mirror of
https://github.com/serai-dex/serai.git
synced 2025-12-09 04:39:24 +00:00
Move embedwards25519 over to short-weierstrass
This commit is contained in:
Luke Parker
@@ -23,12 +23,14 @@ zeroize = { version = "^1.5", default-features = false, features = ["zeroize_der
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generic-array = { version = "1", default-features = false }
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prime-field = { path = "../../prime-field", default-features = false }
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short-weierstrass = { path = "../../short-weierstrass", default-features = false }
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curve25519-dalek = { version = "4", default-features = false, features = ["legacy_compatibility"] }
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dalek-ff-group = { path = "../../dalek-ff-group", version = "0.4", default-features = false }
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blake2 = { version = "0.10", default-features = false }
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ciphersuite = { path = "../../ciphersuite", version = "0.4", default-features = false }
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ec-divisors = { git = "https://github.com/monero-oxide/monero-oxide", rev = "59e3ae73b51c214afbc304efca8d748b3da62977", default-features = false }
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generalized-bulletproofs-ec-gadgets = { git = "https://github.com/monero-oxide/monero-oxide", rev = "59e3ae73b51c214afbc304efca8d748b3da62977", default-features = false }
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generalized-bulletproofs-ec-gadgets = { git = "https://github.com/monero-oxide/monero-oxide", rev = "a6f8797007e768488568b821435cf5006517a962", default-features = false, optional = true }
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[dev-dependencies]
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hex = "0.4"
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@@ -38,6 +40,6 @@ rand_core = { version = "0.6", features = ["std"] }
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ff-group-tests = { path = "../../ff-group-tests" }
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[features]
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alloc = ["std-shims", "zeroize/alloc", "prime-field/alloc", "ciphersuite/alloc"]
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std = ["std-shims/std", "zeroize/std", "prime-field/std", "blake2/std", "ciphersuite/std", "ec-divisors/std", "generalized-bulletproofs-ec-gadgets/std"]
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alloc = ["std-shims", "zeroize/alloc", "prime-field/alloc", "short-weierstrass/alloc", "curve25519-dalek/alloc", "ciphersuite/alloc", "generalized-bulletproofs-ec-gadgets"]
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std = ["alloc", "std-shims/std", "zeroize/std", "prime-field/std", "short-weierstrass/std", "blake2/std", "ciphersuite/std", "generalized-bulletproofs-ec-gadgets/std"]
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default = ["std"]
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@@ -7,12 +7,17 @@ use std_shims::prelude::*;
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#[cfg(any(feature = "alloc", feature = "std"))]
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use std_shims::io::{self, Read};
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use generic_array::typenum::{Sum, Diff, Quot, U, U1, U2};
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use prime_field::{subtle::Choice, zeroize::Zeroize};
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use ciphersuite::group::{
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ff::{PrimeField, FromUniformBytes},
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ff::{Field, PrimeField, FromUniformBytes},
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Group,
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};
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use curve25519_dalek::Scalar as DalekScalar;
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pub use dalek_ff_group::Scalar as FieldElement;
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use short_weierstrass::{ShortWeierstrass, Affine, Projective};
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prime_field::odd_prime_field!(
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Scalar,
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"0fffffffffffffffffffffffffffffffe53f4debb78ff96877063f0306eef96b",
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@@ -20,33 +25,52 @@ prime_field::odd_prime_field!(
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false
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);
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pub use dalek_ff_group::Scalar as FieldElement;
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#[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize)]
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pub struct Embedwards25519;
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mod point;
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pub use point::Point;
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#[allow(deprecated)] // No other way to construct arbitrary `FieldElement` at compile-time :/
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impl ShortWeierstrass for Embedwards25519 {
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type FieldElement = FieldElement;
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const A: FieldElement = FieldElement(DalekScalar::from_bits(hex_literal::hex!(
