Merge pull request #5118
50f71cdboost: code movement only: split CECKey into separate files (Cory Fields)bdaec6aboost: remove CPubKey dependency from CECKey. Follow-up ofe405aa48(Cory Fields)
This commit is contained in:
Pieter Wuille
commit
068b7f8ee2
@ -84,6 +84,7 @@ BITCOIN_CORE_H = \
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core_io.h \
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crypter.h \
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db.h \
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ecwrapper.h \
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hash.h \
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init.h \
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key.h \
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@ -214,6 +215,7 @@ libbitcoin_common_a_SOURCES = \
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core.cpp \
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core_read.cpp \
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core_write.cpp \
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ecwrapper.cpp \
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hash.cpp \
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key.cpp \
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keystore.cpp \
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333
src/ecwrapper.cpp
Normal file
333
src/ecwrapper.cpp
Normal file
@ -0,0 +1,333 @@
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// Copyright (c) 2009-2014 The Bitcoin developers
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// Distributed under the MIT/X11 software license, see the accompanying
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// file COPYING or http://www.opensource.org/licenses/mit-license.php.
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#include "ecwrapper.h"
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#include "serialize.h"
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#include "uint256.h"
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#include <openssl/bn.h>
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#include <openssl/ecdsa.h>
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#include <openssl/obj_mac.h>
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namespace {
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// Generate a private key from just the secret parameter
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int EC_KEY_regenerate_key(EC_KEY *eckey, BIGNUM *priv_key)
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{
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int ok = 0;
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BN_CTX *ctx = NULL;
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EC_POINT *pub_key = NULL;
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if (!eckey) return 0;
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const EC_GROUP *group = EC_KEY_get0_group(eckey);
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if ((ctx = BN_CTX_new()) == NULL)
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goto err;
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pub_key = EC_POINT_new(group);
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if (pub_key == NULL)
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goto err;
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if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx))
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goto err;
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EC_KEY_set_private_key(eckey,priv_key);
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EC_KEY_set_public_key(eckey,pub_key);
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ok = 1;
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err:
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if (pub_key)
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EC_POINT_free(pub_key);
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if (ctx != NULL)
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BN_CTX_free(ctx);
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return(ok);
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}
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// Perform ECDSA key recovery (see SEC1 4.1.6) for curves over (mod p)-fields
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// recid selects which key is recovered
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// if check is non-zero, additional checks are performed
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int ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned char *msg, int msglen, int recid, int check)
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{
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if (!eckey) return 0;
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int ret = 0;
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BN_CTX *ctx = NULL;
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BIGNUM *x = NULL;
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BIGNUM *e = NULL;
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BIGNUM *order = NULL;
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BIGNUM *sor = NULL;
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BIGNUM *eor = NULL;
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BIGNUM *field = NULL;
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EC_POINT *R = NULL;
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EC_POINT *O = NULL;
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EC_POINT *Q = NULL;
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BIGNUM *rr = NULL;
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BIGNUM *zero = NULL;
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int n = 0;
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int i = recid / 2;
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const EC_GROUP *group = EC_KEY_get0_group(eckey);
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if ((ctx = BN_CTX_new()) == NULL) { ret = -1; goto err; }
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BN_CTX_start(ctx);
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order = BN_CTX_get(ctx);
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if (!EC_GROUP_get_order(group, order, ctx)) { ret = -2; goto err; }
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x = BN_CTX_get(ctx);
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if (!BN_copy(x, order)) { ret=-1; goto err; }
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if (!BN_mul_word(x, i)) { ret=-1; goto err; }
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if (!BN_add(x, x, ecsig->r)) { ret=-1; goto err; }
