Update libsecp256k1

This commit is contained in:
Gustav Simonsson
2015-09-28 17:46:17 +02:00
parent 7977e87ce1
commit 1d20b0247c
86 changed files with 6279 additions and 2772 deletions

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include_HEADERS += include/secp256k1_ecdh.h
noinst_HEADERS += src/modules/ecdh/main_impl.h
noinst_HEADERS += src/modules/ecdh/tests_impl.h
if USE_BENCHMARK
noinst_PROGRAMS += bench_ecdh
bench_ecdh_SOURCES = src/bench_ecdh.c
bench_ecdh_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_ecdh_LDFLAGS = -static
endif

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/**********************************************************************
* Copyright (c) 2015 Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_ECDH_MAIN_
#define _SECP256K1_MODULE_ECDH_MAIN_
#include "include/secp256k1_ecdh.h"
#include "ecmult_const_impl.h"
int secp256k1_ecdh(const secp256k1_context* ctx, unsigned char *result, const secp256k1_pubkey *point, const unsigned char *scalar) {
int ret = 0;
int overflow = 0;
secp256k1_gej res;
secp256k1_ge pt;
secp256k1_scalar s;
ARG_CHECK(result != NULL);
ARG_CHECK(point != NULL);
ARG_CHECK(scalar != NULL);
(void)ctx;
secp256k1_pubkey_load(ctx, &pt, point);
secp256k1_scalar_set_b32(&s, scalar, &overflow);
if (overflow || secp256k1_scalar_is_zero(&s)) {
ret = 0;
} else {
unsigned char x[32];
unsigned char y[1];
secp256k1_sha256_t sha;
secp256k1_ecmult_const(&res, &pt, &s);
secp256k1_ge_set_gej(&pt, &res);
/* Compute a hash of the point in compressed form
* Note we cannot use secp256k1_eckey_pubkey_serialize here since it does not
* expect its output to be secret and has a timing sidechannel. */
secp256k1_fe_normalize(&pt.x);
secp256k1_fe_normalize(&pt.y);
secp256k1_fe_get_b32(x, &pt.x);
y[0] = 0x02 | secp256k1_fe_is_odd(&pt.y);
secp256k1_sha256_initialize(&sha);
secp256k1_sha256_write(&sha, y, sizeof(y));
secp256k1_sha256_write(&sha, x, sizeof(x));
secp256k1_sha256_finalize(&sha, result);
ret = 1;
}
secp256k1_scalar_clear(&s);
return ret;
}
#endif

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/**********************************************************************
* Copyright (c) 2015 Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_ECDH_TESTS_
#define _SECP256K1_MODULE_ECDH_TESTS_
void test_ecdh_generator_basepoint(void) {
unsigned char s_one[32] = { 0 };
secp256k1_pubkey point[2];
int i;
s_one[31] = 1;
/* Check against pubkey creation when the basepoint is the generator */
for (i = 0; i < 100; ++i) {
secp256k1_sha256_t sha;
unsigned char s_b32[32];
unsigned char output_ecdh[32];
unsigned char output_ser[32];
unsigned char point_ser[33];
size_t point_ser_len = sizeof(point_ser);
secp256k1_scalar s;
random_scalar_order(&s);
secp256k1_scalar_get_b32(s_b32, &s);
/* compute using ECDH function */
CHECK(secp256k1_ec_pubkey_create(ctx, &point[0], s_one) == 1);
CHECK(secp256k1_ecdh(ctx, output_ecdh, &point[0], s_b32) == 1);
/* compute "explicitly" */
CHECK(secp256k1_ec_pubkey_create(ctx, &point[1], s_b32) == 1);
CHECK(secp256k1_ec_pubkey_serialize(ctx, point_ser, &point_ser_len, &point[1], SECP256K1_EC_COMPRESSED) == 1);
CHECK(point_ser_len == sizeof(point_ser));
secp256k1_sha256_initialize(&sha);
secp256k1_sha256_write(&sha, point_ser, point_ser_len);
secp256k1_sha256_finalize(&sha, output_ser);
/* compare */
CHECK(memcmp(output_ecdh, output_ser, sizeof(output_ser)) == 0);
}
}
void test_bad_scalar(void) {
unsigned char s_zero[32] = { 0 };
unsigned char s_overflow[32] = {
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
0xba, 0xae, 0xdc, 0xe6, 0xaf, 0x48, 0xa0, 0x3b,
0xbf, 0xd2, 0x5e, 0x8c, 0xd0, 0x36, 0x41, 0x41
};
unsigned char s_rand[32] = { 0 };
unsigned char output[32];
secp256k1_scalar rand;
secp256k1_pubkey point;
/* Create random point */
random_scalar_order(&rand);
secp256k1_scalar_get_b32(s_rand, &rand);
CHECK(secp256k1_ec_pubkey_create(ctx, &point, s_rand) == 1);
/* Try to multiply it by bad values */
CHECK(secp256k1_ecdh(ctx, output, &point, s_zero) == 0);
CHECK(secp256k1_ecdh(ctx, output, &point, s_overflow) == 0);
/* ...and a good one */
s_overflow[31] -= 1;
CHECK(secp256k1_ecdh(ctx, output, &point, s_overflow) == 1);
}
void run_ecdh_tests(void) {
test_ecdh_generator_basepoint();
test_bad_scalar();
}
#endif

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include_HEADERS += include/secp256k1_recovery.h
noinst_HEADERS += src/modules/recovery/main_impl.h
noinst_HEADERS += src/modules/recovery/tests_impl.h
if USE_BENCHMARK
noinst_PROGRAMS += bench_recover
bench_recover_SOURCES = src/bench_recover.c
bench_recover_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_recover_LDFLAGS = -static
endif

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/**********************************************************************
* Copyright (c) 2013-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_RECOVERY_MAIN_
#define _SECP256K1_MODULE_RECOVERY_MAIN_
#include "include/secp256k1_recovery.h"
static void secp256k1_ecdsa_recoverable_signature_load(const secp256k1_context* ctx, secp256k1_scalar* r, secp256k1_scalar* s, int* recid, const secp256k1_ecdsa_recoverable_signature* sig) {
(void)ctx;
if (sizeof(secp256k1_scalar) == 32) {
/* When the secp256k1_scalar type is exactly 32 byte, use its
* representation inside secp256k1_ecdsa_signature, as conversion is very fast.
