aboutsummaryrefslogtreecommitdiff
path: root/src/key.cpp
blob: 2369aa252121cf821b10e4b6cbd50c1a651e838b (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
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
// Copyright (c) 2009-2014 The Bitcoin developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include "key.h"

#include "crypto/sha2.h"
#include "eccryptoverify.h"
#include "random.h"

#ifdef USE_SECP256K1
#include <secp256k1.h>
#else
#include "ecwrapper.h"
#endif

//! anonymous namespace
namespace {

#ifdef USE_SECP256K1
#include <secp256k1.h>
class CSecp256k1Init {
public:
    CSecp256k1Init() {
        secp256k1_start();
    }
    ~CSecp256k1Init() {
        secp256k1_stop();
    }
};
static CSecp256k1Init instance_of_csecp256k1;

#endif
} // anon namespace

bool CKey::Check(const unsigned char *vch) {
    return eccrypto::Check(vch);
}

void CKey::MakeNewKey(bool fCompressedIn) {
    do {
        GetRandBytes(vch, sizeof(vch));
    } while (!Check(vch));
    fValid = true;
    fCompressed = fCompressedIn;
}

bool CKey::SetPrivKey(const CPrivKey &privkey, bool fCompressedIn) {
#ifdef USE_SECP256K1
    if (!secp256k1_ecdsa_privkey_import((unsigned char*)begin(), &privkey[0], privkey.size()))
        return false;
#else
    CECKey key;
    if (!key.SetPrivKey(&privkey[0], privkey.size()))
        return false;
    key.GetSecretBytes(vch);
#endif
    fCompressed = fCompressedIn;
    fValid = true;
    return true;
}

CPrivKey CKey::GetPrivKey() const {
    assert(fValid);
    CPrivKey privkey;
    int privkeylen, ret;
#ifdef USE_SECP256K1
    privkey.resize(279);
    privkeylen = 279;
    ret = secp256k1_ecdsa_privkey_export(begin(), (unsigned char*)&privkey[0], &privkeylen, fCompressed);
    assert(ret);
    privkey.resize(privkeylen);
#else
    CECKey key;
    key.SetSecretBytes(vch);
    privkeylen = key.GetPrivKeySize(fCompressed);
    assert(privkeylen);
    privkey.resize(privkeylen);
    ret = key.GetPrivKey(&privkey[0], fCompressed);
    assert(ret == (int)privkey.size());
#endif
    return privkey;
}

CPubKey CKey::GetPubKey() const {
    assert(fValid);
    CPubKey result;
#ifdef USE_SECP256K1
    int clen = 65;
    int ret = secp256k1_ecdsa_pubkey_create((unsigned char*)result.begin(), &clen, begin(), fCompressed);
    assert((int)result.size() == clen);
    assert(ret);
#else
    std::vector<unsigned char> pubkey;
    CECKey key;
    key.SetSecretBytes(vch);
    key.GetPubKey(pubkey, fCompressed);
    result.Set(pubkey.begin(), pubkey.end());
#endif
    assert(result.IsValid());
    return result;
}

bool CKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool lowS) const {
    if (!fValid)
        return false;
#ifdef USE_SECP256K1
    vchSig.resize(72);
    int nSigLen = 72;
    CKey nonce;
    do {
        nonce.MakeNewKey(true);
        if (secp256k1_ecdsa_sign((const unsigned char*)&hash, 32, (unsigned char*)&vchSig[0], &nSigLen, begin(), nonce.begin()))
            break;
    } while(true);
    vchSig.resize(nSigLen);
    return true;
#else
    CECKey key;
    key.SetSecretBytes(vch);
    return key.Sign(hash, vchSig, lowS);
#endif
}

bool CKey::SignCompact(const uint256 &hash, std::vector<unsigned char>& vchSig) const {
    if (!fValid)
        return false;
    vchSig.resize(65);
    int rec = -1;
#ifdef USE_SECP256K1
    CKey nonce;
    do {
        nonce.MakeNewKey(true);
        if (secp256k1_ecdsa_sign_compact((const unsigned char*)&hash, 32, &vchSig[1], begin(), nonce.begin(), &rec))
            break;
    } while(true);
#else
    CECKey key;
    key.SetSecretBytes(vch);
    if (!key.SignCompact(hash, &vchSig[1], rec))
        return false;
#endif
    assert(rec != -1);
    vchSig[0] = 27 + rec + (fCompressed ? 4 : 0);
    return true;
}

