Fix bug in CVE-2011-4619: check we have really received a client hello

before rejecting multiple SGC restarts.

diff --git a/CHANGES b/CHANGES
index 08449ffd14a9a0bf5e1efbf0e6ad62c25d9f2ad0..0ee54e3f2f227e997f92be1dffe71f9e9a257fdd 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -4,7 +4,10 @@
 
  Changes between 1.0.0g and 1.0.0h [xx XXX xxxx]
 
-  *)
+  *) Fix CVE-2011-4619: make sure we really are receiving a 
+     client hello before rejecting multiple SGC restarts. Thanks to
+     Ivan Nestlerode <inestlerode@us.ibm.com> for discovering this bug.
+     [Steve Henson]
 
  Changes between 1.0.0f and 1.0.0g [18 Jan 2012]
 

diff --git a/ssl/s3_srvr.c b/ssl/s3_srvr.c
index d734c359fb2a978d967e592b512bf45748a11359..a79c986da3ee7a4df1af4a8a868a27ea81247157 100644 (file)
--- a/ssl/s3_srvr.c
+++ b/ssl/s3_srvr.c
@@ -756,14 +756,6 @@ int ssl3_check_client_hello(SSL *s)
        int ok;
        long n;
 
-       /* We only allow the client to restart the handshake once per
-        * negotiation. */
-       if (s->s3->flags & SSL3_FLAGS_SGC_RESTART_DONE)
-               {
-               SSLerr(SSL_F_SSL3_CHECK_CLIENT_HELLO, SSL_R_MULTIPLE_SGC_RESTARTS);
-               return -1;
-               }
-
        /* this function is called when we really expect a Certificate message,
         * so permit appropriate message length */
        n=s->method->ssl_get_message(s,
@@ -776,6 +768,13 @@ int ssl3_check_client_hello(SSL *s)
        s->s3->tmp.reuse_message = 1;
        if (s->s3->tmp.message_type == SSL3_MT_CLIENT_HELLO)
                {
+               /* We only allow the client to restart the handshake once per
+                * negotiation. */
+               if (s->s3->flags & SSL3_FLAGS_SGC_RESTART_DONE)
+                       {
+                       SSLerr(SSL_F_SSL3_CHECK_CLIENT_HELLO, SSL_R_MULTIPLE_SGC_RESTARTS);
+                       return -1;
+                       }
                /* Throw away what we have done so far in the current handshake,
                 * which will now be aborted. (A full SSL_clear would be too much.) */
 #ifndef OPENSSL_NO_DH