aboutsummaryrefslogtreecommitdiff
path: root/src/crypto/crypto.go
blob: 10a1cd8403a08b81af9b3c0f38fee3efed6102b2 (plain)
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
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
// 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 crypto collects common cryptographic constants.
package crypto

import (
	"hash"
	"io"
	"strconv"
)

// Hash identifies a cryptographic hash function that is implemented in another
// package.
type Hash uint

// HashFunc simply returns the value of h so that Hash implements SignerOpts.
func (h Hash) HashFunc() Hash {
	return h
}

func (h Hash) String() string {
	switch h {
	case MD4:
		return "MD4"
	case MD5:
		return "MD5"
	case SHA1:
		return "SHA-1"
	case SHA224:
		return "SHA-224"
	case SHA256:
		return "SHA-256"
	case SHA384:
		return "SHA-384"
	case SHA512:
		return "SHA-512"
	case MD5SHA1:
		return "MD5+SHA1"
	case RIPEMD160:
		return "RIPEMD-160"
	case SHA3_224:
		return "SHA3-224"
	case SHA3_256:
		return "SHA3-256"
	case SHA3_384:
		return "SHA3-384"
	case SHA3_512:
		return "SHA3-512"
	case SHA512_224:
		return "SHA-512/224"
	case SHA512_256:
		return "SHA-512/256"
	case BLAKE2s_256:
		return "BLAKE2s-256"
	case BLAKE2b_256:
		return "BLAKE2b-256"
	case BLAKE2b_384:
		return "BLAKE2b-384"
	case BLAKE2b_512:
		return "BLAKE2b-512"
	default:
		return "unknown hash value " + strconv.Itoa(int(h))
	}
}

const (
	MD4         Hash = 1 + iota // import golang.org/x/crypto/md4
	MD5                         // import crypto/md5
	SHA1                        // import crypto/sha1
	SHA224                      // import crypto/sha256
	SHA256                      // import crypto/sha256
	SHA384                      // import crypto/sha512
	SHA512                      // import crypto/sha512
	MD5SHA1                     // no implementation; MD5+SHA1 used for TLS RSA
	RIPEMD160                   // import golang.org/x/crypto/ripemd160
	SHA3_224                    // import golang.org/x/crypto/sha3
	SHA3_256                    // import golang.org/x/crypto/sha3
	SHA3_384                    // import golang.org/x/crypto/sha3
	SHA3_512                    // import golang.org/x/crypto/sha3
	SHA512_224                  // import crypto/sha512
	SHA512_256                  // import crypto/sha512
	BLAKE2s_256                 // import golang.org/x/crypto/blake2s
	BLAKE2b_256                 // import golang.org/x/crypto/blake2b
	BLAKE2b_384                 // import golang.org/x/crypto/blake2b
	BLAKE2b_512                 // import golang.org/x/crypto/blake2b
	maxHash
)

var digestSizes = []uint8{
	MD4:         16,
	MD5:         16,
	SHA1:        20,
	SHA224:      28,
	SHA256:      32,
	SHA384:      48,
	SHA512:      64,
	SHA512_224:  28,
	SHA512_256:  32,
	SHA3_224:    28,
	SHA3_256:    32,
	SHA3_384:    48,
	SHA3_512:    64,
	MD5SHA1:     36,
	RIPEMD160:   20,
	BLAKE2s_256: 32,
	BLAKE2b_256: 32,
	BLAKE2b_384: 48,
	BLAKE2b_512: 64,
}

// Size returns the length, in bytes, of a digest resulting from the given hash
// function. It doesn't require that the hash function in question be linked
// into the program.
func (h Hash) Size() int {
	if h > 0 && h < maxHash {
		return int(digestSizes[h])
	}
	panic("crypto: Size of unknown hash function")
}

var hashes = make([]func() hash.Hash, maxHash)

// New returns a new hash.Hash calculating the given hash function. New panics
// if the hash function is not linked into the binary.
func (h Hash) New() hash.Hash {
	if h > 0 && h < maxHash {
		f := hashes[h]
		if f != nil {
			return f()
		}
	}
	panic("crypto: requested hash function #" + strconv.Itoa(int(h)) + " is unavailable")
}

// Available reports whether the given hash function is linked into the binary.
func (h Hash) Available() bool {
	return h < maxHash && hashes[h] != nil
}

// RegisterHash registers a function that returns a new instance of the given
// hash function. This is intended to be called from the init function in
// packages that implement hash functions.
func RegisterHash(h Hash, f func() hash.Hash) {
	if h >= maxHash {
		panic("crypto: RegisterHash of unknown hash function")
	}
	hashes[h] = f
}

// PublicKey represents a public key using an unspecified algorithm.
//
// Although this type is an empty interface for backwards compatibility reasons,
// all public key types in the standard library implement the following interface
//
//	interface{
//	    Equal(x crypto.PublicKey) bool
//	}
//
// which can be used for increased type safety within applications.
type PublicKey any

// PrivateKey represents a private key using an unspecified algorithm.
//
// Although this type is an empty interface for backwards compatibility reasons,
// all private key types in the standard library implement the following interface
//
//	interface{
//	    Public() crypto.PublicKey
//	    Equal(x crypto.PrivateKey) bool
//	}
//
// as well as purpose-specific interfaces such as Signer and Decrypter, which
// can be used for increased type safety within applications.
type PrivateKey any

// Signer is an interface for an opaque private key that can be used for
// signing operations. For example, an RSA key kept in a hardware module.
type Signer interface {
	// Public returns the public key corresponding to the opaque,
	// private key.
	Public() PublicKey

	// Sign signs digest with the private key, possibly using entropy from
	// rand. For an RSA key, the resulting signature should be either a
	// PKCS #1 v1.5 or PSS signature (as indicated by opts). For an (EC)DSA
	// key, it should be a DER-serialised, ASN.1 signature structure.
	//
	// Hash implements the SignerOpts interface and, in most cases, one can
	// simply pass in the hash function used as opts. Sign may also attempt
	// to type assert opts to other types in order to obtain algorithm
	// specific values. See the documentation in each package for details.
	//
	// Note that when a signature of a hash of a larger message is needed,
	// the caller is responsible for hashing the larger message and passing
	// the hash (as digest) and the hash function (as opts) to Sign.
	Sign(rand io.Reader, digest []byte, opts SignerOpts) (signature []byte, err error)
}

// SignerOpts contains options for signing with a Signer.
type SignerOpts interface {
	// HashFunc returns an identifier for the hash function used to produce
	// the message passed to Signer.Sign, or else zero to indicate that no
	// hashing was done.
	HashFunc() Hash
}

// Decrypter is an interface for an opaque private key that can be used for
// asymmetric decryption operations. An example would be an RSA key
// kept in a hardware module.
type Decrypter interface {
	// Public returns the public key corresponding to the opaque,
	// private key.
	Public() PublicKey

	// Decrypt decrypts msg. The opts argument should be appropriate for
	// the primitive used. See the documentation in each implementation for
	// details.
	Decrypt(rand io.Reader, msg []byte, opts DecrypterOpts) (plaintext []byte, err error)
}

type DecrypterOpts any