#include "internal/sm2.h"
#include "internal/sm2err.h"
+#include "internal/ec_int.h" /* ecdh_KDF_X9_63() */
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/bn.h>
IMPLEMENT_ASN1_FUNCTIONS(SM2_Ciphertext)
-static size_t EC_field_size(const EC_GROUP *group)
+static size_t ec_field_size(const EC_GROUP *group)
{
/* Is there some simpler way to do this? */
BIGNUM *p = BN_new();
if (p == NULL || a == NULL || b == NULL)
goto done;
- EC_GROUP_get_curve_GFp(group, p, a, b, NULL);
+ if (!EC_GROUP_get_curve(group, p, a, b, NULL))
+ goto done;
field_size = (BN_num_bits(p) + 7) / 8;
done:
return field_size;
}
-int SM2_plaintext_size(const EC_KEY *key, const EVP_MD *digest, size_t msg_len,
+int sm2_plaintext_size(const EC_KEY *key, const EVP_MD *digest, size_t msg_len,
size_t *pt_size)
{
- const size_t field_size = EC_field_size(EC_KEY_get0_group(key));
+ const size_t field_size = ec_field_size(EC_KEY_get0_group(key));
const int md_size = EVP_MD_size(digest);
size_t overhead;
if (md_size < 0) {
- SM2err(SM2_F_SM2_ENCRYPT, SM2_R_INVALID_DIGEST);
+ SM2err(SM2_F_SM2_PLAINTEXT_SIZE, SM2_R_INVALID_DIGEST);
return 0;
}
if (field_size == 0) {
- SM2err(SM2_F_SM2_ENCRYPT, SM2_R_INVALID_FIELD);
+ SM2err(SM2_F_SM2_PLAINTEXT_SIZE, SM2_R_INVALID_FIELD);
return 0;
}
overhead = 10 + 2 * field_size + (size_t)md_size;
- if(msg_len <= overhead) {
- SM2err(SM2_F_SM2_ENCRYPT, SM2_R_INVALID_ENCODING);
+ if (msg_len <= overhead) {
+ SM2err(SM2_F_SM2_PLAINTEXT_SIZE, SM2_R_INVALID_ENCODING);
return 0;
}
return 1;
}
-int SM2_ciphertext_size(const EC_KEY *key, const EVP_MD *digest, size_t msg_len,
+int sm2_ciphertext_size(const EC_KEY *key, const EVP_MD *digest, size_t msg_len,
size_t *ct_size)
{
- const size_t field_size = EC_field_size(EC_KEY_get0_group(key));
+ const size_t field_size = ec_field_size(EC_KEY_get0_group(key));
const int md_size = EVP_MD_size(digest);
+ size_t sz;
if (field_size == 0 || md_size < 0)
return 0;
- *ct_size = 10 + 2 * field_size + (size_t)md_size + msg_len;
+ /* Integer and string are simple type; set constructed = 0, means primitive and definite length encoding. */
+ sz = 2 * ASN1_object_size(0, field_size + 1, V_ASN1_INTEGER)
+ + ASN1_object_size(0, md_size, V_ASN1_OCTET_STRING)
+ + ASN1_object_size(0, msg_len, V_ASN1_OCTET_STRING);
+ /* Sequence is structured type; set constructed = 1, means constructed and definite length encoding. */
+ *ct_size = ASN1_object_size(1, sz, V_ASN1_SEQUENCE);
+
return 1;
}
-int SM2_encrypt(const EC_KEY *key,
+int sm2_encrypt(const EC_KEY *key,
const EVP_MD *digest,
const uint8_t *msg,
size_t msg_len, uint8_t *ciphertext_buf, size_t *ciphertext_len)
uint8_t *msg_mask = NULL;
uint8_t *x2y2 = NULL;
uint8_t *C3 = NULL;
- const size_t field_size = EC_field_size(group);
- const size_t C3_size = EVP_MD_size(digest);
+ size_t field_size;
