![Anders Broman](/assets/img/avatar_default.png)
Fix some C++ comments in C source files and fixes some non-constant initializations. svn path=/trunk/; revision=18521
342 lines
9.9 KiB
C
342 lines
9.9 KiB
C
/* packet-lapd.c
|
|
* Routines for LAPD frame disassembly
|
|
* Gilbert Ramirez <gram@alumni.rice.edu>
|
|
*
|
|
* $Id$
|
|
*
|
|
* Wireshark - Network traffic analyzer
|
|
* By Gerald Combs <gerald@wireshark.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
|
|
|
|
#include <stdio.h>
|
|
#include <glib.h>
|
|
#include <string.h>
|
|
#include <epan/packet.h>
|
|
#include <epan/xdlc.h>
|
|
|
|
#include <epan/lapd_sapi.h>
|
|
|
|
/* ISDN/LAPD references:
|
|
*
|
|
* http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/isdn.htm
|
|
* http://www.ece.wpi.edu/courses/ee535/hwk11cd95/agrebe/agrebe.html
|
|
* http://www.acacia-net.com/Clarinet/Protocol/q9213o84.htm
|
|
*/
|
|
|
|
static int proto_lapd = -1;
|
|
static int hf_lapd_address = -1;
|
|
static int hf_lapd_sapi = -1;
|
|
static int hf_lapd_cr = -1;
|
|
static int hf_lapd_ea1 = -1;
|
|
static int hf_lapd_tei = -1;
|
|
static int hf_lapd_ea2 = -1;
|
|
static int hf_lapd_control = -1;
|
|
static int hf_lapd_n_r = -1;
|
|
static int hf_lapd_n_s = -1;
|
|
static int hf_lapd_p = -1;
|
|
static int hf_lapd_p_ext = -1;
|
|
static int hf_lapd_f = -1;
|
|
static int hf_lapd_f_ext = -1;
|
|
static int hf_lapd_s_ftype = -1;
|
|
static int hf_lapd_u_modifier_cmd = -1;
|
|
static int hf_lapd_u_modifier_resp = -1;
|
|
static int hf_lapd_ftype_i = -1;
|
|
static int hf_lapd_ftype_s_u = -1;
|
|
static int hf_lapd_ftype_s_u_ext = -1;
|
|
|
|
static gint ett_lapd = -1;
|
|
static gint ett_lapd_address = -1;
|
|
static gint ett_lapd_control = -1;
|
|
|
|
static dissector_table_t lapd_sapi_dissector_table;
|
|
|
|
static dissector_handle_t data_handle;
|
|
static dissector_handle_t tei_handle;
|
|
|
|
/*
|
|
* Bits in the address field.
|
|
*/
|
|
#define LAPD_SAPI 0xfc00 /* Service Access Point Identifier */
|
|
#define LAPD_SAPI_SHIFT 10
|
|
#define LAPD_CR 0x0200 /* Command/Response bit */
|
|
#define LAPD_EA1 0x0100 /* First Address Extension bit */
|
|
#define LAPD_TEI 0x00fe /* Terminal Endpoint Identifier */
|
|
#define LAPD_TEI_SHIFT 1
|
|
#define LAPD_EA2 0x0001 /* Second Address Extension bit */
|
|
|
|
static const value_string lapd_sapi_vals[] = {
|
|
{ LAPD_SAPI_Q931, "Q.931 Call control procedure" },
|
|
{ LAPD_SAPI_PM_Q931, "Packet mode Q.931 Call control procedure" },
|
|
{ LAPD_SAPI_X25, "X.25 Level 3 procedures" },
|
|
{ LAPD_SAPI_L2, "Layer 2 management procedures" },
|
|
