diff --git a/src/key.cpp b/src/key.cpp index e0844412..ece835d1 100644 --- a/src/key.cpp +++ b/src/key.cpp @@ -2,8 +2,10 @@ // Distributed under the MIT/X11 software license, see the accompanying // file license.txt or http://www.opensource.org/licenses/mit-license.php. -#include #include +#include + +#include "key.h" // Generate a private key from just the secret parameter int EC_KEY_regenerate_key(EC_KEY *eckey, BIGNUM *priv_key) @@ -115,3 +117,262 @@ err: if (Q != NULL) EC_POINT_free(Q); return ret; } + +void CKey::SetCompressedPubKey() +{ + EC_KEY_set_conv_form(pkey, POINT_CONVERSION_COMPRESSED); + fCompressedPubKey = true; +} + +void CKey::Reset() +{ + fCompressedPubKey = false; + pkey = EC_KEY_new_by_curve_name(NID_secp256k1); + if (pkey == NULL) + throw key_error("CKey::CKey() : EC_KEY_new_by_curve_name failed"); + fSet = false; +} + +CKey::CKey() +{ + Reset(); +} + +CKey::CKey(const CKey& b) +{ + pkey = EC_KEY_dup(b.pkey); + if (pkey == NULL) + throw key_error("CKey::CKey(const CKey&) : EC_KEY_dup failed"); + fSet = b.fSet; +} + +CKey& CKey::operator=(const CKey& b) +{ + if (!EC_KEY_copy(pkey, b.pkey)) + throw key_error("CKey::operator=(const CKey&) : EC_KEY_copy failed"); + fSet = b.fSet; + return (*this); +} + +CKey::~CKey() +{ + EC_KEY_free(pkey); +} + +bool CKey::IsNull() const +{ + return !fSet; +} + +bool CKey::IsCompressed() const +{ + return fCompressedPubKey; +} + +void CKey::MakeNewKey(bool fCompressed) +{ + if (!EC_KEY_generate_key(pkey)) + throw key_error("CKey::MakeNewKey() : EC_KEY_generate_key failed"); + if (fCompressed) + SetCompressedPubKey(); + fSet = true; +} + +bool CKey::SetPrivKey(const CPrivKey& vchPrivKey) +{ + const unsigned char* pbegin = &vchPrivKey[0]; + if (!d2i_ECPrivateKey(&pkey, &pbegin, vchPrivKey.size())) + return false; + fSet = true; + return true; +} + +bool CKey::SetSecret(const CSecret& vchSecret, bool fCompressed) +{ + EC_KEY_free(pkey); + pkey = EC_KEY_new_by_curve_name(NID_secp256k1); + if (pkey == NULL) + throw key_error("CKey::SetSecret() : EC_KEY_new_by_curve_name failed"); + if (vchSecret.size() != 32) + throw key_error("CKey::SetSecret() : secret must be 32 bytes"); + BIGNUM *bn = BN_bin2bn(&vchSecret[0],32,BN_new()); + if (bn == NULL) + throw key_error("CKey::SetSecret() : BN_bin2bn failed"); + if (!EC_KEY_regenerate_key(pkey,bn)) + { + BN_clear_free(bn); + throw key_error("CKey::SetSecret() : EC_KEY_regenerate_key failed"); + } + BN_clear_free(bn); + fSet = true; + if (fCompressed || fCompressedPubKey) + SetCompressedPubKey(); + return true; +} + +CSecret CKey::GetSecret(bool &fCompressed) const +{ + CSecret vchRet; + vchRet.resize(32); + const BIGNUM *bn = EC_KEY_get0_private_key(pkey); + int nBytes = BN_num_bytes(bn); + if (bn == NULL) + throw key_error("CKey::GetSecret() : EC_KEY_get0_private_key failed"); + int n=BN_bn2bin(bn,&vchRet[32 - nBytes]); + if (n != nBytes) + throw key_error("CKey::GetSecret(): BN_bn2bin failed"); + fCompressed = fCompressedPubKey; + return vchRet; +} + +CPrivKey CKey::GetPrivKey() const +{ + int nSize = i2d_ECPrivateKey(pkey, NULL); + if (!nSize) + throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey failed"); + CPrivKey vchPrivKey(nSize, 0); + unsigned char* pbegin = &vchPrivKey[0]; + if (i2d_ECPrivateKey(pkey, &pbegin) != nSize) + throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey returned unexpected size"); + return vchPrivKey; +} + +bool CKey::SetPubKey(const std::vector& vchPubKey) +{ + const unsigned char* pbegin = &vchPubKey[0]; + if (!o2i_ECPublicKey(&pkey, &pbegin, vchPubKey.size())) + return false; + fSet = true; + if (vchPubKey.size() == 33) + SetCompressedPubKey(); + return true; +} + +std::vector CKey::GetPubKey() const +{ + int nSize = i2o_ECPublicKey(pkey, NULL); + if (!nSize) + throw key_error("CKey::GetPubKey() : i2o_ECPublicKey failed"); + std::vector