1 // Copyright (c) 2009-2012 The Bitcoin developers
2 // Distributed under the MIT/X11 software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
7 #include <openssl/ecdsa.h>
8 #include <openssl/evp.h>
9 #include <openssl/obj_mac.h>
14 // Generate a private key from just the secret parameter
15 int EC_KEY_regenerate_key(EC_KEY *eckey, BIGNUM *priv_key)
19 EC_POINT *pub_key = NULL;
23 const EC_GROUP *group = EC_KEY_get0_group(eckey);
25 if ((ctx = BN_CTX_new()) == NULL)
28 pub_key = EC_POINT_new(group);
33 if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx))
36 EC_KEY_set_private_key(eckey,priv_key);
37 EC_KEY_set_public_key(eckey,pub_key);
44 EC_POINT_free(pub_key);
51 // Perform ECDSA key recovery (see SEC1 4.1.6) for curves over (mod p)-fields
52 // recid selects which key is recovered
53 // if check is non-zero, additional checks are performed
54 int ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned char *msg, int msglen, int recid, int check)
75 const EC_GROUP *group = EC_KEY_get0_group(eckey);
76 if ((ctx = BN_CTX_new()) == NULL) { ret = -1; goto err; }
78 order = BN_CTX_get(ctx);
79 if (!EC_GROUP_get_order(group, order, ctx)) { ret = -2; goto err; }
81 if (!BN_copy(x, order)) { ret=-1; goto err; }
82 if (!BN_mul_word(x, i)) { ret=-1; goto err; }
83 if (!BN_add(x, x, ecsig->r)) { ret=-1; goto err; }
84 field = BN_CTX_get(ctx);
85 if (!EC_GROUP_get_curve_GFp(group, field, NULL, NULL, ctx)) { ret=-2; goto err; }
86 if (BN_cmp(x, field) >= 0) { ret=0; goto err; }
87 if ((R = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
88 if (!EC_POINT_set_compressed_coordinates_GFp(group, R, x, recid % 2, ctx)) { ret=0; goto err; }
91 if ((O = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
92 if (!EC_POINT_mul(group, O, NULL, R, order, ctx)) { ret=-2; goto err; }
93 if (!EC_POINT_is_at_infinity(group, O)) { ret = 0; goto err; }
95 if ((Q = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
96 n = EC_GROUP_get_degree(group);
98 if (!BN_bin2bn(msg, msglen, e)) { ret=-1; goto err; }
99 if (8*msglen > n) BN_rshift(e, e, 8-(n & 7));
100 zero = BN_CTX_get(ctx);
101 if (!BN_zero(zero)) { ret=-1; goto err; }
102 if (!BN_mod_sub(e, zero, e, order, ctx)) { ret=-1; goto err; }
103 rr = BN_CTX_get(ctx);
104 if (!BN_mod_inverse(rr, ecsig->r, order, ctx)) { ret=-1; goto err; }
105 sor = BN_CTX_get(ctx);
106 if (!BN_mod_mul(sor, ecsig->s, rr, order, ctx)) { ret=-1; goto err; }
107 eor = BN_CTX_get(ctx);
108 if (!BN_mod_mul(eor, e, rr, order, ctx)) { ret=-1; goto err; }
109 if (!EC_POINT_mul(group, Q, eor, R, sor, ctx)) { ret=-2; goto err; }
110 if (!EC_KEY_set_public_key(eckey, Q)) { ret=-2; goto err; }
119 if (R != NULL) EC_POINT_free(R);
120 if (O != NULL) EC_POINT_free(O);
121 if (Q != NULL) EC_POINT_free(Q);
125 int CompareBigEndian(const unsigned char *c1, size_t c1len, const unsigned char *c2, size_t c2len) {
126 while (c1len > c2len) {
132 while (c2len > c1len) {
150 // Order of secp256k1's generator minus 1.
151 const unsigned char vchMaxModOrder[32] = {
152 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
153 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFE,
154 0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,
155 0xBF,0xD2,0x5E,0x8C,0xD0,0x36,0x41,0x40
158 // Half of the order of secp256k1's generator minus 1.
