Commit graph

135 commits

Author SHA1 Message Date
Luke Parker
e4e4245ee3
One Round DKG (#589)
* Upstream GBP, divisor, circuit abstraction, and EC gadgets from FCMP++

* Initial eVRF implementation

Not quite done yet. It needs to communicate the resulting points and proofs to
extract them from the Pedersen Commitments in order to return those, and then
be tested.

* Add the openings of the PCs to the eVRF as necessary

* Add implementation of secq256k1

* Make DKG Encryption a bit more flexible

No longer requires the use of an EncryptionKeyMessage, and allows pre-defined
keys for encryption.

* Make NUM_BITS an argument for the field macro

* Have the eVRF take a Zeroizing private key

* Initial eVRF-based DKG

* Add embedwards25519 curve

* Inline the eVRF into the DKG library

Due to how we're handling share encryption, we'd either need two circuits or to
dedicate this circuit to the DKG. The latter makes sense at this time.

* Add documentation to the eVRF-based DKG

* Add paragraph claiming robustness

* Update to the new eVRF proof

* Finish routing the eVRF functionality

Still needs errors and serialization, along with a few other TODOs.

* Add initial eVRF DKG test

* Improve eVRF DKG

Updates how we calculcate verification shares, improves performance when
extracting multiple sets of keys, and adds more to the test for it.

* Start using a proper error for the eVRF DKG

* Resolve various TODOs

Supports recovering multiple key shares from the eVRF DKG.

Inlines two loops to save 2**16 iterations.

Adds support for creating a constant time representation of scalars < NUM_BITS.

* Ban zero ECDH keys, document non-zero requirements

* Implement eVRF traits, all the way up to the DKG, for secp256k1/ed25519

* Add Ristretto eVRF trait impls

* Support participating multiple times in the eVRF DKG

* Only participate once per key, not once per key share

* Rewrite processor key-gen around the eVRF DKG

Still a WIP.

* Finish routing the new key gen in the processor

Doesn't touch the tests, coordinator, nor Substrate yet.
`cargo +nightly fmt && cargo +nightly-2024-07-01 clippy --all-features -p serai-processor`
does pass.

* Deduplicate and better document in processor key_gen

* Update serai-processor tests to the new key gen

* Correct amount of yx coefficients, get processor key gen test to pass

* Add embedded elliptic curve keys to Substrate

* Update processor key gen tests to the eVRF DKG

* Have set_keys take signature_participants, not removed_participants

Now no one is removed from the DKG. Only `t` people publish the key however.

Uses a BitVec for an efficient encoding of the participants.

* Update the coordinator binary for the new DKG

This does not yet update any tests.

* Add sensible Debug to key_gen::[Processor, Coordinator]Message

* Have the DKG explicitly declare how to interpolate its shares

Removes the hack for MuSig where we multiply keys by the inverse of their
lagrange interpolation factor.

* Replace Interpolation::None with Interpolation::Constant

Allows the MuSig DKG to keep the secret share as the original private key,
enabling deriving FROST nonces consistently regardless of the MuSig context.

* Get coordinator tests to pass

* Update spec to the new DKG

* Get clippy to pass across the repo

* cargo machete

* Add an extra sleep to ensure expected ordering of `Participation`s

* Update orchestration

* Remove bad panic in coordinator

It expected ConfirmationShare to be n-of-n, not t-of-n.

* Improve documentation on  functions

* Update TX size limit

We now no longer have to support the ridiculous case of having 49 DKG
participations within a 101-of-150 DKG. It does remain quite high due to
needing to _sign_ so many times. It'd may be optimal for parties with multiple
key shares to independently send their preprocesses/shares (despite the
overhead that'll cause with signatures and the transaction structure).

* Correct error in the Processor spec document

* Update a few comments in the validator-sets pallet

* Send/Recv Participation one at a time

Sending all, then attempting to receive all in an expected order, wasn't working
even with notable delays between sending messages. This points to the mempool
not working as expected...

* Correct ThresholdKeys serialization in modular-frost test

* Updating existing TX size limit test for the new DKG parameters

* Increase time allowed for the DKG on the GH CI

* Correct construction of signature_participants in serai-client tests

Fault identified by akil.

