Merge branch 'develop' into next

This resolves the conflicts and gets the workspace `Cargo.toml`s to not be
invalid. It doesn't actually get clippy to pass again yet.

Does move `crypto/dkg/src/evrf` into a new `crypto/dkg/evrf` crate (which does
not yet compile).

.github/actions/bitcoin/action.yml

@@ -12,7 +12,7 @@ runs:
   steps:
     - name: Bitcoin Daemon Cache
       id: cache-bitcoind
-      uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2
+      uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809
       with:
         path: bitcoin.tar.gz
         key: bitcoind-${{ runner.os }}-${{ runner.arch }}-${{ inputs.version }}

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

@@ -7,13 +7,15 @@ runs:
     - name: Remove unused packages
       shell: bash
       run: |
-        sudo apt remove -y "*msbuild*" "*powershell*" "*nuget*" "*bazel*" "*ansible*" "*terraform*" "*heroku*" "*aws*" azure-cli
+        sudo apt remove -y "*powershell*" "*nuget*" "*bazel*" "*ansible*" "*terraform*" "*heroku*" "*aws*" azure-cli
         sudo apt remove -y "*nodejs*" "*npm*" "*yarn*" "*java*" "*kotlin*" "*golang*" "*swift*" "*julia*" "*fortran*" "*android*"
         sudo apt remove -y "*apache2*" "*nginx*" "*firefox*" "*chromium*" "*chrome*" "*edge*"
+
+        sudo apt remove -y --allow-remove-essential -f shim-signed *python3*
+        # This removal command requires the prior removals due to unmet dependencies otherwise
         sudo apt remove -y "*qemu*" "*sql*" "*texinfo*" "*imagemagick*"
-        sudo apt autoremove -y
-        sudo apt clean
-        docker system prune -a --volumes
+        # Reinstall python3 as a general dependency of a functional operating system
+        sudo apt install python3
       if: runner.os == 'Linux'
 
     - name: Remove unused packages
@@ -41,9 +43,34 @@ runs:
     - name: Install solc
       shell: bash
       run: |
-        cargo install svm-rs
+        cargo +1.89 install svm-rs --version =0.5.18
         svm install 0.8.26
         svm use 0.8.26
 
+    - name: Remove preinstalled Docker
+      shell: bash
+      run: |
+        docker system prune -a --volumes
+        sudo apt remove -y *docker*
+        # Install uidmap which will be required for the explicitly installed Docker
+        sudo apt install uidmap
+      if: runner.os == 'Linux'
+
+    - name: Update system dependencies
+      shell: bash
+      run: |
+        sudo apt update -y
+        sudo apt upgrade -y
+        sudo apt autoremove -y
+        sudo apt clean
+      if: runner.os == 'Linux'
+
+    - name: Install rootless Docker
+      uses: docker/setup-docker-action@b60f85385d03ac8acfca6d9996982511d8620a19
+      with:
+        rootless: true
+        set-host: true
+      if: runner.os == 'Linux'
+
     # - name: Cache Rust
     #   uses: Swatinem/rust-cache@a95ba195448af2da9b00fb742d14ffaaf3c21f43

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

@@ -12,7 +12,7 @@ runs:
   steps:
     - name: Monero Wallet RPC Cache
       id: cache-monero-wallet-rpc
-      uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2
+      uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809
       with:
         path: monero-wallet-rpc
         key: monero-wallet-rpc-${{ runner.os }}-${{ runner.arch }}-${{ inputs.version }}

.github/actions/monero/action.yml

@@ -12,7 +12,7 @@ runs:
   steps:
     - name: Monero Daemon Cache
       id: cache-monerod
-      uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2
+      uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809
       with:
         path: /usr/bin/monerod
         key: monerod-${{ runner.os }}-${{ runner.arch }}-${{ inputs.version }}

.github/nightly-version

@@ -1 +1 @@
-nightly-2025-02-01
+nightly-2025-08-01

.github/workflows/crypto-tests.yml

@@ -32,6 +32,7 @@ jobs:
             -p dalek-ff-group \
             -p minimal-ed448 \
             -p ciphersuite \
+            -p ciphersuite-kp256 \
             -p multiexp \
             -p schnorr-signatures \
             -p dleq \
@@ -40,5 +41,11 @@ jobs:
             -p ec-divisors \
             -p generalized-bulletproofs-ec-gadgets \
             -p dkg \
+            -p dkg-recovery \
+            -p dkg-dealer \
+            -p dkg-promote \
+            -p dkg-musig \
+            -p dkg-pedpop \
+            -p dkg-evrf \
             -p modular-frost \
             -p frost-schnorrkel

.github/workflows/daily-deny.yml

@@ -12,13 +12,13 @@ jobs:
       - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac
 
       - name: Advisory Cache
-        uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2
+        uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809
         with:
           path: ~/.cargo/advisory-db
           key: rust-advisory-db
 
       - name: Install cargo deny
-        run: cargo install --locked cargo-deny
+        run: cargo +1.89 install cargo-deny --version =0.18.3
 
       - name: Run cargo deny
-        run: cargo deny -L error --all-features check
+        run: cargo deny -L error --all-features check --hide-inclusion-graph

.github/workflows/lint.yml

@@ -26,7 +26,7 @@ jobs:
         uses: ./.github/actions/build-dependencies
 
       - name: Install nightly rust
-        run: rustup toolchain install ${{ steps.nightly.outputs.version }} --profile minimal -t wasm32-unknown-unknown -c clippy
+        run: rustup toolchain install ${{ steps.nightly.outputs.version }} --profile minimal -t wasm32v1-none -c rust-src -c clippy
 
       - name: Run Clippy
         run: cargo +${{ steps.nightly.outputs.version }} clippy --all-features --all-targets -- -D warnings -A clippy::items_after_test_module
@@ -46,16 +46,16 @@ jobs:
       - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac
 
       - name: Advisory Cache
-        uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2
+        uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809
         with:
           path: ~/.cargo/advisory-db
           key: rust-advisory-db
 
       - name: Install cargo deny
-        run: cargo install --locked cargo-deny
+        run: cargo +1.89 install cargo-deny --version =0.18.3
 
       - name: Run cargo deny
-        run: cargo deny -L error --all-features check
+        run: cargo deny -L error --all-features check --hide-inclusion-graph
 
   fmt:
     runs-on: ubuntu-latest
@@ -88,8 +88,8 @@ jobs:
       - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac
       - name: Verify all dependencies are in use
         run: |
-          cargo install cargo-machete
-          cargo machete
+          cargo +1.89 install cargo-machete --version =0.8.0
+          cargo +1.89 machete
 
   slither:
     runs-on: ubuntu-latest

.github/workflows/monero-tests.yaml

@@ -1,72 +0,0 @@
-name: Monero Tests
-
-on:
-  push:
-    branches:
-      - develop
-    paths:
-      - "networks/monero/**"
-      - "processor/**"
-
-  pull_request:
-    paths:
-      - "networks/monero/**"
-      - "processor/**"
-
-  workflow_dispatch:
-
-jobs:
-  # Only run these once since they will be consistent regardless of any node
-  unit-tests:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac
-
-      - name: Test Dependencies
-        uses: ./.github/actions/test-dependencies
-
-      - name: Run Unit Tests Without Features
-        run: |
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-io --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-generators --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-primitives --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-mlsag --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-clsag --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-borromean --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-bulletproofs --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-serai --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-rpc --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-simple-request-rpc --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-address --lib
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-wallet --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, v0.18.3.4]
-
-    steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac
-
-      - name: Test Dependencies
-        uses: ./.github/actions/test-dependencies
-        with:
-          monero-version: ${{ matrix.version }}
-
-      - name: Run Integration Tests Without Features
-        run: |
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-serai --test '*'
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-simple-request-rpc --test '*'
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-wallet --test '*'
-
-      - name: Run Integration Tests
-        # Don't run if the the tests workflow also will
-        if: ${{ matrix.version != 'v0.18.3.4' }}
-        run: |
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-serai --all-features --test '*'
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-simple-request-rpc --test '*'
-          GITHUB_CI=true RUST_BACKTRACE=1 cargo test --package monero-wallet --all-features --test '*'

.github/workflows/networks-tests.yml

@@ -34,16 +34,3 @@ jobs:
             -p ethereum-schnorr-contract \
             -p alloy-simple-request-transport \
             -p serai-ethereum-relayer \
-            -p monero-io \
-            -p monero-generators \
-            -p monero-primitives \
-            -p monero-mlsag \
-            -p monero-clsag \
-            -p monero-borromean \
-            -p monero-bulletproofs \
-            -p monero-serai \
-            -p monero-rpc \
-            -p monero-simple-request-rpc \
-            -p monero-address \
-            -p monero-wallet \
-            -p monero-serai-verify-chain

.github/workflows/pages.yml

@@ -69,7 +69,7 @@ jobs:
         uses: ./.github/actions/build-dependencies
       - name: Buld Rust docs
         run: |
-          rustup toolchain install ${{ steps.nightly.outputs.version }} --profile minimal -t wasm32-unknown-unknown -c rust-docs
+          rustup toolchain install ${{ steps.nightly.outputs.version }} --profile minimal -t wasm32v1-none -c rust-docs
           RUSTDOCFLAGS="--cfg docsrs" cargo +${{ steps.nightly.outputs.version }} doc --workspace --all-features
           mv target/doc docs/_site/rust
 

Cargo.toml

@@ -29,6 +29,7 @@ members = [
   "crypto/dalek-ff-group",
   "crypto/ed448",
   "crypto/ciphersuite",
+  "crypto/ciphersuite/kp256",
 
   "crypto/multiexp",
   "crypto/schnorr",
@@ -36,12 +37,14 @@ members = [
 
   "crypto/evrf/secq256k1",
   "crypto/evrf/embedwards25519",
-  "crypto/evrf/generalized-bulletproofs",
-  "crypto/evrf/circuit-abstraction",
-  "crypto/evrf/divisors",
-  "crypto/evrf/ec-gadgets",
 
   "crypto/dkg",
+  "crypto/dkg/recovery",
+  "crypto/dkg/dealer",
+  "crypto/dkg/promote",
+  "crypto/dkg/musig",
+  "crypto/dkg/pedpop",
+  "crypto/dkg/evrf",
   "crypto/frost",
   "crypto/schnorrkel",
 
@@ -52,20 +55,6 @@ members = [
   "networks/ethereum/alloy-simple-request-transport",
   "networks/ethereum/relayer",
 
-  "networks/monero/io",
-  "networks/monero/generators",
-  "networks/monero/primitives",
-  "networks/monero/ringct/mlsag",
-  "networks/monero/ringct/clsag",
-  "networks/monero/ringct/borromean",
-  "networks/monero/ringct/bulletproofs",
-  "networks/monero",
-  "networks/monero/rpc",
-  "networks/monero/rpc/simple-request",
-  "networks/monero/wallet/address",
-  "networks/monero/wallet",
-  "networks/monero/verify-chain",
-
   "message-queue",
 
   "processor/messages",
@@ -167,21 +156,29 @@ secq256k1 = { opt-level = 3 }
 embedwards25519 = { opt-level = 3 }
 generalized-bulletproofs = { opt-level = 3 }
 generalized-bulletproofs-circuit-abstraction = { opt-level = 3 }
-ec-divisors = { opt-level = 3 }
 generalized-bulletproofs-ec-gadgets = { opt-level = 3 }
 
-dkg = { opt-level = 3 }
-
 monero-generators = { opt-level = 3 }
 monero-borromean = { opt-level = 3 }
 monero-bulletproofs = { opt-level = 3 }
 monero-mlsag = { opt-level = 3 }
 monero-clsag = { opt-level = 3 }
+monero-oxide = { opt-level = 3 }
 
 [profile.release]
 panic = "unwind"
+overflow-checks = true
 
 [patch.crates-io]
+# Dependencies from monero-oxide which originate from within our own tree
+std-shims = { path = "common/std-shims" }
+simple-request = { path = "common/request" }
+multiexp = { path = "crypto/multiexp" }
+flexible-transcript = { path = "crypto/transcript" }
+dalek-ff-group = { path = "crypto/dalek-ff-group" }
+minimal-ed448 = { path = "crypto/ed448" }
+modular-frost = { path = "crypto/frost" }
+
 # https://github.com/rust-lang-nursery/lazy-static.rs/issues/201
 lazy_static = { git = "https://github.com/rust-lang-nursery/lazy-static.rs", rev = "5735630d46572f1e5377c8f2ba0f79d18f53b10c" }
 
@@ -209,6 +206,8 @@ directories-next = { path = "patches/directories-next" }
 unwrap_or_default = "allow"
 map_unwrap_or = "allow"
 needless_continue = "allow"
+manual_is_multiple_of = "allow"
+incompatible_msrv = "allow" # Manually verified with a GitHub workflow
 borrow_as_ptr = "deny"
 cast_lossless = "deny"
 cast_possible_truncation = "deny"

README.md

@@ -59,7 +59,6 @@ issued at the discretion of the Immunefi program managers.
 - [Website](https://serai.exchange/): https://serai.exchange/
 - [Immunefi](https://immunefi.com/bounty/serai/): https://immunefi.com/bounty/serai/
 - [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
 - [Reddit](https://www.reddit.com/r/SeraiDEX/): https://www.reddit.com/r/SeraiDEX/

common/request/Cargo.toml

@@ -7,7 +7,7 @@ repository = "https://github.com/serai-dex/serai/tree/develop/common/simple-requ
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["http", "https", "async", "request", "ssl"]
 edition = "2021"
-rust-version = "1.71"
+rust-version = "1.70"
 
 [package.metadata.docs.rs]
 all-features = true

common/std-shims/Cargo.toml

@@ -1,13 +1,13 @@
 [package]
 name = "std-shims"
-version = "0.1.1"
+version = "0.1.4"
 description = "A series of std shims to make alloc more feasible"
 license = "MIT"
 repository = "https://github.com/serai-dex/serai/tree/develop/common/std-shims"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["nostd", "no_std", "alloc", "io"]
 edition = "2021"
-rust-version = "1.80"
+rust-version = "1.64"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -17,7 +17,8 @@ rustdoc-args = ["--cfg", "docsrs"]
 workspace = true
 
 [dependencies]
-spin = { version = "0.9", default-features = false, features = ["use_ticket_mutex", "lazy"] }
+rustversion = { version = "1", default-features = false }
+spin = { version = "0.10", default-features = false, features = ["use_ticket_mutex", "once", "lazy"] }
 hashbrown = { version = "0.15", default-features = false, features = ["default-hasher", "inline-more"] }
 
 [features]

common/std-shims/README.md

@@ -3,4 +3,9 @@
 A crate which passes through to std when the default `std` feature is enabled,
 yet provides a series of shims when it isn't.
 
-`HashSet` and `HashMap` are provided via `hashbrown`.
+No guarantee of one-to-one parity is provided. The shims provided aim to be sufficient for the
+average case.
+
+`HashSet` and `HashMap` are provided via `hashbrown`. Synchronization primitives are provided via
+`spin` (avoiding a requirement on `critical-section`).
+types are not guaranteed to be

common/std-shims/src/lib.rs

@@ -11,3 +11,64 @@ pub mod io;
 pub use alloc::vec;
 pub use alloc::str;
 pub use alloc::string;
+
+pub mod prelude {
+  #[rustversion::before(1.73)]
+  #[doc(hidden)]
+  pub trait StdShimsDivCeil {
+    fn div_ceil(self, rhs: Self) -> Self;
+  }
+  #[rustversion::before(1.73)]
+  mod impl_divceil {
+    use super::StdShimsDivCeil;
+    impl StdShimsDivCeil for u8 {
+      fn div_ceil(self, rhs: Self) -> Self {
+        (self + (rhs - 1)) / rhs
+      }
+    }
+    impl StdShimsDivCeil for u16 {
+      fn div_ceil(self, rhs: Self) -> Self {
+        (self + (rhs - 1)) / rhs
+      }
+    }
+    impl StdShimsDivCeil for u32 {
+      fn div_ceil(self, rhs: Self) -> Self {
+        (self + (rhs - 1)) / rhs
+      }
+    }
+    impl StdShimsDivCeil for u64 {
+      fn div_ceil(self, rhs: Self) -> Self {
+        (self + (rhs - 1)) / rhs
+      }
+    }
+    impl StdShimsDivCeil for u128 {
+      fn div_ceil(self, rhs: Self) -> Self {
+        (self + (rhs - 1)) / rhs
+      }
+    }
+    impl StdShimsDivCeil for usize {
+      fn div_ceil(self, rhs: Self) -> Self {
+        (self + (rhs - 1)) / rhs
+      }
+    }
+  }
+
+  #[cfg(feature = "std")]
+  #[rustversion::before(1.74)]
+  #[doc(hidden)]
+  pub trait StdShimsIoErrorOther {
+    fn other<E>(error: E) -> Self
+    where
+      E: Into<Box<dyn std::error::Error + Send + Sync>>;
+  }
+  #[cfg(feature = "std")]
+  #[rustversion::before(1.74)]
+  impl StdShimsIoErrorOther for std::io::Error {
+    fn other<E>(error: E) -> Self
+    where
+      E: Into<Box<dyn std::error::Error + Send + Sync>>,
+    {
+      std::io::Error::new(std::io::ErrorKind::Other, error)
+    }
+  }
+}

common/std-shims/src/sync.rs

@@ -25,7 +25,11 @@ mod mutex_shim {
 }
 pub use mutex_shim::{ShimMutex as Mutex, MutexGuard};
 
-#[cfg(feature = "std")]
-pub use std::sync::LazyLock;
 #[cfg(not(feature = "std"))]
 pub use spin::Lazy as LazyLock;
+#[rustversion::before(1.80)]
+#[cfg(feature = "std")]
+pub use spin::Lazy as LazyLock;
+#[rustversion::since(1.80)]
+#[cfg(feature = "std")]
+pub use std::sync::LazyLock;

coordinator/Cargo.toml

@@ -25,8 +25,12 @@ rand_core = { version = "0.6", default-features = false, features = ["std"] }
 blake2 = { version = "0.10", default-features = false, features = ["std"] }
 schnorrkel = { version = "0.11", default-features = false, features = ["std"] }
 
-ciphersuite = { path = "../crypto/ciphersuite", default-features = false, features = ["std", "ristretto"] }
-dkg = { path = "../crypto/dkg", default-features = false, features = ["std"] }
+transcript = { package = "flexible-transcript", path = "../crypto/transcript", default-features = false, features = ["std", "recommended"] }
+dalek-ff-group = { path = "../crypto/dalek-ff-group", default-features = false, features = ["std"] }
+ciphersuite = { path = "../crypto/ciphersuite", default-features = false, features = ["std"] }
+schnorr = { package = "schnorr-signatures", path = "../crypto/schnorr", default-features = false, features = ["std", "aggregate"] }
+dkg-musig = { path = "../crypto/dkg/musig", default-features = false, features = ["std"] }
+frost = { package = "modular-frost", path = "../crypto/frost" }
 frost-schnorrkel = { path = "../crypto/schnorrkel" }
 
 hex = { version = "0.4", default-features = false, features = ["std"] }

coordinator/src/main.rs

@@ -4,9 +4,13 @@ use std::{sync::Arc, collections::HashMap, time::Instant};
 use zeroize::{Zeroize, Zeroizing};
 use rand_core::{RngCore, OsRng};
 
+use dalek_ff_group::Ristretto;
 use ciphersuite::{
-  group::{ff::PrimeField, GroupEncoding},
-  Ciphersuite, Ristretto,
+  group::{
+    ff::{Field, PrimeField},
+    GroupEncoding,
+  },
+  Ciphersuite,
 };
 
 use borsh::BorshDeserialize;

coordinator/tributary-sdk/Cargo.toml

@@ -27,8 +27,8 @@ rand_chacha = { version = "0.3", default-features = false, features = ["std"] }
 blake2 = { version = "0.10", default-features = false, features = ["std"] }
 transcript = { package = "flexible-transcript", path = "../../crypto/transcript", version = "0.3", default-features = false, features = ["std", "recommended"] }
 
-ciphersuite = { package = "ciphersuite", path = "../../crypto/ciphersuite", version = "0.4", default-features = false, features = ["std", "ristretto"] }
-schnorr = { package = "schnorr-signatures", path = "../../crypto/schnorr", version = "0.5", default-features = false, features = ["std"] }
+ciphersuite = { package = "ciphersuite", path = "../../crypto/ciphersuite", version = "0.4", default-features = false, features = ["std"] }
+schnorr = { package = "schnorr-signatures", path = "../../crypto/schnorr", version = "0.5", default-features = false, features = ["std", "aggregate"] }
 
 hex = { version = "0.4", default-features = false, features = ["std"] }
 log = { version = "0.4", default-features = false, features = ["std"] }

coordinator/tributary-sdk/src/blockchain.rs

@@ -1,6 +1,7 @@
 use std::collections::{VecDeque, HashSet};
 
-use ciphersuite::{group::GroupEncoding, Ciphersuite, Ristretto};
+use dalek_ff_group::Ristretto;
+use ciphersuite::{group::GroupEncoding, Ciphersuite};
 
 use serai_db::{Get, DbTxn, Db};
 

coordinator/tributary-sdk/src/mempool.rs

@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 
-use ciphersuite::{Ciphersuite, Ristretto};
+use dalek_ff_group::Ristretto;
+use ciphersuite::Ciphersuite;
 
 use serai_db::{DbTxn, Db};
 

coordinator/tributary-sdk/src/tendermint/mod.rs

@@ -9,12 +9,13 @@ use rand_chacha::ChaCha12Rng;
 
 use transcript::{Transcript, RecommendedTranscript};
 
+use dalek_ff_group::Ristretto;
 use ciphersuite::{
   group::{
     GroupEncoding,
     ff::{Field, PrimeField},
   },
-  Ciphersuite, Ristretto,
+  Ciphersuite,
 };
 use schnorr::{
   SchnorrSignature,

coordinator/tributary-sdk/src/tendermint/tx.rs

@@ -4,7 +4,8 @@ use scale::{Encode, Decode, IoReader};
 
 use blake2::{Digest, Blake2s256};
 
-use ciphersuite::{Ciphersuite, Ristretto};
+use dalek_ff_group::Ristretto;
+use ciphersuite::Ciphersuite;
 
 use crate::{
   transaction::{Transaction, TransactionKind, TransactionError},

coordinator/tributary-sdk/src/tests/block.rs

@@ -1,9 +1,11 @@
 use std::{sync::Arc, io, collections::HashMap, fmt::Debug};
 
 use blake2::{Digest, Blake2s256};
+
+use dalek_ff_group::Ristretto;
 use ciphersuite::{
   group::{ff::Field, Group},
-  Ciphersuite, Ristretto,
+  Ciphersuite,
 };
 use schnorr::SchnorrSignature;
 

coordinator/tributary-sdk/src/tests/blockchain.rs

@@ -10,7 +10,8 @@ use rand::rngs::OsRng;
 
 use blake2::{Digest, Blake2s256};
 
-use ciphersuite::{group::ff::Field, Ciphersuite, Ristretto};
+use dalek_ff_group::Ristretto;
+use ciphersuite::{group::ff::Field, Ciphersuite};
 
 use serai_db::{DbTxn, Db, MemDb};
 

coordinator/tributary-sdk/src/tests/mempool.rs

@@ -3,7 +3,8 @@ use std::{sync::Arc, collections::HashMap};
 use zeroize::Zeroizing;
 use rand::{RngCore, rngs::OsRng};
 
-use ciphersuite::{group::ff::Field, Ciphersuite, Ristretto};
+use dalek_ff_group::Ristretto;
+use ciphersuite::{group::ff::Field, Ciphersuite};
 
 use tendermint::ext::Commit;
 

coordinator/tributary-sdk/src/tests/transaction/mod.rs

@@ -6,9 +6,10 @@ use rand::{RngCore, CryptoRng, rngs::OsRng};
 
 use blake2::{Digest, Blake2s256};
 
+use dalek_ff_group::Ristretto;
 use ciphersuite::{
   group::{ff::Field, Group},
-  Ciphersuite, Ristretto,
+  Ciphersuite,
 };
 use schnorr::SchnorrSignature;
 

coordinator/tributary-sdk/src/tests/transaction/signed.rs

@@ -2,7 +2,8 @@ use rand::rngs::OsRng;
 
 use blake2::{Digest, Blake2s256};
 
-use ciphersuite::{group::ff::Field, Ciphersuite, Ristretto};
+use dalek_ff_group::Ristretto;
+use ciphersuite::{group::ff::Field, Ciphersuite};
 
 use crate::{
   ReadWrite,

coordinator/tributary-sdk/src/tests/transaction/tendermint.rs

@@ -3,7 +3,8 @@ use std::sync::Arc;
 use zeroize::Zeroizing;
 use rand::{RngCore, rngs::OsRng};
 
-use ciphersuite::{Ristretto, Ciphersuite, group::ff::Field};
+use dalek_ff_group::Ristretto;
+use ciphersuite::{Ciphersuite, group::ff::Field};
 
 use scale::Encode;
 

coordinator/tributary/src/transaction.rs

@@ -5,9 +5,10 @@ use zeroize::Zeroizing;
 use rand_core::{RngCore, CryptoRng};
 
 use blake2::{digest::typenum::U32, Digest, Blake2b};
+use dalek_ff_group::Ristretto;
 use ciphersuite::{
-  group::{ff::Field, Group, GroupEncoding},
-  Ciphersuite, Ristretto,
+  group::{Group, GroupEncoding},
+  Ciphersuite,
 };
 use schnorr::SchnorrSignature;
 

crypto/ciphersuite/Cargo.toml

@@ -1,13 +1,13 @@
 [package]
 name = "ciphersuite"
-version = "0.4.1"
+version = "0.4.2"
 description = "Ciphersuites built around ff/group"
 license = "MIT"
 repository = "https://github.com/serai-dex/serai/tree/develop/crypto/ciphersuite"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["ciphersuite", "ff", "group"]
 edition = "2021"
-rust-version = "1.80"
+rust-version = "1.66"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -24,22 +24,12 @@ rand_core = { version = "0.6", default-features = false }
 zeroize = { version = "^1.5", default-features = false, features = ["derive"] }
 subtle = { version = "^2.4", default-features = false }
 
-digest = { version = "0.10", default-features = false }
+digest = { version = "0.10", default-features = false, features = ["core-api"] }
 transcript = { package = "flexible-transcript", path = "../transcript", version = "^0.3.2", default-features = false }
-sha2 = { version = "0.10", default-features = false, optional = true }
-sha3 = { version = "0.10", default-features = false, optional = true }
 
 ff = { version = "0.13", default-features = false, features = ["bits"] }
 group = { version = "0.13", default-features = false }
 
-dalek-ff-group = { path = "../dalek-ff-group", version = "0.4", default-features = false, optional = true }
-
-elliptic-curve = { version = "0.13", default-features = false, features = ["hash2curve"], optional = true }
-p256 = { version = "^0.13.1", default-features = false, features = ["arithmetic", "bits", "hash2curve"], optional = true }
-k256 = { version = "^0.13.1", default-features = false, features = ["arithmetic", "bits", "hash2curve"], optional = true }
-
-minimal-ed448 = { path = "../ed448", version = "0.4", default-features = false, optional = true }
-
 [dev-dependencies]
 hex = { version = "0.4", default-features = false, features = ["std"] }
 
@@ -59,27 +49,8 @@ std = [
 
   "digest/std",
   "transcript/std",
-  "sha2?/std",
-  "sha3?/std",
 
   "ff/std",
-
-  "dalek-ff-group?/std",
-
-  "elliptic-curve?/std",
-  "p256?/std",
-  "k256?/std",
-  "minimal-ed448?/std",
 ]
 
-dalek = ["sha2", "dalek-ff-group"]
-ed25519 = ["dalek"]
-ristretto = ["dalek"]
-
-kp256 = ["sha2", "elliptic-curve"]
-p256 = ["kp256", "dep:p256"]
-secp256k1 = ["kp256", "k256"]
-
-ed448 = ["sha3", "minimal-ed448"]
-
 default = ["std"]

crypto/ciphersuite/README.md

@@ -21,6 +21,8 @@ Their `hash_to_F` is the
 [IETF's hash to curve](https://www.ietf.org/archive/id/draft-irtf-cfrg-hash-to-curve-16.html),
 yet applied to their scalar field.
 
+Please see the [`ciphersuite-kp256`](https://docs.rs/ciphersuite-kp256) crate for more info.
+
 ### Ed25519/Ristretto
 
 Ed25519/Ristretto are offered via
@@ -33,6 +35,8 @@ the draft
 [RFC-RISTRETTO](https://www.ietf.org/archive/id/draft-irtf-cfrg-ristretto255-decaf448-05.html).
 The domain-separation tag is naively prefixed to the message.
 
+Please see the [`dalek-ff-group`](https://docs.rs/dalek-ff-group) crate for more info.
+
 ### Ed448
 
 Ed448 is offered via [minimal-ed448](https://crates.io/crates/minimal-ed448), an
@@ -42,3 +46,5 @@ to its prime-order subgroup.
 Its `hash_to_F` is the wide reduction of SHAKE256, with a 114-byte output, as
 used in [RFC-8032](https://www.rfc-editor.org/rfc/rfc8032). The
 domain-separation tag is naively prefixed to the message.
+
+Please see the [`minimal-ed448`](https://docs.rs/minimal-ed448) crate for more info.

crypto/ciphersuite/kp256/Cargo.toml

@@ -0,0 +1,55 @@
+[package]
+name = "ciphersuite-kp256"
+version = "0.4.0"
+description = "Ciphersuites built around ff/group"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/crypto/ciphersuite/kp256"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+keywords = ["ciphersuite", "ff", "group"]
+edition = "2021"
+rust-version = "1.66"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+rand_core = { version = "0.6", default-features = false }
+
+zeroize = { version = "^1.5", default-features = false, features = ["derive"] }
+
+sha2 = { version = "0.10", default-features = false }
+
+elliptic-curve = { version = "0.13", default-features = false, features = ["hash2curve"] }
+p256 = { version = "^0.13.1", default-features = false, features = ["arithmetic", "bits", "hash2curve"] }
+k256 = { version = "^0.13.1", default-features = false, features = ["arithmetic", "bits", "hash2curve"] }
+
+ciphersuite = { path = "../", version = "0.4", default-features = false }
+
+[dev-dependencies]
+hex = { version = "0.4", default-features = false, features = ["std"] }
+
+rand_core = { version = "0.6", default-features = false, features = ["std"] }
+
+ff-group-tests = { version = "0.13", path = "../../ff-group-tests" }
+
+[features]
+alloc = ["ciphersuite/alloc"]
+std = [
+  "rand_core/std",
+
+  "zeroize/std",
+
+  "sha2/std",
+
+  "elliptic-curve/std",
+  "p256/std",
+  "k256/std",
+
+  "ciphersuite/std",
+]
+
+default = ["std"]

crypto/ciphersuite/kp256/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2023-2024 Luke Parker
+Copyright (c) 2021-2023 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

crypto/ciphersuite/kp256/README.md

@@ -0,0 +1,3 @@
+# Ciphersuite {k, p}256
+
+SECP256k1 and P-256 Ciphersuites around k256 and p256.

crypto/ciphersuite/kp256/src/lib.rs

@@ -1,16 +1,17 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![cfg_attr(not(feature = "std"), no_std)]
+
 use zeroize::Zeroize;
 
 use sha2::Sha256;
 
-use group::ff::PrimeField;
-
 use elliptic_curve::{
   generic_array::GenericArray,
-  bigint::{NonZero, CheckedAdd, Encoding, U384, U512},
+  bigint::{NonZero, CheckedAdd, Encoding, U384},
   hash2curve::{Expander, ExpandMsg, ExpandMsgXmd},
 };
 
-use crate::Ciphersuite;
+use ciphersuite::{group::ff::PrimeField, Ciphersuite};
 
 macro_rules! kp_curve {
   (
@@ -31,22 +32,6 @@ macro_rules! kp_curve {
         $lib::ProjectivePoint::GENERATOR
       }
 
-      fn reduce_512(scalar: [u8; 64]) -> Self::F {
-        let mut modulus = [0; 64];
-        modulus[32 ..].copy_from_slice(&(Self::F::ZERO - Self::F::ONE).to_bytes());
-        let modulus = U512::from_be_slice(&modulus).checked_add(&U512::ONE).unwrap();
-
-        let mut wide =
-          U512::from_be_bytes(scalar).rem(&NonZero::new(modulus).unwrap()).to_be_bytes();
-
-        let mut array = *GenericArray::from_slice(&wide[32 ..]);
-        let res = $lib::Scalar::from_repr(array).unwrap();
-
-        wide.zeroize();
-        array.zeroize();
-        res
-      }
-
       fn hash_to_F(dst: &[u8], msg: &[u8]) -> Self::F {
         // While one of these two libraries does support directly hashing to the Scalar field, the
         // other doesn't. While that's probably an oversight, this is a universally working method
@@ -123,12 +108,9 @@ fn test_oversize_dst<C: Ciphersuite>() {
 /// Ciphersuite for Secp256k1.
 ///
 /// hash_to_F is implemented via the IETF draft for hash to curve's hash_to_field (v16).
-#[cfg(feature = "secp256k1")]
 #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
 pub struct Secp256k1;
-#[cfg(feature = "secp256k1")]
 kp_curve!("secp256k1", k256, Secp256k1, b"secp256k1");
-#[cfg(feature = "secp256k1")]
 #[test]
 fn test_secp256k1() {
   ff_group_tests::group::test_prime_group_bits::<_, k256::ProjectivePoint>(&mut rand_core::OsRng);
@@ -161,12 +143,9 @@ fn test_secp256k1() {
 /// Ciphersuite for P-256.
 ///
 /// hash_to_F is implemented via the IETF draft for hash to curve's hash_to_field (v16).
-#[cfg(feature = "p256")]
 #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
 pub struct P256;
-#[cfg(feature = "p256")]
 kp_curve!("p256", p256, P256, b"P-256");
-#[cfg(feature = "p256")]
 #[test]
 fn test_p256() {
   ff_group_tests::group::test_prime_group_bits::<_, p256::ProjectivePoint>(&mut rand_core::OsRng);

crypto/ciphersuite/src/lib.md

@@ -2,7 +2,7 @@
 
 Ciphersuites for elliptic curves premised on ff/group.
 