159 const unsigned char vchMaxModHalfOrder[32] = {
160 0x7F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
161 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
162 0x5D,0x57,0x6E,0x73,0x57,0xA4,0x50,0x1D,
163 0xDF,0xE9,0x2F,0x46,0x68,0x1B,0x20,0xA0
166 const unsigned char *vchZero = NULL;
168 void CKey::SetCompressedPubKey(bool fCompressed)
170 EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
178 pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
180 throw key_error("CKey::CKey() : EC_KEY_new_by_curve_name failed");
189 CKey::CKey(const CKey& b)
191 pkey = EC_KEY_dup(b.pkey);
193 throw key_error("CKey::CKey(const CKey&) : EC_KEY_dup failed");
197 CKey::CKey(const CSecret& b, bool fCompressed)
199 pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
201 throw key_error("CKey::CKey(const CKey&) : EC_KEY_dup failed");
202 SetSecret(b, fCompressed);
205 CKey& CKey::operator=(const CKey& b)
207 if (!EC_KEY_copy(pkey, b.pkey))
208 throw key_error("CKey::operator=(const CKey&) : EC_KEY_copy failed");
219 bool CKey::IsNull() const
224 bool CKey::IsCompressed() const
226 return (EC_KEY_get_conv_form(pkey) == POINT_CONVERSION_COMPRESSED);
229 bool CKey::CheckSignatureElement(const unsigned char *vch, int len, bool half) {
230 return CompareBigEndian(vch, len, vchZero, 0) > 0 &&
231 CompareBigEndian(vch, len, half ? vchMaxModHalfOrder : vchMaxModOrder, 32) <= 0;
234 bool CPubKey::ReserealizeSignature(std::vector<unsigned char>& vchSig)
239 unsigned char *pos = &vchSig[0];
240 ECDSA_SIG *sig = d2i_ECDSA_SIG(NULL, (const unsigned char **)&pos, vchSig.size());
245 int nSize = i2d_ECDSA_SIG(sig, NULL);
247 vchSig.resize(nSize); // grow or shrink as needed
250 i2d_ECDSA_SIG(sig, &pos);
260 void CKey::MakeNewKey(bool fCompressed)
262 if (!EC_KEY_generate_key(pkey))
263 throw key_error("CKey::MakeNewKey() : EC_KEY_generate_key failed");
264 SetCompressedPubKey(fCompressed);
268 bool CKey::SetPrivKey(const CPrivKey& vchPrivKey)
270 const unsigned char* pbegin = &vchPrivKey[0];
271 if (d2i_ECPrivateKey(&pkey, &pbegin, vchPrivKey.size()))
273 // In testing, d2i_ECPrivateKey can return true
274 // but fill in pkey with a key that fails
275 // EC_KEY_check_key, so:
276 if (EC_KEY_check_key(pkey))
282 // If vchPrivKey data is bad d2i_ECPrivateKey() can
283 // leave pkey in a state where calling EC_KEY_free()
284 // crashes. To avoid that, set pkey to NULL and
285 // leak the memory (a leak is better than a crash)
291 bool CKey::SetSecret(const CSecret& vchSecret, bool fCompressed)
294 pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
296 throw key_error("CKey::SetSecret() : EC_KEY_new_by_curve_name failed");
298 if (vchSecret.size() != 32)
299 throw key_error("CKey::SetSecret() : secret must be 32 bytes");
300 BIGNUM *bn = BN_bin2bn(&vchSecret[0],32,BN_new());
302 throw key_error("CKey::SetSecret() : BN_bin2bn failed");
303 if (!EC_KEY_regenerate_key(pkey,bn))
306 throw key_error("CKey::SetSecret() : EC_KEY_regenerate_key failed");
310 SetCompressedPubKey(fCompressed);
314 CSecret CKey::GetSecret(bool &fCompressed) const
318 const BIGNUM *bn = EC_KEY_get0_private_key(pkey);
319 int nBytes = BN_num_bytes(bn);
321 throw key_error("CKey::GetSecret() : EC_KEY_get0_private_key failed");
322 int n=BN_bn2bin(bn,&vchRet[32 - nBytes]);
324 throw key_error("CKey::GetSecret(): BN_bn2bin failed");
325 fCompressed = IsCompressed();
329 bool CKey::WritePEM(BIO *streamObj, const SecureString &strPassKey) const // dumppem 4KJLA99FyqMMhjjDe7KnRXK4sjtv9cCtNS /tmp/test.pem 123
331 EVP_PKEY *evpKey = EVP_PKEY_new();
