key.cpp raw
1 // Copyright (c) 2009-present The Bitcoin Core developers
2 // Copyright (c) 2017 The Zcash developers
3 // Distributed under the MIT software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5
6 #include <key.h>
7
8 #include <crypto/common.h>
9 #include <crypto/hmac_sha512.h>
10 #include <hash.h>
11 #include <random.h>
12
13 #include <secp256k1.h>
14 #include <secp256k1_ellswift.h>
15 #include <secp256k1_extrakeys.h>
16 #include <secp256k1_recovery.h>
17 #include <secp256k1_schnorrsig.h>
18
19 static secp256k1_context* secp256k1_context_sign = nullptr;
20
21 /** These functions are taken from the libsecp256k1 distribution and are very ugly. */
22
23 /**
24 * This parses a format loosely based on a DER encoding of the ECPrivateKey type from
25 * section C.4 of SEC 1 <https://www.secg.org/sec1-v2.pdf>, with the following caveats:
26 *
27 * * The octet-length of the SEQUENCE must be encoded as 1 or 2 octets. It is not
28 * required to be encoded as one octet if it is less than 256, as DER would require.
29 * * The octet-length of the SEQUENCE must not be greater than the remaining
30 * length of the key encoding, but need not match it (i.e. the encoding may contain
31 * junk after the encoded SEQUENCE).
32 * * The privateKey OCTET STRING is zero-filled on the left to 32 octets.
33 * * Anything after the encoding of the privateKey OCTET STRING is ignored, whether
34 * or not it is validly encoded DER.
35 *
36 * out32 must point to an output buffer of length at least 32 bytes.
37 */
38 int ec_seckey_import_der(const secp256k1_context* ctx, unsigned char *out32, const unsigned char *seckey, size_t seckeylen) {
39 const unsigned char *end = seckey + seckeylen;
40 memset(out32, 0, 32);
41 /* sequence header */
42 if (end - seckey < 1 || *seckey != 0x30u) {
43 return 0;
44 }
45 seckey++;
46 /* sequence length constructor */
47 if (end - seckey < 1 || !(*seckey & 0x80u)) {
48 return 0;
49 }
50 ptrdiff_t lenb = *seckey & ~0x80u; seckey++;
51 if (lenb < 1 || lenb > 2) {
52 return 0;
53 }
54 if (end - seckey < lenb) {
55 return 0;
56 }
57 /* sequence length */
58 ptrdiff_t len = seckey[lenb-1] | (lenb > 1 ? seckey[lenb-2] << 8 : 0u);
59 seckey += lenb;
60 if (end - seckey < len) {
61 return 0;
62 }
63 /* sequence element 0: version number (=1) */
64 if (end - seckey < 3 || seckey[0] != 0x02u || seckey[1] != 0x01u || seckey[2] != 0x01u) {
65 return 0;
66 }
67 seckey += 3;
68 /* sequence element 1: octet string, up to 32 bytes */
69 if (end - seckey < 2 || seckey[0] != 0x04u) {
70 return 0;
71 }
72 ptrdiff_t oslen = seckey[1];
73 seckey += 2;
74 if (oslen > 32 || end - seckey < oslen) {
75 return 0;
76 }
77 memcpy(out32 + (32 - oslen), seckey, oslen);
78 if (!secp256k1_ec_seckey_verify(ctx, out32)) {
79 memset(out32, 0, 32);
80 return 0;
81 }
82 return 1;
83 }
84
85 /**
86 * This serializes to a DER encoding of the ECPrivateKey type from section C.4 of SEC 1
87 * <https://www.secg.org/sec1-v2.pdf>. The optional parameters and publicKey fields are
88 * included.
89 *
90 * seckey must point to an output buffer of length at least CKey::SIZE bytes.
91 * seckeylen must initially be set to the size of the seckey buffer. Upon return it
92 * will be set to the number of bytes used in the buffer.
93 * key32 must point to a 32-byte raw private key.