* Further contextualize DkgConfirmer by ValidatorSet

Caught by a safety check we wouldn't reuse preprocesses across messages. That
raises the question of we were prior reusing preprocesses (reusing keys)?
Except that'd have caused a variety of signing failures (suggesting we had some
staggered timing avoiding it in practice but yes, this was possible in theory).

* Add necessary calls to set_embedded_elliptic_curve_key in coordinator set rotation tests

* Correct shimmed setting of a secq256k1 key

* cargo fmt

* Don't use `[0; 32]` for the embedded keys in the coordinator rotation test

The key_gen function expects the random values already decided.

* Big-endian secq256k1 scalars

Also restores the prior, safer, Encryption::register function.
2024-09-19 21:43:26 -04:00
Luke Parker
2a05cf3225
June 2024 nightly update
Replaces #571.
2024-06-01 21:46:49 -04:00
Luke Parker
a25e6330bd
Remove DLEq proofs from CLSAG multisig
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).
2024-04-21 23:01:32 -04:00
Luke Parker
c2fffb9887
Correct a couple years of accumulated typos 2023-12-17 02:06:51 -05:00
Luke Parker
065d314e2a
Further expand clippy workspace lints
Achieves a notable amount of reduced async and clones.
2023-12-17 00:04:49 -05:00
Luke Parker
ea3af28139
Add workspace lints 2023-12-17 00:04:47 -05:00
Luke Parker
11fdb6da1d
Coordinator Cleanup (#481)
* 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
2023-12-10 20:21:44 -05:00
Luke Parker
797604ad73
Replace usage of io::Error::new(io::ErrorKind::Other, with io::Error::other
Newly possible with Rust 1.74.
2023-11-19 18:31:37 -05:00
Luke Parker
9eaaa7d2e8
Document H1's mismatch between the FROST preprint and IETF draft 2023-09-15 14:16:15 -04:00
Luke Parker
53d86e2a29
Latest clippy 2023-08-01 02:49:31 -04:00
Luke Parker
c2f32e7882
Update to FROST v14 2023-07-19 15:48:34 -04:00
Luke Parker
c9bb284570
Fix the known instance of #295 2023-07-13 14:02:57 -04:00
Luke Parker
93b1656f86
Meaningful changes from aggressive-clippy
I do want to enable a few specific lints, yet aggressive-clippy as a whole
isn't worthwhile.
2023-07-08 11:29:07 -04:00
Luke Parker
ffea02dfbf
Implement MuSig key aggregation into DKG
Isn't spec compliant due to the lack of a spec to be compliant too.

Slight deviation from the paper by using a unique list instead of a multiset.

Closes #186, progresses #277.
2023-05-10 06:25:40 -04:00
Luke Parker
7a8f8c2d3d
Document panic in FROST 2023-04-24 23:19:23 -04:00
Luke Parker
79aff5d4c8
ff 0.13 (#269)
* 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
2023-03-28 04:38:01 -04:00
Luke Parker
8d4d630e0f
Fully document crypto/ 2023-03-20 20:10:00 -04:00
Luke Parker
918cce3494
Add a proper error to Bitcoin's SignableTransaction::new
Also adds documentation to various parts of bitcoin.
2023-03-17 23:43:32 -04:00
Luke Parker
ba82dac18c
Processor (#259)
* 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
2023-03-16 22:59:40 -04:00
Luke Parker
1e201562df
Correct doc comments re: HTML tags 2023-03-07 05:34:29 -05:00
Luke Parker
837c776297
Make Schnorr modular to its transcript 2023-03-07 05:30:21 -05:00
Luke Parker
e08adcc1ac
Have Ciphersuite re-export Group 2023-03-07 03:46:16 -05:00
Luke Parker
5037962d3c
Rename dkg serialize/deserialize to write/read 2023-03-07 03:37:25 -05:00
Luke Parker
0e8c55e050
Update and remove unused dependencies 2023-03-07 03:06:46 -05:00
Luke Parker
d36fc026dd
Remove unused generic in frost 2023-03-07 02:40:09 -05:00
Luke Parker
0bbf511062
Add 'static/Send/Sync to specific traits in crypto
These were proven necessary by our real world usage.
2023-03-07 02:38:47 -05:00
Luke Parker
2fd5cd8161
3.6.9 Add several tests to the FROST library
Offset signing is now tested. Multi-nonce algorithms are now tested.
Multi-generator nonce algorithms are now tested. More fault cases are now tested
as well.
2023-03-01 08:02:45 -05:00
Luke Parker
c6284b85a4
3.6.8 Simplify offset splitting
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.
2023-03-01 01:06:13 -05:00
Luke Parker
a42a84e1e8
3.6.7 Seal IetfTranscript 2023-03-01 00:42:01 -05:00
Luke Parker
5a3406bb5f
3.6.6 Further document nonces
This was already a largely documented file. While the terminology is
potentially ambiguous, there's not a clearer path perceived at this time.
2023-03-01 00:35:37 -05:00
Luke Parker
62b3036cbd
3.6.5 Document origin of vectors 2023-02-28 23:23:22 -05:00
Luke Parker
6a15b21949
3.6.4 Document inclusion of Ed448 HRAM vector 2023-02-28 23:14:59 -05:00
Luke Parker
39b3452da1
3.6.3 Check commitment encoding
Also extends tests of 3.6.2 and so on.
2023-02-28 21:57:18 -05:00
Luke Parker
7a05466049
3.6.2 Test nonce generation
There's two ways which this could be tested.

