openssl/patches/openssl.git-96db902.patch

   1 From: Dr. Stephen Henson <steve@openssl.org>
   2 Date: Sat, 5 Apr 2014 23:51:06 +0000 (+0100)
   3 Subject: Add heartbeat extension bounds check.
   4 X-Git-Tag: OpenSSL_1_0_1g~3
   5 X-Git-Url: http://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff_plain;h=96db902
   6
   7 Add heartbeat extension bounds check.
   8
   9 A missing bounds check in the handling of the TLS heartbeat extension
  10 can be used to reveal up to 64k of memory to a connected client or
  11 server.
  12
  13 Thanks for Neel Mehta of Google Security for discovering this bug and to
  14 Adam Langley <agl@chromium.org> and Bodo Moeller <bmoeller@acm.org> for
  15 preparing the fix (CVE-2014-0160)
  16 ---
  17
  18 diff --git a/ssl/d1_both.c b/ssl/d1_both.c
  19 index 7a5596a..2e8cf68 100644
  20 --- a/ssl/d1_both.c
  21 +++ b/ssl/d1_both.c
  22 @@ -1459,26 +1459,36 @@ dtls1_process_heartbeat(SSL *s)
  23         unsigned int payload;
  24         unsigned int padding = 16; /* Use minimum padding */
  25
  26 -       /* Read type and payload length first */
  27 -       hbtype = *p++;
  28 -       n2s(p, payload);
  29 -       pl = p;
  30 -
  31         if (s->msg_callback)
  32                 s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT,
  33                         &s->s3->rrec.data[0], s->s3->rrec.length,
  34                         s, s->msg_callback_arg);
  35
  36 +       /* Read type and payload length first */
  37 +       if (1 + 2 + 16 > s->s3->rrec.length)
  38 +               return 0; /* silently discard */
  39 +       hbtype = *p++;
  40 +       n2s(p, payload);
  41 +       if (1 + 2 + payload + 16 > s->s3->rrec.length)
  42 +               return 0; /* silently discard per RFC 6520 sec. 4 */
  43 +       pl = p;
  44 +
  45         if (hbtype == TLS1_HB_REQUEST)
  46                 {
  47                 unsigned char *buffer, *bp;
  48 +               unsigned int write_length = 1 /* heartbeat type */ +
  49 +                                           2 /* heartbeat length */ +
  50 +                                           payload + padding;
  51                 int r;
  52
  53 +               if (write_length > SSL3_RT_MAX_PLAIN_LENGTH)
  54 +                       return 0;
  55 +
  56                 /* Allocate memory for the response, size is 1 byte
  57                  * message type, plus 2 bytes payload length, plus
  58                  * payload, plus padding
  59                  */
  60 -               buffer = OPENSSL_malloc(1 + 2 + payload + padding);
  61 +               buffer = OPENSSL_malloc(write_length);
  62                 bp = buffer;
  63
  64                 /* Enter response type, length and copy payload */
  65 @@ -1489,11 +1499,11 @@ dtls1_process_heartbeat(SSL *s)
  66                 /* Random padding */
  67                 RAND_pseudo_bytes(bp, padding);
  68
  69 -               r = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, 3 + payload + padding);
  70 +               r = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, write_length);
  71
  72                 if (r >= 0 && s->msg_callback)
  73                         s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
  74 -                               buffer, 3 + payload + padding,
  75 +                               buffer, write_length,
  76                                 s, s->msg_callback_arg);
  77
  78                 OPENSSL_free(buffer);
  79 diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
  80 index b82fada..bddffd9 100644
  81 --- a/ssl/t1_lib.c
  82 +++ b/ssl/t1_lib.c
  83 @@ -2588,16 +2588,20 @@ tls1_process_heartbeat(SSL *s)
  84         unsigned int payload;
  85         unsigned int padding = 16; /* Use minimum padding */
  86
  87 -       /* Read type and payload length first */
  88 -       hbtype = *p++;
  89 -       n2s(p, payload);
  90 -       pl = p;
  91 -
  92         if (s->msg_callback)
  93                 s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT,
  94                         &s->s3->rrec.data[0], s->s3->rrec.length,
  95                         s, s->msg_callback_arg);
  96
  97 +       /* Read type and payload length first */
  98 +       if (1 + 2 + 16 > s->s3->rrec.length)
  99 +               return 0; /* silently discard */
 100 +       hbtype = *p++;
 101 +       n2s(p, payload);
 102 +       if (1 + 2 + payload + 16 > s->s3->rrec.length)
 103 +               return 0; /* silently discard per RFC 6520 sec. 4 */
 104 +       pl = p;
 105 +
 106         if (hbtype == TLS1_HB_REQUEST)
 107                 {
 108                 unsigned char *buffer, *bp;