Attachment 694894 Details for Bug 908238 – gnutls 2.12.20 patch2

[patch] gnutls 2.12.20 patch2

gnutls-CVE-2013-1619-patch2.patch (text/plain), 3.52 KB, created by Michael Cronenworth on 2013-02-08 02:38:27 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Michael Cronenworth

Created: 2013-02-08 02:38:27 UTC

Size: 3.52 KB

patch

obsolete

>From 93b7fcfa3297a9123630704668b2946f602b910e Mon Sep 17 00:00:00 2001
>From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
>Date: Mon, 4 Feb 2013 09:39:42 +0100
>Subject: [PATCH] corrected fix
>
>---
> lib/gnutls_cipher.c |   29 ++++++++++++++++++++---------
> 1 files changed, 20 insertions(+), 9 deletions(-)
>
>diff --git a/lib/gnutls_cipher.c b/lib/gnutls_cipher.c
>index 7ac815d..2835121 100644
>--- a/lib/gnutls_cipher.c
>+++ b/lib/gnutls_cipher.c
>@@ -449,12 +449,22 @@ _gnutls_compressed2ciphertext (gnutls_session_t session,
> }
> 
> static void dummy_wait(record_parameters_st * params, gnutls_datum_t* plaintext, 
>-                       unsigned pad_failed, unsigned int pad, unsigned total)
>+                       unsigned pad_failed, unsigned int pad, unsigned total, int ver)
> {
>   /* this hack is only needed on CBC ciphers */
>   if (_gnutls_cipher_is_block (params->cipher_algorithm) == CIPHER_BLOCK)
>     {
>+      uint8_t MAC[MAX_HASH_SIZE];
>       unsigned len;
>+      digest_hd_st td;
>+      int ret;
>+
>+      ret = mac_init (&td, params->mac_algorithm,
>+                      params->read.mac_secret.data,
>+                      params->read.mac_secret.size, ver);
>+
>+      if (ret < 0)
>+        return;
> 
>       /* force an additional hash compression function evaluation to prevent timing 
>        * attacks that distinguish between wrong-mac + correct pad, from wrong-mac + incorrect pad.
>@@ -470,12 +480,14 @@ static void dummy_wait(record_parameters_st * params, gnutls_datum_t* plaintext,
> 	      if ((pad+total) % len > len-9 && total % len <= len-9) 
> 	        {
> 	          if (len < plaintext->size)
>-                    _gnutls_auth_cipher_add_auth (&params->read.cipher_state, plaintext->data, len);
>+                    mac_hash (&td, plaintext->data, len, ver);
>                   else
>-                    _gnutls_auth_cipher_add_auth (&params->read.cipher_state, plaintext->data, plaintext->size);
>+                    mac_hash (&td, plaintext->data, plaintext->size, ver);
>                 }
>             }
>         }
>+
>+      mac_deinit (&td, MAC, ver);
>     }
> }
> 
>@@ -491,12 +503,12 @@ _gnutls_ciphertext2compressed (gnutls_session_t session,
> {
>   uint8_t MAC[MAX_HASH_SIZE];
>   uint16_t c_length;
>-  uint8_t pad;
>+  unsigned int pad = 0;
>   int length;
>   uint16_t blocksize;
>   int ret, i, pad_failed = 0;
>   opaque preamble[PREAMBLE_SIZE];
>-  int preamble_size;
>+  int preamble_size = 0;
>   int ver = gnutls_protocol_get_version (session);
>   int hash_size = _gnutls_hash_get_algo_len (params->mac_algorithm);
> 
>@@ -558,14 +570,13 @@ _gnutls_ciphertext2compressed (gnutls_session_t session,
>       if (_gnutls_version_has_variable_padding (ver) && pad_failed == 0)
>         for (i = 2; i < pad; i++)
>           {
>-            if (ciphertext.data[ciphertext.size - i] !=
>-                ciphertext.data[ciphertext.size - 1])
>+            if (ciphertext.data[ciphertext.size - i] != pad)
>               pad_failed = GNUTLS_E_DECRYPTION_FAILED;
>           }
>           
>       if (pad_failed)
>         pad = 0;
>-      length = ciphertext.size - hash_size - pad;
>+      length = ciphertext.size - hash_size - pad - 1;
> 
>       break;
>     default:
>@@ -610,7 +621,7 @@ _gnutls_ciphertext2compressed (gnutls_session_t session,
>     {
>       gnutls_datum_t compressed = {compress_data, compress_size};
>       /* HMAC was not the same. */
>-      dummy_wait(params, &compressed, pad_failed, pad, length+preamble_size);
>+      dummy_wait(params, &compressed, pad_failed, pad, length+preamble_size, ver);
> 
>       gnutls_assert ();
>       return GNUTLS_E_DECRYPTION_FAILED;
>-- 
>1.7.1
>

Actions: View | Diff

Attachments on bug 908238: 694893 | 694894