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field = BN_CTX_get(ctx);
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if (!EC_GROUP_get_curve_GFp(group, field, NULL, NULL, ctx)) { ret=-2; goto err; }
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if (BN_cmp(x, field) >= 0) { ret=0; goto err; }
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if ((R = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
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if (!EC_POINT_set_compressed_coordinates_GFp(group, R, x, recid % 2, ctx)) { ret=0; goto err; }
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if (check)
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{
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if ((O = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
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if (!EC_POINT_mul(group, O, NULL, R, order, ctx)) { ret=-2; goto err; }
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if (!EC_POINT_is_at_infinity(group, O)) { ret = 0; goto err; }
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}
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if ((Q = EC_POINT_new(group)) == NULL) { ret = -2; goto err; }
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n = EC_GROUP_get_degree(group);
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e = BN_CTX_get(ctx);
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if (!BN_bin2bn(msg, msglen, e)) { ret=-1; goto err; }
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if (8*msglen > n) BN_rshift(e, e, 8-(n & 7));
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zero = BN_CTX_get(ctx);
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if (!BN_zero(zero)) { ret=-1; goto err; }
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if (!BN_mod_sub(e, zero, e, order, ctx)) { ret=-1; goto err; }
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rr = BN_CTX_get(ctx);
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if (!BN_mod_inverse(rr, ecsig->r, order, ctx)) { ret=-1; goto err; }
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sor = BN_CTX_get(ctx);
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if (!BN_mod_mul(sor, ecsig->s, rr, order, ctx)) { ret=-1; goto err; }
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eor = BN_CTX_get(ctx);
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if (!BN_mod_mul(eor, e, rr, order, ctx)) { ret=-1; goto err; }
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if (!EC_POINT_mul(group, Q, eor, R, sor, ctx)) { ret=-2; goto err; }
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if (!EC_KEY_set_public_key(eckey, Q)) { ret=-2; goto err; }
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ret = 1;
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err:
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if (ctx) {
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BN_CTX_end(ctx);
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BN_CTX_free(ctx);
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}
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if (R != NULL) EC_POINT_free(R);
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if (O != NULL) EC_POINT_free(O);
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if (Q != NULL) EC_POINT_free(Q);
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return ret;
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}
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} // anon namespace
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CECKey::CECKey() {
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pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
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assert(pkey != NULL);
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}
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CECKey::~CECKey() {
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EC_KEY_free(pkey);
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}
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void CECKey::GetSecretBytes(unsigned char vch[32]) const {
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const BIGNUM *bn = EC_KEY_get0_private_key(pkey);
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assert(bn);
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int nBytes = BN_num_bytes(bn);
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int n=BN_bn2bin(bn,&vch[32 - nBytes]);
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assert(n == nBytes);
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memset(vch, 0, 32 - nBytes);
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}
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void CECKey::SetSecretBytes(const unsigned char vch[32]) {
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bool ret;
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BIGNUM bn;
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BN_init(&bn);
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ret = BN_bin2bn(vch, 32, &bn) != NULL;
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assert(ret);
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ret = EC_KEY_regenerate_key(pkey, &bn) != 0;
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assert(ret);
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BN_clear_free(&bn);
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}
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int CECKey::GetPrivKeySize(bool fCompressed) {
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EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
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return i2d_ECPrivateKey(pkey, NULL);
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}
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int CECKey::GetPrivKey(unsigned char* privkey, bool fCompressed) {
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EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
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return i2d_ECPrivateKey(pkey, &privkey);
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}
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bool CECKey::SetPrivKey(const unsigned char* privkey, size_t size, bool fSkipCheck) {
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if (d2i_ECPrivateKey(&pkey, &privkey, size)) {
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if(fSkipCheck)
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return true;
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// d2i_ECPrivateKey returns true if parsing succeeds.
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// This doesn't necessarily mean the key is valid.
