cppcheck: Variable is reassigned a value before the old one has been used.

[openssl-gost/engine.git] / gost_ec_keyx.c

diff --git a/gost_ec_keyx.c b/gost_ec_keyx.c
index a95df330f2546b757566b20e02666ab99ee6267b..de52dec2c2a703ebb4dfa50535e8b5c83cf1e154 100644 (file)
--- a/gost_ec_keyx.c
+++ b/gost_ec_keyx.c
@@ -18,16 +18,16 @@
 #include "gost_lcl.h"
 
 /* Implementation of CryptoPro VKO 34.10-2001/2012 algorithm */
-static int VKO_compute_key(unsigned char *shared_key,
-                           const EC_POINT *pub_key, const EC_KEY *priv_key,
-                           const unsigned char *ukm, const size_t ukm_size,
-                           const int vko_dgst_nid)
+int VKO_compute_key(unsigned char *shared_key,
+                    const EC_POINT *pub_key, const EC_KEY *priv_key,
+                    const unsigned char *ukm, const size_t ukm_size,
+                    const int vko_dgst_nid)
 {
     unsigned char *databuf = NULL;
-    BIGNUM *UKM = NULL, *p = NULL, *order = NULL, *X = NULL, *Y = 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_new();
+    BN_CTX *ctx = BN_CTX_secure_new();
     EVP_MD_CTX *mdctx = NULL;
     const EVP_MD *md = NULL;
     int buf_len, half_len;
@@ -45,19 +45,25 @@ static int VKO_compute_key(unsigned char *shared_key,
         goto err;
     }
 
-    UKM = hashsum2bn(ukm, ukm_size);
+    UKM = BN_lebin2bn(ukm, ukm_size, NULL);
     p = BN_CTX_get(ctx);
     order = BN_CTX_get(ctx);
+               cofactor = 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)) {
         GOSTerr(GOST_F_VKO_COMPUTE_KEY, GOST_R_ERROR_POINT_MUL);
         goto err;
     }
-    EC_POINT_get_affine_coordinates(EC_KEY_get0_group(priv_key),
-                                        pnt, X, Y, ctx);
+    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;
+    }
 
     half_len = BN_num_bytes(order);
     buf_len = 2 * half_len;
@@ -146,7 +152,6 @@ static int gost_keg(const unsigned char *ukm_source, int pkey_nid,
 
             OPENSSL_cleanse(tmpkey, 32);
             return (keylen) ? keylen : 0;
-            break;
         }
     default:
         return 0;
@@ -251,13 +256,14 @@ static int pkey_GOST_ECcp_encrypt(EVP_PKEY_CTX *pctx, unsigned char *out,
     EVP_PKEY *sec_key = EVP_PKEY_CTX_get0_peerkey(pctx);
     if (data->shared_ukm) {
         memcpy(ukm, data->shared_ukm, 8);
-    } else if (out) {
-
+    } else {
         if (RAND_bytes(ukm, 8) <= 0) {
             GOSTerr(GOST_F_PKEY_GOST_ECCP_ENCRYPT, GOST_R_RNG_ERROR);
             return 0;
         }
     }
+    if (!param)
+        goto err;
     /* Check for private key in the peer_key of context */
     if (sec_key) {
         key_is_ephemeral = 0;
@@ -279,10 +285,6 @@ static int pkey_GOST_ECcp_encrypt(EVP_PKEY_CTX *pctx, unsigned char *out,
             }
         }
     }
-    if (!get_gost_engine_param(GOST_PARAM_CRYPT_PARAMS)
-        && param == gost_cipher_list) {
-        param = gost_cipher_list;
-    }
     if (out) {
         int dgst_nid = NID_undef;
         EVP_PKEY_get_default_digest_nid(pubk, &dgst_nid);
@@ -335,9 +337,11 @@ static int pkey_GOST_ECcp_encrypt(EVP_PKEY_CTX *pctx, unsigned char *out,
     }
     if ((*out_len = i2d_GOST_KEY_TRANSPORT(gkt, out ? &out : NULL)) > 0)
         ret = 1;
+    OPENSSL_cleanse(shared_key, sizeof(shared_key));
     GOST_KEY_TRANSPORT_free(gkt);
     return ret;
  err:
+    OPENSSL_cleanse(shared_key, sizeof(shared_key));
     if (key_is_ephemeral)
         EVP_PKEY_free(sec_key);
     GOST_KEY_TRANSPORT_free(gkt);
@@ -441,6 +445,7 @@ static int pkey_gost2018_encrypt(EVP_PKEY_CTX *pctx, unsigned char *out,
     if ((*out_len = i2d_PSKeyTransport_gost(pst, out ? &out : NULL)) > 0)
         ret = 1;
  err:
+    OPENSSL_cleanse(expkeys, sizeof(expkeys));
     if (key_is_ephemeral)
       EVP_PKEY_free(sec_key);
 
@@ -547,6 +552,7 @@ static int pkey_GOST_ECcp_decrypt(EVP_PKEY_CTX *pctx, unsigned char *key,
 
     ret = 1;
  err:
+    OPENSSL_cleanse(sharedKey, sizeof(sharedKey));
     EVP_PKEY_free(eph_key);
     GOST_KEY_TRANSPORT_free(gkt);
     return ret;
@@ -627,6 +633,7 @@ static int pkey_gost2018_decrypt(EVP_PKEY_CTX *pctx, unsigned char *key,
 
     ret = 1;
  err:
+    OPENSSL_cleanse(expkeys, sizeof(expkeys));
     EVP_PKEY_free(eph_key);
     PSKeyTransport_gost_free(pst);
     return ret;