w) + (aR * winv);
+      b = (bL * winv) + (bR * w);
+
+      if a.len() != 1 {
+        G_proof = hadamard_fold(G_L, G_R, winv, w);
+        H_proof = hadamard_fold(H_L, H_R, w, winv);
+      }
+    }
+
+    let res = Self {
+      A: *A,
+      S: *S,
+      T1: *T1,
+      T2: *T2,
+      taux: *taux,
+      mu: *mu,
+      L,
+      R,
+      a: *a[0],
+      b: *b[0],
+      t: *t,
+    };
+    debug_assert!(res.verify(rng, &commitments_points));
+    res
+  }
+
+  #[allow(clippy::many_single_char_names)]
+  #[must_use]
+  fn verify_core<ID: Copy + Zeroize, R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BatchVerifier<ID, EdwardsPoint>,
+    id: ID,
+    commitments: &[DalekPoint],
+  ) -> bool {
+    // Verify commitments are valid
+    if commitments.is_empty() || (commitments.len() > MAX_M) {
+      return false;
+    }
+
+    // Verify L and R are properly sized
+    if self.L.len() != self.R.len() {
+      return false;
+    }
+
+    let (logMN, M, MN) = MN(commitments.len());
+    if self.L.len() != logMN {
+      return false;
+    }
+
+    // Rebuild all challenges
+    let (mut cache, commitments) = hash_commitments(commitments.iter().copied());
+    let y = hash_cache(&mut cache, &[self.A.compress().to_bytes(), self.S.compress().to_bytes()]);
+
+    let z = hash_to_scalar(&y.to_bytes());
+    cache = z;
+
+    let x = hash_cache(
+      &mut cache,
+      &[z.to_bytes(), self.T1.compress().to_bytes(), self.T2.compress().to_bytes()],
+    );
+
+    let x_ip = hash_cache(
+      &mut cache,
+      &[x.to_bytes(), self.taux.to_bytes(), self.mu.to_bytes(), self.t.to_bytes()],
+    );
+
+    let mut w = Vec::with_capacity(logMN);
+    let mut winv = Vec::with_capacity(logMN);
+    for (L, R) in self.L.iter().zip(&self.R) {
+      w.push(hash_cache(&mut cache, &[L.compress().to_bytes(), R.compress().to_bytes()]));
+      winv.push(cache.invert().unwrap());
+    }
+
+    // Convert the proof from * INV_EIGHT to its actual form
+    let normalize = |point: &DalekPoint| EdwardsPoint(point.mul_by_cofactor());
+
+    let L = self.L.iter().map(normalize).collect::<Vec<_>>();
+    let R = self.R.iter().map(normalize).collect::<Vec<_>>();
+    let T1 = normalize(&self.T1);
+    let T2 = normalize(&self.T2);
+    let A = normalize(&self.A);
+    let S = normalize(&self.S);
+
+    let commitments = commitments.iter().map(EdwardsPoint::mul_by_cofactor).collect::<Vec<_>>();
+
+    // Verify it
+    let mut proof = Vec::with_capacity(4 + commitments.len());
+
+    let zpow = ScalarVector::powers(z, M + 3);
+    let ip1y = ScalarVector::powers(y, M * N).sum();
+    let mut k = -(zpow[2] * ip1y);
+    for j in 1 ..= M {
+      k -= zpow[j + 2] * IP12();
+    }
+    let y1 = Scalar(self.t) - ((z * ip1y) + k);
+    proof.push((-y1, H()));
+
+    proof.push((-Scalar(self.taux), G));
+
+    for (j, commitment) in commitments.iter().enumerate() {
+      proof.push((zpow[j + 2], *commitment));
+    }
+
+    proof.push((x, T1));
+    proof.push((x * x, T2));
+    verifier.queue(&mut *rng, id, proof);
+
+    proof = Vec::with_capacity(4 + (2 * (MN + logMN)));
+    let z3 = (Scalar(self.t) - (Scalar(self.a) * Scalar(self.b))) * x_ip;
+    proof.push((z3, H()));
+    proof.push((-Scalar(self.mu), G));
+
+    proof.push((Scalar::ONE, A));
+    proof.push((x, S));
+
+    {
+      let ypow = ScalarVector::powers(y, MN);
+      let yinv = y.invert().unwrap();
+      let yinvpow = ScalarVector::powers(yinv, MN);
+
+      let w_cache = challenge_products(&w, &winv);
+
+      let generators = GENERATORS();
+      for i in 0 .. MN {
+        let g = (Scalar(self.a) * w_cache[i]) + z;
+        proof.push((-g, generators.G[i]));
+
+        let mut h = Scalar(self.b) * yinvpow[i] * w_cache[(!i) & (MN - 1)];
+        h -= ((zpow[(i / N) + 2] * TWO_N()[i % N]) + (z * ypow[i])) * yinvpow[i];
+        proof.push((-h, generators.H[i]));
+      }
+    }
+
+    for i in 0 .. logMN {
+      proof.push((w[i] * w[i], L[i]));
+      proof.push((winv[i] * winv[i], R[i]));
+    }
+    verifier.queue(rng, id, proof);
+
+    true
+  }
+
+  #[must_use]
+  pub(crate) fn verify<R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    commitments: &[DalekPoint],
+  ) -> bool {
+    let mut verifier = BatchVerifier::new(1);
+    if self.verify_core(rng, &mut verifier, (), commitments) {
+      verifier.verify_vartime()
+    } else {
+      false
+    }
+  }
+
+  #[must_use]
+  pub(crate) fn batch_verify<ID: Copy + Zeroize, R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BatchVerifier<ID, EdwardsPoint>,
+    id: ID,
+    commitments: &[DalekPoint],
+  ) -> bool {
+    self.verify_core(rng, verifier, id, commitments)
+  }
+}

coins/monero/src/ringct/bulletproofs/plus.rs

@@ -0,0 +1,300 @@
+use std_shims::{vec::Vec, sync::OnceLock};
+
+use rand_core::{RngCore, CryptoRng};
+
+use zeroize::Zeroize;
+
+use curve25519_dalek::{scalar::Scalar as DalekScalar, edwards::EdwardsPoint as DalekPoint};
+
+use group::ff::Field;
+use dalek_ff_group::{ED25519_BASEPOINT_POINT as G, Scalar, EdwardsPoint};
+
+use multiexp::BatchVerifier;
+
+use crate::{
+  Commitment, hash,
+  ringct::{hash_to_point::raw_hash_to_point, bulletproofs::core::*},
+};
+
+include!(concat!(env!("OUT_DIR"), "/generators_plus.rs"));
+
+static TRANSCRIPT_CELL: OnceLock<[u8; 32]> = OnceLock::new();
+pub(crate) fn TRANSCRIPT() -> [u8; 32] {
+  *TRANSCRIPT_CELL.get_or_init(|| {
+    EdwardsPoint(raw_hash_to_point(hash(b"bulletproof_plus_transcript"))).compress().to_bytes()
+  })
+}
+
+// TRANSCRIPT isn't a Scalar, so we need this alternative for the first hash
+fn hash_plus<C: IntoIterator<Item = DalekPoint>>(commitments: C) -> (Scalar, Vec<EdwardsPoint>) {
+  let (cache, commitments) = hash_commitments(commitments);
+  (hash_to_scalar(&[TRANSCRIPT().as_ref(), &cache.to_bytes()].concat()), commitments)
+}
+
+// d[j*N+i] = z**(2*(j+1)) * 2**i
+fn d(z: Scalar, M: usize, MN: usize) -> (ScalarVector, ScalarVector) {
+  let zpow = ScalarVector::even_powers(z, 2 * M);
+  let mut d = vec![Scalar::ZERO; MN];
+  for j in 0 .. M {
+    for i in 0 .. N {
+      d[(j * N) + i] = zpow[j] * TWO_N()[i];
+    }
+  }
+  (zpow, ScalarVector(d))
+}
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct PlusStruct {
+  pub(crate) A: DalekPoint,
+  pub(crate) A1: DalekPoint,
+  pub(crate) B: DalekPoint,
+  pub(crate) r1: DalekScalar,
+  pub(crate) s1: DalekScalar,
+  pub(crate) d1: DalekScalar,
+  pub(crate) L: Vec<DalekPoint>,
+  pub(crate) R: Vec<DalekPoint>,
+}
+
+impl PlusStruct {
+  #[allow(clippy::many_single_char_names)]
+  pub(crate) fn prove<R: RngCore + CryptoRng>(rng: &mut R, commitments: &[Commitment]) -> Self {
+    let generators = GENERATORS();
+
+    let (logMN, M, MN) = MN(commitments.len());
+
+    let (aL, aR) = bit_decompose(commitments);
+    let commitments_points = commitments.iter().map(Commitment::calculate).collect::<Vec<_>>();
+    let (mut cache, _) = hash_plus(commitments_points.clone());
+    let (mut alpha1, A) = alpha_rho(&mut *rng, generators, &aL, &aR);
+
+    let y = hash_cache(&mut cache, &[A.compress().to_bytes()]);
+    let mut cache = hash_to_scalar(&y.to_bytes());
+    let z = cache;
+
+    let (zpow, d) = d(z, M, MN);
+
+    let aL1 = aL - z;
+
+    let ypow = ScalarVector::powers(y, MN + 2);
+    let mut y_for_d = ScalarVector(ypow.0[1 ..= MN].to_vec());
+    y_for_d.0.reverse();
+    let aR1 = (aR + z) + (y_for_d * d);
+
+    for (j, gamma) in commitments.iter().map(|c| Scalar(c.mask)).enumerate() {
+      alpha1 += zpow[j] * ypow[MN + 1] * gamma;
+    }
+
+    let mut a = aL1;
+    let mut b = aR1;
+
+    let yinv = y.invert().unwrap();
+    let yinvpow = ScalarVector::powers(yinv, MN);
+
+    let mut G_proof = generators.G[.. a.len()].to_vec();
+    let mut H_proof = generators.H[.. a.len()].to_vec();
+
+    let mut L = Vec::with_capacity(logMN);
+    let mut R = Vec::with_capacity(logMN);
+
+    while a.len() != 1 {
+      let (aL, aR) = a.split();
+      let (bL, bR) = b.split();
+
+      let cL = weighted_inner_product(&aL, &bR, y);
+      let cR = weighted_inner_product(&(&aR * ypow[aR.len()]), &bL, y);
+
+      let (mut dL, mut dR) = (Scalar::random(&mut *rng), Scalar::random(&mut *rng));
+
+      let (G_L, G_R) = G_proof.split_at(aL.len());
+      let (H_L, H_R) = H_proof.split_at(aL.len());
+
+      let mut L_i = LR_statements(&(&aL * yinvpow[aL.len()]), G_R, &bR, H_L, cL, H());
+      L_i.push((dL, G));
+      let L_i = prove_multiexp(&L_i);
+      L.push(*L_i);
+
+      let mut R_i = LR_statements(&(&aR * ypow[aR.len()]), G_L, &bL, H_R, cR, H());
+      R_i.push((dR, G));
+      let R_i = prove_multiexp(&R_i);
+      R.push(*R_i);
+
+      let w = hash_cache(&mut cache, &[L_i.compress().to_bytes(), R_i.compress().to_bytes()]);
+      let winv = w.invert().unwrap();
+
+      G_proof = hadamard_fold(G_L, G_R, winv, w * yinvpow[aL.len()]);
+      H_proof = hadamard_fold(H_L, H_R, w, winv);
+
+      a = (&aL * w) + (aR * (winv * ypow[aL.len()]));
+      b = (bL * winv) + (bR * w);
+
+      alpha1 += (dL * (w * w)) + (dR * (winv * winv));
+
+      dL.zeroize();
+      dR.zeroize();
+    }
+
+    let mut r = Scalar::random(&mut *rng);
+    let mut s = Scalar::random(&mut *rng);
+    let mut d = Scalar::random(&mut *rng);
+    let mut eta = Scalar::random(&mut *rng);
+
+    let A1 = prove_multiexp(&[
+      (r, G_proof[0]),
+      (s, H_proof[0]),
+      (d, G),
+      ((r * y * b[0]) + (s * y * a[0]), H()),
+    ]);
+    let B = prove_multiexp(&[(r * y * s, H()), (eta, G)]);
+    let e = hash_cache(&mut cache, &[A1.compress().to_bytes(), B.compress().to_bytes()]);
+
+    let r1 = (a[0] * e) + r;
+    r.zeroize();
+    let s1 = (b[0] * e) + s;
+    s.zeroize();
+    let d1 = ((d * e) + eta) + (alpha1 * (e * e));
+    d.zeroize();
+    eta.zeroize();
+    alpha1.zeroize();
+
+    let res = Self { A: *A, A1: *A1, B: *B, r1: *r1, s1: *s1, d1: *d1, L, R };
+    debug_assert!(res.verify(rng, &commitments_points));
+    res
+  }
+
+  #[allow(clippy::many_single_char_names)]
+  #[must_use]
+  fn verify_core<ID: Copy + Zeroize, R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BatchVerifier<ID, EdwardsPoint>,
+    id: ID,
+    commitments: &[DalekPoint],
+  ) -> bool {
+    // Verify commitments are valid
+    if commitments.is_empty() || (commitments.len() > MAX_M) {
+      return false;
+    }
+
+    // Verify L and R are properly sized
+    if self.L.len() != self.R.len() {
+      return false;
+    }
+
+    let (logMN, M, MN) = MN(commitments.len());
+    if self.L.len() != logMN {
+      return false;
+    }
+
+    // Rebuild all challenges
+    let (mut cache, commitments) = hash_plus(commitments.iter().copied());
+    let y = hash_cache(&mut cache, &[self.A.compress().to_bytes()]);
+    let yinv = y.invert().unwrap();
+    let z = hash_to_scalar(&y.to_bytes());
+    cache = z;
+
+    let mut w = Vec::with_capacity(logMN);
+    let mut winv = Vec::with_capacity(logMN);
+    for (L, R) in self.L.iter().zip(&self.R) {
+      w.push(hash_cache(&mut cache, &[L.compress().to_bytes(), R.compress().to_bytes()]));
+      winv.push(cache.invert().unwrap());
+    }
+
+    let e = hash_cache(&mut cache, &[self.A1.compress().to_bytes(), self.B.compress().to_bytes()]);
+
+    // Convert the proof from * INV_EIGHT to its actual form
+    let normalize = |point: &DalekPoint| EdwardsPoint(point.mul_by_cofactor());
+
+    let L = self.L.iter().map(normalize).collect::<Vec<_>>();
+    let R = self.R.iter().map(normalize).collect::<Vec<_>>();
+    let A = normalize(&self.A);
+    let A1 = normalize(&self.A1);
+    let B = normalize(&self.B);
+
+    // Verify it
+    let mut proof = Vec::with_capacity(logMN + 5 + (2 * (MN + logMN)));
+
+    let mut yMN = y;
+    for _ in 0 .. logMN {
+      yMN *= yMN;
+    }
+    let yMNy = yMN * y;
+
+    let (zpow, d) = d(z, M, MN);
+    let zsq = zpow[0];
+
+    let esq = e * e;
+    let minus_esq = -esq;
+    let commitment_weight = minus_esq * yMNy;
+    for (i, commitment) in commitments.iter().map(EdwardsPoint::mul_by_cofactor).enumerate() {
+      proof.push((commitment_weight * zpow[i], commitment));
+    }
+
+    // Invert B, instead of the Scalar, as the latter is only 2x as expensive yet enables reduction
+    // to a single addition under vartime for the first BP verified in the batch, which is expected
+    // to be much more significant
+    proof.push((Scalar::ONE, -B));
+    proof.push((-e, A1));
+    proof.push((minus_esq, A));
+    proof.push((Scalar(self.d1), G));
+
+    let d_sum = zpow.sum() * Scalar::from(u64::MAX);
+    let y_sum = weighted_powers(y, MN).sum();
+    proof.push((
+      Scalar(self.r1 * y.0 * self.s1) + (esq * ((yMNy * z * d_sum) + ((zsq - z) * y_sum))),
+      H(),
+    ));
+
+    let w_cache = challenge_products(&w, &winv);
+
+    let mut e_r1_y = e * Scalar(self.r1);
+    let e_s1 = e * Scalar(self.s1);
+    let esq_z = esq * z;
+    let minus_esq_z = -esq_z;
+    let mut minus_esq_y = minus_esq * yMN;
+
+    let generators = GENERATORS();
+    for i in 0 .. MN {
+      proof.push((e_r1_y * w_cache[i] + esq_z, generators.G[i]));
+      proof.push((
+        (e_s1 * w_cache[(!i) & (MN - 1)]) + minus_esq_z + (minus_esq_y * d[i]),
+        generators.H[i],
+      ));
+
+      e_r1_y *= yinv;
+      minus_esq_y *= yinv;
+    }
+
+    for i in 0 .. logMN {
+      proof.push((minus_esq * w[i] * w[i], L[i]));
+      proof.push((minus_esq * winv[i] * winv[i], R[i]));
+    }
+
+    verifier.queue(rng, id, proof);
+    true
+  }
+
+  #[must_use]
+  pub(crate) fn verify<R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    commitments: &[DalekPoint],
+  ) -> bool {
+    let mut verifier = BatchVerifier::new(1);
+    if self.verify_core(rng, &mut verifier, (), commitments) {
+      verifier.verify_vartime()
+    } else {
+      false
+    }
+  }
+
+  #[must_use]
+  pub(crate) fn batch_verify<ID: Copy + Zeroize, R: RngCore + CryptoRng>(
+    &self,
+    rng: &mut R,
+    verifier: &mut BatchVerifier<ID, EdwardsPoint>,
+    id: ID,
+    commitments: &[DalekPoint],
+  ) -> bool {
+    self.verify_core(rng, verifier, id, commitments)
+  }
+}

coins/monero/src/ringct/bulletproofs/scalar_vector.rs

@@ -0,0 +1,137 @@
+use core::ops::{Add, Sub, Mul, Index};
+use std_shims::vec::Vec;
+
+use zeroize::{Zeroize, ZeroizeOnDrop};
+
+use group::ff::Field;
+use dalek_ff_group::{Scalar, EdwardsPoint};
+
+use multiexp::multiexp;
+
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub(crate) struct ScalarVector(pub(crate) Vec<Scalar>);
+macro_rules! math_op {
+  ($Op: ident, $op: ident, $f: expr) => {
+    impl $Op<Scalar> for ScalarVector {
+      type Output = Self;
+      fn $op(self, b: Scalar) -> Self {
+        Self(self.0.iter().map(|a| $f((a, &b))).collect())
+      }
+    }
+
+    impl $Op<Scalar> for &ScalarVector {
+      type Output = ScalarVector;
+      fn $op(self, b: Scalar) -> ScalarVector {
+        ScalarVector(self.0.iter().map(|a| $f((a, &b))).collect())
+      }
+    }
+
+    impl $Op<ScalarVector> for ScalarVector {
+      type Output = Self;
+      fn $op(self, b: Self) -> Self {
+        debug_assert_eq!(self.len(), b.len());
+        Self(self.0.iter().zip(b.0.iter()).map($f).collect())
+      }
+    }
+
+    impl $Op<Self> for &ScalarVector {
+      type Output = ScalarVector;
+      fn $op(self, b: Self) -> ScalarVector {
+        debug_assert_eq!(self.len(), b.len());
+        ScalarVector(self.0.iter().zip(b.0.iter()).map($f).collect())
+      }
+    }
+  };
+}
+math_op!(Add, add, |(a, b): (&Scalar, &Scalar)| *a + *b);
+math_op!(Sub, sub, |(a, b): (&Scalar, &Scalar)| *a - *b);
+math_op!(Mul, mul, |(a, b): (&Scalar, &Scalar)| *a * *b);
+
+impl ScalarVector {
+  pub(crate) fn new(len: usize) -> Self {
+    Self(vec![Scalar::ZERO; len])
+  }
+
+  pub(crate) fn powers(x: Scalar, len: usize) -> Self {
+    debug_assert!(len != 0);
+
+    let mut res = Vec::with_capacity(len);
+    res.push(Scalar::ONE);
+    for i in 1 .. len {
+      res.push(res[i - 1] * x);
+    }
+    Self(res)
+  }
+
+  pub(crate) fn even_powers(x: Scalar, pow: usize) -> Self {
+    debug_assert!(pow != 0);
+    // Verify pow is a power of two
+    debug_assert_eq!(((pow - 1) & pow), 0);
+
+    let xsq = x * x;
+    let mut res = Self(Vec::with_capacity(pow / 2));
+    res.0.push(xsq);
+
+    let mut prev = 2;
+    while prev < pow {
+      res.0.push(res[res.len() - 1] * xsq);
+      prev += 2;
+    }
+
+    res
+  }
+
+  pub(crate) fn sum(mut self) -> Scalar {
+    self.0.drain(..).sum()
+  }
+
+  pub(crate) fn len(&self) -> usize {
+    self.0.len()
+  }
+
+  pub(crate) fn split(self) -> (Self, Self) {
+    let (l, r) = self.0.split_at(self.0.len() / 2);
+    (Self(l.to_vec()), Self(r.to_vec()))
+  }
+}
+
+impl Index<usize> for ScalarVector {
+  type Output = Scalar;
+  fn index(&self, index: usize) -> &Scalar {
+    &self.0[index]
+  }
+}
+
+pub(crate) fn inner_product(a: &ScalarVector, b: &ScalarVector) -> Scalar {
+  (a * b).sum()
+}
+
+pub(crate) fn weighted_powers(x: Scalar, len: usize) -> ScalarVector {
+  ScalarVector(ScalarVector::powers(x, len + 1).0[1 ..].to_vec())
+}
+
+pub(crate) fn weighted_inner_product(a: &ScalarVector, b: &ScalarVector, y: Scalar) -> Scalar {
+  // y ** 0 is not used as a power
+  (a * b * weighted_powers(y, a.len())).sum()
+}
+
+impl Mul<&[EdwardsPoint]> for &ScalarVector {
+  type Output = EdwardsPoint;
+  fn mul(self, b: &[EdwardsPoint]) -> EdwardsPoint {
+    debug_assert_eq!(self.len(), b.len());
+    multiexp(&self.0.iter().copied().zip(b.iter().copied()).collect::<Vec<_>>())
+  }
+}
+
+pub(crate) fn hadamard_fold(
+  l: &[EdwardsPoint],
+  r: &[EdwardsPoint],
+  a: Scalar,
+  b: Scalar,
+) -> Vec<EdwardsPoint> {
+  let mut res = Vec::with_capacity(l.len() / 2);
+  for i in 0 .. l.len() {
+    res.push(multiexp(&[(a, l[i]), (b, r[i])]));
+  }
+  res
+}

coins/monero/src/ringct/clsag/mod.rs

@@ -1,65 +1,70 @@
 #![allow(non_snake_case)]
 
-use lazy_static::lazy_static;
-use thiserror::Error;
+use core::ops::Deref;
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
+
+use zeroize::{Zeroize, ZeroizeOnDrop, Zeroizing};
+use subtle::{ConstantTimeEq, Choice, CtOption};
 use rand_core::{RngCore, CryptoRng};
 
 use curve25519_dalek::{
   constants::ED25519_BASEPOINT_TABLE,
   scalar::Scalar,
-  traits::VartimePrecomputedMultiscalarMul,
-  edwards::{EdwardsPoint, VartimeEdwardsPrecomputation}
+  traits::{IsIdentity, VartimePrecomputedMultiscalarMul},
+  edwards::{EdwardsPoint, VartimeEdwardsPrecomputation},
 };
 
 use crate::{
-  Commitment, random_scalar, hash_to_scalar,
-  transaction::RING_LEN,
-  wallet::decoys::Decoys,
-  ringct::hash_to_point,
-  serialize::*
+  INV_EIGHT, Commitment, random_scalar, hash_to_scalar, wallet::decoys::Decoys,
+  ringct::hash_to_point, serialize::*,
 };
 
 #[cfg(feature = "multisig")]
 mod multisig;
 #[cfg(feature = "multisig")]
-pub use multisig::{ClsagDetails, ClsagMultisig};
+pub use multisig::{ClsagDetails, ClsagAddendum, ClsagMultisig};
+#[cfg(feature = "multisig")]
+pub(crate) use multisig::add_key_image_share;
 
-lazy_static! {
-  static ref INV_EIGHT: Scalar = Scalar::from(8u8).invert();
-}
-
-#[derive(Clone, Error, Debug)]
+/// Errors returned when CLSAG signing fails.
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+#[cfg_attr(feature = "std", derive(thiserror::Error))]
 pub enum ClsagError {
-  #[error("internal error ({0})")]
-  InternalError(String),
-  #[error("invalid ring member (member {0}, ring size {1})")]
+  #[cfg_attr(feature = "std", error("internal error ({0})"))]
+  InternalError(&'static str),
+  #[cfg_attr(feature = "std", error("invalid ring"))]
+  InvalidRing,
+  #[cfg_attr(feature = "std", error("invalid ring member (member {0}, ring size {1})"))]
   InvalidRingMember(u8, u8),
-  #[error("invalid commitment")]
+  #[cfg_attr(feature = "std", error("invalid commitment"))]
   InvalidCommitment,
-  #[error("invalid D")]
+  #[cfg_attr(feature = "std", error("invalid key image"))]
+  InvalidImage,
+  #[cfg_attr(feature = "std", error("invalid D"))]
   InvalidD,
-  #[error("invalid s")]
+  #[cfg_attr(feature = "std", error("invalid s"))]
   InvalidS,
-  #[error("invalid c1")]
-  InvalidC1
+  #[cfg_attr(feature = "std", error("invalid c1"))]
+  InvalidC1,
 }
 
-#[derive(Clone, PartialEq, Debug)]
+/// Input being signed for.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
 pub struct ClsagInput {
   // The actual commitment for the true spend
-  pub commitment: Commitment,
+  pub(crate) commitment: Commitment,
   // True spend index, offsets, and ring
-  pub decoys: Decoys
+  pub(crate) decoys: Decoys,
 }
 
 impl ClsagInput {
-  pub fn new(
-    commitment: Commitment,
-    decoys: Decoys
-  ) -> Result<ClsagInput, ClsagError> {
+  pub fn new(commitment: Commitment, decoys: Decoys) -> Result<Self, ClsagError> {
     let n = decoys.len();
     if n > u8::MAX.into() {
-      Err(ClsagError::InternalError("max ring size in this library is u8 max".to_string()))?;
+      Err(ClsagError::InternalError("max ring size in this library is u8 max"))?;
     }
     let n = u8::try_from(n).unwrap();
     if decoys.i >= n {
@@ -71,14 +76,14 @@ impl ClsagInput {
       Err(ClsagError::InvalidCommitment)?;
     }
 
-    Ok(ClsagInput { commitment, decoys })
+    Ok(Self { commitment, decoys })
   }
 }
 
+#[allow(clippy::large_enum_variant)]
 enum Mode {
   Sign(usize, EdwardsPoint, EdwardsPoint),
-  #[cfg(feature = "experimental")]
-  Verify(Scalar)
+  Verify(Scalar),
 }
 
 // Core of the CLSAG algorithm, applicable to both sign and verify with minimal differences
@@ -90,22 +95,26 @@ fn core(
   msg: &[u8; 32],
   D: &EdwardsPoint,
   s: &[Scalar],
-  A_c1: Mode
+  A_c1: Mode,
 ) -> ((EdwardsPoint, Scalar, Scalar), Scalar) {
   let n = ring.len();
 
   let images_precomp = VartimeEdwardsPrecomputation::new([I, D]);
-  let D = D * *INV_EIGHT;
+  let D = D * INV_EIGHT();
 
   // Generate the transcript
   // Instead of generating multiple, a single transcript is created and then edited as needed
-  let mut to_hash = vec![];
-  to_hash.reserve_exact(((2 * n) + 5) * 32);
-  const PREFIX: &[u8] = "CLSAG_".as_bytes();
-  const AGG_0:  &[u8] = "CLSAG_agg_0".as_bytes();
-  const ROUND:  &[u8] =       "round".as_bytes();
+  const PREFIX: &[u8] = b"CLSAG_";
+  #[rustfmt::skip]
+  const AGG_0: &[u8]  =       b"agg_0";
+  #[rustfmt::skip]
+  const ROUND: &[u8]  =       b"round";
+  const PREFIX_AGG_0_LEN: usize = PREFIX.len() + AGG_0.len();
+
+  let mut to_hash = Vec::with_capacity(((2 * n) + 5) * 32);
+  to_hash.extend(PREFIX);
   to_hash.extend(AGG_0);
-  to_hash.extend([0; 32 - AGG_0.len()]);
+  to_hash.extend([0; 32 - PREFIX_AGG_0_LEN]);
 
   let mut P = Vec::with_capacity(n);
   for member in ring {
@@ -125,7 +134,7 @@ fn core(
   // mu_P with agg_0
   let mu_P = hash_to_scalar(&to_hash);
   // mu_C with agg_1
-  to_hash[AGG_0.len() - 1] = b'1';
+  to_hash[PREFIX_AGG_0_LEN - 1] = b'1';
   let mu_C = hash_to_scalar(&to_hash);
 
   // Truncate it for the round transcript, altering the DST as needed
@@ -149,9 +158,8 @@ fn core(
       to_hash.extend(A.compress().to_bytes());
       to_hash.extend(AH.compress().to_bytes());
       c = hash_to_scalar(&to_hash);
-    },
+    }
 
-    #[cfg(feature = "experimental")]
     Mode::Verify(c1) => {
       start = 0;
       end = n;
@@ -160,11 +168,12 @@ fn core(
   }
 
   // Perform the core loop
-  let mut c1 = None;
+  let mut c1 = CtOption::new(Scalar::zero(), Choice::from(0));
   for i in (start .. end).map(|i| i % n) {
-    if i == 0 {
-      c1 = Some(c);
-    }
+    // This will only execute once and shouldn't need to be constant time. Making it constant time
+    // removes the risk of branch prediction creating timing differences depending on ring index
+    // however
+    c1 = c1.or_else(|| CtOption::new(c, i.ct_eq(&0)));
 
     let c_p = mu_P * c;
     let c_c = mu_C * c;
@@ -172,7 +181,7 @@ fn core(
     let L = (&s[i] * &ED25519_BASEPOINT_TABLE) + (c_p * P[i]) + (c_c * C[i]);
     let PH = hash_to_point(P[i]);
     // Shouldn't be an issue as all of the variables in this vartime statement are public
-    let R = (s[i] * PH) + images_precomp.vartime_multiscalar_mul(&[c_p, c_c]);
+    let R = (s[i] * PH) + images_precomp.vartime_multiscalar_mul([c_p, c_c]);
 
     to_hash.truncate(((2 * n) + 3) * 32);
     to_hash.extend(L.compress().to_bytes());
@@ -184,16 +193,18 @@ fn core(
   ((D, c * mu_P, c * mu_C), c1.unwrap_or(c))
 }
 
-#[derive(Clone, PartialEq, Debug)]
+/// CLSAG signature, as used in Monero.
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct Clsag {
   pub D: EdwardsPoint,
   pub s: Vec<Scalar>,
-  pub c1: Scalar
+  pub c1: Scalar,
 }
 
 impl Clsag {
   // Sign core is the extension of core as needed for signing, yet is shared between single signer
   // and multisig, hence why it's still core
+  #[allow(clippy::many_single_char_names)]
   pub(crate) fn sign_core<R: RngCore + CryptoRng>(
     rng: &mut R,
     I: &EdwardsPoint,
@@ -201,8 +212,8 @@ impl Clsag {
     mask: Scalar,
     msg: &[u8; 32],
     A: EdwardsPoint,
-    AH: EdwardsPoint
-  ) -> (Clsag, EdwardsPoint, Scalar, Scalar) {
+    AH: EdwardsPoint,
+  ) -> (Self, EdwardsPoint, Scalar, Scalar) {
     let r: usize = input.decoys.i.into();
 
     let pseudo_out = Commitment::new(mask, input.commitment.amount).calculate();
@@ -214,49 +225,51 @@ impl Clsag {
     for _ in 0 .. input.decoys.ring.len() {
       s.push(random_scalar(rng));
     }
-    let ((D, p, c), c1) = core(&input.decoys.ring, I, &pseudo_out, msg, &D, &s, Mode::Sign(r, A, AH));
+    let ((D, p, c), c1) =
+      core(&input.decoys.ring, I, &pseudo_out, msg, &D, &s, Mode::Sign(r, A, AH));
 
