This helps identify where the various functionalities are used, or rather, not
used. The `Ciphersuite` trait present in `patches/ciphersuite`, facilitating
the entire FCMP++ tree, only requires the markers _and_ canonical point
decoding. I've opened a PR to upstream such a trait into `group`
(https://github.com/zkcrypto/group/pull/68).
`WrappedGroup` is still justified for as long as `Group::generator` exists.
Moving `::generator()` to its own trait, on an independent structure (upstream)
would be massively appreciated. @tarcieri also wanted to update from
`fn generator()` to `const GENERATOR`, which would encourage further discussion
on https://github.com/zkcrypto/group/issues/32 and
https://github.com/zkcrypto/group/issues/45, which have been stagnant.
The `Id` trait is occasionally used yet really should be first off the chopping
block.
Finally, `WithPreferredHash` is only actually used around a third of the time,
which more than justifies it being a separate trait.
---
Updates `dalek_ff_group::Scalar` to directly re-export
`curve25519_dalek::Scalar`, as without issue. `dalek_ff_group::RistrettoPoint`
also could be replaced with an export of `curve25519_dalek::RistrettoPoint`,
yet the coordinator relies on how we implemented `Hash` on it for the hell of
it so it isn't worth it at this time. `dalek_ff_group::EdwardsPoint` can't be
replaced for an re-export of `curve25519_dalek::SubgroupPoint` as it doesn't
implement `zeroize`, `subtle` traits within a released, non-yanked version.
Relevance to https://github.com/serai-dex/serai/issues/201 and
https://github.com/dalek-cryptography/curve25519-dalek/issues/811#issuecomment-3247732746.
Also updates the `Ristretto` ciphersuite to prefer `Blake2b-512` over
`SHA2-512`. In order to maintain compliance with FROST's IETF standard,
`modular-frost` defines its own ciphersuite for Ristretto which still uses
`SHA2-512`.
The transcript transcripted the group key _plus_ the offset, when it should've
only transcripted the group key as the declared group key already had the
offset applied. This has been fixed.
This had ill-defined properties on Clone, as a mask could be sent multiple times
(unintended) and multiple algorithms may receive the same mask from a singular
sender.
Requires removing the Clone bound within modular-frost and expanding the test
helpers accordingly.
This was not raised in the audit yet upon independent review.
1) Removes the key image DLEq on the Monero side of things, as the produced
signature share serves as a DLEq for it.
2) Removes the nonce DLEqs from modular-frost as they're unnecessary for
monero-serai. Updates documentation accordingly.
Without the proof the nonces are internally consistent, the produced signatures
from modular-frost can be argued as a batch-verifiable CP93 DLEq (R0, R1, s),
or as a GSP for the CP93 DLEq statement (which naturally produces (R0, R1, s)).
The lack of proving the nonces consistent does make the process weaker, yet
it's also unnecessary for the class of protocols this is intended to service.
To provide DLEqs for the nonces would be to provide PoKs for the nonce
commitments (in the traditional Schnorr case).
* Move logic for evaluating if a cosign should occur to its own file
Cleans it up and makes it more robust.
* Have expected_next_batch return an error instead of retrying
While convenient to offer an error-free implementation, it potentially caused
very long lived lock acquisitions in handle_processor_message.
* Unify and clean DkgConfirmer and DkgRemoval
Does so via adding a new file for the common code, SigningProtocol.
Modifies from_cache to return the preprocess with the machine, as there's no
reason not to. Also removes an unused Result around the type.
Clarifies the security around deterministic nonces, removing them for
saved-to-disk cached preprocesses. The cached preprocesses are encrypted as the
DB is not a proper secret store.
Moves arguments always present in the protocol from function arguments into the
struct itself.
Removes the horribly ugly code in DkgRemoval, fixing multiple issues present
with it which would cause it to fail on use.
* Set SeraiBlockNumber in cosign.rs as it's used by the cosigning protocol
* Remove unnecessary Clone from lambdas in coordinator
* Remove the EventDb from Tributary scanner
We used per-Transaction DB TXNs so on error, we don't have to rescan the entire
block yet only the rest of it. We prevented scanning multiple transactions by
tracking which we already had.