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"ead3f55c1a631258d69cf7a2def9de1400000000000000000000000000000010"
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)));
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const B: FieldElement = FieldElement(DalekScalar::from_bits(hex_literal::hex!(
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"5f07603a853f20370b682036210d463e64903a23ea669d07ca26cfc13f594209"
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)));
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const GENERATOR: Affine<Self> = Affine::from_xy_unchecked(
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FieldElement::ONE,
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FieldElement(DalekScalar::from_bits(hex_literal::hex!(
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"2e4118080a484a3dfbafe2199a0e36b7193581d676c0dadfa376b0265616020c"
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))),
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);
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type Scalar = Scalar;
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pub(crate) fn u8_from_bool(bit_ref: &mut bool) -> u8 {
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use core::hint::black_box;
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use prime_field::zeroize::Zeroize;
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type Repr = [u8; 32];
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// Use an all-zero encoding for the identity as `0` isn't the `x` coordinate of an on-curve point
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const IDENTITY: [u8; 32] = [0; 32];
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fn compress(x: Self::FieldElement, odd_y: Choice) -> Self::Repr {
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// The LE `x` coordinate, with if `y` is odd in the unused 256th bit
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let mut res = [0; 32];
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res.as_mut().copy_from_slice(x.to_repr().as_ref());
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res[31] |= odd_y.unwrap_u8() << 7;
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res
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}
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fn decode_compressed(bytes: &Self::Repr) -> (<Self::FieldElement as PrimeField>::Repr, Choice) {
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// Extract and clear the sign bit
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let mut bytes = *bytes;
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let odd_y = Choice::from(bytes[31] >> 7);
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bytes[31] &= u8::MAX >> 1;
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let bit_ref = black_box(bit_ref);
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// Copy from the point's representation to the field's
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let mut repr = <Self::FieldElement as PrimeField>::Repr::default();
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repr.as_mut().copy_from_slice(&bytes);
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let mut bit = black_box(*bit_ref);
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let res = black_box(u8::from(bit));
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bit.zeroize();
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debug_assert!((res | 1) == 1);
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bit_ref.zeroize();
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res
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(repr, odd_y)
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}
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}
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/// Ciphersuite for Embedwards25519.
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///
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/// hash_to_F is implemented with a naive concatenation of the dst and data, allowing transposition
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/// between the two. This means `dst: b"abc", data: b"def"`, will produce the same scalar as
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/// `dst: "abcdef", data: b""`. Please use carefully, not letting dsts be substrings of each other.
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#[derive(Clone, Copy, PartialEq, Eq, Debug, zeroize::Zeroize)]
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pub struct Embedwards25519;
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pub type Point = Projective<Embedwards25519>;
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impl ciphersuite::Ciphersuite for Embedwards25519 {
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type F = Scalar;
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type G = Point;
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@@ -58,6 +82,10 @@ impl ciphersuite::Ciphersuite for Embedwards25519 {
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Point::generator()
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}
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/// `hash_to_F` is implemented with a naive concatenation of the `dst` and `data`, allowing
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/// transposition between the two. This means `dst: b"abc", data: b"def"`, will produce the same
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/// scalar as `dst: "abcdef", data: b""`. Please use carefully, not letting `dst` valuess be
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/// substrings of each other.
