int secp256k1_ecdsa_sign(const unsigned char *message, int messagelen, unsigned char *signature, int *signaturelen, const unsigned char *seckey, const unsigned char *nonce) {
secp256k1_num_t sec, non, msg;
secp256k1_num_init(&sec);
secp256k1_num_init(&non);
secp256k1_num_init(&msg);
secp256k1_num_set_bin(&sec, seckey, 32);
secp256k1_num_set_bin(&non, nonce, 32);
secp256k1_num_set_bin(&msg, message, messagelen);
int ret = !secp256k1_num_is_zero(&non) &&
(secp256k1_num_cmp(&non, &secp256k1_ge_consts->order) < 0);
secp256k1_ecdsa_sig_t sig;
secp256k1_ecdsa_sig_init(&sig);
if (ret) {
ret = secp256k1_ecdsa_sig_sign(&sig, &sec, &msg, &non, NULL);
}
if (ret) {
secp256k1_ecdsa_sig_serialize(signature, signaturelen, &sig);
}
secp256k1_ecdsa_sig_free(&sig);
secp256k1_num_clear(&msg);
secp256k1_num_clear(&non);
secp256k1_num_clear(&sec);
secp256k1_num_free(&msg);
secp256k1_num_free(&non);
secp256k1_num_free(&sec);
return ret;
}
int secp256k1_ecdsa_sign_compact(const unsigned char *message, int messagelen, unsigned char *sig64, const unsigned char *seckey, const unsigned char *nonce, int *recid) {
secp256k1_num_t sec, non, msg;
secp256k1_num_init(&sec);
secp256k1_num_init(&non);
secp256k1_num_init(&msg);
secp256k1_num_set_bin(&sec, seckey, 32);
secp256k1_num_set_bin(&non, nonce, 32);
secp256k1_num_set_bin(&msg, message, messagelen);
int ret = !secp256k1_num_is_zero(&non) &&
(secp256k1_num_cmp(&non, &secp256k1_ge_consts->order) < 0);
secp256k1_ecdsa_sig_t sig;
secp256k1_ecdsa_sig_init(&sig);
if (ret) {
ret = secp256k1_ecdsa_sig_sign(&sig, &sec, &msg, &non, recid);
}
if (ret) {
secp256k1_num_get_bin(sig64, 32, &sig.r);
secp256k1_num_get_bin(sig64 + 32, 32, &sig.s);
}
secp256k1_ecdsa_sig_free(&sig);
secp256k1_num_clear(&msg);
secp256k1_num_clear(&non);
secp256k1_num_clear(&sec);
secp256k1_num_free(&msg);
secp256k1_num_free(&non);
secp256k1_num_free(&sec);
return ret;
}
int secp256k1_ecdsa_verify(const unsigned char *msg, int msglen, const unsigned char *sig, int siglen, const unsigned char *pubkey, int pubkeylen) {
int ret = -3;
secp256k1_num_t m;
secp256k1_num_init(&m);
secp256k1_ecdsa_sig_t s;
secp256k1_ecdsa_sig_init(&s);
secp256k1_ge_t q;
secp256k1_num_set_bin(&m, msg, msglen);
if (!secp256k1_ecdsa_pubkey_parse(&q, pubkey, pubkeylen)) {
ret = -1;
goto end;
}
if (!secp256k1_ecdsa_sig_parse(&s, sig, siglen)) {
ret = -2;
goto end;
}
if (!secp256k1_ecdsa_sig_verify(&s, &q, &m)) {
ret = 0;
goto end;
}
ret = 1;
end:
secp256k1_ecdsa_sig_free(&s);
secp256k1_num_free(&m);
return ret;
}
int secp256k1_ecdsa_recover_compact(const unsigned char *msg, int msglen, const unsigned char *sig64, unsigned char *pubkey, int *pubkeylen, int compressed, int recid) {
DEBUG_CHECK(secp256k1_ecmult_consts != NULL);
DEBUG_CHECK(msg != NULL);
DEBUG_CHECK(msglen <= 32);
DEBUG_CHECK(sig64 != NULL);
DEBUG_CHECK(pubkey != NULL);
DEBUG_CHECK(pubkeylen != NULL);
DEBUG_CHECK(recid >= 0 && recid <= 3);
int ret = 0;
secp256k1_num_t m;
secp256k1_num_init(&m);
secp256k1_ecdsa_sig_t sig;
secp256k1_ecdsa_sig_init(&sig);
secp256k1_num_set_bin(&sig.r, sig64, 32);
secp256k1_num_set_bin(&sig.s, sig64 + 32, 32);
secp256k1_num_set_bin(&m, msg, msglen);
secp256k1_ge_t q;
if (secp256k1_ecdsa_sig_recover(&sig, &q, &m, recid)) {
secp256k1_ecdsa_pubkey_serialize(&q, pubkey, pubkeylen, compressed);
ret = 1;
}
secp256k1_ecdsa_sig_free(&sig);
secp256k1_num_free(&m);
return ret;
}
