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-rw-r--r--gcc-4.8.1/libgo/go/crypto/ecdsa/ecdsa.go155
1 files changed, 0 insertions, 155 deletions
diff --git a/gcc-4.8.1/libgo/go/crypto/ecdsa/ecdsa.go b/gcc-4.8.1/libgo/go/crypto/ecdsa/ecdsa.go
deleted file mode 100644
index 512d20c63..000000000
--- a/gcc-4.8.1/libgo/go/crypto/ecdsa/ecdsa.go
+++ /dev/null
@@ -1,155 +0,0 @@
-// Copyright 2011 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.
-
-// Package ecdsa implements the Elliptic Curve Digital Signature Algorithm, as
-// defined in FIPS 186-3.
-package ecdsa
-
-// References:
-// [NSA]: Suite B implementer's guide to FIPS 186-3,
-// http://www.nsa.gov/ia/_files/ecdsa.pdf
-// [SECG]: SECG, SEC1
-// http://www.secg.org/download/aid-780/sec1-v2.pdf
-
-import (
- "crypto/elliptic"
- "io"
- "math/big"
-)
-
-// PublicKey represents an ECDSA public key.
-type PublicKey struct {
- elliptic.Curve
- X, Y *big.Int
-}
-
-// PrivateKey represents a ECDSA private key.
-type PrivateKey struct {
- PublicKey
- D *big.Int
-}
-
-var one = new(big.Int).SetInt64(1)
-
-// randFieldElement returns a random element of the field underlying the given
-// curve using the procedure given in [NSA] A.2.1.
-func randFieldElement(c elliptic.Curve, rand io.Reader) (k *big.Int, err error) {
- params := c.Params()
- b := make([]byte, params.BitSize/8+8)
- _, err = io.ReadFull(rand, b)
- if err != nil {
- return
- }
-
- k = new(big.Int).SetBytes(b)
- n := new(big.Int).Sub(params.N, one)
- k.Mod(k, n)
- k.Add(k, one)
- return
-}
-
-// GenerateKey generates a public&private key pair.
-func GenerateKey(c elliptic.Curve, rand io.Reader) (priv *PrivateKey, err error) {
- k, err := randFieldElement(c, rand)
- if err != nil {
- return
- }
-
- priv = new(PrivateKey)
- priv.PublicKey.Curve = c
- priv.D = k
- priv.PublicKey.X, priv.PublicKey.Y = c.ScalarBaseMult(k.Bytes())
- return
-}
-
-// hashToInt converts a hash value to an integer. There is some disagreement
-// about how this is done. [NSA] suggests that this is done in the obvious
-// manner, but [SECG] truncates the hash to the bit-length of the curve order
-// first. We follow [SECG] because that's what OpenSSL does. Additionally,
-// OpenSSL right shifts excess bits from the number if the hash is too large
-// and we mirror that too.
-func hashToInt(hash []byte, c elliptic.Curve) *big.Int {
- orderBits := c.Params().N.BitLen()
- orderBytes := (orderBits + 7) / 8
- if len(hash) > orderBytes {
- hash = hash[:orderBytes]
- }
-
- ret := new(big.Int).SetBytes(hash)
- excess := len(hash)*8 - orderBits
- if excess > 0 {
- ret.Rsh(ret, uint(excess))
- }
- return ret
-}
-
-// Sign signs an arbitrary length hash (which should be the result of hashing a
-// larger message) using the private key, priv. It returns the signature as a
-// pair of integers. The security of the private key depends on the entropy of
-// rand.
-func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error) {
- // See [NSA] 3.4.1
- c := priv.PublicKey.Curve
- N := c.Params().N
-
- var k, kInv *big.Int
- for {
- for {
- k, err = randFieldElement(c, rand)
- if err != nil {
- r = nil
- return
- }
-
- kInv = new(big.Int).ModInverse(k, N)
- r, _ = priv.Curve.ScalarBaseMult(k.Bytes())
- r.Mod(r, N)
- if r.Sign() != 0 {
- break
- }
- }
-
- e := hashToInt(hash, c)
- s = new(big.Int).Mul(priv.D, r)
- s.Add(s, e)
- s.Mul(s, kInv)
- s.Mod(s, N)
- if s.Sign() != 0 {
- break
- }
- }
-
- return
-}
-
-// Verify verifies the signature in r, s of hash using the public key, pub. It
-// returns true iff the signature is valid.
-func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool {
- // See [NSA] 3.4.2
- c := pub.Curve
- N := c.Params().N
-
- if r.Sign() == 0 || s.Sign() == 0 {
- return false
- }
- if r.Cmp(N) >= 0 || s.Cmp(N) >= 0 {
- return false
- }
- e := hashToInt(hash, c)
- w := new(big.Int).ModInverse(s, N)
-
- u1 := e.Mul(e, w)
- u1.Mod(u1, N)
- u2 := w.Mul(r, w)
- u2.Mod(u2, N)
-
- x1, y1 := c.ScalarBaseMult(u1.Bytes())
- x2, y2 := c.ScalarMult(pub.X, pub.Y, u2.Bytes())
- x, y := c.Add(x1, y1, x2, y2)
- if x.Sign() == 0 && y.Sign() == 0 {
- return false
- }
- x.Mod(x, N)
- return x.Cmp(r) == 0
-}