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if (EC_KEY_check_key(pkey))
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return true;
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}
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return false;
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}
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void CECKey::GetPubKey(std::vector<unsigned char> &pubkey, bool fCompressed) {
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EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
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int nSize = i2o_ECPublicKey(pkey, NULL);
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assert(nSize);
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assert(nSize <= 65);
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pubkey.clear();
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pubkey.resize(nSize);
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unsigned char *pbegin(begin_ptr(pubkey));
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int nSize2 = i2o_ECPublicKey(pkey, &pbegin);
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assert(nSize == nSize2);
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}
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bool CECKey::SetPubKey(const unsigned char* pubkey, size_t size) {
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return o2i_ECPublicKey(&pkey, &pubkey, size) != NULL;
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}
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bool CECKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool lowS) {
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vchSig.clear();
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ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
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if (sig == NULL)
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return false;
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BN_CTX *ctx = BN_CTX_new();
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BN_CTX_start(ctx);
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const EC_GROUP *group = EC_KEY_get0_group(pkey);
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BIGNUM *order = BN_CTX_get(ctx);
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BIGNUM *halforder = BN_CTX_get(ctx);
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EC_GROUP_get_order(group, order, ctx);
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BN_rshift1(halforder, order);
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if (lowS && BN_cmp(sig->s, halforder) > 0) {
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// enforce low S values, by negating the value (modulo the order) if above order/2.
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BN_sub(sig->s, order, sig->s);
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}
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BN_CTX_end(ctx);
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BN_CTX_free(ctx);
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unsigned int nSize = ECDSA_size(pkey);
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vchSig.resize(nSize); // Make sure it is big enough
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unsigned char *pos = &vchSig[0];
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nSize = i2d_ECDSA_SIG(sig, &pos);
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ECDSA_SIG_free(sig);
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vchSig.resize(nSize); // Shrink to fit actual size
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return true;
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}
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bool CECKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig) {
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// -1 = error, 0 = bad sig, 1 = good
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if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1)
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return false;
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return true;
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}
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bool CECKey::SignCompact(const uint256 &hash, unsigned char *p64, int &rec) {
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bool fOk = false;
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ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
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if (sig==NULL)
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return false;
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memset(p64, 0, 64);
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int nBitsR = BN_num_bits(sig->r);
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int nBitsS = BN_num_bits(sig->s);
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if (nBitsR <= 256 && nBitsS <= 256) {
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std::vector<unsigned char> pubkey;
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GetPubKey(pubkey, true);
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for (int i=0; i<4; i++) {
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CECKey keyRec;
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if (ECDSA_SIG_recover_key_GFp(keyRec.pkey, sig, (unsigned char*)&hash, sizeof(hash), i, 1) == 1) {
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std::vector<unsigned char> pubkeyRec;
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keyRec.GetPubKey(pubkeyRec, true);
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if (pubkeyRec == pubkey) {
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rec = i;
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fOk = true;
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break;
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}
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}
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}
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assert(fOk);
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BN_bn2bin(sig->r,&p64[32-(nBitsR+7)/8]);
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BN_bn2bin(sig->s,&p64[64-(nBitsS+7)/8]);
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}
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ECDSA_SIG_free(sig);
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return fOk;
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}
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bool CECKey::Recover(const uint256 &hash, const unsigned char *p64, int rec)
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{
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if (rec<0 || rec>=3)
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return false;
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ECDSA_SIG *sig = ECDSA_SIG_new();
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BN_bin2bn(&p64[0], 32, sig->r);
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BN_bin2bn(&p64[32], 32, sig->s);
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bool ret = ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), rec, 0) == 1;
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ECDSA_SIG_free(sig);
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return ret;
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}
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bool CECKey::TweakSecret(unsigned char vchSecretOut[32], const unsigned char vchSecretIn[32], const unsigned char vchTweak[32])
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{
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bool ret = true;
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BN_CTX *ctx = BN_CTX_new();
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BN_CTX_start(ctx);
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BIGNUM *bnSecret = BN_CTX_get(ctx);
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BIGNUM *bnTweak = BN_CTX_get(ctx);
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BIGNUM *bnOrder = BN_CTX_get(ctx);
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EC_GROUP *group = EC_GROUP_new_by_curve_name(NID_secp256k1);
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EC_GROUP_get_order(group, bnOrder, ctx); // what a grossly inefficient way to get the (constant) group order...