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fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
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use blake2::Digest;
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<Scalar as FromUniformBytes<64>>::from_uniform_bytes(
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@@ -67,7 +95,7 @@ impl ciphersuite::Ciphersuite for Embedwards25519 {
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// We override the provided impl, which compares against the reserialization, because
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// we already require canonicity
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#[cfg(any(feature = "alloc", feature = "std"))]
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#[cfg(feature = "alloc")]
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#[allow(non_snake_case)]
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fn read_G<R: Read>(reader: &mut R) -> io::Result<Self::G> {
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use ciphersuite::group::GroupEncoding;
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@@ -81,9 +109,38 @@ impl ciphersuite::Ciphersuite for Embedwards25519 {
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}
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}
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impl generalized_bulletproofs_ec_gadgets::DiscreteLogParameters for Embedwards25519 {
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type ScalarBits = U<{ Scalar::NUM_BITS as usize }>;
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type XCoefficients = Quot<Sum<Self::ScalarBits, U1>, U2>;
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type XCoefficientsMinusOne = Diff<Self::XCoefficients, U1>;
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type YxCoefficients = Diff<Quot<Sum<Sum<Self::ScalarBits, U1>, U1>, U2>, U2>;
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#[cfg(feature = "alloc")]
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impl generalized_bulletproofs_ec_gadgets::DiscreteLogParameter for Embedwards25519 {
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type ScalarBits = generic_array::typenum::U<{ <Scalar as PrimeField>::NUM_BITS as usize }>;
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}
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#[test]
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fn test_curve() {
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ff_group_tests::group::test_prime_group_bits::<_, Point>(&mut rand_core::OsRng);
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}
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#[test]
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fn generator() {
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use ciphersuite::group::{Group, GroupEncoding};
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assert_eq!(
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Point::generator(),
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Point::from_bytes(&hex_literal::hex!(
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"0100000000000000000000000000000000000000000000000000000000000000"
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))
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.unwrap()
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);
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}
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#[test]
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fn zero_x_is_off_curve() {
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assert!(bool::from(
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Affine::<Embedwards25519>::decompress(FieldElement::ZERO, 1.into()).is_none()
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));
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}
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// Checks random won't infinitely loop
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#[test]
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fn random() {
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use ciphersuite::group::Group;
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Point::random(&mut rand_core::OsRng);
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}
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@@ -1,441 +0,0 @@
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use core::{
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ops::{DerefMut, Add, AddAssign, Neg, Sub, SubAssign, Mul, MulAssign},
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iter::Sum,
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};
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use prime_field::{
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subtle::{Choice, CtOption, ConstantTimeEq, ConditionallySelectable},
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zeroize::Zeroize,
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rand_core::RngCore,
