int cp_phpe_enc(uint8_t *out, int *out_len, uint8_t *in, int in_len, bn_t n) {
bn_t g, m, r, s;
int size, result = STS_OK;
bn_null(g);
bn_null(m);
bn_null(r);
bn_null(s);
size = bn_size_bin(n);
if (n == NULL || in_len <= 0 || in_len > size) {
return STS_ERR;
}
TRY {
bn_new(g);
bn_new(m);
bn_new(r);
bn_new(s);
/* Represent m as a padded element of Z_n. */
bn_read_bin(m, in, in_len);
/* Generate r in Z_n^*. */
bn_rand_mod(r, n);
/* Compute c = (g^m)(r^n) mod n^2. */
bn_add_dig(g, n, 1);
bn_sqr(s, n);
bn_mxp(m, g, m, s);
bn_mxp(r, r, n, s);
bn_mul(m, m, r);
bn_mod(m, m, s);
if (2 * size <= *out_len) {
*out_len = 2 * size;
memset(out, 0, *out_len);
bn_write_bin(out, *out_len, m);
} else {
result = STS_ERR;
}
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(g);
bn_free(m);
bn_free(r);
bn_free(s);
}
return result;
}
int cp_bdpe_dec(dig_t *out, uint8_t *in, int in_len, bdpe_t prv) {
bn_t m, t, z;
unsigned i;
int size, result = STS_OK;
size = bn_size_bin(prv->n);
if (in_len < 0 || in_len != size) {
return STS_ERR;
}
bn_null(m);
bn_null(t);
bn_null(z);
TRY {
bn_new(m);
bn_new(t);
bn_new(z);
/* Compute t = (p-1)(q-1)/block. */
bn_mul(t, prv->p, prv->q);
bn_sub(t, t, prv->p);
bn_sub(t, t, prv->q);
bn_add_dig(t, t, 1);
bn_div_dig(t, t, prv->t);
bn_read_bin(m, in, in_len);
bn_mxp(m, m, t, prv->n);
bn_mxp(t, prv->y, t, prv->n);
for (i = 0; i < prv->t; i++) {
bn_mxp_dig(z, t, i, prv->n);
if (bn_cmp(z, m) == CMP_EQ) {
*out = i;
break;
}
}
if (i == prv->t) {
result = STS_ERR;
}
} CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(m);
bn_free(t);
bn_free(z);
}
return result;
}
status_t element_pow_int(element_t c, element_t a, integer_t b)
{
GroupType type = a->type;
// TODO: c (type) = a (type) ^ b (ZR)
LEAVE_IF( c->isInitialized != TRUE || a->isInitialized != TRUE, "uninitialized argument.");
EXIT_IF_NOT_SAME(c, a);
LEAVE_IF(b == NULL, "uninitialized integer.");
status_t result = ELEMENT_OK;
LEAVE_IF( c->type != type, "result initialized but invalid type.");
switch(type) {
case ZR: bn_mxp(c->bn, a->bn, b, a->order);
break;
case G1: g1_mul(c->g1, a->g1, b);
break;
case G2: g2_mul(c->g2, a->g2, b);
break;
case GT: gt_exp(c->gt, a->gt, b);
break;
default:
result = ELEMENT_INVALID_TYPES;
break;
}
return result;
}
status_t element_pow_zr(element_t c, element_t a, element_t b)
{
GroupType type = a->type;
// c (type) = a (type) ^ b (ZR)
LEAVE_IF( c->isInitialized != TRUE || a->isInitialized != TRUE, "uninitialized argument.");
EXIT_IF_NOT_SAME(c, a);
LEAVE_IF(a->isInitialized != TRUE, "invalid argument.");
LEAVE_IF(b->isInitialized != TRUE || b->type != ZR, "invalid type.");
if(type == ZR) {
bn_mxp(c->bn, a->bn, b->bn, a->order);
}
else if(type == G1) {
g1_mul(c->g1, a->g1, b->bn);