vchPubKey(nSize, 0); + unsigned char* pbegin = &vchPubKey[0]; + if (i2o_ECPublicKey(pkey, &pbegin) != nSize) + throw key_error("CKey::GetPubKey() : i2o_ECPublicKey returned unexpected size"); + return vchPubKey; +} + +bool CKey::Sign(uint256 hash, std::vector& vchSig) +{ + unsigned int nSize = ECDSA_size(pkey); + vchSig.resize(nSize); // Make sure it is big enough + if (!ECDSA_sign(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], &nSize, pkey)) + { + vchSig.clear(); + return false; + } + vchSig.resize(nSize); // Shrink to fit actual size + return true; +} + +// create a compact signature (65 bytes), which allows reconstructing the used public key +// The format is one header byte, followed by two times 32 bytes for the serialized r and s values. +// The header byte: 0x1B = first key with even y, 0x1C = first key with odd y, +// 0x1D = second key with even y, 0x1E = second key with odd y +bool CKey::SignCompact(uint256 hash, std::vector& vchSig) +{ + bool fOk = false; + ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey); + if (sig==NULL) + return false; + vchSig.clear(); + vchSig.resize(65,0); + int nBitsR = BN_num_bits(sig->r); + int nBitsS = BN_num_bits(sig->s); + if (nBitsR <= 256 && nBitsS <= 256) + { + int nRecId = -1; + for (int i=0; i<4; i++) + { + CKey keyRec; + keyRec.fSet = true; + if (fCompressedPubKey) + keyRec.SetCompressedPubKey(); + if (ECDSA_SIG_recover_key_GFp(keyRec.pkey, sig, (unsigned char*)&hash, sizeof(hash), i, 1) == 1) + if (keyRec.GetPubKey() == this->GetPubKey()) + { + nRecId = i; + break; + } + } + + if (nRecId == -1) + throw key_error("CKey::SignCompact() : unable to construct recoverable key"); + + vchSig[0] = nRecId+27+(fCompressedPubKey ? 4 : 0); + BN_bn2bin(sig->r,&vchSig[33-(nBitsR+7)/8]); + BN_bn2bin(sig->s,&vchSig[65-(nBitsS+7)/8]); + fOk = true; + } + ECDSA_SIG_free(sig); + return fOk; +} + +// reconstruct public key from a compact signature +// This is only slightly more CPU intensive than just verifying it. +// If this function succeeds, the recovered public key is guaranteed to be valid +// (the signature is a valid signature of the given data for that key) +bool CKey::SetCompactSignature(uint256 hash, const std::vector& vchSig) +{ + if (vchSig.size() != 65) + return false; + int nV = vchSig[0]; + if (nV<27 || nV>=35) + return false; + ECDSA_SIG *sig = ECDSA_SIG_new(); + BN_bin2bn(&vchSig[1],32,sig->r); + BN_bin2bn(&vchSig[33],32,sig->s); + + EC_KEY_free(pkey); + pkey = EC_KEY_new_by_curve_name(NID_secp256k1); + if (nV >= 31) + { + SetCompressedPubKey(); + nV -= 4; + } + if (ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), nV - 27, 0) == 1) + { + fSet = true; + ECDSA_SIG_free(sig); + return true; + } + return false; +} + +bool CKey::Verify(uint256 hash, const std::vector& vchSig) +{ + // -1 = error, 0 = bad sig, 1 = good + if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1) + return false; + return true; +} + +bool CKey::VerifyCompact(uint256 hash, const std::vector& vchSig) +{ + CKey key; + if (!key.SetCompactSignature(hash, vchSig)) + return false; + if (GetPubKey() != key.GetPubKey()) + return false; + return true; +} + +bool CKey::IsValid() +{ + if (!fSet) + return false; + + bool fCompr; + CSecret secret = GetSecret(fCompr); + CKey key2; + key2.SetSecret(secret, fCompr); + return GetPubKey() == key2.GetPubKey(); +} diff --git a/src/key.h b/src/key.h index 1579cdc4..f7255fca 100644 --- a/src/key.h +++ b/src/key.h @@ -8,13 +8,11 @@ #include #include -#include -#include -#include - #include "allocators.h" #include "uint256.h" +#include // for EC_KEY definition + // secp160k1 // const unsigned int PRIVATE_KEY_SIZE = 192; // const unsigned int PUBLIC_KEY_SIZE = 41; @@ -38,9 +36,6 @@ // see www.keylength.com // script supports up to 75 for single byte push -int extern EC_KEY_regenerate_key(EC_KEY *eckey, BIGNUM *priv_key); -int extern ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned char *msg, int msglen, int recid, int check); - class key_error : public std::runtime_error { public: @@ -62,267 +57,50 @@ protected: bool fSet; bool fCompressedPubKey; - void SetCompressedPubKey() - { - EC_KEY_set_conv_form(pkey, POINT_CONVERSION_COMPRESSED); - fCompressedPubKey = true; - } + void SetCompressedPubKey(); public: - void Reset() - { - fCompressedPubKey = false; - pkey = EC_KEY_new_by_curve_name(NID_secp256k1); - if (pkey == NULL) - throw key_error("CKey::CKey() : EC_KEY_new_by_curve_name failed"); - fSet = false; - } - - CKey() - { - Reset(); - } - - CKey(const CKey& b) - { - pkey = EC_KEY_dup(b.pkey); - if (pkey == NULL) - throw key_error("CKey::CKey(const CKey&) : EC_KEY_dup failed"); - fSet = b.fSet; - } - - CKey& operator=(const CKey& b) - { - if (!EC_KEY_copy(pkey, b.pkey)) - throw key_error("CKey::operator=(const CKey&) : EC_KEY_copy failed"); - fSet = b.fSet; - return (*this); - } - - ~CKey() - { - EC_KEY_free(pkey); - } - - bool IsNull() const - { - return !fSet; - } + void Reset(); - bool IsCompressed() const - { - return fCompressedPubKey; - } + CKey(); + CKey(const CKey& b); - void MakeNewKey(bool fCompressed) - { - if (!EC_KEY_generate_key(pkey)) - throw key_error("CKey::MakeNewKey() : EC_KEY_generate_key failed"); - if (fCompressed) - SetCompressedPubKey(); - fSet = true; - } + CKey& operator=(const CKey& b); - bool SetPrivKey(const CPrivKey& vchPrivKey) - { - const unsigned char* pbegin = &vchPrivKey[0]; - if (!d2i_ECPrivateKey(&pkey, &pbegin, vchPrivKey.size())) - return false; - fSet = true; - return true; - } + ~CKey(); - bool SetSecret(const CSecret& vchSecret, bool fCompressed = false) - { - EC_KEY_free(pkey); - pkey = EC_KEY_new_by_curve_name(NID_secp256k1); - if (pkey == NULL) - throw key_error("CKey::SetSecret() : EC_KEY_new_by_curve_name failed"); - if (vchSecret.size() != 32) - throw key_error("CKey::SetSecret() : secret must be 32 bytes"); - BIGNUM *bn = BN_bin2bn(&vchSecret[0],32,BN_new()); - if (bn == NULL) - throw key_error("CKey::SetSecret() : BN_bin2bn failed"); - if (!EC_KEY_regenerate_key(pkey,bn)) - { - BN_clear_free(bn); - throw key_error("CKey::SetSecret() : EC_KEY_regenerate_key failed"); - } - BN_clear_free(bn); - fSet = true; - if (fCompressed || fCompressedPubKey) - SetCompressedPubKey(); - return true; - } + bool IsNull() const; + bool IsCompressed() const; - CSecret GetSecret(bool &fCompressed) const - { - CSecret vchRet; - vchRet.resize(32); - const BIGNUM *bn = EC_KEY_get0_private_key(pkey); - int nBytes = BN_num_bytes(bn); - if (bn == NULL) - throw key_error("CKey::GetSecret() : EC_KEY_get0_private_key failed"); - int n=BN_bn2bin(bn,&vchRet[32 - nBytes]); - if (n != nBytes) - throw key_error("CKey::GetSecret(): BN_bn2bin failed"); - fCompressed = fCompressedPubKey; - return vchRet; - } + void MakeNewKey(bool fCompressed); + bool SetPrivKey(const CPrivKey& vchPrivKey); + bool SetSecret(const CSecret& vchSecret, bool fCompressed = false); + CSecret GetSecret(bool &fCompressed) const; + CPrivKey GetPrivKey() const; + bool SetPubKey(const std::vector& vchPubKey); + std::vector GetPubKey() const; - CPrivKey GetPrivKey() const - { - int nSize = i2d_ECPrivateKey(pkey, NULL); - if (!nSize) - throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey failed"); - CPrivKey vchPrivKey(nSize, 0); - unsigned char* pbegin = &vchPrivKey[0]; - if (i2d_ECPrivateKey(pkey, &pbegin) != nSize) - throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey returned unexpected size"); - return vchPrivKey; - } - - bool SetPubKey(const std::vector& vchPubKey) - { - const unsigned char* pbegin = &vchPubKey[0]; - if (!o2i_ECPublicKey(&pkey, &pbegin, vchPubKey.size())) - return false; - fSet = true; - if (vchPubKey.size() == 33) - SetCompressedPubKey(); - return