332 if (!EVP_PKEY_assign_EC_KEY(evpKey, pkey))
333 return error("CKey::WritePEM() : Error initializing EVP_PKEY instance.");
334 if(!PEM_write_bio_PKCS8PrivateKey(streamObj, evpKey, EVP_aes_256_cbc(), (char *)&strPassKey[0], strPassKey.size(), NULL, NULL))
335 return error("CKey::WritePEM() : Error writing private key data to stream object");
340 CSecret CKey::GetSecret() const
343 return GetSecret(fCompressed);
346 CPrivKey CKey::GetPrivKey() const
348 int nSize = i2d_ECPrivateKey(pkey, NULL);
350 throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey failed");
351 CPrivKey vchPrivKey(nSize, 0);
352 unsigned char* pbegin = &vchPrivKey[0];
353 if (i2d_ECPrivateKey(pkey, &pbegin) != nSize)
354 throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey returned unexpected size");
358 CPubKey CKey::GetPubKey() const
360 int nSize = i2o_ECPublicKey(pkey, NULL);
362 throw key_error("CKey::GetPubKey() : i2o_ECPublicKey failed");
363 std::vector<unsigned char> vchPubKey(nSize, 0);
364 unsigned char* pbegin = &vchPubKey[0];
365 if (i2o_ECPublicKey(pkey, &pbegin) != nSize)
366 throw key_error("CKey::GetPubKey() : i2o_ECPublicKey returned unexpected size");
367 return CPubKey(vchPubKey);
370 bool CKey::Sign(uint256 hash, std::vector<unsigned char>& vchSig)
373 ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
376 const EC_GROUP *group = EC_KEY_get0_group(pkey);
377 CBigNum order, halforder;
378 EC_GROUP_get_order(group, &order, NULL);
379 BN_rshift1(&halforder, &order);
380 // enforce low S values, by negating the value (modulo the order) if above order/2.
381 if (BN_cmp(sig->s, &halforder) > 0) {
382 BN_sub(sig->s, &order, sig->s);
384 unsigned int nSize = ECDSA_size(pkey);
385 vchSig.resize(nSize); // Make sure it is big enough
386 unsigned char *pos = &vchSig[0];
387 nSize = i2d_ECDSA_SIG(sig, &pos);
389 vchSig.resize(nSize); // Shrink to fit actual size
390 // Testing our new signature
391 if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1) {
398 // create a compact signature (65 bytes), which allows reconstructing the used public key
399 // The format is one header byte, followed by two times 32 bytes for the serialized r and s values.
400 // The header byte: 0x1B = first key with even y, 0x1C = first key with odd y,
401 // 0x1D = second key with even y, 0x1E = second key with odd y
402 bool CKey::SignCompact(uint256 hash, std::vector<unsigned char>& vchSig)
405 ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
408 const EC_GROUP *group = EC_KEY_get0_group(pkey);
409 CBigNum order, halforder;
410 EC_GROUP_get_order(group, &order, NULL);
411 BN_rshift1(&halforder, &order);
412 // enforce low S values, by negating the value (modulo the order) if above order/2.
413 if (BN_cmp(sig->s, &halforder) > 0) {
414 BN_sub(sig->s, &order, sig->s);
418 int nBitsR = BN_num_bits(sig->r);
419 int nBitsS = BN_num_bits(sig->s);
420 bool fCompressedPubKey = IsCompressed();
421 if (nBitsR <= 256 && nBitsS <= 256)
424 for (int8_t i=0; i<4; i++)
428 keyRec.SetCompressedPubKey(fCompressedPubKey);
429 if (ECDSA_SIG_recover_key_GFp(keyRec.pkey, sig, (unsigned char*)&hash, sizeof(hash), i, 1) == 1)
430 if (keyRec.GetPubKey() == this->GetPubKey())
440 throw key_error("CKey::SignCompact() : unable to construct recoverable key");
443 vchSig[0] = nRecId+27+(fCompressedPubKey ? 4 : 0);
444 BN_bn2bin(sig->r,&vchSig[33-(nBitsR+7)/8]);
445 BN_bn2bin(sig->s,&vchSig[65-(nBitsS+7)/8]);
452 // reconstruct public key from a compact signature
453 // This is only slightly more CPU intensive than just verifying it.