This is over-engineered and not worth it.
* Implement borsh for HasEvents, removing the manual encoding
* Merge DkgConfirmer and DkgRemoval into signing_protocol.rs
Fixes a bug in DkgConfirmer which would cause it to improperly handle indexes
if any validator had multiple key shares.
* Strictly type DataSpecification's Label
* Correct threshold_i_map_to_keys_and_musig_i_map
It didn't include the participant's own index and accordingly was offset.
* Create TributaryBlockHandler
This struct contains all variables prior passed to handle_block and stops them
from being passed around again and again.
This also ensures fatal_slash is only called while handling a block, as needed
as it expects to operate under perfect consensus.
* Inline accumulate, store confirmation nonces with shares
Inlining accumulate makes sense due to the amount of data accumulate needed to
be passed.
Storing confirmation nonces with shares ensures that both are available or
neither. Prior, one could be yet the other may not have been (requiring an
assert in runtime to ensure we didn't bungle it somehow).
* Create helper functions for handling DkgRemoval/SubstrateSign/Sign Tributary TXs
* Move Label into SignData
All of our transactions which use SignData end up with the same common usage
pattern for Label, justifying this.
Removes 3 transactions, explicitly de-duplicating their handlers.
* Remove CurrentlyCompletingKeyPair for the non-contextual DkgKeyPair
* Remove the manual read/write for TributarySpec for borsh
This struct doesn't have any optimizations booned by the manual impl. Using
borsh reduces our scope.
* Use temporary variables to further minimize LoC in tributary handler
* Remove usage of tuples for non-trivial Tributary transactions
* Remove serde from dkg
serde could be used to deserialize intenrally inconsistent objects which could
lead to panics or faults.
The BorshDeserialize derives have been replaced with a manual implementation
which won't produce inconsistent objects.
* Abstract Future generics using new trait definitions in coordinator
* Move published_signed_transaction to tributary/mod.rs to reduce the size of main.rs
* Split coordinator/src/tributary/mod.rs into spec.rs and transaction.rs
* Partial move to ff 0.13
It turns out the newly released k256 0.12 isn't on ff 0.13, preventing further
work at this time.
* Update all crates to work on ff 0.13
The provided curves still need to be expanded to fit the new API.
* Finish adding dalek-ff-group ff 0.13 constants
* Correct FieldElement::product definition
Also stops exporting macros.
* Test most new parts of ff 0.13
* Additionally test ff-group-tests with BLS12-381 and the pasta curves
We only tested curves from RustCrypto. Now we test a curve offered by zk-crypto,
the group behind ff/group, and the pasta curves, which is by Zcash (though
Zcash developers are also behind zk-crypto).
* Finish Ed448
Fully specifies all constants, passes all tests in ff-group-tests, and finishes moving to ff-0.13.
* Add RustCrypto/elliptic-curves to allowed git repos
Needed due to k256/p256 incorrectly defining product.
* Finish writing ff 0.13 tests
* Add additional comments to dalek
* Further comments
* Update ethereum-serai to ff 0.13
* Initial work on a message box
* Finish message-box (untested)
* Expand documentation
* Embed the recipient in the signature challenge
Prevents a message from A -> B from being read as from A -> C.
* Update documentation by bifurcating sender/receiver
* Panic on receiving an invalid signature
If we've received an invalid signature in an authenticated system, a
service is malicious, critically faulty (equivalent to malicious), or
the message layer has been compromised (or is otherwise critically
faulty).
Please note a receiver who handles a message they shouldn't will trigger
this. That falls under being critically faulty.
* Documentation and helper methods
SecureMessage::new and SecureMessage::serialize.
Secure Debug for MessageBox.
* Have SecureMessage not be serialized by default
Allows passing around in-memory, if desired, and moves the error from
decrypt to new (which performs deserialization).
Decrypt no longer has an error since it panics if given an invalid
signature, due to this being intranet code.
* Explain and improve nonce handling
Includes a missing zeroize call.
* Rebase to latest develop
Updates to transcript 0.2.0.