true; - } - - std::vector GetPubKey() const - { - int nSize = i2o_ECPublicKey(pkey, NULL); - if (!nSize) - throw key_error("CKey::GetPubKey() : i2o_ECPublicKey failed"); - std::vector vchPubKey(nSize, 0); - unsigned char* pbegin = &vchPubKey[0]; - if (i2o_ECPublicKey(pkey, &pbegin) != nSize) - throw key_error("CKey::GetPubKey() : i2o_ECPublicKey returned unexpected size"); - return vchPubKey; - } - - bool Sign(uint256 hash, std::vector& vchSig) - { - unsigned int nSize = ECDSA_size(pkey); - vchSig.resize(nSize); // Make sure it is big enough - if (!ECDSA_sign(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], &nSize, pkey)) - { - vchSig.clear(); - return false; - } - vchSig.resize(nSize); // Shrink to fit actual size - return true; - } + bool Sign(uint256 hash, std::vector& vchSig); // create a compact signature (65 bytes), which allows reconstructing the used public key // The format is one header byte, followed by two times 32 bytes for the serialized r and s values. // The header byte: 0x1B = first key with even y, 0x1C = first key with odd y, // 0x1D = second key with even y, 0x1E = second key with odd y - bool SignCompact(uint256 hash, std::vector& vchSig) - { - bool fOk = false; - ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey); - if (sig==NULL) - return false; - vchSig.clear(); - vchSig.resize(65,0); - int nBitsR = BN_num_bits(sig->r); - int nBitsS = BN_num_bits(sig->s); - if (nBitsR <= 256 && nBitsS <= 256) - { - int nRecId = -1; - for (int i=0; i<4; i++) - { - CKey keyRec; - keyRec.fSet = true; - if (fCompressedPubKey) - keyRec.SetCompressedPubKey(); - if (ECDSA_SIG_recover_key_GFp(keyRec.pkey, sig, (unsigned char*)&hash, sizeof(hash), i, 1) == 1) - if (keyRec.GetPubKey() == this->GetPubKey()) - { - nRecId = i; - break; - } - } - - if (nRecId == -1) - throw key_error("CKey::SignCompact() : unable to construct recoverable key"); - - vchSig[0] = nRecId+27+(fCompressedPubKey ? 4 : 0); - BN_bn2bin(sig->r,&vchSig[33-(nBitsR+7)/8]); - BN_bn2bin(sig->s,&vchSig[65-(nBitsS+7)/8]); - fOk = true; - } - ECDSA_SIG_free(sig); - return fOk; - } + bool SignCompact(uint256 hash, std::vector& vchSig); // reconstruct public key from a compact signature // This is only slightly more CPU intensive than just verifying it. // If this function succeeds, the recovered public key is guaranteed to be valid // (the signature is a valid signature of the given data for that key) - bool SetCompactSignature(uint256 hash, const std::vector& vchSig) - { - if (vchSig.size() != 65) - return false; - int nV = vchSig[0]; - if (nV<27 || nV>=35) - return false; - ECDSA_SIG *sig = ECDSA_SIG_new(); - BN_bin2bn(&vchSig[1],32,sig->r); - BN_bin2bn(&vchSig[33],32,sig->s); - - EC_KEY_free(pkey); - pkey = EC_KEY_new_by_curve_name(NID_secp256k1); - if (nV >= 31) - { - SetCompressedPubKey(); - nV -= 4; - } - if (ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), nV - 27, 0) == 1) - { - fSet = true; - ECDSA_SIG_free(sig); - return true; - } - return false; - } + bool SetCompactSignature(uint256 hash, const std::vector& vchSig); - bool Verify(uint256 hash, const std::vector& vchSig) - { - // -1 = error, 0 = bad sig, 1 = good - if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1) - return false; - return true; - } + bool Verify(uint256 hash, const std::vector& vchSig); // Verify a compact signature - bool VerifyCompact(uint256 hash, const std::vector& vchSig) - { - CKey key; - if (!key.SetCompactSignature(hash, vchSig)) - return false; - if (GetPubKey() != key.GetPubKey()) - return false; - return true; - } - - bool IsValid() - { - if (!fSet) - return false; + bool VerifyCompact(uint256 hash, const std::vector& vchSig); - bool fCompr; - CSecret secret = GetSecret(fCompr); - CKey key2; - key2.SetSecret(secret, fCompr); - return GetPubKey() == key2.GetPubKey(); - } + bool IsValid(); }; #endif