}
else if(type == G2) {
g2_mul(c->g2, a->g2, b->bn);
}
else if(type == GT) {
gt_exp(c->gt, a->gt, b->bn);
}
else {
return ELEMENT_INVALID_TYPES;
}
return ELEMENT_OK;
}
int cp_phpe_dec(uint8_t *out, int out_len, uint8_t *in, int in_len, bn_t n,
bn_t l) {
bn_t c, u, s;
int size, result = STS_OK;
size = bn_size_bin(n);
if (in_len < 0 || in_len != 2 * size) {
return STS_ERR;
}
bn_null(c);
bn_null(u);
bn_null(s);
TRY {
bn_new(c);
bn_new(u);
bn_new(s);
/* Compute (c^l mod n^2) * u mod n. */
bn_sqr(s, n);
bn_read_bin(c, in, in_len);
bn_mxp(c, c, l, s);
bn_sub_dig(c, c, 1);
bn_div(c, c, n);
bn_gcd_ext(s, u, NULL, l, n);
if (bn_sign(u) == BN_NEG) {
bn_add(u, u, n);
}
bn_mul(c, c, u);
bn_mod(c, c, n);
size = bn_size_bin(c);
if (size <= out_len) {
memset(out, 0, out_len);
bn_write_bin(out + (out_len - size), size, c);
} else {
result = STS_ERR;
}
} CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(c);
bn_free(u);
bn_free(s);
}
return result;
}
int cp_bdpe_enc(uint8_t *out, int *out_len, dig_t in, bdpe_t pub) {
bn_t m, u;
int size, result = STS_OK;
bn_null(m);
bn_null(u);
size = bn_size_bin(pub->n);
if (in > pub->t) {
return STS_ERR;
}
TRY {
bn_new(m);
bn_new(u);
bn_set_dig(m, in);
do {
bn_rand(u, BN_POS, bn_bits(pub->n));
bn_mod(u, u, pub->n);
} while (bn_is_zero(u));
bn_mxp(m, pub->y, m, pub->n);
bn_mxp_dig(u, u, pub->t, pub->n);
bn_mul(m, m, u);
bn_mod(m, m, pub->n);
if (size <= *out_len) {
*out_len = size;
memset(out, 0, *out_len);
bn_write_bin(out, size, m);
} else {
result = STS_ERR;
}
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(m);
bn_free(u);
}
return result;
}
int bn_factor(bn_t c, const bn_t a) {
bn_t t0, t1;
int result;
unsigned int i, tests;
bn_null(t0);
bn_null(t1);
result = 1;
if (bn_is_even(a)) {
bn_set_dig(c, 2);
return 1;
}
TRY {
bn_new(t0);
bn_new(t1);
bn_set_dig(t0, 2);
#if WORD == 8
tests = 255;
#else
tests = 65535;
#endif
for (i = 2; i < tests; i++) {
bn_set_dig(t1, i);
bn_mxp(t0, t0, t1, a);
}
bn_sub_dig(t0, t0, 1);
bn_gcd(t1, t0, a);
if (bn_cmp_dig(t1, 1) == CMP_GT && bn_cmp(t1, a) == CMP_LT) {
bn_copy(c, t1);
} else {
result = 0;
}
} CATCH_ANY {
THROW(ERR_CAUGHT);
} FINALLY {
bn_free(t0);
bn_free(t1);
}
return result;
}
int cp_rsa_enc(uint8_t *out, int *out_len, uint8_t *in, int in_len, rsa_t pub) {
bn_t m, eb;
int size, pad_len, result = STS_OK;
bn_null(m);
bn_null(eb);
size = bn_size_bin(pub->n);
if (pub == NULL || in_len <= 0 || in_len > (size - RSA_PAD_LEN)) {
return STS_ERR;
}
TRY {
bn_new(m);
bn_new(eb);
bn_zero(m);
bn_zero(eb);
#if CP_RSAPD == BASIC
if (pad_basic(eb, &pad_len, in_len, size, RSA_ENC) == STS_OK) {
#elif CP_RSAPD == PKCS1
if (pad_pkcs1(eb, &pad_len, in_len, size, RSA_ENC) == STS_OK) {
#elif CP_RSAPD == PKCS2
