As UCP is atop TCP, its dissector isn't called unless there's at least

one byte in the tvbuff being handed to it, so the check I added for the
existence of that byte is unnecessary.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@4011 f5534014-38df-0310-8fa8-9805f1628bb7

diff --git a/packet-ucp.c b/packet-ucp.c
index d99f6a161c5fb7ebf8b0ce20b5132952bfb0cef1..6a841fbd298515b97deb6b3b962b5901a58886ec 100644 (file)
--- a/packet-ucp.c
+++ b/packet-ucp.c
@@ -2,7 +2,7 @@
  * Routines for Universal Computer Protocol dissection
  * Copyright 2001, Tom Uijldert <tom.uijldert@cmg.nl>
  *
- * $Id: packet-ucp.c,v 1.2 2001/10/08 17:37:52 guy Exp $
+ * $Id: packet-ucp.c,v 1.3 2001/10/08 17:42:18 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -625,10 +625,6 @@ static const value_string vals_xser_service[] = {
  * \retval     UCP_SHORTENED   Packet may be there, but not complete
  * \retval     UCP_MALFORMED   Hmmmm, not UCP after all...
  * \retval     UCP_INV_CHK     Nice packet, but checksum doesn't add up...
- *
- * Note that this will not recognize any frames as UCP frames if the
- * capture was made with a snapshot length shorter than the maximum
- * frame length, as it checksums the entire packet.
  */
 static int
 check_ucp(tvbuff_t *tvb, int *endpkt)
@@ -638,9 +634,6 @@ check_ucp(tvbuff_t *tvb, int *endpkt)
     int                 pkt_check, tmp;
     int                 length;
 
-    if (!tvb_offset_exists(tvb, 0) || tvb_get_guint8(tvb, 0) != UCP_STX)
-       return UCP_MALFORMED;
-
     length = tvb_find_guint8(tvb, offset, -1, UCP_ETX);
     if (length == -1) {
        *endpkt = tvb_reported_length_remaining(tvb, offset);
@@ -1542,6 +1535,11 @@ dissect_ucp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     proto_tree *ucp_tree;
     tvbuff_t   *tmp_tvb;
 
+    /* This runs atop TCP, so we are guaranteed that there is at least one
+       byte in the tvbuff. */
+    if (tvb_get_guint8(tvb, 0) != UCP_STX)
+       return FALSE;
+
     result = check_ucp(tvb, &endpkt);
 
     if (result == UCP_MALFORMED)