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};
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use ciphersuite::group::{
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ff::{Field, PrimeField, PrimeFieldBits},
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Group, GroupEncoding,
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prime::PrimeGroup,
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};
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use crate::{u8_from_bool, Scalar, FieldElement};
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#[allow(non_snake_case)]
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fn B() -> FieldElement {
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FieldElement::from_repr(hex_literal::hex!(
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"5f07603a853f20370b682036210d463e64903a23ea669d07ca26cfc13f594209"
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))
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.unwrap()
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}
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fn recover_y(x: FieldElement) -> CtOption<FieldElement> {
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// x**3 - 3 * x + B
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((x.square() * x) - (x.double() + x) + B()).sqrt()
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}
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/// Point.
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#[derive(Clone, Copy, Debug)]
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#[repr(C)]
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pub struct Point {
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x: FieldElement, // / Z
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y: FieldElement, // / Z
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z: FieldElement,
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}
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impl Zeroize for Point {
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fn zeroize(&mut self) {
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self.x.zeroize();
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self.y.zeroize();
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self.z.zeroize();
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let identity = Self::identity();
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self.x = identity.x;
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self.y = identity.y;
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self.z = identity.z;
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}
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}
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impl ConstantTimeEq for Point {
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fn ct_eq(&self, other: &Self) -> Choice {
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let x1 = self.x * other.z;
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let x2 = other.x * self.z;
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let y1 = self.y * other.z;
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let y2 = other.y * self.z;
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// Both identity or equivalent over their denominators
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(self.z.is_zero() & other.z.is_zero()) | (x1.ct_eq(&x2) & y1.ct_eq(&y2))
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}
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}
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impl PartialEq for Point {
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fn eq(&self, other: &Point) -> bool {
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self.ct_eq(other).into()
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}
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}
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impl Eq for Point {}
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impl ConditionallySelectable for Point {
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fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self {
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Point {
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x: FieldElement::conditional_select(&a.x, &b.x, choice),
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y: FieldElement::conditional_select(&a.y, &b.y, choice),
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z: FieldElement::conditional_select(&a.z, &b.z, choice),
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}
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}
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}
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impl Add for Point {
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type Output = Point;
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#[allow(non_snake_case)]
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fn add(self, other: Self) -> Self {
