1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package crypto
import (
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"encoding/hex"
"errors"
"io"
"io/ioutil"
"math/big"
"os"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto/sha3"
"github.com/ethereum/go-ethereum/rlp"
)
var (
secp256k1_N, _ = new(big.Int).SetString("fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141", 16)
secp256k1_halfN = new(big.Int).Div(secp256k1_N, big.NewInt(2))
)
func Keccak256(data ...[]byte) []byte {
d := sha3.NewKeccak256()
for _, b := range data {
d.Write(b)
}
return d.Sum(nil)
}
func Keccak256Hash(data ...[]byte) (h common.Hash) {
d := sha3.NewKeccak256()
for _, b := range data {
d.Write(b)
}
d.Sum(h[:0])
return h
}
// Deprecated: For backward compatibility as other packages depend on these
func Sha3Hash(data ...[]byte) common.Hash { return Keccak256Hash(data...) }
// Creates an ethereum address given the bytes and the nonce
func CreateAddress(b common.Address, nonce uint64) common.Address {
data, _ := rlp.EncodeToBytes([]interface{}{b, nonce})
return common.BytesToAddress(Keccak256(data)[12:])
}
// ToECDSA creates a private key with the given D value.
func ToECDSA(prv []byte) *ecdsa.PrivateKey {
if len(prv) == 0 {
return nil
}
priv := new(ecdsa.PrivateKey)
priv.PublicKey.Curve = S256()
priv.D = new(big.Int).SetBytes(prv)
priv.PublicKey.X, priv.PublicKey.Y = priv.PublicKey.Curve.ScalarBaseMult(prv)
return priv
}
func FromECDSA(prv *ecdsa.PrivateKey) []byte {
if prv == nil {
return nil
}
return prv.D.Bytes()
}
func ToECDSAPub(pub []byte) *ecdsa.PublicKey {
if len(pub) == 0 {
return nil
}
x, y := elliptic.Unmarshal(S256(), pub)
return &ecdsa.PublicKey{Curve: S256(), X: x, Y: y}
}
func FromECDSAPub(pub *ecdsa.PublicKey) []byte {
if pub == nil || pub.X == nil || pub.Y == nil {
return nil
}
return elliptic.Marshal(S256(), pub.X, pub.Y)
}
// HexToECDSA parses a secp256k1 private key.
func HexToECDSA(hexkey string) (*ecdsa.PrivateKey, error) {
b, err := hex.DecodeString(hexkey)
if err != nil {
return nil, errors.New("invalid hex string")
}
if len(b) != 32 {
return nil, errors.New("invalid length, need 256 bits")
}
return ToECDSA(b), nil
}
// LoadECDSA loads a secp256k1 private key from the given file.
// The key data is expected to be hex-encoded.
func LoadECDSA(file string) (*ecdsa.PrivateKey, error) {
buf := make([]byte, 64)
fd, err := os.Open(file)
if err != nil {
return nil, err
}
defer fd.Close()
if _, err := io.ReadFull(fd, buf); err != nil {
return nil, err
}
key, err := hex.DecodeString(string(buf))
if err != nil {
return nil, err
}
return ToECDSA(key), nil
}
// SaveECDSA saves a secp256k1 private key to the given file with
// restrictive permissions. The key data is saved hex-encoded.
func SaveECDSA(file string, key *ecdsa.PrivateKey) error {
k := hex.EncodeToString(FromECDSA(key))
return ioutil.WriteFile(file, []byte(k), 0600)
}
func GenerateKey() (*ecdsa.PrivateKey, error) {
return ecdsa.GenerateKey(S256(), rand.Reader)
}
// ValidateSignatureValues verifies whether the signature values are valid with
// the given chain rules. The v value is assumed to be either 0 or 1.
func ValidateSignatureValues(v byte, r, s *big.Int, homestead bool) bool {
if r.Cmp(common.Big1) < 0 || s.Cmp(common.Big1) < 0 {
return false
}
// reject upper range of s values (ECDSA malleability)
// see discussion in secp256k1/libsecp256k1/include/secp256k1.h
if homestead && s.Cmp(secp256k1_halfN) > 0 {
return false
}
// Frontier: allow s to be in full N range
return r.Cmp(secp256k1_N) < 0 && s.Cmp(secp256k1_N) < 0 && (v == 0 || v == 1)
}
func PubkeyToAddress(p ecdsa.PublicKey) common.Address {
pubBytes := FromECDSAPub(&p)
return common.BytesToAddress(Keccak256(pubBytes[1:])[12:])
}
func zeroBytes(bytes []byte) {
for i := range bytes {
bytes[i] = 0
}
}
|