94 */
95 int ec_seckey_export_der(const secp256k1_context *ctx, unsigned char *seckey, size_t *seckeylen, const unsigned char *key32, bool compressed) {
96 assert(*seckeylen >= CKey::SIZE);
97 secp256k1_pubkey pubkey;
98 size_t pubkeylen = 0;
99 if (!secp256k1_ec_pubkey_create(ctx, &pubkey, key32)) {
100 *seckeylen = 0;
101 return 0;
102 }
103 if (compressed) {
104 static const unsigned char begin[] = {
105 0x30,0x81,0xD3,0x02,0x01,0x01,0x04,0x20
106 };
107 static const unsigned char middle[] = {
108 0xA0,0x81,0x85,0x30,0x81,0x82,0x02,0x01,0x01,0x30,0x2C,0x06,0x07,0x2A,0x86,0x48,
109 0xCE,0x3D,0x01,0x01,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
110 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
111 0xFF,0xFF,0xFE,0xFF,0xFF,0xFC,0x2F,0x30,0x06,0x04,0x01,0x00,0x04,0x01,0x07,0x04,
112 0x21,0x02,0x79,0xBE,0x66,0x7E,0xF9,0xDC,0xBB,0xAC,0x55,0xA0,0x62,0x95,0xCE,0x87,
113 0x0B,0x07,0x02,0x9B,0xFC,0xDB,0x2D,0xCE,0x28,0xD9,0x59,0xF2,0x81,0x5B,0x16,0xF8,
114 0x17,0x98,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
115 0xFF,0xFF,0xFF,0xFF,0xFE,0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,0xBF,0xD2,0x5E,
116 0x8C,0xD0,0x36,0x41,0x41,0x02,0x01,0x01,0xA1,0x24,0x03,0x22,0x00
117 };
118 unsigned char *ptr = seckey;
119 memcpy(ptr, begin, sizeof(begin)); ptr += sizeof(begin);
120 memcpy(ptr, key32, 32); ptr += 32;
121 memcpy(ptr, middle, sizeof(middle)); ptr += sizeof(middle);
122 pubkeylen = CPubKey::COMPRESSED_SIZE;
123 secp256k1_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey, SECP256K1_EC_COMPRESSED);
124 ptr += pubkeylen;
125 *seckeylen = ptr - seckey;
126 assert(*seckeylen == CKey::COMPRESSED_SIZE);
127 } else {
128 static const unsigned char begin[] = {
129 0x30,0x82,0x01,0x13,0x02,0x01,0x01,0x04,0x20
130 };
131 static const unsigned char middle[] = {
132 0xA0,0x81,0xA5,0x30,0x81,0xA2,0x02,0x01,0x01,0x30,0x2C,0x06,0x07,0x2A,0x86,0x48,
133 0xCE,0x3D,0x01,0x01,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
134 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
135 0xFF,0xFF,0xFE,0xFF,0xFF,0xFC,0x2F,0x30,0x06,0x04,0x01,0x00,0x04,0x01,0x07,0x04,
136 0x41,0x04,0x79,0xBE,0x66,0x7E,0xF9,0xDC,0xBB,0xAC,0x55,0xA0,0x62,0x95,0xCE,0x87,
137 0x0B,0x07,0x02,0x9B,0xFC,0xDB,0x2D,0xCE,0x28,0xD9,0x59,0xF2,0x81,0x5B,0x16,0xF8,
138 0x17,0x98,0x48,0x3A,0xDA,0x77,0x26,0xA3,0xC4,0x65,0x5D,0xA4,0xFB,0xFC,0x0E,0x11,
139 0x08,0xA8,0xFD,0x17,0xB4,0x48,0xA6,0x85,0x54,0x19,0x9C,0x47,0xD0,0x8F,0xFB,0x10,
140 0xD4,0xB8,0x02,0x21,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
141 0xFF,0xFF,0xFF,0xFF,0xFE,0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,0xBF,0xD2,0x5E,
142 0x8C,0xD0,0x36,0x41,0x41,0x02,0x01,0x01,0xA1,0x44,0x03,0x42,0x00
143 };
144 unsigned char *ptr = seckey;
145 memcpy(ptr, begin, sizeof(begin)); ptr += sizeof(begin);
146 memcpy(ptr, key32, 32); ptr += 32;
147 memcpy(ptr, middle, sizeof(middle)); ptr += sizeof(middle);
148 pubkeylen = CPubKey::SIZE;
149 secp256k1_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey, SECP256K1_EC_UNCOMPRESSED);
150 ptr += pubkeylen;
151 *seckeylen = ptr - seckey;
152 assert(*seckeylen == CKey::SIZE);
153 }
154 return 1;
155 }
156
157 bool CKey::Check(const unsigned char *vch) {
158 return secp256k1_ec_seckey_verify(secp256k1_context_static, vch);