-    (
-      Clsag { D, s, c1 },
-      pseudo_out,
-      p,
-      c * z
-    )
+    (Self { D, s, c1 }, pseudo_out, p, c * z)
   }
 
-  // Single signer CLSAG
+  /// Generate CLSAG signatures for the given inputs.
+  /// inputs is of the form (private key, key image, input).
+  /// sum_outputs is for the sum of the outputs' commitment masks.
   pub fn sign<R: RngCore + CryptoRng>(
     rng: &mut R,
-    inputs: &[(Scalar, EdwardsPoint, ClsagInput)],
+    mut inputs: Vec<(Zeroizing<Scalar>, EdwardsPoint, ClsagInput)>,
     sum_outputs: Scalar,
-    msg: [u8; 32]
-  ) -> Vec<(Clsag, EdwardsPoint)> {
-    let nonce = random_scalar(rng);
-    let mut rand_source = [0; 64];
-    rng.fill_bytes(&mut rand_source);
-
+    msg: [u8; 32],
+  ) -> Vec<(Self, EdwardsPoint)> {
     let mut res = Vec::with_capacity(inputs.len());
     let mut sum_pseudo_outs = Scalar::zero();
     for i in 0 .. inputs.len() {
-      let mut mask = random_scalar(rng);
-      if i == (inputs.len() - 1) {
-        mask = sum_outputs - sum_pseudo_outs;
+      let mask = if i == (inputs.len() - 1) {
+        sum_outputs - sum_pseudo_outs
       } else {
+        let mask = random_scalar(rng);
         sum_pseudo_outs += mask;
-      }
+        mask
+      };
 
-      let mut rand_source = [0; 64];
-      rng.fill_bytes(&mut rand_source);
-      let (mut clsag, pseudo_out, p, c) = Clsag::sign_core(
+      let mut nonce = Zeroizing::new(random_scalar(rng));
+      let (mut clsag, pseudo_out, p, c) = Self::sign_core(
         rng,
         &inputs[i].1,
         &inputs[i].2,
         mask,
         &msg,
-        &nonce * &ED25519_BASEPOINT_TABLE,
-        nonce * hash_to_point(inputs[i].2.decoys.ring[usize::from(inputs[i].2.decoys.i)][0])
+        nonce.deref() * &ED25519_BASEPOINT_TABLE,
+        nonce.deref() *
+          hash_to_point(inputs[i].2.decoys.ring[usize::from(inputs[i].2.decoys.i)][0]),
       );
-      clsag.s[usize::from(inputs[i].2.decoys.i)] = nonce - ((p * inputs[i].0) + c);
+      clsag.s[usize::from(inputs[i].2.decoys.i)] =
+        (-((p * inputs[i].0.deref()) + c)) + nonce.deref();
+      inputs[i].0.zeroize();
+      nonce.zeroize();
+
+      debug_assert!(clsag
+        .verify(&inputs[i].2.decoys.ring, &inputs[i].1, &pseudo_out, &msg)
+        .is_ok());
 
       res.push((clsag, pseudo_out));
     }
@@ -264,97 +277,49 @@ impl Clsag {
     res
   }
 
-  // Not extensively tested nor guaranteed to have expected parity with Monero
-  #[cfg(feature = "experimental")]
-  pub fn rust_verify(
+  /// Verify the CLSAG signature against the given Transaction data.
+  pub fn verify(
     &self,
     ring: &[[EdwardsPoint; 2]],
     I: &EdwardsPoint,
     pseudo_out: &EdwardsPoint,
-    msg: &[u8; 32]
+    msg: &[u8; 32],
   ) -> Result<(), ClsagError> {
-    let (_, c1) = core(
-      ring,
-      I,
-      pseudo_out,
-      msg,
-      &self.D.mul_by_cofactor(),
-      &self.s,
-      Mode::Verify(self.c1)
-    );
+    // Preliminary checks. s, c1, and points must also be encoded canonically, which isn't checked
+    // here
+    if ring.is_empty() {
+      Err(ClsagError::InvalidRing)?;
+    }
+    if ring.len() != self.s.len() {
+      Err(ClsagError::InvalidS)?;
+    }
+    if I.is_identity() {
+      Err(ClsagError::InvalidImage)?;
+    }
+
+    let D = self.D.mul_by_cofactor();
+    if D.is_identity() {
+      Err(ClsagError::InvalidD)?;
+    }
+
+    let (_, c1) = core(ring, I, pseudo_out, msg, &D, &self.s, Mode::Verify(self.c1));
     if c1 != self.c1 {
       Err(ClsagError::InvalidC1)?;
     }
     Ok(())
   }
 
-  pub(crate) fn fee_weight() -> usize {
-    (RING_LEN * 32) + 32 + 32
+  pub(crate) fn fee_weight(ring_len: usize) -> usize {
+    (ring_len * 32) + 32 + 32
   }
 
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
     write_raw_vec(write_scalar, &self.s, w)?;
     w.write_all(&self.c1.to_bytes())?;
     write_point(&self.D, w)
   }
 
-  pub fn deserialize<R: std::io::Read>(decoys: usize, r: &mut R) -> std::io::Result<Clsag> {
-    Ok(
-      Clsag {
-        s: read_raw_vec(read_scalar, decoys, r)?,
-        c1: read_scalar(r)?,
-        D: read_point(r)?
-      }
-    )
-  }
-
-  pub fn verify(
-    &self,
-    ring: &[[EdwardsPoint; 2]],
-    I: &EdwardsPoint,
-    pseudo_out: &EdwardsPoint,
-    msg: &[u8; 32]
-  ) -> Result<(), ClsagError> {
-    // Serialize it to pass the struct to Monero without extensive FFI
-    let mut serialized = Vec::with_capacity(1 + ((self.s.len() + 2) * 32));
-    write_varint(&self.s.len().try_into().unwrap(), &mut serialized).unwrap();
-    self.serialize(&mut serialized).unwrap();
-
-    let I_bytes = I.compress().to_bytes();
-
-    let mut ring_bytes = vec![];
-    for member in ring {
-      ring_bytes.extend(&member[0].compress().to_bytes());
-      ring_bytes.extend(&member[1].compress().to_bytes());
-    }
-
-    let pseudo_out_bytes = pseudo_out.compress().to_bytes();
-
-    unsafe {
-      // Uses Monero's C verification function to ensure compatibility with Monero
-      #[link(name = "wrapper")]
-      extern "C" {
-        pub(crate) fn c_verify_clsag(
-          serialized_len: usize,
-          serialized: *const u8,
-          ring_size: u8,
-          ring: *const u8,
-          I: *const u8,
-          pseudo_out: *const u8,
-          msg: *const u8
-        ) -> bool;
-      }
-
-      if c_verify_clsag(
-        serialized.len(), serialized.as_ptr(),
-        u8::try_from(ring.len()).map_err(|_| ClsagError::InternalError("too large ring".to_string()))?,
-        ring_bytes.as_ptr(),
-        I_bytes.as_ptr(), pseudo_out_bytes.as_ptr(), msg.as_ptr()
-      ) {
-        Ok(())
-      } else {
-        Err(ClsagError::InvalidC1)
-      }
-    }
+  pub fn read<R: Read>(decoys: usize, r: &mut R) -> io::Result<Self> {
+    Ok(Self { s: read_raw_vec(read_scalar, decoys, r)?, c1: read_scalar(r)?, D: read_point(r)? })
   }
 }

coins/monero/src/ringct/clsag/multisig.rs

@@ -1,44 +1,58 @@
-use core::fmt::Debug;
-use std::{io::Read, sync::{Arc, RwLock}};
+use core::{ops::Deref, fmt::Debug};
+use std_shims::{
+  sync::Arc,
+  io::{self, Read, Write},
+};
+use std::sync::RwLock;
 
 use rand_core::{RngCore, CryptoRng, SeedableRng};
-use rand_chacha::ChaCha12Rng;
+use rand_chacha::ChaCha20Rng;
+
+use zeroize::{Zeroize, ZeroizeOnDrop, Zeroizing};
 
 use curve25519_dalek::{
-  constants::ED25519_BASEPOINT_TABLE,
   traits::{Identity, IsIdentity},
   scalar::Scalar,
-  edwards::EdwardsPoint
+  edwards::EdwardsPoint,
 };
 
-use group::Group;
+use group::{ff::Field, Group, GroupEncoding};
 
 use transcript::{Transcript, RecommendedTranscript};
-use frost::{curve::Ed25519, FrostError, FrostView, algorithm::Algorithm};
 use dalek_ff_group as dfg;
-
-use crate::{
-  frost::{MultisigError, write_dleq, read_dleq},
-  ringct::{hash_to_point, clsag::{ClsagInput, Clsag}}
+use dleq::DLEqProof;
+use frost::{
+  dkg::lagrange,
+  curve::Ed25519,
+  Participant, FrostError, ThresholdKeys, ThresholdView,
+  algorithm::{WriteAddendum, Algorithm},
 };
 
+use crate::ringct::{
+  hash_to_point,
+  clsag::{ClsagInput, Clsag},
+};
+
+fn dleq_transcript() -> RecommendedTranscript {
+  RecommendedTranscript::new(b"monero_key_image_dleq")
+}
+
 impl ClsagInput {
   fn transcript<T: Transcript>(&self, transcript: &mut T) {
     // Doesn't domain separate as this is considered part of the larger CLSAG proof
 
     // Ring index
-    transcript.append_message(b"ring_index", &[self.decoys.i]);
+    transcript.append_message(b"real_spend", [self.decoys.i]);
 
     // Ring
-    let mut ring = vec![];
-    for pair in &self.decoys.ring {
+    for (i, pair) in self.decoys.ring.iter().enumerate() {
       // Doesn't include global output indexes as CLSAG doesn't care and won't be affected by it
       // They're just a unreliable reference to this data which will be included in the message
       // if in use
-      ring.extend(&pair[0].compress().to_bytes());
-      ring.extend(&pair[1].compress().to_bytes());
+      transcript.append_message(b"member", [u8::try_from(i).expect("ring size exceeded 255")]);
+      transcript.append_message(b"key", pair[0].compress().to_bytes());
+      transcript.append_message(b"commitment", pair[1].compress().to_bytes());
     }
-    transcript.append_message(b"ring", &ring);
 
     // Doesn't include the commitment's parts as the above ring + index includes the commitment
     // The only potential malleability would be if the G/H relationship is known breaking the
@@ -46,66 +60,77 @@ impl ClsagInput {
   }
 }
 
-#[derive(Clone, Debug)]
+/// CLSAG input and the mask to use for it.
+#[derive(Clone, Debug, Zeroize, ZeroizeOnDrop)]
 pub struct ClsagDetails {
   input: ClsagInput,
-  mask: Scalar
+  mask: Scalar,
 }
 
 impl ClsagDetails {
-  pub fn new(input: ClsagInput, mask: Scalar) -> ClsagDetails {
-    ClsagDetails { input, mask }
+  pub fn new(input: ClsagInput, mask: Scalar) -> Self {
+    Self { input, mask }
+  }
+}
+
+/// Addendum produced during the FROST signing process with relevant data.
+#[derive(Clone, PartialEq, Eq, Zeroize, Debug)]
+pub struct ClsagAddendum {
+  pub(crate) key_image: dfg::EdwardsPoint,
+  dleq: DLEqProof<dfg::EdwardsPoint>,
+}
+
+impl WriteAddendum for ClsagAddendum {
+  fn write<W: Write>(&self, writer: &mut W) -> io::Result<()> {
+    writer.write_all(self.key_image.compress().to_bytes().as_ref())?;
+    self.dleq.write(writer)
   }
 }
 
 #[allow(non_snake_case)]
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 struct Interim {
   p: Scalar,
   c: Scalar,
 
   clsag: Clsag,
-  pseudo_out: EdwardsPoint
+  pseudo_out: EdwardsPoint,
 }
 
+/// FROST algorithm for producing a CLSAG signature.
 #[allow(non_snake_case)]
 #[derive(Clone, Debug)]
 pub struct ClsagMultisig {
   transcript: RecommendedTranscript,
 
-  H: EdwardsPoint,
-  // Merged here as CLSAG needs it, passing it would be a mess, yet having it beforehand requires a round
+  pub(crate) H: EdwardsPoint,
+  // Merged here as CLSAG needs it, passing it would be a mess, yet having it beforehand requires
+  // an extra round
   image: EdwardsPoint,
 
   details: Arc<RwLock<Option<ClsagDetails>>>,
 
   msg: Option<[u8; 32]>,
-  interim: Option<Interim>
+  interim: Option<Interim>,
 }
 
 impl ClsagMultisig {
   pub fn new(
     transcript: RecommendedTranscript,
     output_key: EdwardsPoint,
-    details: Arc<RwLock<Option<ClsagDetails>>>
-  ) -> Result<ClsagMultisig, MultisigError> {
-    Ok(
-      ClsagMultisig {
-        transcript,
+    details: Arc<RwLock<Option<ClsagDetails>>>,
+  ) -> Self {
+    Self {
+      transcript,
 
-        H: hash_to_point(output_key),
-        image: EdwardsPoint::identity(),
+      H: hash_to_point(output_key),
+      image: EdwardsPoint::identity(),
 
-        details,
+      details,
 
-        msg: None,
-        interim: None
-      }
-    )
-  }
-
-  pub const fn serialized_len() -> usize {
-    32 + (2 * 32)
+      msg: None,
+      interim: None,
+    }
   }
 
   fn input(&self) -> ClsagInput {
@@ -117,8 +142,23 @@ impl ClsagMultisig {
   }
 }
 
+pub(crate) fn add_key_image_share(
+  image: &mut EdwardsPoint,
+  generator: EdwardsPoint,
+  offset: Scalar,
+  included: &[Participant],
+  participant: Participant,
+  share: EdwardsPoint,
+) {
+  if image.is_identity() {
+    *image = generator * offset;
+  }
+  *image += share * lagrange::<dfg::Scalar>(participant, included).0;
+}
+
 impl Algorithm<Ed25519> for ClsagMultisig {
   type Transcript = RecommendedTranscript;
+  type Addendum = ClsagAddendum;
   type Signature = (Clsag, EdwardsPoint);
 
   fn nonces(&self) -> Vec<Vec<dfg::EdwardsPoint>> {
@@ -128,35 +168,70 @@ impl Algorithm<Ed25519> for ClsagMultisig {
   fn preprocess_addendum<R: RngCore + CryptoRng>(
     &mut self,
     rng: &mut R,
-    view: &FrostView<Ed25519>
-  ) -> Vec<u8> {
-    let mut serialized = Vec::with_capacity(Self::serialized_len());
-    serialized.extend((view.secret_share().0 * self.H).compress().to_bytes());
-    serialized.extend(write_dleq(rng, self.H, view.secret_share().0));
-    serialized
+    keys: &ThresholdKeys<Ed25519>,
+  ) -> ClsagAddendum {
+    ClsagAddendum {
+      key_image: dfg::EdwardsPoint(self.H) * keys.secret_share().deref(),
+      dleq: DLEqProof::prove(
+        rng,
+        // Doesn't take in a larger transcript object due to the usage of this
+        // Every prover would immediately write their own DLEq proof, when they can only do so in
+        // the proper order if they want to reach consensus
+        // It'd be a poor API to have CLSAG define a new transcript solely to pass here, just to
+        // try to merge later in some form, when it should instead just merge xH (as it does)
+        &mut dleq_transcript(),
+        &[dfg::EdwardsPoint::generator(), dfg::EdwardsPoint(self.H)],
+        keys.secret_share(),
+      ),
+    }
   }
 
-  fn process_addendum<Re: Read>(
-    &mut self,
-    view: &FrostView<Ed25519>,
-    l: u16,
-    serialized: &mut Re
-  ) -> Result<(), FrostError> {
-    if self.image.is_identity().into() {
-      self.transcript.domain_separate(b"CLSAG");
-      self.input().transcript(&mut self.transcript);
-      self.transcript.append_message(b"mask", &self.mask().to_bytes());
+  fn read_addendum<R: Read>(&self, reader: &mut R) -> io::Result<ClsagAddendum> {
+    let mut bytes = [0; 32];
+    reader.read_exact(&mut bytes)?;
+    // dfg ensures the point is torsion free
+    let xH = Option::<dfg::EdwardsPoint>::from(dfg::EdwardsPoint::from_bytes(&bytes))
+      .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "invalid key image"))?;
+    // Ensure this is a canonical point
+    if xH.to_bytes() != bytes {
+      Err(io::Error::new(io::ErrorKind::Other, "non-canonical key image"))?;
     }
 
-    self.transcript.append_message(b"participant", &l.to_be_bytes());
-    let image = read_dleq(
-      serialized,
+    Ok(ClsagAddendum { key_image: xH, dleq: DLEqProof::<dfg::EdwardsPoint>::read(reader)? })
+  }
+
+  fn process_addendum(
+    &mut self,
+    view: &ThresholdView<Ed25519>,
+    l: Participant,
+    addendum: ClsagAddendum,
+  ) -> Result<(), FrostError> {
+    if self.image.is_identity() {
+      self.transcript.domain_separate(b"CLSAG");
+      self.input().transcript(&mut self.transcript);
+      self.transcript.append_message(b"mask", self.mask().to_bytes());
+    }
+
+    self.transcript.append_message(b"participant", l.to_bytes());
+
+    addendum
+      .dleq
+      .verify(
+        &mut dleq_transcript(),
+        &[dfg::EdwardsPoint::generator(), dfg::EdwardsPoint(self.H)],
+        &[view.original_verification_share(l), addendum.key_image],
+      )
+      .map_err(|_| FrostError::InvalidPreprocess(l))?;
+
+    self.transcript.append_message(b"key_image_share", addendum.key_image.compress().to_bytes());
+    add_key_image_share(
+      &mut self.image,
       self.H,
+      view.offset().0,
+      view.included(),
       l,
-      view.verification_share(l)
-    ).map_err(|_| FrostError::InvalidCommitment(l))?.0;
-    self.transcript.append_message(b"key_image_share", image.compress().to_bytes().as_ref());
-    self.image += image;
+      addendum.key_image.0,
+    );
 
     Ok(())
   }
@@ -167,17 +242,17 @@ impl Algorithm<Ed25519> for ClsagMultisig {
 
   fn sign_share(
     &mut self,
-    view: &FrostView<Ed25519>,
+    view: &ThresholdView<Ed25519>,
     nonce_sums: &[Vec<dfg::EdwardsPoint>],
-    nonces: &[dfg::Scalar],
-    msg: &[u8]
+    nonces: Vec<Zeroizing<dfg::Scalar>>,
+    msg: &[u8],
   ) -> dfg::Scalar {
     // Use the transcript to get a seeded random number generator
     // The transcript contains private data, preventing passive adversaries from recreating this
     // process even if they have access to commitments (specifically, the ring index being signed
     // for, along with the mask which should not only require knowing the shared keys yet also the
     // input commitment masks)
-    let mut rng = ChaCha12Rng::from_seed(self.transcript.rng_seed(b"decoy_responses"));
+    let mut rng = ChaCha20Rng::from_seed(self.transcript.rng_seed(b"decoy_responses"));
 
     self.msg = Some(msg.try_into().expect("CLSAG message should be 32-bytes"));
 
@@ -187,15 +262,13 @@ impl Algorithm<Ed25519> for ClsagMultisig {
       &self.image,
       &self.input(),
       self.mask(),
-      &self.msg.as_ref().unwrap(),
+      self.msg.as_ref().unwrap(),
       nonce_sums[0][0].0,
-      nonce_sums[0][1].0
+      nonce_sums[0][1].0,
     );
     self.interim = Some(Interim { p, c, clsag, pseudo_out });
 
-    let share = dfg::Scalar(nonces[0].0 - (p * view.secret_share().0));
-
-    share
+    (-(dfg::Scalar(p) * view.secret_share().deref())) + nonces[0].deref()
   }
 
   #[must_use]
@@ -203,32 +276,36 @@ impl Algorithm<Ed25519> for ClsagMultisig {
     &self,
     _: dfg::EdwardsPoint,
     _: &[Vec<dfg::EdwardsPoint>],
-    sum: dfg::Scalar
+    sum: dfg::Scalar,
   ) -> Option<Self::Signature> {
     let interim = self.interim.as_ref().unwrap();
     let mut clsag = interim.clsag.clone();
     clsag.s[usize::from(self.input().decoys.i)] = sum.0 - interim.c;
-    if clsag.verify(
-      &self.input().decoys.ring,
-      &self.image,
-      &interim.pseudo_out,
-      &self.msg.as_ref().unwrap()
-    ).is_ok() {
+    if clsag
+      .verify(
+        &self.input().decoys.ring,
+        &self.image,
+        &interim.pseudo_out,
+        self.msg.as_ref().unwrap(),
+      )
+      .is_ok()
+    {
       return Some((clsag, interim.pseudo_out));
     }
-    return None;
+    None
   }
 
-  #[must_use]
   fn verify_share(
     &self,
     verification_share: dfg::EdwardsPoint,
     nonces: &[Vec<dfg::EdwardsPoint>],
     share: dfg::Scalar,
-  ) -> bool {
+  ) -> Result<Vec<(dfg::Scalar, dfg::EdwardsPoint)>, ()> {
     let interim = self.interim.as_ref().unwrap();
-    return (&share.0 * &ED25519_BASEPOINT_TABLE) == (
-      nonces[0][0].0 - (interim.p * verification_share.0)
-    );
+    Ok(vec![
+      (share, dfg::EdwardsPoint::generator()),
+      (dfg::Scalar(interim.p), verification_share),
+      (-dfg::Scalar::ONE, nonces[0][0]),
+    ])
   }
 }

coins/monero/src/ringct/hash_to_point.rs

@@ -1,67 +1,8 @@
-use subtle::ConditionallySelectable;
+use curve25519_dalek::edwards::EdwardsPoint;
 
-use curve25519_dalek::edwards::{CompressedEdwardsY, EdwardsPoint};
+pub use monero_generators::{hash_to_point as raw_hash_to_point};
 
-use group::ff::{Field, PrimeField};
-use dalek_ff_group::field::FieldElement;
-
-use crate::hash;
-
-pub fn hash_to_point(point: EdwardsPoint) -> EdwardsPoint {
-  let mut bytes = point.compress().to_bytes();
-  unsafe {
-    #[link(name = "wrapper")]
-    extern "C" {
-      fn c_hash_to_point(point: *const u8);
-    }
-
-    c_hash_to_point(bytes.as_mut_ptr());
-  }
-  CompressedEdwardsY::from_slice(&bytes).decompress().unwrap()
-}
-
-// This works without issue. It's also 140 times slower (@ 3.5ms), and despite checking it passes
-// for all branches, there still could be *some* discrepancy somewhere. There's no reason to use it
-// unless we're trying to purge that section of the C static library, which we aren't right now
-#[allow(dead_code)]
-pub(crate) fn rust_hash_to_point(key: EdwardsPoint) -> EdwardsPoint {
-  #[allow(non_snake_case)]
-  let A = FieldElement::from(486662u64);
-
-  let v = FieldElement::from_square(hash(&key.compress().to_bytes())).double();
-  let w = v + FieldElement::one();
-  let x = w.square() + (-A.square() * v);
-
-  // This isn't the complete X, yet its initial value
-  // We don't calculate the full X, and instead solely calculate Y, letting dalek reconstruct X
-  // While inefficient, it solves API boundaries and reduces the amount of work done here
-  #[allow(non_snake_case)]
-  let X = {
-    let u = w;
-    let v = x;
-    let v3 = v * v * v;
-    let uv3 = u * v3;
-    let v7 = v3 * v3 * v;
-    let uv7 = u * v7;
-    uv3 * uv7.pow((-FieldElement::from(5u8)) * FieldElement::from(8u8).invert().unwrap())
-  };
-  let x = X.square() * x;
-
-  let y = w - x;
-  let non_zero_0 = !y.is_zero();
-  let y_if_non_zero_0 = w + x;
-  let sign = non_zero_0 & (!y_if_non_zero_0.is_zero());
-
-  let mut z = -A;
-  z *= FieldElement::conditional_select(&v, &FieldElement::from(1u8), sign);
-  #[allow(non_snake_case)]
-  let Z = z + w;
-  #[allow(non_snake_case)]
-  let mut Y = z - w;
-
-  Y = Y * Z.invert().unwrap();
-  let mut bytes = Y.to_repr();
-  bytes[31] |= sign.unwrap_u8() << 7;
-
-  CompressedEdwardsY(bytes).decompress().unwrap().mul_by_cofactor()
+/// Monero's hash to point function, as named `ge_fromfe_frombytes_vartime`.
+pub fn hash_to_point(key: EdwardsPoint) -> EdwardsPoint {
+  raw_hash_to_point(key.compress().to_bytes())
 }

coins/monero/src/ringct/mlsag.rs

@@ -0,0 +1,72 @@
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
+
+use curve25519_dalek::scalar::Scalar;
+#[cfg(feature = "experimental")]
+use curve25519_dalek::edwards::EdwardsPoint;
+
+use crate::serialize::*;
+#[cfg(feature = "experimental")]
+use crate::{hash_to_scalar, ringct::hash_to_point};
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct Mlsag {
+  pub ss: Vec<[Scalar; 2]>,
+  pub cc: Scalar,
+}
+
+impl Mlsag {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    for ss in &self.ss {
+      write_raw_vec(write_scalar, ss, w)?;
+    }
+    write_scalar(&self.cc, w)
+  }
+
+  pub fn read<R: Read>(mixins: usize, r: &mut R) -> io::Result<Self> {
+    Ok(Self {
+      ss: (0 .. mixins).map(|_| read_array(read_scalar, r)).collect::<Result<_, _>>()?,
+      cc: read_scalar(r)?,
+    })
+  }
+
+  #[cfg(feature = "experimental")]
+  #[must_use]
+  pub fn verify(
+    &self,
+    msg: &[u8; 32],
+    ring: &[[EdwardsPoint; 2]],
+    key_image: &EdwardsPoint,
+  ) -> bool {
+    if ring.is_empty() {
+      return false;
+    }
+
+    let mut buf = Vec::with_capacity(6 * 32);
+    let mut ci = self.cc;
+    for (i, ring_member) in ring.iter().enumerate() {
+      buf.extend_from_slice(msg);
+
+      #[allow(non_snake_case)]
+      let L =
+        |r| EdwardsPoint::vartime_double_scalar_mul_basepoint(&ci, &ring_member[r], &self.ss[i][r]);
+
+      buf.extend_from_slice(ring_member[0].compress().as_bytes());
+      buf.extend_from_slice(L(0).compress().as_bytes());
+
+      #[allow(non_snake_case)]
+      let R = (self.ss[i][0] * hash_to_point(ring_member[0])) + (ci * key_image);
+      buf.extend_from_slice(R.compress().as_bytes());
+
+      buf.extend_from_slice(ring_member[1].compress().as_bytes());
+      buf.extend_from_slice(L(1).compress().as_bytes());
+
+      ci = hash_to_scalar(&buf);
+      buf.clear();
+    }
+
+    ci == self.cc
+  }
+}

coins/monero/src/ringct/mod.rs

@@ -1,25 +1,121 @@
+use core::ops::Deref;
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
+
+use zeroize::{Zeroize, Zeroizing};
+
 use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, scalar::Scalar, edwards::EdwardsPoint};
 
 pub(crate) mod hash_to_point;
-pub use hash_to_point::hash_to_point;
+pub use hash_to_point::{raw_hash_to_point, hash_to_point};
 
+/// MLSAG struct, along with verifying functionality.
+pub mod mlsag;
+/// CLSAG struct, along with signing and verifying functionality.
 pub mod clsag;
+/// BorromeanRange struct, along with verifying functionality.
+pub mod borromean;
+/// Bulletproofs(+) structs, along with proving and verifying functionality.
 pub mod bulletproofs;
 
 use crate::{
+  Protocol,
   serialize::*,
-  ringct::{clsag::Clsag, bulletproofs::Bulletproofs}
+  ringct::{mlsag::Mlsag, clsag::Clsag, borromean::BorromeanRange, bulletproofs::Bulletproofs},
 };
 
-pub fn generate_key_image(secret: Scalar) -> EdwardsPoint {
-  secret * hash_to_point(&secret * &ED25519_BASEPOINT_TABLE)
+/// Generate a key image for a given key. Defined as `x * hash_to_point(xG)`.
+pub fn generate_key_image(secret: &Zeroizing<Scalar>) -> EdwardsPoint {
+  hash_to_point(&ED25519_BASEPOINT_TABLE * secret.deref()) * secret.deref()
 }
 
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub enum EncryptedAmount {
+  Original { mask: [u8; 32], amount: [u8; 32] },
+  Compact { amount: [u8; 8] },
+}
+
+impl EncryptedAmount {
+  pub fn read<R: Read>(compact: bool, r: &mut R) -> io::Result<Self> {
+    Ok(if compact {
+      Self::Compact { amount: read_bytes(r)? }
+    } else {
+      Self::Original { mask: read_bytes(r)?, amount: read_bytes(r)? }
+    })
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    match self {
+      Self::Original { mask, amount } => {
+        w.write_all(mask)?;
+        w.write_all(amount)
+      }
+      Self::Compact { amount } => w.write_all(amount),
+    }
+  }
+}
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
+pub enum RctType {
+  /// No RCT proofs.
+  Null,
+  /// One MLSAG for a single input and a Borromean range proof (RCTTypeFull).
+  MlsagAggregate,
+  // One MLSAG for each input and a Borromean range proof (RCTTypeSimple).
+  MlsagIndividual,
+  // One MLSAG for each input and a Bulletproof (RCTTypeBulletproof).
+  Bulletproofs,
+  /// One MLSAG for each input and a Bulletproof, yet starting to use EncryptedAmount::Compact
+  /// (RCTTypeBulletproof2).
+  BulletproofsCompactAmount,
+  /// One CLSAG for each input and a Bulletproof (RCTTypeCLSAG).
+  Clsag,
+  /// One CLSAG for each input and a Bulletproof+ (RCTTypeBulletproofPlus).
+  BulletproofsPlus,
+}
+
+impl RctType {
+  pub fn to_byte(self) -> u8 {
+    match self {
+      Self::Null => 0,
+      Self::MlsagAggregate => 1,
+      Self::MlsagIndividual => 2,
+      Self::Bulletproofs => 3,
+      Self::BulletproofsCompactAmount => 4,
+      Self::Clsag => 5,
+      Self::BulletproofsPlus => 6,
+    }
+  }
+
+  pub fn from_byte(byte: u8) -> Option<Self> {
+    Some(match byte {
+      0 => Self::Null,
+      1 => Self::MlsagAggregate,
+      2 => Self::MlsagIndividual,
+      3 => Self::Bulletproofs,
+      4 => Self::BulletproofsCompactAmount,
+      5 => Self::Clsag,
+      6 => Self::BulletproofsPlus,
+      _ => None?,
+    })
+  }
+
+  pub fn compact_encrypted_amounts(&self) -> bool {
+    match self {
+      Self::Null | Self::MlsagAggregate | Self::MlsagIndividual | Self::Bulletproofs => false,
+      Self::BulletproofsCompactAmount | Self::Clsag | Self::BulletproofsPlus => true,
+    }
+  }
+}
+
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct RctBase {
   pub fee: u64,
-  pub ecdh_info: Vec<[u8; 8]>,
-  pub commitments: Vec<EdwardsPoint>
+  pub pseudo_outs: Vec<EdwardsPoint>,
+  pub encrypted_amounts: Vec<EncryptedAmount>,
+  pub commitments: Vec<EdwardsPoint>,
 }
 
 impl RctBase {
@@ -27,119 +123,261 @@ impl RctBase {
     1 + 8 + (outputs * (8 + 32))
   }
 
