absolutebi/serai
1
0
Fork 0
mirror of https://github.com/serai-dex/serai.git synced 2025-12-08 20:29:23 +00:00
Code Issues Packages Projects Releases Wiki Activity

Smash the singular Ciphersuite trait into multiple

Browse Source 
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
Download Patch File Download Diff File Expand all files Collapse all files

6
processor/bitcoin/src/key_gen.rs
View File

@@ -1,4 +1,4 @@
use ciphersuite::{group::GroupEncoding, Ciphersuite};
use ciphersuite::{group::GroupEncoding, *};
use dkg::{ThresholdKeys, Curves, Secp256k1};
use crate::{primitives::x_coord_to_even_point, scan::scanner};
@@ -18,7 +18,7 @@ impl key_gen::KeyGenParams for KeyGenParams {
}
fn encode_key(
key: <<Self::ExternalNetworkCiphersuite as Curves>::ToweringCurve as Ciphersuite>::G,
key: <<Self::ExternalNetworkCiphersuite as Curves>::ToweringCurve as WrappedGroup>::G,
) -> Vec<u8> {
let key = key.to_bytes();
let key: &[u8] = key.as_ref();
@@ -28,7 +28,7 @@ impl key_gen::KeyGenParams for KeyGenParams {
fn decode_key(
key: &[u8],
) -> Option<<<Self::ExternalNetworkCiphersuite as Curves>::ToweringCurve as Ciphersuite>::G> {
) -> Option<<<Self::ExternalNetworkCiphersuite as Curves>::ToweringCurve as WrappedGroup>::G> {
x_coord_to_even_point(key)
}
}

4
processor/bitcoin/src/primitives/block.rs
View File

@@ -1,7 +1,7 @@
use core::fmt;
use std::collections::HashMap;
use ciphersuite::Ciphersuite;
use ciphersuite::*;
use ciphersuite_kp256::Secp256k1;
use bitcoin_serai::bitcoin::block::{Header, Block as BBlock};
@@ -35,7 +35,7 @@ impl<D: Db> fmt::Debug for Block<D> {
impl<D: Db> primitives::Block for Block<D> {
type Header = BlockHeader;
type Key = <Secp256k1 as Ciphersuite>::G;
type Key = <Secp256k1 as WrappedGroup>::G;
type Address = Address;
type Output = Output;
type Eventuality = Eventuality;

4
processor/bitcoin/src/primitives/mod.rs
View File

@@ -1,4 +1,4 @@
use ciphersuite::Ciphersuite;
use ciphersuite::*;
use ciphersuite_kp256::Secp256k1;
use bitcoin_serai::bitcoin::key::{Parity, XOnlyPublicKey};
@@ -7,7 +7,7 @@ pub(crate) mod output;
pub(crate) mod transaction;
pub(crate) mod block;
pub(crate) fn x_coord_to_even_point(key: &[u8]) -> Option<<Secp256k1 as Ciphersuite>::G> {
pub(crate) fn x_coord_to_even_point(key: &[u8]) -> Option<<Secp256k1 as WrappedGroup>::G> {
if key.len() != 32 {
None?
};

12
processor/bitcoin/src/primitives/output.rs
View File

@@ -1,6 +1,6 @@
use std::io;
use ciphersuite::Ciphersuite;
use ciphersuite::*;
use ciphersuite_kp256::Secp256k1;
use bitcoin_serai::{
@@ -55,7 +55,7 @@ pub(crate) struct Output {
impl Output {
pub(crate) fn new(
getter: &impl Get,
key: <Secp256k1 as Ciphersuite>::G,
key: <Secp256k1 as WrappedGroup>::G,
tx: &Transaction,
output: WalletOutput,
) -> Self {
@@ -71,7 +71,7 @@ impl Output {
}
pub(crate) fn new_with_presumed_origin(
key: <Secp256k1 as Ciphersuite>::G,
key: <Secp256k1 as WrappedGroup>::G,
tx: &Transaction,
presumed_origin: Option<Address>,
output: WalletOutput,
@@ -88,7 +88,7 @@ impl Output {
}
}
impl ReceivedOutput<<Secp256k1 as Ciphersuite>::G, Address> for Output {
impl ReceivedOutput<<Secp256k1 as WrappedGroup>::G, Address> for Output {
type Id = OutputId;
type TransactionId = [u8; 32];
@@ -108,7 +108,7 @@ impl ReceivedOutput<<Secp256k1 as Ciphersuite>::G, Address> for Output {
res
}
fn key(&self) -> <Secp256k1 as Ciphersuite>::G {
fn key(&self) -> <Secp256k1 as WrappedGroup>::G {
// We read the key from the script pubkey so we don't have to independently store it
let script = &self.output.output().script_pubkey;
@@ -121,7 +121,7 @@ impl ReceivedOutput<<Secp256k1 as Ciphersuite>::G, Address> for Output {
.expect("last item in scanned v1 Taproot script wasn't a valid x-only public key");
// The output's key minus the output's offset is the root key
key - (<Secp256k1 as Ciphersuite>::G::GENERATOR * self.output.offset())
key - (<Secp256k1 as WrappedGroup>::G::GENERATOR * self.output.offset())
}
fn presumed_origin(&self) -> Option<Address> {

