int cp_pss_ver(g1_t a, g1_t b, uint8_t *msg, int len, g2_t g, g2_t x, g2_t y) {
g1_t p[2];
g2_t r[2];
gt_t e;
bn_t m, n;
int result = 1;
g1_null(p[0]);
g1_null(p[1]);
g2_null(r[0]);
g2_null(r[1]);
gt_null(e);
bn_null(m);
bn_null(n);
TRY {
g1_new(p[0]);
g1_new(p[1]);
g2_new(r[0]);
g2_new(r[1]);
gt_new(e);
bn_new(m);
bn_new(n);
if (g1_is_infty(a)) {
result = 0;
}
g1_copy(p[0], a);
g1_copy(p[1], b);
g2_copy(r[1], g);
g2_neg(r[1], r[1]);
g1_get_ord(n);
bn_read_bin(m, msg, len);
bn_mod(m, m, n);
g2_mul(r[0], y, m);
g2_add(r[0], r[0], x);
g2_norm(r[0], r[0]);
pc_map_sim(e, p, r, 2);
if (!gt_is_unity(e)) {
result = 0;
}
}
CATCH_ANY {
THROW(ERR_CAUGHT);
}
FINALLY {
g1_free(p[0]);
g1_free(p[1]);
g2_free(r[0]);
g2_free(r[1]);
gt_free(e);
bn_free(m);
bn_free(n);
}
return result;
}
int cp_bgn_dec1(dig_t *out, g1_t in[2], bgn_t prv) {
bn_t r, n;
g1_t s, t, u;
int i, result = STS_ERR;
bn_null(n);
bn_null(r);
g1_null(s);
g1_null(t);
g1_null(u);
TRY {
bn_new(n);
bn_new(r);
g1_new(s);
g1_new(t);
g1_new(u);
g1_get_ord(n);
/* Compute T = x(ym + r)G - (zm + xr)G = m(xy - z)G. */
g1_mul(t, in[0], prv->x);
g1_sub(t, t, in[1]);
g1_norm(t, t);
/* Compute U = (xy - z)G and find m. */
bn_mul(r, prv->x, prv->y);
bn_sub(r, r, prv->z);
bn_mod(r, r, n);
g1_mul_gen(s, r);
g1_copy(u, s);
if (g1_is_infty(t) == 1){
*out = 0;
result = STS_OK;
} else {
for (i = 0; i < INT_MAX; i++) {
if (g1_cmp(t, u) == CMP_EQ) {
*out = i + 1;
result = STS_OK;
break;
}
g1_add(u, u, s);
g1_norm(u, u);
}
}
} CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(n);
bn_free(r);
g1_free(s);
g1_free(t);
g1_free(u);
}
return result;
}
int cp_bls_sig(g1_t s, uint8_t *msg, int len, bn_t d) {
g1_t p;
int result = STS_OK;
g1_null(p);
TRY {
g1_new(p);
g1_map(p, msg, len);
g1_mul(s, p, d);
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
g1_free(p);
}
return result;
}
int cp_bgn_enc1(g1_t out[2], dig_t in, bgn_t pub) {
bn_t r, n;
g1_t t;
int result = STS_OK;
bn_null(n);
bn_null(r);
g1_null(t);
TRY {
bn_new(n);
bn_new(r);
g1_new(t);
g1_get_ord(n);
bn_rand_mod(r, n);
/* Compute c0 = (ym + r)G. */
g1_mul_dig(out[0], pub->gy, in);
g1_mul_gen(t, r);
g1_add(out[0], out[0], t);
g1_norm(out[0], out[0]);
/* Compute c1 = (zm + xr)G. */
g1_mul_dig(out[1], pub->gz, in);
g1_mul(t, pub->gx, r);
g1_add(out[1], out[1], t);
g1_norm(out[1], out[1]);
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(n);
bn_free(r);
g1_free(t);
}
return result;
}
void gt_get_gen(gt_t a) {
g1_t g1;
g2_t g2;
g1_null(g1);
g2_null(g2);
TRY {
g1_new(g1);
g2_new(g2);
g1_get_gen(g1);
g2_get_gen(g2);
pc_map(a, g1, g2);
} CATCH_ANY {
THROW(ERR_CAUGHT);
} FINALLY {
g1_free(g1);
g2_free(g2);
}
}
int cp_bls_ver(g1_t s, uint8_t *msg, int len, g2_t q) {
g1_t p;
g2_t g;
gt_t e1, e2;
int result = 0;
g1_null(p);
g2_null(g);
gt_null(e1);
gt_null(e2);
TRY {
g1_new(p);
g2_new(g);
gt_new(e1);
gt_new(e2);
g2_get_gen(g);
g1_map(p, msg, len);
pc_map(e1, p, q);
pc_map(e2, s, g);
if (gt_cmp(e1, e2) == CMP_EQ) {
result = 1;
}
}
CATCH_ANY {
THROW(ERR_CAUGHT);
}
FINALLY {
g1_free(p);
g2_free(g);
gt_free(e1);
gt_free(e2);
}
return result;
}
int cp_bbs_gen(bn_t d, g2_t q, gt_t z) {
bn_t n;
g1_t g;
int result = STS_OK;
bn_null(n);
g1_null(g);
TRY {
bn_new(n);
g1_new(g);
g1_get_gen(g);
g2_get_gen(q);
/* z = e(g1, g2). */
pc_map(z, g, q);
g2_get_ord(n);
do {
bn_rand(d, BN_POS, 2 * pc_param_level());
