svn commit: r218634 - stable/7/crypto/openssl/ssl

[Simon L. Nielsen]

Author: simon
Date: Sun Feb 13 10:24:36 2011
New Revision: 218634
URL: http://svn.freebsd.org/changeset/base/218634

Log:
  MFC 218625:
   Fix Incorrectly formatted ClientHello SSL/TLS handshake messages could
   cause OpenSSL to parse past the end of the message.
  
   Note: Applications are only affected if they act as a server and call
   SSL_CTX_set_tlsext_status_cb on the server's SSL_CTX. This includes
   Apache httpd >= 2.3.3, if configured with "SSLUseStapling On".
  
  The very quick MFC is done to get this fix into 7.4 / 8.2.
  
  Discussed with:	re
  Approved by:	so (simon, for "instant" MFC)
  Obtained from:	OpenSSL CVS
  Security:	http://www.openssl.org/news/secadv_20110208.txt
  Security:	CVE-2011-0014

Modified:
  stable/7/crypto/openssl/ssl/t1_lib.c
Directory Properties:
  stable/7/crypto/openssl/   (props changed)

Modified: stable/7/crypto/openssl/ssl/t1_lib.c
==============================================================================
--- stable/7/crypto/openssl/ssl/t1_lib.c	Sun Feb 13 10:22:43 2011	(r218633)
+++ stable/7/crypto/openssl/ssl/t1_lib.c	Sun Feb 13 10:24:36 2011	(r218634)
@@ -521,6 +521,7 @@ int ssl_parse_clienthello_tlsext(SSL *s,
 						}
 					n2s(data, idsize);
 					dsize -= 2 + idsize;
+					size -= 2 + idsize;
 					if (dsize < 0)
 						{
 						*al = SSL_AD_DECODE_ERROR;
@@ -559,9 +560,14 @@ int ssl_parse_clienthello_tlsext(SSL *s,
 					}
 
 				/* Read in request_extensions */
+				if (size < 2)
+					{
+					*al = SSL_AD_DECODE_ERROR;
+					return 0;
+					}
 				n2s(data,dsize);
 				size -= 2;
-				if (dsize > size) 
+				if (dsize != size)
 					{
 					*al = SSL_AD_DECODE_ERROR;
 					return 0;