* Note that secp256k1_ecdsa_signature_save must use the same representation. */
memcpy(r, &sig->data[0], 32);
memcpy(s, &sig->data[32], 32);
} else {
secp256k1_scalar_set_b32(r, &sig->data[0], NULL);
secp256k1_scalar_set_b32(s, &sig->data[32], NULL);
}
*recid = sig->data[64];
}
static void secp256k1_ecdsa_recoverable_signature_save(secp256k1_ecdsa_recoverable_signature* sig, const secp256k1_scalar* r, const secp256k1_scalar* s, int recid) {
if (sizeof(secp256k1_scalar) == 32) {
memcpy(&sig->data[0], r, 32);
memcpy(&sig->data[32], s, 32);
} else {
secp256k1_scalar_get_b32(&sig->data[0], r);
secp256k1_scalar_get_b32(&sig->data[32], s);
}
sig->data[64] = recid;
}
int secp256k1_ecdsa_recoverable_signature_parse_compact(const secp256k1_context* ctx, secp256k1_ecdsa_recoverable_signature* sig, const unsigned char *input64, int recid) {
secp256k1_scalar r, s;
int ret = 1;
int overflow = 0;
(void)ctx;
ARG_CHECK(sig != NULL);
ARG_CHECK(input64 != NULL);
ARG_CHECK(recid >= 0 && recid <= 3);
secp256k1_scalar_set_b32(&r, &input64[0], &overflow);
ret &= !overflow;
secp256k1_scalar_set_b32(&s, &input64[32], &overflow);
ret &= !overflow;
if (ret) {
secp256k1_ecdsa_recoverable_signature_save(sig, &r, &s, recid);
} else {
memset(sig, 0, sizeof(*sig));
}
return ret;
}
int secp256k1_ecdsa_recoverable_signature_serialize_compact(const secp256k1_context* ctx, unsigned char *output64, int *recid, const secp256k1_ecdsa_recoverable_signature* sig) {
secp256k1_scalar r, s;
(void)ctx;
ARG_CHECK(output64 != NULL);
ARG_CHECK(sig != NULL);
secp256k1_ecdsa_recoverable_signature_load(ctx, &r, &s, recid, sig);
secp256k1_scalar_get_b32(&output64[0], &r);
secp256k1_scalar_get_b32(&output64[32], &s);
return 1;
}
int secp256k1_ecdsa_recoverable_signature_convert(const secp256k1_context* ctx, secp256k1_ecdsa_signature* sig, const secp256k1_ecdsa_recoverable_signature* sigin) {
secp256k1_scalar r, s;
int recid;
(void)ctx;
ARG_CHECK(sig != NULL);
ARG_CHECK(sigin != NULL);
secp256k1_ecdsa_recoverable_signature_load(ctx, &r, &s, &recid, sigin);
secp256k1_ecdsa_signature_save(sig, &r, &s);
return 1;
}
int secp256k1_ecdsa_sign_recoverable(const secp256k1_context* ctx, secp256k1_ecdsa_recoverable_signature *signature, const unsigned char *msg32, const unsigned char *seckey, secp256k1_nonce_function noncefp, const void* noncedata) {
secp256k1_scalar r, s;
secp256k1_scalar sec, non, msg;
int recid;
int ret = 0;
int overflow = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(signature != NULL);
ARG_CHECK(seckey != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
secp256k1_scalar_set_b32(&sec, seckey, &overflow);
/* Fail if the secret key is invalid. */
if (!overflow && !secp256k1_scalar_is_zero(&sec)) {
unsigned int count = 0;
secp256k1_scalar_set_b32(&msg, msg32, NULL);
while (1) {
unsigned char nonce32[32];
ret = noncefp(nonce32, seckey, msg32, NULL, (void*)noncedata, count);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&non, nonce32, &overflow);
memset(nonce32, 0, 32);
if (!secp256k1_scalar_is_zero(&non) && !overflow) {
if (secp256k1_ecdsa_sig_sign(&ctx->ecmult_gen_ctx, &r, &s, &sec, &msg, &non, &recid)) {
break;
}
}
count++;
}
secp256k1_scalar_clear(&msg);
secp256k1_scalar_clear(&non);
secp256k1_scalar_clear(&sec);
}
if (ret) {
secp256k1_ecdsa_recoverable_signature_save(signature, &r, &s, recid);
} else {
memset(signature, 0, sizeof(*signature));
}
return ret;
}
int secp256k1_ecdsa_recover(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const secp256k1_ecdsa_recoverable_signature *signature, const unsigned char *msg32) {
secp256k1_ge q;
secp256k1_scalar r, s;
secp256k1_scalar m;
int recid;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(signature != NULL);
ARG_CHECK(pubkey != NULL);