159 }
160
161 void CKey::MakeNewKey(bool fCompressedIn) {
162 MakeKeyData();
163 do {
164 GetStrongRandBytes(*keydata);
165 } while (!Check(keydata->data()));
166 fCompressed = fCompressedIn;
167 }
168
169 CPrivKey CKey::GetPrivKey() const {
170 assert(keydata);
171 CPrivKey seckey;
172 int ret;
173 size_t seckeylen;
174 seckey.resize(SIZE);
175 seckeylen = SIZE;
176 ret = ec_seckey_export_der(secp256k1_context_sign, seckey.data(), &seckeylen, UCharCast(begin()), fCompressed);
177 assert(ret);
178 seckey.resize(seckeylen);
179 return seckey;
180 }
181
182 CPubKey CKey::GetPubKey() const {
183 assert(keydata);
184 secp256k1_pubkey pubkey;
185 size_t clen = CPubKey::SIZE;
186 CPubKey result;
187 int ret = secp256k1_ec_pubkey_create(secp256k1_context_sign, &pubkey, UCharCast(begin()));
188 assert(ret);
189 secp256k1_ec_pubkey_serialize(secp256k1_context_static, (unsigned char*)result.begin(), &clen, &pubkey, fCompressed ? SECP256K1_EC_COMPRESSED : SECP256K1_EC_UNCOMPRESSED);
190 assert(result.size() == clen);
191 assert(result.IsValid());
192 return result;
193 }
194
195 // Check that the sig has a low R value and will be less than 71 bytes
196 bool SigHasLowR(const secp256k1_ecdsa_signature* sig)
197 {
198 unsigned char compact_sig[64];
199 secp256k1_ecdsa_signature_serialize_compact(secp256k1_context_static, compact_sig, sig);
200
201 // In DER serialization, all values are interpreted as big-endian, signed integers. The highest bit in the integer indicates
202 // its signed-ness; 0 is positive, 1 is negative. When the value is interpreted as a negative integer, it must be converted
203 // to a positive value by prepending a 0x00 byte so that the highest bit is 0. We can avoid this prepending by ensuring that
204 // our highest bit is always 0, and thus we must check that the first byte is less than 0x80.
205 return compact_sig[0] < 0x80;
206 }
207
208 bool CKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool grind, uint32_t test_case) const {
209 if (!keydata)
210 return false;
211 vchSig.resize(CPubKey::SIGNATURE_SIZE);
212 size_t nSigLen = CPubKey::SIGNATURE_SIZE;
213 unsigned char extra_entropy[32] = {0};
214 WriteLE32(extra_entropy, test_case);
215 secp256k1_ecdsa_signature sig;
216 uint32_t counter = 0;
217 int ret = secp256k1_ecdsa_sign(secp256k1_context_sign, &sig, hash.begin(), UCharCast(begin()), secp256k1_nonce_function_rfc6979, (!grind && test_case) ? extra_entropy : nullptr);
218
219 // Grind for low R
220 while (ret && !SigHasLowR(&sig) && grind) {
221 WriteLE32(extra_entropy, ++counter);
222 ret = secp256k1_ecdsa_sign(secp256k1_context_sign, &sig, hash.begin(), UCharCast(begin()), secp256k1_nonce_function_rfc6979, extra_entropy);
223 }
224 assert(ret);
225 secp256k1_ecdsa_signature_serialize_der(secp256k1_context_static, vchSig.data(), &nSigLen, &sig);
226 vchSig.resize(nSigLen);
227 // Additional verification step to prevent using a potentially corrupted signature
228 secp256k1_pubkey pk;
229 ret = secp256k1_ec_pubkey_create(secp256k1_context_sign, &pk, UCharCast(begin()));
230 assert(ret);
231 ret = secp256k1_ecdsa_verify(secp256k1_context_static, &sig, hash.begin(), &pk);
232 assert(ret);
233 return true;
234 }
235
236 bool CKey::VerifyPubKey(const CPubKey& pubkey) const {
