forked from hyperledger-archives/aries-framework-go
-
Notifications
You must be signed in to change notification settings - Fork 0
/
ecdsa.go
157 lines (124 loc) · 4.21 KB
/
ecdsa.go
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
/*
Copyright SecureKey Technologies Inc. All Rights Reserved.
SPDX-License-Identifier: Apache-2.0
*/
package signer
import (
"crypto"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"errors"
"github.com/btcsuite/btcd/btcec"
)
// NewECDSAP256Signer creates a new ECDSA P256 signer with generated key.
func NewECDSAP256Signer() (*ECDSASigner, error) {
privKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
if err != nil {
return nil, err
}
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA256), nil
}
// GetECDSAP256Signer creates a new ECDSA P256 signer with passed ECDSA P256 private key.
func GetECDSAP256Signer(privKey *ecdsa.PrivateKey) *ECDSASigner {
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA256)
}
// NewECDSAP384Signer creates a new ECDSA P384 signer with generated key.
func NewECDSAP384Signer() (*ECDSASigner, error) {
privKey, err := ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
if err != nil {
return nil, err
}
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA384), nil
}
// GetECDSAP384Signer creates a new ECDSA P384 signer with passed ECDSA P384 private key.
func GetECDSAP384Signer(privKey *ecdsa.PrivateKey) *ECDSASigner {
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA384)
}
// NewECDSAP521Signer creates a new ECDSA P521 signer with generated key.
func NewECDSAP521Signer() (*ECDSASigner, error) {
privKey, err := ecdsa.GenerateKey(elliptic.P521(), rand.Reader)
if err != nil {
return nil, err
}
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA512), nil
}
// GetECDSAP521Signer creates a new ECDSA P521 signer with passed ECDSA P521 private key.
func GetECDSAP521Signer(privKey *ecdsa.PrivateKey) *ECDSASigner {
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA512)
}
// NewECDSASecp256k1Signer creates a new ECDSA Secp256k1 signer with generated key.
func NewECDSASecp256k1Signer() (*ECDSASigner, error) {
privKey, err := ecdsa.GenerateKey(btcec.S256(), rand.Reader)
if err != nil {
return nil, err
}
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA256), nil
}
// GetECDSASecp256k1Signer creates a new ECDSA Secp256k1 signer with passed ECDSA Secp256k1 private key.
func GetECDSASecp256k1Signer(privKey *ecdsa.PrivateKey) *ECDSASigner {
return newECDSASigner(privKey, &privKey.PublicKey, crypto.SHA256)
}
// NewECDSASigner creates a new ECDSA signer based on the input elliptic curve.
func NewECDSASigner(curve elliptic.Curve) (*ECDSASigner, error) {
switch curve {
case elliptic.P256():
return NewECDSAP256Signer()
case elliptic.P384():
return NewECDSAP384Signer()
case elliptic.P521():
return NewECDSAP521Signer()
case btcec.S256():
return NewECDSASecp256k1Signer()
default:
return nil, errors.New("unsupported curve")
}
}
// ECDSASigner makes ECDSA based signatures.
type ECDSASigner struct {
privateKey *ecdsa.PrivateKey
PubKey *ecdsa.PublicKey
pubKeyBytes []byte
hash crypto.Hash
}
func newECDSASigner(privKey *ecdsa.PrivateKey, pubKey *ecdsa.PublicKey, hash crypto.Hash) *ECDSASigner {
return &ECDSASigner{
privateKey: privKey,
PubKey: pubKey,
pubKeyBytes: elliptic.Marshal(pubKey.Curve, pubKey.X, pubKey.Y),
hash: hash,
}
}
// PublicKey returns a public key object (*ecdsa.PublicKey).
func (es *ECDSASigner) PublicKey() interface{} {
return es.PubKey
}
// PublicKeyBytes returns bytes of the public key.
func (es *ECDSASigner) PublicKeyBytes() []byte {
return es.pubKeyBytes
}
// Sign signs a message.
func (es *ECDSASigner) Sign(msg []byte) ([]byte, error) {
return signEcdsa(msg, es.privateKey, es.hash)
}
//nolint:gomnd
func signEcdsa(msg []byte, privateKey *ecdsa.PrivateKey, hash crypto.Hash) ([]byte, error) {
hasher := hash.New()
_, _ = hasher.Write(msg) //nolint:errcheck
hashed := hasher.Sum(nil)
r, s, err := ecdsa.Sign(rand.Reader, privateKey, hashed)
if err != nil {
return nil, err
}
curveBits := privateKey.Curve.Params().BitSize
keyBytes := curveBits / 8
if curveBits%8 > 0 {
keyBytes++
}
copyPadded := func(source []byte, size int) []byte {
dest := make([]byte, size)
copy(dest[size-len(source):], source)
return dest
}
return append(copyPadded(r.Bytes(), keyBytes), copyPadded(s.Bytes(), keyBytes)...), nil
}