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W, rct_type: u8) -> std::io::Result<()> {
-    w.write_all(&[rct_type])?;
+  pub fn write<W: Write>(&self, w: &mut W, rct_type: RctType) -> io::Result<()> {
+    w.write_all(&[rct_type.to_byte()])?;
     match rct_type {
-      0 => Ok(()),
-      5 => {
+      RctType::Null => Ok(()),
+      RctType::MlsagAggregate |
+      RctType::MlsagIndividual |
+      RctType::Bulletproofs |
+      RctType::BulletproofsCompactAmount |
+      RctType::Clsag |
+      RctType::BulletproofsPlus => {
         write_varint(&self.fee, w)?;
-        for ecdh in &self.ecdh_info {
-          w.write_all(ecdh)?;
+        if rct_type == RctType::MlsagIndividual {
+          write_raw_vec(write_point, &self.pseudo_outs, w)?;
+        }
+        for encrypted_amount in &self.encrypted_amounts {
+          encrypted_amount.write(w)?;
         }
         write_raw_vec(write_point, &self.commitments, w)
-      },
-      _ => panic!("Serializing unknown RctType's Base")
+      }
     }
   }
 
-  pub fn deserialize<R: std::io::Read>(outputs: usize, r: &mut R) -> std::io::Result<(RctBase, u8)> {
-    let mut rct_type = [0];
-    r.read_exact(&mut rct_type)?;
+  pub fn read<R: Read>(inputs: usize, outputs: usize, r: &mut R) -> io::Result<(Self, RctType)> {
+    let rct_type = RctType::from_byte(read_byte(r)?)
+      .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "invalid RCT type"))?;
+
+    match rct_type {
+      RctType::Null | RctType::MlsagAggregate | RctType::MlsagIndividual => {}
+      RctType::Bulletproofs |
+      RctType::BulletproofsCompactAmount |
+      RctType::Clsag |
+      RctType::BulletproofsPlus => {
+        if outputs == 0 {
+          // Because the Bulletproofs(+) layout must be canonical, there must be 1 Bulletproof if
+          // Bulletproofs are in use
+          // If there are Bulletproofs, there must be a matching amount of outputs, implicitly
+          // banning 0 outputs
+          // Since HF 12 (CLSAG being 13), a 2-output minimum has also been enforced
+          Err(io::Error::new(io::ErrorKind::Other, "RCT with Bulletproofs(+) had 0 outputs"))?;
+        }
+      }
+    }
+
     Ok((
-      if rct_type[0] == 0 {
-        RctBase { fee: 0, ecdh_info: vec![], commitments: vec![] }
+      if rct_type == RctType::Null {
+        Self { fee: 0, pseudo_outs: vec![], encrypted_amounts: vec![], commitments: vec![] }
       } else {
-        RctBase {
+        Self {
           fee: read_varint(r)?,
-          ecdh_info: (0 .. outputs).map(
-            |_| { let mut ecdh = [0; 8]; r.read_exact(&mut ecdh).map(|_| ecdh) }
-          ).collect::<Result<_, _>>()?,
-          commitments: read_raw_vec(read_point, outputs, r)?
+          pseudo_outs: if rct_type == RctType::MlsagIndividual {
+            read_raw_vec(read_point, inputs, r)?
+          } else {
+            vec![]
+          },
+          encrypted_amounts: (0 .. outputs)
+            .map(|_| EncryptedAmount::read(rct_type.compact_encrypted_amounts(), r))
+            .collect::<Result<_, _>>()?,
+          commitments: read_raw_vec(read_point, outputs, r)?,
         }
       },
-      rct_type[0]
+      rct_type,
     ))
   }
 }
 
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub enum RctPrunable {
   Null,
+  MlsagBorromean {
+    borromean: Vec<BorromeanRange>,
+    mlsags: Vec<Mlsag>,
+  },
+  MlsagBulletproofs {
+    bulletproofs: Bulletproofs,
+    mlsags: Vec<Mlsag>,
+    pseudo_outs: Vec<EdwardsPoint>,
+  },
   Clsag {
-    bulletproofs: Vec<Bulletproofs>,
+    bulletproofs: Bulletproofs,
     clsags: Vec<Clsag>,
-    pseudo_outs: Vec<EdwardsPoint>
-  }
+    pseudo_outs: Vec<EdwardsPoint>,
+  },
 }
 
 impl RctPrunable {
-  pub fn rct_type(&self) -> u8 {
-    match self {
-      RctPrunable::Null => 0,
-      RctPrunable::Clsag { .. } => 5
-    }
+  pub(crate) fn fee_weight(protocol: Protocol, inputs: usize, outputs: usize) -> usize {
+    1 + Bulletproofs::fee_weight(protocol.bp_plus(), outputs) +
+      (inputs * (Clsag::fee_weight(protocol.ring_len()) + 32))
   }
 
-  pub(crate) fn fee_weight(inputs: usize, outputs: usize) -> usize {
-    1 + Bulletproofs::fee_weight(outputs) + (inputs * (Clsag::fee_weight() + 32))
-  }
-
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
+  pub fn write<W: Write>(&self, w: &mut W, rct_type: RctType) -> io::Result<()> {
     match self {
-      RctPrunable::Null => Ok(()),
-      RctPrunable::Clsag { bulletproofs, clsags, pseudo_outs } => {
-        write_vec(Bulletproofs::serialize, &bulletproofs, w)?;
-        write_raw_vec(Clsag::serialize, &clsags, w)?;
-        write_raw_vec(write_point, &pseudo_outs, w)
+      Self::Null => Ok(()),
+      Self::MlsagBorromean { borromean, mlsags } => {
+        write_raw_vec(BorromeanRange::write, borromean, w)?;
+        write_raw_vec(Mlsag::write, mlsags, w)
+      }
+      Self::MlsagBulletproofs { bulletproofs, mlsags, pseudo_outs } => {
+        if rct_type == RctType::Bulletproofs {
+          w.write_all(&1u32.to_le_bytes())?;
+        } else {
+          w.write_all(&[1])?;
+        }
+        bulletproofs.write(w)?;
+
+        write_raw_vec(Mlsag::write, mlsags, w)?;
+        write_raw_vec(write_point, pseudo_outs, w)
+      }
+      Self::Clsag { bulletproofs, clsags, pseudo_outs } => {
+        w.write_all(&[1])?;
+        bulletproofs.write(w)?;
+
+        write_raw_vec(Clsag::write, clsags, w)?;
+        write_raw_vec(write_point, pseudo_outs, w)
       }
     }
   }
 
-  pub fn deserialize<R: std::io::Read>(
-    rct_type: u8,
+  pub fn serialize(&self, rct_type: RctType) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized, rct_type).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(
+    rct_type: RctType,
     decoys: &[usize],
-    r: &mut R
-  ) -> std::io::Result<RctPrunable> {
-    Ok(
-      match rct_type {
-        0 => RctPrunable::Null,
-        5 => RctPrunable::Clsag {
-          // TODO: Can the amount of outputs be calculated from the BPs for any validly formed TX?
-          bulletproofs: read_vec(Bulletproofs::deserialize, r)?,
-          clsags: (0 .. decoys.len()).map(|o| Clsag::deserialize(decoys[o], r)).collect::<Result<_, _>>()?,
-          pseudo_outs: read_raw_vec(read_point, decoys.len(), r)?
+    outputs: usize,
+    r: &mut R,
+  ) -> io::Result<Self> {
+    Ok(match rct_type {
+      RctType::Null => Self::Null,
+      RctType::MlsagAggregate | RctType::MlsagIndividual => Self::MlsagBorromean {
+        borromean: read_raw_vec(BorromeanRange::read, outputs, r)?,
+        mlsags: decoys.iter().map(|d| Mlsag::read(*d, r)).collect::<Result<_, _>>()?,
+      },
+      RctType::Bulletproofs | RctType::BulletproofsCompactAmount => Self::MlsagBulletproofs {
+        bulletproofs: {
+          if (if rct_type == RctType::Bulletproofs {
+            u64::from(read_u32(r)?)
+          } else {
+            read_varint(r)?
+          }) != 1
+          {
+            Err(io::Error::new(io::ErrorKind::Other, "n bulletproofs instead of one"))?;
+          }
+          Bulletproofs::read(r)?
         },
-        _ => Err(std::io::Error::new(std::io::ErrorKind::Other, "Tried to deserialize unknown RCT type"))?
-      }
-    )
+        mlsags: decoys.iter().map(|d| Mlsag::read(*d, r)).collect::<Result<_, _>>()?,
+        pseudo_outs: read_raw_vec(read_point, decoys.len(), r)?,
+      },
+      RctType::Clsag | RctType::BulletproofsPlus => Self::Clsag {
+        bulletproofs: {
+          if read_varint(r)? != 1 {
+            Err(io::Error::new(io::ErrorKind::Other, "n bulletproofs instead of one"))?;
+          }
+          (if rct_type == RctType::Clsag { Bulletproofs::read } else { Bulletproofs::read_plus })(
+            r,
+          )?
+        },
+        clsags: (0 .. decoys.len()).map(|o| Clsag::read(decoys[o], r)).collect::<Result<_, _>>()?,
+        pseudo_outs: read_raw_vec(read_point, decoys.len(), r)?,
+      },
+    })
   }
 
-  pub fn signature_serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
+  pub(crate) fn signature_write<W: Write>(&self, w: &mut W) -> io::Result<()> {
     match self {
-      RctPrunable::Null => panic!("Serializing RctPrunable::Null for a signature"),
-      RctPrunable::Clsag { bulletproofs, .. } => bulletproofs.iter().map(|bp| bp.signature_serialize(w)).collect(),
+      Self::Null => panic!("Serializing RctPrunable::Null for a signature"),
+      Self::MlsagBorromean { borromean, .. } => borromean.iter().try_for_each(|rs| rs.write(w)),
+      Self::MlsagBulletproofs { bulletproofs, .. } => bulletproofs.signature_write(w),
+      Self::Clsag { bulletproofs, .. } => bulletproofs.signature_write(w),
     }
   }
 }
 
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct RctSignatures {
   pub base: RctBase,
-  pub prunable: RctPrunable
+  pub prunable: RctPrunable,
 }
 
 impl RctSignatures {
-  pub(crate) fn fee_weight(inputs: usize, outputs: usize) -> usize {
-    RctBase::fee_weight(outputs) + RctPrunable::fee_weight(inputs, outputs)
+  /// RctType for a given RctSignatures struct.
+  pub fn rct_type(&self) -> RctType {
+    match &self.prunable {
+      RctPrunable::Null => RctType::Null,
+      RctPrunable::MlsagBorromean { .. } => {
+        /*
+          This type of RctPrunable may have no outputs, yet pseudo_outs are per input
+          This will only be a valid RctSignatures if it's for a TX with inputs
+          That makes this valid for any valid RctSignatures
+
+          While it will be invalid for any invalid RctSignatures, potentially letting an invalid
+          MlsagAggregate be interpreted as a valid MlsagIndividual (or vice versa), they have
+          incompatible deserializations
+
+          This means it's impossible to receive a MlsagAggregate over the wire and interpret it
+          as a MlsagIndividual (or vice versa)
+
+          That only makes manual manipulation unsafe, which will always be true since these fields
+          are all pub
+
+          TODO: Consider making them private with read-only accessors?
+        */
+        if self.base.pseudo_outs.is_empty() {
+          RctType::MlsagAggregate
+        } else {
+          RctType::MlsagIndividual
+        }
+      }
+      // RctBase ensures there's at least one output, making the following
+      // inferences guaranteed/expects impossible on any valid RctSignatures
+      RctPrunable::MlsagBulletproofs { .. } => {
+        if matches!(
+          self
+            .base
+            .encrypted_amounts
+            .get(0)
+            .expect("MLSAG with Bulletproofs didn't have any outputs"),
+          EncryptedAmount::Original { .. }
+        ) {
+          RctType::Bulletproofs
+        } else {
+          RctType::BulletproofsCompactAmount
+        }
+      }
+      RctPrunable::Clsag { bulletproofs, .. } => {
+        if matches!(bulletproofs, Bulletproofs::Original { .. }) {
+          RctType::Clsag
+        } else {
+          RctType::BulletproofsPlus
+        }
+      }
+    }
   }
 
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
-    self.base.serialize(w, self.prunable.rct_type())?;
-    self.prunable.serialize(w)
+  pub(crate) fn fee_weight(protocol: Protocol, inputs: usize, outputs: usize) -> usize {
+    RctBase::fee_weight(outputs) + RctPrunable::fee_weight(protocol, inputs, outputs)
   }
 
-  pub fn deserialize<R: std::io::Read>(decoys: Vec<usize>, outputs: usize, r: &mut R) -> std::io::Result<RctSignatures> {
-    let base = RctBase::deserialize(outputs, r)?;
-    Ok(RctSignatures { base: base.0, prunable: RctPrunable::deserialize(base.1, &decoys, r)? })
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    let rct_type = self.rct_type();
+    self.base.write(w, rct_type)?;
+    self.prunable.write(w, rct_type)
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(decoys: Vec<usize>, outputs: usize, r: &mut R) -> io::Result<Self> {
+    let base = RctBase::read(decoys.len(), outputs, r)?;
+    Ok(Self { base: base.0, prunable: RctPrunable::read(base.1, &decoys, outputs, r)? })
   }
 }

coins/monero/src/rpc.rs

@@ -1,353 +0,0 @@
-use std::fmt::Debug;
-
-use thiserror::Error;
-
-use curve25519_dalek::edwards::{EdwardsPoint, CompressedEdwardsY};
-
-use serde::{Serialize, Deserialize, de::DeserializeOwned};
-use serde_json::json;
-
-use reqwest;
-
-use crate::{transaction::{Input, Timelock, Transaction}, block::Block, wallet::Fee};
-
-#[derive(Deserialize, Debug)]
-pub struct EmptyResponse {}
-#[derive(Deserialize, Debug)]
-pub struct JsonRpcResponse<T> {
-  result: T
-}
-
-#[derive(Clone, Error, Debug)]
-pub enum RpcError {
-  #[error("internal error ({0})")]
-  InternalError(String),
-  #[error("connection error")]
-  ConnectionError,
-  #[error("transactions not found")]
-  TransactionsNotFound(Vec<[u8; 32]>),
-  #[error("invalid point ({0})")]
-  InvalidPoint(String),
-  #[error("pruned transaction")]
-  PrunedTransaction,
-  #[error("invalid transaction ({0:?})")]
-  InvalidTransaction([u8; 32])
-}
-
-fn rpc_hex(value: &str) -> Result<Vec<u8>, RpcError> {
-  hex::decode(value).map_err(|_| RpcError::InternalError("Monero returned invalid hex".to_string()))
-}
-
-fn rpc_point(point: &str) -> Result<EdwardsPoint, RpcError> {
-  CompressedEdwardsY(
-    rpc_hex(point)?.try_into().map_err(|_| RpcError::InvalidPoint(point.to_string()))?
-  ).decompress().ok_or(RpcError::InvalidPoint(point.to_string()))
-}
-
-#[derive(Clone, Debug)]
-pub struct Rpc(String);
-
-impl Rpc {
-  pub fn new(daemon: String) -> Rpc {
-    Rpc(daemon)
-  }
-
-  pub async fn rpc_call<
-    Params: Serialize + Debug,
-    Response: DeserializeOwned + Debug
-  >(&self, method: &str, params: Option<Params>) -> Result<Response, RpcError> {
-    let client = reqwest::Client::new();
-    let mut builder = client.post(&(self.0.clone() + "/" + method));
-    if let Some(params) = params.as_ref() {
-      builder = builder.json(params);
-    }
-
-    self.call_tail(method, builder).await
-  }
-
-  pub async fn bin_call<
-    Response: DeserializeOwned + Debug
-  >(&self, method: &str, params: Vec<u8>) -> Result<Response, RpcError> {
-    let client = reqwest::Client::new();
-    let builder = client.post(&(self.0.clone() + "/" + method)).body(params);
-    self.call_tail(method, builder.header("Content-Type", "application/octet-stream")).await
-  }
-
-  async fn call_tail<
-    Response: DeserializeOwned + Debug
-  >(&self, method: &str, builder: reqwest::RequestBuilder) -> Result<Response, RpcError> {
-    let res = builder
-      .send()
-      .await
-      .map_err(|_| RpcError::ConnectionError)?;
-
-    Ok(
-      if !method.ends_with(".bin") {
-        serde_json::from_str(&res.text().await.map_err(|_| RpcError::ConnectionError)?)
-          .map_err(|_| RpcError::InternalError("Failed to parse JSON response".to_string()))?
-      } else {
-        monero_epee_bin_serde::from_bytes(&res.bytes().await.map_err(|_| RpcError::ConnectionError)?)
-          .map_err(|_| RpcError::InternalError("Failed to parse binary response".to_string()))?
-      }
-    )
-  }
-
-  pub async fn get_height(&self) -> Result<usize, RpcError> {
-    #[derive(Deserialize, Debug)]
-    struct HeightResponse {
-      height: usize
-    }
-    Ok(self.rpc_call::<Option<()>, HeightResponse>("get_height", None).await?.height)
-  }
-
-  async fn get_transactions_core(
-    &self,
-    hashes: &[[u8; 32]]
-  ) -> Result<(Vec<Result<Transaction, RpcError>>, Vec<[u8; 32]>), RpcError> {
-    if hashes.len() == 0 {
-      return Ok((vec![], vec![]));
-    }
-
-    #[derive(Deserialize, Debug)]
-    struct TransactionResponse {
-      tx_hash: String,
-      as_hex: String,
-      pruned_as_hex: String
-    }
-    #[derive(Deserialize, Debug)]
-    struct TransactionsResponse {
-      #[serde(default)]
-      missed_tx: Vec<String>,
-      txs: Vec<TransactionResponse>
-    }
-
-    let txs: TransactionsResponse = self.rpc_call("get_transactions", Some(json!({
-      "txs_hashes": hashes.iter().map(|hash| hex::encode(&hash)).collect::<Vec<_>>()
-    }))).await?;
-
-    Ok((
-      txs.txs.iter().map(|res| {
-        let tx = Transaction::deserialize(
-          &mut std::io::Cursor::new(
-            rpc_hex(if res.as_hex.len() != 0 { &res.as_hex } else { &res.pruned_as_hex }).unwrap()
-          )
-        ).map_err(|_| RpcError::InvalidTransaction(hex::decode(&res.tx_hash).unwrap().try_into().unwrap()))?;
-
-        // https://github.com/monero-project/monero/issues/8311
-        if res.as_hex.len() == 0 {
-          match tx.prefix.inputs.get(0) {
-            Some(Input::Gen { .. }) => (),
-            _ => Err(RpcError::PrunedTransaction)?
-          }
-        }
-
-        Ok(tx)
-      }).collect(),
-
-      txs.missed_tx.iter().map(|hash| hex::decode(&hash).unwrap().try_into().unwrap()).collect()
-    ))
-  }
-
-  pub async fn get_transactions(&self, hashes: &[[u8; 32]]) -> Result<Vec<Transaction>, RpcError> {
-    let (txs, missed) = self.get_transactions_core(hashes).await?;
-    if missed.len() != 0 {
-      Err(RpcError::TransactionsNotFound(missed))?;
-    }
-    // This will clone several KB and is accordingly inefficient
-    // TODO: Optimize
-    txs.iter().cloned().collect::<Result<_, _>>()
-  }
-
-  pub async fn get_transactions_possible(&self, hashes: &[[u8; 32]]) -> Result<Vec<Transaction>, RpcError> {
-    let (txs, _) = self.get_transactions_core(hashes).await?;
-    Ok(txs.iter().cloned().filter_map(|tx| tx.ok()).collect())
-  }
-
-  pub async fn get_block(&self, height: usize) -> Result<Block, RpcError> {
-    #[derive(Deserialize, Debug)]
-    struct BlockResponse {
-      blob: String
-    }
-
-    let block: JsonRpcResponse<BlockResponse> = self.rpc_call("json_rpc", Some(json!({
-      "method": "get_block",
-      "params": {
-        "height": height
-      }
-    }))).await?;
-
-    Ok(
-      Block::deserialize(
-        &mut std::io::Cursor::new(rpc_hex(&block.result.blob)?)
-      ).expect("Monero returned a block we couldn't deserialize")
-    )
-  }
-
-  async fn get_block_transactions_core(
-    &self,
-    height: usize,
-    possible: bool
-  ) -> Result<Vec<Transaction>, RpcError> {
-    let block = self.get_block(height).await?;
-    let mut res = vec![block.miner_tx];
-    res.extend(
-      if possible {
-        self.get_transactions_possible(&block.txs).await?
-      } else {
-        self.get_transactions(&block.txs).await?
-      }
-    );
-    Ok(res)
-  }
-
-  pub async fn get_block_transactions(&self, height: usize) -> Result<Vec<Transaction>, RpcError> {
-    self.get_block_transactions_core(height, false).await
-  }
-
-  pub async fn get_block_transactions_possible(&self, height: usize) -> Result<Vec<Transaction>, RpcError> {
-    self.get_block_transactions_core(height, true).await
-  }
-
-  pub async fn get_o_indexes(&self, hash: [u8; 32]) -> Result<Vec<u64>, RpcError> {
-    #[derive(Serialize, Debug)]
-    struct Request {
-      txid: [u8; 32]
-    }
-
-    #[allow(dead_code)]
-    #[derive(Deserialize, Debug)]
-    struct OIndexes {
-      o_indexes: Vec<u64>,
-      status: String,
-      untrusted: bool,
-      credits: usize,
-      top_hash: String
-    }
-
-    let indexes: OIndexes = self.bin_call("get_o_indexes.bin", monero_epee_bin_serde::to_bytes(
-      &Request {
-        txid: hash
-      }).unwrap()
-    ).await?;
-
-    Ok(indexes.o_indexes)
-  }
-
-  // from and to are inclusive
-  pub async fn get_output_distribution(&self, from: usize, to: usize) -> Result<Vec<u64>, RpcError> {
-    #[allow(dead_code)]
-    #[derive(Deserialize, Debug)]
-    pub struct Distribution {
-      distribution: Vec<u64>
-    }
-
-    #[allow(dead_code)]
-    #[derive(Deserialize, Debug)]
-    struct Distributions {
-      distributions: Vec<Distribution>
-    }
-
-    let mut distributions: JsonRpcResponse<Distributions> = self.rpc_call("json_rpc", Some(json!({
-      "method": "get_output_distribution",
-      "params": {
-        "binary": false,
-        "amounts": [0],
-        "cumulative": true,
-        "from_height": from,
-        "to_height": to
-      }
-    }))).await?;
-
-    Ok(distributions.result.distributions.swap_remove(0).distribution)
-  }
-
-  pub async fn get_outputs(
-    &self,
-    indexes: &[u64],
-    height: usize
-  ) -> Result<Vec<Option<[EdwardsPoint; 2]>>, RpcError> {
-    #[derive(Deserialize, Debug)]
-    pub struct Out {
-      key: String,
-      mask: String,
-      txid: String
-    }
-
-    #[derive(Deserialize, Debug)]
-    struct Outs {
-      outs: Vec<Out>
-    }
-
-    let outs: Outs = self.rpc_call("get_outs", Some(json!({
-      "get_txid": true,
-      "outputs": indexes.iter().map(|o| json!({
-        "amount": 0,
-        "index": o
-      })).collect::<Vec<_>>()
-    }))).await?;
-
-    let txs = self.get_transactions(
-      &outs.outs.iter().map(|out|
-        rpc_hex(&out.txid).expect("Monero returned an invalidly encoded hash")
-          .try_into().expect("Monero returned an invalid sized hash")
-      ).collect::<Vec<_>>()
-    ).await?;
-    // TODO: Support time based lock times. These shouldn't be needed, and it may be painful to
-    // get the median time for the given height, yet we do need to in order to be complete
-    outs.outs.iter().enumerate().map(
-      |(i, out)| Ok(
-        Some([rpc_point(&out.key)?, rpc_point(&out.mask)?]).filter(|_| {
-          match txs[i].prefix.timelock {
-            Timelock::Block(t_height) => (t_height <= height),
-            _ => false
-          }
-        })
-      )
-    ).collect()
-  }
-
-  pub async fn get_fee(&self) -> Result<Fee, RpcError> {
-    #[allow(dead_code)]
-    #[derive(Deserialize, Debug)]
-    struct FeeResponse {
-      fee: u64,
-      quantization_mask: u64
-    }
-
-    let res: JsonRpcResponse<FeeResponse> = self.rpc_call("json_rpc", Some(json!({
-      "method": "get_fee_estimate"
-    }))).await?;
-
-    Ok(Fee { per_weight: res.result.fee, mask: res.result.quantization_mask })
-  }
-
-  pub async fn publish_transaction(&self, tx: &Transaction) -> Result<(), RpcError> {
-    #[allow(dead_code)]
-    #[derive(Deserialize, Debug)]
-    struct SendRawResponse {
-      status: String,
-      double_spend: bool,
-      fee_too_low: bool,
-      invalid_input: bool,
-      invalid_output: bool,
-      low_mixin: bool,
-      not_relayed: bool,
-      overspend: bool,
-      too_big: bool,
-      too_few_outputs: bool,
-      reason: String
-    }
-
-    let mut buf = Vec::with_capacity(2048);
-    tx.serialize(&mut buf).unwrap();
-    let res: SendRawResponse = self.rpc_call("send_raw_transaction", Some(json!({
-      "tx_as_hex": hex::encode(&buf)
-    }))).await?;
-
-    if res.status != "OK" {
-      Err(RpcError::InvalidTransaction(tx.hash()))?;
-    }
-
-    Ok(())
-  }
-}

coins/monero/src/rpc/http.rs

@@ -0,0 +1,91 @@
+use async_trait::async_trait;
+
+use digest_auth::AuthContext;
+use reqwest::Client;
+
+use crate::rpc::{RpcError, RpcConnection, Rpc};
+
+#[derive(Clone, Debug)]
+pub struct HttpRpc {
+  client: Client,
+  userpass: Option<(String, String)>,
+  url: String,
+}
+
+impl HttpRpc {
+  /// Create a new HTTP(S) RPC connection.
+  ///
+  /// A daemon requiring authentication can be used via including the username and password in the
+  /// URL.
+  pub fn new(mut url: String) -> Result<Rpc<Self>, RpcError> {
+    // Parse out the username and password
+    let userpass = if url.contains('@') {
+      let url_clone = url;
+      let split_url = url_clone.split('@').collect::<Vec<_>>();
+      if split_url.len() != 2 {
+        Err(RpcError::InvalidNode)?;
+      }
+      let mut userpass = split_url[0];
+      url = split_url[1].to_string();
+
+      // If there was additionally a protocol string, restore that to the daemon URL
+      if userpass.contains("://") {
+        let split_userpass = userpass.split("://").collect::<Vec<_>>();
+        if split_userpass.len() != 2 {
+          Err(RpcError::InvalidNode)?;
+        }
+        url = split_userpass[0].to_string() + "://" + &url;
+        userpass = split_userpass[1];
+      }
+
+      let split_userpass = userpass.split(':').collect::<Vec<_>>();
+      if split_userpass.len() != 2 {
+        Err(RpcError::InvalidNode)?;
+      }
+      Some((split_userpass[0].to_string(), split_userpass[1].to_string()))
+    } else {
+      None
+    };
+
+    Ok(Rpc(Self { client: Client::new(), userpass, url }))
+  }
+}
+
+#[async_trait]
+impl RpcConnection for HttpRpc {
+  async fn post(&self, route: &str, body: Vec<u8>) -> Result<Vec<u8>, RpcError> {
+    let mut builder = self.client.post(self.url.clone() + "/" + route).body(body);
+
+    if let Some((user, pass)) = &self.userpass {
+      let req = self.client.post(&self.url).send().await.map_err(|_| RpcError::InvalidNode)?;
+      // Only provide authentication if this daemon actually expects it
+      if let Some(header) = req.headers().get("www-authenticate") {
+        builder = builder.header(
+          "Authorization",
+          digest_auth::parse(header.to_str().map_err(|_| RpcError::InvalidNode)?)
+            .map_err(|_| RpcError::InvalidNode)?
+            .respond(&AuthContext::new_post::<_, _, _, &[u8]>(
+              user,
+              pass,
+              "/".to_string() + route,
+              None,
+            ))
+            .map_err(|_| RpcError::InvalidNode)?
+            .to_header_string(),
+        );
+      }
+    }
+
+    Ok(
+      builder
+        .send()
+        .await
+        .map_err(|_| RpcError::ConnectionError)?
+        .bytes()
+        .await
+        .map_err(|_| RpcError::ConnectionError)?
+        .slice(..)
+        .to_vec(),
+    )
+  }
+}

