Commit Graph

8 Commits

Author SHA1 Message Date
Luke Parker
10c126ad92 Misc updates 2025-09-18 17:41:25 -04:00
Luke Parker
a141deaf36 Smash the singular Ciphersuite trait into multiple
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`.
2025-09-03 13:50:20 -04:00
Luke Parker
5526b8d439 Use SEC1 for the encoding of secq256k1 points, like secp256k1 does 2025-08-28 23:52:05 -04:00
Luke Parker
beac35c119 Introduce the complete point addition formulas to short-weierstrass 2025-08-28 23:16:16 -04:00
Luke Parker
62bb75e09a Move secq256k1 to short-weierstrass 2025-08-28 23:07:22 -04:00
Luke Parker
45bd376c08 Fix handling of prime/composite-order curves within short-weierstrass 2025-08-28 22:31:33 -04:00
Luke Parker
da190759a9 Move embedwards25519 over to short-weierstrass 2025-08-28 22:08:17 -04:00
Luke Parker
f2d399ba1e Add crate for working with short Weierstrass elliptic curves 2025-08-28 08:20:31 -04:00