forked from osmocom/wireshark
79e1fdb9e5
statements. Move the setting of the Protocol column in the Appletalk ARP and IPX dissectors before anything is fetched from the packet, and also clear the Info column at that point in those and some other dissectors, so that if an exception is thrown, the columns don't reflect the previous protocol. Fix the registration of the IPX RIP dissector to use the right protocol ID. svn path=/trunk/; revision=2928
145 lines
4 KiB
C
145 lines
4 KiB
C
/* packet-lapb.c
|
|
* Routines for lapb frame disassembly
|
|
* Olivier Abad <oabad@cybercable.fr>
|
|
*
|
|
* $Id: packet-lapb.c,v 1.28 2001/01/22 00:20:29 guy Exp $
|
|
*
|
|
* Ethereal - Network traffic analyzer
|
|
* By Gerald Combs <gerald@zing.org>
|
|
* Copyright 1998
|
|
*
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
# include "config.h"
|
|
#endif
|
|
|
|
#ifdef HAVE_SYS_TYPES_H
|
|
# include <sys/types.h>
|
|
#endif
|
|
|
|
#include <stdio.h>
|
|
#include <glib.h>
|
|
#include <string.h>
|
|
#include "packet.h"
|
|
#include "packet-x25.h"
|
|
#include "xdlc.h"
|
|
|
|
#define FROM_DCE 0x80
|
|
|
|
static int proto_lapb = -1;
|
|
static int hf_lapb_address = -1;
|
|
static int hf_lapb_control = -1;
|
|
|
|
static gint ett_lapb = -1;
|
|
static gint ett_lapb_control = -1;
|
|
|
|
static void
|
|
dissect_lapb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
proto_tree *lapb_tree, *ti;
|
|
int is_response;
|
|
guint8 byte0;
|
|
tvbuff_t *next_tvb;
|
|
|
|
if (check_col(pinfo->fd, COL_PROTOCOL))
|
|
col_set_str(pinfo->fd, COL_PROTOCOL, "LAPB");
|
|
if (check_col(pinfo->fd, COL_INFO))
|
|
col_clear(pinfo->fd, COL_INFO);
|
|
|
|
if (pinfo->pseudo_header->x25.flags & FROM_DCE) {
|
|
if(check_col(pinfo->fd, COL_RES_DL_DST))
|
|
col_set_str(pinfo->fd, COL_RES_DL_DST, "DTE");
|
|
if(check_col(pinfo->fd, COL_RES_DL_SRC))
|
|
col_set_str(pinfo->fd, COL_RES_DL_SRC, "DCE");
|
|
}
|
|
else {
|
|
if(check_col(pinfo->fd, COL_RES_DL_DST))
|
|
col_set_str(pinfo->fd, COL_RES_DL_DST, "DCE");
|
|
if(check_col(pinfo->fd, COL_RES_DL_SRC))
|
|
col_set_str(pinfo->fd, COL_RES_DL_SRC, "DTE");
|
|
}
|
|
|
|
byte0 = tvb_get_guint8(tvb, 0);
|
|
|
|
if (byte0 != 0x01 && byte0 != 0x03) /* invalid LAPB frame */
|
|
{
|
|
if (check_col(pinfo->fd, COL_INFO))
|
|
col_set_str(pinfo->fd, COL_INFO, "Invalid LAPB frame");
|
|
if (tree)
|
|
ti = proto_tree_add_protocol_format(tree, proto_lapb, tvb, 0,
|
|
tvb_length(tvb), "Invalid LAPB frame");
|
|
return;
|
|
}
|
|
|
|
if (((pinfo->pseudo_header->x25.flags & FROM_DCE) && byte0 == 0x01) ||
|
|
(!(pinfo->pseudo_header->x25.flags & FROM_DCE) && byte0 == 0x03))
|
|
is_response = TRUE;
|
|
else
|
|
is_response = FALSE;
|
|
|
|
if (tree) {
|
|
ti = proto_tree_add_protocol_format(tree, proto_lapb, tvb, 0, 2,
|
|
"LAPB");
|
|
lapb_tree = proto_item_add_subtree(ti, ett_lapb);
|
|
proto_tree_add_uint_format(lapb_tree, hf_lapb_address, tvb, 0, 1, byte0,
|
|
"Address: 0x%02X", byte0);
|
|
}
|
|
else
|
|
lapb_tree = NULL;
|
|
|
|
dissect_xdlc_control(tvb, 1, pinfo, lapb_tree, hf_lapb_control,
|
|
ett_lapb_control, is_response, FALSE);
|
|
|
|
/* not end of frame ==> X.25 */
|
|
if (tvb_length(tvb) > 2) {
|
|
next_tvb = tvb_new_subset(tvb, 2, -1, -1);
|
|
dissect_x25(next_tvb, pinfo, tree);
|
|
}
|
|
}
|
|
|
|
void
|
|
proto_register_lapb(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
{ &hf_lapb_address,
|
|
{ "Address Field", "lapb.address", FT_UINT8, BASE_HEX, NULL, 0x0,
|
|
"Address" }},
|
|
|
|
{ &hf_lapb_control,
|
|
{ "Control Field", "lapb.control", FT_UINT8, BASE_HEX, NULL, 0x0,
|
|
"Control field" }},
|
|
};
|
|
static gint *ett[] = {
|
|
&ett_lapb,
|
|
&ett_lapb_control,
|
|
};
|
|
|
|
proto_lapb = proto_register_protocol("Link Access Procedure Balanced (LAPB)",
|
|
"LAPB", "lapb");
|
|
proto_register_field_array (proto_lapb, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
|
|
register_dissector("lapb", dissect_lapb, proto_lapb);
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_lapb(void)
|
|
{
|
|
dissector_add("wtap_encap", WTAP_ENCAP_LAPB, dissect_lapb, proto_lapb);
|
|
}
|