Mitigate cache-timing attack in CBC mode. This is done by implementing

[openssl.git] / crypto / evp / p5_crpt.c

diff --git a/crypto/evp/p5_crpt.c b/crypto/evp/p5_crpt.c
index 27a8286489fd9a1bc93aa4289edf2c8f43ee0d07..c0dfb7de373037148fb233020fee72bc2978e598 100644 (file)
--- a/crypto/evp/p5_crpt.c
+++ b/crypto/evp/p5_crpt.c
@@ -110,7 +110,8 @@ int PKCS5_PBE_keyivgen(EVP_CIPHER_CTX *cctx, const char *pass, int passlen,
        int i;
        PBEPARAM *pbe;
        int saltlen, iter;
-       unsigned char *salt, *pbuf;
+       unsigned char *salt;
+       const unsigned char *pbuf;
 
        /* Extract useful info from parameter */
        pbuf = param->value.sequence->data;
@@ -140,12 +141,14 @@ int PKCS5_PBE_keyivgen(EVP_CIPHER_CTX *cctx, const char *pass, int passlen,
                EVP_DigestFinal_ex (&ctx, md_tmp, NULL);
        }
        EVP_MD_CTX_cleanup(&ctx);
+       OPENSSL_assert(EVP_CIPHER_key_length(cipher) <= (int)sizeof(md_tmp));
        memcpy(key, md_tmp, EVP_CIPHER_key_length(cipher));
+       OPENSSL_assert(EVP_CIPHER_iv_length(cipher) <= 16);
        memcpy(iv, md_tmp + (16 - EVP_CIPHER_iv_length(cipher)),
                                                 EVP_CIPHER_iv_length(cipher));
        EVP_CipherInit_ex(cctx, cipher, NULL, key, iv, en_de);
-       memset(md_tmp, 0, EVP_MAX_MD_SIZE);
-       memset(key, 0, EVP_MAX_KEY_LENGTH);
-       memset(iv, 0, EVP_MAX_IV_LENGTH);
+       OPENSSL_cleanse(md_tmp, EVP_MAX_MD_SIZE);
+       OPENSSL_cleanse(key, EVP_MAX_KEY_LENGTH);
+       OPENSSL_cleanse(iv, EVP_MAX_IV_LENGTH);
        return 1;
 }