* Add a test for the MessageBox
* Export PrivateKey and PublicKey
* Also test serialization
* Add a key_gen binary to message_box
* Have SecureMessage support Serde
* Add encrypt_to_bytes and decrypt_from_bytes
* Support String ser via base64
* Rename encrypt/decrypt to encrypt_bytes/decrypt_to_bytes
* Directly operate with values supporting Borsh
* Use bincode instead of Borsh
By staying inside of serde, we'll support many more structs. While
bincode isn't canonical, we don't need canonicity on an authenticated,
internal system.
* Turn PrivateKey, PublicKey into structs
Uses Zeroizing for the PrivateKey per #150.
* from_string functions intended for loading from an env
* Use &str for PublicKey from_string (now from_str)
The PrivateKey takes the String to take ownership of its memory and
zeroize it. That isn't needed with PublicKeys.
* Finish updating from develop
* Resolve warning
* Use ZeroizingAlloc on the key_gen binary
* Move message-box from crypto/ to common/
* Move key serialization functions to ser
* add/remove functions in MessageBox
* Implement Hash on dalek_ff_group Points
* Make MessageBox generic to its key
Exposes a &'static str variant for internal use and a RistrettoPoint
variant for external use.
* Add Private to_string as deprecated
Stub before more competent tooling is deployed.
* Private to_public
* Test both Internal and External MessageBox, only use PublicKey in the pub API
* Remove panics on invalid signatures
Leftover from when this was solely internal which is now unsafe.
* Chicken scratch a Scanner task
* Add a write function to the DKG library
Enables writing directly to a file.
Also modifies serialize to return Zeroizing<Vec<u8>> instead of just Vec<u8>.
* Make dkg::encryption pub
* Remove encryption from MessageBox
* Use a 64-bit block number in Substrate
We use a 64-bit block number in general since u32 only works for 120 years
(with a 1 second block time). As some chains even push the 1 second threshold,
especially ones based on DAG consensus, this becomes potentially as low as 60
years.
While that should still be plenty, it's not worth wondering/debating. Since
Serai uses 64-bit block numbers elsewhere, this ensures consistency.
* Misc crypto lints
* Get the scanner scratch to compile
* Initial scanner test
* First few lines of scheduler
* Further work on scheduler, solidify API
* Define Scheduler TX format
* Branch creation algorithm
* Document when the branch algorithm isn't perfect
* Only scanned confirmed blocks
* Document Coin
* Remove Canonical/ChainNumber from processor
The processor should be abstracted from canonical numbers thanks to the
coordinator, making this unnecessary.
* Add README documenting processor flow
* Use Zeroize on substrate primitives
* Define messages from/to the processor
* Correct over-specified versioning
* Correct build re: in_instructions::primitives
* Debug/some serde in crypto/
* Use a struct for ValidatorSetInstance
* Add a processor key_gen task
Redos DB handling code.
* Replace trait + impl with wrapper struct
* Add a key confirmation flow to the key gen task
* Document concerns on key_gen
* Start on a signer task
* Add Send to FROST traits
* Move processor lib.rs to main.rs
Adds a dummy main to reduce clippy dead_code warnings.
* Further flesh out main.rs
* Move the DB trait to AsRef<[u8]>
* Signer task
* Remove a panic in bitcoin when there's insufficient funds
Unchecked underflow.
* Have Monero's mine_block mine one block, not 10
It was initially a nicety to deal with the 10 block lock. C::CONFIRMATIONS
should be used for that instead.
* Test signer
* Replace channel expects with log statements
The expects weren't problematic and had nicer code. They just clutter test
output.
* Remove the old wallet file
It predates the coordinator design and shouldn't be used.
* Rename tests/scan.rs to tests/scanner.rs
* Add a wallet test
Complements the recently removed wallet file by adding a test for the scanner,
scheduler, and signer together.
* Work on a run function
Triggers a clippy ICE.
* Resolve clippy ICE
The issue was the non-fully specified lambda in signer.
* Add KeyGenEvent and KeyGenOrder
Needed so we get KeyConfirmed messages from the key gen task.
While we could've read the CoordinatorMessage to see that, routing through the
key gen tasks ensures we only handle it once it's been successfully saved to
disk.
* Expand scanner test
* Clarify processor documentation
* Have the Scanner load keys on boot/save outputs to disk
* Use Vec<u8> for Block ID
Much more flexible.