secp256k1_ecdsa_recoverable_signature_load(ctx, &r, &s, &recid, signature);
ARG_CHECK(recid >= 0 && recid < 4);
secp256k1_scalar_set_b32(&m, msg32, NULL);
if (secp256k1_ecdsa_sig_recover(&ctx->ecmult_ctx, &r, &s, &q, &m, recid)) {
secp256k1_pubkey_save(pubkey, &q);
return 1;
} else {
memset(pubkey, 0, sizeof(*pubkey));
return 0;
}
}
#endif

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/**********************************************************************
* Copyright (c) 2013-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef _SECP256K1_MODULE_RECOVERY_TESTS_
#define _SECP256K1_MODULE_RECOVERY_TESTS_
void test_ecdsa_recovery_end_to_end(void) {
unsigned char extra[32] = {0x00};
unsigned char privkey[32];
unsigned char message[32];
secp256k1_ecdsa_signature signature[5];
secp256k1_ecdsa_recoverable_signature rsignature[5];
unsigned char sig[74];
secp256k1_pubkey pubkey;
secp256k1_pubkey recpubkey;
int recid = 0;
/* Generate a random key and message. */
{
secp256k1_scalar msg, key;
random_scalar_order_test(&msg);
random_scalar_order_test(&key);
secp256k1_scalar_get_b32(privkey, &key);
secp256k1_scalar_get_b32(message, &msg);
}
/* Construct and verify corresponding public key. */
CHECK(secp256k1_ec_seckey_verify(ctx, privkey) == 1);
CHECK(secp256k1_ec_pubkey_create(ctx, &pubkey, privkey) == 1);
/* Serialize/parse compact and verify/recover. */
extra[0] = 0;
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[0], message, privkey, NULL, NULL) == 1);
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[4], message, privkey, NULL, NULL) == 1);
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[1], message, privkey, NULL, extra) == 1);
extra[31] = 1;
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[2], message, privkey, NULL, extra) == 1);
extra[31] = 0;
extra[0] = 1;
CHECK(secp256k1_ecdsa_sign_recoverable(ctx, &rsignature[3], message, privkey, NULL, extra) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_serialize_compact(ctx, sig, &recid, &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_convert(ctx, &signature[4], &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &signature[4], message, &pubkey) == 1);
memset(&rsignature[4], 0, sizeof(rsignature[4]));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsignature[4], sig, recid) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_convert(ctx, &signature[4], &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &signature[4], message, &pubkey) == 1);
/* Parse compact (with recovery id) and recover. */
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsignature[4], sig, recid) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &recpubkey, &rsignature[4], message) == 1);
CHECK(memcmp(&pubkey, &recpubkey, sizeof(pubkey)) == 0);
/* Serialize/destroy/parse signature and verify again. */
CHECK(secp256k1_ecdsa_recoverable_signature_serialize_compact(ctx, sig, &recid, &rsignature[4]) == 1);
sig[secp256k1_rand32() % 64] += 1 + (secp256k1_rand32() % 255);
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsignature[4], sig, recid) == 1);
CHECK(secp256k1_ecdsa_recoverable_signature_convert(ctx, &signature[4], &rsignature[4]) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &signature[4], message, &pubkey) == 0);
/* Recover again */
CHECK(secp256k1_ecdsa_recover(ctx, &recpubkey, &rsignature[4], message) == 0 ||
memcmp(&pubkey, &recpubkey, sizeof(pubkey)) != 0);
}
/* Tests several edge cases. */
void test_ecdsa_recovery_edge_cases(void) {
const unsigned char msg32[32] = {
'T', 'h', 'i', 's', ' ', 'i', 's', ' ',
'a', ' ', 'v', 'e', 'r', 'y', ' ', 's',
'e', 'c', 'r', 'e', 't', ' ', 'm', 'e',
's', 's', 'a', 'g', 'e', '.', '.', '.'
};
const unsigned char sig64[64] = {
/* Generated by signing the above message with nonce 'This is the nonce we will use...'