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BN_bin2bn(vchTweak, 32, bnTweak);
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if (BN_cmp(bnTweak, bnOrder) >= 0)
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ret = false; // extremely unlikely
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BN_bin2bn(vchSecretIn, 32, bnSecret);
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BN_add(bnSecret, bnSecret, bnTweak);
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BN_nnmod(bnSecret, bnSecret, bnOrder, ctx);
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if (BN_is_zero(bnSecret))
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ret = false; // ridiculously unlikely
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int nBits = BN_num_bits(bnSecret);
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memset(vchSecretOut, 0, 32);
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BN_bn2bin(bnSecret, &vchSecretOut[32-(nBits+7)/8]);
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EC_GROUP_free(group);
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BN_CTX_end(ctx);
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BN_CTX_free(ctx);
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return ret;
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}
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bool CECKey::TweakPublic(const unsigned char vchTweak[32]) {
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bool ret = true;
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BN_CTX *ctx = BN_CTX_new();
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BN_CTX_start(ctx);
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BIGNUM *bnTweak = BN_CTX_get(ctx);
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BIGNUM *bnOrder = BN_CTX_get(ctx);
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BIGNUM *bnOne = BN_CTX_get(ctx);
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const EC_GROUP *group = EC_KEY_get0_group(pkey);
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EC_GROUP_get_order(group, bnOrder, ctx); // what a grossly inefficient way to get the (constant) group order...
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BN_bin2bn(vchTweak, 32, bnTweak);
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if (BN_cmp(bnTweak, bnOrder) >= 0)
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ret = false; // extremely unlikely
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EC_POINT *point = EC_POINT_dup(EC_KEY_get0_public_key(pkey), group);
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BN_one(bnOne);
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EC_POINT_mul(group, point, bnTweak, point, bnOne, ctx);
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if (EC_POINT_is_at_infinity(group, point))
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ret = false; // ridiculously unlikely
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EC_KEY_set_public_key(pkey, point);
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EC_POINT_free(point);
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BN_CTX_end(ctx);
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BN_CTX_free(ctx);
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return ret;
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}
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bool CECKey::SanityCheck()
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{
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EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
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if(pkey == NULL)
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return false;
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EC_KEY_free(pkey);
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// TODO Is there more EC functionality that could be missing?
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return true;
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}
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46
src/ecwrapper.h
Normal file
46
src/ecwrapper.h
Normal file
@ -0,0 +1,46 @@
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// Copyright (c) 2009-2014 The Bitcoin developers
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||||
// Distributed under the MIT/X11 software license, see the accompanying
|
||||
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
|
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|
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#ifndef BITCOIN_EC_WRAPPER_H
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#define BITCOIN_EC_WRAPPER_H
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#include <cstddef>
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#include <vector>
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#include <openssl/ec.h>
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class uint256;
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// RAII Wrapper around OpenSSL's EC_KEY
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class CECKey {
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private:
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EC_KEY *pkey;
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public:
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CECKey();
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~CECKey();
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void GetSecretBytes(unsigned char vch[32]) const;
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void SetSecretBytes(const unsigned char vch[32]);
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int GetPrivKeySize(bool fCompressed);
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int GetPrivKey(unsigned char* privkey, bool fCompressed);
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bool SetPrivKey(const unsigned char* privkey, size_t size, bool fSkipCheck=false);
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void GetPubKey(std::vector<unsigned char>& pubkey, bool fCompressed);
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bool SetPubKey(const unsigned char* pubkey, size_t size);
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bool Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool lowS);
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bool Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig);
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bool SignCompact(const uint256 &hash, unsigned char *p64, int &rec);
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// reconstruct public key from a compact signature
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// This is only slightly more CPU intensive than just verifying it.
