Workaround for irrelevant problem.

[openssl.git] / ssl / s23_srvr.c

diff --git a/ssl/s23_srvr.c b/ssl/s23_srvr.c
index 49320647e7033e93ec4da90f34f6a91866c4307f..33634efdcb3537e9187ddde05af80563d70e5a7a 100644 (file)
--- a/ssl/s23_srvr.c
+++ b/ssl/s23_srvr.c
@@ -189,9 +189,10 @@ end:
 int ssl23_get_client_hello(SSL *s)
        {
        char buf_space[11]; /* Request this many bytes in initial read.
-                            * We can detect SSL 3.0/TLS 1.0 Client Hellos only
-                            * when the following is in a single record
-                            * (not guaranteed by protocol specs):
+                            * We can detect SSL 3.0/TLS 1.0 Client Hellos
+                            * ('type == 3') correctly only when the following
+                            * is in a single record, which is not guaranteed by
+                            * the protocol specification:
                             * Byte  Content
                             *  0     type            \
                             *  1/2   version          > record header
@@ -200,7 +201,6 @@ int ssl23_get_client_hello(SSL *s)
                             *  6-8   length           > Client Hello message
                             *  9/10  client_version  /
                             */
-/* XXX */
        char *buf= &(buf_space[0]);
        unsigned char *p,*d,*dd;
        unsigned int i;
@@ -338,14 +338,23 @@ int ssl23_get_client_hello(SSL *s)
                else if ((p[0] == SSL3_RT_HANDSHAKE) &&
                         (p[1] == SSL3_VERSION_MAJOR) &&
                         (p[5] == SSL3_MT_CLIENT_HELLO) &&
-                        (p[9] == p[1]))
+                        ((p[3] == 0 && p[4] < 5 /* silly record length? */)
+                               || (p[9] == p[1])))
                        {
                        /*
                         * SSLv3 or tls1 header
                         */
                        
-                       /* we must look at client_version inside the client hello: */
-                       v[0]=p[9]; v[1]=p[10];
+                       v[0]=p[1]; /* major version */
+                       /* We must look at client_version inside the Client Hello message
+                        * to get the correct minor version: */
+                       v[1]=p[10];
+                       /* However if we have only a pathologically small fragment of the
+                        * Client Hello message, we simply use the version from the
+                        * record header -- this is incorrect but unlikely to fail in
+                        * practice */
+                       if (p[3] == 0 && p[4] < 6)
+                               v[1]=p[2];
                        if (v[1] >= TLS1_VERSION_MINOR)
                                {
                                if (!(s->options & SSL_OP_NO_TLSv1))