if (pad_pkcs2(eb, &pad_len, in_len, size, RSA_ENC) == STS_OK) {
#endif
bn_read_bin(m, in, in_len);
bn_add(eb, eb, m);
#if CP_RSAPD == PKCS2
pad_pkcs2(eb, &pad_len, in_len, size, RSA_ENC_FIN);
#endif
bn_mxp(eb, eb, pub->e, pub->n);
if (size <= *out_len) {
*out_len = size;
memset(out, 0, *out_len);
bn_write_bin(out, size, eb);
} else {
result = STS_ERR;
}
} else {
result = STS_ERR;
}
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(m);
bn_free(eb);
}
return result;
}
#if CP_RSA == BASIC || !defined(STRIP)
int cp_rsa_dec_basic(uint8_t *out, int *out_len, uint8_t *in, int in_len, rsa_t prv) {
bn_t m, eb;
int size, pad_len, result = STS_OK;
size = bn_size_bin(prv->n);
if (prv == NULL || in_len != size || in_len < RSA_PAD_LEN) {
return STS_ERR;
}
bn_null(m);
bn_null(eb);
TRY {
bn_new(m);
bn_new(eb);
bn_read_bin(eb, in, in_len);
bn_mxp(eb, eb, prv->d, prv->n);
if (bn_cmp(eb, prv->n) != CMP_LT) {
result = STS_ERR;
}
#if CP_RSAPD == BASIC
if (pad_basic(eb, &pad_len, in_len, size, RSA_DEC) == STS_OK) {
#elif CP_RSAPD == PKCS1
if (pad_pkcs1(eb, &pad_len, in_len, size, RSA_DEC) == STS_OK) {
#elif CP_RSAPD == PKCS2
if (pad_pkcs2(eb, &pad_len, in_len, size, RSA_DEC) == STS_OK) {
#endif
size = size - pad_len;
if (size <= *out_len) {
memset(out, 0, size);
bn_write_bin(out, size, eb);
*out_len = size;
} else {
result = STS_ERR;
}
} else {
result = STS_ERR;
}
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(m);
bn_free(eb);
}
return result;
}
#endif
#if CP_RSA == QUICK || !defined(STRIP)
int cp_rsa_dec_quick(uint8_t *out, int *out_len, uint8_t *in, int in_len, rsa_t prv) {
bn_t m, eb;
int size, pad_len, result = STS_OK;
bn_null(m);
bn_null(eb);
size = bn_size_bin(prv->n);
if (prv == NULL || in_len != size || in_len < RSA_PAD_LEN) {
return STS_ERR;
}
TRY {
bn_new(m);
bn_new(eb);
bn_read_bin(eb, in, in_len);
bn_copy(m, eb);
/* m1 = c^dP mod p. */
bn_mxp(eb, eb, prv->dp, prv->p);
/* m2 = c^dQ mod q. */
bn_mxp(m, m, prv->dq, prv->q);
/* m1 = m1 - m2 mod p. */
bn_sub(eb, eb, m);
while (bn_sign(eb) == BN_NEG) {
bn_add(eb, eb, prv->p);
}
bn_mod(eb, eb, prv->p);
/* m1 = qInv(m1 - m2) mod p. */
bn_mul(eb, eb, prv->qi);
bn_mod(eb, eb, prv->p);
/* m = m2 + m1 * q. */
bn_mul(eb, eb, prv->q);
bn_add(eb, eb, m);
if (bn_cmp(eb, prv->n) != CMP_LT) {
result = STS_ERR;
}
#if CP_RSAPD == BASIC
if (pad_basic(eb, &pad_len, in_len, size, RSA_DEC) == STS_OK) {
#elif CP_RSAPD == PKCS1
if (pad_pkcs1(eb, &pad_len, in_len, size, RSA_DEC) == STS_OK) {
#elif CP_RSAPD == PKCS2
if (pad_pkcs2(eb, &pad_len, in_len, size, RSA_DEC) == STS_OK) {
#endif
size = size - pad_len;
if (size <= *out_len) {
memset(out, 0, size);
bn_write_bin(out, size, eb);
*out_len = size;
} else {
result = STS_ERR;
}
} else {