coins/monero/src/rpc/mod.rs

@@ -0,0 +1,617 @@
+use core::fmt::Debug;
+#[cfg(not(feature = "std"))]
+use alloc::boxed::Box;
+use std_shims::{
+  vec::Vec,
+  io,
+  string::{String, ToString},
+};
+
+use async_trait::async_trait;
+
+use curve25519_dalek::edwards::{EdwardsPoint, CompressedEdwardsY};
+
+use serde::{Serialize, Deserialize, de::DeserializeOwned};
+use serde_json::{Value, json};
+
+use crate::{
+  Protocol,
+  serialize::*,
+  transaction::{Input, Timelock, Transaction},
+  block::Block,
+  wallet::Fee,
+};
+
+#[cfg(feature = "http_rpc")]
+mod http;
+#[cfg(feature = "http_rpc")]
+pub use http::*;
+
+#[derive(Deserialize, Debug)]
+pub struct EmptyResponse;
+#[derive(Deserialize, Debug)]
+pub struct JsonRpcResponse<T> {
+  result: T,
+}
+
+#[derive(Deserialize, Debug)]
+struct TransactionResponse {
+  tx_hash: String,
+  as_hex: String,
+  pruned_as_hex: String,
+}
+#[derive(Deserialize, Debug)]
+struct TransactionsResponse {
+  #[serde(default)]
+  missed_tx: Vec<String>,
+  txs: Vec<TransactionResponse>,
+}
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+#[cfg_attr(feature = "std", derive(thiserror::Error))]
+pub enum RpcError {
+  #[cfg_attr(feature = "std", error("internal error ({0})"))]
+  InternalError(&'static str),
+  #[cfg_attr(feature = "std", error("connection error"))]
+  ConnectionError,
+  #[cfg_attr(feature = "std", error("invalid node"))]
+  InvalidNode,
+  #[cfg_attr(feature = "std", error("unsupported protocol version ({0})"))]
+  UnsupportedProtocol(usize),
+  #[cfg_attr(feature = "std", error("transactions not found"))]
+  TransactionsNotFound(Vec<[u8; 32]>),
+  #[cfg_attr(feature = "std", error("invalid point ({0})"))]
+  InvalidPoint(String),
+  #[cfg_attr(feature = "std", error("pruned transaction"))]
+  PrunedTransaction,
+  #[cfg_attr(feature = "std", error("invalid transaction ({0:?})"))]
+  InvalidTransaction([u8; 32]),
+}
+
+fn rpc_hex(value: &str) -> Result<Vec<u8>, RpcError> {
+  hex::decode(value).map_err(|_| RpcError::InvalidNode)
+}
+
+fn hash_hex(hash: &str) -> Result<[u8; 32], RpcError> {
+  rpc_hex(hash)?.try_into().map_err(|_| RpcError::InvalidNode)
+}
+
+fn rpc_point(point: &str) -> Result<EdwardsPoint, RpcError> {
+  CompressedEdwardsY(
+    rpc_hex(point)?.try_into().map_err(|_| RpcError::InvalidPoint(point.to_string()))?,
+  )
+  .decompress()
+  .ok_or_else(|| RpcError::InvalidPoint(point.to_string()))
+}
+
+// Read an EPEE VarInt, distinct from the VarInts used throughout the rest of the protocol
+fn read_epee_vi<R: io::Read>(reader: &mut R) -> io::Result<u64> {
+  let vi_start = read_byte(reader)?;
+  let len = match vi_start & 0b11 {
+    0 => 1,
+    1 => 2,
+    2 => 4,
+    3 => 8,
+    _ => unreachable!(),
+  };
+  let mut vi = u64::from(vi_start >> 2);
+  for i in 1 .. len {
+    vi |= u64::from(read_byte(reader)?) << (((i - 1) * 8) + 6);
+  }
+  Ok(vi)
+}
+
+#[async_trait]
+pub trait RpcConnection: Send + Sync + Clone + Debug {
+  /// Perform a POST request to the specified route with the specified body.
+  ///
+  /// The implementor is left to handle anything such as authentication.
+  async fn post(&self, route: &str, body: Vec<u8>) -> Result<Vec<u8>, RpcError>;
+}
+
+// TODO: Make this provided methods for RpcConnection?
+#[derive(Clone, Debug)]
+pub struct Rpc<R: RpcConnection>(R);
+impl<R: RpcConnection> Rpc<R> {
+  /// Perform a RPC call to the specified route with the provided parameters.
+  ///
+  /// This is NOT a JSON-RPC call. They use a route of "json_rpc" and are available via
+  /// `json_rpc_call`.
+  pub async fn rpc_call<Params: Send + Serialize + Debug, Response: DeserializeOwned + Debug>(
+    &self,
+    route: &str,
+    params: Option<Params>,
+  ) -> Result<Response, RpcError> {
+    serde_json::from_str(
+      std_shims::str::from_utf8(
+        &self
+          .0
+          .post(
+            route,
+            if let Some(params) = params {
+              serde_json::to_string(&params).unwrap().into_bytes()
+            } else {
+              vec![]
+            },
+          )
+          .await?,
+      )
+      .map_err(|_| RpcError::InvalidNode)?,
+    )
+    .map_err(|_| RpcError::InvalidNode)
+  }
+
+  /// Perform a JSON-RPC call with the specified method with the provided parameters
+  pub async fn json_rpc_call<Response: DeserializeOwned + Debug>(
+    &self,
+    method: &str,
+    params: Option<Value>,
+  ) -> Result<Response, RpcError> {
+    let mut req = json!({ "method": method });
+    if let Some(params) = params {
+      req.as_object_mut().unwrap().insert("params".into(), params);
+    }
+    Ok(self.rpc_call::<_, JsonRpcResponse<Response>>("json_rpc", Some(req)).await?.result)
+  }
+
+  /// Perform a binary call to the specified route with the provided parameters.
+  pub async fn bin_call(&self, route: &str, params: Vec<u8>) -> Result<Vec<u8>, RpcError> {
+    self.0.post(route, params).await
+  }
+
+  /// Get the active blockchain protocol version.
+  pub async fn get_protocol(&self) -> Result<Protocol, RpcError> {
+    #[derive(Deserialize, Debug)]
+    struct ProtocolResponse {
+      major_version: usize,
+    }
+
+    #[derive(Deserialize, Debug)]
+    struct LastHeaderResponse {
+      block_header: ProtocolResponse,
+    }
+
+    Ok(
+      match self
+        .json_rpc_call::<LastHeaderResponse>("get_last_block_header", None)
+        .await?
+        .block_header
+        .major_version
+      {
+        13 | 14 => Protocol::v14,
+        15 | 16 => Protocol::v16,
+        protocol => Err(RpcError::UnsupportedProtocol(protocol))?,
+      },
+    )
+  }
+
+  pub async fn get_height(&self) -> Result<usize, RpcError> {
+    #[derive(Deserialize, Debug)]
+    struct HeightResponse {
+      height: usize,
+    }
+    Ok(self.rpc_call::<Option<()>, HeightResponse>("get_height", None).await?.height)
+  }
+
+  pub async fn get_transactions(&self, hashes: &[[u8; 32]]) -> Result<Vec<Transaction>, RpcError> {
+    if hashes.is_empty() {
+      return Ok(vec![]);
+    }
+
+    let mut hashes_hex = hashes.iter().map(hex::encode).collect::<Vec<_>>();
+    let mut all_txs = Vec::with_capacity(hashes.len());
+    while !hashes_hex.is_empty() {
+      // Monero errors if more than 100 is requested unless using a non-restricted RPC
+      const TXS_PER_REQUEST: usize = 100;
+      let this_count = TXS_PER_REQUEST.min(hashes_hex.len());
+
+      let txs: TransactionsResponse = self
+        .rpc_call(
+          "get_transactions",
+          Some(json!({
+            "txs_hashes": hashes_hex.drain(.. this_count).collect::<Vec<_>>(),
+          })),
+        )
+        .await?;
+
+      if !txs.missed_tx.is_empty() {
+        Err(RpcError::TransactionsNotFound(
+          txs.missed_tx.iter().map(|hash| hash_hex(hash)).collect::<Result<_, _>>()?,
+        ))?;
+      }
+
+      all_txs.extend(txs.txs);
+    }
+
+    all_txs
+      .iter()
+      .enumerate()
+      .map(|(i, res)| {
+        let tx = Transaction::read::<&[u8]>(
+          &mut rpc_hex(if !res.as_hex.is_empty() { &res.as_hex } else { &res.pruned_as_hex })?
+            .as_ref(),
+        )
+        .map_err(|_| match hash_hex(&res.tx_hash) {
+          Ok(hash) => RpcError::InvalidTransaction(hash),
+          Err(err) => err,
+        })?;
+
+        // https://github.com/monero-project/monero/issues/8311
+        if res.as_hex.is_empty() {
+          match tx.prefix.inputs.get(0) {
+            Some(Input::Gen { .. }) => (),
+            _ => Err(RpcError::PrunedTransaction)?,
+          }
+        }
+
+        // This does run a few keccak256 hashes, which is pointless if the node is trusted
+        // In exchange, this provides resilience against invalid/malicious nodes
+        if tx.hash() != hashes[i] {
+          Err(RpcError::InvalidNode)?;
+        }
+
+        Ok(tx)
+      })
+      .collect()
+  }
+
+  pub async fn get_transaction(&self, tx: [u8; 32]) -> Result<Transaction, RpcError> {
+    self.get_transactions(&[tx]).await.map(|mut txs| txs.swap_remove(0))
+  }
+
+  /// Get the hash of a block from the node by the block's numbers.
+  /// This function does not verify the returned block hash is actually for the number in question.
+  pub async fn get_block_hash(&self, number: usize) -> Result<[u8; 32], RpcError> {
+    #[derive(Deserialize, Debug)]
+    struct BlockHeaderResponse {
+      hash: String,
+    }
+    #[derive(Deserialize, Debug)]
+    struct BlockHeaderByHeightResponse {
+      block_header: BlockHeaderResponse,
+    }
+
+    let header: BlockHeaderByHeightResponse =
+      self.json_rpc_call("get_block_header_by_height", Some(json!({ "height": number }))).await?;
+    rpc_hex(&header.block_header.hash)?.try_into().map_err(|_| RpcError::InvalidNode)
+  }
+
+  /// Get a block from the node by its hash.
+  /// This function does not verify the returned block actually has the hash in question.
+  pub async fn get_block(&self, hash: [u8; 32]) -> Result<Block, RpcError> {
+    #[derive(Deserialize, Debug)]
+    struct BlockResponse {
+      blob: String,
+    }
+
+    let res: BlockResponse =
+      self.json_rpc_call("get_block", Some(json!({ "hash": hex::encode(hash) }))).await?;
+
+    let block =
+      Block::read::<&[u8]>(&mut rpc_hex(&res.blob)?.as_ref()).map_err(|_| RpcError::InvalidNode)?;
+    if block.hash() != hash {
+      Err(RpcError::InvalidNode)?;
+    }
+    Ok(block)
+  }
+
+  pub async fn get_block_by_number(&self, number: usize) -> Result<Block, RpcError> {
+    match self.get_block(self.get_block_hash(number).await?).await {
+      Ok(block) => {
+        // Make sure this is actually the block for this number
+        match block.miner_tx.prefix.inputs.get(0) {
+          Some(Input::Gen(actual)) => {
+            if usize::try_from(*actual).unwrap() == number {
+              Ok(block)
+            } else {
+              Err(RpcError::InvalidNode)
+            }
+          }
+          Some(Input::ToKey { .. }) | None => Err(RpcError::InvalidNode),
+        }
+      }
+      e => e,
+    }
+  }
+
+  pub async fn get_block_transactions(&self, hash: [u8; 32]) -> Result<Vec<Transaction>, RpcError> {
+    let block = self.get_block(hash).await?;
+    let mut res = vec![block.miner_tx];
+    res.extend(self.get_transactions(&block.txs).await?);
+    Ok(res)
+  }
+
+  pub async fn get_block_transactions_by_number(
+    &self,
+    number: usize,
+  ) -> Result<Vec<Transaction>, RpcError> {
+    self.get_block_transactions(self.get_block_hash(number).await?).await
+  }
+
+  /// Get the output indexes of the specified transaction.
+  pub async fn get_o_indexes(&self, hash: [u8; 32]) -> Result<Vec<u64>, RpcError> {
+    /*
+    TODO: Use these when a suitable epee serde lib exists
+
+    #[derive(Serialize, Debug)]
+    struct Request {
+      txid: [u8; 32],
+    }
+
+    #[allow(dead_code)]
+    #[derive(Deserialize, Debug)]
+    struct OIndexes {
+      o_indexes: Vec<u64>,
+    }
+    */
+
+    // Given the immaturity of Rust epee libraries, this is a homegrown one which is only validated
+    // to work against this specific function
+
+    // Header for EPEE, an 8-byte magic and a version
+    const EPEE_HEADER: &[u8] = b"\x01\x11\x01\x01\x01\x01\x02\x01\x01";
+
+    let mut request = EPEE_HEADER.to_vec();
+    // Number of fields (shifted over 2 bits as the 2 LSBs are reserved for metadata)
+    request.push(1 << 2);
+    // Length of field name
+    request.push(4);
+    // Field name
+    request.extend(b"txid");
+    // Type of field
+    request.push(10);
+    // Length of string, since this byte array is technically a string
+    request.push(32 << 2);
+    // The "string"
+    request.extend(hash);
+
+    let indexes_buf = self.bin_call("get_o_indexes.bin", request).await?;
+    let mut indexes: &[u8] = indexes_buf.as_ref();
+
+    (|| {
+      if read_bytes::<_, { EPEE_HEADER.len() }>(&mut indexes)? != EPEE_HEADER {
+        Err(io::Error::new(io::ErrorKind::Other, "invalid header"))?;
+      }
+
+      let read_object = |reader: &mut &[u8]| {
+        let fields = read_byte(reader)? >> 2;
+
+        for _ in 0 .. fields {
+          let name_len = read_byte(reader)?;
+          let name = read_raw_vec(read_byte, name_len.into(), reader)?;
+
+          let type_with_array_flag = read_byte(reader)?;
+          let kind = type_with_array_flag & (!0x80);
+
+          let iters = if type_with_array_flag != kind { read_epee_vi(reader)? } else { 1 };
+
+          if (&name == b"o_indexes") && (kind != 5) {
+            Err(io::Error::new(io::ErrorKind::Other, "o_indexes weren't u64s"))?;
+          }
+
+          let f = match kind {
+            // i64
+            1 => |reader: &mut &[u8]| read_raw_vec(read_byte, 8, reader),
+            // i32
+            2 => |reader: &mut &[u8]| read_raw_vec(read_byte, 4, reader),
+            // i16
+            3 => |reader: &mut &[u8]| read_raw_vec(read_byte, 2, reader),
+            // i8
+            4 => |reader: &mut &[u8]| read_raw_vec(read_byte, 1, reader),
+            // u64
+            5 => |reader: &mut &[u8]| read_raw_vec(read_byte, 8, reader),
+            // u32
+            6 => |reader: &mut &[u8]| read_raw_vec(read_byte, 4, reader),
+            // u16
+            7 => |reader: &mut &[u8]| read_raw_vec(read_byte, 2, reader),
+            // u8
+            8 => |reader: &mut &[u8]| read_raw_vec(read_byte, 1, reader),
+            // double
+            9 => |reader: &mut &[u8]| read_raw_vec(read_byte, 8, reader),
+            // string, or any collection of bytes
+            10 => |reader: &mut &[u8]| {
+              let len = read_epee_vi(reader)?;
+              read_raw_vec(
+                read_byte,
+                len
+                  .try_into()
+                  .map_err(|_| io::Error::new(io::ErrorKind::Other, "u64 length exceeded usize"))?,
+                reader,
+              )
+            },
+            // bool
+            11 => |reader: &mut &[u8]| read_raw_vec(read_byte, 1, reader),
+            // object, errors here as it shouldn't be used on this call
+            12 => |_: &mut &[u8]| {
+              Err(io::Error::new(
+                io::ErrorKind::Other,
+                "node used object in reply to get_o_indexes",
+              ))
+            },
+            // array, so far unused
+            13 => |_: &mut &[u8]| {
+              Err(io::Error::new(io::ErrorKind::Other, "node used the unused array type"))
+            },
+            _ => {
+              |_: &mut &[u8]| Err(io::Error::new(io::ErrorKind::Other, "node used an invalid type"))
+            }
+          };
+
+          let mut res = vec![];
+          for _ in 0 .. iters {
+            res.push(f(reader)?);
+          }
+
+          let mut actual_res = Vec::with_capacity(res.len());
+          if &name == b"o_indexes" {
+            for o_index in res {
+              actual_res.push(u64::from_le_bytes(o_index.try_into().map_err(|_| {
+                io::Error::new(io::ErrorKind::Other, "node didn't provide 8 bytes for a u64")
+              })?));
+            }
+            return Ok(actual_res);
+          }
+        }
+
+        // Didn't return a response with o_indexes
+        // TODO: Check if this didn't have o_indexes because it's an error response
+        Err(io::Error::new(io::ErrorKind::Other, "response didn't contain o_indexes"))
+      };
+
+      read_object(&mut indexes)
+    })()
+    .map_err(|_| RpcError::InvalidNode)
+  }
+
+  /// Get the output distribution, from the specified height to the specified height (both
+  /// inclusive).
+  pub async fn get_output_distribution(
+    &self,
+    from: usize,
+    to: usize,
+  ) -> Result<Vec<u64>, RpcError> {
+    #[allow(dead_code)]
+    #[derive(Deserialize, Debug)]
+    struct Distribution {
+      distribution: Vec<u64>,
+    }
+
+    #[allow(dead_code)]
+    #[derive(Deserialize, Debug)]
+    struct Distributions {
+      distributions: Vec<Distribution>,
+    }
+
+    let mut distributions: Distributions = self
+      .json_rpc_call(
+        "get_output_distribution",
+        Some(json!({
+          "binary": false,
+          "amounts": [0],
+          "cumulative": true,
+          "from_height": from,
+          "to_height": to,
+        })),
+      )
+      .await?;
+
+    Ok(distributions.distributions.swap_remove(0).distribution)
+  }
+
+  /// Get the specified outputs from the RingCT (zero-amount) pool, but only return them if their
+  /// timelock has been satisfied. This is distinct from being free of the 10-block lock applied to
+  /// all Monero transactions.
+  pub async fn get_unlocked_outputs(
+    &self,
+    indexes: &[u64],
+    height: usize,
+  ) -> Result<Vec<Option<[EdwardsPoint; 2]>>, RpcError> {
+    #[derive(Deserialize, Debug)]
+    struct Out {
+      key: String,
+      mask: String,
+      txid: String,
+    }
+
+    #[derive(Deserialize, Debug)]
+    struct Outs {
+      outs: Vec<Out>,
+    }
+
+    let outs: Outs = self
+      .rpc_call(
+        "get_outs",
+        Some(json!({
+          "get_txid": true,
+          "outputs": indexes.iter().map(|o| json!({
+            "amount": 0,
+            "index": o
+          })).collect::<Vec<_>>()
+        })),
+      )
+      .await?;
+
+    let txs = self
+      .get_transactions(
+        &outs
+          .outs
+          .iter()
+          .map(|out| rpc_hex(&out.txid)?.try_into().map_err(|_| RpcError::InvalidNode))
+          .collect::<Result<Vec<_>, _>>()?,
+      )
+      .await?;
+
+    // TODO: https://github.com/serai-dex/serai/issues/104
+    outs
+      .outs
+      .iter()
+      .enumerate()
+      .map(|(i, out)| {
+        Ok(
+          Some([rpc_point(&out.key)?, rpc_point(&out.mask)?])
+            .filter(|_| Timelock::Block(height) >= txs[i].prefix.timelock),
+        )
+      })
+      .collect()
+  }
+
+  /// Get the currently estimated fee from the node. This may be manipulated to unsafe levels and
+  /// MUST be sanity checked.
+  // TODO: Take a sanity check argument
+  pub async fn get_fee(&self) -> Result<Fee, RpcError> {
+    #[allow(dead_code)]
+    #[derive(Deserialize, Debug)]
+    struct FeeResponse {
+      fee: u64,
+      quantization_mask: u64,
+    }
+
+    let res: FeeResponse = self.json_rpc_call("get_fee_estimate", None).await?;
+    Ok(Fee { per_weight: res.fee, mask: res.quantization_mask })
+  }
+
+  pub async fn publish_transaction(&self, tx: &Transaction) -> Result<(), RpcError> {
+    #[allow(dead_code)]
+    #[derive(Deserialize, Debug)]
+    struct SendRawResponse {
+      status: String,
+      double_spend: bool,
+      fee_too_low: bool,
+      invalid_input: bool,
+      invalid_output: bool,
+      low_mixin: bool,
+      not_relayed: bool,
+      overspend: bool,
+      too_big: bool,
+      too_few_outputs: bool,
+      reason: String,
+    }
+
+    let res: SendRawResponse = self
+      .rpc_call("send_raw_transaction", Some(json!({ "tx_as_hex": hex::encode(tx.serialize()) })))
+      .await?;
+
+    if res.status != "OK" {
+      Err(RpcError::InvalidTransaction(tx.hash()))?;
+    }
+
+    Ok(())
+  }
+
+  pub async fn generate_blocks(&self, address: &str, block_count: usize) -> Result<(), RpcError> {
+    self
+      .rpc_call::<_, EmptyResponse>(
+        "json_rpc",
+        Some(json!({
+          "method": "generateblocks",
+          "params": {
+            "wallet_address": address,
+            "amount_of_blocks": block_count
+          },
+        })),
+      )
+      .await?;
+
+    Ok(())
+  }
+}

coins/monero/src/serialize.rs

@@ -1,14 +1,25 @@
-use std::io;
+use core::fmt::Debug;
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
 
-use curve25519_dalek::{scalar::Scalar, edwards::{EdwardsPoint, CompressedEdwardsY}};
+use curve25519_dalek::{
+  scalar::Scalar,
+  edwards::{EdwardsPoint, CompressedEdwardsY},
+};
 
-pub const VARINT_CONTINUATION_MASK: u8 = 0b1000_0000;
+const VARINT_CONTINUATION_MASK: u8 = 0b1000_0000;
 
-pub fn varint_len(varint: usize) -> usize {
+pub(crate) fn varint_len(varint: usize) -> usize {
   ((usize::try_from(usize::BITS - varint.leading_zeros()).unwrap().saturating_sub(1)) / 7) + 1
 }
 
-pub fn write_varint<W: io::Write>(varint: &u64, w: &mut W) -> io::Result<()> {
+pub(crate) fn write_byte<W: Write>(byte: &u8, w: &mut W) -> io::Result<()> {
+  w.write_all(&[*byte])
+}
+
+pub(crate) fn write_varint<W: Write>(varint: &u64, w: &mut W) -> io::Result<()> {
   let mut varint = *varint;
   while {
     let mut b = u8::try_from(varint & u64::from(!VARINT_CONTINUATION_MASK)).unwrap();
@@ -16,89 +27,130 @@ pub fn write_varint<W: io::Write>(varint: &u64, w: &mut W) -> io::Result<()> {
     if varint != 0 {
       b |= VARINT_CONTINUATION_MASK;
     }
-    w.write_all(&[b])?;
+    write_byte(&b, w)?;
     varint != 0
   } {}
   Ok(())
 }
 
-pub fn write_scalar<W: io::Write>(scalar: &Scalar, w: &mut W) -> io::Result<()> {
+pub(crate) fn write_scalar<W: Write>(scalar: &Scalar, w: &mut W) -> io::Result<()> {
   w.write_all(&scalar.to_bytes())
 }
 
-pub fn write_point<W: io::Write>(point: &EdwardsPoint, w: &mut W) -> io::Result<()> {
+pub(crate) fn write_point<W: Write>(point: &EdwardsPoint, w: &mut W) -> io::Result<()> {
   w.write_all(&point.compress().to_bytes())
 }
 
-pub fn write_raw_vec<
-  T,
-  W: io::Write,
-  F: Fn(&T, &mut W) -> io::Result<()>
->(f: F, values: &[T], w: &mut W) -> io::Result<()> {
+pub(crate) fn write_raw_vec<T, W: Write, F: Fn(&T, &mut W) -> io::Result<()>>(
+  f: F,
+  values: &[T],
+  w: &mut W,
+) -> io::Result<()> {
   for value in values {
     f(value, w)?;
   }
   Ok(())
 }
 
-pub fn write_vec<
-  T,
-  W: io::Write,
-  F: Fn(&T, &mut W) -> io::Result<()>
->(f: F, values: &[T], w: &mut W) -> io::Result<()> {
+pub(crate) fn write_vec<T, W: Write, F: Fn(&T, &mut W) -> io::Result<()>>(
+  f: F,
+  values: &[T],
+  w: &mut W,
+) -> io::Result<()> {
   write_varint(&values.len().try_into().unwrap(), w)?;
-  write_raw_vec(f, &values, w)
+  write_raw_vec(f, values, w)
 }
 
-pub fn read_byte<R: io::Read>(r: &mut R) -> io::Result<u8> {
-  let mut res = [0; 1];
+pub(crate) fn read_bytes<R: Read, const N: usize>(r: &mut R) -> io::Result<[u8; N]> {
+  let mut res = [0; N];
   r.read_exact(&mut res)?;
-  Ok(res[0])
+  Ok(res)
 }
 
-pub fn read_varint<R: io::Read>(r: &mut R) -> io::Result<u64> {
+pub(crate) fn read_byte<R: Read>(r: &mut R) -> io::Result<u8> {
+  Ok(read_bytes::<_, 1>(r)?[0])
+}
+
+pub(crate) fn read_u16<R: Read>(r: &mut R) -> io::Result<u16> {
+  read_bytes(r).map(u16::from_le_bytes)
+}
+
+pub(crate) fn read_u32<R: Read>(r: &mut R) -> io::Result<u32> {
+  read_bytes(r).map(u32::from_le_bytes)
+}
+
+pub(crate) fn read_u64<R: Read>(r: &mut R) -> io::Result<u64> {
+  read_bytes(r).map(u64::from_le_bytes)
+}
+
+pub(crate) fn read_varint<R: Read>(r: &mut R) -> io::Result<u64> {
   let mut bits = 0;
   let mut res = 0;
   while {
     let b = read_byte(r)?;
+    if (bits != 0) && (b == 0) {
+      Err(io::Error::new(io::ErrorKind::Other, "non-canonical varint"))?;
+    }
+    if ((bits + 7) > 64) && (b >= (1 << (64 - bits))) {
+      Err(io::Error::new(io::ErrorKind::Other, "varint overflow"))?;
+    }
+
     res += u64::from(b & (!VARINT_CONTINUATION_MASK)) << bits;
-    // TODO: Error if bits exceed u64
     bits += 7;
     b & VARINT_CONTINUATION_MASK == VARINT_CONTINUATION_MASK
   } {}
   Ok(res)
 }
 
-pub fn read_32<R: io::Read>(r: &mut R) -> io::Result<[u8; 32]> {
-  let mut res = [0; 32];
-  r.read_exact(&mut res)?;
-  Ok(res)
+// All scalar fields supported by monero-serai are checked to be canonical for valid transactions
+// While from_bytes_mod_order would be more flexible, it's not currently needed and would be
+// inaccurate to include now. While casting a wide net may be preferable, it'd also be inaccurate
+// for now. There's also further edge cases as noted by
+// https://github.com/monero-project/monero/issues/8438, where some scalars had an archaic
+// reduction applied
+pub(crate) fn read_scalar<R: Read>(r: &mut R) -> io::Result<Scalar> {
+  Scalar::from_canonical_bytes(read_bytes(r)?)
+    .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "unreduced scalar"))
 }
 
-// TODO: Potentially update to Monero's parsing rules on scalars/points, which should be any arbitrary 32-bytes
-// We may be able to consider such transactions as malformed and accordingly be opinionated in ignoring them
-pub fn read_scalar<R: io::Read>(r: &mut R) -> io::Result<Scalar> {
-  Scalar::from_canonical_bytes(
-    read_32(r)?
-  ).ok_or(io::Error::new(io::ErrorKind::Other, "unreduced scalar"))
+pub(crate) fn read_point<R: Read>(r: &mut R) -> io::Result<EdwardsPoint> {
+  let bytes = read_bytes(r)?;
+  CompressedEdwardsY(bytes)
+    .decompress()
+    // Ban points which are either unreduced or -0
+    .filter(|point| point.compress().to_bytes() == bytes)
+    .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "invalid point"))
 }
 
-pub fn read_point<R: io::Read>(r: &mut R) -> io::Result<EdwardsPoint> {
-  CompressedEdwardsY(
-    read_32(r)?
-  ).decompress().filter(|point| point.is_torsion_free()).ok_or(io::Error::new(io::ErrorKind::Other, "invalid point"))
+pub(crate) fn read_torsion_free_point<R: Read>(r: &mut R) -> io::Result<EdwardsPoint> {
+  read_point(r)
+    .ok()
+    .filter(EdwardsPoint::is_torsion_free)
+    .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "invalid point"))
 }
 
-pub fn read_raw_vec<R: io::Read, T, F: Fn(&mut R) -> io::Result<T>>(f: F, len: usize, r: &mut R) -> io::Result<Vec<T>> {
-  let mut res = Vec::with_capacity(
-    len.try_into().map_err(|_| io::Error::new(io::ErrorKind::Other, "length exceeds usize"))?
-  );
+pub(crate) fn read_raw_vec<R: Read, T, F: Fn(&mut R) -> io::Result<T>>(
+  f: F,
+  len: usize,
+  r: &mut R,
+) -> io::Result<Vec<T>> {
+  let mut res = vec![];
   for _ in 0 .. len {
     res.push(f(r)?);
   }
   Ok(res)
 }
 
-pub fn read_vec<R: io::Read, T, F: Fn(&mut R) -> io::Result<T>>(f: F, r: &mut R) -> io::Result<Vec<T>> {
+pub(crate) fn read_array<R: Read, T: Debug, F: Fn(&mut R) -> io::Result<T>, const N: usize>(
+  f: F,
+  r: &mut R,
+) -> io::Result<[T; N]> {
+  read_raw_vec(f, N, r).map(|vec| vec.try_into().unwrap())
+}
+
+pub(crate) fn read_vec<R: Read, T, F: Fn(&mut R) -> io::Result<T>>(
+  f: F,
+  r: &mut R,
+) -> io::Result<Vec<T>> {
   read_raw_vec(f, read_varint(r)?.try_into().unwrap(), r)
 }

coins/monero/src/tests/address.rs

@@ -1,45 +1,176 @@
 use hex_literal::hex;
 
-use crate::wallet::address::{Network, AddressType, Address};
+use rand_core::{RngCore, OsRng};
+
+use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, edwards::CompressedEdwardsY};
+
+use crate::{
+  random_scalar,
+  wallet::address::{Network, AddressType, AddressMeta, MoneroAddress},
+};
 
 const SPEND: [u8; 32] = hex!("f8631661f6ab4e6fda310c797330d86e23a682f20d5bc8cc27b18051191f16d7");
 const VIEW: [u8; 32] = hex!("4a1535063ad1fee2dabbf909d4fd9a873e29541b401f0944754e17c9a41820ce");
 
-const STANDARD: &'static str = "4B33mFPMq6mKi7Eiyd5XuyKRVMGVZz1Rqb9ZTyGApXW5d1aT7UBDZ89ewmnWFkzJ5wPd2SFbn313vCT8a4E2Qf4KQH4pNey";
+const STANDARD: &str =
+  "4B33mFPMq6mKi7Eiyd5XuyKRVMGVZz1Rqb9ZTyGApXW5d1aT7UBDZ89ewmnWFkzJ5wPd2SFbn313vCT8a4E2Qf4KQH4pNey";
 
 const PAYMENT_ID: [u8; 8] = hex!("b8963a57855cf73f");
-const INTEGRATED: &'static str = "4Ljin4CrSNHKi7Eiyd5XuyKRVMGVZz1Rqb9ZTyGApXW5d1aT7UBDZ89ewmnWFkzJ5wPd2SFbn313vCT8a4E2Qf4KbaTH6MnpXSn88oBX35";
+const INTEGRATED: &str =
+  "4Ljin4CrSNHKi7Eiyd5XuyKRVMGVZz1Rqb9ZTyGApXW5d1aT7UBDZ89ewmnWFkzJ5wPd2SFbn313vCT8a4E2Qf4KbaTH6Mn\
+  pXSn88oBX35";
 
-const SUB_SPEND: [u8; 32] = hex!("fe358188b528335ad1cfdc24a22a23988d742c882b6f19a602892eaab3c1b62b");
+const SUB_SPEND: [u8; 32] =
+  hex!("fe358188b528335ad1cfdc24a22a23988d742c882b6f19a602892eaab3c1b62b");
 const SUB_VIEW: [u8; 32] = hex!("9bc2b464de90d058468522098d5610c5019c45fd1711a9517db1eea7794f5470");
-const SUBADDRESS: &'static str = "8C5zHM5ud8nGC4hC2ULiBLSWx9infi8JUUmWEat4fcTf8J4H38iWYVdFmPCA9UmfLTZxD43RsyKnGEdZkoGij6csDeUnbEB";
+const SUBADDRESS: &str =
+  "8C5zHM5ud8nGC4hC2ULiBLSWx9infi8JUUmWEat4fcTf8J4H38iWYVdFmPCA9UmfLTZxD43RsyKnGEdZkoGij6csDeUnbEB";
+
+const FEATURED_JSON: &str = include_str!("vectors/featured_addresses.json");
 
 #[test]
 fn standard_address() {
-  let addr = Address::from_str(STANDARD, Network::Mainnet).unwrap();
+  let addr = MoneroAddress::from_str(Network::Mainnet, STANDARD).unwrap();
   assert_eq!(addr.meta.network, Network::Mainnet);
   assert_eq!(addr.meta.kind, AddressType::Standard);
-  assert_eq!(addr.meta.guaranteed, false);
+  assert!(!addr.meta.kind.is_subaddress());
+  assert_eq!(addr.meta.kind.payment_id(), None);
+  assert!(!addr.meta.kind.is_guaranteed());
   assert_eq!(addr.spend.compress().to_bytes(), SPEND);
   assert_eq!(addr.view.compress().to_bytes(), VIEW);
+  assert_eq!(addr.to_string(), STANDARD);
 }
 
