Don't allocate r/s in DSA_SIG and ECDSA_SIG

[openssl.git] / crypto / dsa / dsa_key.c

diff --git a/crypto/dsa/dsa_key.c b/crypto/dsa/dsa_key.c
index 19d21eacf72f1dddaf2c8314891d357247cc099c..31442b1cff17ac439448e214489d2d6aa28afa36 100644 (file)
--- a/crypto/dsa/dsa_key.c
+++ b/crypto/dsa/dsa_key.c
@@ -1,67 +1,17 @@
-/* crypto/dsa/dsa_key.c */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
+/*
+ * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
  *
- * This package is an SSL implementation written
- * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
- *
- * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to.  The following conditions
- * apply to all code found in this distribution, be it the RC4, RSA,
- * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
- * included with this distribution is covered by the same copyright terms
- * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- *
- * Copyright remains Eric Young's, and as such any Copyright notices in
- * the code are not to be removed.
- * If this package is used in a product, Eric Young should be given attribution
- * as the author of the parts of the library used.
- * This can be in the form of a textual message at program startup or
- * in documentation (online or textual) provided with the package.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *    "This product includes cryptographic software written by
- *     Eric Young (eay@cryptsoft.com)"
- *    The word 'cryptographic' can be left out if the rouines from the library
- *    being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from
- *    the apps directory (application code) you must include an acknowledgement:
- *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- *
- * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * The licence and distribution terms for any publically available version or
- * derivative of this code cannot be changed.  i.e. this code cannot simply be
- * copied and put under another distribution licence
- * [including the GNU Public Licence.]
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
  */
 
 #include <stdio.h>
 #include <time.h>
 #include "internal/cryptlib.h"
 #include <openssl/bn.h>
-#include <openssl/dsa.h>
-#include <openssl/rand.h>
+#include "dsa_locl.h"
 
 static int dsa_builtin_keygen(DSA *dsa);
 
@@ -99,22 +49,18 @@ static int dsa_builtin_keygen(DSA *dsa)
         pub_key = dsa->pub_key;
 
     {
-        BIGNUM *local_prk = NULL;
-        BIGNUM *prk;
+        BIGNUM *prk = BN_new();
 
-        if ((dsa->flags & DSA_FLAG_NO_EXP_CONSTTIME) == 0) {
-            local_prk = prk = BN_new();
-            if (!local_prk)
-                goto err;
-            BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
-        } else
-            prk = priv_key;
+        if (prk == NULL)
+            goto err;
+        BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
 
         if (!BN_mod_exp(pub_key, dsa->g, prk, dsa->p, ctx)) {
-            BN_free(local_prk);
+            BN_free(prk);
             goto err;
         }
-        BN_free(local_prk);
+        /* We MUST free prk before any further use of priv_key */
+        BN_free(prk);
     }
 
     dsa->priv_key = priv_key;