-This library, except for the not recommended Ed448 ciphersuite, was
+This library was
 [audited by Cypher Stack in March 2023](https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf),
 culminating in commit
 [669d2dbffc1dafb82a09d9419ea182667115df06](https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06).

crypto/ciphersuite/src/lib.rs

@@ -4,6 +4,9 @@
 
 use core::fmt::Debug;
 #[cfg(any(feature = "alloc", feature = "std"))]
+#[allow(unused_imports)]
+use std_shims::prelude::*;
+#[cfg(any(feature = "alloc", feature = "std"))]
 use std_shims::io::{self, Read};
 
 use rand_core::{RngCore, CryptoRng};
@@ -23,25 +26,6 @@ use group::{
 #[cfg(any(feature = "alloc", feature = "std"))]
 use group::GroupEncoding;
 
-#[cfg(feature = "dalek")]
-mod dalek;
-#[cfg(feature = "ristretto")]
-pub use dalek::Ristretto;
-#[cfg(feature = "ed25519")]
-pub use dalek::Ed25519;
-
-#[cfg(feature = "kp256")]
-mod kp256;
-#[cfg(feature = "secp256k1")]
-pub use kp256::Secp256k1;
-#[cfg(feature = "p256")]
-pub use kp256::P256;
-
-#[cfg(feature = "ed448")]
-mod ed448;
-#[cfg(feature = "ed448")]
-pub use ed448::*;
-
 /// Unified trait defining a ciphersuite around an elliptic curve.
 pub trait Ciphersuite:
   'static + Send + Sync + Clone + Copy + PartialEq + Eq + Debug + Zeroize
@@ -62,12 +46,6 @@ pub trait Ciphersuite:
   // While group does provide this in its API, privacy coins may want to use a custom basepoint
   fn generator() -> Self::G;
 
-  /// Reduce 512 bits into a uniform scalar.
-  ///
-  /// If 512 bits is insufficient to perform a reduction into a uniform scalar, the ciphersuite
-  /// will perform a hash to sample the necessary bits.
-  fn reduce_512(scalar: [u8; 64]) -> Self::F;
-
   /// Hash the provided domain-separation tag and message to a scalar. Ciphersuites MAY naively
   /// prefix the tag to the message, enabling transpotion between the two. Accordingly, this
   /// function should NOT be used in any scheme where one tag is a valid substring of another

crypto/dalek-ff-group/Cargo.toml

@@ -1,13 +1,13 @@
 [package]
 name = "dalek-ff-group"
-version = "0.4.1"
+version = "0.4.4"
 description = "ff/group bindings around curve25519-dalek"
 license = "MIT"
 repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dalek-ff-group"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["curve25519", "ed25519", "ristretto", "dalek", "group"]
 edition = "2021"
-rust-version = "1.71"
+rust-version = "1.65"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -25,18 +25,22 @@ subtle = { version = "^2.4", default-features = false }
 rand_core = { version = "0.6", default-features = false }
 
 digest = { version = "0.10", default-features = false }
+sha2 = { version = "0.10", default-features = false }
 
 ff = { version = "0.13", default-features = false, features = ["bits"] }
 group = { version = "0.13", default-features = false }
+ciphersuite = { path = "../ciphersuite", default-features = false }
 
 crypto-bigint = { version = "0.5", default-features = false, features = ["zeroize"] }
 
 curve25519-dalek = { version = ">= 4.0, < 4.2", default-features = false, features = ["alloc", "zeroize", "digest", "group", "precomputed-tables"] }
 
 [dev-dependencies]
+hex = "0.4"
 rand_core = { version = "0.6", default-features = false, features = ["std"] }
 ff-group-tests = { path = "../ff-group-tests" }
 
 [features]
-std = ["zeroize/std", "subtle/std", "rand_core/std", "digest/std"]
+alloc = ["zeroize/alloc", "ciphersuite/alloc"]
+std = ["alloc", "zeroize/std", "subtle/std", "rand_core/std", "digest/std", "sha2/std", "ciphersuite/std"]
 default = ["std"]

crypto/dalek-ff-group/src/ciphersuite.rs

@@ -3,9 +3,9 @@ use zeroize::Zeroize;
 use sha2::{Digest, Sha512};
 
 use group::Group;
-use dalek_ff_group::Scalar;
+use crate::Scalar;
 
-use crate::Ciphersuite;
+use ciphersuite::Ciphersuite;
 
 macro_rules! dalek_curve {
   (
@@ -15,7 +15,7 @@ macro_rules! dalek_curve {
     $Point:       ident,
     $ID:          literal
   ) => {
-    use dalek_ff_group::$Point;
+    use crate::$Point;
 
     impl Ciphersuite for $Ciphersuite {
       type F = Scalar;
@@ -28,12 +28,6 @@ macro_rules! dalek_curve {
         $Point::generator()
       }
 
-      fn reduce_512(mut scalar: [u8; 64]) -> Self::F {
-        let res = Scalar::from_bytes_mod_order_wide(&scalar);
-        scalar.zeroize();
-        res
-      }
-
       fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
         Scalar::from_hash(Sha512::new_with_prefix(&[dst, data].concat()))
       }
@@ -46,12 +40,9 @@ macro_rules! dalek_curve {
 /// hash_to_F is implemented with a naive concatenation of the dst and data, allowing transposition
 /// between the two. This means `dst: b"abc", data: b"def"`, will produce the same scalar as
 /// `dst: "abcdef", data: b""`. Please use carefully, not letting dsts be substrings of each other.
-#[cfg(any(test, feature = "ristretto"))]
 #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
 pub struct Ristretto;
-#[cfg(any(test, feature = "ristretto"))]
 dalek_curve!("ristretto", Ristretto, RistrettoPoint, b"ristretto");
-#[cfg(any(test, feature = "ristretto"))]
 #[test]
 fn test_ristretto() {
   ff_group_tests::group::test_prime_group_bits::<_, RistrettoPoint>(&mut rand_core::OsRng);
@@ -77,12 +68,9 @@ fn test_ristretto() {
 /// hash_to_F is implemented with a naive concatenation of the dst and data, allowing transposition
 /// between the two. This means `dst: b"abc", data: b"def"`, will produce the same scalar as
 /// `dst: "abcdef", data: b""`. Please use carefully, not letting dsts be substrings of each other.
-#[cfg(feature = "ed25519")]
 #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
 pub struct Ed25519;
-#[cfg(feature = "ed25519")]
 dalek_curve!("ed25519", Ed25519, EdwardsPoint, b"edwards25519");
-#[cfg(feature = "ed25519")]
 #[test]
 fn test_ed25519() {
   ff_group_tests::group::test_prime_group_bits::<_, EdwardsPoint>(&mut rand_core::OsRng);

crypto/dalek-ff-group/src/field.rs

@@ -17,7 +17,7 @@ use crypto_bigint::{
   impl_modulus,
 };
 
-use group::ff::{Field, PrimeField, FieldBits, PrimeFieldBits};
+use group::ff::{Field, PrimeField, FieldBits, PrimeFieldBits, FromUniformBytes};
 
 use crate::{u8_from_bool, constant_time, math_op, math};
 
@@ -36,6 +36,7 @@ type ResidueType = Residue<FieldModulus, { FieldModulus::LIMBS }>;
 
 /// A constant-time implementation of the Ed25519 field.
 #[derive(Clone, Copy, PartialEq, Eq, Default, Debug, Zeroize)]
+#[repr(transparent)]
 pub struct FieldElement(ResidueType);
 
 // Square root of -1.
@@ -216,10 +217,18 @@ impl PrimeFieldBits for FieldElement {
 }
 
 impl FieldElement {
-  /// Interpret the value as a little-endian integer, square it, and reduce it into a FieldElement.
-  pub fn from_square(value: [u8; 32]) -> FieldElement {
-    let value = U256::from_le_bytes(value);
-    FieldElement(reduce(U512::from(value.mul_wide(&value))))
+  /// Create a FieldElement from a `crypto_bigint::U256`.
+  ///
+  /// This will reduce the `U256` by the modulus, into a member of the field.
+  pub const fn from_u256(u256: &U256) -> Self {
+    FieldElement(Residue::new(u256))
+  }
+
+  /// Create a `FieldElement` from the reduction of a 512-bit number.
+  ///
+  /// The bytes are interpreted in little-endian format.
+  pub fn wide_reduce(value: [u8; 64]) -> Self {
+    FieldElement(reduce(U512::from_le_bytes(value)))
   }
 
   /// Perform an exponentiation.
@@ -297,6 +306,12 @@ impl FieldElement {
   }
 }
 
+impl FromUniformBytes<64> for FieldElement {
+  fn from_uniform_bytes(bytes: &[u8; 64]) -> Self {
+    Self::wide_reduce(*bytes)
+  }
+}
+
 impl Sum<FieldElement> for FieldElement {
   fn sum<I: Iterator<Item = FieldElement>>(iter: I) -> FieldElement {
     let mut res = FieldElement::ZERO;

crypto/dalek-ff-group/src/lib.rs

@@ -30,7 +30,7 @@ use dalek::{
 pub use constants::{ED25519_BASEPOINT_TABLE, RISTRETTO_BASEPOINT_TABLE};
 
 use group::{
-  ff::{Field, PrimeField, FieldBits, PrimeFieldBits},
+  ff::{Field, PrimeField, FieldBits, PrimeFieldBits, FromUniformBytes},
   Group, GroupEncoding,
   prime::PrimeGroup,
 };
@@ -38,13 +38,24 @@ use group::{
 mod field;
 pub use field::FieldElement;
 
+mod ciphersuite;
+pub use crate::ciphersuite::{Ed25519, Ristretto};
+
 // Use black_box when possible
 #[rustversion::since(1.66)]
-use core::hint::black_box;
-#[rustversion::before(1.66)]
-fn black_box<T>(val: T) -> T {
-  val
+mod black_box {
+  pub(crate) fn black_box<T>(val: T) -> T {
+    #[allow(clippy::incompatible_msrv)]
+    core::hint::black_box(val)
+  }
 }
+#[rustversion::before(1.66)]
+mod black_box {
+  pub(crate) fn black_box<T>(val: T) -> T {
+    val
+  }
+}
+use black_box::black_box;
 
 fn u8_from_bool(bit_ref: &mut bool) -> u8 {
   let bit_ref = black_box(bit_ref);
@@ -314,6 +325,12 @@ impl PrimeFieldBits for Scalar {
   }
 }
 
+impl FromUniformBytes<64> for Scalar {
+  fn from_uniform_bytes(bytes: &[u8; 64]) -> Self {
+    Self::from_bytes_mod_order_wide(bytes)
+  }
+}
+
 impl Sum<Scalar> for Scalar {
   fn sum<I: Iterator<Item = Scalar>>(iter: I) -> Scalar {
     Self(DScalar::sum(iter))
@@ -351,7 +368,12 @@ macro_rules! dalek_group {
     $BASEPOINT_POINT: ident,
     $BASEPOINT_TABLE: ident
   ) => {
-    /// Wrapper around the dalek Point type. For Ed25519, this is restricted to the prime subgroup.
+    /// Wrapper around the dalek Point type.
+    ///
+    /// All operations will be restricted to a prime-order subgroup (equivalent to the group itself
+    /// in the case of Ristretto). The exposure of the internal element does allow bypassing this
+    /// however, which may lead to undefined/computationally-unsafe behavior, and is entirely at
+    /// the user's risk.
     #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
     pub struct $Point(pub $DPoint);
     deref_borrow!($Point, $DPoint);

crypto/dkg/Cargo.toml

@@ -1,13 +1,13 @@
 [package]
 name = "dkg"
-version = "0.5.1"
+version = "0.6.1"
 description = "Distributed key generation over ff/group"
 license = "MIT"
 repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["dkg", "multisig", "threshold", "ff", "group"]
 edition = "2021"
-rust-version = "1.81"
+rust-version = "1.66"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -17,82 +17,25 @@ rustdoc-args = ["--cfg", "docsrs"]
 workspace = true
 
 [dependencies]
+zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive", "alloc"] }
+
 thiserror = { version = "2", default-features = false }
 
-rand_core = { version = "0.6", default-features = false }
-
-zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive"] }
-
 std-shims = { version = "0.1", path = "../../common/std-shims", default-features = false }
 
 borsh = { version = "1", default-features = false, features = ["derive", "de_strict_order"], optional = true }
 
-transcript = { package = "flexible-transcript", path = "../transcript", version = "^0.3.2", default-features = false, features = ["recommended"] }
-chacha20 = { version = "0.9", default-features = false, features = ["zeroize"] }
-
-ciphersuite = { path = "../ciphersuite", version = "^0.4.1", default-features = false }
-multiexp = { path = "../multiexp", version = "0.4", default-features = false }
-
-schnorr = { package = "schnorr-signatures", path = "../schnorr", version = "^0.5.1", default-features = false }
-dleq = { path = "../dleq", version = "^0.4.1", default-features = false }
-
-# eVRF DKG dependencies
-generic-array = { version = "1", default-features = false, features = ["alloc"], optional = true }
-blake2 = { version = "0.10", default-features = false, features = ["std"], optional = true }
-rand_chacha = { version = "0.3", default-features = false, features = ["std"], optional = true }
-generalized-bulletproofs = { path = "../evrf/generalized-bulletproofs", default-features = false, optional = true }
-ec-divisors = { path = "../evrf/divisors", default-features = false, optional = true }
-generalized-bulletproofs-circuit-abstraction = { path = "../evrf/circuit-abstraction", optional = true }
-generalized-bulletproofs-ec-gadgets = { path = "../evrf/ec-gadgets", optional = true }
-
-secq256k1 = { path = "../evrf/secq256k1", optional = true }
-embedwards25519 = { path = "../evrf/embedwards25519", optional = true }
-
-[dev-dependencies]
-rand_core = { version = "0.6", default-features = false, features = ["getrandom"] }
-rand = { version = "0.8", default-features = false, features = ["std"] }
-ciphersuite = { path = "../ciphersuite", default-features = false, features = ["ristretto"] }
-generalized-bulletproofs = { path = "../evrf/generalized-bulletproofs", features = ["tests"] }
-ec-divisors = { path = "../evrf/divisors", features = ["pasta"] }
-pasta_curves = { git = "https://github.com/kayabaNerve/pasta_curves", rev = "a46b5be95cacbff54d06aad8d3bbcba42e05d616" }
+ciphersuite = { path = "../ciphersuite", version = "^0.4.1", default-features = false, features = ["alloc"] }
 
 [features]
 std = [
   "thiserror/std",
 
-  "rand_core/std",
-
   "std-shims/std",
 
   "borsh?/std",
 
-  "transcript/std",
-  "chacha20/std",
-
   "ciphersuite/std",
-  "multiexp/std",
-  "multiexp/batch",
-
-  "schnorr/std",
-  "dleq/std",
-  "dleq/serialize"
 ]
 borsh = ["dep:borsh"]
-evrf = [
-  "std",
-
-  "dep:generic-array",
-
-  "dep:blake2",
-  "dep:rand_chacha",
-
-  "dep:generalized-bulletproofs",
-  "dep:ec-divisors",
-  "dep:generalized-bulletproofs-circuit-abstraction",
-  "dep:generalized-bulletproofs-ec-gadgets",
-]
-evrf-secp256k1 = ["evrf", "ciphersuite/secp256k1", "secq256k1"]
-evrf-ed25519 = ["evrf", "ciphersuite/ed25519", "embedwards25519"]
-evrf-ristretto = ["evrf", "ciphersuite/ristretto", "embedwards25519"]
-tests = ["rand_core/getrandom"]
 default = ["std"]

crypto/dkg/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2021-2023 Luke Parker
+Copyright (c) 2021-2025 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

crypto/dkg/README.md

@@ -1,16 +1,15 @@
 # Distributed Key Generation
 
-A collection of implementations of various distributed key generation protocols.
+A crate implementing a type for keys, presumably the result of a distributed
+key generation protocol, and utilities from there.
 
-All included protocols resolve into the provided `Threshold` types, intended to
-enable their modularity. Additional utilities around these types, such as
-promotion from one generator to another, are also provided.
+This crate used to host implementations of distributed key generation protocols
+as well (hence the name). Those have been smashed into their own crates, such
+as [`dkg-musig`](https://docs.rs/dkg-musig) and
+[`dkg-pedpop`](https://docs.rs/dkg-pedpop).
 
-Currently, the only included protocol is the two-round protocol from the
-[FROST paper](https://eprint.iacr.org/2020/852).
-
-This library was
-[audited by Cypher Stack in March 2023](https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf),
-culminating in commit
-[669d2dbffc1dafb82a09d9419ea182667115df06](https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06).
-Any subsequent changes have not undergone auditing.
+Before being smashed, this crate was [audited by Cypher Stack in March 2023](
+  https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf
+), culminating in commit [669d2dbffc1dafb82a09d9419ea182667115df06](
+  https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06
+). Any subsequent changes have not undergone auditing.

crypto/dkg/dealer/Cargo.toml

@@ -0,0 +1,36 @@
+[package]
+name = "dkg-dealer"
+version = "0.6.0"
+description = "Produce dkg::ThresholdKeys with a dealer key generation"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/dealer"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+keywords = ["dkg", "multisig", "threshold", "ff", "group"]
+edition = "2021"
+rust-version = "1.66"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+zeroize = { version = "^1.5", default-features = false }
+rand_core = { version = "0.6", default-features = false }
+
+std-shims = { version = "0.1", path = "../../../common/std-shims", default-features = false }
+
+ciphersuite = { path = "../../ciphersuite", version = "^0.4.1", default-features = false }
+dkg = { path = "../", version = "0.6", default-features = false }
+
+[features]
+std = [
+  "zeroize/std",
+  "rand_core/std",
+  "std-shims/std",
+  "ciphersuite/std",
+  "dkg/std",
+]
+default = ["std"]

crypto/dkg/dealer/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2024 Luke Parker
+Copyright (c) 2021-2025 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

crypto/dkg/dealer/README.md

@@ -0,0 +1,13 @@
+# Distributed Key Generation - Dealer
+
+This crate implements a dealer key generation protocol for the
+[`dkg`](https://docs.rs/dkg) crate's types. This provides a single point of
+failure when the key is being generated and is NOT recommended for use outside
+of tests.
+
+This crate was originally part of (in some form) the `dkg` crate, which was
+[audited by Cypher Stack in March 2023](
+  https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf
+), culminating in commit [669d2dbffc1dafb82a09d9419ea182667115df06](
+  https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06
+). Any subsequent changes have not undergone auditing.

crypto/dkg/dealer/src/lib.rs

@@ -0,0 +1,68 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+#![no_std]
+
+use core::ops::Deref;
+use std_shims::{vec::Vec, collections::HashMap};
+
+use zeroize::{Zeroize, Zeroizing};
+use rand_core::{RngCore, CryptoRng};
+
+use ciphersuite::{
+  group::ff::{Field, PrimeField},
+  Ciphersuite,
+};
+pub use dkg::*;
+
+/// Create a key via a dealer key generation protocol.
+pub fn key_gen<R: RngCore + CryptoRng, C: Ciphersuite>(
+  rng: &mut R,
+  threshold: u16,
+  participants: u16,
+) -> Result<HashMap<Participant, ThresholdKeys<C>>, DkgError> {
+  let mut coefficients = Vec::with_capacity(usize::from(participants));
+  // `.max(1)` so we always generate the 0th coefficient which we'll share
+  for _ in 0 .. threshold.max(1) {
+    coefficients.push(Zeroizing::new(C::F::random(&mut *rng)));
+  }
+
+  fn polynomial<F: PrimeField + Zeroize>(
+    coefficients: &[Zeroizing<F>],
+    l: Participant,
+  ) -> Zeroizing<F> {
+    let l = F::from(u64::from(u16::from(l)));
+    // This should never be reached since Participant is explicitly non-zero
+    assert!(l != F::ZERO, "zero participant passed to polynomial");
+    let mut share = Zeroizing::new(F::ZERO);
+    for (idx, coefficient) in coefficients.iter().rev().enumerate() {
+      *share += coefficient.deref();
+      if idx != (coefficients.len() - 1) {
+        *share *= l;
+      }
+    }
+    share
+  }
+
+  let group_key = C::generator() * coefficients[0].deref();
+  let mut secret_shares = HashMap::with_capacity(participants as usize);
+  let mut verification_shares = HashMap::with_capacity(participants as usize);
+  for i in 1 ..= participants {
+    let i = Participant::new(i).expect("non-zero u16 wasn't a valid Participant index");
+    let secret_share = polynomial(&coefficients, i);
+    secret_shares.insert(i, secret_share.clone());
+    verification_shares.insert(i, C::generator() * *secret_share);
+  }
+
+  let mut res = HashMap::with_capacity(participants as usize);
+  for (i, secret_share) in secret_shares {
+    let keys = ThresholdKeys::new(
+      ThresholdParams::new(threshold, participants, i)?,
+      Interpolation::Lagrange,
+      secret_share,
+      verification_shares.clone(),
+    )?;
+    debug_assert_eq!(keys.group_key(), group_key);
+    res.insert(i, keys);
+  }
+  Ok(res)
+}

crypto/dkg/evrf/Cargo.toml

@@ -0,0 +1,68 @@
+[package]
+name = "dkg-evrf"
+version = "0.1.0"
+description = "Distributed key generation over ff/group"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/evrf"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+keywords = ["dkg", "multisig", "threshold", "ff", "group"]
+edition = "2021"
+rust-version = "1.81"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+thiserror = { version = "2", default-features = false }
+
+rand_core = { version = "0.6", default-features = false }
+
+zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive"] }
+
+transcript = { package = "flexible-transcript", path = "../../transcript", version = "^0.3.2", default-features = false, features = ["recommended"] }
+
+ciphersuite = { path = "../../ciphersuite", version = "^0.4.1", default-features = false }
+multiexp = { path = "../../multiexp", version = "0.4", default-features = false }
+
+generic-array = { version = "1", default-features = false, features = ["alloc"] }
+blake2 = { version = "0.10", default-features = false, features = ["std"] }
+rand_chacha = { version = "0.3", default-features = false, features = ["std"] }
+generalized-bulletproofs = { git = "https://github.com/kayabaNerve/monero-oxide", rev = "b6dd1a9ff7ac6b96eb7cb488a4501fd1f6f2dd1e", default-features = false }
+ec-divisors = { git = "https://github.com/kayabaNerve/monero-oxide", rev = "b6dd1a9ff7ac6b96eb7cb488a4501fd1f6f2dd1e", default-features = false }
+generalized-bulletproofs-circuit-abstraction = { git = "https://github.com/kayabaNerve/monero-oxide", rev = "b6dd1a9ff7ac6b96eb7cb488a4501fd1f6f2dd1e" }
+generalized-bulletproofs-ec-gadgets = { git = "https://github.com/kayabaNerve/monero-oxide", rev = "b6dd1a9ff7ac6b96eb7cb488a4501fd1f6f2dd1e" }
+
+dkg = { path = ".." }
+
+secq256k1 = { path = "../../evrf/secq256k1", optional = true }
+embedwards25519 = { path = "../../evrf/embedwards25519", optional = true }
+
+[dev-dependencies]
+rand_core = { version = "0.6", default-features = false, features = ["getrandom"] }
+rand = { version = "0.8", default-features = false, features = ["std"] }
+ciphersuite = { path = "../../ciphersuite", default-features = false, features = ["std"]  }
+dalek-ff-group = { path = "../../dalek-ff-group", default-features = false, features = ["std"] }
+generalized-bulletproofs = { git = "https://github.com/kayabaNerve/monero-oxide", rev = "b6dd1a9ff7ac6b96eb7cb488a4501fd1f6f2dd1e", features = ["tests"] }
+ec-divisors = { git = "https://github.com/kayabaNerve/monero-oxide", rev = "b6dd1a9ff7ac6b96eb7cb488a4501fd1f6f2dd1e" }
+
+[features]
+std = [
+  "thiserror/std",
+
+  "rand_core/std",
+
+  "transcript/std",
+
+  "ciphersuite/std",
+  "multiexp/std",
+  "multiexp/batch",
+]
+secp256k1 = ["secq256k1"]
+ed25519 = ["embedwards25519"]
+ristretto = ["embedwards25519"]
+tests = ["rand_core/getrandom"]
+default = ["std"]

crypto/dkg/evrf/src/lib.rs

@@ -88,7 +88,7 @@ use multiexp::multiexp_vartime;
 use generalized_bulletproofs::{Generators, arithmetic_circuit_proof::*};
 use ec_divisors::DivisorCurve;
 
-use crate::{Participant, ThresholdParams, Interpolation, ThresholdCore, ThresholdKeys};
+use dkg::{Participant, ThresholdParams, Interpolation, ThresholdKeys};
 
 pub(crate) mod proof;
 use proof::*;

crypto/dkg/evrf/src/tests/proof.rs

@@ -35,9 +35,6 @@ impl Ciphersuite for Pallas {
     // This is solely test code so it's fine
     Self::F::from_uniform_bytes(&Self::H::digest([dst, msg].concat()).into())
   }
-  fn reduce_512(scalar: [u8; 64]) -> Self::F {
-    Self::F::from_uniform_bytes(&scalar)
-  }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
@@ -55,9 +52,6 @@ impl Ciphersuite for Vesta {
     // This is solely test code so it's fine
     Self::F::from_uniform_bytes(&Self::H::digest([dst, msg].concat()).into())
   }
-  fn reduce_512(scalar: [u8; 64]) -> Self::F {
-    Self::F::from_uniform_bytes(&scalar)
-  }
 }
 
 pub struct VestaParams;

crypto/dkg/musig/Cargo.toml

@@ -0,0 +1,49 @@
+[package]
+name = "dkg-musig"
+version = "0.6.0"
+description = "The MuSig key aggregation protocol"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/musig"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+keywords = ["dkg", "multisig", "threshold", "ff", "group"]
+edition = "2021"
+rust-version = "1.79"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+thiserror = { version = "2", default-features = false }
+
+rand_core = { version = "0.6", default-features = false }
+
+zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive"] }
+
+std-shims = { version = "0.1", path = "../../../common/std-shims", default-features = false }
+
+multiexp = { path = "../../multiexp", version = "0.4", default-features = false }
+ciphersuite = { path = "../../ciphersuite", version = "^0.4.1", default-features = false }
+dkg = { path = "../", version = "0.6", default-features = false }
+
+[dev-dependencies]
+rand_core = { version = "0.6", default-features = false, features = ["getrandom"] }
+dalek-ff-group = { path = "../../dalek-ff-group" }
+dkg-recovery = { path = "../recovery", default-features = false, features = ["std"] }
+
+[features]
+std = [
+  "thiserror/std",
+
+  "rand_core/std",
+
+  "std-shims/std",
+
+  "multiexp/std",
+  "ciphersuite/std",
+  "dkg/std",
+]
+default = ["std"]

crypto/dkg/musig/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2021-2024 Luke Parker
+Copyright (c) 2021-2025 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

crypto/dkg/musig/README.md

@@ -0,0 +1,12 @@
+# Distributed Key Generation - MuSig
+
+This implements the MuSig key aggregation protocol for the
+[`dkg`](https://docs.rs/dkg) crate's types.
+
+This crate was originally part of (in some form) the `dkg` crate, which was
+[audited by Cypher Stack in March 2023](
+  https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf
+), culminating in commit
+[669d2dbffc1dafb82a09d9419ea182667115df06](
+  https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06
+). Any subsequent changes have not undergone auditing.