{ 0, NULL }
|
|
};
|
|
|
|
/* Used only for U frames */
|
|
static const xdlc_cf_items lapd_cf_items = {
|
|
NULL,
|
|
NULL,
|
|
&hf_lapd_p,
|
|
&hf_lapd_f,
|
|
NULL,
|
|
&hf_lapd_u_modifier_cmd,
|
|
&hf_lapd_u_modifier_resp,
|
|
NULL,
|
|
&hf_lapd_ftype_s_u
|
|
};
|
|
|
|
/* Used only for I and S frames */
|
|
static const xdlc_cf_items lapd_cf_items_ext = {
|
|
&hf_lapd_n_r,
|
|
&hf_lapd_n_s,
|
|
&hf_lapd_p_ext,
|
|
&hf_lapd_f_ext,
|
|
&hf_lapd_s_ftype,
|
|
NULL,
|
|
NULL,
|
|
&hf_lapd_ftype_i,
|
|
&hf_lapd_ftype_s_u_ext
|
|
};
|
|
|
|
static void
|
|
dissect_lapd(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
|
{
|
|
proto_tree *lapd_tree, *addr_tree;
|
|
proto_item *lapd_ti, *addr_ti;
|
|
guint16 control;
|
|
int lapd_header_len;
|
|
guint16 address, cr, sapi, tei;
|
|
gboolean is_response = 0;
|
|
tvbuff_t *next_tvb;
|
|
char *srcname = "?";
|
|
char *dstname = "?";
|
|
|
|
if (check_col(pinfo->cinfo, COL_PROTOCOL))
|
|
col_set_str(pinfo->cinfo, COL_PROTOCOL, "LAPD");
|
|
if (check_col(pinfo->cinfo, COL_INFO))
|
|
col_clear(pinfo->cinfo, COL_INFO);
|
|
|
|
address = tvb_get_ntohs(tvb, 0);
|
|
cr = address & LAPD_CR;
|
|
tei = (address & LAPD_TEI) >> LAPD_TEI_SHIFT;
|
|
sapi = (address & LAPD_SAPI) >> LAPD_SAPI_SHIFT;
|
|
lapd_header_len = 2; /* address */
|
|
|
|
if (check_col(pinfo->cinfo, COL_TEI))
|
|
col_add_fstr(pinfo->cinfo, COL_TEI, "%u", tei);
|
|
|
|
if (pinfo->fd->lnk_t == WTAP_ENCAP_LINUX_LAPD) {
|
|
/* frame is captured via libpcap */
|
|
if (pinfo->pseudo_header->lapd.pkttype == 4 /*PACKET_OUTGOING*/) {
|
|
if (pinfo->pseudo_header->lapd.we_network) {
|
|
is_response = cr ? FALSE : TRUE;
|
|
srcname = "Local Network";
|
|
dstname = "Remote User";
|
|
} else {
|
|
srcname = "Local User";
|
|
dstname = "Remote Network";
|
|
}
|
|
}
|
|
else if (pinfo->pseudo_header->lapd.pkttype == 3 /*PACKET_OTHERHOST*/) {
|
|
/* We must be a TE, sniffing what other TE transmit */
|
|
|
|
is_response = cr ? TRUE : FALSE;
|
|
srcname = "Remote User";
|
|
dstname = "Remote Network";
|
|
}
|
|
else {
|
|
/* The frame is incoming */
|
|
if (pinfo->pseudo_header->lapd.we_network) {
|
|
is_response = cr ? TRUE : FALSE;
|
|
srcname = "Remote User";
|
|
dstname = "Local Network";
|
|
} else {
|
|
is_response = cr ? FALSE : TRUE;
|
|
srcname = "Remote Network";
|
|
dstname = "Local User";
|
|
}
|
|
}
|
|
}
|
|
else if (pinfo->p2p_dir == P2P_DIR_SENT) {
|
|
is_response = cr ? FALSE : TRUE;
|
|
srcname = "Network";
|
|
dstname = "User";
|
|
}
|
|
else if (pinfo->p2p_dir == P2P_DIR_RECV) {
|
|
is_response = cr ? TRUE : FALSE;
|
|
srcname = "User";