237 if (pubkey.IsCompressed() != fCompressed) {
238 return false;
239 }
240 unsigned char rnd[8];
241 std::string str = "Bitcoin key verification\n";
242 GetRandBytes(rnd);
243 uint256 hash{Hash(str, rnd)};
244 std::vector<unsigned char> vchSig;
245 Sign(hash, vchSig);
246 return pubkey.Verify(hash, vchSig);
247 }
248
249 bool CKey::SignCompact(const uint256 &hash, std::vector<unsigned char>& vchSig) const {
250 if (!keydata)
251 return false;
252 vchSig.resize(CPubKey::COMPACT_SIGNATURE_SIZE);
253 int rec = -1;
254 secp256k1_ecdsa_recoverable_signature rsig;
255 int ret = secp256k1_ecdsa_sign_recoverable(secp256k1_context_sign, &rsig, hash.begin(), UCharCast(begin()), secp256k1_nonce_function_rfc6979, nullptr);
256 assert(ret);
257 ret = secp256k1_ecdsa_recoverable_signature_serialize_compact(secp256k1_context_static, &vchSig[1], &rec, &rsig);
258 assert(ret);
259 assert(rec != -1);
260 vchSig[0] = 27 + rec + (fCompressed ? 4 : 0);
261 // Additional verification step to prevent using a potentially corrupted signature
262 secp256k1_pubkey epk, rpk;
263 ret = secp256k1_ec_pubkey_create(secp256k1_context_sign, &epk, UCharCast(begin()));
264 assert(ret);
265 ret = secp256k1_ecdsa_recover(secp256k1_context_static, &rpk, &rsig, hash.begin());
266 assert(ret);
267 ret = secp256k1_ec_pubkey_cmp(secp256k1_context_static, &epk, &rpk);
268 assert(ret == 0);
269 return true;
270 }
271
272 bool CKey::SignSchnorr(const uint256& hash, std::span<unsigned char> sig, const uint256* merkle_root, const uint256& aux) const
273 {
274 KeyPair kp = ComputeKeyPair(merkle_root);
275 return kp.SignSchnorr(hash, sig, aux);
276 }
277
278 bool CKey::Load(const CPrivKey &seckey, const CPubKey &vchPubKey, bool fSkipCheck=false) {
279 MakeKeyData();
280 if (!ec_seckey_import_der(secp256k1_context_static, (unsigned char*)begin(), seckey.data(), seckey.size())) {
281 ClearKeyData();
282 return false;
283 }
284 fCompressed = vchPubKey.IsCompressed();
285
286 if (fSkipCheck)
287 return true;
288
289 return VerifyPubKey(vchPubKey);
290 }
291
292 bool CKey::Derive(CKey& keyChild, ChainCode &ccChild, unsigned int nChild, const ChainCode& cc) const {
293 assert(IsValid());
294 assert(IsCompressed());
295 std::vector<unsigned char, secure_allocator<unsigned char>> vout(64);
296 if ((nChild >> 31) == 0) {
297 CPubKey pubkey = GetPubKey();
298 assert(pubkey.size() == CPubKey::COMPRESSED_SIZE);
299 BIP32Hash(cc, nChild, *pubkey.begin(), pubkey.begin()+1, vout.data());
300 } else {
301 assert(size() == 32);
302 BIP32Hash(cc, nChild, 0, UCharCast(begin()), vout.data());
303 }
304 memcpy(ccChild.begin(), vout.data()+32, 32);
305 keyChild.Set(begin(), begin() + 32, true);
306 bool ret = secp256k1_ec_seckey_tweak_add(secp256k1_context_static, (unsigned char*)keyChild.begin(), vout.data());
307 if (!ret) keyChild.ClearKeyData();
308 return ret;
309 }
310
311 EllSwiftPubKey CKey::EllSwiftCreate(std::span<const std::byte> ent32) const
312 {
313 assert(keydata);
314 assert(ent32.size() == 32);
315 std::array<std::byte, EllSwiftPubKey::size()> encoded_pubkey;
316
317 auto success = secp256k1_ellswift_create(secp256k1_context_sign,
318 UCharCast(encoded_pubkey.data()),
319 keydata->data(),
320 UCharCast(ent32.data()));
321
322 // Should always succeed for valid keys (asserted above).
