void test_sqrt(const secp256k1_fe_t *a, const secp256k1_fe_t *k) {
secp256k1_fe_t r1, r2;
int v = secp256k1_fe_sqrt(&r1, a);
CHECK((v == 0) == (k == NULL));
if (k != NULL) {
/* Check that the returned root is +/- the given known answer */
secp256k1_fe_negate(&r2, &r1, 1);
secp256k1_fe_add(&r1, k); secp256k1_fe_add(&r2, k);
secp256k1_fe_normalize(&r1); secp256k1_fe_normalize(&r2);
CHECK(secp256k1_fe_is_zero(&r1) || secp256k1_fe_is_zero(&r2));
}
}
void bench_field_normalize(void* arg) {
int i;
bench_inv_t *data = (bench_inv_t*)arg;
for (i = 0; i < 2000000; i++) {
secp256k1_fe_normalize(&data->fe_x);
}
}
void random_field_element_magnitude(secp256k1_fe_t *fe) {
secp256k1_fe_normalize(fe);
int n = secp256k1_rand32() % 4;
for (int i = 0; i < n; i++) {
secp256k1_fe_negate(fe, fe, 1 + 2*i);
secp256k1_fe_negate(fe, fe, 2 + 2*i);
}
}
void r_from_k(secp256k1_scalar *r, const secp256k1_ge *group, int k) {
secp256k1_fe x;
unsigned char x_bin[32];
k %= EXHAUSTIVE_TEST_ORDER;
x = group[k].x;
secp256k1_fe_normalize(&x);
secp256k1_fe_get_b32(x_bin, &x);
secp256k1_scalar_set_b32(r, x_bin, NULL);
}
void random_fe_non_zero(secp256k1_fe_t *nz) {
int tries = 10;
while (--tries >= 0) {
random_fe(nz);
secp256k1_fe_normalize(nz);
if (!secp256k1_fe_is_zero(nz))
break;
}
/* Infinitesimal probability of spurious failure here */
CHECK(tries >= 0);
}
void run_sqr(void) {
secp256k1_fe_t x, s;
{
secp256k1_fe_set_int(&x, 1);
secp256k1_fe_negate(&x, &x, 1);
for (int i=1; i<=512; ++i) {
secp256k1_fe_mul_int(&x, 2);
secp256k1_fe_normalize(&x);
secp256k1_fe_sqr(&s, &x);
}
}
}
void test_ge(void) {
char ca[135];
char cb[68];
int rlen;
secp256k1_ge_t a, b, i, n;
random_group_element_test(&a);
random_group_element_test(&b);
rlen = sizeof(ca);
secp256k1_ge_get_hex(ca,&rlen,&a);
CHECK(rlen > 4 && rlen <= (int)sizeof(ca));
rlen = sizeof(cb);
secp256k1_ge_get_hex(cb,&rlen,&b); /* Intentionally undersized buffer. */
n = a;
secp256k1_fe_normalize(&a.y);
secp256k1_fe_negate(&n.y, &a.y, 1);
secp256k1_ge_set_infinity(&i);
random_field_element_magnitude(&a.x);
random_field_element_magnitude(&a.y);
random_field_element_magnitude(&b.x);
random_field_element_magnitude(&b.y);
random_field_element_magnitude(&n.x);
random_field_element_magnitude(&n.y);
secp256k1_gej_t aj, bj, ij, nj;
random_group_element_jacobian_test(&aj, &a);
random_group_element_jacobian_test(&bj, &b);
secp256k1_gej_set_infinity(&ij);
random_group_element_jacobian_test(&nj, &n);
random_field_element_magnitude(&aj.x);
random_field_element_magnitude(&aj.y);
random_field_element_magnitude(&aj.z);
random_field_element_magnitude(&bj.x);
random_field_element_magnitude(&bj.y);
random_field_element_magnitude(&bj.z);
random_field_element_magnitude(&nj.x);
random_field_element_magnitude(&nj.y);
random_field_element_magnitude(&nj.z);
/* gej + gej adds */
secp256k1_gej_t aaj; secp256k1_gej_add_var(&aaj, &aj, &aj);
secp256k1_gej_t abj; secp256k1_gej_add_var(&abj, &aj, &bj);
secp256k1_gej_t aij; secp256k1_gej_add_var(&aij, &aj, &ij);
secp256k1_gej_t anj; secp256k1_gej_add_var(&anj, &aj, &nj);
secp256k1_gej_t iaj; secp256k1_gej_add_var(&iaj, &ij, &aj);