 #[test]
 fn integrated_address() {
-  let addr = Address::from_str(INTEGRATED, Network::Mainnet).unwrap();
+  let addr = MoneroAddress::from_str(Network::Mainnet, INTEGRATED).unwrap();
   assert_eq!(addr.meta.network, Network::Mainnet);
   assert_eq!(addr.meta.kind, AddressType::Integrated(PAYMENT_ID));
-  assert_eq!(addr.meta.guaranteed, false);
+  assert!(!addr.meta.kind.is_subaddress());
+  assert_eq!(addr.meta.kind.payment_id(), Some(PAYMENT_ID));
+  assert!(!addr.meta.kind.is_guaranteed());
   assert_eq!(addr.spend.compress().to_bytes(), SPEND);
   assert_eq!(addr.view.compress().to_bytes(), VIEW);
+  assert_eq!(addr.to_string(), INTEGRATED);
 }
 
 #[test]
 fn subaddress() {
-  let addr = Address::from_str(SUBADDRESS, Network::Mainnet).unwrap();
+  let addr = MoneroAddress::from_str(Network::Mainnet, SUBADDRESS).unwrap();
   assert_eq!(addr.meta.network, Network::Mainnet);
   assert_eq!(addr.meta.kind, AddressType::Subaddress);
-  assert_eq!(addr.meta.guaranteed, false);
+  assert!(addr.meta.kind.is_subaddress());
+  assert_eq!(addr.meta.kind.payment_id(), None);
+  assert!(!addr.meta.kind.is_guaranteed());
   assert_eq!(addr.spend.compress().to_bytes(), SUB_SPEND);
   assert_eq!(addr.view.compress().to_bytes(), SUB_VIEW);
+  assert_eq!(addr.to_string(), SUBADDRESS);
+}
+
+#[test]
+fn featured() {
+  for (network, first) in
+    [(Network::Mainnet, 'C'), (Network::Testnet, 'K'), (Network::Stagenet, 'F')]
+  {
+    for _ in 0 .. 100 {
+      let spend = &random_scalar(&mut OsRng) * &ED25519_BASEPOINT_TABLE;
+      let view = &random_scalar(&mut OsRng) * &ED25519_BASEPOINT_TABLE;
+
+      for features in 0 .. (1 << 3) {
+        const SUBADDRESS_FEATURE_BIT: u8 = 1;
+        const INTEGRATED_FEATURE_BIT: u8 = 1 << 1;
+        const GUARANTEED_FEATURE_BIT: u8 = 1 << 2;
+
+        let subaddress = (features & SUBADDRESS_FEATURE_BIT) == SUBADDRESS_FEATURE_BIT;
+
+        let mut payment_id = [0; 8];
+        OsRng.fill_bytes(&mut payment_id);
+        let payment_id = Some(payment_id)
+          .filter(|_| (features & INTEGRATED_FEATURE_BIT) == INTEGRATED_FEATURE_BIT);
+
+        let guaranteed = (features & GUARANTEED_FEATURE_BIT) == GUARANTEED_FEATURE_BIT;
+
+        let kind = AddressType::Featured { subaddress, payment_id, guaranteed };
+        let meta = AddressMeta::new(network, kind);
+        let addr = MoneroAddress::new(meta, spend, view);
+
+        assert_eq!(addr.to_string().chars().next().unwrap(), first);
+        assert_eq!(MoneroAddress::from_str(network, &addr.to_string()).unwrap(), addr);
+
+        assert_eq!(addr.spend, spend);
+        assert_eq!(addr.view, view);
+
+        assert_eq!(addr.is_subaddress(), subaddress);
+        assert_eq!(addr.payment_id(), payment_id);
+        assert_eq!(addr.is_guaranteed(), guaranteed);
+      }
+    }
+  }
+}
+
+#[test]
+fn featured_vectors() {
+  #[derive(serde::Deserialize)]
+  struct Vector {
+    address: String,
+
+    network: String,
+    spend: String,
+    view: String,
+
+    subaddress: bool,
+    integrated: bool,
+    payment_id: Option<[u8; 8]>,
+    guaranteed: bool,
+  }
+
+  let vectors = serde_json::from_str::<Vec<Vector>>(FEATURED_JSON).unwrap();
+  for vector in vectors {
+    let first = vector.address.chars().next().unwrap();
+    let network = match vector.network.as_str() {
+      "Mainnet" => {
+        assert_eq!(first, 'C');
+        Network::Mainnet
+      }
+      "Testnet" => {
+        assert_eq!(first, 'K');
+        Network::Testnet
+      }
+      "Stagenet" => {
+        assert_eq!(first, 'F');
+        Network::Stagenet
+      }
+      _ => panic!("Unknown network"),
+    };
+    let spend =
+      CompressedEdwardsY::from_slice(&hex::decode(vector.spend).unwrap()).decompress().unwrap();
+    let view =
+      CompressedEdwardsY::from_slice(&hex::decode(vector.view).unwrap()).decompress().unwrap();
+
+    let addr = MoneroAddress::from_str(network, &vector.address).unwrap();
+    assert_eq!(addr.spend, spend);
+    assert_eq!(addr.view, view);
+
+    assert_eq!(addr.is_subaddress(), vector.subaddress);
+    assert_eq!(vector.integrated, vector.payment_id.is_some());
+    assert_eq!(addr.payment_id(), vector.payment_id);
+    assert_eq!(addr.is_guaranteed(), vector.guaranteed);
+
+    assert_eq!(
+      MoneroAddress::new(
+        AddressMeta::new(
+          network,
+          AddressType::Featured {
+            subaddress: vector.subaddress,
+            payment_id: vector.payment_id,
+            guaranteed: vector.guaranteed
+          }
+        ),
+        spend,
+        view
+      )
+      .to_string(),
+      vector.address
+    );
+  }
 }

coins/monero/src/tests/bulletproofs.rs

@@ -0,0 +1,92 @@
+use hex_literal::hex;
+use rand_core::OsRng;
+
+use curve25519_dalek::{scalar::Scalar, edwards::CompressedEdwardsY};
+use multiexp::BatchVerifier;
+
+use crate::{
+  Commitment, random_scalar,
+  ringct::bulletproofs::{Bulletproofs, original::OriginalStruct},
+};
+
+#[test]
+fn bulletproofs_vector() {
+  let scalar = |scalar| Scalar::from_canonical_bytes(scalar).unwrap();
+  let point = |point| CompressedEdwardsY(point).decompress().unwrap();
+
+  // Generated from Monero
+  assert!(Bulletproofs::Original(OriginalStruct {
+    A: point(hex!("ef32c0b9551b804decdcb107eb22aa715b7ce259bf3c5cac20e24dfa6b28ac71")),
+    S: point(hex!("e1285960861783574ee2b689ae53622834eb0b035d6943103f960cd23e063fa0")),
+    T1: point(hex!("4ea07735f184ba159d0e0eb662bac8cde3eb7d39f31e567b0fbda3aa23fe5620")),
+    T2: point(hex!("b8390aa4b60b255630d40e592f55ec6b7ab5e3a96bfcdcd6f1cd1d2fc95f441e")),
+    taux: scalar(hex!("5957dba8ea9afb23d6e81cc048a92f2d502c10c749dc1b2bd148ae8d41ec7107")),
+    mu: scalar(hex!("923023b234c2e64774b820b4961f7181f6c1dc152c438643e5a25b0bf271bc02")),
+    L: vec![
+      point(hex!("c45f656316b9ebf9d357fb6a9f85b5f09e0b991dd50a6e0ae9b02de3946c9d99")),
+      point(hex!("9304d2bf0f27183a2acc58cc755a0348da11bd345485fda41b872fee89e72aac")),
+      point(hex!("1bb8b71925d155dd9569f64129ea049d6149fdc4e7a42a86d9478801d922129b")),
+      point(hex!("5756a7bf887aa72b9a952f92f47182122e7b19d89e5dd434c747492b00e1c6b7")),
+      point(hex!("6e497c910d102592830555356af5ff8340e8d141e3fb60ea24cfa587e964f07d")),
+      point(hex!("f4fa3898e7b08e039183d444f3d55040f3c790ed806cb314de49f3068bdbb218")),
+      point(hex!("0bbc37597c3ead517a3841e159c8b7b79a5ceaee24b2a9a20350127aab428713")),
+    ],
+    R: vec![
+      point(hex!("609420ba1702781692e84accfd225adb3d077aedc3cf8125563400466b52dbd9")),
+      point(hex!("fb4e1d079e7a2b0ec14f7e2a3943bf50b6d60bc346a54fcf562fb234b342abf8")),
+      point(hex!("6ae3ac97289c48ce95b9c557289e82a34932055f7f5e32720139824fe81b12e5")),
+      point(hex!("d071cc2ffbdab2d840326ad15f68c01da6482271cae3cf644670d1632f29a15c")),
+      point(hex!("e52a1754b95e1060589ba7ce0c43d0060820ebfc0d49dc52884bc3c65ad18af5")),
+      point(hex!("41573b06140108539957df71aceb4b1816d2409ce896659aa5c86f037ca5e851")),
+      point(hex!("a65970b2cc3c7b08b2b5b739dbc8e71e646783c41c625e2a5b1535e3d2e0f742")),
+    ],
+    a: scalar(hex!("0077c5383dea44d3cd1bc74849376bd60679612dc4b945255822457fa0c0a209")),
+    b: scalar(hex!("fe80cf5756473482581e1d38644007793ddc66fdeb9404ec1689a907e4863302")),
+    t: scalar(hex!("40dfb08e09249040df997851db311bd6827c26e87d6f0f332c55be8eef10e603"))
+  })
+  .verify(
+    &mut OsRng,
+    &[
+      // For some reason, these vectors are * INV_EIGHT
+      point(hex!("8e8f23f315edae4f6c2f948d9a861e0ae32d356b933cd11d2f0e031ac744c41f"))
+        .mul_by_cofactor(),
+      point(hex!("2829cbd025aa54cd6e1b59a032564f22f0b2e5627f7f2c4297f90da438b5510f"))
+        .mul_by_cofactor(),
+    ]
+  ));
+}
+
+macro_rules! bulletproofs_tests {
+  ($name: ident, $max: ident, $plus: literal) => {
+    #[test]
+    fn $name() {
+      // Create Bulletproofs for all possible output quantities
+      let mut verifier = BatchVerifier::new(16);
+      for i in 1 .. 17 {
+        let commitments = (1 ..= i)
+          .map(|i| Commitment::new(random_scalar(&mut OsRng), u64::try_from(i).unwrap()))
+          .collect::<Vec<_>>();
+
+        let bp = Bulletproofs::prove(&mut OsRng, &commitments, $plus).unwrap();
+
+        let commitments = commitments.iter().map(Commitment::calculate).collect::<Vec<_>>();
+        assert!(bp.verify(&mut OsRng, &commitments));
+        assert!(bp.batch_verify(&mut OsRng, &mut verifier, i, &commitments));
+      }
+      assert!(verifier.verify_vartime());
+    }
+
+    #[test]
+    fn $max() {
+      // Check Bulletproofs errors if we try to prove for too many outputs
+      let mut commitments = vec![];
+      for _ in 0 .. 17 {
+        commitments.push(Commitment::new(Scalar::zero(), 0));
+      }
+      assert!(Bulletproofs::prove(&mut OsRng, &commitments, $plus).is_err());
+    }
+  };
+}
+
+bulletproofs_tests!(bulletproofs, bulletproofs_max, false);
+bulletproofs_tests!(bulletproofs_plus, bulletproofs_plus_max, true);

coins/monero/src/tests/clsag.rs

@@ -1,7 +1,11 @@
+use core::ops::Deref;
 #[cfg(feature = "multisig")]
-use std::sync::{Arc, RwLock};
+use std_shims::sync::Arc;
+#[cfg(feature = "multisig")]
+use std::sync::RwLock;
 
-use rand::{RngCore, rngs::OsRng};
+use zeroize::Zeroizing;
+use rand_core::{RngCore, OsRng};
 
 use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, scalar::Scalar};
 
@@ -11,16 +15,21 @@ use transcript::{Transcript, RecommendedTranscript};
 use frost::curve::Ed25519;
 
 use crate::{
-  Commitment,
-  random_scalar,
+  Commitment, random_scalar,
   wallet::Decoys,
-  ringct::{generate_key_image, clsag::{ClsagInput, Clsag}}
+  ringct::{
+    generate_key_image,
+    clsag::{ClsagInput, Clsag},
+  },
 };
 #[cfg(feature = "multisig")]
-use crate::{frost::MultisigError, ringct::clsag::{ClsagDetails, ClsagMultisig}};
+use crate::ringct::clsag::{ClsagDetails, ClsagMultisig};
 
 #[cfg(feature = "multisig")]
-use frost::tests::{key_gen, algorithm_machines, sign};
+use frost::{
+  Participant,
+  tests::{key_gen, algorithm_machines, sign},
+};
 
 const RING_LEN: u64 = 11;
 const AMOUNT: u64 = 1337;
@@ -33,48 +42,48 @@ fn clsag() {
   for real in 0 .. RING_LEN {
     let msg = [1; 32];
 
-    let mut secrets = [Scalar::zero(), Scalar::zero()];
+    let mut secrets = (Zeroizing::new(Scalar::zero()), Scalar::zero());
     let mut ring = vec![];
     for i in 0 .. RING_LEN {
-      let dest = random_scalar(&mut OsRng);
+      let dest = Zeroizing::new(random_scalar(&mut OsRng));
       let mask = random_scalar(&mut OsRng);
-      let amount;
-      if i == u64::from(real) {
-        secrets = [dest, mask];
-        amount = AMOUNT;
+      let amount = if i == real {
+        secrets = (dest.clone(), mask);
+        AMOUNT
       } else {
-        amount = OsRng.next_u64();
-      }
-      ring.push([&dest * &ED25519_BASEPOINT_TABLE, Commitment::new(mask, amount).calculate()]);
+        OsRng.next_u64()
+      };
+      ring
+        .push([dest.deref() * &ED25519_BASEPOINT_TABLE, Commitment::new(mask, amount).calculate()]);
     }
 
-    let image = generate_key_image(secrets[0]);
+    let image = generate_key_image(&secrets.0);
     let (clsag, pseudo_out) = Clsag::sign(
       &mut OsRng,
-      &vec![(
-        secrets[0],
+      vec![(
+        secrets.0,
         image,
         ClsagInput::new(
-          Commitment::new(secrets[1], AMOUNT),
+          Commitment::new(secrets.1, AMOUNT),
           Decoys {
             i: u8::try_from(real).unwrap(),
-            offsets: (1 ..= RING_LEN).into_iter().collect(),
-            ring: ring.clone()
-          }
-        ).unwrap()
+            offsets: (1 ..= RING_LEN).collect(),
+            ring: ring.clone(),
+          },
+        )
+        .unwrap(),
       )],
       random_scalar(&mut OsRng),
-      msg
-    ).swap_remove(0);
+      msg,
+    )
+    .swap_remove(0);
     clsag.verify(&ring, &image, &pseudo_out, &msg).unwrap();
-    #[cfg(feature = "experimental")]
-    clsag.rust_verify(&ring, &image, &pseudo_out, &msg).unwrap();
   }
 }
 
 #[cfg(feature = "multisig")]
 #[test]
-fn clsag_multisig() -> Result<(), MultisigError> {
+fn clsag_multisig() {
   let keys = key_gen::<_, Ed25519>(&mut OsRng);
 
   let randomness = random_scalar(&mut OsRng);
@@ -82,45 +91,37 @@ fn clsag_multisig() -> Result<(), MultisigError> {
   for i in 0 .. RING_LEN {
     let dest;
     let mask;
-    let amount;
-    if i != u64::from(RING_INDEX) {
+    let amount = if i == u64::from(RING_INDEX) {
+      dest = keys[&Participant::new(1).unwrap()].group_key().0;
+      mask = randomness;
+      AMOUNT
+    } else {
       dest = &random_scalar(&mut OsRng) * &ED25519_BASEPOINT_TABLE;
       mask = random_scalar(&mut OsRng);
-      amount = OsRng.next_u64();
-    } else {
-      dest = keys[&1].group_key().0;
-      mask = randomness;
-      amount = AMOUNT;
-    }
+      OsRng.next_u64()
+    };
     ring.push([dest, Commitment::new(mask, amount).calculate()]);
   }
 
   let mask_sum = random_scalar(&mut OsRng);
-  sign(
-    &mut OsRng,
-    algorithm_machines(
-      &mut OsRng,
-      ClsagMultisig::new(
-        RecommendedTranscript::new(b"Monero Serai CLSAG Test"),
-        keys[&1].group_key().0,
-        Arc::new(RwLock::new(Some(
-          ClsagDetails::new(
-            ClsagInput::new(
-              Commitment::new(randomness, AMOUNT),
-              Decoys {
-                i: RING_INDEX,
-                offsets: (1 ..= RING_LEN).into_iter().collect(),
-                ring: ring.clone()
-              }
-            ).unwrap(),
-            mask_sum
-          )
-        )))
-      ).unwrap(),
-      &keys
-    ),
-    &[1; 32]
+  let algorithm = ClsagMultisig::new(
+    RecommendedTranscript::new(b"Monero Serai CLSAG Test"),
+    keys[&Participant::new(1).unwrap()].group_key().0,
+    Arc::new(RwLock::new(Some(ClsagDetails::new(
+      ClsagInput::new(
+        Commitment::new(randomness, AMOUNT),
+        Decoys { i: RING_INDEX, offsets: (1 ..= RING_LEN).collect(), ring: ring.clone() },
+      )
+      .unwrap(),
+      mask_sum,
+    )))),
   );
 
-  Ok(())
+  sign(
+    &mut OsRng,
+    algorithm.clone(),
+    keys.clone(),
+    algorithm_machines(&mut OsRng, algorithm, &keys),
+    &[1; 32],
+  );
 }

coins/monero/src/tests/hash_to_point.rs

@@ -1,13 +0,0 @@
-use rand::rngs::OsRng;
-
-use curve25519_dalek::constants::ED25519_BASEPOINT_TABLE;
-
-use crate::{random_scalar, ringct::hash_to_point::{hash_to_point as c_hash_to_point, rust_hash_to_point}};
-
-#[test]
-fn hash_to_point() {
-  for _ in 0 .. 50 {
-    let point = &random_scalar(&mut OsRng) * &ED25519_BASEPOINT_TABLE;
-    assert_eq!(rust_hash_to_point(point), c_hash_to_point(point));
-  }
-}

coins/monero/src/tests/mod.rs

@@ -1,3 +1,4 @@
-mod hash_to_point;
 mod clsag;
+mod bulletproofs;
 mod address;
+mod seed;

coins/monero/src/tests/seed.rs

@@ -0,0 +1,177 @@
+use zeroize::Zeroizing;
+
+use rand_core::OsRng;
+
+use curve25519_dalek::scalar::Scalar;
+
+use crate::{
+  hash,
+  wallet::seed::{Seed, Language, classic::trim_by_lang},
+};
+
+#[test]
+fn test_classic_seed() {
+  struct Vector {
+    language: Language,
+    seed: String,
+    spend: String,
+    view: String,
+  }
+
+  let vectors = [
+    Vector {
+      language: Language::Chinese,
+      seed: "摇 曲 艺 武 滴 然 效 似 赏 式 祥 歌 买 疑 小 碧 堆 博 键 房 鲜 悲 付 喷 武".into(),
+      spend: "a5e4fff1706ef9212993a69f246f5c95ad6d84371692d63e9bb0ea112a58340d".into(),
+      view: "1176c43ce541477ea2f3ef0b49b25112b084e26b8a843e1304ac4677b74cdf02".into(),
+    },
+    Vector {
+      language: Language::English,
+      seed: "washing thirsty occur lectures tuesday fainted toxic adapt \
+               abnormal memoir nylon mostly building shrugged online ember northern \
+               ruby woes dauntless boil family illness inroads northern"
+        .into(),
+      spend: "c0af65c0dd837e666b9d0dfed62745f4df35aed7ea619b2798a709f0fe545403".into(),
+      view: "513ba91c538a5a9069e0094de90e927c0cd147fa10428ce3ac1afd49f63e3b01".into(),
+    },
+    Vector {
+      language: Language::Dutch,
+      seed: "setwinst riphagen vimmetje extase blief tuitelig fuiven meifeest \
+               ponywagen zesmaal ripdeal matverf codetaal leut ivoor rotten \
+               wisgerhof winzucht typograaf atrium rein zilt traktaat verzaagd setwinst"
+        .into(),
+      spend: "e2d2873085c447c2bc7664222ac8f7d240df3aeac137f5ff2022eaa629e5b10a".into(),
+      view: "eac30b69477e3f68093d131c7fd961564458401b07f8c87ff8f6030c1a0c7301".into(),
+    },
+    Vector {
+      language: Language::French,
+      seed: "poids vaseux tarte bazar poivre effet entier nuance \
+               sensuel ennui pacte osselet poudre battre alibi mouton \
+               stade paquet pliage gibier type question position projet pliage"
+        .into(),
+      spend: "2dd39ff1a4628a94b5c2ec3e42fb3dfe15c2b2f010154dc3b3de6791e805b904".into(),
+      view: "6725b32230400a1032f31d622b44c3a227f88258939b14a7c72e00939e7bdf0e".into(),
+    },
+    Vector {
+      language: Language::Spanish,
+      seed: "minero ocupar mirar evadir octubre cal logro miope \
+               opaco disco ancla litio clase cuello nasal clase \
+               fiar avance deseo mente grumo negro cordón croqueta clase"
+        .into(),
+      spend: "ae2c9bebdddac067d73ec0180147fc92bdf9ac7337f1bcafbbe57dd13558eb02".into(),
+      view: "18deafb34d55b7a43cae2c1c1c206a3c80c12cc9d1f84640b484b95b7fec3e05".into(),
+    },
+    Vector {
+      language: Language::German,
+      seed: "Kaliber Gabelung Tapir Liveband Favorit Specht Enklave Nabel \
+               Jupiter Foliant Chronik nisten löten Vase Aussage Rekord \
+               Yeti Gesetz Eleganz Alraune Künstler Almweide Jahr Kastanie Almweide"
+        .into(),
+      spend: "79801b7a1b9796856e2397d862a113862e1fdc289a205e79d8d70995b276db06".into(),
+      view: "99f0ec556643bd9c038a4ed86edcb9c6c16032c4622ed2e000299d527a792701".into(),
+    },
+    Vector {
+      language: Language::Italian,
+      seed: "cavo pancetta auto fulmine alleanza filmato diavolo prato \
+               forzare meritare litigare lezione segreto evasione votare buio \
+               licenza cliente dorso natale crescere vento tutelare vetta evasione"
+        .into(),
+      spend: "5e7fd774eb00fa5877e2a8b4dc9c7ffe111008a3891220b56a6e49ac816d650a".into(),
+      view: "698a1dce6018aef5516e82ca0cb3e3ec7778d17dfb41a137567bfa2e55e63a03".into(),
+    },
+    Vector {
+      language: Language::Portuguese,
+      seed: "agito eventualidade onus itrio holograma sodomizar objetos dobro \
+               iugoslavo bcrepuscular odalisca abjeto iuane darwinista eczema acetona \
+               cibernetico hoquei gleba driver buffer azoto megera nogueira agito"
+        .into(),
+      spend: "13b3115f37e35c6aa1db97428b897e584698670c1b27854568d678e729200c0f".into(),
+      view: "ad1b4fd35270f5f36c4da7166672b347e75c3f4d41346ec2a06d1d0193632801".into(),
+    },
+    Vector {
+      language: Language::Japanese,
+      seed: "ぜんぶ どうぐ おたがい せんきょ おうじ そんちょう じゅしん いろえんぴつ \
+               かほう つかれる えらぶ にちじょう くのう にちようび ぬまえび さんきゃく \
+               おおや ちぬき うすめる いがく せつでん さうな すいえい せつだん おおや"
+        .into(),
+      spend: "c56e895cdb13007eda8399222974cdbab493640663804b93cbef3d8c3df80b0b".into(),
+      view: "6c3634a313ec2ee979d565c33888fd7c3502d696ce0134a8bc1a2698c7f2c508".into(),
+    },
+    Vector {
+      language: Language::Russian,
+      seed: "шатер икра нация ехать получать инерция доза реальный \
+               рыжий таможня лопата душа веселый клетка атлас лекция \
+               обгонять паек наивный лыжный дурак стать ежик задача паек"
+        .into(),
+      spend: "7cb5492df5eb2db4c84af20766391cd3e3662ab1a241c70fc881f3d02c381f05".into(),
+      view: "fcd53e41ec0df995ab43927f7c44bc3359c93523d5009fb3f5ba87431d545a03".into(),
+    },
+    Vector {
+      language: Language::Esperanto,
+      seed: "ukazo klini peco etikedo fabriko imitado onklino urino \
+               pudro incidento kumuluso ikono smirgi hirundo uretro krii \
+               sparkado super speciala pupo alpinisto cvana vokegi zombio fabriko"
+        .into(),
+      spend: "82ebf0336d3b152701964ed41df6b6e9a035e57fc98b84039ed0bd4611c58904".into(),
+      view: "cd4d120e1ea34360af528f6a3e6156063312d9cefc9aa6b5218d366c0ed6a201".into(),
+    },
+    Vector {
+      language: Language::Lojban,
+      seed: "jetnu vensa julne xrotu xamsi julne cutci dakli \
+               mlatu xedja muvgau palpi xindo sfubu ciste cinri \
+               blabi darno dembi janli blabi fenki bukpu burcu blabi"
+        .into(),
+      spend: "e4f8c6819ab6cf792cebb858caabac9307fd646901d72123e0367ebc0a79c200".into(),
+      view: "c806ce62bafaa7b2d597f1a1e2dbe4a2f96bfd804bf6f8420fc7f4a6bd700c00".into(),
+    },
+    Vector {
+      language: Language::EnglishOld,
+      seed: "glorious especially puff son moment add youth nowhere \
+               throw glide grip wrong rhythm consume very swear \
+               bitter heavy eventually begin reason flirt type unable"
+        .into(),
+      spend: "647f4765b66b636ff07170ab6280a9a6804dfbaf19db2ad37d23be024a18730b".into(),
+      view: "045da65316a906a8c30046053119c18020b07a7a3a6ef5c01ab2a8755416bd02".into(),
+    },
+  ];
+
+  for vector in vectors {
+    let trim_seed = |seed: &str| {
+      seed
+        .split_whitespace()
+        .map(|word| trim_by_lang(word, vector.language))
+        .collect::<Vec<_>>()
+        .join(" ")
+    };
+
+    // Test against Monero
+    {
+      let seed = Seed::from_string(Zeroizing::new(vector.seed.clone())).unwrap();
+      assert_eq!(seed, Seed::from_string(Zeroizing::new(trim_seed(&vector.seed))).unwrap());
+
+      let spend: [u8; 32] = hex::decode(vector.spend).unwrap().try_into().unwrap();
+      // For classical seeds, Monero directly uses the entropy as a spend key
+      assert_eq!(
+        Scalar::from_canonical_bytes(*seed.entropy()),
+        Scalar::from_canonical_bytes(spend)
+      );
+
+      let view: [u8; 32] = hex::decode(vector.view).unwrap().try_into().unwrap();
+      // Monero then derives the view key as H(spend)
+      assert_eq!(
+        Scalar::from_bytes_mod_order(hash(&spend)),
+        Scalar::from_canonical_bytes(view).unwrap()
+      );
+
+      assert_eq!(Seed::from_entropy(vector.language, Zeroizing::new(spend)).unwrap(), seed);
+    }
+
+    // Test against ourself
+    {
+      let seed = Seed::new(&mut OsRng, vector.language);
+      assert_eq!(seed, Seed::from_string(Zeroizing::new(trim_seed(&seed.to_string()))).unwrap());
+      assert_eq!(seed, Seed::from_entropy(vector.language, seed.entropy()).unwrap());
+      assert_eq!(seed, Seed::from_string(seed.to_string()).unwrap());
+    }
+  }
+}

coins/monero/src/tests/vectors/featured_addresses.json

@@ -0,0 +1,230 @@
+[
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5Jye2v3pYyUDn",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": false,
+    "integrated": false,
+    "guaranteed": false
+  },
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5Jye2v3wfMHCy",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": true,
+    "integrated": false,
+    "guaranteed": false
+  },
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5JyeeJTo4p5ayvj36PStM5AX",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": false,
+    "integrated": true,
+    "payment_id": [46, 48, 134, 34, 245, 148, 243, 195],
+    "guaranteed": false
+  },
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5JyeeJWv5WqMCNE2hRs9rJfy",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": true,
+    "integrated": true,
+    "payment_id": [153, 176, 98, 204, 151, 27, 197, 168],
+    "guaranteed": false
+  },
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5Jye2v4DwqwH1",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": false,
+    "integrated": false,
+    "guaranteed": true
+  },
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5Jye2v4Pyz8bD",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": true,
+    "integrated": false,
+    "guaranteed": true
+  },
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5JyeeJcwt7hykou237MqZZDA",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": false,
+    "integrated": true,
+    "payment_id": [88, 37, 149, 111, 171, 108, 120, 181],
+    "guaranteed": true
+  },
+  {
+    "address": "CjWdTpuDaZ69nTGxzm9YarR82YDYFECi1WaaREZTMy5yDsjaRX5bC3cbC3JpcrBPd7YYpjoWKuBMidgGaKBK5JyeeJfTrFAp69u2MYbf5YeN",
+    "network": "Mainnet",
+    "spend": "258dfe7eef9be934839f3b8e0d40e79035fe85879c0a9eb0d7372ae2deb0004c",
+    "view": "f91382373045f3cc69233254ab0406bc9e008707569ff9db4718654812d839df",
+    "subaddress": true,
+    "integrated": true,
+    "payment_id": [125, 69, 155, 152, 140, 160, 157, 186],
+    "guaranteed": true
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x712U9w7ScYA",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": false,
+    "integrated": false,
+    "guaranteed": false
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x712UA2gCrT1",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": true,
+    "integrated": false,
+    "guaranteed": false
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x71Vc1DbPKwJu81cxJjqBkS",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": false,
+    "integrated": true,
+    "payment_id": [92, 225, 118, 220, 39, 3, 72, 51],
+    "guaranteed": false
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x71Vc2o1rPMaXN31Fe5J6dn",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": true,
+    "integrated": true,
+    "payment_id": [20, 120, 47, 89, 72, 165, 233, 115],
+    "guaranteed": false
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x712UAQHCRZ4",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": false,
+    "integrated": false,
+    "guaranteed": true
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x712UAUzqaii",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": true,
+    "integrated": false,
+    "guaranteed": true
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x71VcAsfQc3gJQ2gHLd5DiQ",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": false,
+    "integrated": true,
+    "payment_id": [193, 149, 123, 214, 180, 205, 195, 91],
+    "guaranteed": true
+  },
+  {
+    "address": "Kgx5uCVsMSEVm7seL8tjyRGmmVXjWfEowKpKjgaXUGVyMViBYMh13VQ4mfqpB7zEVVcJx3E8FFgAuQ8cq6mg5x71VcDBAD5jbZQ3AMHFyvQB",
+    "network": "Testnet",
+    "spend": "bba3a8a5bb47f7abf2e2dffeaf43385e4b308fd63a9ff6707e355f3b0a6c247a",
+    "view": "881713a4fa9777168a54bbdcb75290d319fb92fdf1026a8a4b125a8e341de8ab",
+    "subaddress": true,
+    "integrated": true,
+    "payment_id": [205, 170, 65, 0, 51, 175, 251, 184],
+    "guaranteed": true
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV61VPJnBtTP",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": false,
+    "integrated": false,
+    "guaranteed": false
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV61VPUrwMvP",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": true,
+    "integrated": false,
+    "guaranteed": false
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV6AY5ECEhP5Nr1aCRPXdxk",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": false,
+    "integrated": true,
+    "payment_id": [173, 149, 78, 64, 215, 211, 66, 170],
+    "guaranteed": false
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV6AY882kTUS1D2LttnPvTR",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": true,
+    "integrated": true,
+    "payment_id": [254, 159, 186, 162, 1, 8, 156, 108],
+    "guaranteed": false
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV61VPpBBo8F",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": false,
+    "integrated": false,
+    "guaranteed": true
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV61VPuUJX3b",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": true,
+    "integrated": false,
+    "guaranteed": true
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV6AYCZPxVAoDu21DryMoto",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": false,
+    "integrated": true,
+    "payment_id": [3, 115, 230, 129, 172, 108, 116, 235],
+    "guaranteed": true
+  },
+  {
+    "address": "FSDinqdKK54PbjF73GgW3nUpf7bF8QbyxFCUurENmUyeEfSxSLL2hxwANBLzq1A8gTSAzzEn65hKjetA8o5BvjV6AYFYCqKQAWL18KkpBQ8R",
+    "network": "Stagenet",
+    "spend": "4cd503040f5e43871bf37d8ca7177da655bda410859af754e24e7b44437f3151",
+    "view": "af60d42b6c6e4437fd93eb32657a14967efa393630d7aee27b5973c8e1c5ad39",
+    "subaddress": true,
+    "integrated": true,
+    "payment_id": [94, 122, 63, 167, 209, 225, 14, 180],
+    "guaranteed": true
+  }
+]

coins/monero/src/transaction.rs

@@ -1,69 +1,83 @@
 use core::cmp::Ordering;
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
 
