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`.
This commit is contained in:
Luke Parker
2025-09-03 12:25:37 -04:00
parent 215e41fdb6
commit a141deaf36
124 changed files with 1003 additions and 1211 deletions

View File

@@ -25,12 +25,11 @@ typenum = { version = "1", default-features = false }
prime-field = { path = "../prime-field", default-features = false }
short-weierstrass = { path = "../short-weierstrass", default-features = false }
curve25519-dalek = { version = "4", default-features = false, features = ["legacy_compatibility"] }
dalek-ff-group = { path = "../dalek-ff-group", version = "0.4", default-features = false }
blake2 = { version = "0.11.0-rc.0", default-features = false }
blake2 = { version = "0.11.0-rc.2", default-features = false }
ciphersuite = { path = "../ciphersuite", version = "0.4", default-features = false }
generalized-bulletproofs-ec-gadgets = { git = "https://github.com/monero-oxide/monero-oxide", rev = "a6f8797007e768488568b821435cf5006517a962", default-features = false, optional = true }
generalized-bulletproofs-ec-gadgets = { git = "https://github.com/monero-oxide/monero-oxide", rev = "7216a2e84c7671c167c3d81eafe0d2b1f418f102", default-features = false, optional = true }
[dev-dependencies]
hex = "0.4"