secp256k1_gej_t iij; secp256k1_gej_add_var(&iij, &ij, &ij);
/* gej + ge adds */
secp256k1_gej_t aa; secp256k1_gej_add_ge_var(&aa, &aj, &a);
secp256k1_gej_t ab; secp256k1_gej_add_ge_var(&ab, &aj, &b);
secp256k1_gej_t ai; secp256k1_gej_add_ge_var(&ai, &aj, &i);
secp256k1_gej_t an; secp256k1_gej_add_ge_var(&an, &aj, &n);
secp256k1_gej_t ia; secp256k1_gej_add_ge_var(&ia, &ij, &a);
secp256k1_gej_t ii; secp256k1_gej_add_ge_var(&ii, &ij, &i);
/* const gej + ge adds */
secp256k1_gej_t aac; secp256k1_gej_add_ge(&aac, &aj, &a);
secp256k1_gej_t abc; secp256k1_gej_add_ge(&abc, &aj, &b);
secp256k1_gej_t anc; secp256k1_gej_add_ge(&anc, &aj, &n);
secp256k1_gej_t iac; secp256k1_gej_add_ge(&iac, &ij, &a);
CHECK(secp256k1_gej_is_infinity(&an));
CHECK(secp256k1_gej_is_infinity(&anj));
CHECK(secp256k1_gej_is_infinity(&anc));
gej_equals_gej(&aa, &aaj);
gej_equals_gej(&aa, &aac);
gej_equals_gej(&ab, &abj);
gej_equals_gej(&ab, &abc);
gej_equals_gej(&an, &anj);
gej_equals_gej(&an, &anc);
gej_equals_gej(&ia, &iaj);
gej_equals_gej(&ai, &aij);
gej_equals_gej(&ii, &iij);
ge_equals_gej(&a, &ai);
ge_equals_gej(&a, &ai);
ge_equals_gej(&a, &iaj);
ge_equals_gej(&a, &iaj);
ge_equals_gej(&a, &iac);
}
int check_fe_equal(const secp256k1_fe_t *a, const secp256k1_fe_t *b) {
secp256k1_fe_t an = *a; secp256k1_fe_normalize(&an);
secp256k1_fe_t bn = *b; secp256k1_fe_normalize(&bn);
return secp256k1_fe_equal(&an, &bn);
}
void test_ge(void) {
secp256k1_ge_t a, b, i, n;
random_group_element_test(&a);
random_group_element_test(&b);
n = a;
secp256k1_fe_normalize(&a.y);
secp256k1_fe_negate(&n.y, &a.y, 1);
secp256k1_ge_set_infinity(&i);
random_field_element_magnitude(&a.x);
random_field_element_magnitude(&a.y);
random_field_element_magnitude(&b.x);
random_field_element_magnitude(&b.y);
random_field_element_magnitude(&n.x);
random_field_element_magnitude(&n.y);
secp256k1_gej_t aj, bj, ij, nj;
random_group_element_jacobian_test(&aj, &a);
random_group_element_jacobian_test(&bj, &b);
secp256k1_gej_set_infinity(&ij);
random_group_element_jacobian_test(&nj, &n);
random_field_element_magnitude(&aj.x);
random_field_element_magnitude(&aj.y);
random_field_element_magnitude(&aj.z);
random_field_element_magnitude(&bj.x);
random_field_element_magnitude(&bj.y);
random_field_element_magnitude(&bj.z);
random_field_element_magnitude(&nj.x);
random_field_element_magnitude(&nj.y);
random_field_element_magnitude(&nj.z);
/* gej + gej adds */
secp256k1_gej_t aaj; secp256k1_gej_add_var(&aaj, &aj, &aj);
secp256k1_gej_t abj; secp256k1_gej_add_var(&abj, &aj, &bj);
secp256k1_gej_t aij; secp256k1_gej_add_var(&aij, &aj, &ij);
secp256k1_gej_t anj; secp256k1_gej_add_var(&anj, &aj, &nj);
secp256k1_gej_t iaj; secp256k1_gej_add_var(&iaj, &ij, &aj);
secp256k1_gej_t iij; secp256k1_gej_add_var(&iij, &ij, &ij);
/* gej + ge adds */
secp256k1_gej_t aa; secp256k1_gej_add_ge_var(&aa, &aj, &a);
secp256k1_gej_t ab; secp256k1_gej_add_ge_var(&ab, &aj, &b);
secp256k1_gej_t ai; secp256k1_gej_add_ge_var(&ai, &aj, &i);
secp256k1_gej_t an; secp256k1_gej_add_ge_var(&an, &aj, &n);
secp256k1_gej_t ia; secp256k1_gej_add_ge_var(&ia, &ij, &a);