16
processor/bitcoin/src/scan.rs
View File

@@ -1,6 +1,6 @@
use std::{sync::LazyLock, collections::HashMap};
use ciphersuite::Ciphersuite;
use ciphersuite::*;
use ciphersuite_kp256::Secp256k1;
use bitcoin_serai::{
@@ -20,20 +20,20 @@ use primitives::OutputType;
use crate::hash_bytes;
// TODO: Bitcoin HD derivation, instead of these bespoke labels?
static BRANCH_BASE_OFFSET: LazyLock<<Secp256k1 as Ciphersuite>::F> =
static BRANCH_BASE_OFFSET: LazyLock<<Secp256k1 as WrappedGroup>::F> =
LazyLock::new(|| Secp256k1::hash_to_F(b"branch"));
static CHANGE_BASE_OFFSET: LazyLock<<Secp256k1 as Ciphersuite>::F> =
static CHANGE_BASE_OFFSET: LazyLock<<Secp256k1 as WrappedGroup>::F> =
LazyLock::new(|| Secp256k1::hash_to_F(b"change"));
static FORWARD_BASE_OFFSET: LazyLock<<Secp256k1 as Ciphersuite>::F> =
static FORWARD_BASE_OFFSET: LazyLock<<Secp256k1 as WrappedGroup>::F> =
LazyLock::new(|| Secp256k1::hash_to_F(b"forward"));
// Unfortunately, we have per-key offsets as it's the root key plus the base offset may not be
// even. While we could tweak the key until all derivations are even, that'd require significantly
// more tweaking. This algorithmic complexity is preferred.
pub(crate) fn offsets_for_key(
key: <Secp256k1 as Ciphersuite>::G,
) -> HashMap<OutputType, <Secp256k1 as Ciphersuite>::F> {
let mut offsets = HashMap::from([(OutputType::External, <Secp256k1 as Ciphersuite>::F::ZERO)]);
key: <Secp256k1 as WrappedGroup>::G,
) -> HashMap<OutputType, <Secp256k1 as WrappedGroup>::F> {
let mut offsets = HashMap::from([(OutputType::External, <Secp256k1 as WrappedGroup>::F::ZERO)]);
// We create an actual Bitcoin scanner as upon adding an offset, it yields the tweaked offset
// actually used
@@ -50,7 +50,7 @@ pub(crate) fn offsets_for_key(
offsets
}
pub(crate) fn scanner(key: <Secp256k1 as Ciphersuite>::G) -> Scanner {
pub(crate) fn scanner(key: <Secp256k1 as WrappedGroup>::G) -> Scanner {
let mut scanner = Scanner::new(key).unwrap();
for (_, offset) in offsets_for_key(key) {
let tweaked_offset = scanner.register_offset(offset).unwrap();

8
processor/bitcoin/src/scheduler.rs
View File

@@ -1,6 +1,6 @@
use core::future::Future;
use ciphersuite::Ciphersuite;
use ciphersuite::*;
use ciphersuite_kp256::Secp256k1;
use bitcoin_serai::{
@@ -26,8 +26,8 @@ use crate::{
rpc::Rpc,
};
fn address_from_serai_key(key: <Secp256k1 as Ciphersuite>::G, kind: OutputType) -> Address {
let offset = <Secp256k1 as Ciphersuite>::G::GENERATOR * offsets_for_key(key)[&kind];
fn address_from_serai_key(key: <Secp256k1 as WrappedGroup>::G, kind: OutputType) -> Address {
let offset = <Secp256k1 as WrappedGroup>::G::GENERATOR * offsets_for_key(key)[&kind];
Address::new(
p2tr_script_buf(key + offset)
.expect("creating address from Serai key which wasn't properly tweaked"),
@@ -72,7 +72,7 @@ fn signable_transaction<D: Db>(
*/
payments.push((
// The generator is even so this is valid
p2tr_script_buf(<Secp256k1 as Ciphersuite>::G::GENERATOR).unwrap(),
p2tr_script_buf(<Secp256k1 as WrappedGroup>::G::GENERATOR).unwrap(),
// This uses the minimum output value allowed, as defined as a constant in bitcoin-serai
// TODO: Add a test for this comparing to bitcoin's `minimal_non_dust`
bitcoin_serai::wallet::DUST,