void test_ecdsa_openssl() {
const secp256k1_ge_consts_t *c = secp256k1_ge_consts;
secp256k1_num_t key, msg;
secp256k1_num_init(&msg);
unsigned char message[32];
secp256k1_rand256_test(message);
secp256k1_num_set_bin(&msg, message, 32);
secp256k1_num_init(&key);
random_num_order_test(&key);
secp256k1_gej_t qj;
secp256k1_ecmult_gen(&qj, &key);
secp256k1_ge_t q;
secp256k1_ge_set_gej(&q, &qj);
EC_KEY *ec_key = get_openssl_key(&key);
assert(ec_key);
unsigned char signature[80];
int sigsize = 80;
assert(ECDSA_sign(0, message, sizeof(message), signature, &sigsize, ec_key));
secp256k1_ecdsa_sig_t sig;
secp256k1_ecdsa_sig_init(&sig);
assert(secp256k1_ecdsa_sig_parse(&sig, signature, sigsize));
assert(secp256k1_ecdsa_sig_verify(&sig, &q, &msg));
secp256k1_num_inc(&sig.r);
assert(!secp256k1_ecdsa_sig_verify(&sig, &q, &msg));
random_sign(&sig, &key, &msg, NULL);
sigsize = 80;
assert(secp256k1_ecdsa_sig_serialize(signature, &sigsize, &sig));
assert(ECDSA_verify(0, message, sizeof(message), signature, sigsize, ec_key) == 1);
secp256k1_ecdsa_sig_free(&sig);
EC_KEY_free(ec_key);
secp256k1_num_free(&key);
secp256k1_num_free(&msg);
}
int secp256k1_ecdsa_recover_compact(const unsigned char *msg, int msglen, const unsigned char *sig64, unsigned char *pubkey, int *pubkeylen, int compressed, int recid) {
int ret = 0;
secp256k1_num_t m;
secp256k1_num_init(&m);
secp256k1_ecdsa_sig_t sig;
secp256k1_ecdsa_sig_init(&sig);
secp256k1_num_set_bin(&sig.r, sig64, 32);
secp256k1_num_set_bin(&sig.s, sig64 + 32, 32);
secp256k1_num_set_bin(&m, msg, msglen);
secp256k1_ge_t q;
if (secp256k1_ecdsa_sig_recover(&sig, &q, &m, recid)) {
secp256k1_ecdsa_pubkey_serialize(&q, pubkey, pubkeylen, compressed);
ret = 1;
}
secp256k1_ecdsa_sig_free(&sig);
secp256k1_num_free(&m);
return ret;
}
void test_ecdsa_sign_verify() {
const secp256k1_ge_consts_t *c = secp256k1_ge_consts;
secp256k1_num_t msg, key;
secp256k1_num_init(&msg);
random_num_order_test(&msg);
secp256k1_num_init(&key);
random_num_order_test(&key);
secp256k1_gej_t pubj; secp256k1_ecmult_gen(&pubj, &key);
secp256k1_ge_t pub; secp256k1_ge_set_gej(&pub, &pubj);
secp256k1_ecdsa_sig_t sig;
secp256k1_ecdsa_sig_init(&sig);
random_sign(&sig, &key, &msg, NULL);
assert(secp256k1_ecdsa_sig_verify(&sig, &pub, &msg));
secp256k1_num_inc(&msg);
assert(!secp256k1_ecdsa_sig_verify(&sig, &pub, &msg));
secp256k1_ecdsa_sig_free(&sig);
secp256k1_num_free(&msg);
secp256k1_num_free(&key);
}
int main() {
secp256k1_fe_start();
secp256k1_ge_start();
secp256k1_ecmult_start();
secp256k1_fe_t x;
const secp256k1_num_t *order = &secp256k1_ge_consts->order;
secp256k1_num_t r, s, m;
secp256k1_num_init(&r);
secp256k1_num_init(&s);
secp256k1_num_init(&m);
secp256k1_ecdsa_sig_t sig;
secp256k1_ecdsa_sig_init(&sig);
secp256k1_fe_set_hex(&x, "a357ae915c4a65281309edf20504740f0eb3343990216b4f81063cb65f2f7e0f", 64);
int cnt = 0;
int good = 0;
for (int i=0; i<1000000; i++) {
random_num_order(&r);
random_num_order(&s);
random_num_order(&m);
secp256k1_ecdsa_sig_set_rs(&sig, &r, &s);
secp256k1_ge_t pubkey; secp256k1_ge_set_xo(&pubkey, &x, 1);
if (secp256k1_ge_is_valid(&pubkey)) {
cnt++;
good += secp256k1_ecdsa_sig_verify(&sig, &pubkey, &m);
}
}
printf("%i/%i\n", good, cnt);
secp256k1_num_free(&r);
secp256k1_num_free(&s);
secp256k1_num_free(&m);
secp256k1_ecdsa_sig_free(&sig);
secp256k1_ecmult_stop();
secp256k1_ge_stop();
secp256k1_fe_stop();
return 0;
}