-use curve25519_dalek::edwards::EdwardsPoint;
+use zeroize::Zeroize;
 
-use crate::{hash, serialize::*, ringct::{RctPrunable, RctSignatures}};
+use curve25519_dalek::{
+  scalar::Scalar,
+  edwards::{EdwardsPoint, CompressedEdwardsY},
+};
 
-pub const RING_LEN: usize = 11;
+use crate::{
+  Protocol, hash,
+  serialize::*,
+  ringct::{RctBase, RctPrunable, RctSignatures},
+};
 
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub enum Input {
   Gen(u64),
-
-  ToKey {
-    amount: u64,
-    key_offsets: Vec<u64>,
-    key_image: EdwardsPoint
-  }
+  ToKey { amount: Option<u64>, key_offsets: Vec<u64>, key_image: EdwardsPoint },
 }
 
 impl Input {
   // Worst-case predictive len
-  pub(crate) fn fee_weight() -> usize {
+  pub(crate) fn fee_weight(ring_len: usize) -> usize {
     // Uses 1 byte for the VarInt amount due to amount being 0
     // Uses 1 byte for the VarInt encoding of the length of the ring as well
-    1 + 1 + 1 + (8 * RING_LEN) + 32
+    1 + 1 + 1 + (8 * ring_len) + 32
   }
 
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
     match self {
-      Input::Gen(height) => {
+      Self::Gen(height) => {
         w.write_all(&[255])?;
         write_varint(height, w)
-      },
+      }
 
-      Input::ToKey { amount, key_offsets, key_image } => {
+      Self::ToKey { amount, key_offsets, key_image } => {
         w.write_all(&[2])?;
-        write_varint(amount, w)?;
+        write_varint(&amount.unwrap_or(0), w)?;
         write_vec(write_varint, key_offsets, w)?;
         write_point(key_image, w)
       }
     }
   }
 
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<Input> {
-    let mut variant = [0];
-    r.read_exact(&mut variant)?;
-    Ok(
-      match variant[0] {
-        255 => Input::Gen(read_varint(r)?),
-        2 => Input::ToKey {
-          amount: read_varint(r)?,
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut res = vec![];
+    self.write(&mut res).unwrap();
+    res
+  }
+
+  pub fn read<R: Read>(interpret_as_rct: bool, r: &mut R) -> io::Result<Self> {
+    Ok(match read_byte(r)? {
+      255 => Self::Gen(read_varint(r)?),
+      2 => {
+        let amount = read_varint(r)?;
+        let amount = if (amount == 0) && interpret_as_rct { None } else { Some(amount) };
+        Self::ToKey {
+          amount,
           key_offsets: read_vec(read_varint, r)?,
-          key_image: read_point(r)?
-        },
-        _ => Err(std::io::Error::new(std::io::ErrorKind::Other, "Tried to deserialize unknown/unused input type"))?
+          key_image: read_torsion_free_point(r)?,
+        }
       }
-    )
+      _ => {
+        Err(io::Error::new(io::ErrorKind::Other, "Tried to deserialize unknown/unused input type"))?
+      }
+    })
   }
 }
 
 // Doesn't bother moving to an enum for the unused Script classes
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct Output {
-  pub amount: u64,
-  pub key: EdwardsPoint,
-  pub tag: Option<u8>
+  pub amount: Option<u64>,
+  pub key: CompressedEdwardsY,
+  pub view_tag: Option<u8>,
 }
 
 impl Output {
@@ -71,64 +85,76 @@ impl Output {
     1 + 1 + 32 + 1
   }
 
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
-    write_varint(&self.amount, w)?;
-    w.write_all(&[2 + (if self.tag.is_some() { 1 } else { 0 })])?;
-    write_point(&self.key, w)?;
-    if let Some(tag) = self.tag {
-      w.write_all(&[tag])?;
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    write_varint(&self.amount.unwrap_or(0), w)?;
+    w.write_all(&[2 + u8::from(self.view_tag.is_some())])?;
+    w.write_all(&self.key.to_bytes())?;
+    if let Some(view_tag) = self.view_tag {
+      w.write_all(&[view_tag])?;
     }
     Ok(())
   }
 
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<Output> {
-    let amount = read_varint(r)?;
-    let mut tag = [0];
-    r.read_exact(&mut tag)?;
-    if (tag[0] != 2) && (tag[0] != 3) {
-      Err(std::io::Error::new(std::io::ErrorKind::Other, "Tried to deserialize unknown/unused output type"))?;
-    }
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut res = Vec::with_capacity(8 + 1 + 32);
+    self.write(&mut res).unwrap();
+    res
+  }
 
-    Ok(
-      Output {
-        amount,
-        key: read_point(r)?,
-        tag: if tag[0] == 3 { r.read_exact(&mut tag)?; Some(tag[0]) } else { None }
+  pub fn read<R: Read>(interpret_as_rct: bool, r: &mut R) -> io::Result<Self> {
+    let amount = read_varint(r)?;
+    let amount = if interpret_as_rct {
+      if amount != 0 {
+        Err(io::Error::new(io::ErrorKind::Other, "RCT TX output wasn't 0"))?;
       }
-    )
+      None
+    } else {
+      Some(amount)
+    };
+
+    let view_tag = match read_byte(r)? {
+      2 => false,
+      3 => true,
+      _ => Err(io::Error::new(
+        io::ErrorKind::Other,
+        "Tried to deserialize unknown/unused output type",
+      ))?,
+    };
+
+    Ok(Self {
+      amount,
+      key: CompressedEdwardsY(read_bytes(r)?),
+      view_tag: if view_tag { Some(read_byte(r)?) } else { None },
+    })
   }
 }
 
-#[derive(Clone, Copy, PartialEq, Debug)]
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
 pub enum Timelock {
   None,
   Block(usize),
-  Time(u64)
+  Time(u64),
 }
 
 impl Timelock {
-  fn from_raw(raw: u64) -> Timelock {
+  fn from_raw(raw: u64) -> Self {
     if raw == 0 {
-      Timelock::None
+      Self::None
     } else if raw < 500_000_000 {
-      Timelock::Block(usize::try_from(raw).unwrap())
+      Self::Block(usize::try_from(raw).unwrap())
     } else {
-      Timelock::Time(raw)
+      Self::Time(raw)
     }
   }
 
-  pub(crate) fn fee_weight() -> usize {
-    8
-  }
-
-  fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
+  fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
     write_varint(
       &match self {
-        Timelock::None => 0,
-        Timelock::Block(block) => (*block).try_into().unwrap(),
-        Timelock::Time(time) => *time
+        Self::None => 0,
+        Self::Block(block) => (*block).try_into().unwrap(),
+        Self::Time(time) => *time,
       },
-      w
+      w,
     )
   }
 }
@@ -136,138 +162,216 @@ impl Timelock {
 impl PartialOrd for Timelock {
   fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
     match (self, other) {
-      (Timelock::None, _) => Some(Ordering::Less),
-      (Timelock::Block(a), Timelock::Block(b)) => a.partial_cmp(b),
-      (Timelock::Time(a), Timelock::Time(b)) => a.partial_cmp(b),
-      _ => None
+      (Self::None, _) => Some(Ordering::Less),
+      (Self::Block(a), Self::Block(b)) => a.partial_cmp(b),
+      (Self::Time(a), Self::Time(b)) => a.partial_cmp(b),
+      _ => None,
     }
   }
 }
 
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct TransactionPrefix {
   pub version: u64,
   pub timelock: Timelock,
   pub inputs: Vec<Input>,
   pub outputs: Vec<Output>,
-  pub extra: Vec<u8>
+  pub extra: Vec<u8>,
 }
 
 impl TransactionPrefix {
-  pub(crate) fn fee_weight(inputs: usize, outputs: usize, extra: usize) -> usize {
+  pub(crate) fn fee_weight(ring_len: usize, inputs: usize, outputs: usize, extra: usize) -> usize {
     // Assumes Timelock::None since this library won't let you create a TX with a timelock
     1 + 1 +
-    varint_len(inputs) + (inputs * Input::fee_weight()) +
-    // Only 16 outputs are possible under transactions by this lib
-    1 + (outputs * Output::fee_weight()) +
-    varint_len(extra) + extra
+      varint_len(inputs) +
+      (inputs * Input::fee_weight(ring_len)) +
+      1 +
+      (outputs * Output::fee_weight()) +
+      varint_len(extra) +
+      extra
   }
 
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
     write_varint(&self.version, w)?;
-    self.timelock.serialize(w)?;
-    write_vec(Input::serialize, &self.inputs, w)?;
-    write_vec(Output::serialize, &self.outputs, w)?;
+    self.timelock.write(w)?;
+    write_vec(Input::write, &self.inputs, w)?;
+    write_vec(Output::write, &self.outputs, w)?;
     write_varint(&self.extra.len().try_into().unwrap(), w)?;
     w.write_all(&self.extra)
   }
 
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<TransactionPrefix> {
-    let mut prefix = TransactionPrefix {
-      version: read_varint(r)?,
-      timelock: Timelock::from_raw(read_varint(r)?),
-      inputs: read_vec(Input::deserialize, r)?,
-      outputs: read_vec(Output::deserialize, r)?,
-      extra: vec![]
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut res = vec![];
+    self.write(&mut res).unwrap();
+    res
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    let version = read_varint(r)?;
+    // TODO: Create an enum out of version
+    if (version == 0) || (version > 2) {
+      Err(io::Error::new(io::ErrorKind::Other, "unrecognized transaction version"))?;
+    }
+
+    let timelock = Timelock::from_raw(read_varint(r)?);
+
+    let inputs = read_vec(|r| Input::read(version == 2, r), r)?;
+    if inputs.is_empty() {
+      Err(io::Error::new(io::ErrorKind::Other, "transaction had no inputs"))?;
+    }
+    let is_miner_tx = matches!(inputs[0], Input::Gen { .. });
+
+    let mut prefix = Self {
+      version,
+      timelock,
+      inputs,
+      outputs: read_vec(|r| Output::read((!is_miner_tx) && (version == 2), r), r)?,
+      extra: vec![],
     };
-
-    let len = read_varint(r)?;
-    prefix.extra.resize(len.try_into().unwrap(), 0);
-    r.read_exact(&mut prefix.extra)?;
-
+    prefix.extra = read_vec(read_byte, r)?;
     Ok(prefix)
   }
-}
-
-#[derive(Clone, PartialEq, Debug)]
-pub struct Transaction {
-  pub prefix: TransactionPrefix,
-  pub rct_signatures: RctSignatures
-}
-
-impl Transaction {
-  pub(crate) fn fee_weight(inputs: usize, outputs: usize, extra: usize) -> usize {
-    TransactionPrefix::fee_weight(inputs, outputs, extra) + RctSignatures::fee_weight(inputs, outputs)
-  }
-
-  pub fn serialize<W: std::io::Write>(&self, w: &mut W) -> std::io::Result<()> {
-    self.prefix.serialize(w)?;
-    self.rct_signatures.serialize(w)
-  }
-
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<Transaction> {
-    let prefix = TransactionPrefix::deserialize(r)?;
-    Ok(
-      Transaction {
-        rct_signatures: RctSignatures::deserialize(
-          prefix.inputs.iter().map(|input| match input {
-            Input::Gen(_) => 0,
-            Input::ToKey { key_offsets, .. } => key_offsets.len()
-          }).collect(),
-          prefix.outputs.len(),
-          r
-        )?,
-        prefix
-      }
-    )
-  }
 
   pub fn hash(&self) -> [u8; 32] {
-    let mut serialized = Vec::with_capacity(2048);
+    hash(&self.serialize())
+  }
+}
+
+/// Monero transaction. For version 1, rct_signatures still contains an accurate fee value.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct Transaction {
+  pub prefix: TransactionPrefix,
+  pub signatures: Vec<Vec<(Scalar, Scalar)>>,
+  pub rct_signatures: RctSignatures,
+}
+
+impl Transaction {
+  pub(crate) fn fee_weight(
+    protocol: Protocol,
+    inputs: usize,
+    outputs: usize,
+    extra: usize,
+  ) -> usize {
+    TransactionPrefix::fee_weight(protocol.ring_len(), inputs, outputs, extra) +
+      RctSignatures::fee_weight(protocol, inputs, outputs)
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.prefix.write(w)?;
     if self.prefix.version == 1 {
-      self.serialize(&mut serialized).unwrap();
-      hash(&serialized)
-    } else {
-      let mut sig_hash = Vec::with_capacity(96);
-
-      self.prefix.serialize(&mut serialized).unwrap();
-      sig_hash.extend(hash(&serialized));
-      serialized.clear();
-
-      self.rct_signatures.base.serialize(
-        &mut serialized,
-        self.rct_signatures.prunable.rct_type()
-      ).unwrap();
-      sig_hash.extend(hash(&serialized));
-      serialized.clear();
-
-      match self.rct_signatures.prunable {
-        RctPrunable::Null => serialized.resize(32, 0),
-        _ => {
-          self.rct_signatures.prunable.serialize(&mut serialized).unwrap();
-          serialized = hash(&serialized).to_vec();
+      for sigs in &self.signatures {
+        for sig in sigs {
+          write_scalar(&sig.0, w)?;
+          write_scalar(&sig.1, w)?;
         }
       }
-      sig_hash.extend(&serialized);
-
-      hash(&sig_hash)
+      Ok(())
+    } else if self.prefix.version == 2 {
+      self.rct_signatures.write(w)
+    } else {
+      panic!("Serializing a transaction with an unknown version");
     }
   }
 
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut res = Vec::with_capacity(2048);
+    self.write(&mut res).unwrap();
+    res
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    let prefix = TransactionPrefix::read(r)?;
+    let mut signatures = vec![];
+    let mut rct_signatures = RctSignatures {
+      base: RctBase { fee: 0, encrypted_amounts: vec![], pseudo_outs: vec![], commitments: vec![] },
+      prunable: RctPrunable::Null,
+    };
+
+    if prefix.version == 1 {
+      signatures = prefix
+        .inputs
+        .iter()
+        .filter_map(|input| match input {
+          Input::ToKey { key_offsets, .. } => Some(
+            key_offsets
+              .iter()
+              .map(|_| Ok((read_scalar(r)?, read_scalar(r)?)))
+              .collect::<Result<_, io::Error>>(),
+          ),
+          _ => None,
+        })
+        .collect::<Result<_, _>>()?;
+
+      rct_signatures.base.fee = prefix
+        .inputs
+        .iter()
+        .map(|input| match input {
+          Input::Gen(..) => 0,
+          Input::ToKey { amount, .. } => amount.unwrap(),
+        })
+        .sum::<u64>()
+        .saturating_sub(prefix.outputs.iter().map(|output| output.amount.unwrap()).sum());
+    } else if prefix.version == 2 {
+      rct_signatures = RctSignatures::read(
+        prefix
+          .inputs
+          .iter()
+          .map(|input| match input {
+            Input::Gen(_) => 0,
+            Input::ToKey { key_offsets, .. } => key_offsets.len(),
+          })
+          .collect(),
+        prefix.outputs.len(),
+        r,
+      )?;
+    } else {
+      Err(io::Error::new(io::ErrorKind::Other, "Tried to deserialize unknown version"))?;
+    }
+
+    Ok(Self { prefix, signatures, rct_signatures })
+  }
+
+  pub fn hash(&self) -> [u8; 32] {
+    let mut buf = Vec::with_capacity(2048);
+    if self.prefix.version == 1 {
+      self.write(&mut buf).unwrap();
+      hash(&buf)
+    } else {
+      let mut hashes = Vec::with_capacity(96);
+
+      hashes.extend(self.prefix.hash());
+
+      self.rct_signatures.base.write(&mut buf, self.rct_signatures.rct_type()).unwrap();
+      hashes.extend(hash(&buf));
+      buf.clear();
+
+      hashes.extend(&match self.rct_signatures.prunable {
+        RctPrunable::Null => [0; 32],
+        RctPrunable::MlsagBorromean { .. } |
+        RctPrunable::MlsagBulletproofs { .. } |
+        RctPrunable::Clsag { .. } => {
+          self.rct_signatures.prunable.write(&mut buf, self.rct_signatures.rct_type()).unwrap();
+          hash(&buf)
+        }
+      });
+
+      hash(&hashes)
+    }
+  }
+
+  /// Calculate the hash of this transaction as needed for signing it.
   pub fn signature_hash(&self) -> [u8; 32] {
-    let mut serialized = Vec::with_capacity(2048);
+    let mut buf = Vec::with_capacity(2048);
     let mut sig_hash = Vec::with_capacity(96);
 
-    self.prefix.serialize(&mut serialized).unwrap();
-    sig_hash.extend(hash(&serialized));
-    serialized.clear();
+    sig_hash.extend(self.prefix.hash());
 
-    self.rct_signatures.base.serialize(&mut serialized, self.rct_signatures.prunable.rct_type()).unwrap();
-    sig_hash.extend(hash(&serialized));
-    serialized.clear();
+    self.rct_signatures.base.write(&mut buf, self.rct_signatures.rct_type()).unwrap();
+    sig_hash.extend(hash(&buf));
+    buf.clear();
 
-    self.rct_signatures.prunable.signature_serialize(&mut serialized).unwrap();
-    sig_hash.extend(&hash(&serialized));
+    self.rct_signatures.prunable.signature_write(&mut buf).unwrap();
+    sig_hash.extend(hash(&buf));
 
     hash(&sig_hash)
   }

coins/monero/src/wallet/address.rs

@@ -1,152 +1,311 @@
-use std::string::ToString;
+use core::{marker::PhantomData, fmt::Debug};
+use std_shims::string::{String, ToString};
 
-use thiserror::Error;
+use zeroize::Zeroize;
 
-use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, edwards::{EdwardsPoint, CompressedEdwardsY}};
+use curve25519_dalek::edwards::{EdwardsPoint, CompressedEdwardsY};
 
 use base58_monero::base58::{encode_check, decode_check};
 
-use crate::wallet::ViewPair;
-
-#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+/// The network this address is for.
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
 pub enum Network {
   Mainnet,
   Testnet,
-  Stagenet
+  Stagenet,
 }
 
-#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+/// The address type, supporting the officially documented addresses, along with
+/// [Featured Addresses](https://gist.github.com/kayabaNerve/01c50bbc35441e0bbdcee63a9d823789).
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
 pub enum AddressType {
   Standard,
   Integrated([u8; 8]),
-  Subaddress
+  Subaddress,
+  Featured { subaddress: bool, payment_id: Option<[u8; 8]>, guaranteed: bool },
+}
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
+pub struct SubaddressIndex {
+  pub(crate) account: u32,
+  pub(crate) address: u32,
+}
+
+impl SubaddressIndex {
+  pub const fn new(account: u32, address: u32) -> Option<Self> {
+    if (account == 0) && (address == 0) {
+      return None;
+    }
+    Some(Self { account, address })
+  }
+
+  pub const fn account(&self) -> u32 {
+    self.account
+  }
+
+  pub const fn address(&self) -> u32 {
+    self.address
+  }
+}
+
+/// Address specification. Used internally to create addresses.
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
+pub enum AddressSpec {
+  Standard,
+  Integrated([u8; 8]),
+  Subaddress(SubaddressIndex),
+  Featured { subaddress: Option<SubaddressIndex>, payment_id: Option<[u8; 8]>, guaranteed: bool },
 }
 
 impl AddressType {
-  fn network_bytes(network: Network) -> (u8, u8, u8) {
+  pub const fn is_subaddress(&self) -> bool {
+    matches!(self, Self::Subaddress) || matches!(self, Self::Featured { subaddress: true, .. })
+  }
+
+  pub const fn payment_id(&self) -> Option<[u8; 8]> {
+    if let Self::Integrated(id) = self {
+      Some(*id)
+    } else if let Self::Featured { payment_id, .. } = self {
+      *payment_id
+    } else {
+      None
+    }
+  }
+
+  pub const fn is_guaranteed(&self) -> bool {
+    matches!(self, Self::Featured { guaranteed: true, .. })
+  }
+}
+
+/// A type which returns the byte for a given address.
+pub trait AddressBytes: Clone + Copy + PartialEq + Eq + Debug {
+  fn network_bytes(network: Network) -> (u8, u8, u8, u8);
+}
+
+/// Address bytes for Monero.
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+pub struct MoneroAddressBytes;
+impl AddressBytes for MoneroAddressBytes {
+  fn network_bytes(network: Network) -> (u8, u8, u8, u8) {
     match network {
-      Network::Mainnet => (18, 19, 42),
-      Network::Testnet => (53, 54, 63),
-      Network::Stagenet => (24, 25, 36)
+      Network::Mainnet => (18, 19, 42, 70),
+      Network::Testnet => (53, 54, 63, 111),
+      Network::Stagenet => (24, 25, 36, 86),
     }
   }
 }
 
+/// Address metadata.
 #[derive(Clone, Copy, PartialEq, Eq, Debug)]
-pub struct AddressMeta {
+pub struct AddressMeta<B: AddressBytes> {
+  _bytes: PhantomData<B>,
   pub network: Network,
   pub kind: AddressType,
-  pub guaranteed: bool
 }
 
-#[derive(Clone, Error, Debug)]
+impl<B: AddressBytes> Zeroize for AddressMeta<B> {
+  fn zeroize(&mut self) {
+    self.network.zeroize();
+    self.kind.zeroize();
+  }
+}
+
+/// Error when decoding an address.
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+#[cfg_attr(feature = "std", derive(thiserror::Error))]
 pub enum AddressError {
-  #[error("invalid address byte")]
+  #[cfg_attr(feature = "std", error("invalid address byte"))]
   InvalidByte,
-  #[error("invalid address encoding")]
+  #[cfg_attr(feature = "std", error("invalid address encoding"))]
   InvalidEncoding,
-  #[error("invalid length")]
+  #[cfg_attr(feature = "std", error("invalid length"))]
   InvalidLength,
-  #[error("different network than expected")]
+  #[cfg_attr(feature = "std", error("invalid key"))]
+  InvalidKey,
+  #[cfg_attr(feature = "std", error("unknown features"))]
+  UnknownFeatures,
+  #[cfg_attr(feature = "std", error("different network than expected"))]
   DifferentNetwork,
-  #[error("invalid key")]
-  InvalidKey
 }
 
-impl AddressMeta {
+impl<B: AddressBytes> AddressMeta<B> {
+  #[allow(clippy::wrong_self_convention)]
   fn to_byte(&self) -> u8 {
-    let bytes = AddressType::network_bytes(self.network);
-    let byte = match self.kind {
+    let bytes = B::network_bytes(self.network);
+    match self.kind {
       AddressType::Standard => bytes.0,
       AddressType::Integrated(_) => bytes.1,
-      AddressType::Subaddress => bytes.2
-    };
-    byte | (if self.guaranteed { 1 << 7 } else { 0 })
+      AddressType::Subaddress => bytes.2,
+      AddressType::Featured { .. } => bytes.3,
+    }
   }
 
-  // Returns an incomplete type in the case of Integrated addresses
-  fn from_byte(byte: u8) -> Result<AddressMeta, AddressError> {
-    let actual = byte & 0b01111111;
-    let guaranteed = (byte >> 7) == 1;
+  /// Create an address's metadata.
+  pub const fn new(network: Network, kind: AddressType) -> Self {
+    Self { _bytes: PhantomData, network, kind }
+  }
 
+  // Returns an incomplete instantiation in the case of Integrated/Featured addresses
+  fn from_byte(byte: u8) -> Result<Self, AddressError> {
     let mut meta = None;
     for network in [Network::Mainnet, Network::Testnet, Network::Stagenet] {
-      let (standard, integrated, subaddress) = AddressType::network_bytes(network);
-      if let Some(kind) = match actual {
-        _ if actual == standard => Some(AddressType::Standard),
-        _ if actual == integrated => Some(AddressType::Integrated([0; 8])),
-        _ if actual == subaddress => Some(AddressType::Subaddress),
-        _ => None
+      let (standard, integrated, subaddress, featured) = B::network_bytes(network);
+      if let Some(kind) = match byte {
+        _ if byte == standard => Some(AddressType::Standard),
+        _ if byte == integrated => Some(AddressType::Integrated([0; 8])),
+        _ if byte == subaddress => Some(AddressType::Subaddress),
+        _ if byte == featured => {
+          Some(AddressType::Featured { subaddress: false, payment_id: None, guaranteed: false })
+        }
+        _ => None,
       } {
-        meta = Some(AddressMeta { network, kind, guaranteed });
+        meta = Some(Self::new(network, kind));
         break;
       }
     }
 
     meta.ok_or(AddressError::InvalidByte)
   }
-}
 
-#[derive(Clone, Copy, PartialEq, Eq, Debug)]
-pub struct Address {
-  pub meta: AddressMeta,
-  pub spend: EdwardsPoint,
-  pub view: EdwardsPoint
-}
+  pub const fn is_subaddress(&self) -> bool {
+    self.kind.is_subaddress()
+  }
 
-impl ViewPair {
-  pub fn address(&self, network: Network, kind: AddressType, guaranteed: bool) -> Address {
-    Address {
-      meta: AddressMeta {
-        network,
-        kind,
-        guaranteed
-      },
-      spend: self.spend,
-      view: &self.view * &ED25519_BASEPOINT_TABLE
-    }
+  pub const fn payment_id(&self) -> Option<[u8; 8]> {
+    self.kind.payment_id()
+  }
+
+  pub const fn is_guaranteed(&self) -> bool {
+    self.kind.is_guaranteed()
   }
 }
 
-impl ToString for Address {
+/// A Monero address, composed of metadata and a spend/view key.
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+pub struct Address<B: AddressBytes> {
+  pub meta: AddressMeta<B>,
+  pub spend: EdwardsPoint,
+  pub view: EdwardsPoint,
+}
+
+impl<B: AddressBytes> Zeroize for Address<B> {
+  fn zeroize(&mut self) {
+    self.meta.zeroize();
+    self.spend.zeroize();
+    self.view.zeroize();
+  }
+}
+
+impl<B: AddressBytes> ToString for Address<B> {
   fn to_string(&self) -> String {
     let mut data = vec![self.meta.to_byte()];
     data.extend(self.spend.compress().to_bytes());
     data.extend(self.view.compress().to_bytes());
-    if let AddressType::Integrated(id) = self.meta.kind {
+    if let AddressType::Featured { subaddress, payment_id, guaranteed } = self.meta.kind {
+      // Technically should be a VarInt, yet we don't have enough features it's needed
+      data.push(
+        u8::from(subaddress) + (u8::from(payment_id.is_some()) << 1) + (u8::from(guaranteed) << 2),
+      );
+    }
+    if let Some(id) = self.meta.kind.payment_id() {
       data.extend(id);
     }
     encode_check(&data).unwrap()
   }
 }
 
-impl Address {
-  pub fn from_str(s: &str, network: Network) -> Result<Self, AddressError> {
+impl<B: AddressBytes> Address<B> {
+  pub const fn new(meta: AddressMeta<B>, spend: EdwardsPoint, view: EdwardsPoint) -> Self {
+    Self { meta, spend, view }
+  }
+
+  pub fn from_str_raw(s: &str) -> Result<Self, AddressError> {
     let raw = decode_check(s).map_err(|_| AddressError::InvalidEncoding)?;
-    if raw.len() == 1 {
+    if raw.len() < (1 + 32 + 32) {
       Err(AddressError::InvalidLength)?;
     }
 
     let mut meta = AddressMeta::from_byte(raw[0])?;
-    if meta.network != network {
-      Err(AddressError::DifferentNetwork)?;
+    let spend = CompressedEdwardsY(raw[1 .. 33].try_into().unwrap())
+      .decompress()
+      .ok_or(AddressError::InvalidKey)?;
+    let view = CompressedEdwardsY(raw[33 .. 65].try_into().unwrap())
+      .decompress()
+      .ok_or(AddressError::InvalidKey)?;
+    let mut read = 65;
+
+    if matches!(meta.kind, AddressType::Featured { .. }) {
+      if raw[read] >= (2 << 3) {
+        Err(AddressError::UnknownFeatures)?;
+      }
+
+      let subaddress = (raw[read] & 1) == 1;
+      let integrated = ((raw[read] >> 1) & 1) == 1;
+      let guaranteed = ((raw[read] >> 2) & 1) == 1;
+
+      meta.kind = AddressType::Featured {
+        subaddress,
+        payment_id: Some([0; 8]).filter(|_| integrated),
+        guaranteed,
+      };
+      read += 1;
     }
 
-    let len = match meta.kind {
-      AddressType::Standard | AddressType::Subaddress => 65,
-      AddressType::Integrated(_) => 73
-    };
-    if raw.len() != len {
+    // Update read early so we can verify the length
+    if meta.kind.payment_id().is_some() {
+      read += 8;
+    }
+    if raw.len() != read {
       Err(AddressError::InvalidLength)?;
     }
 
-    let spend = CompressedEdwardsY(raw[1 .. 33].try_into().unwrap()).decompress().ok_or(AddressError::InvalidKey)?;
-    let view = CompressedEdwardsY(raw[33 .. 65].try_into().unwrap()).decompress().ok_or(AddressError::InvalidKey)?;
-
-    if let AddressType::Integrated(ref mut payment_id) = meta.kind {
-      payment_id.copy_from_slice(&raw[65 .. 73]);
+    if let AddressType::Integrated(ref mut id) = meta.kind {
+      id.copy_from_slice(&raw[(read - 8) .. read]);
+    }
+    if let AddressType::Featured { payment_id: Some(ref mut id), .. } = meta.kind {
+      id.copy_from_slice(&raw[(read - 8) .. read]);
     }
 