* Panic if we see the same output multiple times
* Have the Scanner DB mark itself as corrupt when doing a multi-put
This REALLY should be a TX. Since we don't have a TX API right now, this at
least offers detection.
* Have DST'd DB keys accept AsRef<[u8]>
* Restore polling all signers
Writes a custom future to do so.
Also loads signers on boot using what the scanner claims are active keys.
* Schedule OutInstructions
Adds a data field to Payment.
Also cleans some dead code.
* Panic if we create an invalid transaction
Saves the TX once it's successfully signed so if we do panic, we have a copy.
* Route coordinator messages to their respective signer
Requires adding key to the SignId.
* Send SignTransaction orders for all plans
* Add a timer to retry sign_plans when prepare_send fails
* Minor fmt'ing
* Basic Fee API
* Move the change key into Plan
* Properly route activation_number
* Remove ScannerEvent::Block
It's not used under current designs
* Nicen logs
* Add utilities to get a block's number
* Have main issue AckBlock
Also has a few misc lints.
* Parse instructions out of outputs
* Tweak TODOs and remove an unwrap
* Update Bitcoin max input/output quantity
* Only read one piece of data from Monero
Due to output randomization, it's infeasible.
* Embed plan IDs into the TXs they create
We need to stop attempting signing if we've already signed a protocol. Ideally,
any one of the participating signers should be able to provide a proof the TX
was successfully signed. We can't just run a second signing protocol though as
a single malicious signer could complete the TX signature, and publish it,
yet not complete the secondary signature.
The TX itself has to be sufficient to show that the TX matches the plan. This
is done by embedding the ID, so matching addresses/amounts plans are
distinguished, and by allowing verification a TX actually matches a set of
addresses/amounts.
For Monero, this will need augmenting with the ephemeral keys (or usage of a
static seed for them).
* Don't use OP_RETURN to encode the plan ID on Bitcoin
We can use the inputs to distinguih identical-output plans without issue.
* Update OP_RETURN data access
It's not required to be the last output.
* Add Eventualities to Monero
An Eventuality is an effective equivalent to a SignableTransaction. That is
declared not by the inputs it spends, yet the outputs it creates.
Eventualities are also bound to a 32-byte RNG seed, enabling usage of a
hash-based identifier in a SignableTransaction, allowing multiple
SignableTransactions with the same output set to have different Eventualities.
In order to prevent triggering the burning bug, the RNG seed is hashed with
the planned-to-be-used inputs' output keys. While this does bind to them, it's
only loosely bound. The TX actually created may use different inputs entirely
if a forgery is crafted (which requires no brute forcing).
Binding to the key images would provide a strong binding, yet would require
knowing the key images, which requires active communication with the spend
key.
The purpose of this is so a multisig can identify if a Transaction the entire
group planned has been executed by a subset of the group or not. Once a plan
is created, it can have an Eventuality made. The Eventuality's extra is able
to be inserted into a HashMap, so all new on-chain transactions can be
trivially checked as potential candidates. Once a potential candidate is found,
a check involving ECC ops can be performed.
While this is arguably a DoS vector, the underlying Monero blockchain would
need to be spammed with transactions to trigger it. Accordingly, it becomes
a Monero blockchain DoS vector, when this code is written on the premise
of the Monero blockchain functioning. Accordingly, it is considered handled.
If a forgery does match, it must have created the exact same outputs the
multisig would've. Accordingly, it's argued the multisig shouldn't mind.
This entire suite of code is only necessary due to the lack of outgoing
view keys, yet it's able to avoid an interactive protocol to communicate
key images on every single received output.
While this could be locked to the multisig feature, there's no practical
benefit to doing so.
* Add support for encoding Monero address to instructions
* Move Serai's Monero address encoding into serai-client
serai-client is meant to be a single library enabling using Serai. While it was
originally written as an RPC client for Serai, apps actually using Serai will
primarily be sending transactions on connected networks. Sending those
transactions require proper {In, Out}Instructions, including proper address
encoding.
Not only has address encoding been moved, yet the subxt client is now behind
a feature. coin integrations have their own features, which are on by default.
primitives are always exposed.