* and secret key 0 (which is not valid), resulting in recid 0. */
0x67, 0xCB, 0x28, 0x5F, 0x9C, 0xD1, 0x94, 0xE8,
0x40, 0xD6, 0x29, 0x39, 0x7A, 0xF5, 0x56, 0x96,
0x62, 0xFD, 0xE4, 0x46, 0x49, 0x99, 0x59, 0x63,
0x17, 0x9A, 0x7D, 0xD1, 0x7B, 0xD2, 0x35, 0x32,
0x4B, 0x1B, 0x7D, 0xF3, 0x4C, 0xE1, 0xF6, 0x8E,
0x69, 0x4F, 0xF6, 0xF1, 0x1A, 0xC7, 0x51, 0xDD,
0x7D, 0xD7, 0x3E, 0x38, 0x7E, 0xE4, 0xFC, 0x86,
0x6E, 0x1B, 0xE8, 0xEC, 0xC7, 0xDD, 0x95, 0x57
};
secp256k1_pubkey pubkey;
/* signature (r,s) = (4,4), which can be recovered with all 4 recids. */
const unsigned char sigb64[64] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
};
secp256k1_pubkey pubkeyb;
secp256k1_ecdsa_recoverable_signature rsig;
secp256k1_ecdsa_signature sig;
int recid;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 0));
CHECK(!secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 1));
CHECK(secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 2));
CHECK(!secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sig64, 3));
CHECK(!secp256k1_ecdsa_recover(ctx, &pubkey, &rsig, msg32));
for (recid = 0; recid < 4; recid++) {
int i;
int recid2;
/* (4,4) encoded in DER. */
unsigned char sigbder[8] = {0x30, 0x06, 0x02, 0x01, 0x04, 0x02, 0x01, 0x04};
unsigned char sigcder_zr[7] = {0x30, 0x05, 0x02, 0x00, 0x02, 0x01, 0x01};
unsigned char sigcder_zs[7] = {0x30, 0x05, 0x02, 0x01, 0x01, 0x02, 0x00};
unsigned char sigbderalt1[39] = {
0x30, 0x25, 0x02, 0x20, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x04, 0x02, 0x01, 0x04,
};
unsigned char sigbderalt2[39] = {
0x30, 0x25, 0x02, 0x01, 0x04, 0x02, 0x20, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
};
unsigned char sigbderalt3[40] = {
0x30, 0x26, 0x02, 0x21, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x04, 0x02, 0x01, 0x04,
};
unsigned char sigbderalt4[40] = {
0x30, 0x26, 0x02, 0x01, 0x04, 0x02, 0x21, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
};
/* (order + r,4) encoded in DER. */
unsigned char sigbderlong[40] = {
0x30, 0x26, 0x02, 0x21, 0x00, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xBA, 0xAE, 0xDC,
0xE6, 0xAF, 0x48, 0xA0, 0x3B, 0xBF, 0xD2, 0x5E,
0x8C, 0xD0, 0x36, 0x41, 0x45, 0x02, 0x01, 0x04
};
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigb64, recid) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyb, &rsig, msg32) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
for (recid2 = 0; recid2 < 4; recid2++) {
secp256k1_pubkey pubkey2b;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigb64, recid2) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkey2b, &rsig, msg32) == 1);
/* Verifying with (order + r,4) should always fail. */
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderlong, sizeof(sigbderlong)) == 0);
}
/* DER parsing tests. */
/* Zero length r/s. */
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder_zr, sizeof(sigcder_zr)) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder_zs, sizeof(sigcder_zs)) == 0);
/* Leading zeros. */
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt1, sizeof(sigbderalt1)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt2, sizeof(sigbderalt2)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt3, sizeof(sigbderalt3)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt4, sizeof(sigbderalt4)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 1);
sigbderalt3[4] = 1;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt3, sizeof(sigbderalt3)) == 0);
sigbderalt4[7] = 1;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbderalt4, sizeof(sigbderalt4)) == 0);
/* Damage signature. */
sigbder[7]++;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 0);
sigbder[7]--;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, 6) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder) - 1) == 0);
for(i = 0; i < 8; i++) {
int c;
unsigned char orig = sigbder[i];
/*Try every single-byte change.*/
for (c = 0; c < 256; c++) {
if (c == orig ) {
continue;
}
sigbder[i] = c;
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigbder, sizeof(sigbder)) == 0 || secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyb) == 0);
}
sigbder[i] = orig;
}
}
/* Test r/s equal to zero */
{
/* (1,1) encoded in DER. */
unsigned char sigcder[8] = {0x30, 0x06, 0x02, 0x01, 0x01, 0x02, 0x01, 0x01};
unsigned char sigc64[64] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
};
secp256k1_pubkey pubkeyc;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigc64, 0) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyc, &rsig, msg32) == 1);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder, sizeof(sigcder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyc) == 1);
sigcder[4] = 0;
sigc64[31] = 0;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigc64, 0) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyb, &rsig, msg32) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder, sizeof(sigcder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyc) == 0);
sigcder[4] = 1;
sigcder[7] = 0;
sigc64[31] = 1;
sigc64[63] = 0;
CHECK(secp256k1_ecdsa_recoverable_signature_parse_compact(ctx, &rsig, sigc64, 0) == 1);
CHECK(secp256k1_ecdsa_recover(ctx, &pubkeyb, &rsig, msg32) == 0);
CHECK(secp256k1_ecdsa_signature_parse_der(ctx, &sig, sigcder, sizeof(sigcder)) == 1);
CHECK(secp256k1_ecdsa_verify(ctx, &sig, msg32, &pubkeyc) == 0);
}
}
void run_recovery_tests(void) {
int i;
for (i = 0; i < 64*count; i++) {
test_ecdsa_recovery_end_to_end();
}
test_ecdsa_recovery_edge_cases();
}
#endif

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include_HEADERS += include/secp256k1_schnorr.h
noinst_HEADERS += src/modules/schnorr/main_impl.h
noinst_HEADERS += src/modules/schnorr/schnorr.h
noinst_HEADERS += src/modules/schnorr/schnorr_impl.h
noinst_HEADERS += src/modules/schnorr/tests_impl.h
if USE_BENCHMARK
noinst_PROGRAMS += bench_schnorr_verify
bench_schnorr_verify_SOURCES = src/bench_schnorr_verify.c
bench_schnorr_verify_LDADD = libsecp256k1.la $(SECP_LIBS)
bench_schnorr_verify_LDFLAGS = -static
endif

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/**********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef SECP256K1_MODULE_SCHNORR_MAIN
#define SECP256K1_MODULE_SCHNORR_MAIN