bool CKey::Load(CPrivKey &privkey, CPubKey &vchPubKey, bool fSkipCheck=false) {
#ifdef USE_SECP256K1
    if (!secp256k1_ecdsa_privkey_import((unsigned char*)begin(), &privkey[0], privkey.size()))
        return false;
#else
    CECKey key;
    if (!key.SetPrivKey(&privkey[0], privkey.size(), fSkipCheck))
        return false;
    key.GetSecretBytes(vch);
#endif
    fCompressed = vchPubKey.IsCompressed();
    fValid = true;

    if (fSkipCheck)
        return true;

    if (GetPubKey() != vchPubKey)
        return false;

    return true;
}

bool CPubKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig) const {
    if (!IsValid())
        return false;
#ifdef USE_SECP256K1
    if (secp256k1_ecdsa_verify((const unsigned char*)&hash, 32, &vchSig[0], vchSig.size(), begin(), size()) != 1)
        return false;
#else
    CECKey key;
    if (!key.SetPubKey(begin(), size()))
        return false;
    if (!key.Verify(hash, vchSig))
        return false;
#endif
    return true;
}

bool CPubKey::RecoverCompact(const uint256 &hash, const std::vector<unsigned char>& vchSig) {
    if (vchSig.size() != 65)
        return false;
    int recid = (vchSig[0] - 27) & 3;
    bool fComp = ((vchSig[0] - 27) & 4) != 0;
#ifdef USE_SECP256K1
    int pubkeylen = 65;
    if (!secp256k1_ecdsa_recover_compact((const unsigned char*)&hash, 32, &vchSig[1], (unsigned char*)begin(), &pubkeylen, fComp, recid))
        return false;
    assert((int)size() == pubkeylen);
#else
    CECKey key;
    if (!key.Recover(hash, &vchSig[1], recid))
        return false;
    std::vector<unsigned char> pubkey;
    key.GetPubKey(pubkey, fComp);
    Set(pubkey.begin(), pubkey.end());
#endif
    return true;
}

bool CPubKey::IsFullyValid() const {
    if (!IsValid())
        return false;
#ifdef USE_SECP256K1
    if (!secp256k1_ecdsa_pubkey_verify(begin(), size()))
        return false;
#else
    CECKey key;
    if (!key.SetPubKey(begin(), size()))
        return false;
#endif
    return true;
}

bool CPubKey::Decompress() {
    if (!IsValid())
        return false;
#ifdef USE_SECP256K1
    int clen = size();
    int ret = secp256k1_ecdsa_pubkey_decompress((unsigned char*)begin(), &clen);
    assert(ret);
    assert(clen == (int)size());
#else
    CECKey key;
    if (!key.SetPubKey(begin(), size()))
        return false;
    std::vector<unsigned char> pubkey;
    key.GetPubKey(pubkey, false);
    Set(pubkey.begin(), pubkey.end());
#endif
    return true;
}

bool CKey::Derive(CKey& keyChild, unsigned char ccChild[32], unsigned int nChild, const unsigned char cc[32]) const {
    assert(IsValid());
    assert(IsCompressed());
    unsigned char out[64];
    LockObject(out);
    if ((nChild >> 31) == 0) {
        CPubKey pubkey = GetPubKey();
        assert(pubkey.begin() + 33 == pubkey.end());
        BIP32Hash(cc, nChild, *pubkey.begin(), pubkey.begin()+1, out);
    } else {
        assert(begin() + 32 == end());
        BIP32Hash(cc, nChild, 0, begin(), out);
    }
    memcpy(ccChild, out+32, 32);
#ifdef USE_SECP256K1
    memcpy((unsigned char*)keyChild.begin(), begin(), 32);
    bool ret = secp256k1_ecdsa_privkey_tweak_add((unsigned char*)keyChild.begin(), out);
#else
    bool ret = CECKey::TweakSecret((unsigned char*)keyChild.begin(), begin(), out);
#endif
    UnlockObject(out);
    keyChild.fCompressed = true;
    keyChild.fValid = ret;
    return ret;
}

