Implement a FROST algorithm for Schnorrkel

This commit is contained in:
Luke Parker 2023-01-13 18:52:38 -05:00
parent 50a4f5938a
commit 8ef8b5ca6f
No known key found for this signature in database
6 changed files with 258 additions and 3 deletions

64
Cargo.lock generated
View file

@ -1387,6 +1387,19 @@ dependencies = [
"zeroize",
]
[[package]]
name = "curve25519-dalek-ng"
version = "4.1.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "1c359b7249347e46fb28804470d071c921156ad62b3eef5d34e2ba867533dec8"
dependencies = [
"byteorder",
"digest 0.9.0",
"rand_core 0.6.4",
"subtle-ng",
"zeroize",
]
[[package]]
name = "cxx"
version = "1.0.86"
@ -2601,6 +2614,19 @@ dependencies = [
"sp-api",
]
[[package]]
name = "frost-schnorrkel"
version = "0.1.0"
dependencies = [
"ciphersuite",
"group",
"modular-frost",
"rand_core 0.6.4",
"schnorr-signatures",
"schnorrkel 0.10.2",
"zeroize",
]
[[package]]
name = "fs2"
version = "0.4.3"
@ -7107,6 +7133,23 @@ dependencies = [
"zeroize",
]
[[package]]
name = "schnorrkel"
version = "0.10.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "844b7645371e6ecdf61ff246ba1958c29e802881a749ae3fb1993675d210d28d"
dependencies = [
"arrayref",
"arrayvec 0.7.2",
"curve25519-dalek-ng",
"merlin 3.0.0",
"rand_core 0.6.4",
"serde_bytes",
"sha2 0.9.9",
"subtle-ng",
"zeroize",
]
[[package]]
name = "scopeguard"
version = "1.1.0"
@ -7369,6 +7412,15 @@ dependencies = [
"serde_json",
]
[[package]]
name = "serde_bytes"
version = "0.11.8"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "718dc5fff5b36f99093fc49b280cfc96ce6fc824317783bff5a1fed0c7a64819"
dependencies = [
"serde",
]
[[package]]
name = "serde_derive"
version = "1.0.152"
@ -7752,7 +7804,7 @@ dependencies = [
"rand 0.7.3",
"regex",
"scale-info",
"schnorrkel",
"schnorrkel 0.9.1",
"secp256k1",
"secrecy",
"serde",
@ -7905,7 +7957,7 @@ dependencies = [
"merlin 2.0.1",
"parity-scale-codec",
"parking_lot 0.12.1",
"schnorrkel",
"schnorrkel 0.9.1",
"serde",
"sp-core",
"sp-externalities",
@ -8344,7 +8396,7 @@ checksum = "49eee6965196b32f882dd2ee85a92b1dbead41b04e53907f269de3b0dc04733c"
dependencies = [
"hmac 0.11.0",
"pbkdf2 0.8.0",
"schnorrkel",
"schnorrkel 0.9.1",
"sha2 0.9.9",
"zeroize",
]
@ -8414,6 +8466,12 @@ version = "2.4.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "6bdef32e8150c2a081110b42772ffe7d7c9032b606bc226c8260fd97e0976601"
[[package]]
name = "subtle-ng"
version = "2.5.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "734676eb262c623cec13c3155096e08d1f8f29adce39ba17948b18dad1e54142"
[[package]]
name = "svm-rs"
version = "0.2.18"

View file

@ -15,6 +15,7 @@ members = [
"crypto/dleq",
"crypto/dkg",
"crypto/frost",
"crypto/schnorrkel",
"coins/ethereum",
"coins/monero/generators",

View file

@ -0,0 +1,28 @@
[package]
name = "frost-schnorrkel"
version = "0.1.0"
description = "modular-frost Algorithm compatible with Schnorrkel"
license = "MIT"
repository = "https://github.com/serai-dex/serai/tree/develop/crypto/schnorrkel"
authors = ["Luke Parker <lukeparker5132@gmail.com>"]
keywords = ["frost", "multisig", "threshold", "schnorrkel"]
edition = "2021"
[package.metadata.docs.rs]
all-features = true
rustdoc-args = ["--cfg", "docsrs"]
[dependencies]
rand_core = "0.6"
zeroize = "1.5"
group = "0.12"
ciphersuite = { path = "../ciphersuite", version = "0.1", features = ["std", "ristretto"] }
schnorr = { package = "schnorr-signatures", path = "../schnorr", version = "0.2" }
frost = { path = "../frost", package = "modular-frost", version = "0.5", features = ["ristretto"] }
schnorrkel = "0.10"
[dev-dependencies]
frost = { path = "../frost", package = "modular-frost", version = "0.5", features = ["ristretto", "tests"] }

21
crypto/schnorrkel/LICENSE Normal file
View file

@ -0,0 +1,21 @@
MIT License
Copyright (c) 2023 Luke Parker
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

