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Diffstat (limited to 'gcc-4.8.1/libgo/go/crypto/dsa/dsa.go')
-rw-r--r--gcc-4.8.1/libgo/go/crypto/dsa/dsa.go270
1 files changed, 0 insertions, 270 deletions
diff --git a/gcc-4.8.1/libgo/go/crypto/dsa/dsa.go b/gcc-4.8.1/libgo/go/crypto/dsa/dsa.go
deleted file mode 100644
index 05766a2f1..000000000
--- a/gcc-4.8.1/libgo/go/crypto/dsa/dsa.go
+++ /dev/null
@@ -1,270 +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 dsa implements the Digital Signature Algorithm, as defined in FIPS 186-3.
-package dsa
-
-import (
- "errors"
- "io"
- "math/big"
-)
-
-// Parameters represents the domain parameters for a key. These parameters can
-// be shared across many keys. The bit length of Q must be a multiple of 8.
-type Parameters struct {
- P, Q, G *big.Int
-}
-
-// PublicKey represents a DSA public key.
-type PublicKey struct {
- Parameters
- Y *big.Int
-}
-
-// PrivateKey represents a DSA private key.
-type PrivateKey struct {
- PublicKey
- X *big.Int
-}
-
-// ErrInvalidPublicKey results when a public key is not usable by this code.
-// FIPS is quite strict about the format of DSA keys, but other code may be
-// less so. Thus, when using keys which may have been generated by other code,
-// this error must be handled.
-var ErrInvalidPublicKey = errors.New("crypto/dsa: invalid public key")
-
-// ParameterSizes is a enumeration of the acceptable bit lengths of the primes
-// in a set of DSA parameters. See FIPS 186-3, section 4.2.
-type ParameterSizes int
-
-const (
- L1024N160 ParameterSizes = iota
- L2048N224
- L2048N256
- L3072N256
-)
-
-// numMRTests is the number of Miller-Rabin primality tests that we perform. We
-// pick the largest recommended number from table C.1 of FIPS 186-3.
-const numMRTests = 64
-
-// GenerateParameters puts a random, valid set of DSA parameters into params.
-// This function takes many seconds, even on fast machines.
-func GenerateParameters(params *Parameters, rand io.Reader, sizes ParameterSizes) (err error) {
- // This function doesn't follow FIPS 186-3 exactly in that it doesn't
- // use a verification seed to generate the primes. The verification
- // seed doesn't appear to be exported or used by other code and
- // omitting it makes the code cleaner.
-
- var L, N int
- switch sizes {
- case L1024N160:
- L = 1024
- N = 160
- case L2048N224:
- L = 2048
- N = 224
- case L2048N256:
- L = 2048
- N = 256
- case L3072N256:
- L = 3072
- N = 256
- default:
- return errors.New("crypto/dsa: invalid ParameterSizes")
- }
-
- qBytes := make([]byte, N/8)
- pBytes := make([]byte, L/8)
-
- q := new(big.Int)
- p := new(big.Int)
- rem := new(big.Int)
- one := new(big.Int)
- one.SetInt64(1)
-
-GeneratePrimes:
- for {
- _, err = io.ReadFull(rand, qBytes)
- if err != nil {
- return
- }
-
- qBytes[len(qBytes)-1] |= 1
- qBytes[0] |= 0x80
- q.SetBytes(qBytes)
-
- if !q.ProbablyPrime(numMRTests) {
- continue
- }
-
- for i := 0; i < 4*L; i++ {
- _, err = io.ReadFull(rand, pBytes)
- if err != nil {
- return
- }
-
- pBytes[len(pBytes)-1] |= 1
- pBytes[0] |= 0x80
-
- p.SetBytes(pBytes)
- rem.Mod(p, q)
- rem.Sub(rem, one)
- p.Sub(p, rem)
- if p.BitLen() < L {
- continue
- }
-
- if !p.ProbablyPrime(numMRTests) {
- continue
- }
-
- params.P = p
- params.Q = q
- break GeneratePrimes
- }
- }
-
- h := new(big.Int)
- h.SetInt64(2)
- g := new(big.Int)
-
- pm1 := new(big.Int).Sub(p, one)
- e := new(big.Int).Div(pm1, q)
-
- for {
- g.Exp(h, e, p)
- if g.Cmp(one) == 0 {
- h.Add(h, one)
- continue
- }
-
- params.G = g
- return
- }
-
- panic("unreachable")
-}
-
-// GenerateKey generates a public&private key pair. The Parameters of the
-// PrivateKey must already be valid (see GenerateParameters).