-    Ok(Address { meta, spend, view })
+    Ok(Self { meta, spend, view })
+  }
+
+  pub fn from_str(network: Network, s: &str) -> Result<Self, AddressError> {
+    Self::from_str_raw(s).and_then(|addr| {
+      if addr.meta.network == network {
+        Ok(addr)
+      } else {
+        Err(AddressError::DifferentNetwork)?
+      }
+    })
+  }
+
+  pub const fn network(&self) -> Network {
+    self.meta.network
+  }
+
+  pub const fn is_subaddress(&self) -> bool {
+    self.meta.is_subaddress()
+  }
+
+  pub const fn payment_id(&self) -> Option<[u8; 8]> {
+    self.meta.payment_id()
+  }
+
+  pub const fn is_guaranteed(&self) -> bool {
+    self.meta.is_guaranteed()
+  }
+}
+
+/// Instantiation of the Address type with Monero's network bytes.
+pub type MoneroAddress = Address<MoneroAddressBytes>;
+// Allow re-interpreting of an arbitrary address as a Monero address so it can be used with the
+// rest of this library. Doesn't use From as it was conflicting with From<T> for T.
+impl MoneroAddress {
+  pub const fn from<B: AddressBytes>(address: Address<B>) -> Self {
+    Self::new(
+      AddressMeta::new(address.meta.network, address.meta.kind),
+      address.spend,
+      address.view,
+    )
   }
 }

coins/monero/src/wallet/decoys.rs

@@ -1,51 +1,76 @@
-use std::{sync::Mutex, collections::HashSet};
+use std_shims::{sync::OnceLock, vec::Vec, collections::HashSet};
 
-use lazy_static::lazy_static;
+#[cfg(not(feature = "std"))]
+use std_shims::sync::Mutex;
+#[cfg(feature = "std")]
+use futures::lock::Mutex;
+
+use zeroize::{Zeroize, ZeroizeOnDrop};
 
 use rand_core::{RngCore, CryptoRng};
 use rand_distr::{Distribution, Gamma};
+#[cfg(not(feature = "std"))]
+use rand_distr::num_traits::Float;
 
 use curve25519_dalek::edwards::EdwardsPoint;
 
-use crate::{transaction::RING_LEN, wallet::SpendableOutput, rpc::{RpcError, Rpc}};
+use crate::{
+  wallet::SpendableOutput,
+  rpc::{RpcError, RpcConnection, Rpc},
+};
 
 const LOCK_WINDOW: usize = 10;
 const MATURITY: u64 = 60;
 const RECENT_WINDOW: usize = 15;
 const BLOCK_TIME: usize = 120;
 const BLOCKS_PER_YEAR: usize = 365 * 24 * 60 * 60 / BLOCK_TIME;
+#[allow(clippy::as_conversions)]
 const TIP_APPLICATION: f64 = (LOCK_WINDOW * BLOCK_TIME) as f64;
 
-const DECOYS: usize = RING_LEN - 1;
-
-lazy_static! {
-  static ref GAMMA: Gamma<f64> = Gamma::new(19.28, 1.0 / 1.61).unwrap();
-  static ref DISTRIBUTION: Mutex<Vec<u64>> = Mutex::new(Vec::with_capacity(3000000));
+// TODO: Expose an API to reset this in case a reorg occurs/the RPC fails/returns garbage
+// TODO: Update this when scanning a block, as possible
+static DISTRIBUTION_CELL: OnceLock<Mutex<Vec<u64>>> = OnceLock::new();
+#[allow(non_snake_case)]
+fn DISTRIBUTION() -> &'static Mutex<Vec<u64>> {
+  DISTRIBUTION_CELL.get_or_init(|| Mutex::new(Vec::with_capacity(3_000_000)))
 }
 
-async fn select_n<R: RngCore + CryptoRng>(
+#[allow(clippy::too_many_arguments, clippy::as_conversions)]
+async fn select_n<'a, R: Send + RngCore + CryptoRng, RPC: RpcConnection>(
   rng: &mut R,
-  rpc: &Rpc,
+  rpc: &Rpc<RPC>,
+  distribution: &[u64],
   height: usize,
   high: u64,
   per_second: f64,
+  real: &[u64],
   used: &mut HashSet<u64>,
-  count: usize
+  count: usize,
 ) -> Result<Vec<(u64, [EdwardsPoint; 2])>, RpcError> {
+  if height >= rpc.get_height().await? {
+    // TODO: Don't use InternalError for the caller's failure
+    Err(RpcError::InternalError("decoys being requested from too young blocks"))?;
+  }
+
+  #[cfg(test)]
   let mut iters = 0;
   let mut confirmed = Vec::with_capacity(count);
+  // Retries on failure. Retries are obvious as decoys, yet should be minimal
   while confirmed.len() != count {
     let remaining = count - confirmed.len();
     let mut candidates = Vec::with_capacity(remaining);
     while candidates.len() != remaining {
-      iters += 1;
-      // This is cheap and on fresh chains, thousands of rounds may be needed
-      if iters == 10000 {
-        Err(RpcError::InternalError("not enough decoy candidates".to_string()))?;
+      #[cfg(test)]
+      {
+        iters += 1;
+        // This is cheap and on fresh chains, a lot of rounds may be needed
+        if iters == 100 {
+          Err(RpcError::InternalError("hit decoy selection round limit"))?;
+        }
       }
 
       // Use a gamma distribution
-      let mut age = GAMMA.sample(rng).exp();
+      let mut age = Gamma::<f64>::new(19.28, 1.0 / 1.61).unwrap().sample(rng).exp();
       if age > TIP_APPLICATION {
         age -= TIP_APPLICATION;
       } else {
@@ -55,7 +80,6 @@ async fn select_n<R: RngCore + CryptoRng>(
 
       let o = (age * per_second) as u64;
       if o < high {
-        let distribution = DISTRIBUTION.lock().unwrap();
         let i = distribution.partition_point(|s| *s < (high - 1 - o));
         let prev = i.saturating_sub(1);
         let n = distribution[i] - distribution[prev];
@@ -70,9 +94,28 @@ async fn select_n<R: RngCore + CryptoRng>(
       }
     }
 
-    let outputs = rpc.get_outputs(&candidates, height).await?;
-    for i in 0 .. outputs.len() {
-      if let Some(output) = outputs[i] {
+    // If this is the first time we're requesting these outputs, include the real one as well
+    // Prevents the node we're connected to from having a list of known decoys and then seeing a
+    // TX which uses all of them, with one additional output (the true spend)
+    let mut real_indexes = HashSet::with_capacity(real.len());
+    if confirmed.is_empty() {
+      for real in real {
+        candidates.push(*real);
+      }
+      // Sort candidates so the real spends aren't the ones at the end
+      candidates.sort();
+      for real in real {
+        real_indexes.insert(candidates.binary_search(real).unwrap());
+      }
+    }
+
+    for (i, output) in rpc.get_unlocked_outputs(&candidates, height).await?.iter_mut().enumerate() {
+      // Don't include the real spend as a decoy, despite requesting it
+      if real_indexes.contains(&i) {
+        continue;
+      }
+
+      if let Some(output) = output.take() {
         confirmed.push((candidates[i], output));
       }
     }
@@ -90,11 +133,12 @@ fn offset(ring: &[u64]) -> Vec<u64> {
   res
 }
 
-#[derive(Clone, PartialEq, Debug)]
+/// Decoy data, containing the actual member as well (at index `i`).
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
 pub struct Decoys {
   pub i: u8,
   pub offsets: Vec<u64>,
-  pub ring: Vec<[EdwardsPoint; 2]>
+  pub ring: Vec<[EdwardsPoint; 2]>,
 }
 
 impl Decoys {
@@ -102,44 +146,43 @@ impl Decoys {
     self.offsets.len()
   }
 
-  pub(crate) async fn select<R: RngCore + CryptoRng>(
+  /// Select decoys using the same distribution as Monero.
+  #[allow(clippy::as_conversions)]
+  pub async fn select<R: Send + RngCore + CryptoRng, RPC: RpcConnection>(
     rng: &mut R,
-    rpc: &Rpc,
+    rpc: &Rpc<RPC>,
+    ring_len: usize,
     height: usize,
-    inputs: &[SpendableOutput]
-  ) -> Result<Vec<Decoys>, RpcError> {
+    inputs: &[SpendableOutput],
+  ) -> Result<Vec<Self>, RpcError> {
+    #[cfg(not(feature = "std"))]
+    let mut distribution = DISTRIBUTION().lock();
+    #[cfg(feature = "std")]
+    let mut distribution = DISTRIBUTION().lock().await;
+
+    let decoy_count = ring_len - 1;
+
     // Convert the inputs in question to the raw output data
+    let mut real = Vec::with_capacity(inputs.len());
     let mut outputs = Vec::with_capacity(inputs.len());
     for input in inputs {
-      outputs.push((
-        rpc.get_o_indexes(input.tx).await?[usize::from(input.o)],
-        [input.key, input.commitment.calculate()]
-      ));
+      real.push(input.global_index);
+      outputs.push((real[real.len() - 1], [input.key(), input.commitment().calculate()]));
     }
 
-    let distribution_len = {
-      let distribution = DISTRIBUTION.lock().unwrap();
-      distribution.len()
-    };
-    if distribution_len <= height {
-      let extension = rpc.get_output_distribution(distribution_len, height).await?;
-      DISTRIBUTION.lock().unwrap().extend(extension);
+    if distribution.len() <= height {
+      let extension = rpc.get_output_distribution(distribution.len(), height).await?;
+      distribution.extend(extension);
     }
+    // If asked to use an older height than previously asked, truncate to ensure accuracy
+    // Should never happen, yet risks desyncing if it did
+    distribution.truncate(height + 1); // height is inclusive, and 0 is a valid height
 
-    let high;
-    let per_second;
-    {
-      let mut distribution = DISTRIBUTION.lock().unwrap();
-      // If asked to use an older height than previously asked, truncate to ensure accuracy
-      // Should never happen, yet risks desyncing if it did
-      distribution.truncate(height + 1); // height is inclusive, and 0 is a valid height
-
-      high = distribution[distribution.len() - 1];
-      per_second = {
-        let blocks = distribution.len().min(BLOCKS_PER_YEAR);
-        let outputs = high - distribution[distribution.len().saturating_sub(blocks + 1)];
-        (outputs as f64) / ((blocks * BLOCK_TIME) as f64)
-      };
+    let high = distribution[distribution.len() - 1];
+    let per_second = {
+      let blocks = distribution.len().min(BLOCKS_PER_YEAR);
+      let outputs = high - distribution[distribution.len().saturating_sub(blocks + 1)];
+      (outputs as f64) / ((blocks * BLOCK_TIME) as f64)
     };
 
     let mut used = HashSet::<u64>::new();
@@ -147,28 +190,32 @@ impl Decoys {
       used.insert(o.0);
     }
 
-    // TODO: Simply create a TX with less than the target amount
-    if (high - MATURITY) < u64::try_from(inputs.len() * RING_LEN).unwrap() {
-      Err(RpcError::InternalError("not enough decoy candidates".to_string()))?;
+    // TODO: Create a TX with less than the target amount, as allowed by the protocol
+    if (high - MATURITY) < u64::try_from(inputs.len() * ring_len).unwrap() {
+      Err(RpcError::InternalError("not enough decoy candidates"))?;
     }
 
     // Select all decoys for this transaction, assuming we generate a sane transaction
-    // We should almost never naturally generate an insane transaction, hence why this doesn't bother
-    // with an overage
+    // We should almost never naturally generate an insane transaction, hence why this doesn't
+    // bother with an overage
     let mut decoys = select_n(
       rng,
       rpc,
+      &distribution,
       height,
       high,
       per_second,
+      &real,
       &mut used,
-      inputs.len() * DECOYS
-    ).await?;
+      inputs.len() * decoy_count,
+    )
+    .await?;
+    real.zeroize();
 
     let mut res = Vec::with_capacity(inputs.len());
     for o in outputs {
       // Grab the decoys for this specific output
-      let mut ring = decoys.drain((decoys.len() - DECOYS) ..).collect::<Vec<_>>();
+      let mut ring = decoys.drain((decoys.len() - decoy_count) ..).collect::<Vec<_>>();
       ring.push(o);
       ring.sort_by(|a, b| a.0.cmp(&b.0));
 
@@ -178,40 +225,54 @@ impl Decoys {
       // 500 outputs since while itself not being a sufficiently mature blockchain
       // Considering Monero's p2p layer doesn't actually check transaction sanity, it should be
       // fine for us to not have perfectly matching rules, especially since this code will infinite
-      // loop if it can't determine sanity, which is possible with sufficient inputs on sufficiently
-      // small chains
+      // loop if it can't determine sanity, which is possible with sufficient inputs on
+      // sufficiently small chains
       if high > 500 {
         // Make sure the TX passes the sanity check that the median output is within the last 40%
         let target_median = high * 3 / 5;
-        while ring[RING_LEN / 2].0 < target_median {
+        while ring[ring_len / 2].0 < target_median {
           // If it's not, update the bottom half with new values to ensure the median only moves up
-          for removed in ring.drain(0 .. (RING_LEN / 2)).collect::<Vec<_>>() {
+          #[allow(clippy::needless_collect)] // Needed for ownership reasons
+          for removed in ring.drain(0 .. (ring_len / 2)).collect::<Vec<_>>() {
             // If we removed the real spend, add it back
             if removed.0 == o.0 {
               ring.push(o);
             } else {
-              // We could not remove this, saving CPU time and removing low values as possibilities, yet
-              // it'd increase the amount of decoys required to create this transaction and some removed
-              // outputs may be the best option (as we drop the first half, not just the bottom n)
+              // We could not remove this, saving CPU time and removing low values as
+              // possibilities, yet it'd increase the amount of decoys required to create this
+              // transaction and some removed outputs may be the best option (as we drop the first
+              // half, not just the bottom n)
               used.remove(&removed.0);
             }
           }
 
           // Select new outputs until we have a full sized ring again
           ring.extend(
-            select_n(rng, rpc, height, high, per_second, &mut used, RING_LEN - ring.len()).await?
+            select_n(
+              rng,
+              rpc,
+              &distribution,
+              height,
+              high,
+              per_second,
+              &[],
+              &mut used,
+              ring_len - ring.len(),
+            )
+            .await?,
           );
           ring.sort_by(|a, b| a.0.cmp(&b.0));
         }
 
-        // The other sanity check rule is about duplicates, yet we already enforce unique ring members
+        // The other sanity check rule is about duplicates, yet we already enforce unique ring
+        // members
       }
 
-      res.push(Decoys {
+      res.push(Self {
         // Binary searches for the real spend since we don't know where it sorted to
         i: u8::try_from(ring.partition_point(|x| x.0 < o.0)).unwrap(),
         offsets: offset(&ring.iter().map(|output| output.0).collect::<Vec<_>>()),
-        ring: ring.iter().map(|output| output.1).collect()
+        ring: ring.iter().map(|output| output.1).collect(),
       });
     }
 

coins/monero/src/wallet/extra.rs

@@ -0,0 +1,218 @@
+use core::ops::BitXor;
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
+};
+
+use zeroize::Zeroize;
+
+use curve25519_dalek::edwards::EdwardsPoint;
+
+use crate::serialize::{
+  varint_len, read_byte, read_bytes, read_varint, read_point, read_vec, write_byte, write_varint,
+  write_point, write_vec,
+};
+
+pub const MAX_TX_EXTRA_NONCE_SIZE: usize = 255;
+
+pub const PAYMENT_ID_MARKER: u8 = 0;
+pub const ENCRYPTED_PAYMENT_ID_MARKER: u8 = 1;
+// Used as it's the highest value not interpretable as a continued VarInt
+pub const ARBITRARY_DATA_MARKER: u8 = 127;
+
+// 1 byte is used for the marker
+pub const MAX_ARBITRARY_DATA_SIZE: usize = MAX_TX_EXTRA_NONCE_SIZE - 1;
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
+pub enum PaymentId {
+  Unencrypted([u8; 32]),
+  Encrypted([u8; 8]),
+}
+
+impl BitXor<[u8; 8]> for PaymentId {
+  type Output = Self;
+
+  fn bitxor(self, bytes: [u8; 8]) -> Self {
+    match self {
+      // Don't perform the xor since this isn't intended to be encrypted with xor
+      Self::Unencrypted(_) => self,
+      Self::Encrypted(id) => {
+        Self::Encrypted((u64::from_le_bytes(id) ^ u64::from_le_bytes(bytes)).to_le_bytes())
+      }
+    }
+  }
+}
+
+impl PaymentId {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    match self {
+      Self::Unencrypted(id) => {
+        w.write_all(&[PAYMENT_ID_MARKER])?;
+        w.write_all(id)?;
+      }
+      Self::Encrypted(id) => {
+        w.write_all(&[ENCRYPTED_PAYMENT_ID_MARKER])?;
+        w.write_all(id)?;
+      }
+    }
+    Ok(())
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(match read_byte(r)? {
+      0 => Self::Unencrypted(read_bytes(r)?),
+      1 => Self::Encrypted(read_bytes(r)?),
+      _ => Err(io::Error::new(io::ErrorKind::Other, "unknown payment ID type"))?,
+    })
+  }
+}
+
+// Doesn't bother with padding nor MinerGate
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize)]
+pub enum ExtraField {
+  PublicKey(EdwardsPoint),
+  Nonce(Vec<u8>),
+  MergeMining(usize, [u8; 32]),
+  PublicKeys(Vec<EdwardsPoint>),
+}
+
+impl ExtraField {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    match self {
+      Self::PublicKey(key) => {
+        w.write_all(&[1])?;
+        w.write_all(&key.compress().to_bytes())?;
+      }
+      Self::Nonce(data) => {
+        w.write_all(&[2])?;
+        write_vec(write_byte, data, w)?;
+      }
+      Self::MergeMining(height, merkle) => {
+        w.write_all(&[3])?;
+        write_varint(&u64::try_from(*height).unwrap(), w)?;
+        w.write_all(merkle)?;
+      }
+      Self::PublicKeys(keys) => {
+        w.write_all(&[4])?;
+        write_vec(write_point, keys, w)?;
+      }
+    }
+    Ok(())
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(match read_byte(r)? {
+      1 => Self::PublicKey(read_point(r)?),
+      2 => Self::Nonce({
+        let nonce = read_vec(read_byte, r)?;
+        if nonce.len() > MAX_TX_EXTRA_NONCE_SIZE {
+          Err(io::Error::new(io::ErrorKind::Other, "too long nonce"))?;
+        }
+        nonce
+      }),
+      3 => Self::MergeMining(
+        usize::try_from(read_varint(r)?)
+          .map_err(|_| io::Error::new(io::ErrorKind::Other, "varint for height exceeds usize"))?,
+        read_bytes(r)?,
+      ),
+      4 => Self::PublicKeys(read_vec(read_point, r)?),
+      _ => Err(io::Error::new(io::ErrorKind::Other, "unknown extra field"))?,
+    })
+  }
+}
+
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize)]
+pub struct Extra(Vec<ExtraField>);
+impl Extra {
+  pub fn keys(&self) -> Option<(EdwardsPoint, Option<Vec<EdwardsPoint>>)> {
+    let mut key = None;
+    let mut additional = None;
+    for field in &self.0 {
+      match field.clone() {
+        ExtraField::PublicKey(this_key) => key = key.or(Some(this_key)),
+        ExtraField::PublicKeys(these_additional) => {
+          additional = additional.or(Some(these_additional));
+        }
+        ExtraField::Nonce(_) | ExtraField::MergeMining(..) => (),
+      }
+    }
+    // Don't return any keys if this was non-standard and didn't include the primary key
+    key.map(|key| (key, additional))
+  }
+
+  pub fn payment_id(&self) -> Option<PaymentId> {
+    for field in &self.0 {
+      if let ExtraField::Nonce(data) = field {
+        return PaymentId::read::<&[u8]>(&mut data.as_ref()).ok();
+      }
+    }
+    None
+  }
+
+  pub fn data(&self) -> Vec<Vec<u8>> {
+    let mut res = vec![];
+    for field in &self.0 {
+      if let ExtraField::Nonce(data) = field {
+        if data[0] == ARBITRARY_DATA_MARKER {
+          res.push(data[1 ..].to_vec());
+        }
+      }
+    }
+    res
+  }
+
+  pub(crate) fn new(key: EdwardsPoint, additional: Vec<EdwardsPoint>) -> Self {
+    let mut res = Self(Vec::with_capacity(3));
+    res.push(ExtraField::PublicKey(key));
+    if !additional.is_empty() {
+      res.push(ExtraField::PublicKeys(additional));
+    }
+    res
+  }
+
+  pub(crate) fn push(&mut self, field: ExtraField) {
+    self.0.push(field);
+  }
+
+  #[rustfmt::skip]
+  pub(crate) fn fee_weight(
+    outputs: usize,
+    additional: bool,
+    payment_id: bool,
+    data: &[Vec<u8>]
+  ) -> usize {
+    // PublicKey, key
+    (1 + 32) +
+    // PublicKeys, length, additional keys
+    (if additional { 1 + 1 + (outputs * 32) } else { 0 }) +
+    // PaymentId (Nonce), length, encrypted, ID
+    (if payment_id { 1 + 1 + 1 + 8 } else { 0 }) +
+    // Nonce, length, ARBITRARY_DATA_MARKER, data
+    data.iter().map(|v| 1 + varint_len(1 + v.len()) + 1 + v.len()).sum::<usize>()
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    for field in &self.0 {
+      field.write(w)?;
+    }
+    Ok(())
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut buf = vec![];
+    self.write(&mut buf).unwrap();
+    buf
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    let mut res = Self(vec![]);
+    let mut field;
+    while {
+      field = ExtraField::read(r);
+      field.is_ok()
+    } {
+      res.0.push(field.unwrap());
+    }
+    Ok(res)
+  }
+}

coins/monero/src/wallet/mod.rs

@@ -1,25 +1,44 @@
-use curve25519_dalek::{scalar::Scalar, edwards::EdwardsPoint};
+use core::ops::Deref;
+use std_shims::collections::{HashSet, HashMap};
 
-use crate::{
-  hash, hash_to_scalar,
-  serialize::write_varint,
-  transaction::Input
+use zeroize::{Zeroize, ZeroizeOnDrop, Zeroizing};
+
+use curve25519_dalek::{
+  constants::ED25519_BASEPOINT_TABLE,
+  scalar::Scalar,
+  edwards::{EdwardsPoint, CompressedEdwardsY},
 };
 
+use crate::{
+  hash, hash_to_scalar, serialize::write_varint, ringct::EncryptedAmount, transaction::Input,
+};
+
+pub mod extra;
+pub(crate) use extra::{PaymentId, ExtraField, Extra};
+
+/// Seed creation and parsing functionality.
+pub mod seed;
+
+/// Address encoding and decoding functionality.
 pub mod address;
+use address::{Network, AddressType, SubaddressIndex, AddressSpec, AddressMeta, MoneroAddress};
 
 mod scan;
-pub use scan::SpendableOutput;
+pub use scan::{ReceivedOutput, SpendableOutput, Timelocked};
 
 pub(crate) mod decoys;
 pub(crate) use decoys::Decoys;
 
 mod send;
-pub use send::{Fee, TransactionError, SignableTransaction};
+pub use send::{Fee, TransactionError, Change, SignableTransaction, Eventuality};
+#[cfg(feature = "std")]
+pub use send::SignableTransactionBuilder;
+#[cfg(feature = "multisig")]
+pub(crate) use send::InternalPayment;
 #[cfg(feature = "multisig")]
 pub use send::TransactionMachine;
 
-fn key_image_sort(x: &EdwardsPoint, y: &EdwardsPoint) -> std::cmp::Ordering {
+fn key_image_sort(x: &EdwardsPoint, y: &EdwardsPoint) -> core::cmp::Ordering {
   x.compress().to_bytes().cmp(&y.compress().to_bytes()).reverse()
 }
 
@@ -30,34 +49,43 @@ pub(crate) fn uniqueness(inputs: &[Input]) -> [u8; 32] {
     match input {
       // If Gen, this should be the only input, making this loop somewhat pointless
       // This works and even if there were somehow multiple inputs, it'd be a false negative
-      Input::Gen(height) => { write_varint(&(*height).try_into().unwrap(), &mut u).unwrap(); },
-      Input::ToKey { key_image, .. } => u.extend(key_image.compress().to_bytes())
+      Input::Gen(height) => {
+        write_varint(height, &mut u).unwrap();
+      }
+      Input::ToKey { key_image, .. } => u.extend(key_image.compress().to_bytes()),
     }
   }
   hash(&u)
 }
 
-// Hs(8Ra || o) with https://github.com/monero-project/research-lab/issues/103 as an option
+// Hs("view_tag" || 8Ra || o), Hs(8Ra || o), and H(8Ra || 0x8d) with uniqueness inclusion in the
+// Scalar as an option
 #[allow(non_snake_case)]
-pub(crate) fn shared_key(uniqueness: Option<[u8; 32]>, s: Scalar, P: &EdwardsPoint, o: usize) -> Scalar {
-  // uniqueness
-  let mut shared = uniqueness.map_or(vec![], |uniqueness| uniqueness.to_vec());
-  // || 8Ra
-  shared.extend((s * P).mul_by_cofactor().compress().to_bytes().to_vec());
+pub(crate) fn shared_key(
+  uniqueness: Option<[u8; 32]>,
+  ecdh: EdwardsPoint,
+  o: usize,
+) -> (u8, Scalar, [u8; 8]) {
+  // 8Ra
+  let mut output_derivation = ecdh.mul_by_cofactor().compress().to_bytes().to_vec();
+
+  let mut payment_id_xor = [0; 8];
+  payment_id_xor
+    .copy_from_slice(&hash(&[output_derivation.as_ref(), [0x8d].as_ref()].concat())[.. 8]);
+
   // || o
-  write_varint(&o.try_into().unwrap(), &mut shared).unwrap();
-  // Hs()
-  hash_to_scalar(&shared)
-}
+  write_varint(&o.try_into().unwrap(), &mut output_derivation).unwrap();
 
-pub(crate) fn amount_encryption(amount: u64, key: Scalar) -> [u8; 8] {
-  let mut amount_mask = b"amount".to_vec();
-  amount_mask.extend(key.to_bytes());
-  (amount ^ u64::from_le_bytes(hash(&amount_mask)[0 .. 8].try_into().unwrap())).to_le_bytes()
-}
+  let view_tag = hash(&[b"view_tag".as_ref(), &output_derivation].concat())[0];
 
-fn amount_decryption(amount: [u8; 8], key: Scalar) -> u64 {
-  u64::from_le_bytes(amount_encryption(u64::from_le_bytes(amount), key))
+  // uniqueness ||
+  let shared_key = if let Some(uniqueness) = uniqueness {
+    [uniqueness.as_ref(), &output_derivation].concat()
+  } else {
+    output_derivation
+  };
+
+  (view_tag, hash_to_scalar(&shared_key), payment_id_xor)
 }
 
 pub(crate) fn commitment_mask(shared_key: Scalar) -> Scalar {
@@ -66,8 +94,175 @@ pub(crate) fn commitment_mask(shared_key: Scalar) -> Scalar {
   hash_to_scalar(&mask)
 }
 
-#[derive(Clone, Copy)]
-pub struct ViewPair {
-  pub spend: EdwardsPoint,
-  pub view: Scalar
+pub(crate) fn amount_encryption(amount: u64, key: Scalar) -> [u8; 8] {
+  let mut amount_mask = b"amount".to_vec();
+  amount_mask.extend(key.to_bytes());
+  (amount ^ u64::from_le_bytes(hash(&amount_mask)[.. 8].try_into().unwrap())).to_le_bytes()
+}
+
+// TODO: Move this under EncryptedAmount?
+fn amount_decryption(amount: &EncryptedAmount, key: Scalar) -> (Scalar, u64) {
+  match amount {
+    EncryptedAmount::Original { mask, amount } => {
+      #[cfg(feature = "experimental")]
+      {
+        let mask_shared_sec = hash(key.as_bytes());
+        let mask =
+          Scalar::from_bytes_mod_order(*mask) - Scalar::from_bytes_mod_order(mask_shared_sec);
+
+        let amount_shared_sec = hash(&mask_shared_sec);
+        let amount_scalar =
+          Scalar::from_bytes_mod_order(*amount) - Scalar::from_bytes_mod_order(amount_shared_sec);
+        // d2b from rctTypes.cpp
+        let amount = u64::from_le_bytes(amount_scalar.to_bytes()[0 .. 8].try_into().unwrap());
+
+        (mask, amount)
+      }
+
+      #[cfg(not(feature = "experimental"))]
+      {
+        let _ = mask;
+        let _ = amount;
+        todo!("decrypting a legacy monero transaction's amount")
+      }
+    }
+    EncryptedAmount::Compact { amount } => (
+      commitment_mask(key),
+      u64::from_le_bytes(amount_encryption(u64::from_le_bytes(*amount), key)),
+    ),
+  }
+}
+
+/// The private view key and public spend key, enabling scanning transactions.
+#[derive(Clone, Zeroize, ZeroizeOnDrop)]
+pub struct ViewPair {
+  spend: EdwardsPoint,
+  view: Zeroizing<Scalar>,
+}
+
+impl ViewPair {
+  pub const fn new(spend: EdwardsPoint, view: Zeroizing<Scalar>) -> Self {
+    Self { spend, view }
+  }
+
+  pub const fn spend(&self) -> EdwardsPoint {
+    self.spend
+  }
+
+  pub fn view(&self) -> EdwardsPoint {
+    self.view.deref() * &ED25519_BASEPOINT_TABLE
+  }
+
+  fn subaddress_derivation(&self, index: SubaddressIndex) -> Scalar {
+    hash_to_scalar(&Zeroizing::new(
+      [
+        b"SubAddr\0".as_ref(),
+        Zeroizing::new(self.view.to_bytes()).as_ref(),
+        &index.account().to_le_bytes(),
+        &index.address().to_le_bytes(),
+      ]
+      .concat(),
+    ))
+  }
+
+  fn subaddress_keys(&self, index: SubaddressIndex) -> (EdwardsPoint, EdwardsPoint) {
+    let scalar = self.subaddress_derivation(index);
+    let spend = self.spend + (&scalar * &ED25519_BASEPOINT_TABLE);
+    let view = self.view.deref() * spend;
+    (spend, view)
+  }
+
+  /// Returns an address with the provided specification.
+  pub fn address(&self, network: Network, spec: AddressSpec) -> MoneroAddress {
+    let mut spend = self.spend;
+    let mut view: EdwardsPoint = self.view.deref() * &ED25519_BASEPOINT_TABLE;
+
+    // construct the address meta
+    let meta = match spec {
+      AddressSpec::Standard => AddressMeta::new(network, AddressType::Standard),
+      AddressSpec::Integrated(payment_id) => {
+        AddressMeta::new(network, AddressType::Integrated(payment_id))
+      }
+      AddressSpec::Subaddress(index) => {
+        (spend, view) = self.subaddress_keys(index);
+        AddressMeta::new(network, AddressType::Subaddress)
+      }
+      AddressSpec::Featured { subaddress, payment_id, guaranteed } => {
+        if let Some(index) = subaddress {
+          (spend, view) = self.subaddress_keys(index);
+        }
+        AddressMeta::new(
+          network,
+          AddressType::Featured { subaddress: subaddress.is_some(), payment_id, guaranteed },
+        )
+      }
+    };
+
+    MoneroAddress::new(meta, spend, view)
+  }
+}
+
+/// Transaction scanner.
+/// This scanner is capable of generating subaddresses, additionally scanning for them once they've
+/// been explicitly generated. If the burning bug is attempted, any secondary outputs will be
+/// ignored.
+#[derive(Clone)]
+pub struct Scanner {
+  pair: ViewPair,
+  // Also contains the spend key as None
+  pub(crate) subaddresses: HashMap<CompressedEdwardsY, Option<SubaddressIndex>>,
+  pub(crate) burning_bug: Option<HashSet<CompressedEdwardsY>>,
+}
+
+impl Zeroize for Scanner {
+  fn zeroize(&mut self) {
+    self.pair.zeroize();
+
+    // These may not be effective, unfortunately
+    for (mut key, mut value) in self.subaddresses.drain() {
+      key.zeroize();
+      value.zeroize();
+    }
+    if let Some(ref mut burning_bug) = self.burning_bug.take() {
+      for mut output in burning_bug.drain() {
+        output.zeroize();
+      }
+    }
+  }
+}
+
+impl Drop for Scanner {
+  fn drop(&mut self) {
+    self.zeroize();
+  }
+}
+
+impl ZeroizeOnDrop for Scanner {}
+
+impl Scanner {
+  /// Create a Scanner from a ViewPair.
+  ///
+  /// burning_bug is a HashSet of used keys, intended to prevent key reuse which would burn funds.
+  ///
+  /// When an output is successfully scanned, the output key MUST be saved to disk.
+  ///
+  /// When a new scanner is created, ALL saved output keys must be passed in to be secure.
+  ///
+  /// If None is passed, a modified shared key derivation is used which is immune to the burning
+  /// bug (specifically the Guaranteed feature from Featured Addresses).
+  pub fn from_view(pair: ViewPair, burning_bug: Option<HashSet<CompressedEdwardsY>>) -> Self {
+    let mut subaddresses = HashMap::new();
+    subaddresses.insert(pair.spend.compress(), None);
+    Self { pair, subaddresses, burning_bug }
+  }
+
+  /// Register a subaddress.
+  // There used to be an address function here, yet it wasn't safe. It could generate addresses
+  // incompatible with the Scanner. While we could return None for that, then we have the issue
+  // of runtime failures to generate an address.
+  // Removing that API was the simplest option.
+  pub fn register_subaddress(&mut self, subaddress: SubaddressIndex) {
+    let (spend, _) = self.pair.subaddress_keys(subaddress);
+    self.subaddresses.insert(spend.compress(), Some(subaddress));
+  }
 }

coins/monero/src/wallet/scan.rs

@@ -1,154 +1,414 @@
-use std::convert::TryFrom;
-
-use curve25519_dalek::{
-  constants::ED25519_BASEPOINT_TABLE,
-  scalar::Scalar,
-  edwards::EdwardsPoint
+use core::ops::Deref;
+use std_shims::{
+  vec::Vec,
+  io::{self, Read, Write},
 };
 