#include "include/secp256k1_schnorr.h"
#include "modules/schnorr/schnorr_impl.h"
static void secp256k1_schnorr_msghash_sha256(unsigned char *h32, const unsigned char *r32, const unsigned char *msg32) {
secp256k1_sha256_t sha;
secp256k1_sha256_initialize(&sha);
secp256k1_sha256_write(&sha, r32, 32);
secp256k1_sha256_write(&sha, msg32, 32);
secp256k1_sha256_finalize(&sha, h32);
}
static const unsigned char secp256k1_schnorr_algo16[17] = "Schnorr+SHA256 ";
int secp256k1_schnorr_sign(const secp256k1_context* ctx, unsigned char *sig64, const unsigned char *msg32, const unsigned char *seckey, secp256k1_nonce_function noncefp, const void* noncedata) {
secp256k1_scalar sec, non;
int ret = 0;
int overflow = 0;
unsigned int count = 0;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(seckey != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
secp256k1_scalar_set_b32(&sec, seckey, NULL);
while (1) {
unsigned char nonce32[32];
ret = noncefp(nonce32, msg32, seckey, secp256k1_schnorr_algo16, (void*)noncedata, count);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&non, nonce32, &overflow);
memset(nonce32, 0, 32);
if (!secp256k1_scalar_is_zero(&non) && !overflow) {
if (secp256k1_schnorr_sig_sign(&ctx->ecmult_gen_ctx, sig64, &sec, &non, NULL, secp256k1_schnorr_msghash_sha256, msg32)) {
break;
}
}
count++;
}
if (!ret) {
memset(sig64, 0, 64);
}
secp256k1_scalar_clear(&non);
secp256k1_scalar_clear(&sec);
return ret;
}
int secp256k1_schnorr_verify(const secp256k1_context* ctx, const unsigned char *sig64, const unsigned char *msg32, const secp256k1_pubkey *pubkey) {
secp256k1_ge q;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(pubkey != NULL);
secp256k1_pubkey_load(ctx, &q, pubkey);
return secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64, &q, secp256k1_schnorr_msghash_sha256, msg32);
}
int secp256k1_schnorr_recover(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const unsigned char *sig64, const unsigned char *msg32) {
secp256k1_ge q;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_context_is_built(&ctx->ecmult_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(pubkey != NULL);
if (secp256k1_schnorr_sig_recover(&ctx->ecmult_ctx, sig64, &q, secp256k1_schnorr_msghash_sha256, msg32)) {
secp256k1_pubkey_save(pubkey, &q);
return 1;
} else {
memset(pubkey, 0, sizeof(*pubkey));
return 0;
}
}
int secp256k1_schnorr_generate_nonce_pair(const secp256k1_context* ctx, secp256k1_pubkey *pubnonce, unsigned char *privnonce32, const unsigned char *sec32, const unsigned char *msg32, secp256k1_nonce_function noncefp, const void* noncedata) {
int count = 0;
int ret = 1;
secp256k1_gej Qj;
secp256k1_ge Q;
secp256k1_scalar sec;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sec32 != NULL);
ARG_CHECK(pubnonce != NULL);
ARG_CHECK(privnonce32 != NULL);
if (noncefp == NULL) {
noncefp = secp256k1_nonce_function_default;
}
do {
int overflow;
ret = noncefp(privnonce32, sec32, msg32, secp256k1_schnorr_algo16, (void*)noncedata, count++);
if (!ret) {
break;
}
secp256k1_scalar_set_b32(&sec, privnonce32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&sec)) {
continue;
}
secp256k1_ecmult_gen(&ctx->ecmult_gen_ctx, &Qj, &sec);
secp256k1_ge_set_gej(&Q, &Qj);
secp256k1_pubkey_save(pubnonce, &Q);
break;
} while(1);
secp256k1_scalar_clear(&sec);
if (!ret) {
memset(pubnonce, 0, sizeof(*pubnonce));
}
return ret;
}
int secp256k1_schnorr_partial_sign(const secp256k1_context* ctx, unsigned char *sig64, const unsigned char *msg32, const unsigned char *sec32, const secp256k1_pubkey *pubnonce_others, const unsigned char *secnonce32) {
int overflow = 0;
secp256k1_scalar sec, non;
secp256k1_ge pubnon;
VERIFY_CHECK(ctx != NULL);
ARG_CHECK(secp256k1_ecmult_gen_context_is_built(&ctx->ecmult_gen_ctx));
ARG_CHECK(msg32 != NULL);
ARG_CHECK(sig64 != NULL);
ARG_CHECK(sec32 != NULL);
ARG_CHECK(secnonce32 != NULL);
ARG_CHECK(pubnonce_others != NULL);
secp256k1_scalar_set_b32(&sec, sec32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&sec)) {
return -1;
}
secp256k1_scalar_set_b32(&non, secnonce32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&non)) {
return -1;
}
secp256k1_pubkey_load(ctx, &pubnon, pubnonce_others);
return secp256k1_schnorr_sig_sign(&ctx->ecmult_gen_ctx, sig64, &sec, &non, &pubnon, secp256k1_schnorr_msghash_sha256, msg32);
}
int secp256k1_schnorr_partial_combine(const secp256k1_context* ctx, unsigned char *sig64, const unsigned char * const *sig64sin, int n) {
ARG_CHECK(sig64 != NULL);
ARG_CHECK(n >= 1);
ARG_CHECK(sig64sin != NULL);
return secp256k1_schnorr_sig_combine(sig64, n, sig64sin);
}
#endif

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/***********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php. *
***********************************************************************/
#ifndef _SECP256K1_MODULE_SCHNORR_H_
#define _SECP256K1_MODULE_SCHNORR_H_
#include "scalar.h"
#include "group.h"
typedef void (*secp256k1_schnorr_msghash)(unsigned char *h32, const unsigned char *r32, const unsigned char *msg32);
static int secp256k1_schnorr_sig_sign(const secp256k1_ecmult_gen_context* ctx, unsigned char *sig64, const secp256k1_scalar *key, const secp256k1_scalar *nonce, const secp256k1_ge *pubnonce, secp256k1_schnorr_msghash hash, const unsigned char *msg32);
static int secp256k1_schnorr_sig_verify(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, const secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32);
static int secp256k1_schnorr_sig_recover(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32);
static int secp256k1_schnorr_sig_combine(unsigned char *sig64, int n, const unsigned char * const *sig64ins);
#endif

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/***********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php. *
***********************************************************************/
#ifndef _SECP256K1_SCHNORR_IMPL_H_
#define _SECP256K1_SCHNORR_IMPL_H_
#include <string.h>
#include "schnorr.h"
#include "num.h"
#include "field.h"
#include "group.h"
#include "ecmult.h"
#include "ecmult_gen.h"
/**
* Custom Schnorr-based signature scheme. They support multiparty signing, public key
* recovery and batch validation.
