diff options
Diffstat (limited to 'src/crypto/elliptic/p256.go')
| -rw-r--r-- | src/crypto/elliptic/p256.go | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/src/crypto/elliptic/p256.go b/src/crypto/elliptic/p256.go index 05a3311b29..bbf0087e66 100644 --- a/src/crypto/elliptic/p256.go +++ b/src/crypto/elliptic/p256.go @@ -17,7 +17,8 @@ type p256Curve struct { } var ( - p256 p256Curve + p256Params *CurveParams + // RInverse contains 1/R mod p - the inverse of the Montgomery constant // (2**257). p256RInverse *big.Int @@ -25,15 +26,18 @@ var ( func initP256() { // See FIPS 186-3, section D.2.3 - p256.CurveParams = &CurveParams{Name: "P-256"} - p256.P, _ = new(big.Int).SetString("115792089210356248762697446949407573530086143415290314195533631308867097853951", 10) - p256.N, _ = new(big.Int).SetString("115792089210356248762697446949407573529996955224135760342422259061068512044369", 10) - p256.B, _ = new(big.Int).SetString("5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b", 16) - p256.Gx, _ = new(big.Int).SetString("6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296", 16) - p256.Gy, _ = new(big.Int).SetString("4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5", 16) - p256.BitSize = 256 + p256Params = &CurveParams{Name: "P-256"} + p256Params.P, _ = new(big.Int).SetString("115792089210356248762697446949407573530086143415290314195533631308867097853951", 10) + p256Params.N, _ = new(big.Int).SetString("115792089210356248762697446949407573529996955224135760342422259061068512044369", 10) + p256Params.B, _ = new(big.Int).SetString("5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b", 16) + p256Params.Gx, _ = new(big.Int).SetString("6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296", 16) + p256Params.Gy, _ = new(big.Int).SetString("4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5", 16) + p256Params.BitSize = 256 p256RInverse, _ = new(big.Int).SetString("7fffffff00000001fffffffe8000000100000000ffffffff0000000180000000", 16) + + // Arch-specific initialization, i.e. let a platform dynamically pick a P256 implementation + initP256Arch() } func (curve p256Curve) Params() *CurveParams { @@ -47,8 +51,8 @@ func p256GetScalar(out *[32]byte, in []byte) { n := new(big.Int).SetBytes(in) var scalarBytes []byte - if n.Cmp(p256.N) >= 0 { - n.Mod(n, p256.N) + if n.Cmp(p256Params.N) >= 0 { + n.Mod(n, p256Params.N) scalarBytes = n.Bytes() } else { scalarBytes = in @@ -1143,7 +1147,7 @@ func p256ScalarMult(xOut, yOut, zOut, x, y *[p256Limbs]uint32, scalar *[32]uint8 // p256FromBig sets out = R*in. func p256FromBig(out *[p256Limbs]uint32, in *big.Int) { tmp := new(big.Int).Lsh(in, 257) - tmp.Mod(tmp, p256.P) + tmp.Mod(tmp, p256Params.P) for i := 0; i < p256Limbs; i++ { if bits := tmp.Bits(); len(bits) > 0 { @@ -1183,6 +1187,6 @@ func p256ToBig(in *[p256Limbs]uint32) *big.Int { } result.Mul(result, p256RInverse) - result.Mod(result, p256.P) + result.Mod(result, p256Params.P) return result } |