bool CPubKey::Derive(CPubKey& pubkeyChild, unsigned char ccChild[32], unsigned int nChild, const unsigned char cc[32]) const {
    assert(IsValid());
    assert((nChild >> 31) == 0);
    assert(begin() + 33 == end());
    unsigned char out[64];
    BIP32Hash(cc, nChild, *begin(), begin()+1, out);
    memcpy(ccChild, out+32, 32);
#ifdef USE_SECP256K1
    pubkeyChild = *this;
    bool ret = secp256k1_ecdsa_pubkey_tweak_add((unsigned char*)pubkeyChild.begin(), pubkeyChild.size(), out);
#else
    CECKey key;
    bool ret = key.SetPubKey(begin(), size());
    ret &= key.TweakPublic(out);
    std::vector<unsigned char> pubkey;
    key.GetPubKey(pubkey, true);
    pubkeyChild.Set(pubkey.begin(), pubkey.end());
#endif
    return ret;
}

bool CExtKey::Derive(CExtKey &out, unsigned int nChild) const {
    out.nDepth = nDepth + 1;
    CKeyID id = key.GetPubKey().GetID();
    memcpy(&out.vchFingerprint[0], &id, 4);
    out.nChild = nChild;
    return key.Derive(out.key, out.vchChainCode, nChild, vchChainCode);
}

void CExtKey::SetMaster(const unsigned char *seed, unsigned int nSeedLen) {
    static const unsigned char hashkey[] = {'B','i','t','c','o','i','n',' ','s','e','e','d'};
    unsigned char out[64];
    LockObject(out);
    CHMAC_SHA512(hashkey, sizeof(hashkey)).Write(seed, nSeedLen).Finalize(out);
    key.Set(&out[0], &out[32], true);
    memcpy(vchChainCode, &out[32], 32);
    UnlockObject(out);
    nDepth = 0;
    nChild = 0;
    memset(vchFingerprint, 0, sizeof(vchFingerprint));
}

CExtPubKey CExtKey::Neuter() const {
    CExtPubKey ret;
    ret.nDepth = nDepth;
    memcpy(&ret.vchFingerprint[0], &vchFingerprint[0], 4);
    ret.nChild = nChild;
    ret.pubkey = key.GetPubKey();
    memcpy(&ret.vchChainCode[0], &vchChainCode[0], 32);
    return ret;
}

void CExtKey::Encode(unsigned char code[74]) const {
    code[0] = nDepth;
    memcpy(code+1, vchFingerprint, 4);
    code[5] = (nChild >> 24) & 0xFF; code[6] = (nChild >> 16) & 0xFF;
    code[7] = (nChild >>  8) & 0xFF; code[8] = (nChild >>  0) & 0xFF;
    memcpy(code+9, vchChainCode, 32);
    code[41] = 0;
    assert(key.size() == 32);
    memcpy(code+42, key.begin(), 32);
}

void CExtKey::Decode(const unsigned char code[74]) {
    nDepth = code[0];
    memcpy(vchFingerprint, code+1, 4);
    nChild = (code[5] << 24) | (code[6] << 16) | (code[7] << 8) | code[8];
    memcpy(vchChainCode, code+9, 32);
    key.Set(code+42, code+74, true);
}

void CExtPubKey::Encode(unsigned char code[74]) const {
    code[0] = nDepth;
    memcpy(code+1, vchFingerprint, 4);
    code[5] = (nChild >> 24) & 0xFF; code[6] = (nChild >> 16) & 0xFF;
    code[7] = (nChild >>  8) & 0xFF; code[8] = (nChild >>  0) & 0xFF;
    memcpy(code+9, vchChainCode, 32);
    assert(pubkey.size() == 33);
    memcpy(code+41, pubkey.begin(), 33);
}

void CExtPubKey::Decode(const unsigned char code[74]) {
    nDepth = code[0];
    memcpy(vchFingerprint, code+1, 4);
    nChild = (code[5] << 24) | (code[6] << 16) | (code[7] << 8) | code[8];
    memcpy(vchChainCode, code+9, 32);
    pubkey.Set(code+41, code+74);
}

bool CExtPubKey::Derive(CExtPubKey &out, unsigned int nChild) const {
    out.nDepth = nDepth + 1;
    CKeyID id = pubkey.GetID();
    memcpy(&out.vchFingerprint[0], &id, 4);
    out.nChild = nChild;
    return pubkey.Derive(out.pubkey, out.vchChainCode, nChild, vchChainCode);
}

bool ECC_InitSanityCheck() {
#ifdef USE_SECP256K1
    return true;
#else
    return CECKey::SanityCheck();
#endif
}