result = STS_ERR;
}
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(m);
bn_free(eb);
}
return result;
}
#endif
#if CP_RSA == BASIC || !defined(STRIP)
int cp_rsa_sig_basic(uint8_t *sig, int *sig_len, uint8_t *msg, int msg_len, int hash, rsa_t prv) {
bn_t m, eb;
int size, pad_len, result = STS_OK;
uint8_t h[MD_LEN];
if (prv == NULL || msg_len < 0) {
return STS_ERR;
}
pad_len = (!hash ? MD_LEN : msg_len);
#if CP_RSAPD == PKCS2
size = bn_bits(prv->n) - 1;
size = (size / 8) + (size % 8 > 0);
if (pad_len > (size - 2)) {
return STS_ERR;
}
#else
size = bn_size_bin(prv->n);
if (pad_len > (size - RSA_PAD_LEN)) {
return STS_ERR;
}
#endif
bn_null(m);
bn_null(eb);
TRY {
bn_new(m);
bn_new(eb);
bn_zero(m);
bn_zero(eb);
int operation = (!hash ? RSA_SIG : RSA_SIG_HASH);
#if CP_RSAPD == BASIC
if (pad_basic(eb, &pad_len, pad_len, size, operation) == STS_OK) {
#elif CP_RSAPD == PKCS1
if (pad_pkcs1(eb, &pad_len, pad_len, size, operation) == STS_OK) {
#elif CP_RSAPD == PKCS2
if (pad_pkcs2(eb, &pad_len, pad_len, size, operation) == STS_OK) {
#endif
if (!hash) {
md_map(h, msg, msg_len);
bn_read_bin(m, h, MD_LEN);
bn_add(eb, eb, m);
} else {
bn_read_bin(m, msg, msg_len);
bn_add(eb, eb, m);
}
#if CP_RSAPD == PKCS2
pad_pkcs2(eb, &pad_len, bn_bits(prv->n), size, RSA_SIG_FIN);
#endif
bn_mxp(eb, eb, prv->d, prv->n);
size = bn_size_bin(prv->n);
if (size <= *sig_len) {
memset(sig, 0, size);
bn_write_bin(sig, size, eb);
*sig_len = size;
} else {
result = STS_ERR;
}
} else {
result = STS_ERR;
}
}
CATCH_ANY {
THROW(ERR_CAUGHT);
}
FINALLY {
bn_free(m);
bn_free(eb);
}
return result;
}
#endif
#if CP_RSA == QUICK || !defined(STRIP)
int cp_rsa_sig_quick(uint8_t *sig, int *sig_len, uint8_t *msg, int msg_len, int hash, rsa_t prv) {
bn_t m, eb;
int pad_len, size, result = STS_OK;
uint8_t h[MD_LEN];
if (prv == NULL || msg_len < 0) {
return STS_ERR;
}
pad_len = (!hash ? MD_LEN : msg_len);
#if CP_RSAPD == PKCS2
size = bn_bits(prv->n) - 1;
size = (size / 8) + (size % 8 > 0);
if (pad_len > (size - 2)) {
return STS_ERR;
}
#else
size = bn_size_bin(prv->n);
if (pad_len > (size - RSA_PAD_LEN)) {
return STS_ERR;
}
#endif
bn_null(m);
bn_null(eb);
TRY {
bn_new(m);
bn_new(eb);
bn_zero(m);
bn_zero(eb);
int operation = (!hash ? RSA_SIG : RSA_SIG_HASH);
#if CP_RSAPD == BASIC
if (pad_basic(eb, &pad_len, pad_len, size, operation) == STS_OK) {
#elif CP_RSAPD == PKCS1
if (pad_pkcs1(eb, &pad_len, pad_len, size, operation) == STS_OK) {
#elif CP_RSAPD == PKCS2
if (pad_pkcs2(eb, &pad_len, pad_len, size, operation) == STS_OK) {
#endif
if (!hash) {
md_map(h, msg, msg_len);
bn_read_bin(m, h, MD_LEN);
bn_add(eb, eb, m);
} else {
bn_read_bin(m, msg, msg_len);
bn_add(eb, eb, m);
}
#if CP_RSAPD == PKCS2
pad_pkcs2(eb, &pad_len, bn_bits(prv->n), size, RSA_SIG_FIN);