*
* Rationale for verifying R's y coordinate:
* In order to support batch validation and public key recovery, the full R point must
* be known to verifiers, rather than just its x coordinate. In order to not risk
* being more strict in batch validation than normal validation, validators must be
* required to reject signatures with incorrect y coordinate. This is only possible
* by including a (relatively slow) field inverse, or a field square root. However,
* batch validation offers potentially much higher benefits than this cost.
*
* Rationale for having an implicit y coordinate oddness:
* If we commit to having the full R point known to verifiers, there are two mechanism.
* Either include its oddness in the signature, or give it an implicit fixed value.
* As the R y coordinate can be flipped by a simple negation of the nonce, we choose the
* latter, as it comes with nearly zero impact on signing or validation performance, and
* saves a byte in the signature.
*
* Signing:
* Inputs: 32-byte message m, 32-byte scalar key x (!=0), 32-byte scalar nonce k (!=0)
*
* Compute point R = k * G. Reject nonce if R's y coordinate is odd (or negate nonce).
* Compute 32-byte r, the serialization of R's x coordinate.
* Compute scalar h = Hash(r || m). Reject nonce if h == 0 or h >= order.
* Compute scalar s = k - h * x.
* The signature is (r, s).
*
*
* Verification:
* Inputs: 32-byte message m, public key point Q, signature: (32-byte r, scalar s)
*
* Signature is invalid if s >= order.
* Signature is invalid if r >= p.
* Compute scalar h = Hash(r || m). Signature is invalid if h == 0 or h >= order.
* Option 1 (faster for single verification):
* Compute point R = h * Q + s * G. Signature is invalid if R is infinity or R's y coordinate is odd.
* Signature is valid if the serialization of R's x coordinate equals r.
* Option 2 (allows batch validation and pubkey recovery):
* Decompress x coordinate r into point R, with odd y coordinate. Fail if R is not on the curve.
* Signature is valid if R + h * Q + s * G == 0.
*/
static int secp256k1_schnorr_sig_sign(const secp256k1_ecmult_gen_context* ctx, unsigned char *sig64, const secp256k1_scalar *key, const secp256k1_scalar *nonce, const secp256k1_ge *pubnonce, secp256k1_schnorr_msghash hash, const unsigned char *msg32) {
secp256k1_gej Rj;
secp256k1_ge Ra;
unsigned char h32[32];
secp256k1_scalar h, s;
int overflow;
secp256k1_scalar n;
if (secp256k1_scalar_is_zero(key) || secp256k1_scalar_is_zero(nonce)) {
return 0;
}
n = *nonce;
secp256k1_ecmult_gen(ctx, &Rj, &n);
if (pubnonce != NULL) {
secp256k1_gej_add_ge(&Rj, &Rj, pubnonce);
}
secp256k1_ge_set_gej(&Ra, &Rj);
secp256k1_fe_normalize(&Ra.y);
if (secp256k1_fe_is_odd(&Ra.y)) {
/* R's y coordinate is odd, which is not allowed (see rationale above).