crypto/dkg/musig/src/lib.rs

@@ -0,0 +1,162 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use core::ops::Deref;
+use std_shims::{
+  vec,
+  vec::Vec,
+  collections::{HashSet, HashMap},
+};
+
+use zeroize::Zeroizing;
+
+use ciphersuite::{group::GroupEncoding, Ciphersuite};
+
+pub use dkg::*;
+
+#[cfg(test)]
+mod tests;
+
+/// Errors encountered when working with threshold keys.
+#[derive(Clone, PartialEq, Eq, Debug, thiserror::Error)]
+pub enum MusigError<C: Ciphersuite> {
+  /// No keys were provided.
+  #[error("no keys provided")]
+  NoKeysProvided,
+  /// Too many keys were provided.
+  #[error("too many keys (allowed {max}, provided {provided})")]
+  TooManyKeysProvided {
+    /// The maximum amount of keys allowed.
+    max: u16,
+    /// The amount of keys provided.
+    provided: usize,
+  },
+  /// A participant was duplicated.
+  #[error("a participant was duplicated")]
+  DuplicatedParticipant(C::G),
+  /// Participating, yet our public key wasn't found in the list of keys.
+  #[error("private key's public key wasn't present in the list of public keys")]
+  NotPresent,
+  /// An error propagated from the underlying `dkg` crate.
+  #[error("error from dkg ({0})")]
+  DkgError(DkgError),
+}
+
+fn check_keys<C: Ciphersuite>(keys: &[C::G]) -> Result<u16, MusigError<C>> {
+  if keys.is_empty() {
+    Err(MusigError::NoKeysProvided)?;
+  }
+
+  let keys_len = u16::try_from(keys.len())
+    .map_err(|_| MusigError::TooManyKeysProvided { max: u16::MAX, provided: keys.len() })?;
+
+  let mut set = HashSet::with_capacity(keys.len());
+  for key in keys {
+    let bytes = key.to_bytes().as_ref().to_vec();
+    if !set.insert(bytes) {
+      Err(MusigError::DuplicatedParticipant(*key))?;
+    }
+  }
+
+  Ok(keys_len)
+}
+
+fn binding_factor_transcript<C: Ciphersuite>(
+  context: [u8; 32],
+  keys_len: u16,
+  keys: &[C::G],
+) -> Vec<u8> {
+  debug_assert_eq!(usize::from(keys_len), keys.len());
+
+  let mut transcript = vec![];
+  transcript.extend(&context);
+  transcript.extend(keys_len.to_le_bytes());
+  for key in keys {
+    transcript.extend(key.to_bytes().as_ref());
+  }
+  transcript
+}
+
+fn binding_factor<C: Ciphersuite>(mut transcript: Vec<u8>, i: u16) -> C::F {
+  transcript.extend(i.to_le_bytes());
+  C::hash_to_F(b"dkg-musig", &transcript)
+}
+
+#[allow(clippy::type_complexity)]
+fn musig_key_multiexp<C: Ciphersuite>(
+  context: [u8; 32],
+  keys: &[C::G],
+) -> Result<Vec<(C::F, C::G)>, MusigError<C>> {
+  let keys_len = check_keys::<C>(keys)?;
+  let transcript = binding_factor_transcript::<C>(context, keys_len, keys);
+  let mut multiexp = Vec::with_capacity(keys.len());
+  for i in 1 ..= keys_len {
+    multiexp.push((binding_factor::<C>(transcript.clone(), i), keys[usize::from(i - 1)]));
+  }
+  Ok(multiexp)
+}
+
+/// The group key resulting from using this library's MuSig key aggregation.
+///
+/// This function executes in variable time and MUST NOT be used with secret data.
+pub fn musig_key_vartime<C: Ciphersuite>(
+  context: [u8; 32],
+  keys: &[C::G],
+) -> Result<C::G, MusigError<C>> {
+  Ok(multiexp::multiexp_vartime(&musig_key_multiexp(context, keys)?))
+}
+
+/// The group key resulting from using this library's MuSig key aggregation.
+pub fn musig_key<C: Ciphersuite>(context: [u8; 32], keys: &[C::G]) -> Result<C::G, MusigError<C>> {
+  Ok(multiexp::multiexp(&musig_key_multiexp(context, keys)?))
+}
+
+/// A n-of-n non-interactive DKG which does not guarantee the usability of the resulting key.
+pub fn musig<C: Ciphersuite>(
+  context: [u8; 32],
+  private_key: Zeroizing<C::F>,
+  keys: &[C::G],
+) -> Result<ThresholdKeys<C>, MusigError<C>> {
+  let our_pub_key = C::generator() * private_key.deref();
+  let Some(our_i) = keys.iter().position(|key| *key == our_pub_key) else {
+    Err(MusigError::DkgError(DkgError::NotParticipating))?
+  };
+
+  let keys_len: u16 = check_keys::<C>(keys)?;
+
+  let params = ThresholdParams::new(
+    keys_len,
+    keys_len,
+    // The `+ 1` won't fail as `keys.len() <= u16::MAX`, so any index is `< u16::MAX`
+    Participant::new(
+      u16::try_from(our_i).expect("keys.len() <= u16::MAX yet index of keys > u16::MAX?") + 1,
+    )
+    .expect("i + 1 != 0"),
+  )
+  .map_err(MusigError::DkgError)?;
+
+  let transcript = binding_factor_transcript::<C>(context, keys_len, keys);
+  let mut binding_factors = Vec::with_capacity(keys.len());
+  let mut multiexp = Vec::with_capacity(keys.len());
+  let mut verification_shares = HashMap::with_capacity(keys.len());
+  for (i, key) in (1 ..= keys_len).zip(keys.iter().copied()) {
+    let binding_factor = binding_factor::<C>(transcript.clone(), i);
+    binding_factors.push(binding_factor);
+    multiexp.push((binding_factor, key));
+
+    let i = Participant::new(i).expect("non-zero u16 wasn't a valid Participant index?");
+    verification_shares.insert(i, key);
+  }
+  let group_key = multiexp::multiexp(&multiexp);
+  debug_assert_eq!(our_pub_key, verification_shares[&params.i()]);
+  debug_assert_eq!(musig_key_vartime::<C>(context, keys).unwrap(), group_key);
+
+  ThresholdKeys::new(
+    params,
+    Interpolation::Constant(binding_factors),
+    private_key,
+    verification_shares,
+  )
+  .map_err(MusigError::DkgError)
+}

crypto/dkg/musig/src/tests.rs

@@ -0,0 +1,71 @@
+use std::collections::HashMap;
+
+use zeroize::Zeroizing;
+use rand_core::OsRng;
+
+use dalek_ff_group::Ristretto;
+use ciphersuite::{group::ff::Field, Ciphersuite};
+
+use dkg_recovery::recover_key;
+use crate::*;
+
+/// Tests MuSig key generation.
+#[test]
+pub fn test_musig() {
+  const PARTICIPANTS: u16 = 5;
+
+  let mut keys = vec![];
+  let mut pub_keys = vec![];
+  for _ in 0 .. PARTICIPANTS {
+    let key = Zeroizing::new(<Ristretto as Ciphersuite>::F::random(&mut OsRng));
+    pub_keys.push(<Ristretto as Ciphersuite>::generator() * *key);
+    keys.push(key);
+  }
+
+  const CONTEXT: [u8; 32] = *b"MuSig Test                      ";
+
+  // Empty signing set
+  musig::<Ristretto>(CONTEXT, Zeroizing::new(<Ristretto as Ciphersuite>::F::ZERO), &[])
+    .unwrap_err();
+  // Signing set we're not part of
+  musig::<Ristretto>(
+    CONTEXT,
+    Zeroizing::new(<Ristretto as Ciphersuite>::F::ZERO),
+    &[<Ristretto as Ciphersuite>::generator()],
+  )
+  .unwrap_err();
+
+  // Test with n keys
+  {
+    let mut created_keys = HashMap::new();
+    let mut verification_shares = HashMap::new();
+    let group_key = musig_key::<Ristretto>(CONTEXT, &pub_keys).unwrap();
+    for (i, key) in keys.iter().enumerate() {
+      let these_keys = musig::<Ristretto>(CONTEXT, key.clone(), &pub_keys).unwrap();
+      assert_eq!(these_keys.params().t(), PARTICIPANTS);
+      assert_eq!(these_keys.params().n(), PARTICIPANTS);
+      assert_eq!(usize::from(u16::from(these_keys.params().i())), i + 1);
+
+      verification_shares.insert(
+        these_keys.params().i(),
+        <Ristretto as Ciphersuite>::generator() * **these_keys.original_secret_share(),
+      );
+
+      assert_eq!(these_keys.group_key(), group_key);
+
+      created_keys.insert(these_keys.params().i(), these_keys);
+    }
+
+    for keys in created_keys.values() {
+      for (l, verification_share) in &verification_shares {
+        assert_eq!(keys.original_verification_share(*l), *verification_share);
+      }
+    }
+
+    assert_eq!(
+      <Ristretto as Ciphersuite>::generator() *
+        *recover_key(&created_keys.values().cloned().collect::<Vec<_>>()).unwrap(),
+      group_key
+    );
+  }
+}

crypto/dkg/pedpop/Cargo.toml

@@ -0,0 +1,37 @@
+[package]
+name = "dkg-pedpop"
+version = "0.6.0"
+description = "The PedPoP distributed key generation protocol"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/pedpop"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+keywords = ["dkg", "multisig", "threshold", "ff", "group"]
+edition = "2021"
+rust-version = "1.80"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+thiserror = { version = "2", default-features = false, features = ["std"] }
+
+zeroize = { version = "^1.5", default-features = false, features = ["std", "zeroize_derive"] }
+rand_core = { version = "0.6", default-features = false, features = ["std"] }
+
+transcript = { package = "flexible-transcript", path = "../../transcript", version = "^0.3.3", default-features = false, features = ["std", "recommended"] }
+chacha20 = { version = "0.9", default-features = false, features = ["std", "zeroize"] }
+
+multiexp = { path = "../../multiexp", version = "0.4", default-features = false, features = ["std"] }
+ciphersuite = { path = "../../ciphersuite", version = "^0.4.1", default-features = false, features = ["std"] }
+schnorr = { package = "schnorr-signatures", path = "../../schnorr", version = "^0.5.1", default-features = false, features = ["std"] }
+dleq = { path = "../../dleq", version = "^0.4.1", default-features = false, features = ["std", "serialize"] }
+
+dkg = { path = "../", version = "0.6", default-features = false, features = ["std"] }
+
+[dev-dependencies]
+rand_core = { version = "0.6", default-features = false, features = ["getrandom"] }
+dalek-ff-group = { path = "../../dalek-ff-group", default-features = false }

crypto/dkg/pedpop/LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2024 Luke Parker
+Copyright (c) 2021-2025 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

crypto/dkg/pedpop/README.md

@@ -0,0 +1,12 @@
+# Distributed Key Generation - PedPoP
+
+This implements the PedPoP distributed key generation protocol for the
+[`dkg`](https://docs.rs/dkg) crate's types.
+
+This crate was originally part of the `dkg` crate, which was
+[audited by Cypher Stack in March 2023](
+  https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf
+), culminating in commit
+[669d2dbffc1dafb82a09d9419ea182667115df06](
+  https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06
+). Any subsequent changes have not undergone auditing.

crypto/dkg/pedpop/src/encryption.rs

@@ -21,7 +21,7 @@ use multiexp::BatchVerifier;
 use schnorr::SchnorrSignature;
 use dleq::DLEqProof;
 
-use crate::{Participant, ThresholdParams};
+use dkg::{Participant, ThresholdParams};
 
 mod sealed {
   use super::*;
@@ -69,7 +69,7 @@ impl<C: Ciphersuite, M: Message> EncryptionKeyMessage<C, M> {
     buf
   }
 
-  #[cfg(any(test, feature = "tests"))]
+  #[cfg(test)]
   pub(crate) fn enc_key(&self) -> C::G {
     self.enc_key
   }

crypto/dkg/pedpop/src/lib.rs

@@ -1,15 +1,20 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+// This crate requires `dleq` which doesn't support no-std via std-shims
+// #![cfg_attr(not(feature = "std"), no_std)]
+
 use core::{marker::PhantomData, ops::Deref, fmt};
 use std::{
   io::{self, Read, Write},
   collections::HashMap,
 };
 
-use rand_core::{RngCore, CryptoRng};
-
 use zeroize::{Zeroize, ZeroizeOnDrop, Zeroizing};
+use rand_core::{RngCore, CryptoRng};
 
 use transcript::{Transcript, RecommendedTranscript};
 
+use multiexp::{multiexp_vartime, BatchVerifier};
 use ciphersuite::{
   group::{
     ff::{Field, PrimeField},
@@ -17,29 +22,75 @@ use ciphersuite::{
   },
   Ciphersuite,
 };
-use multiexp::{multiexp_vartime, BatchVerifier};
 
 use schnorr::SchnorrSignature;
 
-use crate::{
-  Participant, DkgError, ThresholdParams, Interpolation, ThresholdCore, validate_map,
-  encryption::{
-    ReadWrite, EncryptionKeyMessage, EncryptedMessage, Encryption, Decryption, EncryptionKeyProof,
-    DecryptionError,
-  },
-};
+pub use dkg::*;
 
-type FrostError<C> = DkgError<EncryptionKeyProof<C>>;
+mod encryption;
+pub use encryption::*;
+
+#[cfg(test)]
+mod tests;
+
+/// Errors possible during key generation.
+#[derive(Clone, PartialEq, Eq, Debug, thiserror::Error)]
+pub enum PedPoPError<C: Ciphersuite> {
+  /// An incorrect amount of participants was provided.
+  #[error("incorrect amount of participants (expected {expected}, found {found})")]
+  IncorrectAmountOfParticipants { expected: usize, found: usize },
+  /// An invalid proof of knowledge was provided.
+  #[error("invalid proof of knowledge (participant {0})")]
+  InvalidCommitments(Participant),
+  /// An invalid DKG share was provided.
+  #[error("invalid share (participant {participant}, blame {blame})")]
+  InvalidShare { participant: Participant, blame: Option<EncryptionKeyProof<C>> },
+  /// A participant was missing.
+  #[error("missing participant {0}")]
+  MissingParticipant(Participant),
+  /// An error propagated from the underlying `dkg` crate.
+  #[error("error from dkg ({0})")]
+  DkgError(DkgError),
+}
+
+// Validate a map of values to have the expected included participants
+fn validate_map<T, C: Ciphersuite>(
+  map: &HashMap<Participant, T>,
+  included: &[Participant],
+  ours: Participant,
+) -> Result<(), PedPoPError<C>> {
+  if (map.len() + 1) != included.len() {
+    Err(PedPoPError::IncorrectAmountOfParticipants {
+      expected: included.len(),
+      found: map.len() + 1,
+    })?;
+  }
+
+  for included in included {
+    if *included == ours {
+      if map.contains_key(included) {
+        Err(PedPoPError::DkgError(DkgError::DuplicatedParticipant(*included)))?;
+      }
+      continue;
+    }
+
+    if !map.contains_key(included) {
+      Err(PedPoPError::MissingParticipant(*included))?;
+    }
+  }
+
+  Ok(())
+}
 
 #[allow(non_snake_case)]
 fn challenge<C: Ciphersuite>(context: [u8; 32], l: Participant, R: &[u8], Am: &[u8]) -> C::F {
-  let mut transcript = RecommendedTranscript::new(b"DKG FROST v0.2");
+  let mut transcript = RecommendedTranscript::new(b"DKG PedPoP v0.2");
   transcript.domain_separate(b"schnorr_proof_of_knowledge");
   transcript.append_message(b"context", context);
   transcript.append_message(b"participant", l.to_bytes());
   transcript.append_message(b"nonce", R);
   transcript.append_message(b"commitments", Am);
-  C::hash_to_F(b"DKG-FROST-proof_of_knowledge-0", &transcript.challenge(b"schnorr"))
+  C::hash_to_F(b"DKG-PedPoP-proof_of_knowledge-0", &transcript.challenge(b"schnorr"))
 }
 
 /// The commitments message, intended to be broadcast to all other parties.
@@ -98,7 +149,7 @@ impl<C: Ciphersuite> KeyGenMachine<C> {
     KeyGenMachine { params, context, _curve: PhantomData }
   }
 
-  /// Start generating a key according to the FROST DKG spec.
+  /// Start generating a key according to the PedPoP DKG specification present in the FROST paper.
   ///
   /// Returns a commitments message to be sent to all parties over an authenticated channel. If any
   /// party submits multiple sets of commitments, they MUST be treated as malicious.
@@ -106,7 +157,7 @@ impl<C: Ciphersuite> KeyGenMachine<C> {
     self,
     rng: &mut R,
   ) -> (SecretShareMachine<C>, EncryptionKeyMessage<C, Commitments<C>>) {
-    let t = usize::from(self.params.t);
+    let t = usize::from(self.params.t());
     let mut coefficients = Vec::with_capacity(t);
     let mut commitments = Vec::with_capacity(t);
     let mut cached_msg = vec![];
@@ -133,7 +184,7 @@ impl<C: Ciphersuite> KeyGenMachine<C> {
     );
 
     // Additionally create an encryption mechanism to protect the secret shares
-    let encryption = Encryption::new(self.context, self.params.i, rng);
+    let encryption = Encryption::new(self.context, self.params.i(), rng);
 
     // Step 4: Broadcast
     let msg =
@@ -250,21 +301,21 @@ impl<C: Ciphersuite> SecretShareMachine<C> {
     &mut self,
     rng: &mut R,
     mut commitment_msgs: HashMap<Participant, EncryptionKeyMessage<C, Commitments<C>>>,
-  ) -> Result<HashMap<Participant, Vec<C::G>>, FrostError<C>> {
+  ) -> Result<HashMap<Participant, Vec<C::G>>, PedPoPError<C>> {
     validate_map(
       &commitment_msgs,
-      &(1 ..= self.params.n()).map(Participant).collect::<Vec<_>>(),
+      &self.params.all_participant_indexes().collect::<Vec<_>>(),
       self.params.i(),
     )?;
 
     let mut batch = BatchVerifier::<Participant, C::G>::new(commitment_msgs.len());
     let mut commitments = HashMap::new();
-    for l in (1 ..= self.params.n()).map(Participant) {
+    for l in self.params.all_participant_indexes() {
       let Some(msg) = commitment_msgs.remove(&l) else { continue };
       let mut msg = self.encryption.register(l, msg);
 
       if msg.commitments.len() != self.params.t().into() {
-        Err(FrostError::InvalidCommitments(l))?;
+        Err(PedPoPError::InvalidCommitments(l))?;
       }
 
       // Step 5: Validate each proof of knowledge
@@ -280,9 +331,9 @@ impl<C: Ciphersuite> SecretShareMachine<C> {
       commitments.insert(l, msg.commitments.drain(..).collect::<Vec<_>>());
     }
 
-    batch.verify_vartime_with_vartime_blame().map_err(FrostError::InvalidCommitments)?;
+    batch.verify_vartime_with_vartime_blame().map_err(PedPoPError::InvalidCommitments)?;
 
-    commitments.insert(self.params.i, self.our_commitments.drain(..).collect());
+    commitments.insert(self.params.i(), self.our_commitments.drain(..).collect());
     Ok(commitments)
   }
 
@@ -299,13 +350,13 @@ impl<C: Ciphersuite> SecretShareMachine<C> {
     commitments: HashMap<Participant, EncryptionKeyMessage<C, Commitments<C>>>,
   ) -> Result<
     (KeyMachine<C>, HashMap<Participant, EncryptedMessage<C, SecretShare<C::F>>>),
-    FrostError<C>,
+    PedPoPError<C>,
   > {
     let commitments = self.verify_r1(&mut *rng, commitments)?;
 
     // Step 1: Generate secret shares for all other parties
     let mut res = HashMap::new();
-    for l in (1 ..= self.params.n()).map(Participant) {
+    for l in self.params.all_participant_indexes() {
       // Don't insert our own shares to the byte buffer which is meant to be sent around
       // An app developer could accidentally send it. Best to keep this black boxed
       if l == self.params.i() {
@@ -413,10 +464,10 @@ impl<C: Ciphersuite> KeyMachine<C> {
     mut self,
     rng: &mut R,
     mut shares: HashMap<Participant, EncryptedMessage<C, SecretShare<C::F>>>,
-  ) -> Result<BlameMachine<C>, FrostError<C>> {
+  ) -> Result<BlameMachine<C>, PedPoPError<C>> {
     validate_map(
       &shares,
-      &(1 ..= self.params.n()).map(Participant).collect::<Vec<_>>(),
+      &self.params.all_participant_indexes().collect::<Vec<_>>(),
       self.params.i(),
     )?;
 
@@ -427,7 +478,7 @@ impl<C: Ciphersuite> KeyMachine<C> {
         self.encryption.decrypt(rng, &mut batch, BatchId::Decryption(l), l, share_bytes);
       let share =
         Zeroizing::new(Option::<C::F>::from(C::F::from_repr(share_bytes.0)).ok_or_else(|| {
-          FrostError::InvalidShare { participant: l, blame: Some(blame.clone()) }
+          PedPoPError::InvalidShare { participant: l, blame: Some(blame.clone()) }
         })?);
       share_bytes.zeroize();
       *self.secret += share.deref();
@@ -444,7 +495,7 @@ impl<C: Ciphersuite> KeyMachine<C> {
         BatchId::Decryption(l) => (l, None),
         BatchId::Share(l) => (l, Some(blames.remove(&l).unwrap())),
       };
-      FrostError::InvalidShare { participant: l, blame }
+      PedPoPError::InvalidShare { participant: l, blame }
     })?;
 
     // Stripe commitments per t and sum them in advance. Calculating verification shares relies on
@@ -458,7 +509,7 @@ impl<C: Ciphersuite> KeyMachine<C> {
 
     // Calculate each user's verification share
     let mut verification_shares = HashMap::new();
-    for i in (1 ..= self.params.n()).map(Participant) {
+    for i in self.params.all_participant_indexes() {
       verification_shares.insert(
         i,
         if i == self.params.i() {
@@ -473,13 +524,10 @@ impl<C: Ciphersuite> KeyMachine<C> {
     Ok(BlameMachine {
       commitments,
       encryption: encryption.into_decryption(),
-      result: Some(ThresholdCore {
-        params,
-        interpolation: Interpolation::Lagrange,
-        secret_share: secret,
-        group_key: stripes[0],
-        verification_shares,
-      }),
+      result: Some(
+        ThresholdKeys::new(params, Interpolation::Lagrange, secret, verification_shares)
+          .map_err(PedPoPError::DkgError)?,
+      ),
     })
   }
 }
@@ -488,7 +536,7 @@ impl<C: Ciphersuite> KeyMachine<C> {
 pub struct BlameMachine<C: Ciphersuite> {
   commitments: HashMap<Participant, Vec<C::G>>,
   encryption: Decryption<C>,
-  result: Option<ThresholdCore<C>>,
+  result: Option<ThresholdKeys<C>>,
 }
 
 impl<C: Ciphersuite> fmt::Debug for BlameMachine<C> {
@@ -520,7 +568,7 @@ impl<C: Ciphersuite> BlameMachine<C> {
   /// territory of consensus protocols. This library does not handle that nor does it provide any
   /// tooling to do so. This function is solely intended to force users to acknowledge they're
   /// completing the protocol, not processing any blame.
-  pub fn complete(self) -> ThresholdCore<C> {
+  pub fn complete(self) -> ThresholdKeys<C> {
     self.result.unwrap()
   }
 
@@ -602,12 +650,12 @@ impl<C: Ciphersuite> AdditionalBlameMachine<C> {
     context: [u8; 32],
     n: u16,
     mut commitment_msgs: HashMap<Participant, EncryptionKeyMessage<C, Commitments<C>>>,
-  ) -> Result<Self, FrostError<C>> {
+  ) -> Result<Self, PedPoPError<C>> {
     let mut commitments = HashMap::new();
     let mut encryption = Decryption::new(context);
     for i in 1 ..= n {
       let i = Participant::new(i).unwrap();
-      let Some(msg) = commitment_msgs.remove(&i) else { Err(DkgError::MissingParticipant(i))? };
+      let Some(msg) = commitment_msgs.remove(&i) else { Err(PedPoPError::MissingParticipant(i))? };
       commitments.insert(i, encryption.register(i, msg).commitments);
     }
     Ok(AdditionalBlameMachine(BlameMachine { commitments, encryption, result: None }))

crypto/dkg/pedpop/src/tests.rs

@@ -0,0 +1,346 @@
+use std::collections::HashMap;
+
+use rand_core::{RngCore, CryptoRng, OsRng};
+
+use dalek_ff_group::Ristretto;
+use ciphersuite::Ciphersuite;
+
+use crate::*;
+
+const THRESHOLD: u16 = 3;
+const PARTICIPANTS: u16 = 5;
+
+/// Clone a map without a specific value.
+fn clone_without<K: Clone + core::cmp::Eq + core::hash::Hash, V: Clone>(
+  map: &HashMap<K, V>,
+  without: &K,
+) -> HashMap<K, V> {
+  let mut res = map.clone();
+  res.remove(without).unwrap();
+  res
+}
+
+type PedPoPEncryptedMessage<C> = EncryptedMessage<C, SecretShare<<C as Ciphersuite>::F>>;
+type PedPoPSecretShares<C> = HashMap<Participant, PedPoPEncryptedMessage<C>>;
+
+const CONTEXT: [u8; 32] = *b"DKG Test Key Generation         ";
+
+// Commit, then return commitment messages, enc keys, and shares
+#[allow(clippy::type_complexity)]
+fn commit_enc_keys_and_shares<R: RngCore + CryptoRng, C: Ciphersuite>(
+  rng: &mut R,
+) -> (
+  HashMap<Participant, KeyMachine<C>>,
+  HashMap<Participant, EncryptionKeyMessage<C, Commitments<C>>>,
+  HashMap<Participant, C::G>,
+  HashMap<Participant, PedPoPSecretShares<C>>,
+) {
+  let mut machines = HashMap::new();
+  let mut commitments = HashMap::new();
+  let mut enc_keys = HashMap::new();
+  for i in (1 ..= PARTICIPANTS).map(|i| Participant::new(i).unwrap()) {
+    let params = ThresholdParams::new(THRESHOLD, PARTICIPANTS, i).unwrap();
+    let machine = KeyGenMachine::<C>::new(params, CONTEXT);
+    let (machine, these_commitments) = machine.generate_coefficients(rng);
+    machines.insert(i, machine);
+
+    commitments.insert(
+      i,
+      EncryptionKeyMessage::read::<&[u8]>(&mut these_commitments.serialize().as_ref(), params)
+        .unwrap(),
+    );
+    enc_keys.insert(i, commitments[&i].enc_key());
+  }
+
+  let mut secret_shares = HashMap::new();
+  let machines = machines
+    .drain()
+    .map(|(l, machine)| {
+      let (machine, mut shares) =
+        machine.generate_secret_shares(rng, clone_without(&commitments, &l)).unwrap();
+      let shares = shares
+        .drain()
+        .map(|(l, share)| {
+          (
+            l,
+            EncryptedMessage::read::<&[u8]>(
+              &mut share.serialize().as_ref(),
+              // Only t/n actually matters, so hardcode i to 1 here
+              ThresholdParams::new(THRESHOLD, PARTICIPANTS, Participant::new(1).unwrap()).unwrap(),
+            )
+            .unwrap(),
+          )
+        })
+        .collect::<HashMap<_, _>>();
+      secret_shares.insert(l, shares);
+      (l, machine)
+    })
+    .collect::<HashMap<_, _>>();
+
+  (machines, commitments, enc_keys, secret_shares)
+}
+
+fn generate_secret_shares<C: Ciphersuite>(
+  shares: &HashMap<Participant, PedPoPSecretShares<C>>,
+  recipient: Participant,
+) -> PedPoPSecretShares<C> {
+  let mut our_secret_shares = HashMap::new();
+  for (i, shares) in shares {
+    if recipient == *i {
+      continue;
+    }
+    our_secret_shares.insert(*i, shares[&recipient].clone());
+  }
+  our_secret_shares
+}
+
+/// Fully perform the PedPoP key generation algorithm.
+fn pedpop_gen<R: RngCore + CryptoRng, C: Ciphersuite>(
+  rng: &mut R,
+) -> HashMap<Participant, ThresholdKeys<C>> {
+  let (mut machines, _, _, secret_shares) = commit_enc_keys_and_shares::<_, C>(rng);
+
+  let mut verification_shares = None;
+  let mut group_key = None;
+  machines
+    .drain()
+    .map(|(i, machine)| {
+      let our_secret_shares = generate_secret_shares(&secret_shares, i);
+      let these_keys = machine.calculate_share(rng, our_secret_shares).unwrap().complete();
+
+      // Verify the verification_shares are agreed upon
+      if verification_shares.is_none() {
+        verification_shares = Some(
+          these_keys
+            .params()
+            .all_participant_indexes()
+            .map(|i| (i, these_keys.original_verification_share(i)))
+            .collect::<HashMap<_, _>>(),
+        );
+      }
+      assert_eq!(
+        verification_shares.as_ref().unwrap(),
+        &these_keys
+          .params()
+          .all_participant_indexes()
+          .map(|i| (i, these_keys.original_verification_share(i)))
+          .collect::<HashMap<_, _>>()
+      );
+
+      // Verify the group keys are agreed upon
+      if group_key.is_none() {
+        group_key = Some(these_keys.group_key());
+      }
+      assert_eq!(group_key.unwrap(), these_keys.group_key());
+
+      (i, these_keys)
+    })
+    .collect::<HashMap<_, _>>()
+}
+
+const ONE: Participant = Participant::new(1).unwrap();
+const TWO: Participant = Participant::new(2).unwrap();
+
+#[test]
+fn test_pedpop() {
+  let _ = core::hint::black_box(pedpop_gen::<_, Ristretto>(&mut OsRng));
+}
+
+fn test_blame(
+  commitment_msgs: &HashMap<Participant, EncryptionKeyMessage<Ristretto, Commitments<Ristretto>>>,
+  machines: Vec<BlameMachine<Ristretto>>,
+  msg: &PedPoPEncryptedMessage<Ristretto>,
+  blame: &Option<EncryptionKeyProof<Ristretto>>,
+) {
+  for machine in machines {
+    let (additional, blamed) = machine.blame(ONE, TWO, msg.clone(), blame.clone());
+    assert_eq!(blamed, ONE);
+    // Verify additional blame also works
+    assert_eq!(additional.blame(ONE, TWO, msg.clone(), blame.clone()), ONE);
+
+    // Verify machines constructed with AdditionalBlameMachine::new work
+    assert_eq!(
+      AdditionalBlameMachine::new(CONTEXT, PARTICIPANTS, commitment_msgs.clone()).unwrap().blame(
+        ONE,
+        TWO,
+        msg.clone(),
+        blame.clone()
+      ),
+      ONE,
+    );
+  }
+}
+
+// TODO: Write a macro which expands to the following
+#[test]
+fn invalid_encryption_pop_blame() {
+  let (mut machines, commitment_msgs, _, mut secret_shares) =
+    commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
+
+  // Mutate the PoP of the encrypted message from 1 to 2
+  secret_shares.get_mut(&ONE).unwrap().get_mut(&TWO).unwrap().invalidate_pop();
+
+  let mut blame = None;
+  let machines = machines
+    .drain()
+    .filter_map(|(i, machine)| {
+      let our_secret_shares = generate_secret_shares(&secret_shares, i);
+      let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
+      if i == TWO {
+        assert_eq!(
+          machine.err(),
+          Some(PedPoPError::InvalidShare { participant: ONE, blame: None })
+        );
+        // Explicitly declare we have a blame object, which happens to be None since invalid PoP
+        // is self-explainable
+        blame = Some(None);
+        None
+      } else {
+        Some(machine.unwrap())
+      }
+    })
+    .collect::<Vec<_>>();
+
+  test_blame(&commitment_msgs, machines, &secret_shares[&ONE][&TWO].clone(), &blame.unwrap());
+}
+
+#[test]
+fn invalid_ecdh_blame() {
+  let (mut machines, commitment_msgs, _, mut secret_shares) =
+    commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
+
+  // Mutate the share to trigger a blame event
+  // Mutates from 2 to 1, as 1 is expected to end up malicious for test_blame to pass
+  // While here, 2 is malicious, this is so 1 creates the blame proof
+  // We then malleate 1's blame proof, so 1 ends up malicious
+  // Doesn't simply invalidate the PoP as that won't have a blame statement
+  // By mutating the encrypted data, we do ensure a blame statement is created
+  secret_shares
+    .get_mut(&TWO)
+    .unwrap()
+    .get_mut(&ONE)
+    .unwrap()
+    .invalidate_msg(&mut OsRng, CONTEXT, TWO);
+
+  let mut blame = None;
+  let machines = machines
+    .drain()
+    .filter_map(|(i, machine)| {
+      let our_secret_shares = generate_secret_shares(&secret_shares, i);
+      let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
+      if i == ONE {
+        blame = Some(match machine.err() {
+          Some(PedPoPError::InvalidShare { participant: TWO, blame: Some(blame) }) => Some(blame),
+          _ => panic!(),
+        });
+        None
+      } else {
+        Some(machine.unwrap())
+      }
+    })
+    .collect::<Vec<_>>();
+
+  blame.as_mut().unwrap().as_mut().unwrap().invalidate_key();
+  test_blame(&commitment_msgs, machines, &secret_shares[&TWO][&ONE].clone(), &blame.unwrap());
+}
+
+// This should be largely equivalent to the prior test
+#[test]
+fn invalid_dleq_blame() {
+  let (mut machines, commitment_msgs, _, mut secret_shares) =
+    commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
+
+  secret_shares
+    .get_mut(&TWO)
+    .unwrap()
+    .get_mut(&ONE)
+    .unwrap()
+    .invalidate_msg(&mut OsRng, CONTEXT, TWO);
+
+  let mut blame = None;
+  let machines = machines
+    .drain()
+    .filter_map(|(i, machine)| {
+      let our_secret_shares = generate_secret_shares(&secret_shares, i);
+      let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
+      if i == ONE {
+        blame = Some(match machine.err() {
+          Some(PedPoPError::InvalidShare { participant: TWO, blame: Some(blame) }) => Some(blame),
+          _ => panic!(),
+        });
+        None
+      } else {
+        Some(machine.unwrap())
+      }
+    })
+    .collect::<Vec<_>>();
+
+  blame.as_mut().unwrap().as_mut().unwrap().invalidate_dleq();
+  test_blame(&commitment_msgs, machines, &secret_shares[&TWO][&ONE].clone(), &blame.unwrap());
+}
+
+#[test]
+fn invalid_share_serialization_blame() {
+  let (mut machines, commitment_msgs, enc_keys, mut secret_shares) =
+    commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
+
+  secret_shares.get_mut(&ONE).unwrap().get_mut(&TWO).unwrap().invalidate_share_serialization(
+    &mut OsRng,
+    CONTEXT,
+    ONE,
+    enc_keys[&TWO],
+  );
+
+  let mut blame = None;
+  let machines = machines
+    .drain()
+    .filter_map(|(i, machine)| {
+      let our_secret_shares = generate_secret_shares(&secret_shares, i);
+      let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
+      if i == TWO {
+        blame = Some(match machine.err() {
+          Some(PedPoPError::InvalidShare { participant: ONE, blame: Some(blame) }) => Some(blame),
+          _ => panic!(),
+        });
+        None
+      } else {
+        Some(machine.unwrap())
+      }
+    })
+    .collect::<Vec<_>>();
+
+  test_blame(&commitment_msgs, machines, &secret_shares[&ONE][&TWO].clone(), &blame.unwrap());
+}
+
+#[test]
+fn invalid_share_value_blame() {
+  let (mut machines, commitment_msgs, enc_keys, mut secret_shares) =
+    commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
+
+  secret_shares.get_mut(&ONE).unwrap().get_mut(&TWO).unwrap().invalidate_share_value(
+    &mut OsRng,
+    CONTEXT,
+    ONE,
+    enc_keys[&TWO],
+  );
+
+  let mut blame = None;
+  let machines = machines
+    .drain()
+    .filter_map(|(i, machine)| {
+      let our_secret_shares = generate_secret_shares(&secret_shares, i);
+      let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
+      if i == TWO {
+        blame = Some(match machine.err() {
+          Some(PedPoPError::InvalidShare { participant: ONE, blame: Some(blame) }) => Some(blame),
+          _ => panic!(),
+        });
+        None
+      } else {
+        Some(machine.unwrap())
+      }
+    })
+    .collect::<Vec<_>>();
+
+  test_blame(&commitment_msgs, machines, &secret_shares[&ONE][&TWO].clone(), &blame.unwrap());
+}

crypto/dkg/promote/Cargo.toml

@@ -0,0 +1,34 @@
+[package]
+name = "dkg-promote"
+version = "0.6.1"
+description = "Promotions for keys from the dkg crate"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/promote"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+keywords = ["dkg", "multisig", "threshold", "ff", "group"]
+edition = "2021"
+rust-version = "1.80"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+thiserror = { version = "2", default-features = false, features = ["std"] }
+
+rand_core = { version = "0.6", default-features = false, features = ["std"] }
+
+transcript = { package = "flexible-transcript", path = "../../transcript", version = "^0.3.2", default-features = false, features = ["std", "recommended"] }
+ciphersuite = { path = "../../ciphersuite", version = "^0.4.1", default-features = false, features = ["std"] }
+dleq = { path = "../../dleq", version = "^0.4.1", default-features = false, features = ["std", "serialize"] }
+
+dkg = { path = "../", version = "0.6.1", default-features = false, features = ["std"] }
+
+[dev-dependencies]
+zeroize = { version = "^1.5", default-features = false, features = ["std", "zeroize_derive"] }
+rand_core = { version = "0.6", default-features = false, features = ["getrandom"] }
+dalek-ff-group = { path = "../../dalek-ff-group" }
+dkg-recovery = { path = "../recovery", default-features = false, features = ["std"] }

crypto/dkg/promote/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021-2025 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.