#endif
bn_copy(m, eb);
/* m1 = c^dP mod p. */
bn_mxp(eb, eb, prv->dp, prv->p);
/* m2 = c^dQ mod q. */
bn_mxp(m, m, prv->dq, prv->q);
/* m1 = m1 - m2 mod p. */
bn_sub(eb, eb, m);
while (bn_sign(eb) == BN_NEG) {
bn_add(eb, eb, prv->p);
}
bn_mod(eb, eb, prv->p);
/* m1 = qInv(m1 - m2) mod p. */
bn_mul(eb, eb, prv->qi);
bn_mod(eb, eb, prv->p);
/* m = m2 + m1 * q. */
bn_mul(eb, eb, prv->q);
bn_add(eb, eb, m);
bn_mod(eb, eb, prv->n);
size = bn_size_bin(prv->n);
if (size <= *sig_len) {
memset(sig, 0, size);
bn_write_bin(sig, size, eb);
*sig_len = size;
} else {
result = STS_ERR;
}
} else {
result = STS_ERR;
}
}
CATCH_ANY {
THROW(ERR_CAUGHT);
}
FINALLY {
bn_free(m);
bn_free(eb);
}
return result;
}
#endif
int cp_rsa_ver(uint8_t *sig, int sig_len, uint8_t *msg, int msg_len, int hash, rsa_t pub) {
bn_t m, eb;
int size, pad_len, result;
uint8_t h1[MAX(msg_len, MD_LEN) + 8], h2[MAX(msg_len, MD_LEN)];
/* We suppose that the signature is invalid. */
result = 0;
if (pub == NULL || msg_len < 0) {
return 0;
}
pad_len = (!hash ? MD_LEN : msg_len);
#if CP_RSAPD == PKCS2
size = bn_bits(pub->n) - 1;
if (size % 8 == 0) {
size = size / 8 - 1;
} else {
size = bn_size_bin(pub->n);
}
if (pad_len > (size - 2)) {
return 0;
}
#else
size = bn_size_bin(pub->n);
if (pad_len > (size - RSA_PAD_LEN)) {
return 0;
}
#endif
bn_null(m);
bn_null(eb);
TRY {
bn_new(m);
bn_new(eb);
bn_read_bin(eb, sig, sig_len);
bn_mxp(eb, eb, pub->e, pub->n);
int operation = (!hash ? RSA_VER : RSA_VER_HASH);
#if CP_RSAPD == BASIC
if (pad_basic(eb, &pad_len, MD_LEN, size, operation) == STS_OK) {
#elif CP_RSAPD == PKCS1
if (pad_pkcs1(eb, &pad_len, MD_LEN, size, operation) == STS_OK) {
#elif CP_RSAPD == PKCS2
if (pad_pkcs2(eb, &pad_len, bn_bits(pub->n), size, operation) == STS_OK) {
#endif
#if CP_RSAPD == PKCS2
memset(h1, 0, 8);
if (!hash) {
md_map(h1 + 8, msg, msg_len);
md_map(h2, h1, MD_LEN + 8);
memset(h1, 0, MD_LEN);
bn_write_bin(h1, size - pad_len, eb);
/* Everything went ok, so signature status is changed. */
result = util_cmp_const(h1, h2, MD_LEN);
} else {
memcpy(h1 + 8, msg, msg_len);
md_map(h2, h1, MD_LEN + 8);
memset(h1, 0, msg_len);
bn_write_bin(h1, size - pad_len, eb);
/* Everything went ok, so signature status is changed. */
result = util_cmp_const(h1, h2, msg_len);
}
#else
memset(h1, 0, MAX(msg_len, MD_LEN));
bn_write_bin(h1, size - pad_len, eb);
if (!hash) {
md_map(h2, msg, msg_len);
/* Everything went ok, so signature status is changed. */
result = util_cmp_const(h1, h2, MD_LEN);
} else {
/* Everything went ok, so signature status is changed. */
result = util_cmp_const(h1, msg, msg_len);
}
#endif
result = (result == CMP_EQ ? 1 : 0);
} else {
result = 0;
}
}
CATCH_ANY {
result = 0;
}
