diff options
| author | Dr. Stephen Henson <steve@openssl.org> | 2013-12-20 15:26:50 +0000 |
|---|---|---|
| committer | Dr. Stephen Henson <steve@openssl.org> | 2013-12-20 23:12:18 +0000 |
| commit | 34628967f1e65dc8f34e000f0f5518e21afbfc7b (patch) | |
| tree | c7a2fa589782c89a05845733b12df9d437140689 /ssl | |
| parent | a6c62f0c25a756c263a80ce52afbae888028e986 (diff) | |
Fix DTLS retransmission from previous session.
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.
Diffstat (limited to 'ssl')
| -rw-r--r-- | ssl/d1_both.c | 6 | ||||
| -rw-r--r-- | ssl/ssl_locl.h | 2 | ||||
| -rw-r--r-- | ssl/t1_enc.c | 17 |
3 files changed, 19 insertions, 6 deletions
diff --git a/ssl/d1_both.c b/ssl/d1_both.c index 65ec0018ae..7a5596a6b3 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 96ce9a7245..e485907748 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 72015f5aad..56db834306 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) { |