// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2012 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
-// file license.txt or http://www.opensource.org/licenses/mit-license.php.
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_KEY_H
#define BITCOIN_KEY_H
#include <stdexcept>
#include <vector>
-#include <openssl/ec.h>
-#include <openssl/ecdsa.h>
-#include <openssl/obj_mac.h>
-
-#include "serialize.h"
+#include "allocators.h"
#include "uint256.h"
-#include "base58.h"
+
+#include <openssl/ec.h> // for EC_KEY definition
// secp160k1
// const unsigned int PRIVATE_KEY_SIZE = 192;
// see www.keylength.com
// script supports up to 75 for single byte push
-// Generate a private key from just the secret parameter
-int static inline EC_KEY_regenerate_key(EC_KEY *eckey, BIGNUM *priv_key)
-{
- int ok = 0;
- BN_CTX *ctx = NULL;
- EC_POINT *pub_key = NULL;
-
- if (!eckey) return 0;
-
- const EC_GROUP *group = EC_KEY_get0_group(eckey);
-
- if ((ctx = BN_CTX_new()) == NULL)
- goto err;
-
- pub_key = EC_POINT_new(group);
-
- if (pub_key == NULL)
- goto err;
-
- if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx))
- goto err;
-
- EC_KEY_set_private_key(eckey,priv_key);
- EC_KEY_set_public_key(eckey,pub_key);
-
- ok = 1;
-
-err:
-
- if (pub_key)
- EC_POINT_free(pub_key);
- if (ctx != NULL)
- BN_CTX_free(ctx);
-
- return(ok);
-}
-
-// Perform ECDSA key recovery (see SEC1 4.1.6) for curves over (mod p)-fields
-// recid selects which key is recovered
-// if check is nonzero, additional checks are performed
-int static inline ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned char *msg, int msglen, int recid, int check)
-{
- if (!eckey) return 0;
-
- int ret = 0;
- BN_CTX *ctx = NULL;
-
- BIGNUM *x = NULL;
- BIGNUM *e = NULL;
- BIGNUM *order = NULL;
- BIGNUM *sor = NULL;
- BIGNUM *eor = NULL;
- BIGNUM *field = NULL;
- EC_POINT *R = NULL;
- EC_POINT *O = NULL;
- EC_POINT *Q = NULL;
- BIGNUM *rr = NULL;
- BIGNUM *zero = NULL;
- int n = 0;
- int i = recid / 2;
-
- const EC_GROUP *group = EC_KEY_get0_group(eckey);
- if ((ctx = BN_CTX_new()) == NULL) { ret = -1; goto err; }
- BN_CTX_start(ctx);
- order = BN_CTX_get(ctx);
- if (!EC_GROUP_get_order(group, order, ctx)) { ret = -2; goto err; }
- x = BN_CTX_get(ctx);
- if (!BN_copy(x, order)) { ret=-1; goto err; }
- if (!BN_mul_word(x, i)) { ret=-1; goto err; }
- if (!BN_add(x, x, ecsig->r)) { ret=-1; goto err; }
- field = BN_CTX_get(ctx);
- if (!EC_GROUP_get_curve_GFp(group, field, NULL, NULL, ctx)) { ret=-2; goto err; }
- if (BN_cmp(x, field) >= 0) { ret=0; goto err; }
- if ((R = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
- if (!EC_POINT_set_compressed_coordinates_GFp(group, R, x, recid % 2, ctx)) { ret=0; goto err; }
- if (check)
- {
- if ((O = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
- if (!EC_POINT_mul(group, O, NULL, R, order, ctx)) { ret=-2; goto err; }
- if (!EC_POINT_is_at_infinity(group, O)) { ret = 0; goto err; }
- }
- if ((Q = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
- n = EC_GROUP_get_degree(group);
- e = BN_CTX_get(ctx);
- if (!BN_bin2bn(msg, msglen, e)) { ret=-1; goto err; }
- if (8*msglen > n) BN_rshift(e, e, 8-(n & 7));
- zero = BN_CTX_get(ctx);
- if (!BN_zero(zero)) { ret=-1; goto err; }
- if (!BN_mod_sub(e, zero, e, order, ctx)) { ret=-1; goto err; }
- rr = BN_CTX_get(ctx);
- if (!BN_mod_inverse(rr, ecsig->r, order, ctx)) { ret=-1; goto err; }
- sor = BN_CTX_get(ctx);
- if (!BN_mod_mul(sor, ecsig->s, rr, order, ctx)) { ret=-1; goto err; }
- eor = BN_CTX_get(ctx);
- if (!BN_mod_mul(eor, e, rr, order, ctx)) { ret=-1; goto err; }
- if (!EC_POINT_mul(group, Q, eor, R, sor, ctx)) { ret=-2; goto err; }
- if (!EC_KEY_set_public_key(eckey, Q)) { ret=-2; goto err; }
-
- ret = 1;
-
-err:
- if (ctx) {
- BN_CTX_end(ctx);
- BN_CTX_free(ctx);
- }
- if (R != NULL) EC_POINT_free(R);
- if (O != NULL) EC_POINT_free(O);
- if (Q != NULL) EC_POINT_free(Q);
- return ret;
-}
-
class key_error : public std::runtime_error
{
public:
// CSecret is a serialization of just the secret parameter (32 bytes)