-func GenerateKey(priv *PrivateKey, rand io.Reader) error {
- if priv.P == nil || priv.Q == nil || priv.G == nil {
- return errors.New("crypto/dsa: parameters not set up before generating key")
- }
-
- x := new(big.Int)
- xBytes := make([]byte, priv.Q.BitLen()/8)
-
- for {
- _, err := io.ReadFull(rand, xBytes)
- if err != nil {
- return err
- }
- x.SetBytes(xBytes)
- if x.Sign() != 0 && x.Cmp(priv.Q) < 0 {
- break
- }
- }
-
- priv.X = x
- priv.Y = new(big.Int)
- priv.Y.Exp(priv.G, x, priv.P)
- return nil
-}
-
-// 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.
-//
-// Note that FIPS 186-3 section 4.6 specifies that the hash should be truncated
-// to the byte-length of the subgroup. This function does not perform that
-// truncation itself.
-func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error) {
- // FIPS 186-3, section 4.6
-
- n := priv.Q.BitLen()
- if n&7 != 0 {
- err = ErrInvalidPublicKey
- return
- }
- n >>= 3
-
- for {
- k := new(big.Int)
- buf := make([]byte, n)
- for {
- _, err = io.ReadFull(rand, buf)
- if err != nil {
- return
- }
- k.SetBytes(buf)
- if k.Sign() > 0 && k.Cmp(priv.Q) < 0 {
- break
- }
- }
-
- kInv := new(big.Int).ModInverse(k, priv.Q)
-
- r = new(big.Int).Exp(priv.G, k, priv.P)
- r.Mod(r, priv.Q)
-
- if r.Sign() == 0 {
- continue
- }
-
- z := k.SetBytes(hash)
-
- s = new(big.Int).Mul(priv.X, r)
- s.Add(s, z)
- s.Mod(s, priv.Q)
- s.Mul(s, kInv)
- s.Mod(s, priv.Q)
-
- if s.Sign() != 0 {
- break
- }
- }
-
- return
-}
-
-// Verify verifies the signature in r, s of hash using the public key, pub. It
-// reports whether the signature is valid.
-//
-// Note that FIPS 186-3 section 4.6 specifies that the hash should be truncated
-// to the byte-length of the subgroup. This function does not perform that
-// truncation itself.
-func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool {
- // FIPS 186-3, section 4.7
-
- if r.Sign() < 1 || r.Cmp(pub.Q) >= 0 {
- return false
- }
- if s.Sign() < 1 || s.Cmp(pub.Q) >= 0 {
- return false
- }
-
- w := new(big.Int).ModInverse(s, pub.Q)
-
- n := pub.Q.BitLen()
- if n&7 != 0 {
- return false
- }
- z := new(big.Int).SetBytes(hash)
-
- u1 := new(big.Int).Mul(z, w)
- u1.Mod(u1, pub.Q)
- u2 := w.Mul(r, w)
- u2.Mod(u2, pub.Q)
- v := u1.Exp(pub.G, u1, pub.P)
- u2.Exp(pub.Y, u2, pub.P)
- v.Mul(v, u2)
- v.Mod(v, pub.P)
- v.Mod(v, pub.Q)
-
- return v.Cmp(r) == 0
-}