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// If this function succeeds, the recovered public key is guaranteed to be valid
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// (the signature is a valid signature of the given data for that key)
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bool Recover(const uint256 &hash, const unsigned char *p64, int rec);
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static bool TweakSecret(unsigned char vchSecretOut[32], const unsigned char vchSecretIn[32], const unsigned char vchTweak[32]);
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bool TweakPublic(const unsigned char vchTweak[32]);
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static bool SanityCheck();
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};
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#endif
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366
src/key.cpp
366
src/key.cpp
@ -10,12 +10,10 @@
|
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#ifdef USE_SECP256K1
|
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#include <secp256k1.h>
|
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#else
|
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#include <openssl/bn.h>
|
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#include <openssl/ecdsa.h>
|
||||
#include <openssl/obj_mac.h>
|
||||
#include "ecwrapper.h"
|
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#endif
|
||||
|
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// anonymous namespace with local implementation code (OpenSSL interaction)
|
||||
// anonymous namespace
|
||||
namespace {
|
||||
|
||||
#ifdef USE_SECP256K1
|
||||
@ -31,326 +29,6 @@ public:
|
||||
};
|
||||
static CSecp256k1Init instance_of_csecp256k1;
|
||||
|
||||
#else
|
||||
|
||||
// Generate a private key from just the secret parameter
|
||||
int 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 non-zero, additional checks are performed
|
||||
int 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;
|
||||
}
|
||||
|
||||
// RAII Wrapper around OpenSSL's EC_KEY
|
||||
class CECKey {
|
||||
private:
|
||||
EC_KEY *pkey;
|
||||
|
||||
public:
|
||||
CECKey() {
|
||||
pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
|
||||
assert(pkey != NULL);
|
||||
}
|
||||
|
||||
~CECKey() {
|
||||
EC_KEY_free(pkey);
|
||||
}
|
||||
|
||||
void GetSecretBytes(unsigned char vch[32]) const {
|
||||
const BIGNUM *bn = EC_KEY_get0_private_key(pkey);
|
||||
assert(bn);
|
||||
int nBytes = BN_num_bytes(bn);
|
||||
int n=BN_bn2bin(bn,&vch[32 - nBytes]);
|
||||
assert(n == nBytes);
|
||||
memset(vch, 0, 32 - nBytes);
|
||||
}
|
||||
|
||||
void SetSecretBytes(const unsigned char vch[32]) {
|
||||
bool ret;
|
||||
BIGNUM bn;
|
||||
BN_init(&bn);
|
||||
ret = BN_bin2bn(vch, 32, &bn) != NULL;
|
||||
assert(ret);
|
||||
ret = EC_KEY_regenerate_key(pkey, &bn) != 0;
|
||||
assert(ret);
|
||||
BN_clear_free(&bn);
|
||||
}
|
||||
|
||||
int GetPrivKeySize(bool fCompressed) {
|
||||
EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
|
||||
return i2d_ECPrivateKey(pkey, NULL);
|
||||
}
|
||||
int GetPrivKey(unsigned char* privkey, bool fCompressed) {
|
||||
EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
|
||||
return i2d_ECPrivateKey(pkey, &privkey);
|
||||
}
|
||||
|
||||
bool SetPrivKey(const unsigned char* privkey, size_t size, bool fSkipCheck=false) {
|
||||
if (d2i_ECPrivateKey(&pkey, &privkey, size)) {
|
||||
if(fSkipCheck)
|
||||
return true;
|
||||
|
||||
// d2i_ECPrivateKey returns true if parsing succeeds.
|
||||
// This doesn't necessarily mean the key is valid.
