code.ossystems Code Review - openembedded-core.git/blob

   1 From 34628967f1e65dc8f34e000f0f5518e21afbfc7b Mon Sep 17 00:00:00 2001
   2 From: "Dr. Stephen Henson" <steve@openssl.org>
   3 Date: Fri, 20 Dec 2013 15:26:50 +0000
   4 Subject: [PATCH] Fix DTLS retransmission from previous session.
   5
   6 Upstream-Status: Backport
   7 commit 34628967f1e65dc8f34e000f0f5518e21afbfc7b upstream
   8
   9 For DTLS we might need to retransmit messages from the previous session
  10 so keep a copy of write context in DTLS retransmission buffers instead
  11 of replacing it after sending CCS. CVE-2013-6450.
  12 ---
  13  ssl/d1_both.c  |    6 ++++++
  14  ssl/ssl_locl.h |    2 ++
  15  ssl/t1_enc.c   |   17 +++++++++++------
  16  4 files changed, 24 insertions(+), 6 deletions(-)
  17
  18 diff --git a/ssl/d1_both.c b/ssl/d1_both.c
  19 index 65ec001..7a5596a 100644
  20 --- a/ssl/d1_both.c
  21 +++ b/ssl/d1_both.c
  22 @@ -214,6 +214,12 @@ dtls1_hm_fragment_new(unsigned long frag_len, int reassembly)
  23  static void
  24  dtls1_hm_fragment_free(hm_fragment *frag)
  25         {
  26 +
  27 +       if (frag->msg_header.is_ccs)
  28 +               {
  29 +               EVP_CIPHER_CTX_free(frag->msg_header.saved_retransmit_state.enc_write_ctx);
  30 +               EVP_MD_CTX_destroy(frag->msg_header.saved_retransmit_state.write_hash);
  31 +               }
  32         if (frag->fragment) OPENSSL_free(frag->fragment);
  33         if (frag->reassembly) OPENSSL_free(frag->reassembly);
  34         OPENSSL_free(frag);
  35 diff --git a/ssl/ssl_locl.h b/ssl/ssl_locl.h
  36 index 96ce9a7..e485907 100644
  37 --- a/ssl/ssl_locl.h
  38 +++ b/ssl/ssl_locl.h
  39 @@ -621,6 +621,8 @@ extern SSL3_ENC_METHOD TLSv1_enc_data;
  40  extern SSL3_ENC_METHOD SSLv3_enc_data;
  41  extern SSL3_ENC_METHOD DTLSv1_enc_data;
  42
  43 +#define SSL_IS_DTLS(s) (s->method->version == DTLS1_VERSION)
  44 +
  45  #define IMPLEMENT_tls_meth_func(version, func_name, s_accept, s_connect, \
  46                                 s_get_meth) \
  47  const SSL_METHOD *func_name(void)  \
  48 diff --git a/ssl/t1_enc.c b/ssl/t1_enc.c
  49 index 72015f5..56db834 100644
  50 --- a/ssl/t1_enc.c
  51 +++ b/ssl/t1_enc.c
  52 @@ -414,15 +414,20 @@ int tls1_change_cipher_state(SSL *s, int which)
  53                         s->mac_flags |= SSL_MAC_FLAG_WRITE_MAC_STREAM;
  54                         else
  55                         s->mac_flags &= ~SSL_MAC_FLAG_WRITE_MAC_STREAM;
  56 -               if (s->enc_write_ctx != NULL)
  57 +               if (s->enc_write_ctx != NULL && !SSL_IS_DTLS(s))
  58                         reuse_dd = 1;
  59 -               else if ((s->enc_write_ctx=OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL)
  60 +               else if ((s->enc_write_ctx=EVP_CIPHER_CTX_new()) == NULL)
  61                         goto err;
  62 -               else
  63 -                       /* make sure it's intialized in case we exit later with an error */
  64 -                       EVP_CIPHER_CTX_init(s->enc_write_ctx);
  65                 dd= s->enc_write_ctx;
  66 -               mac_ctx = ssl_replace_hash(&s->write_hash,NULL);
  67 +               if (SSL_IS_DTLS(s))
  68 +                       {
  69 +                       mac_ctx = EVP_MD_CTX_create();
  70 +                       if (!mac_ctx)
  71 +                               goto err;
  72 +                       s->write_hash = mac_ctx;
  73 +                       }
  74 +               else
  75 +                       mac_ctx = ssl_replace_hash(&s->write_hash,NULL);
  76  #ifndef OPENSSL_NO_COMP
  77                 if (s->compress != NULL)
  78                         {
  79 --
  80 1.7.5.4
  81