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// add-2015-rcb
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let a = -FieldElement::from(3u64);
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let B = B();
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let b3 = B + B + B;
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let X1 = self.x;
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let Y1 = self.y;
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let Z1 = self.z;
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let X2 = other.x;
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let Y2 = other.y;
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let Z2 = other.z;
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let t0 = X1 * X2;
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let t1 = Y1 * Y2;
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let t2 = Z1 * Z2;
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let t3 = X1 + Y1;
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let t4 = X2 + Y2;
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let t3 = t3 * t4;
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let t4 = t0 + t1;
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let t3 = t3 - t4;
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let t4 = X1 + Z1;
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let t5 = X2 + Z2;
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let t4 = t4 * t5;
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let t5 = t0 + t2;
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let t4 = t4 - t5;
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let t5 = Y1 + Z1;
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let X3 = Y2 + Z2;
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let t5 = t5 * X3;
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let X3 = t1 + t2;
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let t5 = t5 - X3;
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let Z3 = a * t4;
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let X3 = b3 * t2;
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let Z3 = X3 + Z3;
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let X3 = t1 - Z3;
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let Z3 = t1 + Z3;
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let Y3 = X3 * Z3;
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let t1 = t0 + t0;
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let t1 = t1 + t0;
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let t2 = a * t2;
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let t4 = b3 * t4;
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let t1 = t1 + t2;
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let t2 = t0 - t2;
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let t2 = a * t2;
|
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let t4 = t4 + t2;
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let t0 = t1 * t4;
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let Y3 = Y3 + t0;
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let t0 = t5 * t4;
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let X3 = t3 * X3;
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let X3 = X3 - t0;
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let t0 = t3 * t1;
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let Z3 = t5 * Z3;
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let Z3 = Z3 + t0;
|
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Point { x: X3, y: Y3, z: Z3 }
|
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}
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}
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|
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impl AddAssign for Point {
|
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fn add_assign(&mut self, other: Point) {
|
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*self = *self + other;
|
||||
}
|
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}
|
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|
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impl Add<&Point> for Point {
|
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type Output = Point;
|
||||
fn add(self, other: &Point) -> Point {
|
||||
self + *other
|
||||
}
|
||||
}
|
||||
|
||||
impl AddAssign<&Point> for Point {
|
||||
fn add_assign(&mut self, other: &Point) {
|
||||
*self += *other;
|
||||
}
|
||||
}
|
||||
|
||||
impl Neg for Point {
|
||||
type Output = Point;
|
||||
fn neg(self) -> Self {
|
||||
Point { x: self.x, y: -self.y, z: self.z }
|
||||
}
|
||||
}
|
||||
|
||||
impl Sub for Point {
|
||||
type Output = Point;
|
||||
#[allow(clippy::suspicious_arithmetic_impl)]
|
||||
fn sub(self, other: Self) -> Self {
|
||||
self + other.neg()
|
||||
}
|
||||
}
|
||||
|
||||
impl SubAssign for Point {
|
||||
fn sub_assign(&mut self, other: Point) {
|
||||
*self = *self - other;
|
||||
}
|
||||
}
|
||||
|
||||
impl Sub<&Point> for Point {
|
