const int vko_dgst_nid)
{
unsigned char *databuf = NULL;
- BIGNUM *UKM = NULL, *p = NULL, *order = NULL, *X = NULL, *Y = NULL, *cofactor = NULL;
- const BIGNUM *key = EC_KEY_get0_private_key(priv_key);
- EC_POINT *pnt = EC_POINT_new(EC_KEY_get0_group(priv_key));
- BN_CTX *ctx = BN_CTX_secure_new();
+ BIGNUM *scalar = NULL, *order = NULL, *X = NULL, *Y = NULL;
+ const EC_GROUP *grp = NULL;
+ EC_POINT *pnt = NULL;
+ BN_CTX *ctx = NULL;
EVP_MD_CTX *mdctx = NULL;
const EVP_MD *md = NULL;
int buf_len, half_len;
int ret = 0;
- if (!ctx) {
+ if ((ctx = BN_CTX_secure_new()) == NULL) {
GOSTerr(GOST_F_VKO_COMPUTE_KEY, ERR_R_MALLOC_FAILURE);
return 0;
}
goto err;
}
- UKM = BN_lebin2bn(ukm, ukm_size, NULL);
- p = BN_CTX_get(ctx);
- order = BN_CTX_get(ctx);
- cofactor = BN_CTX_get(ctx);
+ grp = EC_KEY_get0_group(priv_key);
+ scalar = BN_CTX_get(ctx);
+ order = BN_CTX_get(ctx);
X = BN_CTX_get(ctx);
- Y = BN_CTX_get(ctx);
- EC_GROUP_get_order(EC_KEY_get0_group(priv_key), order, ctx);
- EC_GROUP_get_cofactor(EC_KEY_get0_group(priv_key), cofactor, ctx);
- BN_mod_mul(UKM, UKM, cofactor, order, ctx);
- BN_mod_mul(p, key, UKM, order, ctx);
- if (!EC_POINT_mul(EC_KEY_get0_group(priv_key), pnt, NULL, pub_key, p, ctx)) {
+
+ if ((Y = BN_CTX_get(ctx)) == NULL
+ || (pnt = EC_POINT_new(grp)) == NULL
+ || BN_lebin2bn(ukm, ukm_size, scalar) == NULL
+ || !BN_mod_mul(scalar, scalar, EC_KEY_get0_private_key(priv_key),
+ EC_GROUP_get0_order(grp), ctx))
+ goto err;
+
+ /* these two curves have cofactor 4; the rest have cofactor 1 */
+ switch (EC_GROUP_get_curve_name(grp)) {
+ case NID_id_tc26_gost_3410_2012_256_paramSetA:
+ case NID_id_tc26_gost_3410_2012_512_paramSetC:
+ if (!BN_lshift(scalar, scalar, 2))
+ goto err;
+ break;
+ }
+
+ if (!gost_ec_point_mul(grp, pnt, NULL, pub_key, scalar, ctx)) {
GOSTerr(GOST_F_VKO_COMPUTE_KEY, GOST_R_ERROR_POINT_MUL);
goto err;
}
- if (!EC_POINT_get_affine_coordinates(EC_KEY_get0_group(priv_key),
- pnt, X, Y, ctx)) {
- GOSTerr(GOST_F_VKO_COMPUTE_KEY, ERR_R_EC_LIB);
- goto err;
+ if (!EC_POINT_get_affine_coordinates(grp, pnt, X, Y, ctx) ||
+ !EC_GROUP_get_order(grp, order, ctx)) {
+ GOSTerr(GOST_F_VKO_COMPUTE_KEY, ERR_R_EC_LIB);
+ goto err;
}
half_len = BN_num_bytes(order);
buf_len = 2 * half_len;
- databuf = OPENSSL_zalloc(buf_len);
- if (!databuf) {
+ if ((databuf = OPENSSL_malloc(buf_len)) == NULL) {
GOSTerr(GOST_F_VKO_COMPUTE_KEY, ERR_R_MALLOC_FAILURE);
goto err;
}
/*
* Serialize elliptic curve point same way as we do it when saving key
*/
- store_bignum(Y, databuf, half_len);
- store_bignum(X, databuf + half_len, half_len);
- /* And reverse byte order of whole buffer */
- BUF_reverse(databuf, NULL, buf_len);
+ if (BN_bn2lebinpad(X, databuf, half_len) != half_len
+ || BN_bn2lebinpad(Y, databuf + half_len, half_len) != half_len)
+ goto err;
- mdctx = EVP_MD_CTX_new();
- if (!mdctx) {
+ if ((mdctx = EVP_MD_CTX_new()) == NULL) {
GOSTerr(GOST_F_VKO_COMPUTE_KEY, ERR_R_MALLOC_FAILURE);
goto err;
}
ret = (EVP_MD_size(md) > 0) ? EVP_MD_size(md) : 0;
err:
- BN_free(UKM);
BN_CTX_end(ctx);
BN_CTX_free(ctx);
-
EC_POINT_free(pnt);
-
EVP_MD_CTX_free(mdctx);
-
OPENSSL_free(databuf);
return ret;