* Reorganize file layout a bit, add feature flags to processor
* Tidy up ETH Dockerfile
* Add Bitcoin address encoding
* Move Bitcoin::Address to serai-client's
* Comment where tweaking needs to happen
* Add an API to check if a plan was completed in a specific TX
This allows any participating signer to submit the TX ID to prevent further
signing attempts.
Also performs some API cleanup.
* Minimize FROST dependencies
* Use a seeded RNG for key gen
* Tweak keys from Key gen
* Test proper usage of Branch/Change addresses
Adds a more descriptive error to an error case in decoys, and pads Monero
payments as needed.
* Also test spending the change output
* Add queued_plans to the Scheduler
queued_plans is for payments to be issued when an amount appears, yet the
amount is currently pre-fee. One the output is actually created, the
Scheduler should be notified of the amount it was created with, moving from
queued_plans to plans under the actual amount.
Also tightens debug_asserts to asserts for invariants which may are at risk of
being exclusive to prod.
* Add missing tweak_keys call
* Correct decoy selection height handling
* Add a few log statements to the scheduler
* Simplify test's get_block_number
* Simplify, while making more robust, branch address handling in Scheduler
* Have fees deducted from payments
Corrects Monero's handling of fees when there's no change address.
Adds a DUST variable, as needed due to 1_00_000_000 not being enough to pay
its fee on Monero.
* Add comment to Monero
* Consolidate BTC/XMR prepare_send code
These aren't fully consolidated. We'd need a SignableTransaction trait for
that. This is a lot cleaner though.
* Ban integrated addresses
The reasoning why is accordingly documented.
* Tidy TODOs/dust handling
* Update README TODO
* Use a determinisitic protocol version in Monero
* Test rebuilt KeyGen machines function as expected
* Use a more robust KeyGen entropy system
* Add DB TXNs
Also load entropy from env
* Add a loop for processing messages from substrate
Allows detecting if we're behind, and if so, waiting to handle the message
* Set Monero MAX_INPUTS properly
The previous number was based on an old hard fork. With the ring size having
increased, transactions have since got larger.
* Distinguish TODOs into TODO and TODO2s
TODO2s are for after protonet
* Zeroize secret share repr in ThresholdCore write
* Work on Eventualities
Adds serialization and stops signing when an eventuality is proven.
* Use a more robust DB key schema
* Update to {k, p}256 0.12
* cargo +nightly clippy
* cargo update
* Slight message-box tweaks
* Update to recent Monero merge
* Add a Coordinator trait for communication with coordinator
* Remove KeyGenHandle for just KeyGen
While KeyGen previously accepted instructions over a channel, this breaks the
ack flow needed for coordinator communication. Now, KeyGen is the direct object
with a handle() function for messages.
Thankfully, this ended up being rather trivial for KeyGen as it has no
background tasks.
* Add a handle function to Signer
Enables determining when it's finished handling a CoordinatorMessage and
therefore creating an acknowledgement.
* Save transactions used to complete eventualities
* Use a more intelligent sleep in the signer
* Emit SignedTransaction with the first ID *we can still get from our node*
* Move Substrate message handling into the new coordinator recv loop
* Add handle function to Scanner
* Remove the plans timer
Enables ensuring the ordring on the handling of plans.
* Remove the outputs function which panicked if a precondition wasn't met
The new API only returns outputs upon satisfaction of the precondition.
* Convert SignerOrder::SignTransaction to a function
* Remove the key_gen object from sign_plans
* Refactor out get_fee/prepare_send into dedicated functions
* Save plans being signed to the DB
* Reload transactions being signed on boot
* Stop reloading TXs being signed (and report it to peers)
* Remove message-box from the processor branch
We don't use it here yet.
* cargo +nightly fmt
* Move back common/zalloc
* Update subxt to 0.27
* Zeroize ^1.5, not 1
* Update GitHub workflow
* Remove usage of SignId in completed
This wasn't done prior to be 'leaderless', as now the participant with the
lowest ID has an extra step, yet this is still trivial. There's also notable
performance benefits to not taking the previous dividing approach, which
performed an exp.