FINALLY {
bn_free(m);
bn_free(eb);
}
return result;
}
int cp_bdpe_gen(bdpe_t pub, bdpe_t prv, dig_t block, int bits) {
bn_t t, r;
int result = STS_OK;
bn_null(t);
bn_null(r);
TRY {
bn_new(t);
bn_new(r);
prv->t = pub->t = block;
/* Make sure that block size is prime. */
bn_set_dig(t, block);
if (bn_is_prime_basic(t) == 0) {
THROW(ERR_NO_VALID);
}
/* Generate prime q such that gcd(block, (q - 1)) = 1. */
do {
bn_gen_prime(prv->q, bits / 2);
bn_sub_dig(prv->q, prv->q, 1);
bn_gcd_dig(t, prv->q, block);
bn_add_dig(prv->q, prv->q, 1);
} while (bn_cmp_dig(t, 1) != CMP_EQ);
/* Generate different primes p and q. */
do {
/* Compute p = block * (x * block + b) + 1, 0 < b < block random. */
bn_rand(prv->p, BN_POS, bits / 2 - 2 * util_bits_dig(block));
bn_mul_dig(prv->p, prv->p, block);
bn_rand(t, BN_POS, util_bits_dig(block));
bn_add_dig(prv->p, prv->p, t->dp[0]);
/* We know that block divides (p-1). */
bn_gcd_dig(t, prv->p, block);
bn_mul_dig(prv->p, prv->p, block);
bn_add_dig(prv->p, prv->p, 1);
} while (bn_cmp_dig(t, 1) != CMP_EQ || bn_is_prime(prv->p) == 0);
/* Compute t = (p-1)*(q-1). */
bn_sub_dig(prv->q, prv->q, 1);
bn_sub_dig(prv->p, prv->p, 1);
bn_mul(t, prv->p, prv->q);
bn_div_dig(t, t, block);
/* Restore factors p and q and compute n = p * q. */
bn_add_dig(prv->p, prv->p, 1);
bn_add_dig(prv->q, prv->q, 1);
bn_mul(pub->n, prv->p, prv->q);
bn_copy(prv->n, pub->n);
/* Select random y such that y^{(p-1)(q-1)}/block \neq 1 mod N. */
do {
bn_rand(pub->y, BN_POS, bits);
bn_mxp(r, pub->y, t, pub->n);
} while (bn_cmp_dig(r, 1) == CMP_EQ);
bn_copy(prv->y, pub->y);
}
CATCH_ANY {
result = STS_ERR;
}
FINALLY {
bn_free(t);
bn_free(r);
}
return result;
}
void bn_gen_prime_stron(bn_t a, int bits) {
dig_t i, j;
int found, k;
bn_t r, s, t;
bn_null(r);
bn_null(s);
bn_null(t);
TRY {
bn_new(r);
bn_new(s);
bn_new(t);
do {
do {
/* Generate two large primes r and s. */
bn_rand(s, BN_POS, bits / 2 - BN_DIGIT / 2);
bn_rand(t, BN_POS, bits / 2 - BN_DIGIT / 2);
} while (!bn_is_prime(s) || !bn_is_prime(t));
found = 1;
bn_rand(a, BN_POS, bits / 2 - bn_bits(t) - 1);
i = a->dp[0];
bn_dbl(t, t);
do {
/* Find first prime r = 2 * i * t + 1. */
bn_mul_dig(r, t, i);
bn_add_dig(r, r, 1);
i++;
if (bn_bits(r) > bits / 2 - 1) {
found = 0;
break;
}
} while (!bn_is_prime(r));
if (found == 0) {
continue;
}
/* Compute t = 2 * (s^(r-2) mod r) * s - 1. */
bn_sub_dig(t, r, 2);
#if BN_MOD != PMERS
bn_mxp(t, s, t, r);
#else
bn_exp(t, s, t, r);
#endif
bn_mul(t, t, s);
bn_dbl(t, t);
bn_sub_dig(t, t, 1);
k = bits - bn_bits(r);
k -= bn_bits(s);
bn_rand(a, BN_POS, k);
j = a->dp[0];
do {
/* Find first prime a = t + 2 * j * r * s. */
bn_mul(a, r, s);
bn_mul_dig(a, a, j);
bn_dbl(a, a);
bn_add(a, a, t);
j++;
if (bn_bits(a) > bits) {