crypto/dkg/promote/README.md

@@ -0,0 +1,13 @@
+# Distributed Key Generation - Promote
+
+This crate implements 'promotions' for keys from the
+[`dkg`](https://docs.rs/dkg) crate. A promotion takes a set of keys and maps it
+to a different `Ciphersuite`.
+
+This crate was originally part of the `dkg` crate, which was
+[audited by Cypher Stack in March 2023](
+  https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf
+), culminating in commit
+[669d2dbffc1dafb82a09d9419ea182667115df06](
+  https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06
+). Any subsequent changes have not undergone auditing.

crypto/dkg/promote/src/lib.rs

@@ -1,7 +1,11 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+// This crate requires `dleq` which doesn't support no-std via std-shims
+// #![cfg_attr(not(feature = "std"), no_std)]
+
 use core::{marker::PhantomData, ops::Deref};
 use std::{
   io::{self, Read, Write},
-  sync::Arc,
   collections::HashMap,
 };
 
@@ -12,11 +16,37 @@ use ciphersuite::{group::GroupEncoding, Ciphersuite};
 use transcript::{Transcript, RecommendedTranscript};
 use dleq::DLEqProof;
 
-use crate::{Participant, DkgError, ThresholdCore, ThresholdKeys, validate_map};
+pub use dkg::*;
 
-/// Promote a set of keys to another Ciphersuite definition.
-pub trait CiphersuitePromote<C2: Ciphersuite> {
-  fn promote(self) -> ThresholdKeys<C2>;
+#[cfg(test)]
+mod tests;
+
+/// Errors encountered when promoting keys.
+#[derive(Clone, PartialEq, Eq, Debug, thiserror::Error)]
+pub enum PromotionError {
+  /// Invalid participant identifier.
+  #[error("invalid participant (1 <= participant <= {n}, yet participant is {participant})")]
+  InvalidParticipant {
+    /// The total amount of participants.
+    n: u16,
+    /// The specified participant.
+    participant: Participant,
+  },
+
+  /// An incorrect amount of participants was specified.
+  #[error("incorrect amount of participants. {t} <= amount <= {n}, yet amount is {amount}")]
+  IncorrectAmountOfParticipants {
+    /// The threshold required.
+    t: u16,
+    /// The total amount of participants.
+    n: u16,
+    /// The amount of participants specified.
+    amount: usize,
+  },
+
+  /// Participant provided an invalid proof.
+  #[error("invalid proof {0}")]
+  InvalidProof(Participant),
 }
 
 fn transcript<G: GroupEncoding>(key: &G, i: Participant) -> RecommendedTranscript {
@@ -65,20 +95,21 @@ pub struct GeneratorPromotion<C1: Ciphersuite, C2: Ciphersuite> {
 }
 
 impl<C1: Ciphersuite, C2: Ciphersuite<F = C1::F, G = C1::G>> GeneratorPromotion<C1, C2> {
-  /// Begin promoting keys from one generator to another. Returns a proof this share was properly
-  /// promoted.
+  /// Begin promoting keys from one generator to another.
+  ///
+  /// Returns a proof this share was properly promoted.
   pub fn promote<R: RngCore + CryptoRng>(
     rng: &mut R,
     base: ThresholdKeys<C1>,
   ) -> (GeneratorPromotion<C1, C2>, GeneratorProof<C1>) {
     // Do a DLEqProof for the new generator
     let proof = GeneratorProof {
-      share: C2::generator() * base.secret_share().deref(),
+      share: C2::generator() * base.original_secret_share().deref(),
       proof: DLEqProof::prove(
         rng,
-        &mut transcript(&base.core.group_key(), base.params().i),
+        &mut transcript(&base.original_group_key(), base.params().i()),
         &[C1::generator(), C2::generator()],
-        base.secret_share(),
+        base.original_secret_share(),
       ),
     };
 
@@ -89,35 +120,49 @@ impl<C1: Ciphersuite, C2: Ciphersuite<F = C1::F, G = C1::G>> GeneratorPromotion<
   pub fn complete(
     self,
     proofs: &HashMap<Participant, GeneratorProof<C1>>,
-  ) -> Result<ThresholdKeys<C2>, DkgError<()>> {
+  ) -> Result<ThresholdKeys<C2>, PromotionError> {
     let params = self.base.params();
-    validate_map(proofs, &(1 ..= params.n).map(Participant).collect::<Vec<_>>(), params.i)?;
-
-    let original_shares = self.base.verification_shares();
+    if proofs.len() != (usize::from(params.n()) - 1) {
+      Err(PromotionError::IncorrectAmountOfParticipants {
+        t: params.n(),
+        n: params.n(),
+        amount: proofs.len() + 1,
+      })?;
+    }
+    for i in proofs.keys().copied() {
+      if u16::from(i) > params.n() {
+        Err(PromotionError::InvalidParticipant { n: params.n(), participant: i })?;
+      }
+    }
 
     let mut verification_shares = HashMap::new();
-    verification_shares.insert(params.i, self.proof.share);
-    for (i, proof) in proofs {
-      let i = *i;
+    verification_shares.insert(params.i(), self.proof.share);
+    for i in 1 ..= params.n() {
+      let i = Participant::new(i).unwrap();
+      if i == params.i() {
+        continue;
+      }
+
+      let proof = proofs.get(&i).unwrap();
       proof
         .proof
         .verify(
-          &mut transcript(&self.base.core.group_key(), i),
+          &mut transcript(&self.base.original_group_key(), i),
           &[C1::generator(), C2::generator()],
-          &[original_shares[&i], proof.share],
+          &[self.base.original_verification_share(i), proof.share],
         )
-        .map_err(|_| DkgError::InvalidCommitments(i))?;
+        .map_err(|_| PromotionError::InvalidProof(i))?;
       verification_shares.insert(i, proof.share);
     }
 
-    Ok(ThresholdKeys {
-      core: Arc::new(ThresholdCore::new(
+    Ok(
+      ThresholdKeys::new(
         params,
-        self.base.core.interpolation.clone(),
-        self.base.secret_share().clone(),
+        self.base.interpolation().clone(),
+        self.base.original_secret_share().clone(),
         verification_shares,
-      )),
-      offset: None,
-    })
+      )
+      .unwrap(),
+    )
   }
 }

crypto/dkg/promote/src/tests.rs

@@ -0,0 +1,113 @@
+use core::marker::PhantomData;
+use std::collections::HashMap;
+
+use zeroize::{Zeroize, Zeroizing};
+use rand_core::OsRng;
+
+use dalek_ff_group::Ristretto;
+use ciphersuite::{
+  group::{ff::Field, Group},
+  Ciphersuite,
+};
+
+use dkg::*;
+use dkg_recovery::recover_key;
+use crate::{GeneratorPromotion, GeneratorProof};
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
+struct AltGenerator<C: Ciphersuite> {
+  _curve: PhantomData<C>,
+}
+
+impl<C: Ciphersuite> Ciphersuite for AltGenerator<C> {
+  type F = C::F;
+  type G = C::G;
+  type H = C::H;
+
+  const ID: &'static [u8] = b"Alternate Ciphersuite";
+
+  fn generator() -> Self::G {
+    C::G::generator() * <C as Ciphersuite>::hash_to_F(b"DKG Promotion Test", b"generator")
+  }
+
+  fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
+    <C as Ciphersuite>::hash_to_F(dst, data)
+  }
+}
+
+/// Clone a map without a specific value.
+pub fn clone_without<K: Clone + core::cmp::Eq + core::hash::Hash, V: Clone>(
+  map: &HashMap<K, V>,
+  without: &K,
+) -> HashMap<K, V> {
+  let mut res = map.clone();
+  res.remove(without).unwrap();
+  res
+}
+
+// Test promotion of threshold keys to another generator
+#[test]
+fn test_generator_promotion() {
+  // Generate a set of `ThresholdKeys`
+  const PARTICIPANTS: u16 = 5;
+  let keys: [ThresholdKeys<_>; PARTICIPANTS as usize] = {
+    let shares: [<Ristretto as Ciphersuite>::F; PARTICIPANTS as usize] =
+      core::array::from_fn(|_| <Ristretto as Ciphersuite>::F::random(&mut OsRng));
+    let verification_shares = (0 .. PARTICIPANTS)
+      .map(|i| {
+        (
+          Participant::new(i + 1).unwrap(),
+          <Ristretto as Ciphersuite>::generator() * shares[usize::from(i)],
+        )
+      })
+      .collect::<HashMap<_, _>>();
+    core::array::from_fn(|i| {
+      ThresholdKeys::new(
+        ThresholdParams::new(
+          PARTICIPANTS,
+          PARTICIPANTS,
+          Participant::new(u16::try_from(i + 1).unwrap()).unwrap(),
+        )
+        .unwrap(),
+        Interpolation::Constant(vec![<Ristretto as Ciphersuite>::F::ONE; PARTICIPANTS as usize]),
+        Zeroizing::new(shares[i]),
+        verification_shares.clone(),
+      )
+      .unwrap()
+    })
+  };
+
+  // Perform the promotion
+  let mut promotions = HashMap::new();
+  let mut proofs = HashMap::new();
+  for keys in &keys {
+    let i = keys.params().i();
+    let (promotion, proof) =
+      GeneratorPromotion::<_, AltGenerator<Ristretto>>::promote(&mut OsRng, keys.clone());
+    promotions.insert(i, promotion);
+    proofs.insert(
+      i,
+      GeneratorProof::<Ristretto>::read::<&[u8]>(&mut proof.serialize().as_ref()).unwrap(),
+    );
+  }
+
+  // Complete the promotion, and verify it worked
+  let new_group_key = AltGenerator::<Ristretto>::generator() * *recover_key(&keys).unwrap();
+  for (i, promoting) in promotions.drain() {
+    let promoted = promoting.complete(&clone_without(&proofs, &i)).unwrap();
+    assert_eq!(keys[usize::from(u16::from(i) - 1)].params(), promoted.params());
+    assert_eq!(
+      keys[usize::from(u16::from(i) - 1)].original_secret_share(),
+      promoted.original_secret_share()
+    );
+    assert_eq!(new_group_key, promoted.group_key());
+    for l in 0 .. PARTICIPANTS {
+      let verification_share =
+        promoted.original_verification_share(Participant::new(l + 1).unwrap());
+      assert_eq!(
+        AltGenerator::<Ristretto>::generator() * **keys[usize::from(l)].original_secret_share(),
+        verification_share
+      );
+    }
+  }
+}

crypto/dkg/recovery/Cargo.toml

@@ -0,0 +1,34 @@
+[package]
+name = "dkg-recovery"
+version = "0.6.0"
+description = "Recover a secret-shared key from a collection of dkg::ThresholdKeys"
+license = "MIT"
+repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/recovery"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+keywords = ["dkg", "multisig", "threshold", "ff", "group"]
+edition = "2021"
+rust-version = "1.66"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+zeroize = { version = "^1.5", default-features = false }
+
+thiserror = { version = "2", default-features = false }
+
+ciphersuite = { path = "../../ciphersuite", version = "^0.4.1", default-features = false }
+dkg = { path = "../", version = "0.6", default-features = false }
+
+[features]
+std = [
+  "zeroize/std",
+  "thiserror/std",
+  "ciphersuite/std",
+  "dkg/std",
+]
+default = ["std"]

crypto/dkg/recovery/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021-2025 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.

crypto/dkg/recovery/README.md

@@ -0,0 +1,14 @@
+# Distributed Key Generation - Recovery
+
+A utility function to recover a key from its secret shares.
+
+Keys likely SHOULD NOT ever be recovered, making this primarily intended for
+testing purposes. Instead, the shares of the key should be used to produce
+shares for the desired action, allowing using the key while never
+reconstructing it.
+
+Before being smashed, this crate was [audited by Cypher Stack in March 2023](
+  https://github.com/serai-dex/serai/raw/e1bb2c191b7123fd260d008e31656d090d559d21/audits/Cypher%20Stack%20crypto%20March%202023/Audit.pdf
+), culminating in commit [669d2dbffc1dafb82a09d9419ea182667115df06](
+  https://github.com/serai-dex/serai/tree/669d2dbffc1dafb82a09d9419ea182667115df06
+). Any subsequent changes have not undergone auditing.

crypto/dkg/recovery/src/lib.rs

@@ -0,0 +1,85 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+#![no_std]
+
+use core::ops::{Deref, DerefMut};
+extern crate alloc;
+use alloc::vec::Vec;
+
+use zeroize::Zeroizing;
+
+use ciphersuite::Ciphersuite;
+
+pub use dkg::*;
+
+/// Errors encountered when recovering a secret-shared key from a collection of
+/// `dkg::ThresholdKeys`.
+#[derive(Clone, PartialEq, Eq, Debug, thiserror::Error)]
+pub enum RecoveryError {
+  /// No keys were provided.
+  #[error("no keys provided")]
+  NoKeysProvided,
+  /// Not enough keys were provided.
+  #[error("not enough keys provided (threshold required {required}, provided {provided})")]
+  NotEnoughKeysProvided { required: u16, provided: usize },
+  /// The keys had inconsistent parameters.
+  #[error("keys had inconsistent parameters")]
+  InconsistentParameters,
+  /// The keys are from distinct secret-sharing sessions or otherwise corrupt.
+  #[error("recovery failed")]
+  Failure,
+  /// An error propagated from the underlying `dkg` crate.
+  #[error("error from dkg ({0})")]
+  DkgError(DkgError),
+}
+
+/// Recover a shared secret from a collection of `dkg::ThresholdKeys`.
+pub fn recover_key<C: Ciphersuite>(
+  keys: &[ThresholdKeys<C>],
+) -> Result<Zeroizing<C::F>, RecoveryError> {
+  let included = keys.iter().map(|keys| keys.params().i()).collect::<Vec<_>>();
+
+  let keys_len = keys.len();
+  let mut keys = keys.iter();
+  let first_keys = keys.next().ok_or(RecoveryError::NoKeysProvided)?;
+  {
+    let t = first_keys.params().t();
+    if keys_len < usize::from(t) {
+      Err(RecoveryError::NotEnoughKeysProvided { required: t, provided: keys_len })?;
+    }
+  }
+  {
+    let first_params = (
+      first_keys.params().t(),
+      first_keys.params().n(),
+      first_keys.group_key(),
+      first_keys.current_scalar(),
+      first_keys.current_offset(),
+    );
+    for keys in keys.clone() {
+      let params = (
+        keys.params().t(),
+        keys.params().n(),
+        keys.group_key(),
+        keys.current_scalar(),
+        keys.current_offset(),
+      );
+      if params != first_params {
+        Err(RecoveryError::InconsistentParameters)?;
+      }
+    }
+  }
+
+  let mut res: Zeroizing<_> =
+    first_keys.view(included.clone()).map_err(RecoveryError::DkgError)?.secret_share().clone();
+  for keys in keys {
+    *res.deref_mut() +=
+      keys.view(included.clone()).map_err(RecoveryError::DkgError)?.secret_share().deref();
+  }
+
+  if (C::generator() * res.deref()) != first_keys.group_key() {
+    Err(RecoveryError::Failure)?;
+  }
+
+  Ok(res)
+}

crypto/dkg/src/lib.rs

@@ -2,43 +2,31 @@
 #![doc = include_str!("../README.md")]
 #![cfg_attr(not(feature = "std"), no_std)]
 
-use core::fmt::{self, Debug};
+use core::{
+  ops::Deref,
+  fmt::{self, Debug},
+};
+#[allow(unused_imports)]
+use std_shims::prelude::*;
+use std_shims::{sync::Arc, vec, vec::Vec, collections::HashMap, io};
 
-use thiserror::Error;
+use zeroize::{Zeroize, Zeroizing};
 
-use zeroize::Zeroize;
-
-/// MuSig-style key aggregation.
-pub mod musig;
-
-/// Encryption types and utilities used to secure DKG messages.
-#[cfg(feature = "std")]
-pub mod encryption;
-
-/// The PedPoP distributed key generation protocol described in the
-/// [FROST paper](https://eprint.iacr.org/2020/852), augmented to be verifiable.
-#[cfg(feature = "std")]
-pub mod pedpop;
-
-/// The one-round DKG described in the [eVRF paper](https://eprint.iacr.org/2024/397).
-#[cfg(all(feature = "std", feature = "evrf"))]
-pub mod evrf;
-
-/// Promote keys between ciphersuites.
-#[cfg(feature = "std")]
-pub mod promote;
-
-/// Tests for application-provided curves and algorithms.
-#[cfg(any(test, feature = "tests"))]
-pub mod tests;
+use ciphersuite::{
+  group::{
+    ff::{Field, PrimeField},
+    GroupEncoding,
+  },
+  Ciphersuite,
+};
 
 /// The ID of a participant, defined as a non-zero u16.
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Zeroize)]
 #[cfg_attr(feature = "borsh", derive(borsh::BorshSerialize))]
-pub struct Participant(pub(crate) u16);
+pub struct Participant(u16);
 impl Participant {
   /// Create a new Participant identifier from a u16.
-  pub fn new(i: u16) -> Option<Participant> {
+  pub const fn new(i: u16) -> Option<Participant> {
     if i == 0 {
       None
     } else {
@@ -48,7 +36,7 @@ impl Participant {
 
   /// Convert a Participant identifier to bytes.
   #[allow(clippy::wrong_self_convention)]
-  pub fn to_bytes(&self) -> [u8; 2] {
+  pub const fn to_bytes(&self) -> [u8; 2] {
     self.0.to_le_bytes()
   }
 }
@@ -65,156 +53,177 @@ impl fmt::Display for Participant {
   }
 }
 
-/// Various errors possible during key generation.
-#[derive(Clone, PartialEq, Eq, Debug, Error)]
-pub enum DkgError<B: Clone + PartialEq + Eq + Debug> {
+/// Errors encountered when working with threshold keys.
+#[derive(Clone, PartialEq, Eq, Debug, thiserror::Error)]
+pub enum DkgError {
   /// A parameter was zero.
-  #[cfg_attr(feature = "std", error("a parameter was 0 (threshold {0}, participants {1})"))]
-  ZeroParameter(u16, u16),
+  #[error("a parameter was 0 (threshold {t}, participants {n})")]
+  ZeroParameter {
+    /// The specified threshold.
+    t: u16,
+    /// The specified total amount of participants.
+    n: u16,
+  },
+
   /// The threshold exceeded the amount of participants.
-  #[cfg_attr(feature = "std", error("invalid threshold (max {1}, got {0})"))]
-  InvalidThreshold(u16, u16),
+  #[error("invalid threshold (max {n}, got {t})")]
+  InvalidThreshold {
+    /// The specified threshold.
+    t: u16,
+    /// The specified total amount of participants.
+    n: u16,
+  },
+
   /// Invalid participant identifier.
-  #[cfg_attr(
-    feature = "std",
-    error("invalid participant (0 < participant <= {0}, yet participant is {1})")
-  )]
-  InvalidParticipant(u16, Participant),
+  #[error("invalid participant (1 <= participant <= {n}, yet participant is {participant})")]
+  InvalidParticipant {
+    /// The total amount of participants.
+    n: u16,
+    /// The specified participant.
+    participant: Participant,
+  },
+
+  /// An incorrect amount of participants was specified.
+  #[error("incorrect amount of verification shares (n = {n} yet {shares} provided)")]
+  IncorrectAmountOfVerificationShares {
+    /// The amount of participants.
+    n: u16,
+    /// The amount of shares provided.
+    shares: usize,
+  },
+
+  /// An inapplicable method of interpolation was specified.
+  #[error("inapplicable method of interpolation ({0})")]
+  InapplicableInterpolation(&'static str),
+
+  /// An incorrect amount of participants was specified.
+  #[error("incorrect amount of participants. {t} <= amount <= {n}, yet amount is {amount}")]
+  IncorrectAmountOfParticipants {
+    /// The threshold required.
+    t: u16,
+    /// The total amount of participants.
+    n: u16,
+    /// The amount of participants specified.
+    amount: usize,
+  },
 
-  /// Invalid signing set.
-  #[cfg_attr(feature = "std", error("invalid signing set"))]
-  InvalidSigningSet,
-  /// Invalid amount of participants.
-  #[cfg_attr(feature = "std", error("invalid participant quantity (expected {0}, got {1})"))]
-  InvalidParticipantQuantity(usize, usize),
   /// A participant was duplicated.
-  #[cfg_attr(feature = "std", error("duplicated participant ({0})"))]
+  #[error("a participant ({0}) was duplicated")]
   DuplicatedParticipant(Participant),
-  /// A participant was missing.
-  #[cfg_attr(feature = "std", error("missing participant {0}"))]
-  MissingParticipant(Participant),
 
-  /// An invalid proof of knowledge was provided.
-  #[cfg_attr(feature = "std", error("invalid proof of knowledge (participant {0})"))]
-  InvalidCommitments(Participant),
-  /// An invalid DKG share was provided.
-  #[cfg_attr(feature = "std", error("invalid share (participant {participant}, blame {blame})"))]
-  InvalidShare { participant: Participant, blame: Option<B> },
+  /// Not participating in declared signing set.
+  #[error("not participating in declared signing set")]
+  NotParticipating,
 }
 
-#[cfg(feature = "std")]
-mod lib {
-  pub use super::*;
-
-  use core::ops::Deref;
-  use std::{io, sync::Arc, collections::HashMap};
-
-  use zeroize::Zeroizing;
-
-  use ciphersuite::{
-    group::{
-      ff::{Field, PrimeField},
-      GroupEncoding,
-    },
-    Ciphersuite,
-  };
-
-  #[cfg(feature = "borsh")]
-  impl borsh::BorshDeserialize for Participant {
+// Manually implements BorshDeserialize so we can enforce it's a valid index
+#[cfg(feature = "borsh")]
+impl borsh::BorshDeserialize for Participant {
   fn deserialize_reader<R: io::Read>(reader: &mut R) -> io::Result<Self> {
     Participant::new(u16::deserialize_reader(reader)?)
       .ok_or_else(|| io::Error::other("invalid participant"))
   }
-  }
+}
 
-  // Validate a map of values to have the expected included participants
-  pub(crate) fn validate_map<T, B: Clone + PartialEq + Eq + Debug>(
-    map: &HashMap<Participant, T>,
-    included: &[Participant],
-    ours: Participant,
-  ) -> Result<(), DkgError<B>> {
-    if (map.len() + 1) != included.len() {
-      Err(DkgError::InvalidParticipantQuantity(included.len(), map.len() + 1))?;
-    }
-
-    for included in included {
-      if *included == ours {
-        if map.contains_key(included) {
-          Err(DkgError::DuplicatedParticipant(*included))?;
-        }
-        continue;
-      }
-
-      if !map.contains_key(included) {
-        Err(DkgError::MissingParticipant(*included))?;
-      }
-    }
-
-    Ok(())
-  }
-
-  /// Parameters for a multisig.
-  // These fields should not be made public as they should be static
-  #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
-  #[cfg_attr(feature = "borsh", derive(borsh::BorshSerialize))]
-  pub struct ThresholdParams {
+/// Parameters for a multisig.
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
+#[cfg_attr(feature = "borsh", derive(borsh::BorshSerialize))]
+pub struct ThresholdParams {
   /// Participants needed to sign on behalf of the group.
-    pub(crate) t: u16,
+  t: u16,
   /// Amount of participants.
-    pub(crate) n: u16,
+  n: u16,
   /// Index of the participant being acted for.
-    pub(crate) i: Participant,
+  i: Participant,
+}
+
+/// An iterator over all participant indexes.
+struct AllParticipantIndexes {
+  i: u16,
+  n: u16,
+}
+impl Iterator for AllParticipantIndexes {
+  type Item = Participant;
+  fn next(&mut self) -> Option<Participant> {
+    if self.i > self.n {
+      None?;
+    }
+    let res = Participant::new(self.i).unwrap();
+
+    // If i == n == u16::MAX, we cause `i > n` by setting `n` to `0` so the iterator becomes empty
+    if self.i == u16::MAX {
+      self.n = 0;
+    } else {
+      self.i += 1;
     }
 
-  impl ThresholdParams {
+    Some(res)
+  }
+}
+
+impl ThresholdParams {
   /// Create a new set of parameters.
-    pub fn new(t: u16, n: u16, i: Participant) -> Result<ThresholdParams, DkgError<()>> {
+  pub const fn new(t: u16, n: u16, i: Participant) -> Result<ThresholdParams, DkgError> {
     if (t == 0) || (n == 0) {
-        Err(DkgError::ZeroParameter(t, n))?;
+      return Err(DkgError::ZeroParameter { t, n });
     }
 
     if t > n {
-        Err(DkgError::InvalidThreshold(t, n))?;
+      return Err(DkgError::InvalidThreshold { t, n });
     }
-      if u16::from(i) > n {
-        Err(DkgError::InvalidParticipant(n, i))?;
+    if i.0 > n {
+      return Err(DkgError::InvalidParticipant { n, participant: i });
     }
 
     Ok(ThresholdParams { t, n, i })
   }
 
-    /// Return the threshold for a multisig with these parameters.
-    pub fn t(&self) -> u16 {
+  /// The threshold for a multisig with these parameters.
+  pub const fn t(&self) -> u16 {
     self.t
   }
-    /// Return the amount of participants for a multisig with these parameters.
-    pub fn n(&self) -> u16 {
+  /// The amount of participants for a multisig with these parameters.
+  pub const fn n(&self) -> u16 {
     self.n
   }
-    /// Return the participant index of the share with these parameters.
-    pub fn i(&self) -> Participant {
+  /// The participant index of the share with these parameters.
+  pub const fn i(&self) -> Participant {
     self.i
   }
-  }
 
-  #[cfg(feature = "borsh")]
-  impl borsh::BorshDeserialize for ThresholdParams {
+  /// An iterator over all participant indexes.
+  pub fn all_participant_indexes(&self) -> impl Iterator<Item = Participant> {
+    AllParticipantIndexes { i: 1, n: self.n }
+  }
+}
+
+#[cfg(feature = "borsh")]
+impl borsh::BorshDeserialize for ThresholdParams {
   fn deserialize_reader<R: io::Read>(reader: &mut R) -> io::Result<Self> {
     let t = u16::deserialize_reader(reader)?;
     let n = u16::deserialize_reader(reader)?;
     let i = Participant::deserialize_reader(reader)?;
     ThresholdParams::new(t, n, i).map_err(|e| io::Error::other(format!("{e:?}")))
   }
-  }
+}
 
-  #[derive(Clone, PartialEq, Eq, Debug, Zeroize)]
-  pub(crate) enum Interpolation<F: Zeroize + PrimeField> {
+/// A method of interpolation.
+#[derive(Clone, PartialEq, Eq, Debug, Zeroize)]
+pub enum Interpolation<F: Zeroize + PrimeField> {
+  /// A list of constant coefficients, one for each of the secret key shares.
+  /*
+    There's no benefit to using a full linear combination here, as the additive term would have
+    an entirely known evaluation with a fixed, public coefficient of `1`. Accordingly, the entire
+    key can simply be offset with the additive term to achieve the same effect.
+  */
   Constant(Vec<F>),
+  /// Lagrange interpolation.
   Lagrange,
-  }
+}
 
-  impl<F: Zeroize + PrimeField> Interpolation<F> {
-    pub(crate) fn interpolation_factor(&self, i: Participant, included: &[Participant]) -> F {
+impl<F: Zeroize + PrimeField> Interpolation<F> {
+  /// The interpolation factor for this participant, within this signing set.
+  fn interpolation_factor(&self, i: Participant, included: &[Participant]) -> F {
     match self {
       Interpolation::Constant(c) => c[usize::from(u16::from(i) - 1)],
       Interpolation::Lagrange => {
@@ -238,89 +247,301 @@ mod lib {
       }
     }
   }
-  }
+}
 
-  /// Keys and verification shares generated by a DKG.
-  /// Called core as they're expected to be wrapped into an Arc before usage in various operations.
-  #[derive(Clone, PartialEq, Eq)]
-  pub struct ThresholdCore<C: Ciphersuite> {
-    /// Threshold Parameters.
-    pub(crate) params: ThresholdParams,
-    /// The interpolation method used.
-    pub(crate) interpolation: Interpolation<C::F>,
+/// A key share for a thresholdized secret key.
+///
+/// This is the 'core' structure containing all relevant data, expected to be wrapped into an
+/// heap-allocated pointer to minimize copies on the stack (`ThresholdKeys`, the publicly exposed
+/// type).
+#[derive(Clone, PartialEq, Eq)]
+struct ThresholdCore<C: Ciphersuite> {
+  params: ThresholdParams,
+  group_key: C::G,
+  verification_shares: HashMap<Participant, C::G>,
+  interpolation: Interpolation<C::F>,
+  secret_share: Zeroizing<C::F>,
+}
 
-    /// Secret share key.
-    pub(crate) secret_share: Zeroizing<C::F>,
-    /// Group key.
-    pub(crate) group_key: C::G,
-    /// Verification shares.
-    pub(crate) verification_shares: HashMap<Participant, C::G>,
-  }
-
-  impl<C: Ciphersuite> fmt::Debug for ThresholdCore<C> {
+impl<C: Ciphersuite> fmt::Debug for ThresholdCore<C> {
   fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
     fmt
       .debug_struct("ThresholdCore")
       .field("params", &self.params)
-        .field("interpolation", &self.interpolation)
       .field("group_key", &self.group_key)
       .field("verification_shares", &self.verification_shares)
+      .field("interpolation", &self.interpolation)
       .finish_non_exhaustive()
   }
-  }
+}
 
-  impl<C: Ciphersuite> Zeroize for ThresholdCore<C> {
+impl<C: Ciphersuite> Zeroize for ThresholdCore<C> {
   fn zeroize(&mut self) {
     self.params.zeroize();
-      self.interpolation.zeroize();
-      self.secret_share.zeroize();
     self.group_key.zeroize();
     for share in self.verification_shares.values_mut() {
       share.zeroize();
     }
+    self.interpolation.zeroize();
+    self.secret_share.zeroize();
   }
-  }
+}
 