* Standardize the DLEq serialization function naming
They mismatched from the rest of the project.
This commit is technically incomplete as it doesn't update the dkg crate.
* Rewrite DKG encryption to enable per-message decryption without side effects
This isn't technically true as I already know a break in this which I'll
correct for shortly.
Does update documentation to explain the new scheme. Required for blame.
* Add a verifiable system for blame during the FROST DKG
Previously, if sent an invalid key share, the participant would realize that
and could accuse the sender. Without further evidence, either the accuser
or the accused could be guilty. Now, the accuser has a proof the accused is
in the wrong.
Reworks KeyMachine to return BlameMachine. This explicitly acknowledges how
locally complete keys still need group acknowledgement before the protocol
can be complete and provides a way for others to verify blame, even after a
locally successful run.
If any blame is cast, the protocol is no longer considered complete-able
(instead aborting). Further accusations of blame can still be handled however.
Updates documentation on network behavior.
Also starts to remove "OnDrop". We now use Zeroizing for anything which should
be zeroized on drop. This is a lot more piece-meal and reduces clones.
* Tweak Zeroizing and Debug impls
Expands Zeroizing to be more comprehensive.
Also updates Zeroizing<CachedPreprocess([u8; 32])> to
CachedPreprocess(Zeroizing<[u8; 32]>) so zeroizing is the first thing done
and last step before exposing the copy-able [u8; 32].
Removes private keys from Debug.
* Fix a bug where adversaries could claim to be using another user's encryption keys to learn their messages
Mentioned a few commits ago, now fixed.
This wouldn't have affected Serai, which aborts on failure, nor any DKG
currently supported. It's just about ensuring the DKG encryption is robust and
proper.
* Finish moving dleq from ser/deser to write/read
* Add tests for dkg blame
* Add a FROST test for invalid signature shares
* Batch verify encrypted messages' ephemeral keys' PoP
While the previous construction achieved n/2 average detection,
this will run in log2(n). Unfortunately, the need to keep entropy
around (or take in an RNG here) remains.
* Remove the explicit included participants from FROST
Now, whoever submits preprocesses becomes the signing set. Better separates
preprocess from sign, at the cost of slightly more annoying integrations
(Monero needs to now independently lagrange/offset its key images).
* Support caching preprocesses
Closes https://github.com/serai-dex/serai/issues/40.
I *could* have added a serialization trait to Algorithm and written a ton of
data to disk, while requiring Algorithm implementors also accept such work.
Instead, I moved preprocess to a seeded RNG (Chacha20) which should be as
secure as the regular RNG. Rebuilding from cache simply loads the previously
used Chacha seed, making the Algorithm oblivious to the fact it's being
rebuilt from a cache. This removes any requirements for it to be modified
while guaranteeing equivalency.
This builds on the last commit which delayed determining the signing set till
post-preprocess acquisition. Unfortunately, that commit did force preprocess
from ThresholdView to ThresholdKeys which had visible effects on Monero.
Serai will actually need delayed set determination for #163, and overall,
it remains better, hence it's inclusion.
* Document FROST preprocess caching
* Update ethereum to new FROST
* Fix bug in Monero offset calculation and update processor
* Add dkg crate
* Remove F_len and G_len
They're generally no longer used.
* Replace hash_to_vec with a provided method around associated type H: Digest
Part of trying to minimize this trait so it can be moved elsewhere. Vec,
which isn't std, may have been a blocker.
* Encrypt secret shares within the FROST library
Reduces requirements on callers in order to be correct.
* Update usage of Zeroize within FROST
* Inline functions in key_gen
There was no reason to have them separated as they were. sign probably
has the same statement available, yet that isn't the focus right now.
* Add a ciphersuite package which provides hash_to_F
* Set the Ciphersuite version to something valid
* Have ed448 export Scalar/FieldElement/Point at the top level
* Move FROST over to Ciphersuite
* Correct usage of ff in ciphersuite
* Correct documentation handling
* Move Schnorr signatures to their own crate
* Remove unused feature from schnorr
* Fix Schnorr tests
* Split DKG into a separate crate
* Add serialize to Commitments and SecretShare
Helper for buf = vec![]; .write(buf).unwrap(); buf
* Move FROST over to the new dkg crate
* Update Monero lib to latest FROST
* Correct ethereum's usage of features
* Add serialize to GeneratorProof
* Add serialize helper function to FROST
* Rename AddendumSerialize to WriteAddendum
* Update processor
* Slight fix to processor
* Create message types for FROST key gen
Taking in reader borrows absolutely wasn't feasible. Now, proper types
which can be read (and then passed directly, without a mutable borrow)
exist for key_gen. sign coming next.
