Attachment 924724 Details for Bug 1127504 – CVE-2014-3511 patch

[patch] CVE-2014-3511 patch

file_1127504.txt (text/plain), 2.10 KB, created by Loganaden Velvindron on 2014-08-07 07:13:40 UTC

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Creator: Loganaden Velvindron

Created: 2014-08-07 07:13:40 UTC

Size: 2.10 KB

patch

obsolete

>--- openssl-1.0.1e/ssl/s23_srvr.c.orig	2013-02-11 19:26:04.000000000 +0400
>+++ openssl-1.0.1e/ssl/s23_srvr.c	2014-08-07 11:08:32.747362924 +0400
>@@ -348,23 +348,19 @@ int ssl23_get_client_hello(SSL *s)
> 			 * Client Hello message, this would be difficult, and we'd have
> 			 * to read more records to find out.
> 			 * No known SSL 3.0 client fragments ClientHello like this,
>-			 * so we simply assume TLS 1.0 to avoid protocol version downgrade
>-			 * attacks. */
>+			 * so we simply reject such connections to avoid
>+			 * protocol version downgrade attacks. */
> 			if (p[3] == 0 && p[4] < 6)
> 				{
>-#if 0
> 				SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_SMALL);
> 				goto err;
>-#else
>-				v[1] = TLS1_VERSION_MINOR;
>-#endif
> 				}
> 			/* if major version number > 3 set minor to a value
> 			 * which will use the highest version 3 we support.
> 			 * If TLS 2.0 ever appears we will need to revise
> 			 * this....
> 			 */
>-			else if (p[9] > SSL3_VERSION_MAJOR)
>+			if (p[9] > SSL3_VERSION_MAJOR)
> 				v[1]=0xff;
> 			else
> 				v[1]=p[10]; /* minor version according to client_version */
>@@ -444,14 +440,34 @@ int ssl23_get_client_hello(SSL *s)
> 		v[0] = p[3]; /* == SSL3_VERSION_MAJOR */
> 		v[1] = p[4];
> 
>+		/* An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
>+		 * header is sent directly on the wire, not wrapped as a TLS
>+		 * record. It's format is:
>+		 * Byte  Content
>+		 * 0-1   msg_length
>+		 * 2     msg_type
>+		 * 3-4   version
>+		 * 5-6   cipher_spec_length
>+		 * 7-8   session_id_length
>+		 * 9-10  challenge_length
>+		 * ...   ...
>+		 */
> 		n=((p[0]&0x7f)<<8)|p[1];
> 		if (n > (1024*4))
> 			{
> 			SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_LARGE);
> 			goto err;
> 			}
>+		if (n < 9)
>+			{
>+			SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH);
>+			goto err;
>+			}
> 
> 		j=ssl23_read_bytes(s,n+2);
>+		/* We previously read 11 bytes, so if j > 0, we must have
>+		 * j == n+2 == s->packet_length. We have at least 11 valid
>+		 * packet bytes. */
> 		if (j <= 0) return(j);
> 
> 		ssl3_finish_mac(s, s->packet+2, s->packet_length-2);

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Attachments on bug 1127504: 924724