-  impl<C: Ciphersuite> ThresholdCore<C> {
-    pub(crate) fn new(
+/// Threshold keys usable for signing.
+#[derive(Clone, Debug, Zeroize)]
+pub struct ThresholdKeys<C: Ciphersuite> {
+  // Core keys.
+  #[zeroize(skip)]
+  core: Arc<Zeroizing<ThresholdCore<C>>>,
+
+  // Scalar applied to these keys.
+  scalar: C::F,
+  // Offset applied to these keys.
+  offset: C::F,
+}
+
+/// View of keys, interpolated and with the expected linear combination taken for usage.
+#[derive(Clone)]
+pub struct ThresholdView<C: Ciphersuite> {
+  interpolation: Interpolation<C::F>,
+  scalar: C::F,
+  offset: C::F,
+  group_key: C::G,
+  included: Vec<Participant>,
+  secret_share: Zeroizing<C::F>,
+  original_verification_shares: HashMap<Participant, C::G>,
+  verification_shares: HashMap<Participant, C::G>,
+}
+
+impl<C: Ciphersuite> fmt::Debug for ThresholdView<C> {
+  fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fmt
+      .debug_struct("ThresholdView")
+      .field("interpolation", &self.interpolation)
+      .field("scalar", &self.scalar)
+      .field("offset", &self.offset)
+      .field("group_key", &self.group_key)
+      .field("included", &self.included)
+      .field("original_verification_shares", &self.original_verification_shares)
+      .field("verification_shares", &self.verification_shares)
+      .finish_non_exhaustive()
+  }
+}
+
+impl<C: Ciphersuite> Zeroize for ThresholdView<C> {
+  fn zeroize(&mut self) {
+    self.scalar.zeroize();
+    self.offset.zeroize();
+    self.group_key.zeroize();
+    self.included.zeroize();
+    self.secret_share.zeroize();
+    for share in self.original_verification_shares.values_mut() {
+      share.zeroize();
+    }
+    for share in self.verification_shares.values_mut() {
+      share.zeroize();
+    }
+  }
+}
+
+impl<C: Ciphersuite> ThresholdKeys<C> {
+  /// Create a new set of ThresholdKeys.
+  pub fn new(
     params: ThresholdParams,
     interpolation: Interpolation<C::F>,
     secret_share: Zeroizing<C::F>,
     verification_shares: HashMap<Participant, C::G>,
-    ) -> ThresholdCore<C> {
+  ) -> Result<ThresholdKeys<C>, DkgError> {
+    if verification_shares.len() != usize::from(params.n()) {
+      Err(DkgError::IncorrectAmountOfVerificationShares {
+        n: params.n(),
+        shares: verification_shares.len(),
+      })?;
+    }
+    for participant in verification_shares.keys().copied() {
+      if u16::from(participant) > params.n() {
+        Err(DkgError::InvalidParticipant { n: params.n(), participant })?;
+      }
+    }
+
+    match &interpolation {
+      Interpolation::Constant(_) => {
+        if params.t() != params.n() {
+          Err(DkgError::InapplicableInterpolation("constant interpolation for keys where t != n"))?;
+        }
+      }
+      Interpolation::Lagrange => {}
+    }
+
     let t = (1 ..= params.t()).map(Participant).collect::<Vec<_>>();
     let group_key =
       t.iter().map(|i| verification_shares[i] * interpolation.interpolation_factor(*i, &t)).sum();
-      ThresholdCore { params, interpolation, secret_share, group_key, verification_shares }
+
+    Ok(ThresholdKeys {
+      core: Arc::new(Zeroizing::new(ThresholdCore {
+        params,
+        interpolation,
+        secret_share,
+        group_key,
+        verification_shares,
+      })),
+      scalar: C::F::ONE,
+      offset: C::F::ZERO,
+    })
   }
 
-    /// Parameters for these keys.
+  /// Scale the keys by a given scalar to allow for various account and privacy schemes.
+  ///
+  /// This scalar is ephemeral and will not be included when these keys are serialized. The
+  /// scalar is applied on top of any already-existing scalar/offset.
+  ///
+  /// Returns `None` if the scalar is equal to `0`.
+  #[must_use]
+  pub fn scale(mut self, scalar: C::F) -> Option<ThresholdKeys<C>> {
+    if bool::from(scalar.is_zero()) {
+      None?;
+    }
+    self.scalar *= scalar;
+    self.offset *= scalar;
+    Some(self)
+  }
+
+  /// Offset the keys by a given scalar to allow for various account and privacy schemes.
+  ///
+  /// This offset is ephemeral and will not be included when these keys are serialized. The
+  /// offset is applied on top of any already-existing scalar/offset.
+  #[must_use]
+  pub fn offset(mut self, offset: C::F) -> ThresholdKeys<C> {
+    self.offset += offset;
+    self
+  }
+
+  /// Return the current scalar in-use for these keys.
+  pub fn current_scalar(&self) -> C::F {
+    self.scalar
+  }
+
+  /// Return the current offset in-use for these keys.
+  pub fn current_offset(&self) -> C::F {
+    self.offset
+  }
+
+  /// Return the parameters for these keys.
   pub fn params(&self) -> ThresholdParams {
-      self.params
+    self.core.params
   }
 
-    /// Secret share for these keys.
-    pub fn secret_share(&self) -> &Zeroizing<C::F> {
-      &self.secret_share
+  /// Return the original group key, without any tweaks applied.
+  pub fn original_group_key(&self) -> C::G {
+    self.core.group_key
   }
 
-    /// Group key for these keys.
+  /// Return the interpolation method for these keys.
+  pub fn interpolation(&self) -> &Interpolation<C::F> {
+    &self.core.interpolation
+  }
+
+  /// Return the group key, with the expected linear combination taken.
   pub fn group_key(&self) -> C::G {
-      self.group_key
+    (self.core.group_key * self.scalar) + (C::generator() * self.offset)
   }
 
-    pub(crate) fn verification_shares(&self) -> HashMap<Participant, C::G> {
-      self.verification_shares.clone()
+  /// Return the underlying secret share for these keys, without any tweaks applied.
+  pub fn original_secret_share(&self) -> &Zeroizing<C::F> {
+    &self.core.secret_share
   }
 
-    /// Write these keys to a type satisfying std::io::Write.
+  /// Return the original (untweaked) verification share for the specified participant.
+  ///
+  /// This will panic if the participant index is invalid for these keys.
+  pub fn original_verification_share(&self, l: Participant) -> C::G {
+    self.core.verification_shares[&l]
+  }
+
+  /// Obtain a view of these keys, interpolated for the specified signing set, with the specified
+  /// linear combination taken.
+  pub fn view(&self, mut included: Vec<Participant>) -> Result<ThresholdView<C>, DkgError> {
+    if (included.len() < self.params().t.into()) ||
+      (usize::from(self.params().n()) < included.len())
+    {
+      Err(DkgError::IncorrectAmountOfParticipants {
+        t: self.params().t,
+        n: self.params().n,
+        amount: included.len(),
+      })?;
+    }
+    included.sort();
+    {
+      let mut found = included[0] == self.params().i();
+      for i in 1 .. included.len() {
+        if included[i - 1] == included[i] {
+          Err(DkgError::DuplicatedParticipant(included[i]))?;
+        }
+        found |= included[i] == self.params().i();
+      }
+      if !found {
+        Err(DkgError::NotParticipating)?;
+      }
+    }
+    {
+      let last = *included.last().unwrap();
+      if u16::from(last) > self.params().n() {
+        Err(DkgError::InvalidParticipant { n: self.params().n(), participant: last })?;
+      }
+    }
+
+    // The interpolation occurs multiplicatively, letting us scale by the scalar now
+    let secret_share_scaled = Zeroizing::new(self.scalar * self.original_secret_share().deref());
+    let mut secret_share = Zeroizing::new(
+      self.core.interpolation.interpolation_factor(self.params().i(), &included) *
+        secret_share_scaled.deref(),
+    );
+
+    let mut verification_shares = HashMap::with_capacity(included.len());
+    for i in &included {
+      let verification_share = self.core.verification_shares[i];
+      let verification_share = verification_share *
+        self.scalar *
+        self.core.interpolation.interpolation_factor(*i, &included);
+      verification_shares.insert(*i, verification_share);
+    }
+
+    /*
+      The offset is included by adding it to the participant with the lowest ID.
+
+      This is done after interpolating to ensure, regardless of the method of interpolation, that
+      the method of interpolation does not scale the offset. For Lagrange interpolation, we could
+      add the offset to every key share before interpolating, yet for Constant interpolation, we
+      _have_ to add it as we do here (which also works even when we intend to perform Lagrange
+      interpolation).
+    */
+    if included[0] == self.params().i() {
+      *secret_share += self.offset;
+    }
+    *verification_shares.get_mut(&included[0]).unwrap() += C::generator() * self.offset;
+
+    Ok(ThresholdView {
+      interpolation: self.core.interpolation.clone(),
+      scalar: self.scalar,
+      offset: self.offset,
+      group_key: self.group_key(),
+      secret_share,
+      original_verification_shares: self.core.verification_shares.clone(),
+      verification_shares,
+      included,
+    })
+  }
+
+  /// Write these keys to a type satisfying `std::io::Write`.
+  ///
+  /// This will not include the ephemeral scalar/offset.
   pub fn write<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
     writer.write_all(&u32::try_from(C::ID.len()).unwrap().to_le_bytes())?;
     writer.write_all(C::ID)?;
-      writer.write_all(&self.params.t.to_le_bytes())?;
-      writer.write_all(&self.params.n.to_le_bytes())?;
-      writer.write_all(&self.params.i.to_bytes())?;
-      match &self.interpolation {
+    writer.write_all(&self.core.params.t.to_le_bytes())?;
+    writer.write_all(&self.core.params.n.to_le_bytes())?;
+    writer.write_all(&self.core.params.i.to_bytes())?;
+    match &self.core.interpolation {
       Interpolation::Constant(c) => {
         writer.write_all(&[0])?;
         for c in c {
@@ -329,27 +550,30 @@ mod lib {
       }
       Interpolation::Lagrange => writer.write_all(&[1])?,
     };
-      let mut share_bytes = self.secret_share.to_repr();
+    let mut share_bytes = self.core.secret_share.to_repr();
     writer.write_all(share_bytes.as_ref())?;
     share_bytes.as_mut().zeroize();
-      for l in 1 ..= self.params.n {
-        writer
-          .write_all(self.verification_shares[&Participant::new(l).unwrap()].to_bytes().as_ref())?;
+    for l in 1 ..= self.core.params.n {
+      writer.write_all(
+        self.core.verification_shares[&Participant::new(l).unwrap()].to_bytes().as_ref(),
+      )?;
     }
     Ok(())
   }
 
   /// Serialize these keys to a `Vec<u8>`.
+  ///
+  /// This will not include the ephemeral scalar/offset.
   pub fn serialize(&self) -> Zeroizing<Vec<u8>> {
     let mut serialized = Zeroizing::new(vec![]);
     self.write::<Vec<u8>>(serialized.as_mut()).unwrap();
     serialized
   }
 
-    /// Read keys from a type satisfying std::io::Read.
-    pub fn read<R: io::Read>(reader: &mut R) -> io::Result<ThresholdCore<C>> {
+  /// Read keys from a type satisfying `std::io::Read`.
+  pub fn read<R: io::Read>(reader: &mut R) -> io::Result<ThresholdKeys<C>> {
     {
-        let different = || io::Error::other("deserializing ThresholdCore for another curve");
+      let different = || io::Error::other("deserializing ThresholdKeys for another curve");
 
       let mut id_len = [0; 4];
       reader.read_exact(&mut id_len)?;
@@ -398,166 +622,23 @@ mod lib {
       verification_shares.insert(l, <C as Ciphersuite>::read_G(reader)?);
     }
 
-      Ok(ThresholdCore::new(
-        ThresholdParams::new(t, n, i).map_err(|_| io::Error::other("invalid parameters"))?,
+    ThresholdKeys::new(
+      ThresholdParams::new(t, n, i).map_err(io::Error::other)?,
       interpolation,
       secret_share,
       verification_shares,
-      ))
+    )
+    .map_err(io::Error::other)
   }
+}
+
+impl<C: Ciphersuite> ThresholdView<C> {
+  /// Return the scalar applied to this view.
+  pub fn scalar(&self) -> C::F {
+    self.scalar
   }
 
-  /// Threshold keys usable for signing.
-  #[derive(Clone, Debug, Zeroize)]
-  pub struct ThresholdKeys<C: Ciphersuite> {
-    // Core keys.
-    // If this is the last reference, the underlying keys will be dropped. When that happens, the
-    // private key present within it will be zeroed out (as it's within Zeroizing).
-    #[zeroize(skip)]
-    pub(crate) core: Arc<ThresholdCore<C>>,
-
-    // Offset applied to these keys.
-    pub(crate) offset: Option<C::F>,
-  }
-
-  /// View of keys, interpolated and offset for usage.
-  #[derive(Clone)]
-  pub struct ThresholdView<C: Ciphersuite> {
-    interpolation: Interpolation<C::F>,
-    offset: C::F,
-    group_key: C::G,
-    included: Vec<Participant>,
-    secret_share: Zeroizing<C::F>,
-    original_verification_shares: HashMap<Participant, C::G>,
-    verification_shares: HashMap<Participant, C::G>,
-  }
-
-  impl<C: Ciphersuite> fmt::Debug for ThresholdView<C> {
-    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
-      fmt
-        .debug_struct("ThresholdView")
-        .field("interpolation", &self.interpolation)
-        .field("offset", &self.offset)
-        .field("group_key", &self.group_key)
-        .field("included", &self.included)
-        .field("original_verification_shares", &self.original_verification_shares)
-        .field("verification_shares", &self.verification_shares)
-        .finish_non_exhaustive()
-    }
-  }
-
-  impl<C: Ciphersuite> Zeroize for ThresholdView<C> {
-    fn zeroize(&mut self) {
-      self.offset.zeroize();
-      self.group_key.zeroize();
-      self.included.zeroize();
-      self.secret_share.zeroize();
-      for share in self.original_verification_shares.values_mut() {
-        share.zeroize();
-      }
-      for share in self.verification_shares.values_mut() {
-        share.zeroize();
-      }
-    }
-  }
-
-  impl<C: Ciphersuite> ThresholdKeys<C> {
-    /// Create a new set of ThresholdKeys from a ThresholdCore.
-    pub fn new(core: ThresholdCore<C>) -> ThresholdKeys<C> {
-      ThresholdKeys { core: Arc::new(core), offset: None }
-    }
-
-    /// Offset the keys by a given scalar to allow for various account and privacy schemes.
-    ///
-    /// This offset is ephemeral and will not be included when these keys are serialized. It also
-    /// accumulates, so calling offset multiple times will produce a offset of the offsets' sum.
-    #[must_use]
-    pub fn offset(&self, offset: C::F) -> ThresholdKeys<C> {
-      let mut res = self.clone();
-      // Carry any existing offset
-      // Enables schemes like Monero's subaddresses which have a per-subaddress offset and then a
-      // one-time-key offset
-      res.offset = Some(offset + res.offset.unwrap_or(C::F::ZERO));
-      res
-    }
-
-    /// Return the current offset in-use for these keys.
-    pub fn current_offset(&self) -> Option<C::F> {
-      self.offset
-    }
-
-    /// Return the parameters for these keys.
-    pub fn params(&self) -> ThresholdParams {
-      self.core.params
-    }
-
-    /// Return the secret share for these keys.
-    pub fn secret_share(&self) -> &Zeroizing<C::F> {
-      &self.core.secret_share
-    }
-
-    /// Return the group key, with any offset applied.
-    pub fn group_key(&self) -> C::G {
-      self.core.group_key + (C::generator() * self.offset.unwrap_or(C::F::ZERO))
-    }
-
-    /// Return all participants' verification shares without any offsetting.
-    pub(crate) fn verification_shares(&self) -> HashMap<Participant, C::G> {
-      self.core.verification_shares()
-    }
-
-    /// Serialize these keys to a `Vec<u8>`.
-    pub fn serialize(&self) -> Zeroizing<Vec<u8>> {
-      self.core.serialize()
-    }
-
-    /// Obtain a view of these keys, with any offset applied, interpolated for the specified signing
-    /// set.
-    pub fn view(&self, mut included: Vec<Participant>) -> Result<ThresholdView<C>, DkgError<()>> {
-      if (included.len() < self.params().t.into()) ||
-        (usize::from(self.params().n()) < included.len())
-      {
-        Err(DkgError::InvalidSigningSet)?;
-      }
-      included.sort();
-
-      let mut secret_share = Zeroizing::new(
-        self.core.interpolation.interpolation_factor(self.params().i(), &included) *
-          self.secret_share().deref(),
-      );
-
-      let mut verification_shares = self.verification_shares();
-      for (i, share) in &mut verification_shares {
-        *share *= self.core.interpolation.interpolation_factor(*i, &included);
-      }
-
-      // The offset is included by adding it to the participant with the lowest ID
-      let offset = self.offset.unwrap_or(C::F::ZERO);
-      if included[0] == self.params().i() {
-        *secret_share += offset;
-      }
-      *verification_shares.get_mut(&included[0]).unwrap() += C::generator() * offset;
-
-      Ok(ThresholdView {
-        interpolation: self.core.interpolation.clone(),
-        offset,
-        group_key: self.group_key(),
-        secret_share,
-        original_verification_shares: self.verification_shares(),
-        verification_shares,
-        included,
-      })
-    }
-  }
-
-  impl<C: Ciphersuite> From<ThresholdCore<C>> for ThresholdKeys<C> {
-    fn from(keys: ThresholdCore<C>) -> ThresholdKeys<C> {
-      ThresholdKeys::new(keys)
-    }
-  }
-
-  impl<C: Ciphersuite> ThresholdView<C> {
-    /// Return the offset for this view.
+  /// Return the offset applied to this view.
   pub fn offset(&self) -> C::F {
     self.offset
   }
@@ -580,21 +661,23 @@ mod lib {
     Some(self.interpolation.interpolation_factor(participant, &self.included))
   }
 
-    /// Return the interpolated, offset secret share.
+  /// Return the interpolated secret share, with the expected linear combination taken.
   pub fn secret_share(&self) -> &Zeroizing<C::F> {
     &self.secret_share
   }
 
-    /// Return the original verification share for the specified participant.
+  /// Return the original (untweaked) verification share for the specified participant.
+  ///
+  /// This will panic if the participant index is invalid for these keys.
   pub fn original_verification_share(&self, l: Participant) -> C::G {
     self.original_verification_shares[&l]
   }
 
-    /// Return the interpolated, offset verification share for the specified participant.
+  /// Return the interpolated verification share, with the expected linear combination taken,
+  /// for the specified participant.
+  ///
+  /// This will panic if the participant was not included in the signing set.
   pub fn verification_share(&self, l: Participant) -> C::G {
     self.verification_shares[&l]
   }
-  }
 }
-#[cfg(feature = "std")]
-pub use lib::*;

crypto/dkg/src/musig.rs

@@ -1,128 +0,0 @@
-#[cfg(feature = "std")]
-use core::ops::Deref;
-use std_shims::{vec, vec::Vec, collections::HashSet};
-#[cfg(feature = "std")]
-use std_shims::collections::HashMap;
-
-#[cfg(feature = "std")]
-use zeroize::Zeroizing;
-
-use ciphersuite::{
-  group::{Group, GroupEncoding},
-  Ciphersuite,
-};
-
-use crate::DkgError;
-#[cfg(feature = "std")]
-use crate::{Participant, ThresholdParams, Interpolation, ThresholdCore};
-
-fn check_keys<C: Ciphersuite>(keys: &[C::G]) -> Result<u16, DkgError<()>> {
-  if keys.is_empty() {
-    Err(DkgError::InvalidSigningSet)?;
-  }
-  // Too many signers
-  let keys_len = u16::try_from(keys.len()).map_err(|_| DkgError::InvalidSigningSet)?;
-
-  // Duplicated public keys
-  if keys.iter().map(|key| key.to_bytes().as_ref().to_vec()).collect::<HashSet<_>>().len() !=
-    keys.len()
-  {
-    Err(DkgError::InvalidSigningSet)?;
-  }
-
-  Ok(keys_len)
-}
-
-// This function panics if called with keys whose length exceed 2**16.
-// This is fine since it's internal and all calls occur after calling check_keys, which does check
-// the keys' length.
-fn binding_factor_transcript<C: Ciphersuite>(
-  context: &[u8],
-  keys: &[C::G],
-) -> Result<Vec<u8>, DkgError<()>> {
-  let mut transcript = vec![];
-  transcript.push(u8::try_from(context.len()).map_err(|_| DkgError::InvalidSigningSet)?);
-  transcript.extend(context);
-  transcript.extend(u16::try_from(keys.len()).unwrap().to_le_bytes());
-  for key in keys {
-    transcript.extend(key.to_bytes().as_ref());
-  }
-  Ok(transcript)
-}
-
-fn binding_factor<C: Ciphersuite>(mut transcript: Vec<u8>, i: u16) -> C::F {
-  transcript.extend(i.to_le_bytes());
-  C::hash_to_F(b"musig", &transcript)
-}
-
-/// The group key resulting from using this library's MuSig key gen.
-///
-/// This function will return an error if the context is longer than 255 bytes.
-///
-/// Creating an aggregate key with a list containing duplicated public keys will return an error.
-pub fn musig_key<C: Ciphersuite>(context: &[u8], keys: &[C::G]) -> Result<C::G, DkgError<()>> {
-  let keys_len = check_keys::<C>(keys)?;
-  let transcript = binding_factor_transcript::<C>(context, keys)?;
-  let mut res = C::G::identity();
-  for i in 1 ..= keys_len {
-    // TODO: Calculate this with a multiexp
-    res += keys[usize::from(i - 1)] * binding_factor::<C>(transcript.clone(), i);
-  }
-  Ok(res)
-}
-
-/// A n-of-n non-interactive DKG which does not guarantee the usability of the resulting key.
-///
-/// Creating an aggregate key with a list containing duplicated public keys returns an error.
-#[cfg(feature = "std")]
-pub fn musig<C: Ciphersuite>(
-  context: &[u8],
-  private_key: &Zeroizing<C::F>,
-  keys: &[C::G],
-) -> Result<ThresholdCore<C>, DkgError<()>> {
-  let keys_len = check_keys::<C>(keys)?;
-
-  let our_pub_key = C::generator() * private_key.deref();
-  let Some(pos) = keys.iter().position(|key| *key == our_pub_key) else {
-    // Not present in signing set
-    Err(DkgError::InvalidSigningSet)?
-  };
-  let params = ThresholdParams::new(
-    keys_len,
-    keys_len,
-    // These errors shouldn't be possible, as pos is bounded to len - 1
-    // Since len is prior guaranteed to be within u16::MAX, pos + 1 must also be
-    Participant::new((pos + 1).try_into().map_err(|_| DkgError::InvalidSigningSet)?)
-      .ok_or(DkgError::InvalidSigningSet)?,
-  )?;
-
-  // Calculate the binding factor per-key
-  let transcript = binding_factor_transcript::<C>(context, keys)?;
-  let mut binding = Vec::with_capacity(keys.len());
-  for i in 1 ..= keys_len {
-    binding.push(binding_factor::<C>(transcript.clone(), i));
-  }
-
-  // Our secret share is our private key
-  let secret_share = private_key.clone();
-
-  // Calculate verification shares
-  let mut verification_shares = HashMap::new();
-  let mut group_key = C::G::identity();
-  for l in 1 ..= keys_len {
-    let key = keys[usize::from(l) - 1];
-    group_key += key * binding[usize::from(l - 1)];
-
-    // These errors also shouldn't be possible, for the same reasons as documented above
-    verification_shares.insert(Participant::new(l).ok_or(DkgError::InvalidSigningSet)?, key);
-  }
-  debug_assert_eq!(C::generator() * secret_share.deref(), verification_shares[&params.i()]);
-  debug_assert_eq!(musig_key::<C>(context, keys).unwrap(), group_key);
-
-  Ok(ThresholdCore::new(
-    params,
-    Interpolation::Constant(binding),
-    secret_share,
-    verification_shares,
-  ))
-}

crypto/dkg/src/tests/mod.rs

@@ -1,105 +0,0 @@
-use core::ops::Deref;
-use std::collections::HashMap;
-
-use zeroize::Zeroizing;
-use rand_core::{RngCore, CryptoRng};
-
-use ciphersuite::{group::ff::Field, Ciphersuite};
-
-use crate::{Participant, ThresholdCore, ThresholdKeys, musig::musig as musig_fn};
-
-mod musig;
-pub use musig::test_musig;
-
-/// FROST key generation testing utility.
-pub mod pedpop;
-use pedpop::pedpop_gen;
-
-// Promotion test.
-mod promote;
-use promote::test_generator_promotion;
-
-#[cfg(all(test, feature = "evrf"))]
-mod evrf;
-
-/// Constant amount of participants to use when testing.
-pub const PARTICIPANTS: u16 = 5;
-/// Constant threshold of participants to use when testing.
-pub const THRESHOLD: u16 = ((PARTICIPANTS * 2) / 3) + 1;
-
-/// Clone a map without a specific value.
-pub fn clone_without<K: Clone + core::cmp::Eq + core::hash::Hash, V: Clone>(
-  map: &HashMap<K, V>,
-  without: &K,
-) -> HashMap<K, V> {
-  let mut res = map.clone();
-  res.remove(without).unwrap();
-  res
-}
-
-/// Recover the secret from a collection of keys.
-///
-/// This will panic if no keys, an insufficient amount of keys, or the wrong keys are provided.
-pub fn recover_key<C: Ciphersuite>(keys: &HashMap<Participant, ThresholdKeys<C>>) -> C::F {
-  let first = keys.values().next().expect("no keys provided");
-  assert!(keys.len() >= first.params().t().into(), "not enough keys provided");
-  let included = keys.keys().copied().collect::<Vec<_>>();
-
-  let group_private = keys.iter().fold(C::F::ZERO, |accum, (i, keys)| {
-    accum +
-      (first.core.interpolation.interpolation_factor(*i, &included) * keys.secret_share().deref())
-  });
-  assert_eq!(C::generator() * group_private, first.group_key(), "failed to recover keys");
-  group_private
-}
-
-/// Generate threshold keys for tests.
-pub fn key_gen<R: RngCore + CryptoRng, C: Ciphersuite>(
-  rng: &mut R,
-) -> HashMap<Participant, ThresholdKeys<C>> {
-  let res = pedpop_gen(rng)
-    .drain()
-    .map(|(i, core)| {
-      assert_eq!(
-        &ThresholdCore::<C>::read::<&[u8]>(&mut core.serialize().as_ref()).unwrap(),
-        &core
-      );
-      (i, ThresholdKeys::new(core))
-    })
-    .collect();
-  assert_eq!(C::generator() * recover_key(&res), res[&Participant(1)].group_key());
-  res
-}
-
-/// Generate MuSig keys for tests.
-pub fn musig_key_gen<R: RngCore + CryptoRng, C: Ciphersuite>(
-  rng: &mut R,
-) -> HashMap<Participant, ThresholdKeys<C>> {
-  let mut keys = vec![];
-  let mut pub_keys = vec![];
-  for _ in 0 .. PARTICIPANTS {
-    let key = Zeroizing::new(C::F::random(&mut *rng));
-    pub_keys.push(C::generator() * *key);
-    keys.push(key);
-  }
-
-  let mut res = HashMap::new();
-  for key in keys {
-    let these_keys = musig_fn::<C>(b"Test MuSig Key Gen", &key, &pub_keys).unwrap();
-    res.insert(these_keys.params().i(), ThresholdKeys::new(these_keys));
-  }
-
-  assert_eq!(C::generator() * recover_key(&res), res[&Participant(1)].group_key());
-  res
-}
-
-/// Run the test suite on a ciphersuite.
-pub fn test_ciphersuite<R: RngCore + CryptoRng, C: Ciphersuite>(rng: &mut R) {
-  key_gen::<_, C>(rng);
-  test_generator_promotion::<_, C>(rng);
-}
-
-#[test]
-fn test_with_ristretto() {
-  test_ciphersuite::<_, ciphersuite::Ristretto>(&mut rand_core::OsRng);
-}

crypto/dkg/src/tests/musig.rs

@@ -1,61 +0,0 @@
-use std::collections::HashMap;
-
-use zeroize::Zeroizing;
-use rand_core::{RngCore, CryptoRng};
-
-use ciphersuite::{group::ff::Field, Ciphersuite};
-
-use crate::{
-  ThresholdKeys,
-  musig::{musig_key, musig},
-  tests::{PARTICIPANTS, recover_key},
-};
-
-/// Tests MuSig key generation.
-pub fn test_musig<R: RngCore + CryptoRng, C: Ciphersuite>(rng: &mut R) {
-  let mut keys = vec![];
-  let mut pub_keys = vec![];
-  for _ in 0 .. PARTICIPANTS {
-    let key = Zeroizing::new(C::F::random(&mut *rng));
-    pub_keys.push(C::generator() * *key);
-    keys.push(key);
-  }
-
-  const CONTEXT: &[u8] = b"MuSig Test";
-
-  // Empty signing set
-  musig::<C>(CONTEXT, &Zeroizing::new(C::F::ZERO), &[]).unwrap_err();
-  // Signing set we're not part of
-  musig::<C>(CONTEXT, &Zeroizing::new(C::F::ZERO), &[C::generator()]).unwrap_err();
-
-  // Test with n keys
-  {
-    let mut created_keys = HashMap::new();
-    let mut verification_shares = HashMap::new();
-    let group_key = musig_key::<C>(CONTEXT, &pub_keys).unwrap();
-    for (i, key) in keys.iter().enumerate() {
-      let these_keys = musig::<C>(CONTEXT, key, &pub_keys).unwrap();
-      assert_eq!(these_keys.params().t(), PARTICIPANTS);
-      assert_eq!(these_keys.params().n(), PARTICIPANTS);
-      assert_eq!(usize::from(these_keys.params().i().0), i + 1);
-
-      verification_shares
-        .insert(these_keys.params().i(), C::generator() * **these_keys.secret_share());
-
-      assert_eq!(these_keys.group_key(), group_key);
-
-      created_keys.insert(these_keys.params().i(), ThresholdKeys::new(these_keys));
-    }
-
-    for keys in created_keys.values() {
-      assert_eq!(keys.verification_shares(), verification_shares);
-    }
-
-    assert_eq!(C::generator() * recover_key(&created_keys), group_key);
-  }
-}
-
-#[test]
-fn musig_literal() {
-  test_musig::<_, ciphersuite::Ristretto>(&mut rand_core::OsRng)
-}