1) Preprocess not taking in an arbitrary RNG item, yet the relevant bytes

This would be an unsafe level of refactoring, in my opinion.

2) Test random_nonce and test the passed in RNG eventually ends up at
random_nonce.

This takes the latter route, both verifying random_nonce meets the vectors
and that the FROST machine calls random_nonce properly.
2023-02-28 21:02:12 -05:00
Luke Parker
969a5d94f2
3.6.1 Document rejection of zero nonces 2023-02-24 06:16:22 -05:00
Luke Parker
2d56d24d9c
3.3.3 (cont) Add a dedicated Participant type 2023-02-23 06:50:45 -05:00
Luke Parker
eeca440fa7
Offer a multi-DLEq proof which simply merges challenges for n underlying proofs
This converts proofs from 2n elements to 1+n.

Moves FROST over to it. Additionally, for FROST's binomial nonces, provides
a single DLEq proof (2, not 1+2 elements) by proving the discrete log equality
of their aggregate (with an appropriate binding factor). This may be split back
up depending on later commentary...
2023-01-01 09:16:09 -05:00
Luke Parker
5599a052ad
Run latest nightly clippy
Also runs clippy on the tests and updates the CI accordingly
2023-01-01 04:18:23 -05:00
Luke Parker
5b3c9bf5d0
DKG Blame (#196)
* 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
2023-01-01 01:54:18 -05:00
Luke Parker
da8e7e73e0
Re-organize testing strategy and document Ciphersuite::hash_to_F. 2022-12-24 17:08:22 -05:00
Luke Parker
b8db677d4c
Impl pow_vartime and sqrt on ed libs 2022-12-15 19:23:42 -05:00
Luke Parker
25f1549c6c
Move verify_share to return batch-verifiable statements
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.
2022-12-13 20:31:00 -05:00
Luke Parker
9c65518dc3
Have included return a reference instead of a cloned Vec 2022-12-13 19:40:54 -05:00
Luke Parker
2b042015b5
Replace modular_frost::Curve::hash_to_vec with just hash
There's no reason to copy it to a heap allocated value. The Output implements
AsRef<[u8]> and all uses are satisfied by that.
2022-12-13 19:32:46 -05:00
Luke Parker
783a445a3e
Use a challenge from the FROST transcript as context in the DLEq proofs 2022-12-13 19:27:09 -05:00
Luke Parker
ace7506172
Randomly sort included before doing share verification 2022-12-13 15:41:37 -05:00
Luke Parker
9e82416e7d
Correct derives on errors 2022-12-09 09:50:00 -05:00
Luke Parker
af86b7a499
Support caching preprocesses in FROST (#190)
* 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
2022-12-08 19:04:35 -05:00
Luke Parker
84de427d72
Fix https://github.com/serai-dex/serai/issues/150 2022-11-10 22:35:09 -05:00
Luke Parker
8de465af87
Have Transcript::append_message take in AsRef<[u8]>, not &[u8]
Simplifies calling it.
2022-11-05 18:43:36 -04:00