|
|
dstname = "Network";
|
|
}
|
|
|
|
if(check_col(pinfo->cinfo, COL_RES_DL_SRC))
|
|
col_set_str(pinfo->cinfo, COL_RES_DL_SRC, srcname);
|
|
if(check_col(pinfo->cinfo, COL_RES_DL_DST))
|
|
col_set_str(pinfo->cinfo, COL_RES_DL_DST, dstname);
|
|
|
|
if (tree) {
|
|
lapd_ti = proto_tree_add_item(tree, proto_lapd, tvb, 0, -1,
|
|
FALSE);
|
|
lapd_tree = proto_item_add_subtree(lapd_ti, ett_lapd);
|
|
|
|
addr_ti = proto_tree_add_uint(lapd_tree, hf_lapd_address, tvb,
|
|
0, 2, address);
|
|
addr_tree = proto_item_add_subtree(addr_ti, ett_lapd_address);
|
|
|
|
proto_tree_add_uint(addr_tree, hf_lapd_sapi,tvb, 0, 1, address);
|
|
proto_tree_add_uint(addr_tree, hf_lapd_cr, tvb, 0, 1, address);
|
|
proto_tree_add_uint(addr_tree, hf_lapd_ea1, tvb, 0, 1, address);
|
|
proto_tree_add_uint(addr_tree, hf_lapd_tei, tvb, 1, 1, address);
|
|
proto_tree_add_uint(addr_tree, hf_lapd_ea2, tvb, 1, 1, address);
|
|
}
|
|
else {
|
|
lapd_ti = NULL;
|
|
lapd_tree = NULL;
|
|
}
|
|
|
|
control = dissect_xdlc_control(tvb, 2, pinfo, lapd_tree, hf_lapd_control,
|
|
ett_lapd_control, &lapd_cf_items, &lapd_cf_items_ext, NULL, NULL,
|
|
is_response, TRUE, FALSE);
|
|
lapd_header_len += XDLC_CONTROL_LEN(control, TRUE);
|
|
|
|
if (tree)
|
|
proto_item_set_len(lapd_ti, lapd_header_len);
|
|
|
|
next_tvb = tvb_new_subset(tvb, lapd_header_len, -1, -1);
|
|
if (XDLC_IS_INFORMATION(control)) {
|
|
/* call next protocol */
|
|
if (!dissector_try_port(lapd_sapi_dissector_table, sapi,
|
|
next_tvb, pinfo, tree))
|
|
call_dissector(data_handle,next_tvb, pinfo, tree);
|
|
} else
|
|
call_dissector(data_handle,next_tvb, pinfo, tree);
|
|
}
|
|
|
|
void
|
|
proto_register_lapd(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
{ &hf_lapd_address,
|
|
{ "Address Field", "lapd.address", FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
"Address", HFILL }},
|
|
|
|
{ &hf_lapd_sapi,
|
|
{ "SAPI", "lapd.sapi", FT_UINT16, BASE_DEC, VALS(lapd_sapi_vals), LAPD_SAPI,
|
|
"Service Access Point Identifier", HFILL }},
|
|
|
|
{ &hf_lapd_cr,
|
|
{ "C/R", "lapd.cr", FT_UINT16, BASE_DEC, NULL, LAPD_CR,
|
|
"Command/Response bit", HFILL }},
|
|
|
|
{ &hf_lapd_ea1,
|
|
{ "EA1", "lapd.ea1", FT_UINT16, BASE_DEC, NULL, LAPD_EA1,
|
|
"First Address Extension bit", HFILL }},
|
|
|
|
{ &hf_lapd_tei,
|
|
{ "TEI", "lapd.tei", FT_UINT16, BASE_DEC, NULL, LAPD_TEI,
|
|
"Terminal Endpoint Identifier", HFILL }},
|
|
|
|
{ &hf_lapd_ea2,
|
|
{ "EA2", "lapd.ea2", FT_UINT16, BASE_DEC, NULL, LAPD_EA2,
|
|
"Second Address Extension bit", HFILL }},
|
|
|
|
{ &hf_lapd_control,
|
|