crypto/dkg/src/tests/pedpop.rs

@@ -1,331 +0,0 @@
-use std::collections::HashMap;
-
-use rand_core::{RngCore, CryptoRng};
-
-use ciphersuite::Ciphersuite;
-
-use crate::{
-  Participant, ThresholdParams, ThresholdCore,
-  pedpop::{Commitments, KeyGenMachine, SecretShare, KeyMachine},
-  encryption::{EncryptionKeyMessage, EncryptedMessage},
-  tests::{THRESHOLD, PARTICIPANTS, clone_without},
-};
-
-type PedPoPEncryptedMessage<C> = EncryptedMessage<C, SecretShare<<C as Ciphersuite>::F>>;
-type PedPoPSecretShares<C> = HashMap<Participant, PedPoPEncryptedMessage<C>>;
-
-const CONTEXT: [u8; 32] = *b"DKG Test Key Generation         ";
-
-// Commit, then return commitment messages, enc keys, and shares
-#[allow(clippy::type_complexity)]
-fn commit_enc_keys_and_shares<R: RngCore + CryptoRng, C: Ciphersuite>(
-  rng: &mut R,
-) -> (
-  HashMap<Participant, KeyMachine<C>>,
-  HashMap<Participant, EncryptionKeyMessage<C, Commitments<C>>>,
-  HashMap<Participant, C::G>,
-  HashMap<Participant, PedPoPSecretShares<C>>,
-) {
-  let mut machines = HashMap::new();
-  let mut commitments = HashMap::new();
-  let mut enc_keys = HashMap::new();
-  for i in (1 ..= PARTICIPANTS).map(Participant) {
-    let params = ThresholdParams::new(THRESHOLD, PARTICIPANTS, i).unwrap();
-    let machine = KeyGenMachine::<C>::new(params, CONTEXT);
-    let (machine, these_commitments) = machine.generate_coefficients(rng);
-    machines.insert(i, machine);
-
-    commitments.insert(
-      i,
-      EncryptionKeyMessage::read::<&[u8]>(&mut these_commitments.serialize().as_ref(), params)
-        .unwrap(),
-    );
-    enc_keys.insert(i, commitments[&i].enc_key());
-  }
-
-  let mut secret_shares = HashMap::new();
-  let machines = machines
-    .drain()
-    .map(|(l, machine)| {
-      let (machine, mut shares) =
-        machine.generate_secret_shares(rng, clone_without(&commitments, &l)).unwrap();
-      let shares = shares
-        .drain()
-        .map(|(l, share)| {
-          (
-            l,
-            EncryptedMessage::read::<&[u8]>(
-              &mut share.serialize().as_ref(),
-              // Only t/n actually matters, so hardcode i to 1 here
-              ThresholdParams { t: THRESHOLD, n: PARTICIPANTS, i: Participant(1) },
-            )
-            .unwrap(),
-          )
-        })
-        .collect::<HashMap<_, _>>();
-      secret_shares.insert(l, shares);
-      (l, machine)
-    })
-    .collect::<HashMap<_, _>>();
-
-  (machines, commitments, enc_keys, secret_shares)
-}
-
-fn generate_secret_shares<C: Ciphersuite>(
-  shares: &HashMap<Participant, PedPoPSecretShares<C>>,
-  recipient: Participant,
-) -> PedPoPSecretShares<C> {
-  let mut our_secret_shares = HashMap::new();
-  for (i, shares) in shares {
-    if recipient == *i {
-      continue;
-    }
-    our_secret_shares.insert(*i, shares[&recipient].clone());
-  }
-  our_secret_shares
-}
-
-/// Fully perform the PedPoP key generation algorithm.
-pub fn pedpop_gen<R: RngCore + CryptoRng, C: Ciphersuite>(
-  rng: &mut R,
-) -> HashMap<Participant, ThresholdCore<C>> {
-  let (mut machines, _, _, secret_shares) = commit_enc_keys_and_shares::<_, C>(rng);
-
-  let mut verification_shares = None;
-  let mut group_key = None;
-  machines
-    .drain()
-    .map(|(i, machine)| {
-      let our_secret_shares = generate_secret_shares(&secret_shares, i);
-      let these_keys = machine.calculate_share(rng, our_secret_shares).unwrap().complete();
-
-      // Verify the verification_shares are agreed upon
-      if verification_shares.is_none() {
-        verification_shares = Some(these_keys.verification_shares());
-      }
-      assert_eq!(verification_shares.as_ref().unwrap(), &these_keys.verification_shares());
-
-      // Verify the group keys are agreed upon
-      if group_key.is_none() {
-        group_key = Some(these_keys.group_key());
-      }
-      assert_eq!(group_key.unwrap(), these_keys.group_key());
-
-      (i, these_keys)
-    })
-    .collect::<HashMap<_, _>>()
-}
-
-#[cfg(test)]
-mod literal {
-  use rand_core::OsRng;
-
-  use ciphersuite::Ristretto;
-
-  use crate::{
-    DkgError,
-    encryption::EncryptionKeyProof,
-    pedpop::{BlameMachine, AdditionalBlameMachine},
-  };
-
-  use super::*;
-
-  const ONE: Participant = Participant(1);
-  const TWO: Participant = Participant(2);
-
-  fn test_blame(
-    commitment_msgs: &HashMap<Participant, EncryptionKeyMessage<Ristretto, Commitments<Ristretto>>>,
-    machines: Vec<BlameMachine<Ristretto>>,
-    msg: &PedPoPEncryptedMessage<Ristretto>,
-    blame: &Option<EncryptionKeyProof<Ristretto>>,
-  ) {
-    for machine in machines {
-      let (additional, blamed) = machine.blame(ONE, TWO, msg.clone(), blame.clone());
-      assert_eq!(blamed, ONE);
-      // Verify additional blame also works
-      assert_eq!(additional.blame(ONE, TWO, msg.clone(), blame.clone()), ONE);
-
-      // Verify machines constructed with AdditionalBlameMachine::new work
-      assert_eq!(
-        AdditionalBlameMachine::new(CONTEXT, PARTICIPANTS, commitment_msgs.clone()).unwrap().blame(
-          ONE,
-          TWO,
-          msg.clone(),
-          blame.clone()
-        ),
-        ONE,
-      );
-    }
-  }
-
-  // TODO: Write a macro which expands to the following
-  #[test]
-  fn invalid_encryption_pop_blame() {
-    let (mut machines, commitment_msgs, _, mut secret_shares) =
-      commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
-
-    // Mutate the PoP of the encrypted message from 1 to 2
-    secret_shares.get_mut(&ONE).unwrap().get_mut(&TWO).unwrap().invalidate_pop();
-
-    let mut blame = None;
-    let machines = machines
-      .drain()
-      .filter_map(|(i, machine)| {
-        let our_secret_shares = generate_secret_shares(&secret_shares, i);
-        let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
-        if i == TWO {
-          assert_eq!(machine.err(), Some(DkgError::InvalidShare { participant: ONE, blame: None }));
-          // Explicitly declare we have a blame object, which happens to be None since invalid PoP
-          // is self-explainable
-          blame = Some(None);
-          None
-        } else {
-          Some(machine.unwrap())
-        }
-      })
-      .collect::<Vec<_>>();
-
-    test_blame(&commitment_msgs, machines, &secret_shares[&ONE][&TWO].clone(), &blame.unwrap());
-  }
-
-  #[test]
-  fn invalid_ecdh_blame() {
-    let (mut machines, commitment_msgs, _, mut secret_shares) =
-      commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
-
-    // Mutate the share to trigger a blame event
-    // Mutates from 2 to 1, as 1 is expected to end up malicious for test_blame to pass
-    // While here, 2 is malicious, this is so 1 creates the blame proof
-    // We then malleate 1's blame proof, so 1 ends up malicious
-    // Doesn't simply invalidate the PoP as that won't have a blame statement
-    // By mutating the encrypted data, we do ensure a blame statement is created
-    secret_shares
-      .get_mut(&TWO)
-      .unwrap()
-      .get_mut(&ONE)
-      .unwrap()
-      .invalidate_msg(&mut OsRng, CONTEXT, TWO);
-
-    let mut blame = None;
-    let machines = machines
-      .drain()
-      .filter_map(|(i, machine)| {
-        let our_secret_shares = generate_secret_shares(&secret_shares, i);
-        let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
-        if i == ONE {
-          blame = Some(match machine.err() {
-            Some(DkgError::InvalidShare { participant: TWO, blame: Some(blame) }) => Some(blame),
-            _ => panic!(),
-          });
-          None
-        } else {
-          Some(machine.unwrap())
-        }
-      })
-      .collect::<Vec<_>>();
-
-    blame.as_mut().unwrap().as_mut().unwrap().invalidate_key();
-    test_blame(&commitment_msgs, machines, &secret_shares[&TWO][&ONE].clone(), &blame.unwrap());
-  }
-
-  // This should be largely equivalent to the prior test
-  #[test]
-  fn invalid_dleq_blame() {
-    let (mut machines, commitment_msgs, _, mut secret_shares) =
-      commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
-
-    secret_shares
-      .get_mut(&TWO)
-      .unwrap()
-      .get_mut(&ONE)
-      .unwrap()
-      .invalidate_msg(&mut OsRng, CONTEXT, TWO);
-
-    let mut blame = None;
-    let machines = machines
-      .drain()
-      .filter_map(|(i, machine)| {
-        let our_secret_shares = generate_secret_shares(&secret_shares, i);
-        let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
-        if i == ONE {
-          blame = Some(match machine.err() {
-            Some(DkgError::InvalidShare { participant: TWO, blame: Some(blame) }) => Some(blame),
-            _ => panic!(),
-          });
-          None
-        } else {
-          Some(machine.unwrap())
-        }
-      })
-      .collect::<Vec<_>>();
-
-    blame.as_mut().unwrap().as_mut().unwrap().invalidate_dleq();
-    test_blame(&commitment_msgs, machines, &secret_shares[&TWO][&ONE].clone(), &blame.unwrap());
-  }
-
-  #[test]
-  fn invalid_share_serialization_blame() {
-    let (mut machines, commitment_msgs, enc_keys, mut secret_shares) =
-      commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
-
-    secret_shares.get_mut(&ONE).unwrap().get_mut(&TWO).unwrap().invalidate_share_serialization(
-      &mut OsRng,
-      CONTEXT,
-      ONE,
-      enc_keys[&TWO],
-    );
-
-    let mut blame = None;
-    let machines = machines
-      .drain()
-      .filter_map(|(i, machine)| {
-        let our_secret_shares = generate_secret_shares(&secret_shares, i);
-        let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
-        if i == TWO {
-          blame = Some(match machine.err() {
-            Some(DkgError::InvalidShare { participant: ONE, blame: Some(blame) }) => Some(blame),
-            _ => panic!(),
-          });
-          None
-        } else {
-          Some(machine.unwrap())
-        }
-      })
-      .collect::<Vec<_>>();
-
-    test_blame(&commitment_msgs, machines, &secret_shares[&ONE][&TWO].clone(), &blame.unwrap());
-  }
-
-  #[test]
-  fn invalid_share_value_blame() {
-    let (mut machines, commitment_msgs, enc_keys, mut secret_shares) =
-      commit_enc_keys_and_shares::<_, Ristretto>(&mut OsRng);
-
-    secret_shares.get_mut(&ONE).unwrap().get_mut(&TWO).unwrap().invalidate_share_value(
-      &mut OsRng,
-      CONTEXT,
-      ONE,
-      enc_keys[&TWO],
-    );
-
-    let mut blame = None;
-    let machines = machines
-      .drain()
-      .filter_map(|(i, machine)| {
-        let our_secret_shares = generate_secret_shares(&secret_shares, i);
-        let machine = machine.calculate_share(&mut OsRng, our_secret_shares);
-        if i == TWO {
-          blame = Some(match machine.err() {
-            Some(DkgError::InvalidShare { participant: ONE, blame: Some(blame) }) => Some(blame),
-            _ => panic!(),
-          });
-          None
-        } else {
-          Some(machine.unwrap())
-        }
-      })
-      .collect::<Vec<_>>();
-
-    test_blame(&commitment_msgs, machines, &secret_shares[&ONE][&TWO].clone(), &blame.unwrap());
-  }
-}

crypto/dkg/src/tests/promote.rs

@@ -1,66 +0,0 @@
-use core::{marker::PhantomData, ops::Deref};
-use std::collections::HashMap;
-
-use rand_core::{RngCore, CryptoRng};
-
-use zeroize::Zeroize;
-
-use ciphersuite::{group::Group, Ciphersuite};
-
-use crate::{
-  promote::{GeneratorPromotion, GeneratorProof},
-  tests::{clone_without, key_gen, recover_key},
-};
-
-#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
-struct AltGenerator<C: Ciphersuite> {
-  _curve: PhantomData<C>,
-}
-
-impl<C: Ciphersuite> Ciphersuite for AltGenerator<C> {
-  type F = C::F;
-  type G = C::G;
-  type H = C::H;
-
-  const ID: &'static [u8] = b"Alternate Ciphersuite";
-
-  fn generator() -> Self::G {
-    C::G::generator() * <C as Ciphersuite>::hash_to_F(b"DKG Promotion Test", b"generator")
-  }
-
-  fn reduce_512(scalar: [u8; 64]) -> Self::F {
-    <C as Ciphersuite>::reduce_512(scalar)
-  }
-
-  fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
-    <C as Ciphersuite>::hash_to_F(dst, data)
-  }
-}
-
-// Test promotion of threshold keys to another generator
-pub(crate) fn test_generator_promotion<R: RngCore + CryptoRng, C: Ciphersuite>(rng: &mut R) {
-  let keys = key_gen::<_, C>(&mut *rng);
-
-  let mut promotions = HashMap::new();
-  let mut proofs = HashMap::new();
-  for (i, keys) in &keys {
-    let (promotion, proof) =
-      GeneratorPromotion::<_, AltGenerator<C>>::promote(&mut *rng, keys.clone());
-    promotions.insert(*i, promotion);
-    proofs.insert(*i, GeneratorProof::<C>::read::<&[u8]>(&mut proof.serialize().as_ref()).unwrap());
-  }
-
-  let new_group_key = AltGenerator::<C>::generator() * recover_key(&keys);
-  for (i, promoting) in promotions.drain() {
-    let promoted = promoting.complete(&clone_without(&proofs, &i)).unwrap();
-    assert_eq!(keys[&i].params(), promoted.params());
-    assert_eq!(keys[&i].secret_share(), promoted.secret_share());
-    assert_eq!(new_group_key, promoted.group_key());
-    for (l, verification_share) in promoted.verification_shares() {
-      assert_eq!(
-        AltGenerator::<C>::generator() * keys[&l].secret_share().deref(),
-        verification_share
-      );
-    }
-  }
-}

crypto/ed448/Cargo.toml

@@ -1,13 +1,13 @@
 [package]
 name = "minimal-ed448"
-version = "0.4.0"
+version = "0.4.2"
 description = "Unaudited, inefficient implementation of Ed448 in Rust"
 license = "MIT"
 repository = "https://github.com/serai-dex/serai/tree/develop/crypto/ed448"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["ed448", "ff", "group"]
 edition = "2021"
-rust-version = "1.71"
+rust-version = "1.65"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -24,8 +24,11 @@ rand_core = { version = "0.6", default-features = false }
 zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive"] }
 subtle = { version = "^2.4", default-features = false }
 
+sha3 = { version = "0.10", default-features = false }
+
 ff = { version = "0.13", default-features = false, features = ["bits"] }
 group = { version = "0.13", default-features = false }
+ciphersuite = { path = "../ciphersuite", default-features = false }
 
 generic-array = { version = "1", default-features = false }
 crypto-bigint = { version = "0.5", default-features = false, features = ["zeroize"] }
@@ -38,5 +41,6 @@ rand_core = { version = "0.6", default-features = false, features = ["std"] }
 ff-group-tests = { path = "../ff-group-tests" }
 
 [features]
-std = ["rand_core/std", "zeroize/std", "subtle/std", "ff/std"]
+alloc = ["zeroize/alloc", "ciphersuite/alloc"]
+std = ["alloc", "rand_core/std", "zeroize/std", "subtle/std", "sha3/std", "ff/std", "ciphersuite/std"]
 default = ["std"]

crypto/ed448/src/backend.rs

@@ -2,11 +2,19 @@ use zeroize::Zeroize;
 
 // Use black_box when possible
 #[rustversion::since(1.66)]
-use core::hint::black_box;
-#[rustversion::before(1.66)]
-fn black_box<T>(val: T) -> T {
-  val
+mod black_box {
+  pub(crate) fn black_box<T>(val: T) -> T {
+    #[allow(clippy::incompatible_msrv)]
+    core::hint::black_box(val)
+  }
 }
+#[rustversion::before(1.66)]
+mod black_box {
+  pub(crate) fn black_box<T>(val: T) -> T {
+    val
+  }
+}
+use black_box::black_box;
 
 pub(crate) fn u8_from_bool(bit_ref: &mut bool) -> u8 {
   let bit_ref = black_box(bit_ref);

crypto/ed448/src/ciphersuite.rs

@@ -1,15 +1,17 @@
 use zeroize::Zeroize;
 
-use digest::{
+use sha3::{
+  digest::{
     typenum::U114, core_api::BlockSizeUser, Update, Output, OutputSizeUser, FixedOutput,
     ExtendableOutput, XofReader, HashMarker, Digest,
+  },
+  Shake256,
 };
-use sha3::Shake256;
 
 use group::Group;
-use minimal_ed448::{Scalar, Point};
+use crate::{Scalar, Point};
 
-use crate::Ciphersuite;
+use ciphersuite::Ciphersuite;
 
 /// Shake256, fixed to a 114-byte output, as used by Ed448.
 #[derive(Clone, Default)]
@@ -66,12 +68,6 @@ impl Ciphersuite for Ed448 {
     Point::generator()
   }
 
-  fn reduce_512(mut scalar: [u8; 64]) -> Self::F {
-    let res = Self::hash_to_F(b"Ciphersuite-reduce_512", &scalar);
-    scalar.zeroize();
-    res
-  }
-
   fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
     Scalar::wide_reduce(Self::H::digest([dst, data].concat()).as_ref().try_into().unwrap())
   }

crypto/ed448/src/lib.rs

@@ -14,3 +14,6 @@ pub use field::FieldElement;
 
 mod point;
 pub use point::Point;
+
+mod ciphersuite;
+pub use crate::ciphersuite::Ed448;

crypto/ed448/src/point.rs

@@ -50,13 +50,25 @@ fn recover_x(y: FieldElement) -> CtOption<FieldElement> {
 }
 
 /// Ed448 point.
-#[derive(Clone, Copy, Debug, Zeroize)]
+#[derive(Clone, Copy, Debug)]
 pub struct Point {
   x: FieldElement,
   y: FieldElement,
   z: FieldElement,
 }
 
+impl Zeroize for Point {
+  fn zeroize(&mut self) {
+    self.x.zeroize();
+    self.y.zeroize();
+    self.z.zeroize();
+    let identity = Self::identity();
+    self.x = identity.x;
+    self.y = identity.y;
+    self.z = identity.z;
+  }
+}
+
 const G: Point = Point { x: G_X, y: G_Y, z: FieldElement::ONE };
 
 impl ConstantTimeEq for Point {

crypto/evrf/circuit-abstraction/Cargo.toml

@@ -1,27 +0,0 @@
-[package]
-name = "generalized-bulletproofs-circuit-abstraction"
-version = "0.1.0"
-description = "An abstraction for arithmetic circuits over Generalized Bulletproofs"
-license = "MIT"
-repository = "https://github.com/serai-dex/serai/tree/develop/crypto/fcmps/circuit-abstraction"
-authors = ["Luke Parker <lukeparker5132@gmail.com>"]
-keywords = ["bulletproofs", "circuit"]
-edition = "2021"
-rust-version = "1.69"
-
-[package.metadata.docs.rs]
-all-features = true
-rustdoc-args = ["--cfg", "docsrs"]
-
-[dependencies]
-std-shims = { path = "../../../common/std-shims", version = "^0.1.1", default-features = false }
-
-zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive"] }
-
-ciphersuite = { path = "../../ciphersuite", version = "0.4", default-features = false }
-
-generalized-bulletproofs = { path = "../generalized-bulletproofs", default-features = false }
-
-[features]
-std = ["std-shims/std", "zeroize/std", "ciphersuite/std", "generalized-bulletproofs/std"]
-default = ["std"]

crypto/evrf/circuit-abstraction/README.md

@@ -1,3 +0,0 @@
-# Generalized Bulletproofs Circuit Abstraction
-
-A circuit abstraction around `generalized-bulletproofs`.

crypto/evrf/circuit-abstraction/src/gadgets.rs

@@ -1,39 +0,0 @@
-use ciphersuite::{group::ff::Field, Ciphersuite};
-
-use crate::*;
-
-impl<C: Ciphersuite> Circuit<C> {
-  /// Constrain two linear combinations to be equal.
-  pub fn equality(&mut self, a: LinComb<C::F>, b: &LinComb<C::F>) {
-    self.constrain_equal_to_zero(a - b);
-  }
-
-  /// Calculate (and constrain) the inverse of a value.
-  ///
-  /// A linear combination may optionally be passed as a constraint for the value being inverted.
-  /// A reference to the inverted value and its inverse is returned.
-  ///
-  /// May panic if any linear combinations reference non-existent terms, the witness isn't provided
-  /// when proving/is provided when verifying, or if the witness is 0 (and accordingly doesn't have
-  /// an inverse).
-  pub fn inverse(
-    &mut self,
-    lincomb: Option<LinComb<C::F>>,
-    witness: Option<C::F>,
-  ) -> (Variable, Variable) {
-    let (l, r, o) = self.mul(lincomb, None, witness.map(|f| (f, f.invert().unwrap())));
-    // The output of a value multiplied by its inverse is 1
-    // Constrain `1 o - 1 = 0`
-    self.constrain_equal_to_zero(LinComb::from(o).constant(-C::F::ONE));
-    (l, r)
-  }
-
-  /// Constrain two linear combinations as inequal.
-  ///
-  /// May panic if any linear combinations reference non-existent terms.
-  pub fn inequality(&mut self, a: LinComb<C::F>, b: &LinComb<C::F>, witness: Option<(C::F, C::F)>) {
-    let l_constraint = a - b;
-    // The existence of a multiplicative inverse means a-b != 0, which means a != b
-    self.inverse(Some(l_constraint), witness.map(|(a, b)| a - b));
-  }
-}

crypto/evrf/circuit-abstraction/src/lib.rs

@@ -1,197 +0,0 @@
-#![cfg_attr(docsrs, feature(doc_auto_cfg))]
-#![doc = include_str!("../README.md")]
-#![cfg_attr(not(feature = "std"), no_std)]
-#![deny(missing_docs)]
-#![allow(non_snake_case)]
-
-use std_shims::{vec, vec::Vec};
-
-use zeroize::{Zeroize, ZeroizeOnDrop};
-
-use ciphersuite::{group::ff::Field, Ciphersuite};
-
-use generalized_bulletproofs::{
-  ScalarVector, PedersenCommitment, PedersenVectorCommitment, ProofGenerators,
-  transcript::{Transcript as ProverTranscript, VerifierTranscript, Commitments},
-  arithmetic_circuit_proof::{AcError, ArithmeticCircuitStatement, ArithmeticCircuitWitness},
-};
-pub use generalized_bulletproofs::arithmetic_circuit_proof::{Variable, LinComb};
-
-mod gadgets;
-
-/// A trait for the transcript, whether proving for verifying, as necessary for sampling
-/// challenges.
-pub trait Transcript {
-  /// Sample a challenge from the transacript.
-  ///
-  /// It is the caller's responsibility to have properly transcripted all variables prior to
-  /// sampling this challenge.
-  fn challenge<C: Ciphersuite>(&mut self) -> C::F;
-
-  /// Sample a challenge as a byte array.
-  ///
-  /// It is the caller's responsibility to have properly transcripted all variables prior to
-  /// sampling this challenge.
-  fn challenge_bytes(&mut self) -> [u8; 64];
-}
-impl Transcript for ProverTranscript {
-  fn challenge<C: Ciphersuite>(&mut self) -> C::F {
-    self.challenge::<C>()
-  }
-  fn challenge_bytes(&mut self) -> [u8; 64] {
-    self.challenge_bytes()
-  }
-}
-impl Transcript for VerifierTranscript<'_> {
-  fn challenge<C: Ciphersuite>(&mut self) -> C::F {
-    self.challenge::<C>()
-  }
-  fn challenge_bytes(&mut self) -> [u8; 64] {
-    self.challenge_bytes()
-  }
-}
-
-/// The witness for the satisfaction of this circuit.
-#[derive(Clone, PartialEq, Eq, Debug, Zeroize, ZeroizeOnDrop)]
-struct ProverData<C: Ciphersuite> {
-  aL: Vec<C::F>,
-  aR: Vec<C::F>,
-  C: Vec<PedersenVectorCommitment<C>>,
-  V: Vec<PedersenCommitment<C>>,
-}
-
-/// A struct representing a circuit.
-#[derive(Clone, PartialEq, Eq, Debug)]
-pub struct Circuit<C: Ciphersuite> {
-  muls: usize,
-  // A series of linear combinations which must evaluate to 0.
-  constraints: Vec<LinComb<C::F>>,
-  prover: Option<ProverData<C>>,
-}
-
-impl<C: Ciphersuite> Circuit<C> {
-  /// Returns the amount of multiplications used by this circuit.
-  pub fn muls(&self) -> usize {
-    self.muls
-  }
-
-  /// Create an instance to prove satisfaction of a circuit with.
-  #[allow(clippy::type_complexity)]
-  pub fn prove(
-    vector_commitments: Vec<PedersenVectorCommitment<C>>,
-    commitments: Vec<PedersenCommitment<C>>,
-  ) -> Self {
-    Self {
-      muls: 0,
-      constraints: vec![],
-      prover: Some(ProverData { aL: vec![], aR: vec![], C: vector_commitments, V: commitments }),
-    }
-  }
-
-  /// Create an instance to verify a proof with.
-  pub fn verify() -> Self {
-    Self { muls: 0, constraints: vec![], prover: None }
-  }
-
-  /// Evaluate a linear combination.
-  ///
-  /// Yields WL aL + WR aR + WO aO + WCG CG + WV V + c.
-  ///
-  /// May panic if the linear combination references non-existent terms.
-  ///
-  /// Returns None if not a prover.
-  pub fn eval(&self, lincomb: &LinComb<C::F>) -> Option<C::F> {
-    self.prover.as_ref().map(|prover| {
-      let mut res = lincomb.c();
-      for (index, weight) in lincomb.WL() {
-        res += prover.aL[*index] * weight;
-      }
-      for (index, weight) in lincomb.WR() {
-        res += prover.aR[*index] * weight;
-      }
-      for (index, weight) in lincomb.WO() {
-        res += prover.aL[*index] * prover.aR[*index] * weight;
-      }
-      for (WCG, C) in lincomb.WCG().iter().zip(&prover.C) {
-        for (j, weight) in WCG {
-          res += C.g_values[*j] * weight;
-        }
-      }
-      for (index, weight) in lincomb.WV() {
-        res += prover.V[*index].value * weight;
-      }
-      res
-    })
-  }
-
-  /// Multiply two values, optionally constrained, returning the constrainable left/right/out
-  /// terms.
-  ///
-  /// May panic if any linear combinations reference non-existent terms or if the witness isn't
-  /// provided when proving/is provided when verifying.
-  pub fn mul(
-    &mut self,
-    a: Option<LinComb<C::F>>,
-    b: Option<LinComb<C::F>>,
-    witness: Option<(C::F, C::F)>,
-  ) -> (Variable, Variable, Variable) {
-    let l = Variable::aL(self.muls);
-    let r = Variable::aR(self.muls);
-    let o = Variable::aO(self.muls);
-    self.muls += 1;
-
-    debug_assert_eq!(self.prover.is_some(), witness.is_some());
-    if let Some(witness) = witness {
-      let prover = self.prover.as_mut().unwrap();
-      prover.aL.push(witness.0);
-      prover.aR.push(witness.1);
-    }
-
-    if let Some(a) = a {
-      self.constrain_equal_to_zero(a.term(-C::F::ONE, l));
-    }
-    if let Some(b) = b {
-      self.constrain_equal_to_zero(b.term(-C::F::ONE, r));
-    }
-
-    (l, r, o)
-  }
-
-  /// Constrain a linear combination to be equal to 0.
-  ///
-  /// May panic if the linear combination references non-existent terms.
-  pub fn constrain_equal_to_zero(&mut self, lincomb: LinComb<C::F>) {
-    self.constraints.push(lincomb);
-  }
-
-  /// Obtain the statement for this circuit.
-  ///
-  /// If configured as the prover, the witness to use is also returned.
-  #[allow(clippy::type_complexity)]
-  pub fn statement(
-    self,
-    generators: ProofGenerators<'_, C>,
-    commitments: Commitments<C>,
-  ) -> Result<(ArithmeticCircuitStatement<'_, C>, Option<ArithmeticCircuitWitness<C>>), AcError> {
-    let statement = ArithmeticCircuitStatement::new(generators, self.constraints, commitments)?;
-
-    let witness = self
-      .prover
-      .map(|mut prover| {
-        // We can't deconstruct the witness as it implements Drop (per ZeroizeOnDrop)
-        // Accordingly, we take the values within it and move forward with those
-        let mut aL = vec![];
-        core::mem::swap(&mut prover.aL, &mut aL);
-        let mut aR = vec![];
-        core::mem::swap(&mut prover.aR, &mut aR);
-        let mut C = vec![];
-        core::mem::swap(&mut prover.C, &mut C);
-        let mut V = vec![];
-        core::mem::swap(&mut prover.V, &mut V);
-        ArithmeticCircuitWitness::new(ScalarVector::from(aL), ScalarVector::from(aR), C, V)
-      })
-      .transpose()?;
-
-    Ok((statement, witness))
-  }
-}

crypto/evrf/divisors/Cargo.toml

@@ -1,41 +0,0 @@
-[package]
-name = "ec-divisors"
-version = "0.1.0"
-description = "A library for calculating elliptic curve divisors"
-license = "MIT"
-repository = "https://github.com/serai-dex/serai/tree/develop/crypto/divisors"
-authors = ["Luke Parker <lukeparker5132@gmail.com>"]
-keywords = ["ciphersuite", "ff", "group"]
-edition = "2021"
-rust-version = "1.69"
-
-[package.metadata.docs.rs]
-all-features = true
-rustdoc-args = ["--cfg", "docsrs"]
-
-[dependencies]
-std-shims = { path = "../../../common/std-shims", version = "^0.1.1", default-features = false }
-
-rand_core = { version = "0.6", default-features = false }
-zeroize = { version = "^1.5", default-features = false, features = ["zeroize_derive"] }
-
-subtle = { version = "2", default-features = false }
-ff = { version = "0.13", default-features = false, features = ["bits"] }
-group = { version = "0.13", default-features = false }
-
-hex = { version = "0.4", default-features = false, optional = true }
-dalek-ff-group = { path = "../../dalek-ff-group", default-features = false, optional = true }
-pasta_curves = { version = "0.5", git = "https://github.com/kayabaNerve/pasta_curves.git", rev = "a46b5be95cacbff54d06aad8d3bbcba42e05d616", default-features = false, features = ["bits", "alloc"], optional = true }
-
-[dev-dependencies]
-rand_core = { version = "0.6", features = ["getrandom"] }
-
-hex = "0.4"
-dalek-ff-group = { path = "../../dalek-ff-group", features = ["std"] }
-pasta_curves = { version = "0.5", git = "https://github.com/kayabaNerve/pasta_curves.git", rev = "a46b5be95cacbff54d06aad8d3bbcba42e05d616", default-features = false, features = ["bits", "alloc"] }
-
-[features]
-std = ["std-shims/std", "zeroize/std", "subtle/std", "ff/std", "dalek-ff-group?/std"]
-ed25519 = ["hex/alloc", "dalek-ff-group"]
-pasta = ["pasta_curves"]
-default = ["std"]

crypto/evrf/divisors/README.md

@@ -1,4 +0,0 @@
-# Elliptic Curve Divisors
-
-An implementation of a representation for and construction of elliptic curve
-divisors, intended for Eagen's [EC IP work](https://eprint.iacr.org/2022/596).