typedef std::vector<unsigned char, secure_allocator<unsigned char> > CSecret;
+/** An encapsulated OpenSSL Elliptic Curve key (public and/or private) */
class CKey
{
protected:
EC_KEY* pkey;
bool fSet;
+ bool fCompressedPubKey;
-public:
- CKey()
- {
- 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(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);
- }
+ void SetCompressedPubKey();
- ~CKey()
- {
- EC_KEY_free(pkey);
- }
-
- bool IsNull() const
- {
- return !fSet;
- }
-
- void MakeNewKey()
- {
- if (!EC_KEY_generate_key(pkey))
- throw key_error("CKey::MakeNewKey() : EC_KEY_generate_key failed");
- fSet = true;
- }
+public:
- bool SetPrivKey(const CPrivKey& vchPrivKey)
- {
- const unsigned char* pbegin = &vchPrivKey[0];
- if (!d2i_ECPrivateKey(&pkey, &pbegin, vchPrivKey.size()))
- return false;
- fSet = true;
- return true;
- }
+ void Reset();
- bool SetSecret(const CSecret& vchSecret)
- {
- 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))
- throw key_error("CKey::SetSecret() : EC_KEY_regenerate_key failed");
- BN_clear_free(bn);
- fSet = true;
- return true;
- }
+ CKey();
+ CKey(const CKey& b);
- CSecret GetSecret() 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");
- return vchRet;
- }
+ CKey& operator=(const CKey& b);
- CPrivKey GetPrivKey() const
- {
- unsigned 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;
- }
+ ~CKey();
- bool SetPubKey(const std::vector<unsigned char>& vchPubKey)
- {
- const unsigned char* pbegin = &vchPubKey[0];
- if (!o2i_ECPublicKey(&pkey, &pbegin, vchPubKey.size()))
- return false;
- fSet = true;
- return true;
- }
+ bool IsNull() const;
+ bool IsCompressed() const;
- std::vector<unsigned char> GetPubKey() const
- {
- unsigned int nSize = i2o_ECPublicKey(pkey, NULL);
- if (!nSize)
- throw key_error("CKey::GetPubKey() : i2o_ECPublicKey failed");
- std::vector<unsigned char> 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;
- }
+ 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<unsigned char>& vchPubKey);
+ std::vector<unsigned char> GetPubKey() const;
- bool Sign(uint256 hash, std::vector<unsigned char>& vchSig)
- {
- vchSig.clear();
- unsigned char pchSig[10000];
- unsigned int nSize = 0;
- if (!ECDSA_sign(0, (unsigned char*)&hash, sizeof(hash), pchSig, &nSize, pkey))
- return false;
- vchSig.resize(nSize);
- memcpy(&vchSig[0], pchSig, nSize);
- return true;
- }
+ bool Sign(uint256 hash, std::vector<unsigned char>& 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<unsigned char>& 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 (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;
- 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<unsigned char>& 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<unsigned char>& vchSig)
- {
- if (vchSig.size() != 65)
- return false;
- if (vchSig[0]<27 || vchSig[0]>=31)
- 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 (ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), vchSig[0] - 27, 0) == 1)
- {
- fSet = true;
- ECDSA_SIG_free(sig);
- return true;
- }
- return false;
- }
+ bool SetCompactSignature(uint256 hash, const std::vector<unsigned char>& vchSig);
- bool Verify(uint256 hash, const std::vector<unsigned char>& 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<unsigned char>& vchSig);
// Verify a compact signature
- bool VerifyCompact(uint256 hash, const std::vector<unsigned char>& vchSig)
- {
- CKey key;
- if (!key.SetCompactSignature(hash, vchSig))
- return false;
- if (GetPubKey() != key.GetPubKey())
- return false;
- return true;
- }
-
- // Get the address corresponding to this key
- CBitcoinAddress GetAddress() const
- {
- return CBitcoinAddress(GetPubKey());
- }
-
- bool IsValid()
- {
- if (!fSet)
- return false;
+ bool VerifyCompact(uint256 hash, const std::vector<unsigned char>& vchSig);
- CSecret secret = GetSecret();
- CKey key2;
- key2.SetSecret(secret);
- return GetPubKey() == key2.GetPubKey();
- }
+ bool IsValid();
};
#endif
git://git.novaco.in / novacoin.git / blobdiff