bn_mod(d, d, n);
} while (bn_is_zero(d));
/* q = d * g2. */
g2_mul_gen(q, d);
g2_norm(q, q);
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(n);
g1_free(g);
}
return result;
}
int cp_psb_ver(g1_t a, g1_t b, uint8_t *msgs[], int lens[], g2_t g, g2_t x,
g2_t y[], int l) {
g1_t p[2];
g2_t q[2];
gt_t e;
bn_t m, n;
int i, result = 1;
g1_null(p[0]);
g1_null(p[1]);
g2_null(q[0]);
g2_null(q[1]);
gt_null(e);
bn_null(m);
bn_null(n);
TRY {
g1_new(p[0]);
g1_new(p[1]);
g2_new(q[0]);
g2_new(q[1]);
gt_new(e);
bn_new(m);
bn_new(n);
if (g1_is_infty(a)) {
result = 0;
}
/* Check that e(a, x \prod y_i^m_i) = e(b, g). */
g1_copy(p[0], a);
g1_copy(p[1], b);
g2_copy(q[0], x);
g1_get_ord(n);
for (i = 0; i < l; i++) {
bn_read_bin(m, msgs[i], lens[i]);
bn_mod(m, m, n);
g2_mul(q[1], y[i], m);
g2_add(q[0], q[0], q[1]);
}
g2_norm(q[0], q[0]);
g2_copy(q[1], g);
g2_neg(q[1], q[1]);
pc_map_sim(e, p, q, 2);
if (!gt_is_unity(e)) {
result = 0;
}
}
CATCH_ANY {
THROW(ERR_CAUGHT);
}
FINALLY {
g1_free(p[0]);
g1_free(p[1]);
g2_free(q[0]);
g2_free(q[1]);
gt_free(e);
bn_free(m);
bn_free(n);
}
return result;
}
int cp_sokaka_key(uint8_t *key, unsigned int key_len, char *id1,
int len1, sokaka_t k, char *id2, int len2) {
int first = 0, result = STS_OK;
g1_t p;
g2_t q;
gt_t e;
g1_null(p);
g2_null(q);
gt_null(e);
TRY {
g1_new(p);
g2_new(q);
gt_new(e);
if (len1 == len2) {
if (strncmp(id1, id2, len1) == 0) {
THROW(ERR_NO_VALID);
}
first = (strncmp(id1, id2, len1) < 0 ? 1 : 2);
} else {
if (len1 < len2) {
if (strncmp(id1, id2, len1) == 0) {
first = 1;
} else {
first = (strncmp(id1, id2, len2) < 0 ? 1 : 2);
}
} else {
if (strncmp(id1, id2, len2) == 0) {
first = 2;
} else {
first = (strncmp(id1, id2, len2) < 0 ? 1 : 2);
}
}
}
if (pc_map_is_type1()) {
g2_map(q, (uint8_t *)id2, len2);
pc_map(e, k->s1, q);
} else {
if (first == 1) {
g2_map(q, (uint8_t *)id2, len2);
pc_map(e, k->s1, q);
} else {
g1_map(p, (uint8_t *)id2, len2);
pc_map(e, p, k->s2);
}
}
/* Allocate size for storing the output. */
uint8_t buf[gt_size_bin(e, 0)];
gt_write_bin(buf, sizeof(buf), e, 0);
md_kdf1(key, key_len, buf, sizeof(buf));
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
g1_free(p);
g2_free(q);
gt_free(e);
}
return result;
}
int cp_bgn_dec(dig_t *out, gt_t in[4], bgn_t prv) {
int i, result = STS_ERR;
g1_t g;
g2_t h;
gt_t t[4];
bn_t n, r, s;
bn_null(n);
bn_null(r);
bn_null(s);
g1_null(g);
g2_null(h);
TRY {
bn_new(n);
bn_new(r);
bn_new(s);
g1_new(g);
g2_new(h);
for (i = 0; i < 4; i++) {
gt_null(t[i]);
gt_new(t[i]);
}
gt_exp(t[0], in[0], prv->x);
gt_exp(t[0], t[0], prv->x);
gt_mul(t[1], in[1], in[2]);
gt_exp(t[1], t[1], prv->x);
gt_inv(t[1], t[1]);
gt_mul(t[3], in[3], t[1]);
gt_mul(t[3], t[3], t[0]);
gt_get_ord(n);
g1_get_gen(g);
g2_get_gen(h);
bn_mul(r, prv->x, prv->y);
bn_sqr(r, r);
bn_mul(s, prv->x, prv->y);
bn_mul(s, s, prv->z);
bn_sub(r, r, s);
bn_sub(r, r, s);
bn_sqr(s, prv->z);
bn_add(r, r, s);
bn_mod(r, r, n);
pc_map(t[1], g, h);
gt_exp(t[1], t[1], r);
gt_copy(t[2], t[1]);
if (gt_is_unity(t[3]) == 1) {
*out = 0;
result = STS_OK;
} else {
for (i = 0; i < INT_MAX; i++) {
if (gt_cmp(t[2], t[3]) == CMP_EQ) {
*out = i + 1;
result = STS_OK;
break;
}
gt_mul(t[2], t[2], t[1]);
}
}
} CATCH_ANY {
result = STS_ERR;
} FINALLY {
bn_free(n);
bn_free(r);
bn_free(s);
g1_free(g);
g2_free(h);
for (i = 0; i < 4; i++) {
gt_free(t[i]);
}
}
return result;
}