||||
type Output = Point;
|
||||
fn sub(self, other: &Point) -> Point {
|
||||
self - *other
|
||||
}
|
||||
}
|
||||
|
||||
impl SubAssign<&Point> for Point {
|
||||
fn sub_assign(&mut self, other: &Point) {
|
||||
*self -= *other;
|
||||
}
|
||||
}
|
||||
|
||||
impl Group for Point {
|
||||
type Scalar = Scalar;
|
||||
fn random(mut rng: impl RngCore) -> Self {
|
||||
loop {
|
||||
let mut bytes = [0; 32];
|
||||
rng.fill_bytes(bytes.as_mut());
|
||||
let opt = Self::from_bytes(&bytes);
|
||||
if opt.is_some().into() {
|
||||
return opt.unwrap();
|
||||
}
|
||||
}
|
||||
}
|
||||
fn identity() -> Self {
|
||||
Point { x: FieldElement::ZERO, y: FieldElement::ONE, z: FieldElement::ZERO }
|
||||
}
|
||||
fn generator() -> Self {
|
||||
// Point with the lowest valid x-coordinate
|
||||
Point {
|
||||
x: FieldElement::from_repr(hex_literal::hex!(
|
||||
"0100000000000000000000000000000000000000000000000000000000000000"
|
||||
))
|
||||
.unwrap(),
|
||||
y: FieldElement::from_repr(hex_literal::hex!(
|
||||
"2e4118080a484a3dfbafe2199a0e36b7193581d676c0dadfa376b0265616020c"
|
||||
))
|
||||
.unwrap(),
|
||||
z: FieldElement::ONE,
|
||||
}
|
||||
}
|
||||
fn is_identity(&self) -> Choice {
|
||||
self.z.ct_eq(&FieldElement::ZERO)
|
||||
}
|
||||
#[allow(non_snake_case)]
|
||||
fn double(&self) -> Self {
|
||||
// dbl-2007-bl-2
|
||||
let X1 = self.x;
|
||||
let Y1 = self.y;
|
||||
let Z1 = self.z;
|
||||
|
||||
let w = (X1 - Z1) * (X1 + Z1);
|
||||
let w = w.double() + w;
|
||||
let s = (Y1 * Z1).double();
|
||||
let ss = s.square();
|
||||
let sss = s * ss;
|
||||
let R = Y1 * s;
|
||||
let RR = R.square();
|
||||
let B_ = (X1 * R).double();
|
||||
let h = w.square() - B_.double();
|
||||
let X3 = h * s;
|
||||
let Y3 = w * (B_ - h) - RR.double();
|
||||
let Z3 = sss;
|
||||
|
||||
let res = Self { x: X3, y: Y3, z: Z3 };
|
||||
// If self is identity, res will not be well-formed
|
||||
// Accordingly, we return self if self was the identity
|
||||
Self::conditional_select(&res, self, self.is_identity())
|
||||
}
|
||||
}
|
||||
|
||||
impl Sum<Point> for Point {
|
||||
fn sum<I: Iterator<Item = Point>>(iter: I) -> Point {
|
||||
let mut res = Self::identity();
|
||||
for i in iter {
|
||||
res += i;
|
||||
}
|
||||
res
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a> Sum<&'a Point> for Point {
|
||||
fn sum<I: Iterator<Item = &'a Point>>(iter: I) -> Point {
|
||||
Point::sum(iter.cloned())
|
||||
}
|
||||
}
|
||||
|
||||
impl Mul<Scalar> for Point {
|
||||
type Output = Point;
|
||||
fn mul(self, mut other: Scalar) -> Point {
|
||||
// Precompute the optimal amount that's a multiple of 2
|
||||
let mut table = [Point::identity(); 16];
|
||||
table[1] = self;
|
||||
for i in 2 .. 16 {
|
||||
table[i] = table[i - 1] + self;
|
||||
}
|
||||
|
||||
let mut res = Self::identity();
|
||||
let mut bits = 0;
|
||||
for (i, mut bit) in other.to_le_bits().iter_mut().rev().enumerate() {
|
||||
bits <<= 1;
|
||||
let mut bit = u8_from_bool(bit.deref_mut());
|
||||
bits |= bit;
|
||||
bit.zeroize();
|
||||
|
||||
if ((i + 1) % 4) == 0 {
|
||||
if i != 3 {
|
||||
for _ in 0 .. 4 {
|
||||
res = res.double();
|
||||
}
|
||||
}
|
||||
|
||||
let mut term = table[0];
|
||||
for (j, candidate) in table[1 ..].iter().enumerate() {
|
||||
let j = j + 1;
|
||||
term = Self::conditional_select(&term, candidate, usize::from(bits).ct_eq(&j));
|
||||
}
|
||||
res += term;
|
||||
bits = 0;
|
||||
}
|
||||
}
|
||||
other.zeroize();
|
||||
res
|
||||
}
|
||||
}
|
||||
|
||||
impl MulAssign<Scalar> for Point {
|
||||
fn mul_assign(&mut self, other: Scalar) {
|
||||
*self = *self * other;
|
||||
}
|
||||
}
|
||||
|
||||
impl Mul<&Scalar> for Point {
|
||||
type Output = Point;
|
||||
fn mul(self, other: &Scalar) -> Point {
|
||||
self * *other
|
||||
}
|
||||
}
|
||||
|
||||
impl MulAssign<&Scalar> for Point {
|
||||
fn mul_assign(&mut self, other: &Scalar) {
|
||||
*self *= *other;
|
||||
}
|
||||
}
|
||||
|
||||
impl GroupEncoding for Point {
|
||||
type Repr = [u8; 32];
|
||||
|
||||
fn from_bytes(bytes: &Self::Repr) -> CtOption<Self> {
|
||||
// Extract and clear the sign bit
|
||||
let mut bytes = *bytes;
|
||||
let sign = Choice::from(bytes[31] >> 7);
|
||||
bytes[31] &= u8::MAX >> 1;
|
||||
|
||||
// Parse x, recover y
|
||||
FieldElement::from_repr(bytes).and_then(|x| {
|
||||
let is_identity = x.is_zero();
|
||||
|
||||
let y = recover_y(x).map(|mut y| {
|
||||
y = <_>::conditional_select(&y, &-y, y.is_odd().ct_eq(&!sign));
|
||||
y
|
||||
});
|
||||
|
||||
// If this the identity, set y to 1
|
||||
let y =
|
||||
CtOption::conditional_select(&y, &CtOption::new(FieldElement::ONE, 1.into()), is_identity);
|
||||
// If this the identity, set y to 1 and z to 0 (instead of 1)
|
||||
let z = <_>::conditional_select(&FieldElement::ONE, &FieldElement::ZERO, is_identity);
|
||||
// Create the point if we have a y solution
|
||||
let point = y.map(|y| Point { x, y, z });
|
||||
|
||||
let not_negative_zero = !(is_identity & sign);
|
||||
// Only return the point if it isn't -0
|
||||
CtOption::conditional_select(
|
||||
&CtOption::new(Point::identity(), 0.into()),