-use monero::{consensus::deserialize, blockdata::transaction::ExtraField};
+use zeroize::{Zeroize, ZeroizeOnDrop};
+
+use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, scalar::Scalar, edwards::EdwardsPoint};
 
 use crate::{
   Commitment,
-  serialize::{write_varint, read_32, read_scalar, read_point},
-  transaction::{Timelock, Transaction},
-  wallet::{ViewPair, uniqueness, shared_key, amount_decryption, commitment_mask}
+  serialize::{read_byte, read_u32, read_u64, read_bytes, read_scalar, read_point, read_raw_vec},
+  transaction::{Input, Timelock, Transaction},
+  block::Block,
+  rpc::{RpcError, RpcConnection, Rpc},
+  wallet::{
+    PaymentId, Extra, address::SubaddressIndex, Scanner, uniqueness, shared_key, amount_decryption,
+  },
 };
 
-#[derive(Clone, PartialEq, Debug)]
-pub struct SpendableOutput {
+/// An absolute output ID, defined as its transaction hash and output index.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub struct AbsoluteId {
   pub tx: [u8; 32],
   pub o: u8,
-  pub key: EdwardsPoint,
-  pub key_offset: Scalar,
-  pub commitment: Commitment
 }
 
-pub struct Timelocked(Timelock, Vec<SpendableOutput>);
-impl Timelocked {
+impl AbsoluteId {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    w.write_all(&self.tx)?;
+    w.write_all(&[self.o])
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = Vec::with_capacity(32 + 1);
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self { tx: read_bytes(r)?, o: read_byte(r)? })
+  }
+}
+
+/// The data contained with an output.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub struct OutputData {
+  pub key: EdwardsPoint,
+  /// Absolute difference between the spend key and the key in this output
+  pub key_offset: Scalar,
+  pub commitment: Commitment,
+}
+
+impl OutputData {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    w.write_all(&self.key.compress().to_bytes())?;
+    w.write_all(&self.key_offset.to_bytes())?;
+    w.write_all(&self.commitment.mask.to_bytes())?;
+    w.write_all(&self.commitment.amount.to_le_bytes())
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = Vec::with_capacity(32 + 32 + 32 + 8);
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self {
+      key: read_point(r)?,
+      key_offset: read_scalar(r)?,
+      commitment: Commitment::new(read_scalar(r)?, read_u64(r)?),
+    })
+  }
+}
+
+/// The metadata for an output.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub struct Metadata {
+  /// The subaddress this output was sent to.
+  pub subaddress: Option<SubaddressIndex>,
+  /// The payment ID included with this output.
+  /// This will be gibberish if the payment ID wasn't intended for the recipient or wasn't included.
+  // Could be an Option, as extra doesn't necessarily have a payment ID, yet all Monero TXs should
+  // have this making it simplest for it to be as-is.
+  pub payment_id: [u8; 8],
+  /// Arbitrary data encoded in TX extra.
+  pub arbitrary_data: Vec<Vec<u8>>,
+}
+
+impl Metadata {
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    if let Some(subaddress) = self.subaddress {
+      w.write_all(&[1])?;
+      w.write_all(&subaddress.account().to_le_bytes())?;
+      w.write_all(&subaddress.address().to_le_bytes())?;
+    } else {
+      w.write_all(&[0])?;
+    }
+    w.write_all(&self.payment_id)?;
+
+    w.write_all(&u32::try_from(self.arbitrary_data.len()).unwrap().to_le_bytes())?;
+    for part in &self.arbitrary_data {
+      w.write_all(&[u8::try_from(part.len()).unwrap()])?;
+      w.write_all(part)?;
+    }
+    Ok(())
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = Vec::with_capacity(1 + 8 + 1);
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    #[allow(clippy::if_then_some_else_none)] // The Result usage makes this invalid
+    let subaddress = if read_byte(r)? == 1 {
+      Some(
+        SubaddressIndex::new(read_u32(r)?, read_u32(r)?)
+          .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "invalid subaddress in metadata"))?,
+      )
+    } else {
+      None
+    };
+
+    Ok(Self {
+      subaddress,
+      payment_id: read_bytes(r)?,
+      arbitrary_data: {
+        let mut data = vec![];
+        for _ in 0 .. read_u32(r)? {
+          let len = read_byte(r)?;
+          data.push(read_raw_vec(read_byte, usize::from(len), r)?);
+        }
+        data
+      },
+    })
+  }
+}
+
+/// A received output, defined as its absolute ID, data, and metadara.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub struct ReceivedOutput {
+  pub absolute: AbsoluteId,
+  pub data: OutputData,
+  pub metadata: Metadata,
+}
+
+impl ReceivedOutput {
+  pub fn key(&self) -> EdwardsPoint {
+    self.data.key
+  }
+
+  pub fn key_offset(&self) -> Scalar {
+    self.data.key_offset
+  }
+
+  pub fn commitment(&self) -> Commitment {
+    self.data.commitment.clone()
+  }
+
+  pub fn arbitrary_data(&self) -> &[Vec<u8>] {
+    &self.metadata.arbitrary_data
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.absolute.write(w)?;
+    self.data.write(w)?;
+    self.metadata.write(w)
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self {
+      absolute: AbsoluteId::read(r)?,
+      data: OutputData::read(r)?,
+      metadata: Metadata::read(r)?,
+    })
+  }
+}
+
+/// A spendable output, defined as a received output and its index on the Monero blockchain.
+/// This index is dependent on the Monero blockchain and will only be known once the output is
+/// included within a block. This may change if there's a reorganization.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
+pub struct SpendableOutput {
+  pub output: ReceivedOutput,
+  pub global_index: u64,
+}
+
+impl SpendableOutput {
+  /// Update the spendable output's global index. This is intended to be called if a
+  /// re-organization occurred.
+  pub async fn refresh_global_index<RPC: RpcConnection>(
+    &mut self,
+    rpc: &Rpc<RPC>,
+  ) -> Result<(), RpcError> {
+    self.global_index =
+      rpc.get_o_indexes(self.output.absolute.tx).await?[usize::from(self.output.absolute.o)];
+    Ok(())
+  }
+
+  pub async fn from<RPC: RpcConnection>(
+    rpc: &Rpc<RPC>,
+    output: ReceivedOutput,
+  ) -> Result<Self, RpcError> {
+    let mut output = Self { output, global_index: 0 };
+    output.refresh_global_index(rpc).await?;
+    Ok(output)
+  }
+
+  pub fn key(&self) -> EdwardsPoint {
+    self.output.key()
+  }
+
+  pub fn key_offset(&self) -> Scalar {
+    self.output.key_offset()
+  }
+
+  pub fn commitment(&self) -> Commitment {
+    self.output.commitment()
+  }
+
+  pub fn arbitrary_data(&self) -> &[Vec<u8>] {
+    self.output.arbitrary_data()
+  }
+
+  pub fn write<W: Write>(&self, w: &mut W) -> io::Result<()> {
+    self.output.write(w)?;
+    w.write_all(&self.global_index.to_le_bytes())
+  }
+
+  pub fn serialize(&self) -> Vec<u8> {
+    let mut serialized = vec![];
+    self.write(&mut serialized).unwrap();
+    serialized
+  }
+
+  pub fn read<R: Read>(r: &mut R) -> io::Result<Self> {
+    Ok(Self { output: ReceivedOutput::read(r)?, global_index: read_u64(r)? })
+  }
+}
+
+/// A collection of timelocked outputs, either received or spendable.
+#[derive(Zeroize)]
+pub struct Timelocked<O: Clone + Zeroize>(Timelock, Vec<O>);
+impl<O: Clone + Zeroize> Drop for Timelocked<O> {
+  fn drop(&mut self) {
+    self.zeroize();
+  }
+}
+impl<O: Clone + Zeroize> ZeroizeOnDrop for Timelocked<O> {}
+
+impl<O: Clone + Zeroize> Timelocked<O> {
   pub fn timelock(&self) -> Timelock {
     self.0
   }
 
-  pub fn not_locked(&self) -> Vec<SpendableOutput> {
+  /// Return the outputs if they're not timelocked, or an empty vector if they are.
+  #[must_use]
+  pub fn not_locked(&self) -> Vec<O> {
     if self.0 == Timelock::None {
       return self.1.clone();
     }
     vec![]
   }
 
-  /// Returns None if the Timelocks aren't comparable. Returns Some(vec![]) if none are unlocked
-  pub fn unlocked(&self, timelock: Timelock) -> Option<Vec<SpendableOutput>> {
+  /// Returns None if the Timelocks aren't comparable. Returns Some(vec![]) if none are unlocked.
+  #[must_use]
+  pub fn unlocked(&self, timelock: Timelock) -> Option<Vec<O>> {
     // If the Timelocks are comparable, return the outputs if they're now unlocked
-    self.0.partial_cmp(&timelock).filter(|_| self.0 <= timelock).map(|_| self.1.clone())
+    if self.0 <= timelock {
+      Some(self.1.clone())
+    } else {
+      None
+    }
   }
 
-  pub fn ignore_timelock(&self) -> Vec<SpendableOutput> {
+  #[must_use]
+  pub fn ignore_timelock(&self) -> Vec<O> {
     self.1.clone()
   }
 }
 
-impl SpendableOutput {
-  pub fn serialize(&self) -> Vec<u8> {
-    let mut res = Vec::with_capacity(32 + 1 + 32 + 32 + 40);
-    res.extend(&self.tx);
-    res.push(self.o);
-    res.extend(self.key.compress().to_bytes());
-    res.extend(self.key_offset.to_bytes());
-    res.extend(self.commitment.mask.to_bytes());
-    res.extend(self.commitment.amount.to_le_bytes());
-    res
-  }
+impl Scanner {
+  /// Scan a transaction to discover the received outputs.
+  pub fn scan_transaction(&mut self, tx: &Transaction) -> Timelocked<ReceivedOutput> {
+    // Only scan RCT TXs since we can only spend RCT outputs
+    if tx.prefix.version != 2 {
+      return Timelocked(tx.prefix.timelock, vec![]);
+    }
 
-  pub fn deserialize<R: std::io::Read>(r: &mut R) -> std::io::Result<SpendableOutput> {
-    Ok(
-      SpendableOutput {
-        tx: read_32(r)?,
-        o: { let mut o = [0; 1]; r.read_exact(&mut o)?; o[0] },
-        key: read_point(r)?,
-        key_offset: read_scalar(r)?,
-        commitment: Commitment::new(
-          read_scalar(r)?,
-          { let mut amount = [0; 8]; r.read_exact(&mut amount)?; u64::from_le_bytes(amount) }
-        )
-      }
-    )
-  }
-}
-
-impl Transaction {
-  pub fn scan(
-    &self,
-    view: ViewPair,
-    guaranteed: bool
-  ) -> Timelocked {
-    let mut extra = vec![];
-    write_varint(&u64::try_from(self.prefix.extra.len()).unwrap(), &mut extra).unwrap();
-    extra.extend(&self.prefix.extra);
-    let extra = deserialize::<ExtraField>(&extra);
-
-    let pubkeys: Vec<EdwardsPoint>;
-    if let Ok(extra) = extra {
-      let mut m_pubkeys = vec![];
-      if let Some(key) = extra.tx_pubkey() {
-        m_pubkeys.push(key);
-      }
-      if let Some(keys) = extra.tx_additional_pubkeys() {
-        m_pubkeys.extend(&keys);
-      }
-
-      pubkeys = m_pubkeys.iter().map(|key| key.point.decompress()).filter_map(|key| key).collect();
-    } else {
-      return Timelocked(self.prefix.timelock, vec![]);
+    let Ok(extra) = Extra::read::<&[u8]>(&mut tx.prefix.extra.as_ref()) else {
+      return Timelocked(tx.prefix.timelock, vec![]);
     };
 
+    let Some((tx_key, additional)) = extra.keys() else {
+      return Timelocked(tx.prefix.timelock, vec![]);
+    };
+
+    let payment_id = extra.payment_id();
+
     let mut res = vec![];
-    for (o, output) in self.prefix.outputs.iter().enumerate() {
-      // TODO: This may be replaceable by pubkeys[o]
-      for pubkey in &pubkeys {
-        let key_offset = shared_key(
-          Some(uniqueness(&self.prefix.inputs)).filter(|_| guaranteed),
-          view.view,
-          pubkey,
-          o
-        );
-        // P - shared == spend
-        if (output.key - (&key_offset * &ED25519_BASEPOINT_TABLE)) != view.spend {
+    for (o, output) in tx.prefix.outputs.iter().enumerate() {
+      // https://github.com/serai-dex/serai/issues/106
+      if let Some(burning_bug) = self.burning_bug.as_ref() {
+        if burning_bug.contains(&output.key) {
           continue;
         }
+      }
 
+      let output_key = output.key.decompress();
+      if output_key.is_none() {
+        continue;
+      }
+      let output_key = output_key.unwrap();
+
+      for key in [Some(Some(&tx_key)), additional.as_ref().map(|additional| additional.get(o))] {
+        let Some(Some(key)) = key else {
+          if key == Some(None) {
+            // This is non-standard. There were additional keys, yet not one for this output
+            // https://github.com/monero-project/monero/
+            //   blob/04a1e2875d6e35e27bb21497988a6c822d319c28/
+            //   src/cryptonote_basic/cryptonote_format_utils.cpp#L1062
+            // TODO: Should this return? Where does Monero set the trap handler for this exception?
+            continue;
+          } else {
+            break;
+          }
+        };
+        let (view_tag, shared_key, payment_id_xor) = shared_key(
+          if self.burning_bug.is_none() { Some(uniqueness(&tx.prefix.inputs)) } else { None },
+          self.pair.view.deref() * key,
+          o,
+        );
+
+        let payment_id =
+          if let Some(PaymentId::Encrypted(id)) = payment_id.map(|id| id ^ payment_id_xor) {
+            id
+          } else {
+            payment_id_xor
+          };
+
+        if let Some(actual_view_tag) = output.view_tag {
+          if actual_view_tag != view_tag {
+            continue;
+          }
+        }
+
+        // P - shared == spend
+        let subaddress = self
+          .subaddresses
+          .get(&(output_key - (&shared_key * &ED25519_BASEPOINT_TABLE)).compress());
+        if subaddress.is_none() {
+          continue;
+        }
+        let subaddress = *subaddress.unwrap();
+
+        // If it has torsion, it'll substract the non-torsioned shared key to a torsioned key
+        // We will not have a torsioned key in our HashMap of keys, so we wouldn't identify it as
+        // ours
+        // If we did though, it'd enable bypassing the included burning bug protection
+        assert!(output_key.is_torsion_free());
+
+        let mut key_offset = shared_key;
+        if let Some(subaddress) = subaddress {
+          key_offset += self.pair.subaddress_derivation(subaddress);
+        }
         // Since we've found an output to us, get its amount
         let mut commitment = Commitment::zero();
 
         // Miner transaction
-        if output.amount != 0 {
-          commitment.amount = output.amount;
+        if let Some(amount) = output.amount {
+          commitment.amount = amount;
         // Regular transaction
         } else {
-          let amount = match self.rct_signatures.base.ecdh_info.get(o) {
-            Some(amount) => amount_decryption(*amount, key_offset),
+          let (mask, amount) = match tx.rct_signatures.base.encrypted_amounts.get(o) {
+            Some(amount) => amount_decryption(amount, shared_key),
             // This should never happen, yet it may be possible with miner transactions?
             // Using get just decreases the possibility of a panic and lets us move on in that case
-            None => break
+            None => break,
           };
 
           // Rebuild the commitment to verify it
-          commitment = Commitment::new(commitment_mask(key_offset), amount);
+          commitment = Commitment::new(mask, amount);
           // If this is a malicious commitment, move to the next output
           // Any other R value will calculate to a different spend key and are therefore ignorable
-          if Some(&commitment.calculate()) != self.rct_signatures.base.commitments.get(o) {
+          if Some(&commitment.calculate()) != tx.rct_signatures.base.commitments.get(o) {
             break;
           }
         }
 
         if commitment.amount != 0 {
-          res.push(SpendableOutput {
-            tx: self.hash(),
-            o: o.try_into().unwrap(),
-            key: output.key,
-            key_offset,
-            commitment
+          res.push(ReceivedOutput {
+            absolute: AbsoluteId { tx: tx.hash(), o: o.try_into().unwrap() },
+
+            data: OutputData { key: output_key, key_offset, commitment },
+
+            metadata: Metadata { subaddress, payment_id, arbitrary_data: extra.data() },
           });
+
+          if let Some(burning_bug) = self.burning_bug.as_mut() {
+            burning_bug.insert(output.key);
+          }
         }
         // Break to prevent public keys from being included multiple times, triggering multiple
         // inclusions of the same output
@@ -156,6 +416,59 @@ impl Transaction {
       }
     }
 
-    Timelocked(self.prefix.timelock, res)
+    Timelocked(tx.prefix.timelock, res)
+  }
+
+  /// Scan a block to obtain its spendable outputs. Its the presence in a block giving these
+  /// transactions their global index, and this must be batched as asking for the index of specific
+  /// transactions is a dead giveaway for which transactions you successfully scanned. This
+  /// function obtains the output indexes for the miner transaction, incrementing from there
+  /// instead.
+  pub async fn scan<RPC: RpcConnection>(
+    &mut self,
+    rpc: &Rpc<RPC>,
+    block: &Block,
+  ) -> Result<Vec<Timelocked<SpendableOutput>>, RpcError> {
+    let mut index = rpc.get_o_indexes(block.miner_tx.hash()).await?[0];
+    let mut txs = vec![block.miner_tx.clone()];
+    txs.extend(rpc.get_transactions(&block.txs).await?);
+
+    let map = |mut timelock: Timelocked<ReceivedOutput>, index| {
+      if timelock.1.is_empty() {
+        None
+      } else {
+        Some(Timelocked(
+          timelock.0,
+          timelock
+            .1
+            .drain(..)
+            .map(|output| SpendableOutput {
+              global_index: index + u64::from(output.absolute.o),
+              output,
+            })
+            .collect(),
+        ))
+      }
+    };
+
+    let mut res = vec![];
+    for tx in txs {
+      if let Some(timelock) = map(self.scan_transaction(&tx), index) {
+        res.push(timelock);
+      }
+      index += u64::try_from(
+        tx.prefix
+          .outputs
+          .iter()
+          // Filter to v2 miner TX outputs/RCT outputs since we're tracking the RCT output index
+          .filter(|output| {
+            ((tx.prefix.version == 2) && matches!(tx.prefix.inputs.get(0), Some(Input::Gen(..)))) ||
+              output.amount.is_none()
+          })
+          .count(),
+      )
+      .unwrap()
+    }
+    Ok(res)
   }
 }

coins/monero/src/wallet/seed/classic.rs

@@ -0,0 +1,271 @@
+use core::ops::Deref;
+use std_shims::{
+  sync::OnceLock,
+  vec::Vec,
+  string::{String, ToString},
+  collections::HashMap,
+};
+
+use zeroize::{Zeroize, Zeroizing};
+use rand_core::{RngCore, CryptoRng};
+
+use crc::{Crc, CRC_32_ISO_HDLC};
+
+use curve25519_dalek::scalar::Scalar;
+
+use crate::{
+  random_scalar,
+  wallet::seed::{SeedError, Language},
+};
+
+pub(crate) const CLASSIC_SEED_LENGTH: usize = 24;
+pub(crate) const CLASSIC_SEED_LENGTH_WITH_CHECKSUM: usize = 25;
+
+fn trim(word: &str, len: usize) -> Zeroizing<String> {
+  Zeroizing::new(word.chars().take(len).collect())
+}
+
+struct WordList {
+  word_list: Vec<&'static str>,
+  word_map: HashMap<&'static str, usize>,
+  trimmed_word_map: HashMap<String, usize>,
+  unique_prefix_length: usize,
+}
+
+impl WordList {
+  fn new(word_list: Vec<&'static str>, prefix_length: usize) -> Self {
+    let mut lang = Self {
+      word_list,
+      word_map: HashMap::new(),
+      trimmed_word_map: HashMap::new(),
+      unique_prefix_length: prefix_length,
+    };
+
+    for (i, word) in lang.word_list.iter().enumerate() {
+      lang.word_map.insert(word, i);
+      lang.trimmed_word_map.insert(trim(word, lang.unique_prefix_length).deref().clone(), i);
+    }
+
+    lang
+  }
+}
+
+static LANGUAGES_CELL: OnceLock<HashMap<Language, WordList>> = OnceLock::new();
+#[allow(non_snake_case)]
+fn LANGUAGES() -> &'static HashMap<Language, WordList> {
+  LANGUAGES_CELL.get_or_init(|| {
+    HashMap::from([
+      (Language::Chinese, WordList::new(include!("./classic/zh.rs"), 1)),
+      (Language::English, WordList::new(include!("./classic/en.rs"), 3)),
+      (Language::Dutch, WordList::new(include!("./classic/nl.rs"), 4)),
+      (Language::French, WordList::new(include!("./classic/fr.rs"), 4)),
+      (Language::Spanish, WordList::new(include!("./classic/es.rs"), 4)),
+      (Language::German, WordList::new(include!("./classic/de.rs"), 4)),
+      (Language::Italian, WordList::new(include!("./classic/it.rs"), 4)),
+      (Language::Portuguese, WordList::new(include!("./classic/pt.rs"), 4)),
+      (Language::Japanese, WordList::new(include!("./classic/ja.rs"), 3)),
+      (Language::Russian, WordList::new(include!("./classic/ru.rs"), 4)),
+      (Language::Esperanto, WordList::new(include!("./classic/eo.rs"), 4)),
+      (Language::Lojban, WordList::new(include!("./classic/jbo.rs"), 4)),
+      (Language::EnglishOld, WordList::new(include!("./classic/ang.rs"), 4)),
+    ])
+  })
+}
+
+#[cfg(test)]
+pub(crate) fn trim_by_lang(word: &str, lang: Language) -> String {
+  if lang == Language::EnglishOld {
+    word.to_string()
+  } else {
+    word.chars().take(LANGUAGES()[&lang].unique_prefix_length).collect()
+  }
+}
+
+fn checksum_index(words: &[Zeroizing<String>], lang: &WordList) -> usize {
+  let mut trimmed_words = Zeroizing::new(String::new());
+  for w in words {
+    *trimmed_words += &trim(w, lang.unique_prefix_length);
+  }
+
+  let crc = Crc::<u32>::new(&CRC_32_ISO_HDLC);
+  let mut digest = crc.digest();
+  digest.update(trimmed_words.as_bytes());
+
+  usize::try_from(digest.finalize()).unwrap() % words.len()
+}
+
+// Convert a private key to a seed
+fn key_to_seed(lang: Language, key: Zeroizing<Scalar>) -> ClassicSeed {
+  let bytes = Zeroizing::new(key.to_bytes());
+
+  // get the language words
+  let words = &LANGUAGES()[&lang].word_list;
+  let list_len = u64::try_from(words.len()).unwrap();
+
+  // To store the found words & add the checksum word later.
+  let mut seed = Vec::with_capacity(25);
+
+  // convert to words
+  // 4 bytes -> 3 words. 8 digits base 16 -> 3 digits base 1626
+  let mut segment = [0; 4];
+  let mut indices = [0; 4];
+  for i in 0 .. 8 {
+    // convert first 4 byte to u32 & get the word indices
+    let start = i * 4;
+    // convert 4 byte to u32
+    segment.copy_from_slice(&bytes[start .. (start + 4)]);
+    // Actually convert to a u64 so we can add without overflowing
+    indices[0] = u64::from(u32::from_le_bytes(segment));
+    indices[1] = indices[0];
+    indices[0] /= list_len;
+    indices[2] = indices[0] + indices[1];
+    indices[0] /= list_len;
+    indices[3] = indices[0] + indices[2];
+
+    // append words to seed
+    for i in indices.iter().skip(1) {
+      let word = usize::try_from(i % list_len).unwrap();
+      seed.push(Zeroizing::new(words[word].to_string()));
+    }
+  }
+  segment.zeroize();
+  indices.zeroize();
+
+  // create a checksum word for all languages except old english
+  if lang != Language::EnglishOld {
+    let checksum = seed[checksum_index(&seed, &LANGUAGES()[&lang])].clone();
+    seed.push(checksum);
+  }
+
+  let mut res = Zeroizing::new(String::new());
+  for (i, word) in seed.iter().enumerate() {
+    if i != 0 {
+      *res += " ";
+    }
+    *res += word;
+  }
+  ClassicSeed(res)
+}
+
+// Convert a seed to bytes
+pub(crate) fn seed_to_bytes(words: &str) -> Result<(Language, Zeroizing<[u8; 32]>), SeedError> {
+  // get seed words
+  let words = words.split_whitespace().map(|w| Zeroizing::new(w.to_string())).collect::<Vec<_>>();
+  if (words.len() != CLASSIC_SEED_LENGTH) && (words.len() != CLASSIC_SEED_LENGTH_WITH_CHECKSUM) {
+    panic!("invalid seed passed to seed_to_bytes");
+  }
+
+  // find the language
+  let (matched_indices, lang_name, lang) = (|| {
+    let has_checksum = words.len() == CLASSIC_SEED_LENGTH_WITH_CHECKSUM;
+    let mut matched_indices = Zeroizing::new(vec![]);
+
+    // Iterate through all the languages
+    'language: for (lang_name, lang) in LANGUAGES().iter() {
+      matched_indices.zeroize();
+      matched_indices.clear();
+
+      // Iterate through all the words and see if they're all present
+      for word in &words {
+        let trimmed = trim(word, lang.unique_prefix_length);
+        let word = if has_checksum { &trimmed } else { word };
+
+        if let Some(index) = if has_checksum {
+          lang.trimmed_word_map.get(word.deref())
+        } else {
+          lang.word_map.get(&word.as_str())
+        } {
+          matched_indices.push(*index);
+        } else {
+          continue 'language;
+        }
+      }
+
+      if has_checksum {
+        if lang_name == &Language::EnglishOld {
+          Err(SeedError::EnglishOldWithChecksum)?;
+        }
+
+        // exclude the last word when calculating a checksum.
+        let last_word = words.last().unwrap().clone();
+        let checksum = words[checksum_index(&words[.. words.len() - 1], lang)].clone();
+
+        // check the trimmed checksum and trimmed last word line up
+        if trim(&checksum, lang.unique_prefix_length) != trim(&last_word, lang.unique_prefix_length)
+        {
+          Err(SeedError::InvalidChecksum)?;
+        }
+      }
+
+      return Ok((matched_indices, lang_name, lang));
+    }
+
+    Err(SeedError::UnknownLanguage)?
+  })()?;
+
+  // convert to bytes
+  let mut res = Zeroizing::new([0; 32]);
+  let mut indices = Zeroizing::new([0; 4]);
+  for i in 0 .. 8 {
+    // read 3 indices at a time
+    let i3 = i * 3;
+    indices[1] = matched_indices[i3];
+    indices[2] = matched_indices[i3 + 1];
+    indices[3] = matched_indices[i3 + 2];
+
+    let inner = |i| {
+      let mut base = (lang.word_list.len() - indices[i] + indices[i + 1]) % lang.word_list.len();
+      // Shift the index over
+      for _ in 0 .. i {
+        base *= lang.word_list.len();
+      }
+      base
+    };
+    // set the last index
+    indices[0] = indices[1] + inner(1) + inner(2);
+    if (indices[0] % lang.word_list.len()) != indices[1] {
+      Err(SeedError::InvalidSeed)?;
+    }
+
+    let pos = i * 4;
+    let mut bytes = u32::try_from(indices[0]).unwrap().to_le_bytes();
+    res[pos .. (pos + 4)].copy_from_slice(&bytes);
+    bytes.zeroize();
+  }
+
+  Ok((*lang_name, res))
+}
+
+#[derive(Clone, PartialEq, Eq, Zeroize)]
+pub struct ClassicSeed(Zeroizing<String>);
+impl ClassicSeed {
+  pub(crate) fn new<R: RngCore + CryptoRng>(rng: &mut R, lang: Language) -> Self {
+    key_to_seed(lang, Zeroizing::new(random_scalar(rng)))
+  }
+
+  pub fn from_string(words: Zeroizing<String>) -> Result<Self, SeedError> {
+    let (lang, entropy) = seed_to_bytes(&words)?;
+
+    // Make sure this is a valid scalar
+    let mut scalar = Scalar::from_canonical_bytes(*entropy);
+    if scalar.is_none() {
+      Err(SeedError::InvalidSeed)?;
+    }
+    scalar.zeroize();
+
+    // Call from_entropy so a trimmed seed becomes a full seed
+    Ok(Self::from_entropy(lang, entropy).unwrap())
+  }
+
+  pub fn from_entropy(lang: Language, entropy: Zeroizing<[u8; 32]>) -> Option<Self> {
+    Scalar::from_canonical_bytes(*entropy).map(|scalar| key_to_seed(lang, Zeroizing::new(scalar)))
+  }
+
+  pub(crate) fn to_string(&self) -> Zeroizing<String> {
+    self.0.clone()
+  }
+
+  pub(crate) fn entropy(&self) -> Zeroizing<[u8; 32]> {
+    seed_to_bytes(&self.0).unwrap().1
+  }
+}