+ const int C3_size = EVP_MD_size(digest);
/* NULL these before any "goto done" */
ctext_struct.C2 = NULL;
ctext_struct.C3 = NULL;
- if (hash == NULL
- || group == NULL
- || order == NULL
- || P == NULL
- || field_size == 0
- || C3_size == 0) {
+ if (hash == NULL || C3_size <= 0) {
+ SM2err(SM2_F_SM2_ENCRYPT, ERR_R_INTERNAL_ERROR);
+ goto done;
+ }
+
+ field_size = ec_field_size(group);
+ if (field_size == 0) {
SM2err(SM2_F_SM2_ENCRYPT, ERR_R_INTERNAL_ERROR);
goto done;
}
}
if (!EC_POINT_mul(group, kG, k, NULL, NULL, ctx)
- || !EC_POINT_get_affine_coordinates_GFp(group, kG, x1, y1, ctx)
+ || !EC_POINT_get_affine_coordinates(group, kG, x1, y1, ctx)
|| !EC_POINT_mul(group, kP, NULL, P, k, ctx)
- || !EC_POINT_get_affine_coordinates_GFp(group, kP, x2, y2, ctx)) {
+ || !EC_POINT_get_affine_coordinates(group, kP, x2, y2, ctx)) {
SM2err(SM2_F_SM2_ENCRYPT, ERR_R_EC_LIB);
goto done;
}
}
/* X9.63 with no salt happens to match the KDF used in SM2 */
- if (!ECDH_KDF_X9_62(msg_mask, msg_len, x2y2, 2 * field_size, NULL, 0,
+ if (!ecdh_KDF_X9_63(msg_mask, msg_len, x2y2, 2 * field_size, NULL, 0,
digest)) {
SM2err(SM2_F_SM2_ENCRYPT, ERR_R_EVP_LIB);
goto done;
return rc;
}
-int SM2_decrypt(const EC_KEY *key,
+int sm2_decrypt(const EC_KEY *key,
const EVP_MD *digest,
const uint8_t *ciphertext,
size_t ciphertext_len, uint8_t *ptext_buf, size_t *ptext_len)
{
int rc = 0;
int i;
-
BN_CTX *ctx = NULL;
const EC_GROUP *group = EC_KEY_get0_group(key);
EC_POINT *C1 = NULL;
struct SM2_Ciphertext_st *sm2_ctext = NULL;
BIGNUM *x2 = NULL;
BIGNUM *y2 = NULL;
-
uint8_t *x2y2 = NULL;
uint8_t *computed_C3 = NULL;
-
- const size_t field_size = EC_field_size(group);
+ const size_t field_size = ec_field_size(group);
const int hash_size = EVP_MD_size(digest);
-
uint8_t *msg_mask = NULL;
const uint8_t *C2 = NULL;
const uint8_t *C3 = NULL;
int msg_len = 0;
EVP_MD_CTX *hash = NULL;
- if (field_size == 0 || hash_size == 0)
+ if (field_size == 0 || hash_size <= 0)
goto done;
memset(ptext_buf, 0xFF, *ptext_len);
sm2_ctext = d2i_SM2_Ciphertext(NULL, &ciphertext, ciphertext_len);
- if (sm2_ctext == NULL)
- {
+ if (sm2_ctext == NULL) {
SM2err(SM2_F_SM2_DECRYPT, SM2_R_ASN1_ERROR);
goto done;
- }
+ }
- if (sm2_ctext->C3->length != hash_size)
- {
+ if (sm2_ctext->C3->length != hash_size) {
SM2err(SM2_F_SM2_DECRYPT, SM2_R_INVALID_ENCODING);
goto done;
- }
+ }
C2 = sm2_ctext->C2->data;
C3 = sm2_ctext->C3->data;
msg_len = sm2_ctext->C2->length;
ctx = BN_CTX_new();
- if (ctx == NULL)
- {
+ if (ctx == NULL) {
SM2err(SM2_F_SM2_DECRYPT, ERR_R_MALLOC_FAILURE);
goto done;
- }
+ }
BN_CTX_start(ctx);
x2 = BN_CTX_get(ctx);
y2 = BN_CTX_get(ctx);
- if(y2 == NULL)
- {
+ if (y2 == NULL) {
SM2err(SM2_F_SM2_DECRYPT, ERR_R_BN_LIB);
goto done;
- }
+ }
msg_mask = OPENSSL_zalloc(msg_len);
x2y2 = OPENSSL_zalloc(2 * field_size);