Force it to be even by negating the nonce. Note that this even works
for multiparty signing, as the R point is known to all participants,
which can all decide to flip the sign in unison, resulting in the
overall R point to be negated too. */
secp256k1_scalar_negate(&n, &n);
}
secp256k1_fe_normalize(&Ra.x);
secp256k1_fe_get_b32(sig64, &Ra.x);
hash(h32, sig64, msg32);
overflow = 0;
secp256k1_scalar_set_b32(&h, h32, &overflow);
if (overflow || secp256k1_scalar_is_zero(&h)) {
secp256k1_scalar_clear(&n);
return 0;
}
secp256k1_scalar_mul(&s, &h, key);
secp256k1_scalar_negate(&s, &s);
secp256k1_scalar_add(&s, &s, &n);
secp256k1_scalar_clear(&n);
secp256k1_scalar_get_b32(sig64 + 32, &s);
return 1;
}
static int secp256k1_schnorr_sig_verify(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, const secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32) {
secp256k1_gej Qj, Rj;
secp256k1_ge Ra;
secp256k1_fe Rx;
secp256k1_scalar h, s;
unsigned char hh[32];
int overflow;
if (secp256k1_ge_is_infinity(pubkey)) {
return 0;
}
hash(hh, sig64, msg32);
overflow = 0;
secp256k1_scalar_set_b32(&h, hh, &overflow);
if (overflow || secp256k1_scalar_is_zero(&h)) {
return 0;
}
overflow = 0;
secp256k1_scalar_set_b32(&s, sig64 + 32, &overflow);
if (overflow) {
return 0;
}
if (!secp256k1_fe_set_b32(&Rx, sig64)) {
return 0;
}
secp256k1_gej_set_ge(&Qj, pubkey);
secp256k1_ecmult(ctx, &Rj, &Qj, &h, &s);
if (secp256k1_gej_is_infinity(&Rj)) {
return 0;
}
secp256k1_ge_set_gej_var(&Ra, &Rj);
secp256k1_fe_normalize_var(&Ra.y);
if (secp256k1_fe_is_odd(&Ra.y)) {
return 0;
}
return secp256k1_fe_equal_var(&Rx, &Ra.x);
}
static int secp256k1_schnorr_sig_recover(const secp256k1_ecmult_context* ctx, const unsigned char *sig64, secp256k1_ge *pubkey, secp256k1_schnorr_msghash hash, const unsigned char *msg32) {
secp256k1_gej Qj, Rj;
secp256k1_ge Ra;
secp256k1_fe Rx;
secp256k1_scalar h, s;
unsigned char hh[32];
int overflow;
hash(hh, sig64, msg32);
overflow = 0;
secp256k1_scalar_set_b32(&h, hh, &overflow);
if (overflow || secp256k1_scalar_is_zero(&h)) {
return 0;
}
overflow = 0;
secp256k1_scalar_set_b32(&s, sig64 + 32, &overflow);
if (overflow) {
return 0;
}
if (!secp256k1_fe_set_b32(&Rx, sig64)) {
return 0;
}
if (!secp256k1_ge_set_xo_var(&Ra, &Rx, 0)) {
return 0;
}
secp256k1_gej_set_ge(&Rj, &Ra);
secp256k1_scalar_inverse_var(&h, &h);
secp256k1_scalar_negate(&s, &s);
secp256k1_scalar_mul(&s, &s, &h);
secp256k1_ecmult(ctx, &Qj, &Rj, &h, &s);
if (secp256k1_gej_is_infinity(&Qj)) {
return 0;
}
secp256k1_ge_set_gej(pubkey, &Qj);
return 1;
}
static int secp256k1_schnorr_sig_combine(unsigned char *sig64, int n, const unsigned char * const *sig64ins) {
secp256k1_scalar s = SECP256K1_SCALAR_CONST(0, 0, 0, 0, 0, 0, 0, 0);
int i;
for (i = 0; i < n; i++) {
secp256k1_scalar si;
int overflow;
secp256k1_scalar_set_b32(&si, sig64ins[i] + 32, &overflow);
if (overflow) {
return -1;
}
if (i) {
if (memcmp(sig64ins[i - 1], sig64ins[i], 32) != 0) {
return -1;
}
}
secp256k1_scalar_add(&s, &s, &si);
}
if (secp256k1_scalar_is_zero(&s)) {
return 0;
}
memcpy(sig64, sig64ins[0], 32);
secp256k1_scalar_get_b32(sig64 + 32, &s);
secp256k1_scalar_clear(&s);
return 1;
}
#endif

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/**********************************************************************
* Copyright (c) 2014-2015 Pieter Wuille *
* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/
#ifndef SECP256K1_MODULE_SCHNORR_TESTS
#define SECP256K1_MODULE_SCHNORR_TESTS
#include "include/secp256k1_schnorr.h"
void test_schnorr_end_to_end(void) {
unsigned char privkey[32];
unsigned char message[32];
unsigned char schnorr_signature[64];
secp256k1_pubkey pubkey, recpubkey;
/* Generate a random key and message. */
{
secp256k1_scalar key;
random_scalar_order_test(&key);
secp256k1_scalar_get_b32(privkey, &key);
secp256k1_rand256_test(message);
}
/* Construct and verify corresponding public key. */
CHECK(secp256k1_ec_seckey_verify(ctx, privkey) == 1);
CHECK(secp256k1_ec_pubkey_create(ctx, &pubkey, privkey) == 1);
/* Schnorr sign. */
CHECK(secp256k1_schnorr_sign(ctx, schnorr_signature, message, privkey, NULL, NULL) == 1);
CHECK(secp256k1_schnorr_verify(ctx, schnorr_signature, message, &pubkey) == 1);
CHECK(secp256k1_schnorr_recover(ctx, &recpubkey, schnorr_signature, message) == 1);