* Move FROST signing to messages, not Readers/Writers/Vec<u8>
Also takes the nonce handling code and makes a dedicated file for it,
aiming to resolve complex types and make the code more legible by
replacing its previously inlined state.
* clippy
* Update FROST tests
* read_signature_share
* Update the Monero library to the new FROST packages
* Update processor to latest FROST
* Tweaks to terminology and documentation
Ensures random functions never return zero. This, combined with a check
commitments aren't 0, causes no serialized elements to be 0.
Also directly reads their vectors.
* Label the version as an alpha
* Add versions to Cargo.tomls
* Update to Zeroize 1.5
* Drop patch versions from monero-serai Cargo.toml
* Add a repository field
* Move generators to OUT_DIR
IIRC, I didn't do this originally as it constantly re-generated them.
Unfortunately, since cargo is complaining about .generators, we have to.
* Remove Timelock::fee_weight
Transaction::fee_weight's has a comment, "Assumes Timelock::None since
this library won't let you create a TX with a timelock". Accordingly,
this is dead code.
Potentially improves privacy with the reversion to a coordinator
setting, where the coordinator is the only party with the offset. While
any signer (or anyone) can claim key A relates to B, they can't prove it
without the discrete log of the offset. This enables creating a signing
process without a known offset, while maintaining a consistent
transcript format.
Doesn't affect security given a static generator. Does have a slight
effect on performance.
* Apply Zeroize to nonces used in Bulletproofs
Also makes bit decomposition constant time for a given amount of
outputs.
* Fix nonce reuse for single-signer CLSAG
* Attach Zeroize to most structures in Monero, and ZOnDrop to anything with private data
* Zeroize private keys and nonces
* Merge prepare_outputs and prepare_transactions
* Ensure CLSAG is constant time
* Pass by borrow where needed, bug fixes
The past few commitments have been one in-progress chunk which I've
broken up as best read.
* Add Zeroize to FROST structs
Still needs to zeroize internally, yet next step. Not quite as
aggressive as Monero, partially due to the limitations of HashMaps,
partially due to less concern about metadata, yet does still delete a
few smaller items of metadata (group key, context string...).
* Remove Zeroize from most Monero multisig structs
These structs largely didn't have private data, just fields with private
data, yet those fields implemented ZeroizeOnDrop making them already
covered. While there is still traces of the transaction left in RAM,
fully purging that was never the intent.
* Use Zeroize within dleq
bitvec doesn't offer Zeroize, so a manual zeroing has been implemented.
* Use Zeroize for random_nonce
It isn't perfect, due to the inability to zeroize the digest, and due to
kp256 requiring a few transformations. It does the best it can though.
Does move the per-curve random_nonce to a provided one, which is allowed
as of https://github.com/cfrg/draft-irtf-cfrg-frost/pull/231.
* Use Zeroize on FROST keygen/signing
* Zeroize constant time multiexp.
* Correct when FROST keygen zeroizes
* Move the FROST keys Arc into FrostKeys
Reduces amount of instances in memory.
* Manually implement Debug for FrostCore to not leak the secret share
* Misc bug fixes
* clippy + multiexp test bug fixes
* Correct FROST key gen share summation
It leaked our own share for ourself.
* Fix cross-group DLEq tests
Currently intended to be done with:
cargo clippy --features "recommended merlin batch serialize experimental
ed25519 ristretto p256 secp256k1 multisig" -- -A clippy::type_complexity
-A dead_code
The two-generator limit wasn't required nor beneficial. This does
theoretically optimize FROST, yet not for any current constructions. A
follow up proof which would optimize current constructions has been
noted in #38.
Adds explicit no_std support to the core DLEq proof.
Closes#34.