454 // If this function succeeds, the recovered public key is guaranteed to be valid
455 // (the signature is a valid signature of the given data for that key)
456 bool CPubKey::SetCompactSignature(uint256 hash, const std::vector<unsigned char>& vchSig)
458 if (vchSig.size() != 65)
463 ECDSA_SIG *sig = ECDSA_SIG_new();
464 BN_bin2bn(&vchSig[1],32,sig->r);
465 BN_bin2bn(&vchSig[33],32,sig->s);
466 bool fSuccessful = false;
467 EC_KEY* pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
471 EC_KEY_set_conv_form(pkey, POINT_CONVERSION_COMPRESSED);
475 if (ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), nV - 27, 0) != 1)
477 int nSize = i2o_ECPublicKey(pkey, NULL);
480 std::vector<unsigned char> vchPubKey(nSize, 0);
481 unsigned char* pbegin = &vchPubKey[0];
482 if (i2o_ECPublicKey(pkey, &pbegin) != nSize)
484 Set(vchPubKey.begin(), vchPubKey.end());
485 fSuccessful = IsValid();
495 bool CPubKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig) const
497 if (vchSig.empty() || !IsValid())
500 const unsigned char* pbegin = &vbytes[0];
501 EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
502 if (!o2i_ECPublicKey(&pkey, &pbegin, size()))
503 return false; // Unable to parse public key
505 // New versions of OpenSSL will reject non-canonical DER signatures. de/re-serialize first.
506 unsigned char *norm_der = NULL;
507 ECDSA_SIG *norm_sig = ECDSA_SIG_new();
508 const unsigned char* sigptr = &vchSig[0];
510 if (d2i_ECDSA_SIG(&norm_sig, &sigptr, vchSig.size()) == NULL)
512 /* As of OpenSSL 1.0.0p d2i_ECDSA_SIG frees and nulls the pointer on
513 * error. But OpenSSL's own use of this function redundantly frees the
514 * result. As ECDSA_SIG_free(NULL) is a no-op, and in the absence of a
515 * clear contract for the function behaving the same way is more
518 ECDSA_SIG_free(norm_sig);
521 int derlen = i2d_ECDSA_SIG(norm_sig, &norm_der);
522 ECDSA_SIG_free(norm_sig);
526 // -1 = error, 0 = bad sig, 1 = good
527 bool ret = ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), norm_der, derlen, pkey) == 1;
528 OPENSSL_free(norm_der);
532 bool CPubKey::VerifyCompact(uint256 hash, const std::vector<unsigned char>& vchSig)
535 if (!key.SetCompactSignature(hash, vchSig))
545 if (!EC_KEY_check_key(pkey))
549 CSecret secret = GetSecret(fCompr);
551 key2.SetSecret(secret, fCompr);
553 return GetPubKey() == key2.GetPubKey();
563 group = EC_GROUP_new_by_curve_name(NID_secp256k1);
565 err = "EC_KEY_new_by_curve_name failed.";
569 point = EC_POINT_new(group);
571 err = "EC_POINT_new failed.";
577 err = "BN_CTX_new failed.";
584 if (group) EC_GROUP_free(group);
585 if (point) EC_POINT_free(point);
586 throw std::runtime_error(std::string("CPoint::CPoint() : - ") + err);
589 bool CPoint::operator!=(const CPoint &a)
591 if (EC_POINT_cmp(group, point, a.point, ctx) != 0)
597 if (point) EC_POINT_free(point);
598 if (group) EC_GROUP_free(group);
599 if (ctx) BN_CTX_free(ctx);
602 // Initialize from octets stream
603 bool CPoint::setBytes(const std::vector<unsigned char> &vchBytes)
605 if (!EC_POINT_oct2point(group, point, &vchBytes[0], vchBytes.size(), ctx)) {
611 // Initialize from octets stream
612 bool CPoint::setPubKey(const CPubKey &key)
614 std::vector<uint8_t> vchPubKey(key.begin(), key.end());
615 return setBytes(vchPubKey);
618 // Serialize to octets stream
619 bool CPoint::getBytes(std::vector<unsigned char> &vchBytes)