crypto/evrf/divisors/src/lib.rs

@@ -1,581 +0,0 @@
-#![cfg_attr(docsrs, feature(doc_auto_cfg))]
-#![doc = include_str!("../README.md")]
-#![cfg_attr(not(feature = "std"), no_std)]
-#![deny(missing_docs)]
-#![allow(non_snake_case)]
-
-use std_shims::{vec, vec::Vec};
-
-use subtle::{Choice, ConstantTimeEq, ConstantTimeGreater, ConditionallySelectable};
-use zeroize::{Zeroize, ZeroizeOnDrop};
-
-use group::{
-  ff::{Field, PrimeField, PrimeFieldBits},
-  Group,
-};
-
-mod poly;
-pub use poly::Poly;
-
-#[cfg(test)]
-mod tests;
-
-/// A curve usable with this library.
-pub trait DivisorCurve: Group + ConstantTimeEq + ConditionallySelectable + Zeroize {
-  /// An element of the field this curve is defined over.
-  type FieldElement: Zeroize + PrimeField + ConditionallySelectable;
-
-  /// The A in the curve equation y^2 = x^3 + A x + B.
-  fn a() -> Self::FieldElement;
-  /// The B in the curve equation y^2 = x^3 + A x + B.
-  fn b() -> Self::FieldElement;
-
-  /// y^2 - x^3 - A x - B
-  ///
-  /// Section 2 of the security proofs define this modulus.
-  ///
-  /// This MUST NOT be overriden.
-  // TODO: Move to an extension trait
-  fn divisor_modulus() -> Poly<Self::FieldElement> {
-    Poly {
-      // 0 y**1, 1 y*2
-      y_coefficients: vec![Self::FieldElement::ZERO, Self::FieldElement::ONE],
-      yx_coefficients: vec![],
-      x_coefficients: vec![
-        // - A x
-        -Self::a(),
-        // 0 x^2
-        Self::FieldElement::ZERO,
-        // - x^3
-        -Self::FieldElement::ONE,
-      ],
-      // - B
-      zero_coefficient: -Self::b(),
-    }
-  }
-
-  /// Convert a point to its x and y coordinates.
-  ///
-  /// Returns None if passed the point at infinity.
-  ///
-  /// This function may run in time variable to if the point is the identity.
-  fn to_xy(point: Self) -> Option<(Self::FieldElement, Self::FieldElement)>;
-}
-
-/// Calculate the slope and intercept between two points.
-///
-/// This function panics when `a @ infinity`, `b @ infinity`, `a == b`, or when `a == -b`.
-pub(crate) fn slope_intercept<C: DivisorCurve>(a: C, b: C) -> (C::FieldElement, C::FieldElement) {
-  let (ax, ay) = C::to_xy(a).unwrap();
-  debug_assert_eq!(C::divisor_modulus().eval(ax, ay), C::FieldElement::ZERO);
-  let (bx, by) = C::to_xy(b).unwrap();
-  debug_assert_eq!(C::divisor_modulus().eval(bx, by), C::FieldElement::ZERO);
-  let slope = (by - ay) *
-    Option::<C::FieldElement>::from((bx - ax).invert())
-      .expect("trying to get slope/intercept of points sharing an x coordinate");
-  let intercept = by - (slope * bx);
-  debug_assert!(bool::from((ay - (slope * ax) - intercept).is_zero()));
-  debug_assert!(bool::from((by - (slope * bx) - intercept).is_zero()));
-  (slope, intercept)
-}
-
-// The line interpolating two points.
-fn line<C: DivisorCurve>(a: C, b: C) -> Poly<C::FieldElement> {
-  #[derive(Clone, Copy)]
-  struct LinesRes<F: ConditionallySelectable> {
-    y_coefficient: F,
-    x_coefficient: F,
-    zero_coefficient: F,
-  }
-  impl<F: ConditionallySelectable> ConditionallySelectable for LinesRes<F> {
-    fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self {
-      Self {
-        y_coefficient: <_>::conditional_select(&a.y_coefficient, &b.y_coefficient, choice),
-        x_coefficient: <_>::conditional_select(&a.x_coefficient, &b.x_coefficient, choice),
-        zero_coefficient: <_>::conditional_select(&a.zero_coefficient, &b.zero_coefficient, choice),
-      }
-    }
-  }
-
-  let a_is_identity = a.is_identity();
-  let b_is_identity = b.is_identity();
-
-  // If they're both the point at infinity, we simply set the line to one
-  let both_are_identity = a_is_identity & b_is_identity;
-  let if_both_are_identity = LinesRes {
-    y_coefficient: C::FieldElement::ZERO,
-    x_coefficient: C::FieldElement::ZERO,
-    zero_coefficient: C::FieldElement::ONE,
-  };
-
-  // If either point is the point at infinity, or these are additive inverses, the line is
-  // `1 * x - x`. The first `x` is a term in the polynomial, the `x` is the `x` coordinate of these
-  // points (of which there is one, as the second point is either at infinity or has a matching `x`
-  // coordinate).
-  let one_is_identity = a_is_identity | b_is_identity;
-  let additive_inverses = a.ct_eq(&-b);
-  let one_is_identity_or_additive_inverses = one_is_identity | additive_inverses;
-  let if_one_is_identity_or_additive_inverses = {
-    // If both are identity, set `a` to the generator so we can safely evaluate the following
-    // (which we won't select at the end of this function)
-    let a = <_>::conditional_select(&a, &C::generator(), both_are_identity);
-    // If `a` is identity, this selects `b`. If `a` isn't identity, this selects `a`
-    let non_identity = <_>::conditional_select(&a, &b, a.is_identity());
-    let (x, _) = C::to_xy(non_identity).unwrap();
-    LinesRes {
-      y_coefficient: C::FieldElement::ZERO,
-      x_coefficient: C::FieldElement::ONE,
-      zero_coefficient: -x,
-    }
-  };
-
-  // The following calculation assumes neither point is the point at infinity
-  // If either are, we use a prior result
-  // To ensure we can calculcate a result here, set any points at infinity to the generator
-  let a = <_>::conditional_select(&a, &C::generator(), a_is_identity);
-  let b = <_>::conditional_select(&b, &C::generator(), b_is_identity);
-  // It also assumes a, b aren't additive inverses which is also covered by a prior result
-  let b = <_>::conditional_select(&b, &a.double(), additive_inverses);
-
-  // If the points are equal, we use the line interpolating the sum of these points with the point
-  // at infinity
-  let b = <_>::conditional_select(&b, &-a.double(), a.ct_eq(&b));
-
-  let (slope, intercept) = slope_intercept::<C>(a, b);
-
-  // Section 4 of the proofs explicitly state the line `L = y - lambda * x - mu`
-  // y - (slope * x) - intercept
-  let mut res = LinesRes {
-    y_coefficient: C::FieldElement::ONE,
-    x_coefficient: -slope,
-    zero_coefficient: -intercept,
-  };
-
-  res = <_>::conditional_select(
-    &res,
-    &if_one_is_identity_or_additive_inverses,
-    one_is_identity_or_additive_inverses,
-  );
-  res = <_>::conditional_select(&res, &if_both_are_identity, both_are_identity);
-
-  Poly {
-    y_coefficients: vec![res.y_coefficient],
-    yx_coefficients: vec![],
-    x_coefficients: vec![res.x_coefficient],
-    zero_coefficient: res.zero_coefficient,
-  }
-}
-
-/// Create a divisor interpolating the following points.
-///
-/// Returns None if:
-///   - No points were passed in
-///   - The points don't sum to the point at infinity
-///   - A passed in point was the point at infinity
-///
-/// If the arguments were valid, this function executes in an amount of time constant to the amount
-/// of points.
-#[allow(clippy::new_ret_no_self)]
-pub fn new_divisor<C: DivisorCurve>(points: &[C]) -> Option<Poly<C::FieldElement>> {
-  // No points were passed in, this is the point at infinity, or the single point isn't infinity
-  // and accordingly doesn't sum to infinity. All three cause us to return None
-  // Checks a bit other than the first bit is set, meaning this is >= 2
-  let mut invalid_args = (points.len() & (!1)).ct_eq(&0);
-  // The points don't sum to the point at infinity
-  invalid_args |= !points.iter().sum::<C>().is_identity();
-  // A point was the point at identity
-  for point in points {
-    invalid_args |= point.is_identity();
-  }
-  if bool::from(invalid_args) {
-    None?;
-  }
-
-  let points_len = points.len();
-
-  // Create the initial set of divisors
-  let mut divs = vec![];
-  let mut iter = points.iter().copied();
-  while let Some(a) = iter.next() {
-    let b = iter.next();
-
-    // Draw the line between those points
-    // These unwraps are branching on the length of the iterator, not violating the constant-time
-    // priorites desired
-    divs.push((2, a + b.unwrap_or(C::identity()), line::<C>(a, b.unwrap_or(-a))));
-  }
-
-  let modulus = C::divisor_modulus();
-
-  // Our Poly algorithm is leaky and will create an excessive amount of y x**j and x**j
-  // coefficients which are zero, yet as our implementation is constant time, still come with
-  // an immense performance cost. This code truncates the coefficients we know are zero.
-  let trim = |divisor: &mut Poly<_>, points_len: usize| {
-    // We should only be trimming divisors reduced by the modulus
-    debug_assert!(divisor.yx_coefficients.len() <= 1);
-    if divisor.yx_coefficients.len() == 1 {
-      let truncate_to = ((points_len + 1) / 2).saturating_sub(2);
-      #[cfg(debug_assertions)]
-      for p in truncate_to .. divisor.yx_coefficients[0].len() {
-        debug_assert_eq!(divisor.yx_coefficients[0][p], <C::FieldElement as Field>::ZERO);
-      }
-      divisor.yx_coefficients[0].truncate(truncate_to);
-    }
-    {
-      let truncate_to = points_len / 2;
-      #[cfg(debug_assertions)]
-      for p in truncate_to .. divisor.x_coefficients.len() {
-        debug_assert_eq!(divisor.x_coefficients[p], <C::FieldElement as Field>::ZERO);
-      }
-      divisor.x_coefficients.truncate(truncate_to);
-    }
-  };
-
-  // Pair them off until only one remains
-  while divs.len() > 1 {
-    let mut next_divs = vec![];
-    // If there's an odd amount of divisors, carry the odd one out to the next iteration
-    if (divs.len() % 2) == 1 {
-      next_divs.push(divs.pop().unwrap());
-    }
-
-    while let Some((a_points, a, a_div)) = divs.pop() {
-      let (b_points, b, b_div) = divs.pop().unwrap();
-      let points = a_points + b_points;
-
-      // Merge the two divisors
-      let numerator = a_div.mul_mod(&b_div, &modulus).mul_mod(&line::<C>(a, b), &modulus);
-      let denominator = line::<C>(a, -a).mul_mod(&line::<C>(b, -b), &modulus);
-      let (mut q, r) = numerator.div_rem(&denominator);
-      debug_assert_eq!(r, Poly::zero());
-
-      trim(&mut q, 1 + points);
-
-      next_divs.push((points, a + b, q));
-    }
-
-    divs = next_divs;
-  }
-
-  // Return the unified divisor
-  let mut divisor = divs.remove(0).2;
-  trim(&mut divisor, points_len);
-  Some(divisor)
-}
-
-/// The decomposition of a scalar.
-///
-/// The decomposition ($d$) of a scalar ($s$) has the following two properties:
-///
-/// - $\sum^{\mathsf{NUM_BITS} - 1}_{i=0} d_i * 2^i = s$
-/// - $\sum^{\mathsf{NUM_BITS} - 1}_{i=0} d_i = \mathsf{NUM_BITS}$
-#[derive(Clone, Zeroize, ZeroizeOnDrop)]
-pub struct ScalarDecomposition<F: Zeroize + PrimeFieldBits> {
-  scalar: F,
-  decomposition: Vec<u64>,
-}
-
-impl<F: Zeroize + PrimeFieldBits> ScalarDecomposition<F> {
-  /// Decompose a non-zero scalar.
-  ///
-  /// Returns `None` if the scalar is zero.
-  ///
-  /// This function is constant time if the scalar is non-zero.
-  pub fn new(scalar: F) -> Option<Self> {
-    if bool::from(scalar.is_zero()) {
-      None?;
-    }
-
-    /*
-      We need the sum of the coefficients to equal F::NUM_BITS. The scalar's bits will be less than
-      F::NUM_BITS. Accordingly, we need to increment the sum of the coefficients without
-      incrementing the scalar represented. We do this by finding the highest non-0 coefficient,
-      decrementing it, and increasing the immediately less significant coefficient by 2. This
-      increases the sum of the coefficients by 1 (-1+2=1).
-    */
-
-    let num_bits = u64::from(F::NUM_BITS);
-
-    // Obtain the bits of the scalar
-    let num_bits_usize = usize::try_from(num_bits).unwrap();
-    let mut decomposition = vec![0; num_bits_usize];
-    for (i, bit) in scalar.to_le_bits().into_iter().take(num_bits_usize).enumerate() {
-      let bit = u64::from(u8::from(bit));
-      decomposition[i] = bit;
-    }
-
-    // The following algorithm only works if the value of the scalar exceeds num_bits
-    // If it isn't, we increase it by the modulus such that it does exceed num_bits
-    {
-      let mut less_than_num_bits = Choice::from(0);
-      for i in 0 .. num_bits {
-        less_than_num_bits |= scalar.ct_eq(&F::from(i));
-      }
-      let mut decomposition_of_modulus = vec![0; num_bits_usize];
-      // Decompose negative one
-      for (i, bit) in (-F::ONE).to_le_bits().into_iter().take(num_bits_usize).enumerate() {
-        let bit = u64::from(u8::from(bit));
-        decomposition_of_modulus[i] = bit;
-      }
-      // Increment it by one
-      decomposition_of_modulus[0] += 1;
-
-      // Add the decomposition onto the decomposition of the modulus
-      for i in 0 .. num_bits_usize {
-        let new_decomposition = <_>::conditional_select(
-          &decomposition[i],
-          &(decomposition[i] + decomposition_of_modulus[i]),
-          less_than_num_bits,
-        );
-        decomposition[i] = new_decomposition;
-      }
-    }
-
-    // Calculcate the sum of the coefficients
-    let mut sum_of_coefficients: u64 = 0;
-    for decomposition in &decomposition {
-      sum_of_coefficients += *decomposition;
-    }
-
-    /*
-      Now, because we added a log2(k)-bit number to a k-bit number, we may have our sum of
-      coefficients be *too high*. We attempt to reduce the sum of the coefficients accordingly.
-
-      This algorithm is guaranteed to complete as expected. Take the sequence `222`. `222` becomes
-      `032` becomes `013`. Even if the next coefficient in the sequence is `2`, the third
-      coefficient will be reduced once and the next coefficient (`2`, increased to `3`) will only
-      be eligible for reduction once. This demonstrates, even for a worst case of log2(k) `2`s
-      followed by `1`s (as possible if the modulus is a Mersenne prime), the log2(k) `2`s can be
-      reduced as necessary so long as there is a single coefficient after (requiring the entire
-      sequence be at least of length log2(k) + 1). For a 2-bit number, log2(k) + 1 == 2, so this
-      holds for any odd prime field.
-
-      To fully type out the demonstration for the Mersenne prime 3, with scalar to encode 1 (the
-      highest value less than the number of bits):
-
-      10 - Little-endian bits of 1
-      21 - Little-endian bits of 1, plus the modulus
-      02 - After one reduction, where the sum of the coefficients does in fact equal 2 (the target)
-    */
-    {
-      let mut log2_num_bits = 0;
-      while (1 << log2_num_bits) < num_bits {
-        log2_num_bits += 1;
-      }
-
-      for _ in 0 .. log2_num_bits {
-        // If the sum of coefficients is the amount of bits, we're done
-        let mut done = sum_of_coefficients.ct_eq(&num_bits);
-
-        for i in 0 .. (num_bits_usize - 1) {
-          let should_act = (!done) & decomposition[i].ct_gt(&1);
-          // Subtract 2 from this coefficient
-          let amount_to_sub = <_>::conditional_select(&0, &2, should_act);
-          decomposition[i] -= amount_to_sub;
-          // Add 1 to the next coefficient
-          let amount_to_add = <_>::conditional_select(&0, &1, should_act);
-          decomposition[i + 1] += amount_to_add;
-
-          // Also update the sum of coefficients
-          sum_of_coefficients -= <_>::conditional_select(&0, &1, should_act);
-
-          // If we updated the coefficients this loop iter, we're done for this loop iter
-          done |= should_act;
-        }
-      }
-    }
-
-    for _ in 0 .. num_bits {
-      // If the sum of coefficients is the amount of bits, we're done
-      let mut done = sum_of_coefficients.ct_eq(&num_bits);
-
-      // Find the highest coefficient currently non-zero
-      for i in (1 .. decomposition.len()).rev() {
-        // If this is non-zero, we should decrement this coefficient if we haven't already
-        // decremented a coefficient this round
-        let is_non_zero = !(0.ct_eq(&decomposition[i]));
-        let should_act = (!done) & is_non_zero;
-
-        // Update this coefficient and the prior coefficient
-        let amount_to_sub = <_>::conditional_select(&0, &1, should_act);
-        decomposition[i] -= amount_to_sub;
-
-        let amount_to_add = <_>::conditional_select(&0, &2, should_act);
-        // i must be at least 1, so i - 1 will be at least 0 (meaning it's safe to index with)
-        decomposition[i - 1] += amount_to_add;
-
-        // Also update the sum of coefficients
-        sum_of_coefficients += <_>::conditional_select(&0, &1, should_act);
-
-        // If we updated the coefficients this loop iter, we're done for this loop iter
-        done |= should_act;
-      }
-    }
-    debug_assert!(bool::from(decomposition.iter().sum::<u64>().ct_eq(&num_bits)));
-
-    Some(ScalarDecomposition { scalar, decomposition })
-  }
-
-  /// The scalar.
-  pub fn scalar(&self) -> &F {
-    &self.scalar
-  }
-
-  /// The decomposition of the scalar.
-  pub fn decomposition(&self) -> &[u64] {
-    &self.decomposition
-  }
-
-  /// A divisor to prove a scalar multiplication.
-  ///
-  /// The divisor will interpolate $-(s \cdot G)$ with $d_i$ instances of $2^i \cdot G$.
-  ///
-  /// This function executes in constant time with regards to the scalar.
-  ///
-  /// This function MAY panic if the generator is the point at infinity.
-  pub fn scalar_mul_divisor<C: Zeroize + DivisorCurve<Scalar = F>>(
-    &self,
-    mut generator: C,
-  ) -> Poly<C::FieldElement> {
-    // 1 is used for the resulting point, NUM_BITS is used for the decomposition, and then we store
-    // one additional index in a usize for the points we shouldn't write at all (hence the +2)
-    let _ = usize::try_from(<C::Scalar as PrimeField>::NUM_BITS + 2)
-      .expect("NUM_BITS + 2 didn't fit in usize");
-    let mut divisor_points =
-      vec![C::identity(); (<C::Scalar as PrimeField>::NUM_BITS + 1) as usize];
-
-    // Write the inverse of the resulting point
-    divisor_points[0] = -generator * self.scalar;
-
-    // Write the decomposition
-    let mut write_above: u64 = 0;
-    for coefficient in &self.decomposition {
-      // Write the generator to every slot except the slots we have already written to.
-      for i in 1 ..= (<C::Scalar as PrimeField>::NUM_BITS as u64) {
-        divisor_points[i as usize].conditional_assign(&generator, i.ct_gt(&write_above));
-      }
-
-      // Increase the next write start by the coefficient.
-      write_above += coefficient;
-      generator = generator.double();
-    }
-
-    // Create a divisor out of the points
-    let res = new_divisor(&divisor_points).unwrap();
-    divisor_points.zeroize();
-    res
-  }
-}
-
-#[cfg(any(test, feature = "pasta"))]
-mod pasta {
-  use group::{ff::Field, Curve};
-  use pasta_curves::{
-    arithmetic::{Coordinates, CurveAffine},
-    Ep, Fp, Eq, Fq,
-  };
-  use crate::DivisorCurve;
-
-  impl DivisorCurve for Ep {
-    type FieldElement = Fp;
-
-    fn a() -> Self::FieldElement {
-      Self::FieldElement::ZERO
-    }
-    fn b() -> Self::FieldElement {
-      Self::FieldElement::from(5u64)
-    }
-
-    fn to_xy(point: Self) -> Option<(Self::FieldElement, Self::FieldElement)> {
-      Option::<Coordinates<_>>::from(point.to_affine().coordinates())
-        .map(|coords| (*coords.x(), *coords.y()))
-    }
-  }
-
-  impl DivisorCurve for Eq {
-    type FieldElement = Fq;
-
-    fn a() -> Self::FieldElement {
-      Self::FieldElement::ZERO
-    }
-    fn b() -> Self::FieldElement {
-      Self::FieldElement::from(5u64)
-    }
-
-    fn to_xy(point: Self) -> Option<(Self::FieldElement, Self::FieldElement)> {
-      Option::<Coordinates<_>>::from(point.to_affine().coordinates())
-        .map(|coords| (*coords.x(), *coords.y()))
-    }
-  }
-}
-
-#[cfg(any(test, feature = "ed25519"))]
-mod ed25519 {
-  use subtle::{Choice, ConditionallySelectable};
-  use group::{
-    ff::{Field, PrimeField},
-    Group, GroupEncoding,
-  };
-  use dalek_ff_group::{FieldElement, EdwardsPoint};
-
-  impl crate::DivisorCurve for EdwardsPoint {
-    type FieldElement = FieldElement;
-
-    // Wei25519 a/b
-    // https://www.ietf.org/archive/id/draft-ietf-lwig-curve-representations-02.pdf E.3
-    fn a() -> Self::FieldElement {
-      let mut be_bytes =
-        hex::decode("2aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa984914a144").unwrap();
-      be_bytes.reverse();
-      let le_bytes = be_bytes;
-      Self::FieldElement::from_repr(le_bytes.try_into().unwrap()).unwrap()
-    }
-    fn b() -> Self::FieldElement {
-      let mut be_bytes =
-        hex::decode("7b425ed097b425ed097b425ed097b425ed097b425ed097b4260b5e9c7710c864").unwrap();
-      be_bytes.reverse();
-      let le_bytes = be_bytes;
-
-      Self::FieldElement::from_repr(le_bytes.try_into().unwrap()).unwrap()
-    }
-
-    // https://www.ietf.org/archive/id/draft-ietf-lwig-curve-representations-02.pdf E.2
-    fn to_xy(point: Self) -> Option<(Self::FieldElement, Self::FieldElement)> {
-      if bool::from(point.is_identity()) {
-        None?;
-      }
-
-      // Extract the y coordinate from the compressed point
-      let mut edwards_y = point.to_bytes();
-      let x_is_odd = edwards_y[31] >> 7;
-      edwards_y[31] &= (1 << 7) - 1;
-      let edwards_y = Self::FieldElement::from_repr(edwards_y).unwrap();
-
-      // Recover the x coordinate
-      let edwards_y_sq = edwards_y * edwards_y;
-      let D = -Self::FieldElement::from(121665u64) *
-        Self::FieldElement::from(121666u64).invert().unwrap();
-      let mut edwards_x = ((edwards_y_sq - Self::FieldElement::ONE) *
-        ((D * edwards_y_sq) + Self::FieldElement::ONE).invert().unwrap())
-      .sqrt()
-      .unwrap();
-
-      // Negate the x coordinate if the sign doesn't match
-      edwards_x = <_>::conditional_select(
-        &edwards_x,
-        &-edwards_x,
-        edwards_x.is_odd() ^ Choice::from(x_is_odd),
-      );
-
-      // Calculate the x and y coordinates for Wei25519
-      let edwards_y_plus_one = Self::FieldElement::ONE + edwards_y;
-      let one_minus_edwards_y = Self::FieldElement::ONE - edwards_y;
-      let wei_x = (edwards_y_plus_one * one_minus_edwards_y.invert().unwrap()) +
-        (Self::FieldElement::from(486662u64) * Self::FieldElement::from(3u64).invert().unwrap());
-      let c =
-        (-(Self::FieldElement::from(486662u64) + Self::FieldElement::from(2u64))).sqrt().unwrap();
-      let wei_y = c * edwards_y_plus_one * (one_minus_edwards_y * edwards_x).invert().unwrap();
-      Some((wei_x, wei_y))
-    }
-  }
-}

