diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/curve25519/curve25519_compat.go')
-rw-r--r-- | vendor/golang.org/x/crypto/curve25519/curve25519_compat.go | 105 |
1 files changed, 0 insertions, 105 deletions
diff --git a/vendor/golang.org/x/crypto/curve25519/curve25519_compat.go b/vendor/golang.org/x/crypto/curve25519/curve25519_compat.go deleted file mode 100644 index ba647e8d7..000000000 --- a/vendor/golang.org/x/crypto/curve25519/curve25519_compat.go +++ /dev/null @@ -1,105 +0,0 @@ -// Copyright 2019 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -//go:build !go1.20 - -package curve25519 - -import ( - "crypto/subtle" - "errors" - "strconv" - - "golang.org/x/crypto/curve25519/internal/field" -) - -func scalarMult(dst, scalar, point *[32]byte) { - var e [32]byte - - copy(e[:], scalar[:]) - e[0] &= 248 - e[31] &= 127 - e[31] |= 64 - - var x1, x2, z2, x3, z3, tmp0, tmp1 field.Element - x1.SetBytes(point[:]) - x2.One() - x3.Set(&x1) - z3.One() - - swap := 0 - for pos := 254; pos >= 0; pos-- { - b := e[pos/8] >> uint(pos&7) - b &= 1 - swap ^= int(b) - x2.Swap(&x3, swap) - z2.Swap(&z3, swap) - swap = int(b) - - tmp0.Subtract(&x3, &z3) - tmp1.Subtract(&x2, &z2) - x2.Add(&x2, &z2) - z2.Add(&x3, &z3) - z3.Multiply(&tmp0, &x2) - z2.Multiply(&z2, &tmp1) - tmp0.Square(&tmp1) - tmp1.Square(&x2) - x3.Add(&z3, &z2) - z2.Subtract(&z3, &z2) - x2.Multiply(&tmp1, &tmp0) - tmp1.Subtract(&tmp1, &tmp0) - z2.Square(&z2) - - z3.Mult32(&tmp1, 121666) - x3.Square(&x3) - tmp0.Add(&tmp0, &z3) - z3.Multiply(&x1, &z2) - z2.Multiply(&tmp1, &tmp0) - } - - x2.Swap(&x3, swap) - z2.Swap(&z3, swap) - - z2.Invert(&z2) - x2.Multiply(&x2, &z2) - copy(dst[:], x2.Bytes()) -} - -func scalarBaseMult(dst, scalar *[32]byte) { - checkBasepoint() - scalarMult(dst, scalar, &basePoint) -} - -func x25519(dst *[32]byte, scalar, point []byte) ([]byte, error) { - var in [32]byte - if l := len(scalar); l != 32 { - return nil, errors.New("bad scalar length: " + strconv.Itoa(l) + ", expected 32") - } - if l := len(point); l != 32 { - return nil, errors.New("bad point length: " + strconv.Itoa(l) + ", expected 32") - } - copy(in[:], scalar) - if &point[0] == &Basepoint[0] { - scalarBaseMult(dst, &in) - } else { - var base, zero [32]byte - copy(base[:], point) - scalarMult(dst, &in, &base) - if subtle.ConstantTimeCompare(dst[:], zero[:]) == 1 { - return nil, errors.New("bad input point: low order point") - } - } - return dst[:], nil -} - -func checkBasepoint() { - if subtle.ConstantTimeCompare(Basepoint, []byte{ - 0x09, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, - 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, - 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, - 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, - }) != 1 { - panic("curve25519: global Basepoint value was modified") - } -} |