CHECK(memcmp(&pubkey, &recpubkey, sizeof(pubkey)) == 0);
/* Destroy signature and verify again. */
schnorr_signature[secp256k1_rand32() % 64] += 1 + (secp256k1_rand32() % 255);
CHECK(secp256k1_schnorr_verify(ctx, schnorr_signature, message, &pubkey) == 0);
CHECK(secp256k1_schnorr_recover(ctx, &recpubkey, schnorr_signature, message) != 1 ||
memcmp(&pubkey, &recpubkey, sizeof(pubkey)) != 0);
}
/** Horribly broken hash function. Do not use for anything but tests. */
void test_schnorr_hash(unsigned char *h32, const unsigned char *r32, const unsigned char *msg32) {
int i;
for (i = 0; i < 32; i++) {
h32[i] = r32[i] ^ msg32[i];
}
}
void test_schnorr_sign_verify(void) {
unsigned char msg32[32];
unsigned char sig64[3][64];
secp256k1_gej pubkeyj[3];
secp256k1_ge pubkey[3];
secp256k1_scalar nonce[3], key[3];
int i = 0;
int k;
secp256k1_rand256_test(msg32);
for (k = 0; k < 3; k++) {
random_scalar_order_test(&key[k]);
do {
random_scalar_order_test(&nonce[k]);
if (secp256k1_schnorr_sig_sign(&ctx->ecmult_gen_ctx, sig64[k], &key[k], &nonce[k], NULL, &test_schnorr_hash, msg32)) {
break;
}
} while(1);
secp256k1_ecmult_gen(&ctx->ecmult_gen_ctx, &pubkeyj[k], &key[k]);
secp256k1_ge_set_gej_var(&pubkey[k], &pubkeyj[k]);
CHECK(secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64[k], &pubkey[k], &test_schnorr_hash, msg32));
for (i = 0; i < 4; i++) {
int pos = secp256k1_rand32() % 64;
int mod = 1 + (secp256k1_rand32() % 255);
sig64[k][pos] ^= mod;
CHECK(secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64[k], &pubkey[k], &test_schnorr_hash, msg32) == 0);
sig64[k][pos] ^= mod;
}
}
}
void test_schnorr_threshold(void) {
unsigned char msg[32];
unsigned char sec[5][32];
secp256k1_pubkey pub[5];
unsigned char nonce[5][32];
secp256k1_pubkey pubnonce[5];
unsigned char sig[5][64];
const unsigned char* sigs[5];
unsigned char allsig[64];
const secp256k1_pubkey* pubs[5];
secp256k1_pubkey allpub;
int n, i;
int damage;
int ret = 0;
damage = (secp256k1_rand32() % 2) ? (1 + (secp256k1_rand32() % 4)) : 0;
secp256k1_rand256_test(msg);
n = 2 + (secp256k1_rand32() % 4);
for (i = 0; i < n; i++) {
do {
secp256k1_rand256_test(sec[i]);
} while (!secp256k1_ec_seckey_verify(ctx, sec[i]));
CHECK(secp256k1_ec_pubkey_create(ctx, &pub[i], sec[i]));
CHECK(secp256k1_schnorr_generate_nonce_pair(ctx, &pubnonce[i], nonce[i], msg, sec[i], NULL, NULL));
pubs[i] = &pub[i];
}
if (damage == 1) {
nonce[secp256k1_rand32() % n][secp256k1_rand32() % 32] ^= 1 + (secp256k1_rand32() % 255);
} else if (damage == 2) {
sec[secp256k1_rand32() % n][secp256k1_rand32() % 32] ^= 1 + (secp256k1_rand32() % 255);
}
for (i = 0; i < n; i++) {
secp256k1_pubkey allpubnonce;
const secp256k1_pubkey *pubnonces[4];
int j;
for (j = 0; j < i; j++) {
pubnonces[j] = &pubnonce[j];
}
for (j = i + 1; j < n; j++) {
pubnonces[j - 1] = &pubnonce[j];
}
CHECK(secp256k1_ec_pubkey_combine(ctx, &allpubnonce, pubnonces, n - 1));
ret |= (secp256k1_schnorr_partial_sign(ctx, sig[i], msg, sec[i], &allpubnonce, nonce[i]) != 1) * 1;
sigs[i] = sig[i];
}
if (damage == 3) {
sig[secp256k1_rand32() % n][secp256k1_rand32() % 64] ^= 1 + (secp256k1_rand32() % 255);
}
ret |= (secp256k1_ec_pubkey_combine(ctx, &allpub, pubs, n) != 1) * 2;
if ((ret & 1) == 0) {
ret |= (secp256k1_schnorr_partial_combine(ctx, allsig, sigs, n) != 1) * 4;
}
if (damage == 4) {
allsig[secp256k1_rand32() % 32] ^= 1 + (secp256k1_rand32() % 255);
}
if ((ret & 7) == 0) {
ret |= (secp256k1_schnorr_verify(ctx, allsig, msg, &allpub) != 1) * 8;
}
CHECK((ret == 0) == (damage == 0));
}
void test_schnorr_recovery(void) {
unsigned char msg32[32];
unsigned char sig64[64];
secp256k1_ge Q;
secp256k1_rand256_test(msg32);
secp256k1_rand256_test(sig64);
secp256k1_rand256_test(sig64 + 32);
if (secp256k1_schnorr_sig_recover(&ctx->ecmult_ctx, sig64, &Q, &test_schnorr_hash, msg32) == 1) {
CHECK(secp256k1_schnorr_sig_verify(&ctx->ecmult_ctx, sig64, &Q, &test_schnorr_hash, msg32) == 1);
}
}
void run_schnorr_tests(void) {
int i;
for (i = 0; i < 32*count; i++) {
test_schnorr_end_to_end();
}
for (i = 0; i < 32 * count; i++) {
test_schnorr_sign_verify();
}
for (i = 0; i < 16 * count; i++) {
test_schnorr_recovery();
}
for (i = 0; i < 10 * count; i++) {
test_schnorr_threshold();
}
}
#endif