|
||||
&point,
|
||||
not_negative_zero,
|
||||
)
|
||||
})
|
||||
}
|
||||
|
||||
fn from_bytes_unchecked(bytes: &Self::Repr) -> CtOption<Self> {
|
||||
Point::from_bytes(bytes)
|
||||
}
|
||||
|
||||
fn to_bytes(&self) -> Self::Repr {
|
||||
let Some(z) = Option::<FieldElement>::from(self.z.invert()) else {
|
||||
return [0; 32];
|
||||
};
|
||||
let x = self.x * z;
|
||||
let y = self.y * z;
|
||||
|
||||
let mut res = [0; 32];
|
||||
res.as_mut().copy_from_slice(&x.to_repr());
|
||||
|
||||
// The following conditional select normalizes the sign to 0 when x is 0
|
||||
let y_sign = u8::conditional_select(&y.is_odd().unwrap_u8(), &0, x.ct_eq(&FieldElement::ZERO));
|
||||
res[31] |= y_sign << 7;
|
||||
res
|
||||
}
|
||||
}
|
||||
|
||||
impl PrimeGroup for Point {}
|
||||
|
||||
impl ec_divisors::DivisorCurve for Point {
|
||||
type FieldElement = FieldElement;
|
||||
type XyPoint = ec_divisors::Projective<Self>;
|
||||
|
||||
fn interpolator_for_scalar_mul() -> &'static ec_divisors::Interpolator<Self::FieldElement> {
|
||||
static PRECOMPUTE: std_shims::sync::LazyLock<ec_divisors::Interpolator<FieldElement>> =
|
||||
std_shims::sync::LazyLock::new(|| {
|
||||
ec_divisors::Interpolator::new(usize::try_from(130).unwrap())
|
||||
});
|
||||
&PRECOMPUTE
|
||||
}
|
||||
|
||||
fn a() -> Self::FieldElement {
|
||||
-FieldElement::from(3u64)
|
||||
}
|
||||
fn b() -> Self::FieldElement {
|
||||
B()
|
||||
}
|
||||
|
||||
fn to_xy(point: Self) -> Option<(Self::FieldElement, Self::FieldElement)> {
|
||||
let z: Self::FieldElement = Option::from(point.z.invert())?;
|
||||
Some((point.x * z, point.y * z))
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn test_curve() {
|
||||
ff_group_tests::group::test_prime_group_bits::<_, Point>(&mut rand_core::OsRng);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn generator() {
|
||||
assert_eq!(
|
||||
Point::generator(),
|
||||
Point::from_bytes(&hex_literal::hex!(
|
||||
"0100000000000000000000000000000000000000000000000000000000000000"
|
||||
))
|
||||
.unwrap()
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn zero_x_is_invalid() {
|
||||
assert!(Option::<FieldElement>::from(recover_y(FieldElement::ZERO)).is_none());
|
||||
}
|
||||
|
||||
// Checks random won't infinitely loop
|
||||
#[test]
|
||||
fn random() {
|
||||
Point::random(&mut rand_core::OsRng);
|
||||
}
|
||||
@@ -23,8 +23,8 @@ prime-field = { path = "../../prime-field", default-features = false }
|
||||
|
||||
blake2 = { version = "0.10", default-features = false }
|
||||
ciphersuite = { path = "../../ciphersuite", version = "0.4", default-features = false }
|
||||
ec-divisors = { git = "https://github.com/monero-oxide/monero-oxide", rev = "59e3ae73b51c214afbc304efca8d748b3da62977", default-features = false }
|
||||
generalized-bulletproofs-ec-gadgets = { git = "https://github.com/monero-oxide/monero-oxide", rev = "59e3ae73b51c214afbc304efca8d748b3da62977", default-features = false }
|
||||
ec-divisors = { git = "https://github.com/monero-oxide/monero-oxide", rev = "a6f8797007e768488568b821435cf5006517a962", default-features = false }
|
||||
generalized-bulletproofs-ec-gadgets = { git = "https://github.com/monero-oxide/monero-oxide", rev = "a6f8797007e768488568b821435cf5006517a962", default-features = false }
|
||||
|
||||
[dev-dependencies]
|
||||
hex = "0.4"
|
||||
|
||||
@@ -9,7 +9,7 @@ use std_shims::io::{self, Read};
|
||||
|
||||
use k256::elliptic_curve::{
|
||||
zeroize::Zeroize,
|
||||
generic_array::typenum::{Sum, Diff, Quot, U, U1, U2},
|
||||
generic_array::typenum::U,
|
||||
group::{
|
||||
ff::{PrimeField, FromUniformBytes},
|
||||
Group,
|
||||
@@ -87,9 +87,6 @@ impl ciphersuite::Ciphersuite for Secq256k1 {
|
||||
}
|
||||
}
|
||||
|
||||
impl generalized_bulletproofs_ec_gadgets::DiscreteLogParameters for Secq256k1 {
|
||||
impl generalized_bulletproofs_ec_gadgets::DiscreteLogParameter for Secq256k1 {
|
||||
type ScalarBits = U<{ Scalar::NUM_BITS as usize }>;
|
||||
type XCoefficients = Quot<Sum<Self::ScalarBits, U1>, U2>;
|
||||
type XCoefficientsMinusOne = Diff<Self::XCoefficients, U1>;
|
||||
type YxCoefficients = Diff<Quot<Sum<Sum<Self::ScalarBits, U1>, U1>, U2>, U2>;
|
||||
}
|
||||
|
||||
@@ -1,4 +1,5 @@
|
||||
use core::{
|
||||
borrow::Borrow,
|
||||
ops::{DerefMut, Add, AddAssign, Neg, Sub, SubAssign, Mul, MulAssign},
|
||||
iter::Sum,
|
||||
};
|
||||
@@ -389,12 +390,12 @@ impl ec_divisors::DivisorCurve for Point {
|
||||
type FieldElement = FieldElement;
|
||||
type XyPoint = ec_divisors::Projective<Self>;
|
||||
|
||||
fn interpolator_for_scalar_mul() -> &'static ec_divisors::Interpolator<Self::FieldElement> {
|
||||
fn interpolator_for_scalar_mul() -> impl Borrow<ec_divisors::Interpolator<Self::FieldElement>> {
|
||||
static PRECOMPUTE: std_shims::sync::LazyLock<ec_divisors::Interpolator<FieldElement>> =
|
||||
std_shims::sync::LazyLock::new(|| {
|
||||
ec_divisors::Interpolator::new(usize::try_from(130).unwrap())
|
||||
});
|
||||
&PRECOMPUTE
|
||||
&*PRECOMPUTE
|
||||
}
|
||||
|
||||
fn a() -> Self::FieldElement {
|
||||
|
||||
Reference in New Issue
Block a user