secp256k1_gej_t ii; secp256k1_gej_add_ge_var(&ii, &ij, &i);
/* const gej + ge adds */
secp256k1_gej_t aac; secp256k1_gej_add_ge(&aac, &aj, &a);
secp256k1_gej_t abc; secp256k1_gej_add_ge(&abc, &aj, &b);
secp256k1_gej_t anc; secp256k1_gej_add_ge(&anc, &aj, &n);
secp256k1_gej_t iac; secp256k1_gej_add_ge(&iac, &ij, &a);
CHECK(secp256k1_gej_is_infinity(&an));
CHECK(secp256k1_gej_is_infinity(&anj));
CHECK(secp256k1_gej_is_infinity(&anc));
gej_equals_gej(&aa, &aaj);
gej_equals_gej(&aa, &aac);
gej_equals_gej(&ab, &abj);
gej_equals_gej(&ab, &abc);
gej_equals_gej(&an, &anj);
gej_equals_gej(&an, &anc);
gej_equals_gej(&ia, &iaj);
gej_equals_gej(&ai, &aij);
gej_equals_gej(&ii, &iij);
ge_equals_gej(&a, &ai);
ge_equals_gej(&a, &ai);
ge_equals_gej(&a, &iaj);
ge_equals_gej(&a, &iaj);
ge_equals_gej(&a, &iac);
}
void test_exhaustive_recovery_sign(const secp256k1_context *ctx, const secp256k1_ge *group, int order) {
int i, j, k;
/* Loop */
for (i = 1; i < order; i++) { /* message */
for (j = 1; j < order; j++) { /* key */
for (k = 1; k < order; k++) { /* nonce */
const int starting_k = k;
secp256k1_fe r_dot_y_normalized;
secp256k1_ecdsa_recoverable_signature rsig;
secp256k1_ecdsa_signature sig;
secp256k1_scalar sk, msg, r, s, expected_r;
unsigned char sk32[32], msg32[32];
int expected_recid;
int recid;
secp256k1_scalar_set_int(&msg, i);
secp256k1_scalar_set_int(&sk, j);
secp256k1_scalar_get_b32(sk32, &sk);
secp256k1_scalar_get_b32(msg32, &msg);
secp256k1_ecdsa_sign_recoverable(ctx, &rsig, msg32, sk32, secp256k1_nonce_function_smallint, &k);
/* Check directly */
secp256k1_ecdsa_recoverable_signature_load(ctx, &r, &s, &recid, &rsig);
r_from_k(&expected_r, group, k);
CHECK(r == expected_r);
CHECK((k * s) % order == (i + r * j) % order ||
(k * (EXHAUSTIVE_TEST_ORDER - s)) % order == (i + r * j) % order);
/* In computing the recid, there is an overflow condition that is disabled in
* scalar_low_impl.h `secp256k1_scalar_set_b32` because almost every r.y value
* will exceed the group order, and our signing code always holds out for r
* values that don't overflow, so with a proper overflow check the tests would
* loop indefinitely. */
r_dot_y_normalized = group[k].y;
secp256k1_fe_normalize(&r_dot_y_normalized);
/* Also the recovery id is flipped depending if we hit the low-s branch */
if ((k * s) % order == (i + r * j) % order) {
expected_recid = secp256k1_fe_is_odd(&r_dot_y_normalized) ? 1 : 0;
} else {
expected_recid = secp256k1_fe_is_odd(&r_dot_y_normalized) ? 0 : 1;
}
CHECK(recid == expected_recid);
/* Convert to a standard sig then check */
secp256k1_ecdsa_recoverable_signature_convert(ctx, &sig, &rsig);
secp256k1_ecdsa_signature_load(ctx, &r, &s, &sig);
/* Note that we compute expected_r *after* signing -- this is important
* because our nonce-computing function function might change k during
* signing. */
r_from_k(&expected_r, group, k);
CHECK(r == expected_r);
CHECK((k * s) % order == (i + r * j) % order ||
(k * (EXHAUSTIVE_TEST_ORDER - s)) % order == (i + r * j) % order);
/* Overflow means we've tried every possible nonce */
if (k < starting_k) {
break;
}
}
}
}
}