|
||||
if (EC_KEY_check_key(pkey))
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
void GetPubKey(CPubKey &pubkey, bool fCompressed) {
|
||||
EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
|
||||
int nSize = i2o_ECPublicKey(pkey, NULL);
|
||||
assert(nSize);
|
||||
assert(nSize <= 65);
|
||||
unsigned char c[65];
|
||||
unsigned char *pbegin = c;
|
||||
int nSize2 = i2o_ECPublicKey(pkey, &pbegin);
|
||||
assert(nSize == nSize2);
|
||||
pubkey.Set(&c[0], &c[nSize]);
|
||||
}
|
||||
|
||||
bool SetPubKey(const CPubKey &pubkey) {
|
||||
const unsigned char* pbegin = pubkey.begin();
|
||||
return o2i_ECPublicKey(&pkey, &pbegin, pubkey.size()) != NULL;
|
||||
}
|
||||
|
||||
bool Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool lowS) {
|
||||
vchSig.clear();
|
||||
ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
|
||||
if (sig == NULL)
|
||||
return false;
|
||||
BN_CTX *ctx = BN_CTX_new();
|
||||
BN_CTX_start(ctx);
|
||||
const EC_GROUP *group = EC_KEY_get0_group(pkey);
|
||||
BIGNUM *order = BN_CTX_get(ctx);
|
||||
BIGNUM *halforder = BN_CTX_get(ctx);
|
||||
EC_GROUP_get_order(group, order, ctx);
|
||||
BN_rshift1(halforder, order);
|
||||
if (lowS && BN_cmp(sig->s, halforder) > 0) {
|
||||
// enforce low S values, by negating the value (modulo the order) if above order/2.
|
||||
BN_sub(sig->s, order, sig->s);
|
||||
}
|
||||
BN_CTX_end(ctx);
|
||||
BN_CTX_free(ctx);
|
||||
unsigned int nSize = ECDSA_size(pkey);
|
||||
vchSig.resize(nSize); // Make sure it is big enough
|
||||
unsigned char *pos = &vchSig[0];
|
||||
nSize = i2d_ECDSA_SIG(sig, &pos);
|
||||
ECDSA_SIG_free(sig);
|
||||
vchSig.resize(nSize); // Shrink to fit actual size
|
||||
return true;
|
||||
}
|
||||
|
||||
bool Verify(const 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 SignCompact(const uint256 &hash, unsigned char *p64, int &rec) {
|
||||
bool fOk = false;
|
||||
ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
|
||||
if (sig==NULL)
|
||||
return false;
|
||||
memset(p64, 0, 64);
|
||||
int nBitsR = BN_num_bits(sig->r);
|
||||
int nBitsS = BN_num_bits(sig->s);
|
||||
if (nBitsR <= 256 && nBitsS <= 256) {
|
||||
CPubKey pubkey;
|
||||
GetPubKey(pubkey, true);
|
||||
for (int i=0; i<4; i++) {
|
||||
CECKey keyRec;
|
||||
if (ECDSA_SIG_recover_key_GFp(keyRec.pkey, sig, (unsigned char*)&hash, sizeof(hash), i, 1) == 1) {
|
||||
CPubKey pubkeyRec;
|
||||
keyRec.GetPubKey(pubkeyRec, true);
|
||||
if (pubkeyRec == pubkey) {
|
||||
rec = i;
|
||||
fOk = true;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
assert(fOk);
|
||||
BN_bn2bin(sig->r,&p64[32-(nBitsR+7)/8]);
|
||||
BN_bn2bin(sig->s,&p64[64-(nBitsS+7)/8]);
|
||||
}
|
||||
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 Recover(const uint256 &hash, const unsigned char *p64, int rec)
|
||||
{
|
||||
if (rec<0 || rec>=3)
|
||||
return false;
|
||||
ECDSA_SIG *sig = ECDSA_SIG_new();
|
||||
BN_bin2bn(&p64[0], 32, sig->r);
|
||||
BN_bin2bn(&p64[32], 32, sig->s);
|
||||
bool ret = ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), rec, 0) == 1;
|
||||
ECDSA_SIG_free(sig);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static bool TweakSecret(unsigned char vchSecretOut[32], const unsigned char vchSecretIn[32], const unsigned char vchTweak[32])
|
||||
{
|
||||
bool ret = true;
|
||||
BN_CTX *ctx = BN_CTX_new();
|
||||
BN_CTX_start(ctx);
|
||||
BIGNUM *bnSecret = BN_CTX_get(ctx);
|
||||
BIGNUM *bnTweak = BN_CTX_get(ctx);
|
||||
BIGNUM *bnOrder = BN_CTX_get(ctx);
|
||||
EC_GROUP *group = EC_GROUP_new_by_curve_name(NID_secp256k1);
|
||||
EC_GROUP_get_order(group, bnOrder, ctx); // what a grossly inefficient way to get the (constant) group order...