{ "Control Field", "lapd.control", FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
"Control field", HFILL }},
|
|
|
|
{ &hf_lapd_n_r,
|
|
{ "N(R)", "lapd.control.n_r", FT_UINT16, BASE_DEC,
|
|
NULL, XDLC_N_R_EXT_MASK, "", HFILL }},
|
|
|
|
{ &hf_lapd_n_s,
|
|
{ "N(S)", "lapd.control.n_s", FT_UINT16, BASE_DEC,
|
|
NULL, XDLC_N_S_EXT_MASK, "", HFILL }},
|
|
|
|
{ &hf_lapd_p,
|
|
{ "Poll", "lapd.control.p", FT_BOOLEAN, 8,
|
|
TFS(&flags_set_truth), XDLC_P_F, "", HFILL }},
|
|
|
|
{ &hf_lapd_p_ext,
|
|
{ "Poll", "lapd.control.p", FT_BOOLEAN, 16,
|
|
TFS(&flags_set_truth), XDLC_P_F_EXT, "", HFILL }},
|
|
|
|
{ &hf_lapd_f,
|
|
{ "Final", "lapd.control.f", FT_BOOLEAN, 8,
|
|
TFS(&flags_set_truth), XDLC_P_F, "", HFILL }},
|
|
|
|
{ &hf_lapd_f_ext,
|
|
{ "Final", "lapd.control.f", FT_BOOLEAN, 16,
|
|
TFS(&flags_set_truth), XDLC_P_F_EXT, "", HFILL }},
|
|
|
|
{ &hf_lapd_s_ftype,
|
|
{ "Supervisory frame type", "lapd.control.s_ftype", FT_UINT16, BASE_HEX,
|
|
VALS(stype_vals), XDLC_S_FTYPE_MASK, "", HFILL }},
|
|
|
|
{ &hf_lapd_u_modifier_cmd,
|
|
{ "Command", "lapd.control.u_modifier_cmd", FT_UINT8, BASE_HEX,
|
|
VALS(modifier_vals_cmd), XDLC_U_MODIFIER_MASK, "", HFILL }},
|
|
|
|
{ &hf_lapd_u_modifier_resp,
|
|
{ "Response", "lapd.control.u_modifier_resp", FT_UINT8, BASE_HEX,
|
|
VALS(modifier_vals_resp), XDLC_U_MODIFIER_MASK, "", HFILL }},
|
|
|
|
{ &hf_lapd_ftype_i,
|
|
{ "Frame type", "lapd.control.ftype", FT_UINT16, BASE_HEX,
|
|
VALS(ftype_vals), XDLC_I_MASK, "", HFILL }},
|
|
|
|
{ &hf_lapd_ftype_s_u,
|
|
{ "Frame type", "lapd.control.ftype", FT_UINT8, BASE_HEX,
|
|
VALS(ftype_vals), XDLC_S_U_MASK, "", HFILL }},
|
|
|
|
{ &hf_lapd_ftype_s_u_ext,
|
|
{ "Frame type", "lapd.control.ftype", FT_UINT16, BASE_HEX,
|
|
VALS(ftype_vals), XDLC_S_U_MASK, "", HFILL }},
|
|
};
|
|
static gint *ett[] = {
|
|
&ett_lapd,
|
|
&ett_lapd_address,
|
|
&ett_lapd_control,
|
|
};
|
|
|
|
proto_lapd = proto_register_protocol("Link Access Procedure, Channel D (LAPD)",
|
|
"LAPD", "lapd");
|
|
proto_register_field_array (proto_lapd, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
|
|
register_dissector("lapd", dissect_lapd, proto_lapd);
|
|
|
|
lapd_sapi_dissector_table = register_dissector_table("lapd.sapi",
|
|
"LAPD SAPI", FT_UINT16, BASE_DEC);
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_lapd(void)
|
|
{
|
|
dissector_handle_t lapd_handle;
|
|
|
|
data_handle = find_dissector("data");
|
|
tei_handle = find_dissector("tei");
|
|
|
|
|
|
lapd_handle = create_dissector_handle(dissect_lapd, proto_lapd);
|
|
dissector_add("wtap_encap", WTAP_ENCAP_LINUX_LAPD, lapd_handle);
|
|
}
|