crypto/evrf/divisors/src/poly.rs

@@ -1,744 +0,0 @@
-use core::ops::{Add, Neg, Sub, Mul, Rem};
-use std_shims::{vec, vec::Vec};
-
-use subtle::{Choice, ConstantTimeEq, ConstantTimeGreater, ConditionallySelectable};
-use zeroize::{Zeroize, ZeroizeOnDrop};
-
-use group::ff::PrimeField;
-
-#[derive(Clone, Copy, PartialEq, Debug)]
-struct CoefficientIndex {
-  y_pow: u64,
-  x_pow: u64,
-}
-impl ConditionallySelectable for CoefficientIndex {
-  fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self {
-    Self {
-      y_pow: <_>::conditional_select(&a.y_pow, &b.y_pow, choice),
-      x_pow: <_>::conditional_select(&a.x_pow, &b.x_pow, choice),
-    }
-  }
-}
-impl ConstantTimeEq for CoefficientIndex {
-  fn ct_eq(&self, other: &Self) -> Choice {
-    self.y_pow.ct_eq(&other.y_pow) & self.x_pow.ct_eq(&other.x_pow)
-  }
-}
-impl ConstantTimeGreater for CoefficientIndex {
-  fn ct_gt(&self, other: &Self) -> Choice {
-    self.y_pow.ct_gt(&other.y_pow) |
-      (self.y_pow.ct_eq(&other.y_pow) & self.x_pow.ct_gt(&other.x_pow))
-  }
-}
-
-/// A structure representing a Polynomial with x^i, y^i, and y^i * x^j terms.
-#[derive(Clone, Debug, Zeroize, ZeroizeOnDrop)]
-pub struct Poly<F: From<u64> + Zeroize + PrimeField> {
-  /// c\[i] * y^(i + 1)
-  pub y_coefficients: Vec<F>,
-  /// c\[i]\[j] * y^(i + 1) x^(j + 1)
-  pub yx_coefficients: Vec<Vec<F>>,
-  /// c\[i] * x^(i + 1)
-  pub x_coefficients: Vec<F>,
-  /// Coefficient for x^0, y^0, and x^0 y^0 (the coefficient for 1)
-  pub zero_coefficient: F,
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> PartialEq for Poly<F> {
-  // This is not constant time and is not meant to be
-  fn eq(&self, b: &Poly<F>) -> bool {
-    {
-      let mutual_y_coefficients = self.y_coefficients.len().min(b.y_coefficients.len());
-      if self.y_coefficients[.. mutual_y_coefficients] != b.y_coefficients[.. mutual_y_coefficients]
-      {
-        return false;
-      }
-      for coeff in &self.y_coefficients[mutual_y_coefficients ..] {
-        if *coeff != F::ZERO {
-          return false;
-        }
-      }
-      for coeff in &b.y_coefficients[mutual_y_coefficients ..] {
-        if *coeff != F::ZERO {
-          return false;
-        }
-      }
-    }
-
-    {
-      for (i, yx_coeffs) in self.yx_coefficients.iter().enumerate() {
-        for (j, coeff) in yx_coeffs.iter().enumerate() {
-          if coeff != b.yx_coefficients.get(i).unwrap_or(&vec![]).get(j).unwrap_or(&F::ZERO) {
-            return false;
-          }
-        }
-      }
-      // Run from the other perspective in case other is longer than self
-      for (i, yx_coeffs) in b.yx_coefficients.iter().enumerate() {
-        for (j, coeff) in yx_coeffs.iter().enumerate() {
-          if coeff != self.yx_coefficients.get(i).unwrap_or(&vec![]).get(j).unwrap_or(&F::ZERO) {
-            return false;
-          }
-        }
-      }
-    }
-
-    {
-      let mutual_x_coefficients = self.x_coefficients.len().min(b.x_coefficients.len());
-      if self.x_coefficients[.. mutual_x_coefficients] != b.x_coefficients[.. mutual_x_coefficients]
-      {
-        return false;
-      }
-      for coeff in &self.x_coefficients[mutual_x_coefficients ..] {
-        if *coeff != F::ZERO {
-          return false;
-        }
-      }
-      for coeff in &b.x_coefficients[mutual_x_coefficients ..] {
-        if *coeff != F::ZERO {
-          return false;
-        }
-      }
-    }
-
-    self.zero_coefficient == b.zero_coefficient
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Poly<F> {
-  /// A polynomial for zero.
-  pub(crate) fn zero() -> Self {
-    Poly {
-      y_coefficients: vec![],
-      yx_coefficients: vec![],
-      x_coefficients: vec![],
-      zero_coefficient: F::ZERO,
-    }
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Add<&Self> for Poly<F> {
-  type Output = Self;
-
-  fn add(mut self, other: &Self) -> Self {
-    // Expand to be the neeeded size
-    while self.y_coefficients.len() < other.y_coefficients.len() {
-      self.y_coefficients.push(F::ZERO);
-    }
-    while self.yx_coefficients.len() < other.yx_coefficients.len() {
-      self.yx_coefficients.push(vec![]);
-    }
-    for i in 0 .. other.yx_coefficients.len() {
-      while self.yx_coefficients[i].len() < other.yx_coefficients[i].len() {
-        self.yx_coefficients[i].push(F::ZERO);
-      }
-    }
-    while self.x_coefficients.len() < other.x_coefficients.len() {
-      self.x_coefficients.push(F::ZERO);
-    }
-
-    // Perform the addition
-    for (i, coeff) in other.y_coefficients.iter().enumerate() {
-      self.y_coefficients[i] += coeff;
-    }
-    for (i, coeffs) in other.yx_coefficients.iter().enumerate() {
-      for (j, coeff) in coeffs.iter().enumerate() {
-        self.yx_coefficients[i][j] += coeff;
-      }
-    }
-    for (i, coeff) in other.x_coefficients.iter().enumerate() {
-      self.x_coefficients[i] += coeff;
-    }
-    self.zero_coefficient += other.zero_coefficient;
-
-    self
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Neg for Poly<F> {
-  type Output = Self;
-
-  fn neg(mut self) -> Self {
-    for y_coeff in self.y_coefficients.iter_mut() {
-      *y_coeff = -*y_coeff;
-    }
-    for yx_coeffs in self.yx_coefficients.iter_mut() {
-      for yx_coeff in yx_coeffs.iter_mut() {
-        *yx_coeff = -*yx_coeff;
-      }
-    }
-    for x_coeff in self.x_coefficients.iter_mut() {
-      *x_coeff = -*x_coeff;
-    }
-    self.zero_coefficient = -self.zero_coefficient;
-
-    self
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Sub for Poly<F> {
-  type Output = Self;
-
-  fn sub(self, other: Self) -> Self {
-    self + &-other
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Mul<F> for Poly<F> {
-  type Output = Self;
-
-  fn mul(mut self, scalar: F) -> Self {
-    for y_coeff in self.y_coefficients.iter_mut() {
-      *y_coeff *= scalar;
-    }
-    for coeffs in self.yx_coefficients.iter_mut() {
-      for coeff in coeffs.iter_mut() {
-        *coeff *= scalar;
-      }
-    }
-    for x_coeff in self.x_coefficients.iter_mut() {
-      *x_coeff *= scalar;
-    }
-    self.zero_coefficient *= scalar;
-    self
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Poly<F> {
-  #[must_use]
-  fn shift_by_x(mut self, power_of_x: usize) -> Self {
-    if power_of_x == 0 {
-      return self;
-    }
-
-    // Shift up every x coefficient
-    for _ in 0 .. power_of_x {
-      self.x_coefficients.insert(0, F::ZERO);
-      for yx_coeffs in &mut self.yx_coefficients {
-        yx_coeffs.insert(0, F::ZERO);
-      }
-    }
-
-    // Move the zero coefficient
-    self.x_coefficients[power_of_x - 1] = self.zero_coefficient;
-    self.zero_coefficient = F::ZERO;
-
-    // Move the y coefficients
-    // Start by creating yx coefficients with the necessary powers of x
-    let mut yx_coefficients_to_push = vec![];
-    while yx_coefficients_to_push.len() < power_of_x {
-      yx_coefficients_to_push.push(F::ZERO);
-    }
-    // Now, ensure the yx coefficients has the slots for the y coefficients we're moving
-    while self.yx_coefficients.len() < self.y_coefficients.len() {
-      self.yx_coefficients.push(yx_coefficients_to_push.clone());
-    }
-    // Perform the move
-    for (i, y_coeff) in self.y_coefficients.drain(..).enumerate() {
-      self.yx_coefficients[i][power_of_x - 1] = y_coeff;
-    }
-
-    self
-  }
-
-  #[must_use]
-  fn shift_by_y(mut self, power_of_y: usize) -> Self {
-    if power_of_y == 0 {
-      return self;
-    }
-
-    // Shift up every y coefficient
-    for _ in 0 .. power_of_y {
-      self.y_coefficients.insert(0, F::ZERO);
-      self.yx_coefficients.insert(0, vec![]);
-    }
-
-    // Move the zero coefficient
-    self.y_coefficients[power_of_y - 1] = self.zero_coefficient;
-    self.zero_coefficient = F::ZERO;
-
-    // Move the x coefficients
-    core::mem::swap(&mut self.yx_coefficients[power_of_y - 1], &mut self.x_coefficients);
-    self.x_coefficients = vec![];
-
-    self
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Mul<&Poly<F>> for Poly<F> {
-  type Output = Self;
-
-  fn mul(self, other: &Self) -> Self {
-    let mut res = self.clone() * other.zero_coefficient;
-
-    for (i, y_coeff) in other.y_coefficients.iter().enumerate() {
-      let scaled = self.clone() * *y_coeff;
-      res = res + &scaled.shift_by_y(i + 1);
-    }
-
-    for (y_i, yx_coeffs) in other.yx_coefficients.iter().enumerate() {
-      for (x_i, yx_coeff) in yx_coeffs.iter().enumerate() {
-        let scaled = self.clone() * *yx_coeff;
-        res = res + &scaled.shift_by_y(y_i + 1).shift_by_x(x_i + 1);
-      }
-    }
-
-    for (i, x_coeff) in other.x_coefficients.iter().enumerate() {
-      let scaled = self.clone() * *x_coeff;
-      res = res + &scaled.shift_by_x(i + 1);
-    }
-
-    res
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Poly<F> {
-  // The leading y coefficient and associated x coefficient.
-  fn leading_coefficient(&self) -> (usize, usize) {
-    if self.y_coefficients.len() > self.yx_coefficients.len() {
-      (self.y_coefficients.len(), 0)
-    } else if !self.yx_coefficients.is_empty() {
-      (self.yx_coefficients.len(), self.yx_coefficients.last().unwrap().len())
-    } else {
-      (0, self.x_coefficients.len())
-    }
-  }
-
-  /// Returns the highest non-zero coefficient greater than the specified coefficient.
-  ///
-  /// If no non-zero coefficient is greater than the specified coefficient, this will return
-  /// (0, 0).
-  fn greater_than_or_equal_coefficient(
-    &self,
-    greater_than_or_equal: &CoefficientIndex,
-  ) -> CoefficientIndex {
-    let mut leading_coefficient = CoefficientIndex { y_pow: 0, x_pow: 0 };
-    for (y_pow_sub_one, coeff) in self.y_coefficients.iter().enumerate() {
-      let y_pow = u64::try_from(y_pow_sub_one + 1).unwrap();
-      let coeff_is_non_zero = !coeff.is_zero();
-      let potential = CoefficientIndex { y_pow, x_pow: 0 };
-      leading_coefficient = <_>::conditional_select(
-        &leading_coefficient,
-        &potential,
-        coeff_is_non_zero &
-          potential.ct_gt(&leading_coefficient) &
-          (potential.ct_gt(greater_than_or_equal) | potential.ct_eq(greater_than_or_equal)),
-      );
-    }
-    for (y_pow_sub_one, yx_coefficients) in self.yx_coefficients.iter().enumerate() {
-      let y_pow = u64::try_from(y_pow_sub_one + 1).unwrap();
-      for (x_pow_sub_one, coeff) in yx_coefficients.iter().enumerate() {
-        let x_pow = u64::try_from(x_pow_sub_one + 1).unwrap();
-        let coeff_is_non_zero = !coeff.is_zero();
-        let potential = CoefficientIndex { y_pow, x_pow };
-        leading_coefficient = <_>::conditional_select(
-          &leading_coefficient,
-          &potential,
-          coeff_is_non_zero &
-            potential.ct_gt(&leading_coefficient) &
-            (potential.ct_gt(greater_than_or_equal) | potential.ct_eq(greater_than_or_equal)),
-        );
-      }
-    }
-    for (x_pow_sub_one, coeff) in self.x_coefficients.iter().enumerate() {
-      let x_pow = u64::try_from(x_pow_sub_one + 1).unwrap();
-      let coeff_is_non_zero = !coeff.is_zero();
-      let potential = CoefficientIndex { y_pow: 0, x_pow };
-      leading_coefficient = <_>::conditional_select(
-        &leading_coefficient,
-        &potential,
-        coeff_is_non_zero &
-          potential.ct_gt(&leading_coefficient) &
-          (potential.ct_gt(greater_than_or_equal) | potential.ct_eq(greater_than_or_equal)),
-      );
-    }
-    leading_coefficient
-  }
-
-  /// Perform multiplication mod `modulus`.
-  #[must_use]
-  pub(crate) fn mul_mod(self, other: &Self, modulus: &Self) -> Self {
-    (self * other) % modulus
-  }
-
-  /// Perform division, returning the result and remainder.
-  ///
-  /// This function is constant time to the structure of the numerator and denominator. The actual
-  /// value of the coefficients will not introduce timing differences.
-  ///
-  /// Panics upon division by a polynomial where all coefficients are zero.
-  #[must_use]
-  pub(crate) fn div_rem(self, denominator: &Self) -> (Self, Self) {
-    // These functions have undefined behavior if this isn't a valid index for this poly
-    fn ct_get<F: From<u64> + Zeroize + PrimeField>(poly: &Poly<F>, index: CoefficientIndex) -> F {
-      let mut res = poly.zero_coefficient;
-      for (y_pow_sub_one, coeff) in poly.y_coefficients.iter().enumerate() {
-        res = <_>::conditional_select(
-          &res,
-          coeff,
-          index
-            .ct_eq(&CoefficientIndex { y_pow: (y_pow_sub_one + 1).try_into().unwrap(), x_pow: 0 }),
-        );
-      }
-      for (y_pow_sub_one, coeffs) in poly.yx_coefficients.iter().enumerate() {
-        for (x_pow_sub_one, coeff) in coeffs.iter().enumerate() {
-          res = <_>::conditional_select(
-            &res,
-            coeff,
-            index.ct_eq(&CoefficientIndex {
-              y_pow: (y_pow_sub_one + 1).try_into().unwrap(),
-              x_pow: (x_pow_sub_one + 1).try_into().unwrap(),
-            }),
-          );
-        }
-      }
-      for (x_pow_sub_one, coeff) in poly.x_coefficients.iter().enumerate() {
-        res = <_>::conditional_select(
-          &res,
-          coeff,
-          index
-            .ct_eq(&CoefficientIndex { y_pow: 0, x_pow: (x_pow_sub_one + 1).try_into().unwrap() }),
-        );
-      }
-      res
-    }
-
-    fn ct_set<F: From<u64> + Zeroize + PrimeField>(
-      poly: &mut Poly<F>,
-      index: CoefficientIndex,
-      value: F,
-    ) {
-      for (y_pow_sub_one, coeff) in poly.y_coefficients.iter_mut().enumerate() {
-        *coeff = <_>::conditional_select(
-          coeff,
-          &value,
-          index
-            .ct_eq(&CoefficientIndex { y_pow: (y_pow_sub_one + 1).try_into().unwrap(), x_pow: 0 }),
-        );
-      }
-      for (y_pow_sub_one, coeffs) in poly.yx_coefficients.iter_mut().enumerate() {
-        for (x_pow_sub_one, coeff) in coeffs.iter_mut().enumerate() {
-          *coeff = <_>::conditional_select(
-            coeff,
-            &value,
-            index.ct_eq(&CoefficientIndex {
-              y_pow: (y_pow_sub_one + 1).try_into().unwrap(),
-              x_pow: (x_pow_sub_one + 1).try_into().unwrap(),
-            }),
-          );
-        }
-      }
-      for (x_pow_sub_one, coeff) in poly.x_coefficients.iter_mut().enumerate() {
-        *coeff = <_>::conditional_select(
-          coeff,
-          &value,
-          index
-            .ct_eq(&CoefficientIndex { y_pow: 0, x_pow: (x_pow_sub_one + 1).try_into().unwrap() }),
-        );
-      }
-      poly.zero_coefficient = <_>::conditional_select(
-        &poly.zero_coefficient,
-        &value,
-        index.ct_eq(&CoefficientIndex { y_pow: 0, x_pow: 0 }),
-      );
-    }
-
-    fn conditional_select_poly<F: From<u64> + Zeroize + PrimeField>(
-      mut a: Poly<F>,
-      mut b: Poly<F>,
-      choice: Choice,
-    ) -> Poly<F> {
-      let pad_to = |a: &mut Poly<F>, b: &Poly<F>| {
-        while a.x_coefficients.len() < b.x_coefficients.len() {
-          a.x_coefficients.push(F::ZERO);
-        }
-        while a.yx_coefficients.len() < b.yx_coefficients.len() {
-          a.yx_coefficients.push(vec![]);
-        }
-        for (a, b) in a.yx_coefficients.iter_mut().zip(&b.yx_coefficients) {
-          while a.len() < b.len() {
-            a.push(F::ZERO);
-          }
-        }
-        while a.y_coefficients.len() < b.y_coefficients.len() {
-          a.y_coefficients.push(F::ZERO);
-        }
-      };
-      // Pad these to be the same size/layout as each other
-      pad_to(&mut a, &b);
-      pad_to(&mut b, &a);
-
-      let mut res = Poly::zero();
-      for (a, b) in a.y_coefficients.iter().zip(&b.y_coefficients) {
-        res.y_coefficients.push(<_>::conditional_select(a, b, choice));
-      }
-      for (a, b) in a.yx_coefficients.iter().zip(&b.yx_coefficients) {
-        let mut yx_coefficients = Vec::with_capacity(a.len());
-        for (a, b) in a.iter().zip(b) {
-          yx_coefficients.push(<_>::conditional_select(a, b, choice))
-        }
-        res.yx_coefficients.push(yx_coefficients);
-      }
-      for (a, b) in a.x_coefficients.iter().zip(&b.x_coefficients) {
-        res.x_coefficients.push(<_>::conditional_select(a, b, choice));
-      }
-      res.zero_coefficient =
-        <_>::conditional_select(&a.zero_coefficient, &b.zero_coefficient, choice);
-
-      res
-    }
-
-    // The following long division algorithm only works if the denominator actually has a variable
-    // If the denominator isn't variable to anything, short-circuit to scalar 'division'
-    // This is safe as `leading_coefficient` is based on the structure, not the values, of the poly
-    let denominator_leading_coefficient = denominator.leading_coefficient();
-    if denominator_leading_coefficient == (0, 0) {
-      return (self * denominator.zero_coefficient.invert().unwrap(), Poly::zero());
-    }
-
-    // The structure of the quotient, which is the the numerator with all coefficients set to 0
-    let mut quotient_structure = Poly {
-      y_coefficients: vec![F::ZERO; self.y_coefficients.len()],
-      yx_coefficients: self.yx_coefficients.clone(),
-      x_coefficients: vec![F::ZERO; self.x_coefficients.len()],
-      zero_coefficient: F::ZERO,
-    };
-    for coeff in quotient_structure
-      .yx_coefficients
-      .iter_mut()
-      .flat_map(|yx_coefficients| yx_coefficients.iter_mut())
-    {
-      *coeff = F::ZERO;
-    }
-
-    // Calculate the amount of iterations we need to perform
-    let iterations = self.y_coefficients.len() +
-      self.yx_coefficients.iter().map(|yx_coefficients| yx_coefficients.len()).sum::<usize>() +
-      self.x_coefficients.len();
-
-    // Find the highest non-zero coefficient in the denominator
-    // This is the coefficient which we actually perform division with
-    let denominator_dividing_coefficient =
-      denominator.greater_than_or_equal_coefficient(&CoefficientIndex { y_pow: 0, x_pow: 0 });
-    let denominator_dividing_coefficient_inv =
-      ct_get(denominator, denominator_dividing_coefficient).invert().unwrap();
-
-    let mut quotient = quotient_structure.clone();
-    let mut remainder = self.clone();
-    for _ in 0 .. iterations {
-      // Find the numerator coefficient we're clearing
-      // This will be (0, 0) if we aren't clearing a coefficient
-      let numerator_coefficient =
-        remainder.greater_than_or_equal_coefficient(&denominator_dividing_coefficient);
-
-      // We only apply the effects of this iteration if the numerator's coefficient is actually >=
-      let meaningful_iteration = numerator_coefficient.ct_gt(&denominator_dividing_coefficient) |
-        numerator_coefficient.ct_eq(&denominator_dividing_coefficient);
-
-      // 1) Find the scalar `q` such that the leading coefficient of `q * denominator` is equal to
-      //    the leading coefficient of self.
-      let numerator_coefficient_value = ct_get(&remainder, numerator_coefficient);
-      let q = numerator_coefficient_value * denominator_dividing_coefficient_inv;
-
-      // 2) Calculate the full term of the quotient by scaling with the necessary powers of y/x
-      let proper_powers_of_yx = CoefficientIndex {
-        y_pow: numerator_coefficient.y_pow.wrapping_sub(denominator_dividing_coefficient.y_pow),
-        x_pow: numerator_coefficient.x_pow.wrapping_sub(denominator_dividing_coefficient.x_pow),
-      };
-      let fallabck_powers_of_yx = CoefficientIndex { y_pow: 0, x_pow: 0 };
-      let mut quotient_term = quotient_structure.clone();
-      ct_set(
-        &mut quotient_term,
-        // If the numerator coefficient isn't >=, proper_powers_of_yx will have garbage in them
-        <_>::conditional_select(&fallabck_powers_of_yx, &proper_powers_of_yx, meaningful_iteration),
-        q,
-      );
-
-      let quotient_if_meaningful = quotient.clone() + &quotient_term;
-      quotient = conditional_select_poly(quotient, quotient_if_meaningful, meaningful_iteration);
-
-      // 3) Remove what we've divided out from self
-      let remainder_if_meaningful = remainder.clone() - (quotient_term * denominator);
-      remainder = conditional_select_poly(remainder, remainder_if_meaningful, meaningful_iteration);
-    }
-
-    quotient = conditional_select_poly(
-      quotient,
-      // If the dividing coefficient was for y**0 x**0, we return the poly scaled by its inverse
-      self * denominator_dividing_coefficient_inv,
-      denominator_dividing_coefficient.ct_eq(&CoefficientIndex { y_pow: 0, x_pow: 0 }),
-    );
-    remainder = conditional_select_poly(
-      remainder,
-      // If the dividing coefficient was for y**0 x**0, we're able to perfectly divide and there's
-      // no remainder
-      Poly::zero(),
-      denominator_dividing_coefficient.ct_eq(&CoefficientIndex { y_pow: 0, x_pow: 0 }),
-    );
-
-    // Clear any junk terms out of the remainder which are less than the denominator
-    let denominator_leading_coefficient = CoefficientIndex {
-      y_pow: denominator_leading_coefficient.0.try_into().unwrap(),
-      x_pow: denominator_leading_coefficient.1.try_into().unwrap(),
-    };
-    if denominator_leading_coefficient != (CoefficientIndex { y_pow: 0, x_pow: 0 }) {
-      while {
-        let index =
-          CoefficientIndex { y_pow: remainder.y_coefficients.len().try_into().unwrap(), x_pow: 0 };
-        bool::from(
-          index.ct_gt(&denominator_leading_coefficient) |
-            index.ct_eq(&denominator_leading_coefficient),
-        )
-      } {
-        let popped = remainder.y_coefficients.pop();
-        debug_assert_eq!(popped, Some(F::ZERO));
-      }
-      while {
-        let index = CoefficientIndex {
-          y_pow: remainder.yx_coefficients.len().try_into().unwrap(),
-          x_pow: remainder
-            .yx_coefficients
-            .last()
-            .map(|yx_coefficients| yx_coefficients.len())
-            .unwrap_or(0)
-            .try_into()
-            .unwrap(),
-        };
-        bool::from(
-          index.ct_gt(&denominator_leading_coefficient) |
-            index.ct_eq(&denominator_leading_coefficient),
-        )
-      } {
-        let popped = remainder.yx_coefficients.last_mut().unwrap().pop();
-        // This may have been `vec![]`
-        if let Some(popped) = popped {
-          debug_assert_eq!(popped, F::ZERO);
-        }
-        if remainder.yx_coefficients.last().unwrap().is_empty() {
-          let popped = remainder.yx_coefficients.pop();
-          debug_assert_eq!(popped, Some(vec![]));
-        }
-      }
-      while {
-        let index =
-          CoefficientIndex { y_pow: 0, x_pow: remainder.x_coefficients.len().try_into().unwrap() };
-        bool::from(
-          index.ct_gt(&denominator_leading_coefficient) |
-            index.ct_eq(&denominator_leading_coefficient),
-        )
-      } {
-        let popped = remainder.x_coefficients.pop();
-        debug_assert_eq!(popped, Some(F::ZERO));
-      }
-    }
-
-    (quotient, remainder)
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Rem<&Self> for Poly<F> {
-  type Output = Self;
-
-  fn rem(self, modulus: &Self) -> Self {
-    self.div_rem(modulus).1
-  }
-}
-
-impl<F: From<u64> + Zeroize + PrimeField> Poly<F> {
-  /// Evaluate this polynomial with the specified x/y values.
-  ///
-  /// Panics on polynomials with terms whose powers exceed 2^64.
-  #[must_use]
-  pub fn eval(&self, x: F, y: F) -> F {
-    let mut res = self.zero_coefficient;
-    for (pow, coeff) in
-      self.y_coefficients.iter().enumerate().map(|(i, v)| (u64::try_from(i + 1).unwrap(), v))
-    {
-      res += y.pow([pow]) * coeff;
-    }
-    for (y_pow, coeffs) in
-      self.yx_coefficients.iter().enumerate().map(|(i, v)| (u64::try_from(i + 1).unwrap(), v))
-    {
-      let y_pow = y.pow([y_pow]);
-      for (x_pow, coeff) in
-        coeffs.iter().enumerate().map(|(i, v)| (u64::try_from(i + 1).unwrap(), v))
-      {
-        res += y_pow * x.pow([x_pow]) * coeff;
-      }
-    }
-    for (pow, coeff) in
-      self.x_coefficients.iter().enumerate().map(|(i, v)| (u64::try_from(i + 1).unwrap(), v))
-    {
-      res += x.pow([pow]) * coeff;
-    }
-    res
-  }
-
-  /// Differentiate a polynomial, reduced by a modulus with a leading y term y^2 x^0, by x and y.
-  ///
-  /// This function has undefined behavior if unreduced.
-  #[must_use]
-  pub fn differentiate(&self) -> (Poly<F>, Poly<F>) {
-    // Differentation by x practically involves:
-    // - Dropping everything without an x component
-    // - Shifting everything down a power of x
-    // - Multiplying the new coefficient by the power it prior was used with
-    let diff_x = {
-      let mut diff_x = Poly {
-        y_coefficients: vec![],
-        yx_coefficients: vec![],
-        x_coefficients: vec![],
-        zero_coefficient: F::ZERO,
-      };
-      if !self.x_coefficients.is_empty() {
-        let mut x_coeffs = self.x_coefficients.clone();
-        diff_x.zero_coefficient = x_coeffs.remove(0);
-        diff_x.x_coefficients = x_coeffs;
-
-        let mut prior_x_power = F::from(2);
-        for x_coeff in &mut diff_x.x_coefficients {
-          *x_coeff *= prior_x_power;
-          prior_x_power += F::ONE;
-        }
-      }
-
-      if !self.yx_coefficients.is_empty() {
-        let mut yx_coeffs = self.yx_coefficients[0].clone();
-        if !yx_coeffs.is_empty() {
-          diff_x.y_coefficients = vec![yx_coeffs.remove(0)];
-          diff_x.yx_coefficients = vec![yx_coeffs];
-
-          let mut prior_x_power = F::from(2);
-          for yx_coeff in &mut diff_x.yx_coefficients[0] {
-            *yx_coeff *= prior_x_power;
-            prior_x_power += F::ONE;
-          }
-        }
-      }
-
-      diff_x
-    };
-
-    // Differentation by y is trivial
-    // It's the y coefficient as the zero coefficient, and the yx coefficients as the x
-    // coefficients
-    // This is thanks to any y term over y^2 being reduced out
-    let diff_y = Poly {
-      y_coefficients: vec![],
-      yx_coefficients: vec![],
-      x_coefficients: self.yx_coefficients.first().cloned().unwrap_or(vec![]),
-      zero_coefficient: self.y_coefficients.first().cloned().unwrap_or(F::ZERO),
-    };
-
-    (diff_x, diff_y)
-  }
-
-  /// Normalize the x coefficient to 1.
-  ///
-  /// Panics if there is no x coefficient to normalize or if it cannot be normalized to 1.
-  #[must_use]
-  pub fn normalize_x_coefficient(self) -> Self {
-    let scalar = self.x_coefficients[0].invert().unwrap();
-    self * scalar
-  }
-}

crypto/evrf/divisors/src/tests/mod.rs

@@ -1,237 +0,0 @@
-use rand_core::OsRng;
-
-use group::{ff::Field, Group};
-use dalek_ff_group::EdwardsPoint;
-use pasta_curves::{Ep, Eq};
-
-use crate::{DivisorCurve, Poly, new_divisor};
-
-mod poly;
-
-// Equation 4 in the security proofs
-fn check_divisor<C: DivisorCurve>(points: Vec<C>) {
-  // Create the divisor
-  let divisor = new_divisor::<C>(&points).unwrap();
-  let eval = |c| {
-    let (x, y) = C::to_xy(c).unwrap();
-    divisor.eval(x, y)
-  };
-
-  // Decide challgenges
-  let c0 = C::random(&mut OsRng);
-  let c1 = C::random(&mut OsRng);
-  let c2 = -(c0 + c1);
-  let (slope, intercept) = crate::slope_intercept::<C>(c0, c1);
-
-  let mut rhs = <C as DivisorCurve>::FieldElement::ONE;
-  for point in points {
-    let (x, y) = C::to_xy(point).unwrap();
-    rhs *= intercept - (y - (slope * x));
-  }
-  assert_eq!(eval(c0) * eval(c1) * eval(c2), rhs);
-}
-
-fn test_divisor<C: DivisorCurve>() {
-  for i in 1 ..= 255 {
-    println!("Test iteration {i}");
-
-    // Select points
-    let mut points = vec![];
-    for _ in 0 .. i {
-      points.push(C::random(&mut OsRng));
-    }
-    points.push(-points.iter().sum::<C>());
-    println!("Points {}", points.len());
-
-    // Perform the original check
-    check_divisor(points.clone());
-
-    // Create the divisor
-    let divisor = new_divisor::<C>(&points).unwrap();
-
-    // For a divisor interpolating 256 points, as one does when interpreting a 255-bit discrete log
-    // with the result of its scalar multiplication against a fixed generator, the lengths of the
-    // yx/x coefficients shouldn't supersede the following bounds
-    assert!((divisor.yx_coefficients.first().unwrap_or(&vec![]).len()) <= 126);
-    assert!((divisor.x_coefficients.len() - 1) <= 127);
-    assert!(
-      (1 + divisor.yx_coefficients.first().unwrap_or(&vec![]).len() +
-        (divisor.x_coefficients.len() - 1) +
-        1) <=
-        255
-    );
-
-    // Decide challgenges
-    let c0 = C::random(&mut OsRng);
-    let c1 = C::random(&mut OsRng);
-    let c2 = -(c0 + c1);
-    let (slope, intercept) = crate::slope_intercept::<C>(c0, c1);
-
-    // Perform the Logarithmic derivative check
-    {
-      let dx_over_dz = {
-        let dx = Poly {
-          y_coefficients: vec![],
-          yx_coefficients: vec![],
-          x_coefficients: vec![C::FieldElement::ZERO, C::FieldElement::from(3)],
-          zero_coefficient: C::a(),
-        };
-
-        let dy = Poly {
-          y_coefficients: vec![C::FieldElement::from(2)],
-          yx_coefficients: vec![],
-          x_coefficients: vec![],
-          zero_coefficient: C::FieldElement::ZERO,
-        };
-
-        let dz = (dy.clone() * -slope) + &dx;
-
-        // We want dx/dz, and dz/dx is equal to dy/dx - slope
-        // Sagemath claims this, dy / dz, is the proper inverse
-        (dy, dz)
-      };
-
-      {
-        let sanity_eval = |c| {
-          let (x, y) = C::to_xy(c).unwrap();
-          dx_over_dz.0.eval(x, y) * dx_over_dz.1.eval(x, y).invert().unwrap()
-        };
-        let sanity = sanity_eval(c0) + sanity_eval(c1) + sanity_eval(c2);
-        // This verifies the dx/dz polynomial is correct
-        assert_eq!(sanity, C::FieldElement::ZERO);
-      }
-
-      // Logarithmic derivative check
-      let test = |divisor: Poly<_>| {
-        let (dx, dy) = divisor.differentiate();
-
-        let lhs = |c| {
-          let (x, y) = C::to_xy(c).unwrap();
-
-          let n_0 = (C::FieldElement::from(3) * (x * x)) + C::a();
-          let d_0 = (C::FieldElement::from(2) * y).invert().unwrap();
-          let p_0_n_0 = n_0 * d_0;
-
-          let n_1 = dy.eval(x, y);
-          let first = p_0_n_0 * n_1;
-
-          let second = dx.eval(x, y);
-
-          let d_1 = divisor.eval(x, y);
-
-          let fraction_1_n = first + second;
-          let fraction_1_d = d_1;
-
-          let fraction_2_n = dx_over_dz.0.eval(x, y);
-          let fraction_2_d = dx_over_dz.1.eval(x, y);
-
-          fraction_1_n * fraction_2_n * (fraction_1_d * fraction_2_d).invert().unwrap()
-        };
-        let lhs = lhs(c0) + lhs(c1) + lhs(c2);
-
-        let mut rhs = C::FieldElement::ZERO;
-        for point in &points {
-          let (x, y) = <C as DivisorCurve>::to_xy(*point).unwrap();
-          rhs += (intercept - (y - (slope * x))).invert().unwrap();
-        }
-
-        assert_eq!(lhs, rhs);
-      };
-      // Test the divisor and the divisor with a normalized x coefficient
-      test(divisor.clone());
-      test(divisor.normalize_x_coefficient());
-    }
-  }
-}
-
-fn test_same_point<C: DivisorCurve>() {
-  let mut points = vec![C::random(&mut OsRng)];
-  points.push(points[0]);
-  points.push(-points.iter().sum::<C>());
-  check_divisor(points);
-}
-
-fn test_subset_sum_to_infinity<C: DivisorCurve>() {
-  // Internally, a binary tree algorithm is used
-  // This executes the first pass to end up with [0, 0] for further reductions
-  {
-    let mut points = vec![C::random(&mut OsRng)];
-    points.push(-points[0]);
-
-    let next = C::random(&mut OsRng);
-    points.push(next);
-    points.push(-next);
-    check_divisor(points);
-  }
-
-  // This executes the first pass to end up with [0, X, -X, 0]
-  {
-    let mut points = vec![C::random(&mut OsRng)];
-    points.push(-points[0]);
-
-    let x_1 = C::random(&mut OsRng);
-    let x_2 = C::random(&mut OsRng);
-    points.push(x_1);
-    points.push(x_2);
-
-    points.push(-x_1);
-    points.push(-x_2);
-
-    let next = C::random(&mut OsRng);
-    points.push(next);
-    points.push(-next);
-    check_divisor(points);
-  }
-}
-
-#[test]
-fn test_divisor_pallas() {
-  test_same_point::<Ep>();
-  test_subset_sum_to_infinity::<Ep>();
-  test_divisor::<Ep>();
-}
-
-#[test]
-fn test_divisor_vesta() {
-  test_same_point::<Eq>();
-  test_subset_sum_to_infinity::<Eq>();
-  test_divisor::<Eq>();
-}
-
-#[test]
-fn test_divisor_ed25519() {
-  // Since we're implementing Wei25519 ourselves, check the isomorphism works as expected
-  {
-    let incomplete_add = |p1, p2| {
-      let (x1, y1) = EdwardsPoint::to_xy(p1).unwrap();
-      let (x2, y2) = EdwardsPoint::to_xy(p2).unwrap();
-
-      // mmadd-1998-cmo
-      let u = y2 - y1;
-      let uu = u * u;
-      let v = x2 - x1;
-      let vv = v * v;
-      let vvv = v * vv;
-      let R = vv * x1;
-      let A = uu - vvv - R.double();
-      let x3 = v * A;
-      let y3 = (u * (R - A)) - (vvv * y1);
-      let z3 = vvv;
-
-      // Normalize from XYZ to XY
-      let x3 = x3 * z3.invert().unwrap();
-      let y3 = y3 * z3.invert().unwrap();
-
-      // Edwards addition -> Wei25519 coordinates should be equivalent to Wei25519 addition
-      assert_eq!(EdwardsPoint::to_xy(p1 + p2).unwrap(), (x3, y3));
-    };
-
-    for _ in 0 .. 256 {
-      incomplete_add(EdwardsPoint::random(&mut OsRng), EdwardsPoint::random(&mut OsRng));
-    }
-  }
-
-  test_same_point::<EdwardsPoint>();
-  test_subset_sum_to_infinity::<EdwardsPoint>();
-  test_divisor::<EdwardsPoint>();
-}

crypto/evrf/divisors/src/tests/poly.rs

@@ -1,148 +0,0 @@
-use rand_core::OsRng;
-
-use group::ff::Field;
-use pasta_curves::Ep;
-
-use crate::{DivisorCurve, Poly};
-
-type F = <Ep as DivisorCurve>::FieldElement;
-
-#[test]
-fn test_poly() {
-  let zero = F::ZERO;
-  let one = F::ONE;
-
-  {
-    let mut poly = Poly::zero();
-    poly.y_coefficients = vec![zero, one];
-
-    let mut modulus = Poly::zero();
-    modulus.y_coefficients = vec![one];
-    assert_eq!(
-      poly.clone().div_rem(&modulus).0,
-      Poly {
-        y_coefficients: vec![one],
-        yx_coefficients: vec![],
-        x_coefficients: vec![],
-        zero_coefficient: zero
-      }
-    );
-    assert_eq!(
-      poly % &modulus,
-      Poly {
-        y_coefficients: vec![],
-        yx_coefficients: vec![],
-        x_coefficients: vec![],
-        zero_coefficient: zero
-      }
-    );
-  }
-
-  {
-    let mut poly = Poly::zero();
-    poly.y_coefficients = vec![zero, one];
-
-    let mut squared = Poly::zero();
-    squared.y_coefficients = vec![zero, zero, zero, one];
-    assert_eq!(poly.clone() * &poly, squared);
-  }
-
-  {
-    let mut a = Poly::zero();
-    a.zero_coefficient = F::from(2u64);
-
-    let mut b = Poly::zero();
-    b.zero_coefficient = F::from(3u64);
-
-    let mut res = Poly::zero();
-    res.zero_coefficient = F::from(6u64);
-    assert_eq!(a.clone() * &b, res);
-
-    b.y_coefficients = vec![F::from(4u64)];
-    res.y_coefficients = vec![F::from(8u64)];
-    assert_eq!(a.clone() * &b, res);
-    assert_eq!(b.clone() * &a, res);
-
-    a.x_coefficients = vec![F::from(5u64)];
-    res.x_coefficients = vec![F::from(15u64)];
-    res.yx_coefficients = vec![vec![F::from(20u64)]];
-    assert_eq!(a.clone() * &b, res);
-    assert_eq!(b * &a, res);
-
-    // res is now 20xy + 8*y + 15*x + 6
-    // res ** 2 =
-    //   400*x^2*y^2 + 320*x*y^2 + 64*y^2 + 600*x^2*y + 480*x*y + 96*y + 225*x^2 + 180*x + 36
-
-    let mut squared = Poly::zero();
-    squared.y_coefficients = vec![F::from(96u64), F::from(64u64)];
-    squared.yx_coefficients =
-      vec![vec![F::from(480u64), F::from(600u64)], vec![F::from(320u64), F::from(400u64)]];
-    squared.x_coefficients = vec![F::from(180u64), F::from(225u64)];
-    squared.zero_coefficient = F::from(36u64);
-    assert_eq!(res.clone() * &res, squared);
-  }
-}
-
-#[test]
-fn test_differentation() {
-  let random = || F::random(&mut OsRng);
-
-  let input = Poly {
-    y_coefficients: vec![random()],
-    yx_coefficients: vec![vec![random()]],
-    x_coefficients: vec![random(), random(), random()],
-    zero_coefficient: random(),
-  };
-  let (diff_x, diff_y) = input.differentiate();
-  assert_eq!(
-    diff_x,
-    Poly {
-      y_coefficients: vec![input.yx_coefficients[0][0]],
-      yx_coefficients: vec![],
-      x_coefficients: vec![
-        F::from(2) * input.x_coefficients[1],
-        F::from(3) * input.x_coefficients[2]
-      ],
-      zero_coefficient: input.x_coefficients[0],
-    }
-  );
-  assert_eq!(
-    diff_y,
-    Poly {
-      y_coefficients: vec![],
-      yx_coefficients: vec![],
-      x_coefficients: vec![input.yx_coefficients[0][0]],
-      zero_coefficient: input.y_coefficients[0],
-    }
-  );
-
-  let input = Poly {
-    y_coefficients: vec![random()],
-    yx_coefficients: vec![vec![random(), random()]],
-    x_coefficients: vec![random(), random(), random(), random()],
-    zero_coefficient: random(),
-  };
-  let (diff_x, diff_y) = input.differentiate();
-  assert_eq!(
-    diff_x,
-    Poly {
-      y_coefficients: vec![input.yx_coefficients[0][0]],
-      yx_coefficients: vec![vec![F::from(2) * input.yx_coefficients[0][1]]],
-      x_coefficients: vec![
-        F::from(2) * input.x_coefficients[1],
-        F::from(3) * input.x_coefficients[2],
-        F::from(4) * input.x_coefficients[3],
-      ],
-      zero_coefficient: input.x_coefficients[0],
-    }
-  );
-  assert_eq!(
-    diff_y,
-    Poly {
-      y_coefficients: vec![],
-      yx_coefficients: vec![],
-      x_coefficients: vec![input.yx_coefficients[0][0], input.yx_coefficients[0][1]],
-      zero_coefficient: input.y_coefficients[0],
-    }
-  );
-}

crypto/evrf/ec-gadgets/Cargo.toml

@@ -1,27 +0,0 @@
-[package]
-name = "generalized-bulletproofs-ec-gadgets"
-version = "0.1.0"
-description = "Gadgets for working with an embedded Elliptic Curve in a Generalized Bulletproofs circuit"
-license = "MIT"
-repository = "https://github.com/serai-dex/serai/tree/develop/crypto/fcmps/ec-gadgets"
-authors = ["Luke Parker <lukeparker5132@gmail.com>"]
-keywords = ["bulletproofs", "circuit", "divisors"]
-edition = "2021"
-rust-version = "1.69"
-
-[package.metadata.docs.rs]
-all-features = true
-rustdoc-args = ["--cfg", "docsrs"]
-
-[dependencies]
-std-shims = { path = "../../../common/std-shims", version = "^0.1.1", default-features = false }
-
-generic-array = { version = "1", default-features = false, features = ["alloc"] }
-
-ciphersuite = { path = "../../ciphersuite", version = "0.4", default-features = false }
-
-generalized-bulletproofs-circuit-abstraction = { path = "../circuit-abstraction", default-features = false }
-
-[features]
-std = ["std-shims/std", "ciphersuite/std", "generalized-bulletproofs-circuit-abstraction/std"]
-default = ["std"]

crypto/evrf/ec-gadgets/README.md

@@ -1,3 +0,0 @@
-# Generalized Bulletproofs Circuit Abstraction
-
-A circuit abstraction around `generalized-bulletproofs`.