computed_C3 = OPENSSL_zalloc(hash_size);
- if(msg_mask == NULL || x2y2 == NULL || computed_C3 == NULL)
- {
+ if (msg_mask == NULL || x2y2 == NULL || computed_C3 == NULL) {
SM2err(SM2_F_SM2_DECRYPT, ERR_R_MALLOC_FAILURE);
goto done;
- }
+ }
C1 = EC_POINT_new(group);
- if (C1 == NULL)
- {
+ if (C1 == NULL) {
SM2err(SM2_F_SM2_DECRYPT, ERR_R_MALLOC_FAILURE);
goto done;
- }
-
- if (EC_POINT_set_affine_coordinates_GFp
- (group, C1, sm2_ctext->C1x, sm2_ctext->C1y, ctx) == 0)
- {
- SM2err(SM2_F_SM2_DECRYPT, ERR_R_EC_LIB);
- goto done;
- }
-
- if (EC_POINT_mul(group, C1, NULL, C1, EC_KEY_get0_private_key(key), ctx) ==
- 0)
- {
- SM2err(SM2_F_SM2_DECRYPT, ERR_R_EC_LIB);
- goto done;
- }
+ }
- if (EC_POINT_get_affine_coordinates_GFp(group, C1, x2, y2, ctx) == 0)
- {
+ if (!EC_POINT_set_affine_coordinates(group, C1, sm2_ctext->C1x,
+ sm2_ctext->C1y, ctx)
+ || !EC_POINT_mul(group, C1, NULL, C1, EC_KEY_get0_private_key(key),
+ ctx)
+ || !EC_POINT_get_affine_coordinates(group, C1, x2, y2, ctx)) {
SM2err(SM2_F_SM2_DECRYPT, ERR_R_EC_LIB);
goto done;
- }
-
- BN_bn2binpad(x2, x2y2, field_size);
- BN_bn2binpad(y2, x2y2 + field_size, field_size);
+ }
- if (ECDH_KDF_X9_62(msg_mask, msg_len, x2y2, 2 * field_size, NULL, 0, digest)
- == 0)
+ if (BN_bn2binpad(x2, x2y2, field_size) < 0
+ || BN_bn2binpad(y2, x2y2 + field_size, field_size) < 0
+ || !ecdh_KDF_X9_63(msg_mask, msg_len, x2y2, 2 * field_size, NULL, 0,
+ digest)) {
+ SM2err(SM2_F_SM2_DECRYPT, ERR_R_INTERNAL_ERROR);
goto done;
+ }
for (i = 0; i != msg_len; ++i)
ptext_buf[i] = C2[i] ^ msg_mask[i];
hash = EVP_MD_CTX_new();
-
- if (hash == NULL)
- {
+ if (hash == NULL) {
SM2err(SM2_F_SM2_DECRYPT, ERR_R_MALLOC_FAILURE);
goto done;
- }
-
- if (EVP_DigestInit(hash, digest) == 0)
- {
- SM2err(SM2_F_SM2_DECRYPT, ERR_R_EVP_LIB);
- goto done;
- }
-
- if (EVP_DigestUpdate(hash, x2y2, field_size) == 0)
- {
- SM2err(SM2_F_SM2_DECRYPT, ERR_R_EVP_LIB);
- goto done;
- }
-
- if (EVP_DigestUpdate(hash, ptext_buf, msg_len) == 0)
- {
- SM2err(SM2_F_SM2_DECRYPT, ERR_R_EVP_LIB);
- goto done;
- }
-
- if (EVP_DigestUpdate(hash, x2y2 + field_size, field_size) == 0)
- {
- SM2err(SM2_F_SM2_DECRYPT, ERR_R_EVP_LIB);
- goto done;
- }
+ }
- if (EVP_DigestFinal(hash, computed_C3, NULL) == 0)
- {
+ if (!EVP_DigestInit(hash, digest)
+ || !EVP_DigestUpdate(hash, x2y2, field_size)
+ || !EVP_DigestUpdate(hash, ptext_buf, msg_len)
+ || !EVP_DigestUpdate(hash, x2y2 + field_size, field_size)
+ || !EVP_DigestFinal(hash, computed_C3, NULL)) {
SM2err(SM2_F_SM2_DECRYPT, ERR_R_EVP_LIB);
goto done;
- }
+ }
- if (memcmp(computed_C3, C3, hash_size) != 0)
+ if (CRYPTO_memcmp(computed_C3, C3, hash_size) != 0) {
+ SM2err(SM2_F_SM2_DECRYPT, SM2_R_INVALID_DIGEST);
goto done;
+ }
rc = 1;
*ptext_len = msg_len;
done:
-
if (rc == 0)
memset(ptext_buf, 0, *ptext_len);