Commit graph

111 commits

Author SHA1 Message Date
Luke Parker
375887bb29
Update licenses 2023-01-11 23:05:31 -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
138f7cdfa4
Correct dev-dependencies for modular-frost 2022-11-14 19:20:56 -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
github-actions[bot]
8e53522780
November 2022 - Rust Nightly Update (#144)
* Update nightly

* Have the latest nightly clippy pass

Co-authored-by: GitHub Actions <>
Co-authored-by: Luke Parker <lukeparker5132@gmail.com>
2022-11-01 00:03:36 -05:00
Luke Parker
e67e406d95
Correct ed448 versioning 2022-10-29 05:25:58 -04:00
Luke Parker
43e38e463f
Update FROST version 2022-10-29 05:14:29 -04:00
Luke Parker
6eaed17952
Inline FROST processing functions into the machines' impls
This was done for the DKG and this similarly cleans up here.
2022-10-29 05:10:07 -04:00
Luke Parker
2379855b31
Create a dedicated crate for the DKG (#141)
* 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
2022-10-29 03:54:42 -05:00
Luke Parker
cbceaff678
Create dedicated message structures for FROST messages (#140)
* 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
2022-10-25 23:17:25 -05:00
Luke Parker
19488cf446
Fill out Cargo.tomls
Updated missing fields/sections, even if some won't be used, to 
standardize.

Also made FROST tests feature-gated.
2022-10-15 23:46:22 -04:00
Luke Parker
9d376d29e1
Bump FROST version to publish a v11-compliant lib 2022-10-15 22:34:12 -04:00
Luke Parker
a0a54eb0de
Update to FROST v11
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.
2022-10-13 00:38:36 -04:00
Luke Parker
2b7c9378c0
Update to FROST v10
Further expands documentation to near-completion.
2022-09-29 07:08:20 -04:00
Luke Parker
7870084b9e
Add further FROST documentation 2022-09-29 06:02:43 -04:00
Luke Parker
ca091a5f04
Expand and correct documentation 2022-09-29 05:25:29 -04:00
Luke Parker
19cd609cba
Use doc_auto_cfg 2022-09-29 04:47:55 -04:00
Luke Parker
8b0f0a3713
Publish an alpha version of the Monero crate (#123)
* 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.
2022-09-29 01:24:33 -05:00
Luke Parker
fd48bbd15e
Initial documentation for the Monero libraries (#122)
* Document all features

* Largely document the Monero libraries

Relevant to https://github.com/serai-dex/serai/issues/103 and likely 
sufficient to get this removed from 
https://github.com/serai-dex/serai/issues/102.
2022-09-28 07:44:49 -05:00
Luke Parker
65c20638ce
fmt/clippy 2022-09-17 04:35:08 -04:00
Luke Parker
7d4fcdea9e
Update FROST Ed448 per request 2022-09-16 12:16:37 -04:00
Luke Parker
31b64b3082
Update according to the latest clippy 2022-09-04 21:23:38 -04:00
Luke Parker
081b9a1975
FROST Ed448 (#107)
* Theoretical ed448 impl

* Fixes

* Basic tests

* More efficient scalarmul

Precomputes a table to minimize additions required.

* Add a torsion test

* Split into a constant and variable time backend

The variable time one is still far too slow, at 53s for the tests (~5s a 
scalarmul). It should be usable as a PoC though.

* Rename unsafe Ed448

It's not only unworthy of the Serai branding and deserves more clarity
in the name.

* Add wide reduction to ed448

* Add Zeroize to Ed448

* Rename Ed448 group.rs to point.rs

* Minor lint to FROST

* Ed448 ciphersuite with 8032 test vector

* Macro out the backend fields

* Slight efficiency improvement to point decompression

* Disable the multiexp test in FROST for Ed448

* fmt + clippy ed448

* Fix an infinite loop in the constant time ed448 backend

* Add b"chal" to the 8032 context string for Ed448

Successfully tests against proposed vectors for the FROST IETF draft.

* Fix fmt and clippy

* Use a tabled pow algorithm in ed448's const backend

* Slight tweaks to variable time backend

Stop from_repr(MODULUS) from passing.

* Use extended points

Almost two orders of magnitude faster.

* Efficient ed448 doubling

* Remove the variable time backend

With the recent performance improvements, the constant time backend is 
now 4x faster than the variable time backend was. While the variable 
time backend remains much faster, and the constant time backend is still 
slow compared to other libraries, it's sufficiently performant now.

The FROST test, which runs a series of multiexps over the curve, does 
take 218.26s while Ristretto takes 1 and secp256k1 takes 4.57s.

While 50x slower than secp256k1 is horrible, it's ~1.5 orders of 
magntiude, which is close enough to the desire stated in 
https://github.com/serai-dex/serai/issues/108 to meet it.

Largely makes this library safe to use.

* Correct constants in ed448

* Rename unsafe-ed448 to minimal-ed448

Enables all FROST tests against it.

* No longer require the hazmat feature to use ed448

* Remove extraneous as_refs
2022-08-29 02:32:59 -05:00
Luke Parker
33ee6b7a02
Bump FROST version 2022-08-26 09:09:18 -04:00
Luke Parker
a8a00598e4
Update to FROST v8 2022-08-26 05:59:43 -04:00
Luke Parker
5d7798c5fb
FROST clippy 2022-08-13 09:46:54 -04:00
Luke Parker
280fc441a7
Lint FROST
Corrects ertrors introduced a couple commits ago as well.
2022-08-13 08:50:59 -04:00
Luke Parker
454b73aec3
Add FROST key promotion
Closes https://github.com/serai-dex/serai/issues/72.

Adds a trait, with a commented impl for a semi-unsafe niche feature, 
which will be used in https://github.com/serai-dex/serai/issues/73.
2022-08-13 08:50:59 -04:00
Luke Parker
885d816309
Use a non-constant generator in FROST 2022-08-13 08:50:59 -04:00
Luke Parker
6f776ff004
Recalculate the group key instead of serializing it
Solves an issue with promotion.
2022-08-13 08:50:59 -04:00
Luke Parker
73205c5f96
Transcript the offset as a point
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.
2022-08-13 08:50:59 -04:00
Luke Parker
a423c23c1e
Use zeroize instead of 0-sets 2022-08-12 01:14:13 -04:00
Luke Parker
797be71eb3
Utilize zeroize (#76)
* 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
2022-08-03 03:25:18 -05:00
Luke Parker
8f76e67f57
Rename dleq-serai to dleq 2022-07-30 18:35:39 -04:00
Luke Parker
755dc84859
Replace rand with rand_core where possible
Turns out rand_core offers OsRng.
2022-07-27 05:45:08 -04:00
Luke Parker
76a7160ea5
Correct clippy warnings
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
2022-07-22 02:35:17 -04:00
Luke Parker
e67033a207 Apply an initial set of rustfmt rules 2022-07-16 15:16:30 -05:00
Luke Parker
5ede5b9e8f
Update the DLEq proof for any amount of generators
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.
2022-07-13 23:29:48 -04:00