621 size_t nSize = EC_POINT_point2oct(group, point, POINT_CONVERSION_COMPRESSED, NULL, 0, ctx);
622 vchBytes.resize(nSize);
623 if (!(nSize == EC_POINT_point2oct(group, point, POINT_CONVERSION_COMPRESSED, &vchBytes[0], nSize, ctx))) {
629 // ECC multiplication by specified multiplier
630 bool CPoint::ECMUL(const CBigNum &bnMultiplier)
632 if (!EC_POINT_mul(group, point, NULL, point, &bnMultiplier, NULL)) {
633 printf("CPoint::ECMUL() : EC_POINT_mul failed");
641 bool CPoint::ECMULGEN(const CBigNum &bnMultiplier, const CPoint &qPoint)
643 if (!EC_POINT_mul(group, point, &bnMultiplier, qPoint.point, BN_value_one(), NULL)) {
644 printf("CPoint::ECMULGEN() : EC_POINT_mul failed.");
653 void CMalleablePubKey::GetVariant(CPubKey &R, CPubKey &vchPubKeyVariant)
655 EC_KEY *eckey = NULL;
656 eckey = EC_KEY_new_by_curve_name(NID_secp256k1);
658 throw key_error("CMalleablePubKey::GetVariant() : EC_KEY_new_by_curve_name failed");
661 // Use standard key generation function to get r and R values.
663 // r will be presented by private key;
664 // R is ECDSA public key which calculated as G*r
665 if (!EC_KEY_generate_key(eckey)) {
666 throw key_error("CMalleablePubKey::GetVariant() : EC_KEY_generate_key failed");
669 EC_KEY_set_conv_form(eckey, POINT_CONVERSION_COMPRESSED);
671 int nSize = i2o_ECPublicKey(eckey, NULL);
673 throw key_error("CMalleablePubKey::GetVariant() : i2o_ECPublicKey failed");
676 std::vector<unsigned char> vchPubKey(nSize, 0);
677 unsigned char* pbegin_R = &vchPubKey[0];
679 if (i2o_ECPublicKey(eckey, &pbegin_R) != nSize) {
680 throw key_error("CMalleablePubKey::GetVariant() : i2o_ECPublicKey returned unexpected size");
684 R = CPubKey(vchPubKey);
686 // OpenSSL BIGNUM representation of r value
688 bnr = *(CBigNum*) EC_KEY_get0_private_key(eckey);
692 if (!point.setPubKey(pubKeyL)) {
693 throw key_error("CMalleablePubKey::GetVariant() : Unable to decode L value");
699 std::vector<unsigned char> vchLr;
700 if (!point.getBytes(vchLr)) {
701 throw key_error("CMalleablePubKey::GetVariant() : Unable to convert Lr value");
704 // Calculate Hash(L*r) and then get a BIGNUM representation of hash value.
706 bnHash.setuint160(Hash160(vchLr));
709 pointH.setPubKey(pubKeyH);
712 // Calculate P = Hash(L*r)*G + H
713 P.ECMULGEN(bnHash, pointH);
715 if (P.IsInfinity()) {
716 throw key_error("CMalleablePubKey::GetVariant() : P is infinity");
719 std::vector<unsigned char> vchResult;
720 P.getBytes(vchResult);
722 vchPubKeyVariant = CPubKey(vchResult);
725 std::string CMalleablePubKey::ToString() const
727 CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
729 std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
731 return EncodeBase58Check(vch);
734 bool CMalleablePubKey::setvch(const std::vector<unsigned char> &vchPubKeyPair)
736 CDataStream ssKey(vchPubKeyPair, SER_NETWORK, PROTOCOL_VERSION);
742 std::vector<unsigned char> CMalleablePubKey::Raw() const
744 CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
746 std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
751 bool CMalleablePubKey::SetString(const std::string& strMalleablePubKey)
753 std::vector<unsigned char> vchTemp;
754 if (!DecodeBase58Check(strMalleablePubKey, vchTemp)) {
755 throw key_error("CMalleablePubKey::SetString() : Provided key data seems corrupted.");
757 if (vchTemp.size() != 68)
760 CDataStream ssKey(vchTemp, SER_NETWORK, PROTOCOL_VERSION);
766 bool CMalleablePubKey::operator==(const CMalleablePubKey &b)