323 assert(success);
324 return {encoded_pubkey};
325 }
326
327 ECDHSecret CKey::ComputeBIP324ECDHSecret(const EllSwiftPubKey& their_ellswift, const EllSwiftPubKey& our_ellswift, bool initiating) const
328 {
329 assert(keydata);
330
331 ECDHSecret output;
332 // BIP324 uses the initiator as party A, and the responder as party B. Remap the inputs
333 // accordingly:
334 bool success = secp256k1_ellswift_xdh(secp256k1_context_static,
335 UCharCast(output.data()),
336 UCharCast(initiating ? our_ellswift.data() : their_ellswift.data()),
337 UCharCast(initiating ? their_ellswift.data() : our_ellswift.data()),
338 keydata->data(),
339 initiating ? 0 : 1,
340 secp256k1_ellswift_xdh_hash_function_bip324,
341 nullptr);
342 // Should always succeed for valid keys (assert above).
343 assert(success);
344 return output;
345 }
346
347 KeyPair CKey::ComputeKeyPair(const uint256* merkle_root) const
348 {
349 return KeyPair(*this, merkle_root);
350 }
351
352 CKey GenerateRandomKey(bool compressed) noexcept
353 {
354 CKey key;
355 key.MakeNewKey(/*fCompressed=*/compressed);
356 return key;
357 }
358
359 bool CExtKey::Derive(CExtKey &out, unsigned int _nChild) const {
360 if (nDepth == std::numeric_limits<unsigned char>::max()) return false;
361 out.nDepth = nDepth + 1;
362 CKeyID id = key.GetPubKey().GetID();
363 memcpy(out.vchFingerprint, &id, 4);
364 out.nChild = _nChild;
365 return key.Derive(out.key, out.chaincode, _nChild, chaincode);
366 }
367
368 void CExtKey::SetSeed(std::span<const std::byte> seed)
369 {
370 static const unsigned char hashkey[] = {'B','i','t','c','o','i','n',' ','s','e','e','d'};
371 std::vector<unsigned char, secure_allocator<unsigned char>> vout(64);
372 CHMAC_SHA512{hashkey, sizeof(hashkey)}.Write(UCharCast(seed.data()), seed.size()).Finalize(vout.data());
373 key.Set(vout.data(), vout.data() + 32, true);
374 memcpy(chaincode.begin(), vout.data() + 32, 32);
375 nDepth = 0;
376 nChild = 0;
377 memset(vchFingerprint, 0, sizeof(vchFingerprint));
378 }
379
380 CExtPubKey CExtKey::Neuter() const {
381 CExtPubKey ret;
382 ret.nDepth = nDepth;
383 memcpy(ret.vchFingerprint, vchFingerprint, 4);
384 ret.nChild = nChild;
385 ret.pubkey = key.GetPubKey();
386 ret.chaincode = chaincode;
387 return ret;
388 }
389
390 void CExtKey::Encode(unsigned char code[BIP32_EXTKEY_SIZE]) const {
391 code[0] = nDepth;
392 memcpy(code+1, vchFingerprint, 4);
393 WriteBE32(code+5, nChild);
394 memcpy(code+9, chaincode.begin(), 32);
395 code[41] = 0;
396 assert(key.size() == 32);
397 memcpy(code+42, key.begin(), 32);
398 }
399
400 void CExtKey::Decode(const unsigned char code[BIP32_EXTKEY_SIZE]) {
401 nDepth = code[0];
402 memcpy(vchFingerprint, code+1, 4);
403 nChild = ReadBE32(code+5);
404 memcpy(chaincode.begin(), code+9, 32);
405 key.Set(code+42, code+BIP32_EXTKEY_SIZE, true);
406 if ((nDepth == 0 && (nChild != 0 || ReadLE32(vchFingerprint) != 0)) || code[41] != 0) key = CKey();
407 }
408
