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;
}
static void tests_relic_ecdh(void)
{
/* The following is an example for doing an elliptic-curve Diffie-Hellman
key exchange.
*/
/* Select an elliptic curve configuration */
if (ec_param_set_any() == STS_OK) {
#if (TEST_RELIC_SHOW_OUTPUT == 1)
ec_param_print();
#endif
bn_t privateA;
ec_t publicA;
uint8_t sharedKeyA[MD_LEN];
bn_t privateB;
ec_t publicB;
uint8_t sharedKeyB[MD_LEN];
bn_null(privateA);
ec_null(publicA);
bn_new(privateA);
ec_new(publicA);
bn_null(privateB);
ec_null(publicB);
bn_new(privateB);
ec_new(publicB);
/* User A generates private/public key pair */
TEST_ASSERT_EQUAL_INT(STS_OK, cp_ecdh_gen(privateA, publicA));
#if (TEST_RELIC_SHOW_OUTPUT == 1)
printf("User A\n");
printf("======\n");
printf("private key: ");
bn_print(privateA);
printf("\npublic key: ");
ec_print(publicA);
printf("\n");
#endif
/* User B generates private/public key pair */
TEST_ASSERT_EQUAL_INT(STS_OK, cp_ecdh_gen(privateB, publicB));
#if (TEST_RELIC_SHOW_OUTPUT == 1)
printf("User B\n");
printf("======\n");
printf("private key: ");
bn_print(privateB);
printf("\npublic key: ");
ec_print(publicB);
printf("\n");
#endif
/* In a protocol you would exchange the public keys now */
/* User A calculates shared secret */
TEST_ASSERT_EQUAL_INT(STS_OK, cp_ecdh_key(sharedKeyA, MD_LEN, privateA, publicB));
#if (TEST_RELIC_SHOW_OUTPUT == 1)
printf("\nshared key computed by user A: ");
print_mem(sharedKeyA, MD_LEN);
#endif
/* User B calculates shared secret */
TEST_ASSERT_EQUAL_INT(STS_OK, cp_ecdh_key(sharedKeyB, MD_LEN, privateB, publicA));
#if (TEST_RELIC_SHOW_OUTPUT == 1)
printf("\nshared key computed by user B: ");
print_mem(sharedKeyB, MD_LEN);
#endif
/* The secrets should be the same now */
TEST_ASSERT_EQUAL_INT(CMP_EQ, util_cmp_const(sharedKeyA, sharedKeyB, MD_LEN));
bn_free(privateA);
ec_free(publicA);
bn_free(privateB);
ec_free(publicB);
#if (TEST_RELIC_SHOW_OUTPUT == 1)
printf("\nRELIC EC-DH test successful\n");
#endif
}
}