768 return pubKeyL == b.pubKeyL && pubKeyH == b.pubKeyH;
774 void CMalleableKey::Reset()
780 void CMalleableKey::MakeNewKeys()
788 vchSecretL = keyL.GetSecret();
789 vchSecretH = keyH.GetSecret();
792 CMalleableKey::CMalleableKey()
797 CMalleableKey::CMalleableKey(const CMalleableKey &b)
799 SetSecrets(b.vchSecretL, b.vchSecretH);
802 CMalleableKey::CMalleableKey(const CSecret &L, const CSecret &H)
807 CMalleableKey::~CMalleableKey()
811 bool CMalleableKey::IsNull() const
813 return vchSecretL.size() != 32 || vchSecretH.size() != 32;
816 bool CMalleableKey::SetSecrets(const CSecret &pvchSecretL, const CSecret &pvchSecretH)
820 CKey keyL(pvchSecretL);
821 CKey keyH(pvchSecretH);
823 if (!keyL.IsValid() || !keyH.IsValid())
826 vchSecretL = pvchSecretL;
827 vchSecretH = pvchSecretH;
832 CMalleablePubKey CMalleableKey::GetMalleablePubKey() const
834 CKey L(vchSecretL), H(vchSecretH);
835 return CMalleablePubKey(L.GetPubKey(), H.GetPubKey());
839 bool CMalleableKey::CheckKeyVariant(const CPubKey &R, const CPubKey &vchPubKeyVariant) const
842 throw key_error("CMalleableKey::CheckKeyVariant() : Attempting to run on NULL key object.");
846 printf("CMalleableKey::CheckKeyVariant() : R is invalid");
850 if (!vchPubKeyVariant.IsValid()) {
851 printf("CMalleableKey::CheckKeyVariant() : public key variant is invalid");
856 if (!point_R.setPubKey(R)) {
857 printf("CMalleableKey::CheckKeyVariant() : Unable to decode R value");
862 CPubKey vchPubKeyH = H.GetPubKey();
865 if (!point_H.setPubKey(vchPubKeyH)) {
866 printf("CMalleableKey::CheckKeyVariant() : Unable to decode H value");
871 if (!point_P.setPubKey(vchPubKeyVariant)) {
872 printf("CMalleableKey::CheckKeyVariant() : Unable to decode P value");
876 // Infinity points are senseless
877 if (point_P.IsInfinity()) {
878 printf("CMalleableKey::CheckKeyVariant() : P is infinity");
883 bnl.setBytes(std::vector<unsigned char>(vchSecretL.begin(), vchSecretL.end()));
887 std::vector<unsigned char> vchRl;
888 if (!point_R.getBytes(vchRl)) {
889 printf("CMalleableKey::CheckKeyVariant() : Unable to convert Rl value");
893 // Calculate Hash(R*l)
895 bnHash.setuint160(Hash160(vchRl));
898 // Calculate Ps = Hash(L*r)*G + H
899 point_Ps.ECMULGEN(bnHash, point_H);
901 // Infinity points are senseless
902 if (point_Ps.IsInfinity()) {
903 printf("CMalleableKey::CheckKeyVariant() : Ps is infinity");
908 if (point_Ps != point_P) {
915 // Check ownership and restore private key
916 bool CMalleableKey::CheckKeyVariant(const CPubKey &R, const CPubKey &vchPubKeyVariant, CKey &privKeyVariant) const
919 throw key_error("CMalleableKey::CheckKeyVariant() : Attempting to run on NULL key object.");
923 printf("CMalleableKey::CheckKeyVariant() : R is invalid");
927 if (!vchPubKeyVariant.IsValid()) {
928 printf("CMalleableKey::CheckKeyVariant() : public key variant is invalid");
933 if (!point_R.setPubKey(R)) {
934 printf("CMalleableKey::CheckKeyVariant() : Unable to decode R value");
939 CPubKey vchPubKeyH = H.GetPubKey();
942 if (!point_H.setPubKey(vchPubKeyH)) {
943 printf("CMalleableKey::CheckKeyVariant() : Unable to decode H value");
948 if (!point_P.setPubKey(vchPubKeyVariant)) {
949 printf("CMalleableKey::CheckKeyVariant() : Unable to decode P value");
953 // Infinity points are senseless
954 if (point_P.IsInfinity()) {
955 printf("CMalleableKey::CheckKeyVariant() : P is infinity");
960 bnl.setBytes(std::vector<unsigned char>(vchSecretL.begin(), vchSecretL.end()));