View file

@ -0,0 +1,133 @@
use std::io::{self, Read};
use rand_core::{RngCore, CryptoRng};
use zeroize::Zeroizing;
use group::{ff::PrimeField, GroupEncoding};
use ciphersuite::{Ciphersuite, Ristretto};
use schnorr::SchnorrSignature;
use frost::{
ThresholdKeys, ThresholdView, FrostError,
algorithm::{IetfTranscript, Hram, Algorithm, Schnorr},
};
use schnorrkel::{PublicKey, Signature, context::SigningTranscript, signing_context};
type RistrettoPoint = <Ristretto as Ciphersuite>::G;
type Scalar = <Ristretto as Ciphersuite>::F;
#[cfg(test)]
mod tests;
#[derive(Clone)]
struct SchnorrkelHram;
impl Hram<Ristretto> for SchnorrkelHram {
#[allow(non_snake_case)]
fn hram(R: &RistrettoPoint, A: &RistrettoPoint, m: &[u8]) -> Scalar {
let ctx_len =
usize::try_from(u32::from_le_bytes(m[0 .. 4].try_into().expect("malformed message")))
.unwrap();
let mut t = signing_context(&m[4 .. (4 + ctx_len)]).bytes(&m[(4 + ctx_len) ..]);
t.proto_name(b"Schnorr-sig");
let convert =
|point: &RistrettoPoint| PublicKey::from_bytes(&point.to_bytes()).unwrap().into_compressed();
t.commit_point(b"sign:pk", &convert(A));
t.commit_point(b"sign:R", &convert(R));
Scalar::from_repr(t.challenge_scalar(b"sign:c").to_bytes()).unwrap()
}
}
#[derive(Clone)]
pub struct Schnorrkel {
context: &'static [u8],
schnorr: Schnorr<Ristretto, SchnorrkelHram>,
msg: Option<Vec<u8>>,
}
impl Schnorrkel {
pub fn new(context: &'static [u8]) -> Schnorrkel {
Schnorrkel { context, schnorr: Schnorr::new(), msg: None }
}
}
impl Algorithm<Ristretto> for Schnorrkel {
type Transcript = IetfTranscript;
type Addendum = ();
type Signature = Signature;
fn transcript(&mut self) -> &mut Self::Transcript {
self.schnorr.transcript()
}
fn nonces(&self) -> Vec<Vec<<Ristretto as Ciphersuite>::G>> {
self.schnorr.nonces()
}
fn preprocess_addendum<R: RngCore + CryptoRng>(
&mut self,
_: &mut R,
_: &ThresholdKeys<Ristretto>,
) {
}
fn read_addendum<R: Read>(&self, _: &mut R) -> io::Result<Self::Addendum> {
Ok(())
}
fn process_addendum(
&mut self,
_: &ThresholdView<Ristretto>,
_: u16,
_: (),
) -> Result<(), FrostError> {
Ok(())
}
fn sign_share(
&mut self,
params: &ThresholdView<Ristretto>,
nonce_sums: &[Vec<<Ristretto as Ciphersuite>::G>],
nonces: Vec<Zeroizing<<Ristretto as Ciphersuite>::F>>,
msg: &[u8],
) -> <Ristretto as Ciphersuite>::F {
self.msg = Some(msg.to_vec());
self.schnorr.sign_share(
params,
nonce_sums,
nonces,
&[
&u32::try_from(self.context.len()).expect("context exceeded 2^32 bytes").to_le_bytes(),
self.context,
msg,
]
.concat(),
)
}
#[must_use]
fn verify(
&self,
group_key: <Ristretto as Ciphersuite>::G,
nonces: &[Vec<<Ristretto as Ciphersuite>::G>],
sum: <Ristretto as Ciphersuite>::F,
) -> Option<Self::Signature> {
let mut sig = (SchnorrSignature::<Ristretto> { R: nonces[0][0], s: sum }).serialize();
sig[63] |= 1 << 7;
Some(Signature::from_bytes(&sig).unwrap()).filter(|sig| {
PublicKey::from_bytes(&group_key.to_bytes())
.unwrap()
.verify(&mut signing_context(self.context).bytes(self.msg.as_ref().unwrap()), sig)
.is_ok()
})
}
fn verify_share(
&self,
verification_share: <Ristretto as Ciphersuite>::G,
nonces: &[Vec<<Ristretto as Ciphersuite>::G>],
share: <Ristretto as Ciphersuite>::F,
) -> Result<Vec<(<Ristretto as Ciphersuite>::F, <Ristretto as Ciphersuite>::G)>, ()> {
self.schnorr.verify_share(verification_share, nonces, share)
}
}

View file

@ -0,0 +1,14 @@
use rand_core::OsRng;
use frost::tests::{key_gen, algorithm_machines, sign};
use crate::Schnorrkel;
#[test]
fn test() {
let keys = key_gen(&mut OsRng);
const CONTEXT: &[u8] = b"FROST Schnorrkel Test";
let machines = algorithm_machines(&mut OsRng, Schnorrkel::new(CONTEXT), &keys);
const MSG: &[u8] = b"Hello, World!";
sign(&mut OsRng, Schnorrkel::new(CONTEXT), keys, machines, MSG);
}