|
||||
BN_bin2bn(vchTweak, 32, bnTweak);
|
||||
if (BN_cmp(bnTweak, bnOrder) >= 0)
|
||||
ret = false; // extremely unlikely
|
||||
BN_bin2bn(vchSecretIn, 32, bnSecret);
|
||||
BN_add(bnSecret, bnSecret, bnTweak);
|
||||
BN_nnmod(bnSecret, bnSecret, bnOrder, ctx);
|
||||
if (BN_is_zero(bnSecret))
|
||||
ret = false; // ridiculously unlikely
|
||||
int nBits = BN_num_bits(bnSecret);
|
||||
memset(vchSecretOut, 0, 32);
|
||||
BN_bn2bin(bnSecret, &vchSecretOut[32-(nBits+7)/8]);
|
||||
EC_GROUP_free(group);
|
||||
BN_CTX_end(ctx);
|
||||
BN_CTX_free(ctx);
|
||||
return ret;
|
||||
}
|
||||
|
||||
bool TweakPublic(const unsigned char vchTweak[32]) {
|
||||
bool ret = true;
|
||||
BN_CTX *ctx = BN_CTX_new();
|
||||
BN_CTX_start(ctx);
|
||||
BIGNUM *bnTweak = BN_CTX_get(ctx);
|
||||
BIGNUM *bnOrder = BN_CTX_get(ctx);
|
||||
BIGNUM *bnOne = BN_CTX_get(ctx);
|
||||
const EC_GROUP *group = EC_KEY_get0_group(pkey);
|
||||
EC_GROUP_get_order(group, bnOrder, ctx); // what a grossly inefficient way to get the (constant) group order...
|
||||
BN_bin2bn(vchTweak, 32, bnTweak);
|
||||
if (BN_cmp(bnTweak, bnOrder) >= 0)
|
||||
ret = false; // extremely unlikely
|
||||
EC_POINT *point = EC_POINT_dup(EC_KEY_get0_public_key(pkey), group);
|
||||
BN_one(bnOne);
|
||||
EC_POINT_mul(group, point, bnTweak, point, bnOne, ctx);
|
||||
if (EC_POINT_is_at_infinity(group, point))
|
||||
ret = false; // ridiculously unlikely
|
||||
EC_KEY_set_public_key(pkey, point);
|
||||
EC_POINT_free(point);
|
||||
BN_CTX_end(ctx);
|
||||
BN_CTX_free(ctx);
|
||||
return ret;
|
||||
}
|
||||
};
|
||||
|
||||
#endif
|
||||
|
||||
int CompareBigEndian(const unsigned char *c1, size_t c1len, const unsigned char *c2, size_t c2len) {
|
||||
@ -455,19 +133,21 @@ CPrivKey CKey::GetPrivKey() const {
|
||||
|
||||
CPubKey CKey::GetPubKey() const {
|
||||
assert(fValid);
|
||||
CPubKey pubkey;
|
||||
CPubKey result;
|
||||
#ifdef USE_SECP256K1
|
||||
int clen = 65;
|
||||
int ret = secp256k1_ecdsa_pubkey_create((unsigned char*)pubkey.begin(), &clen, begin(), fCompressed);
|
||||
int ret = secp256k1_ecdsa_pubkey_create((unsigned char*)result.begin(), &clen, begin(), fCompressed);
|
||||
assert((int)result.size() == clen);
|
||||
assert(ret);
|
||||
assert(pubkey.IsValid());
|
||||
assert((int)pubkey.size() == clen);
|
||||
#else
|
||||
std::vector<unsigned char> pubkey;
|
||||
CECKey key;
|
||||
key.SetSecretBytes(vch);
|
||||
key.GetPubKey(pubkey, fCompressed);
|
||||
result.Set(pubkey.begin(), pubkey.end());
|
||||
#endif
|
||||
return pubkey;
|
||||
assert(result.IsValid());
