saymrwulf/curve25519-dalek-source
1
0
Fork 0
mirror of https://github.com/saymrwulf/curve25519-dalek-source.git synced 2026-09-04 20:24:10 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Remove MSQRT_M1 constant

Browse source
This commit is contained in:
Henry de Valence 2017-10-30 17:36:00 -07:00
parent bbbe4bf665
commit 8f68b7a3ed
3 changed files with 1 additions and 16 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
src/constants.rs
View file

@ -149,27 +149,22 @@ mod test {
}
#[test]
/// Test that SQRT_M1 and MSQRT_M1 are square roots of -1
/// Test that SQRT_M1 is a square root of -1
fn test_sqrt_minus_one() {
let minus_one = FieldElement::minus_one();
let sqrt_m1_sq = &constants::SQRT_M1 * &constants::SQRT_M1;
let msqrt_m1_sq = &constants::MSQRT_M1 * &constants::MSQRT_M1;
assert_eq!(minus_one, sqrt_m1_sq);
assert_eq!(minus_one, msqrt_m1_sq);
}
#[test]
fn test_sqrt_constants_sign() {
let one = FieldElement::one();
let minus_one = FieldElement::minus_one();
let (was_nonzero_square, invsqrt_m1) = minus_one.invsqrt();
assert_eq!(was_nonzero_square, 1u8);
let sign_test_sqrt = &invsqrt_m1 * &constants::SQRT_M1;
let sign_test_msqrt = &invsqrt_m1 * &constants::MSQRT_M1;
// XXX it seems we have flipped the sign relative to
// the invsqrt function?
assert_eq!(sign_test_sqrt, minus_one);
assert_eq!(sign_test_msqrt, one);
}
/// Test that d = -121665/121666

6
src/constants_32bit.rs
View file

@ -45,12 +45,6 @@ pub(crate) const SQRT_M1: FieldElement32 = FieldElement32([
-32595792, -7943725, 9377950, 3500415, 12389472,
-272473, -25146209, -2005654, 326686, 11406482, ]);
/// Precomputed value of the other square root of -1 (mod p),
/// i.e., `MSQRT_M1 = -SQRT_M1`.
pub(crate) const MSQRT_M1: FieldElement32 = FieldElement32([
32595792, 7943725, -9377950, -3500415, -12389472,
272473, 25146209, 2005654, -326686, -11406482, ]);
/// In Montgomery form y² = x³+Ax²+x, Curve25519 has A=486662.
pub(crate) const MONTGOMERY_A: FieldElement32 = FieldElement32([
486662, 0, 0, 0, 0, 0, 0, 0, 0, 0, ]);

4
src/constants_64bit.rs
View file

@ -38,10 +38,6 @@ pub(crate) const INVSQRT_A_MINUS_D: FieldElement64 = FieldElement64([
/// Precomputed value of one of the square roots of -1 (mod p)
pub(crate) const SQRT_M1: FieldElement64 = FieldElement64([1718705420411056, 234908883556509, 2233514472574048, 2117202627021982, 765476049583133]);
/// Precomputed value of the other square root of -1 (mod p),
/// i.e., `MSQRT_M1 = -SQRT_M1`.
pub(crate) const MSQRT_M1: FieldElement64 = FieldElement64([533094393274173, 2016890930128738, 18285341111199, 134597186663265, 1486323764102114]);
/// In Montgomery form y² = x³+Ax²+x, Curve25519 has A=486662.
pub(crate) const MONTGOMERY_A: FieldElement64 = FieldElement64([486662, 0, 0, 0, 0]);