409 KeyPair::KeyPair(const CKey& key, const uint256* merkle_root)
410 {
411 static_assert(std::tuple_size<KeyType>() == sizeof(secp256k1_keypair));
412 MakeKeyPairData();
413 auto keypair = reinterpret_cast<secp256k1_keypair*>(m_keypair->data());
414 bool success = secp256k1_keypair_create(secp256k1_context_sign, keypair, UCharCast(key.data()));
415 if (success && merkle_root) {
416 secp256k1_xonly_pubkey pubkey;
417 unsigned char pubkey_bytes[32];
418 assert(secp256k1_keypair_xonly_pub(secp256k1_context_static, &pubkey, nullptr, keypair));
419 assert(secp256k1_xonly_pubkey_serialize(secp256k1_context_static, pubkey_bytes, &pubkey));
420 uint256 tweak = XOnlyPubKey(pubkey_bytes).ComputeTapTweakHash(merkle_root->IsNull() ? nullptr : merkle_root);
421 success = secp256k1_keypair_xonly_tweak_add(secp256k1_context_static, keypair, tweak.data());
422 }
423 if (!success) ClearKeyPairData();
424 }
425
426 bool KeyPair::SignSchnorr(const uint256& hash, std::span<unsigned char> sig, const uint256& aux) const
427 {
428 assert(sig.size() == 64);
429 if (!IsValid()) return false;
430 auto keypair = reinterpret_cast<const secp256k1_keypair*>(m_keypair->data());
431 bool ret = secp256k1_schnorrsig_sign32(secp256k1_context_sign, sig.data(), hash.data(), keypair, aux.data());
432 if (ret) {
433 // Additional verification step to prevent using a potentially corrupted signature
434 secp256k1_xonly_pubkey pubkey_verify;
435 ret = secp256k1_keypair_xonly_pub(secp256k1_context_static, &pubkey_verify, nullptr, keypair);
436 ret &= secp256k1_schnorrsig_verify(secp256k1_context_static, sig.data(), hash.begin(), 32, &pubkey_verify);
437 }
438 if (!ret) memory_cleanse(sig.data(), sig.size());
439 return ret;
440 }
441
442 bool ECC_InitSanityCheck() {
443 CKey key = GenerateRandomKey();
444 CPubKey pubkey = key.GetPubKey();
445 return key.VerifyPubKey(pubkey);
446 }
447
448 secp256k1_context* GetSecp256k1SignContext()
449 {
450 return secp256k1_context_sign;
451 }
452
453 /** Initialize the elliptic curve support. May not be called twice without calling ECC_Stop first. */
454 static void ECC_Start() {
455 assert(secp256k1_context_sign == nullptr);
456
457 secp256k1_context *ctx = secp256k1_context_create(SECP256K1_CONTEXT_NONE);
458 assert(ctx != nullptr);
459
460 {
461 // Pass in a random blinding seed to the secp256k1 context.
462 std::vector<unsigned char, secure_allocator<unsigned char>> vseed(32);
463 GetRandBytes(vseed);
464 bool ret = secp256k1_context_randomize(ctx, vseed.data());
465 assert(ret);
466 }
467
468 secp256k1_context_sign = ctx;
469 }
470
471 /** Deinitialize the elliptic curve support. No-op if ECC_Start wasn't called first. */
472 static void ECC_Stop() {
473 secp256k1_context *ctx = secp256k1_context_sign;
474 secp256k1_context_sign = nullptr;
475
476 if (ctx) {
477 secp256k1_context_destroy(ctx);
478 }
479 }
480
481 ECC_Context::ECC_Context()
482 {
483 ECC_Start();
484 }
485
486 ECC_Context::~ECC_Context()
487 {
488 ECC_Stop();
489 }
490