964 std::vector<unsigned char> vchRl;
965 if (!point_R.getBytes(vchRl)) {
966 printf("CMalleableKey::CheckKeyVariant() : Unable to convert Rl value");
970 // Calculate Hash(R*l)
972 bnHash.setuint160(Hash160(vchRl));
975 // Calculate Ps = Hash(L*r)*G + H
976 point_Ps.ECMULGEN(bnHash, point_H);
978 // Infinity points are senseless
979 if (point_Ps.IsInfinity()) {
980 printf("CMalleableKey::CheckKeyVariant() : Ps is infinity");
985 if (point_Ps != point_P) {
989 // OpenSSL BIGNUM representation of the second private key from (l, h) pair
991 bnh.setBytes(std::vector<unsigned char>(vchSecretH.begin(), vchSecretH.end()));
993 // Calculate p = Hash(R*l) + h
994 CBigNum bnp = bnHash + bnh;
996 std::vector<unsigned char> vchp = bnp.getBytes();
997 privKeyVariant.SetSecret(CSecret(vchp.begin(), vchp.end()));
1002 std::string CMalleableKey::ToString() const
1004 CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
1006 std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
1008 return EncodeBase58Check(vch);
1011 std::vector<unsigned char> CMalleableKey::Raw() const
1013 CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
1015 std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
1020 bool CMalleableKey::SetString(const std::string& strMutableKey)
1022 std::vector<unsigned char> vchTemp;
1023 if (!DecodeBase58Check(strMutableKey, vchTemp)) {
1024 throw key_error("CMalleableKey::SetString() : Provided key data seems corrupted.");
1026 if (vchTemp.size() != 66)
1028 CDataStream ssKey(vchTemp, SER_NETWORK, PROTOCOL_VERSION);
1034 // CMalleableKeyView
1036 CMalleableKeyView::CMalleableKeyView(const std::string &strMalleableKey)
1038 SetString(strMalleableKey);
1041 CMalleableKeyView::CMalleableKeyView(const CMalleableKey &b)
1043 if (b.vchSecretL.size() != 32)
1044 throw key_error("CMalleableKeyView::CMalleableKeyView() : L size must be 32 bytes");
1046 if (b.vchSecretH.size() != 32)
1047 throw key_error("CMalleableKeyView::CMalleableKeyView() : H size must be 32 bytes");
1049 vchSecretL = b.vchSecretL;
1051 CKey H(b.vchSecretH);
1052 vchPubKeyH = H.GetPubKey();
1055 CMalleableKeyView::CMalleableKeyView(const CMalleableKeyView &b)
1057 vchSecretL = b.vchSecretL;
1058 vchPubKeyH = b.vchPubKeyH;
1061 CMalleableKeyView& CMalleableKeyView::operator=(const CMalleableKey &b)
1063 vchSecretL = b.vchSecretL;
1065 CKey H(b.vchSecretH);
1066 vchPubKeyH = H.GetPubKey();
1071 CMalleableKeyView::~CMalleableKeyView()
1075 CMalleablePubKey CMalleableKeyView::GetMalleablePubKey() const
1077 CKey keyL(vchSecretL);
1078 return CMalleablePubKey(keyL.GetPubKey(), vchPubKeyH);
1082 bool CMalleableKeyView::CheckKeyVariant(const CPubKey &R, const CPubKey &vchPubKeyVariant) const
1085 throw key_error("CMalleableKeyView::CheckKeyVariant() : Attempting to run on invalid view object.");
1089 printf("CMalleableKeyView::CheckKeyVariant() : R is invalid");
1093 if (!vchPubKeyVariant.IsValid()) {
1094 printf("CMalleableKeyView::CheckKeyVariant() : public key variant is invalid");
1099 if (!point_R.setPubKey(R)) {
1100 printf("CMalleableKeyView::CheckKeyVariant() : Unable to decode R value");
1105 if (!point_H.setPubKey(vchPubKeyH)) {
1106 printf("CMalleableKeyView::CheckKeyVariant() : Unable to decode H value");
1111 if (!point_P.setPubKey(vchPubKeyVariant)) {
1112 printf("CMalleableKeyView::CheckKeyVariant() : Unable to decode P value");