found = 0;
break;
}
} while (!bn_is_prime(a));
} while (found == 0 && bn_bits(a) != bits);
}
CATCH_ANY {
THROW(ERR_CAUGHT);
}
FINALLY {
bn_free(r);
bn_free(s);
bn_free(t);
}
}
int bn_is_prime_solov(const bn_t a) {
bn_t t0, t1, t2;
int i, result;
bn_null(t0);
bn_null(t1);
bn_null(t2);
result = 1;
TRY {
bn_new(t0);
bn_new(t1);
bn_new(t2);
for (i = 0; i < 100; i++) {
/* Generate t0, 2 <= t0, <= a - 2. */
do {
bn_rand(t0, BN_POS, bn_bits(a));
bn_mod(t0, t0, a);
} while (bn_cmp_dig(t0, 2) == CMP_LT);
/* t2 = a - 1. */
bn_copy(t2, a);
bn_sub_dig(t2, t2, 1);
/* t1 = (a - 1)/2. */
bn_rsh(t1, t2, 1);
/* t1 = t0^(a - 1)/2 mod a. */
#if BN_MOD != PMERS
bn_mxp(t1, t0, t1, a);
#else
bn_exp(t1, t0, t1, a);
#endif
/* If t1 != 1 and t1 != n - 1 return 0 */
if (bn_cmp_dig(t1, 1) != CMP_EQ && bn_cmp(t1, t2) != CMP_EQ) {
result = 0;
break;
}
/* t2 = (t0|a). */
bn_smb_jac(t2, t0, a);
if (bn_sign(t2) == BN_NEG) {
bn_add(t2, t2, a);
}
/* If t1 != t2 (mod a) return 0. */
bn_mod(t1, t1, a);
bn_mod(t2, t2, a);
if (bn_cmp(t1, t2) != CMP_EQ) {
result = 0;
break;
}
}
}
CATCH_ANY {
result = 0;
THROW(ERR_CAUGHT);
}
FINALLY {
bn_free(t0);
bn_free(t1);
bn_free(t2);
}
return result;
}
int bn_is_prime_rabin(const bn_t a) {
bn_t t, n1, y, r;
int i, s, j, result, b, tests = 0;
tests = 0;
result = 1;
bn_null(t);
bn_null(n1);
bn_null(y);
bn_null(r);
if (bn_cmp_dig(a, 1) == CMP_EQ) {
return 0;
}
TRY {
/*
* These values are taken from Table 4.4 inside Handbook of Applied
* Cryptography.
*/
b = bn_bits(a);
if (b >= 1300) {
tests = 2;
} else if (b >= 850) {
tests = 3;
} else if (b >= 650) {
tests = 4;
} else if (b >= 550) {
tests = 5;
} else if (b >= 450) {
tests = 6;
} else if (b >= 400) {
tests = 7;
} else if (b >= 350) {
tests = 8;
} else if (b >= 300) {
tests = 9;
} else if (b >= 250) {
tests = 12;
} else if (b >= 200) {
tests = 15;
} else if (b >= 150) {
tests = 18;
} else {
tests = 27;
}
bn_new(t);
bn_new(n1);
bn_new(y);
bn_new(r);
/* r = (n - 1)/2^s. */
bn_sub_dig(n1, a, 1);
s = 0;
while (bn_is_even(n1)) {
s++;
bn_rsh(n1, n1, 1);
}
bn_lsh(r, n1, s);
for (i = 0; i < tests; i++) {
/* Fix the basis as the first few primes. */
bn_set_dig(t, primes[i]);
/* y = b^r mod a. */
#if BN_MOD != PMERS
bn_mxp(y, t, r, a);
#else
bn_exp(y, t, r, a);
#endif
if (bn_cmp_dig(y, 1) != CMP_EQ && bn_cmp(y, n1) != CMP_EQ) {
j = 1;
while ((j <= (s - 1)) && bn_cmp(y, n1) != CMP_EQ) {
bn_sqr(y, y);
bn_mod(y, y, a);
/* If y == 1 then composite. */
if (bn_cmp_dig(y, 1) == CMP_EQ) {
result = 0;
break;
}
++j;
}
/* If y != n1 then composite. */
if (bn_cmp(y, n1) != CMP_EQ) {
result = 0;
break;
}
}
}
}
CATCH_ANY {
result = 0;
THROW(ERR_CAUGHT);
}
FINALLY {
bn_free(r);
bn_free(y);
bn_free(n1);
bn_free(t);
}
return result;
}
