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