1116 // Infinity points are senseless
1117 if (point_P.IsInfinity()) {
1118 printf("CMalleableKeyView::CheckKeyVariant() : P is infinity");
1123 bnl.setBytes(std::vector<unsigned char>(vchSecretL.begin(), vchSecretL.end()));
1127 std::vector<unsigned char> vchRl;
1128 if (!point_R.getBytes(vchRl)) {
1129 printf("CMalleableKeyView::CheckKeyVariant() : Unable to convert Rl value");
1133 // Calculate Hash(R*l)
1135 bnHash.setuint160(Hash160(vchRl));
1138 // Calculate Ps = Hash(L*r)*G + H
1139 point_Ps.ECMULGEN(bnHash, point_H);
1141 // Infinity points are senseless
1142 if (point_Ps.IsInfinity()) {
1143 printf("CMalleableKeyView::CheckKeyVariant() : Ps is infinity");
1148 if (point_Ps != point_P) {
1155 std::string CMalleableKeyView::ToString() const
1157 CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
1159 std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
1161 return EncodeBase58Check(vch);
1164 bool CMalleableKeyView::SetString(const std::string& strMutableKey)
1166 std::vector<unsigned char> vchTemp;
1167 if (!DecodeBase58Check(strMutableKey, vchTemp)) {
1168 throw key_error("CMalleableKeyView::SetString() : Provided key data seems corrupted.");
1171 if (vchTemp.size() != 67)
1174 CDataStream ssKey(vchTemp, SER_NETWORK, PROTOCOL_VERSION);
1180 std::vector<unsigned char> CMalleableKeyView::Raw() const
1182 CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
1184 std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
1190 bool CMalleableKeyView::IsValid() const
1192 return vchSecretL.size() == 32 && GetMalleablePubKey().IsValid();
1195 //// Asymmetric encryption
1197 void CPubKey::EncryptData(const std::vector<unsigned char>& data, std::vector<unsigned char>& encrypted)
1200 char error[1024] = "Unknown error";
1201 cryptogram_t *cryptogram;
1203 const unsigned char* pbegin = &vbytes[0];
1204 EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
1205 if (!o2i_ECPublicKey(&pkey, &pbegin, size()))
1206 throw key_error("Unable to parse EC key");
1208 ctx = create_context(pkey);
1209 if (!EC_KEY_get0_public_key(ctx->user_key))
1210 throw key_error("Given EC key is not public key");
1212 cryptogram = ecies_encrypt(ctx, (unsigned char*)&data[0], data.size(), error);
1213 if (cryptogram == NULL) {
1216 throw key_error(std::string("Error in encryption: %s") + error);
1219 encrypted.resize(cryptogram_data_sum_length(cryptogram));
1220 unsigned char *key_data = cryptogram_key_data(cryptogram);
1221 memcpy(&encrypted[0], key_data, encrypted.size());
1222 cryptogram_free(cryptogram);
1226 void CKey::DecryptData(const std::vector<unsigned char>& encrypted, std::vector<unsigned char>& data)
1229 char error[1024] = "Unknown error";
1230 cryptogram_t *cryptogram;
1232 unsigned char *decrypted;
1234 ctx = create_context(pkey);
1235 if (!EC_KEY_get0_private_key(ctx->user_key))
1236 throw key_error("Given EC key is not private key");
1238 size_t key_length = ctx->stored_key_length;
1239 size_t mac_length = EVP_MD_size(ctx->md);
1240 cryptogram = cryptogram_alloc(key_length, mac_length, encrypted.size() - key_length - mac_length);
1242 memcpy(cryptogram_key_data(cryptogram), &encrypted[0], encrypted.size());
1244 decrypted = ecies_decrypt(ctx, cryptogram, &length, error);
1245 cryptogram_free(cryptogram);
1248 if (decrypted == NULL) {
1249 throw key_error(std::string("Error in decryption: %s") + error);
1252 data.resize(length);
1253 memcpy(&data[0], decrypted, length);