|
||||
return result;
|
||||
}
|
||||
|
||||
bool CKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool lowS) const {
|
||||
@ -544,7 +224,7 @@ bool CPubKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchS
|
||||
return false;
|
||||
#else
|
||||
CECKey key;
|
||||
if (!key.SetPubKey(*this))
|
||||
if (!key.SetPubKey(begin(), size()))
|
||||
return false;
|
||||
if (!key.Verify(hash, vchSig))
|
||||
return false;
|
||||
@ -566,7 +246,9 @@ bool CPubKey::RecoverCompact(const uint256 &hash, const std::vector<unsigned cha
|
||||
CECKey key;
|
||||
if (!key.Recover(hash, &vchSig[1], recid))
|
||||
return false;
|
||||
key.GetPubKey(*this, fComp);
|
||||
std::vector<unsigned char> pubkey;
|
||||
key.GetPubKey(pubkey, fComp);
|
||||
Set(pubkey.begin(), pubkey.end());
|
||||
#endif
|
||||
return true;
|
||||
}
|
||||
@ -579,7 +261,7 @@ bool CPubKey::IsFullyValid() const {
|
||||
return false;
|
||||
#else
|
||||
CECKey key;
|
||||
if (!key.SetPubKey(*this))
|
||||
if (!key.SetPubKey(begin(), size()))
|
||||
return false;
|
||||
#endif
|
||||
return true;
|
||||
@ -595,9 +277,11 @@ bool CPubKey::Decompress() {
|
||||
assert(clen == (int)size());
|
||||
#else
|
||||
CECKey key;
|
||||
if (!key.SetPubKey(*this))
|
||||
if (!key.SetPubKey(begin(), size()))
|
||||
return false;
|
||||
key.GetPubKey(*this, false);
|
||||
std::vector<unsigned char> pubkey;
|
||||
key.GetPubKey(pubkey, false);
|
||||
Set(pubkey.begin(), pubkey.end());
|
||||
#endif
|
||||
return true;
|
||||
}
|
||||
@ -652,9 +336,11 @@ bool CPubKey::Derive(CPubKey& pubkeyChild, unsigned char ccChild[32], unsigned i
|
||||
bool ret = secp256k1_ecdsa_pubkey_tweak_add((unsigned char*)pubkeyChild.begin(), pubkeyChild.size(), out);
|
||||
#else
|
||||
CECKey key;
|
||||
bool ret = key.SetPubKey(*this);
|
||||
bool ret = key.SetPubKey(begin(), size());
|
||||
ret &= key.TweakPublic(out);
|
||||
key.GetPubKey(pubkeyChild, true);
|
||||
std::vector<unsigned char> pubkey;
|
||||
key.GetPubKey(pubkey, true);
|
||||
pubkeyChild.Set(pubkey.begin(), pubkey.end());
|
||||
#endif
|
||||
return ret;
|
||||
}
|
||||
@ -739,12 +425,6 @@ bool ECC_InitSanityCheck() {
|
||||
#ifdef USE_SECP256K1
|
||||
return true;
|
||||
#else
|
||||
EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
|
||||
if(pkey == NULL)
|
||||
return false;
|
||||
EC_KEY_free(pkey);
|
||||
|
||||
// TODO Is there more EC functionality that could be missing?
|
||||
return true;
|
||||
return CECKey::SanityCheck();
|
||||
#endif
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user