diff options
| author | Guy Harris <guy@alum.mit.edu> | 2002-02-23 02:30:16 +0000 |
|---|---|---|
| committer | Guy Harris <guy@alum.mit.edu> | 2002-02-23 02:30:16 +0000 |
| commit | 7027650b5ce8aeeb4e2e7aa91d670d213cde18b2 (patch) | |
| tree | 76c316fccc8cd65e62d297bdd5570830d467c847 /packet-q931.c | |
| parent | 5d5d507a2977fc97c595e4d25a480889001ef615 (diff) | |
"is_tpkt()" is always used to check a TCP segment to see if it might
have a TPKT header at the beginning, so there's not need for it to have
an offset as an argument; its callers don't have to know how big the
TPKT header is (or we can put a #define in "packet-tpkt.h" for it). Get
rid of the second argument.
svn path=/trunk/; revision=4791
Diffstat (limited to 'packet-q931.c')
| -rw-r--r-- | packet-q931.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/packet-q931.c b/packet-q931.c index dcd66b16f2..fe122e9381 100644 --- a/packet-q931.c +++ b/packet-q931.c @@ -2,7 +2,7 @@ * Routines for Q.931 frame disassembly * Guy Harris <guy@alum.mit.edu> * - * $Id: packet-q931.c,v 1.38 2002/02/22 08:56:45 guy Exp $ + * $Id: packet-q931.c,v 1.39 2002/02/23 02:30:15 guy Exp $ * * Modified by Andreas Sikkema for possible use with H.323 * @@ -2498,16 +2498,13 @@ dissect_q931_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, static gboolean dissect_q931_tpkt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { - int offset = 0; - int q931_offset; int lv_tpkt_len; /* * Check whether this looks like a TPKT-encapsulated * Q.931 packet. */ - q931_offset = offset; - lv_tpkt_len = is_tpkt(tvb, &q931_offset); + lv_tpkt_len = is_tpkt(tvb); if (lv_tpkt_len == -1) { /* * It's not a TPKT packet; reject it. @@ -2516,6 +2513,19 @@ dissect_q931_tpkt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) } /* + * If this segment is *exactly* the length of a TPKT header, + * we assume that, as it looks like a TPKT header, it + * is one, and that the code put a TPKT header in one + * segment and the rest of the PDU in another. + */ + if (tvb_length(tvb) == 4) + return TRUE; + + /* + * Well, we have more data than just the TPKT header; + * check whether it looks like the beginning of a + * Q.931 message. + * * The minimum length of a Q.931 message is 3: * 1 byte for the protocol discriminator, * 1 for the call_reference length, @@ -2524,7 +2534,7 @@ dissect_q931_tpkt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) * Check that we have that many bytes past the * TPKT header. */ - if (!tvb_bytes_exist(tvb, q931_offset, 3)) + if (!tvb_bytes_exist(tvb, 4, 3)) return FALSE; /* @@ -2535,7 +2545,7 @@ dissect_q931_tpkt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) return FALSE; /* Check the protocol discriminator */ - if (tvb_get_guint8(tvb, q931_offset) != NLPID_Q_931) { + if (tvb_get_guint8(tvb, 4) != NLPID_Q_931) { /* Doesn't look like Q.931 inside TPKT */ return FALSE; } |