wireshark/epan/dissectors/packet-k12.c

/* packet-k12.c
* Routines for displaying frames from k12 rf5 files
*
* Luis E. Garcia Ontanon <luis.ontanon@gmail.com>
*
* $Id$
*
* 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 <errno.h>
#include <glib.h>
#include <string.h>
#include <epan/packet.h>
#include <prefs.h>
#include <epan/report_err.h>
#include <epan/emem.h>
#include "packet-sscop.h"

static int proto_k12 = -1;

static int hf_k12_port_id = -1;
static int hf_k12_port_name = -1;
static int hf_k12_stack_file = -1;
static int hf_k12_port_type = -1;
static int hf_k12_atm_vp = -1;
static int hf_k12_atm_vc = -1;
static int hf_k12_atm_cid = -1;

static int hf_k12_ts = -1;

static gint ett_k12 = -1;
static gint ett_port = -1;

static dissector_handle_t k12_handle;
static dissector_handle_t data_handle;
static dissector_handle_t sscop_handle;

extern int proto_sscop;

static module_t *k12_module;

static const char* k12_config_filename = "";

static GHashTable* k12_cfg = NULL;


static const value_string  k12_port_types[] = {
	{	K12_PORT_DS1, "Ds1" },
	{	K12_PORT_DS0S, "Ds0 Range" },
	{	K12_PORT_ATMPVC, "ATM PVC" },
	{ 0,NULL}
};


static void dissect_k12(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) {
	proto_item* k12_item;
	proto_tree* k12_tree;
	dissector_handle_t sub_handle;

	k12_item = proto_tree_add_protocol_format(tree, proto_k12, tvb, 0, 0, "Packet from: '%s' (0x%.8x)",
											  pinfo->pseudo_header->k12.input_name,
											  pinfo->pseudo_header->k12.input);

	k12_tree = proto_item_add_subtree(k12_item, ett_k12);

	proto_tree_add_uint(k12_tree, hf_k12_port_id, tvb, 0,0,pinfo->pseudo_header->k12.input);
	proto_tree_add_string(k12_tree, hf_k12_port_name, tvb, 0,0,pinfo->pseudo_header->k12.input_name);
	proto_tree_add_string(k12_tree, hf_k12_stack_file, tvb, 0,0,pinfo->pseudo_header->k12.stack_file);

	k12_item = proto_tree_add_uint(k12_tree, hf_k12_port_type, tvb, 0, 0,
								   pinfo->pseudo_header->k12.input_type);

	k12_tree = proto_item_add_subtree(k12_item, ett_port);

	switch ( pinfo->pseudo_header->k12.input_type ) {
		case K12_PORT_DS0S:
			proto_tree_add_uint(k12_tree, hf_k12_ts, tvb, 0,0,pinfo->pseudo_header->k12.input_info.ds0mask);
			break;
		case K12_PORT_ATMPVC:
        {
            gchar* circuit_str = ep_strdup_printf("%u:%u:%u",
                                                  (guint)pinfo->pseudo_header->k12.input_info.atm.vp,
                                                  (guint)pinfo->pseudo_header->k12.input_info.atm.vc,
                                                  (guint)pinfo->pseudo_header->k12.input_info.atm.cid);
            
			/*
			 * XXX: this is prone to collisions!
			 * we need an uniform way to manage circuits between dissectors
			 */
            pinfo->circuit_id = g_str_hash(circuit_str);
            
			proto_tree_add_uint(k12_tree, hf_k12_atm_vp, tvb, 0,0,pinfo->pseudo_header->k12.input_info.atm.vp);
			proto_tree_add_uint(k12_tree, hf_k12_atm_vc, tvb, 0,0,pinfo->pseudo_header->k12.input_info.atm.vc);
            if (pinfo->pseudo_header->k12.input_info.atm.cid) 
                proto_tree_add_uint(k12_tree, hf_k12_atm_cid, tvb, 0,0,pinfo->pseudo_header->k12.input_info.atm.cid);
			break;
        }
		default:
			break;
	}

	if (! k12_cfg ) {
		sub_handle = data_handle;
	} else {
		dissector_handle_t* handles;
		handles = g_hash_table_lookup(k12_cfg,pinfo->pseudo_header->k12.stack_file);

		if (! handles )
			sub_handle = data_handle;
		else {
			guint i;
			sub_handle = handles[0];
					/* Setup subdissector information */
			for (i = 0; handles[i] && handles[i+1]; ++i) {
				if (handles[i] == sscop_handle) {
					sscop_payload_info *p_sscop_info = p_get_proto_data(pinfo->fd, proto_sscop);
					if (p_sscop_info)
						p_sscop_info->subdissector = handles[i+1];
					else {
						p_sscop_info = se_alloc0(sizeof(sscop_payload_info));
						if (p_sscop_info) {
							p_sscop_info->subdissector = handles[i+1];
							p_add_proto_data(pinfo->fd, proto_sscop, p_sscop_info);
						}
					}
				}
					/* Add more protocols here */
			}
		}
	}

	call_dissector(sub_handle, tvb, pinfo, tree);

}

static gboolean free_key_value (gpointer k, gpointer v _U_, gpointer p _U_) {
	g_free(k);
	g_free(v);
	return TRUE;
}


static GHashTable* k12_load_config(const gchar* filename) {
	FILE* fp;
	gchar buffer[0x10000];
	size_t len;
	GHashTable* hash;
	gchar** curr;
	gchar** protos;
	gchar** lines = NULL;
	guint i, j, k;
	guint num_protos;
	dissector_handle_t *handles;

	/* XXX: should look for the file in common locations */

	if (( fp = fopen(filename,"r") )) {
		len = fread(buffer,1,0xFFFF,fp);
		fclose(fp);
	} else {
		report_open_failure(filename, errno, FALSE);
		return NULL;
	}

	hash = g_hash_table_new(g_str_hash, g_str_equal);

	if (len > 0) {

		lines = g_strsplit(buffer,"\n",0);

		for (i = 0 ; lines[i]; i++) {
			g_strstrip(lines[i]);
			g_strdown(lines[i]);

			if(*(lines[i]) == '#' || *(lines[i]) == '\0')
				continue;

			curr = g_strsplit(lines[i]," ",2);
			g_strstrip(curr[0]);

			if (! (curr[0] != NULL && *(curr[0]) != '\0' && curr[1] != NULL  && *(curr[1]) != '\0' ) ) {
				report_failure("K12xx: Format error in line %u",i+1);
				g_strfreev(curr);
				g_strfreev(lines);
				g_hash_table_foreach_remove(hash,free_key_value,NULL);
				g_hash_table_destroy(hash);
				return NULL;
			}

			protos = g_strsplit(curr[1],":",0);
			for (j = 0; protos[j]; j++)
				g_strstrip(protos[j]);
			num_protos = j;

					/* Allocate extra space for NULL marker */
			handles = g_malloc(sizeof(dissector_handle_t)*(num_protos+1));
			for (j = 0; j <= num_protos; j++)
				handles[j] = NULL;

			for (j = 0; j < num_protos; j++) {
				if (protos[j][0] == '\0') {
					report_failure("K12xx: empty protocol in line %u",i+1);
					break;
				}

				handles[j] = find_dissector(protos[j]);
				if (! handles[j]) {
					report_failure("K12xx: protocol %s not found",protos[j]);
					break;
				}

				if (j > 0) {
					if (handles[j-1] != sscop_handle) {
						report_failure("K12xx: only sscop protocol support subdissector format");
						break;
					}
					if (!sscop_allowed_subdissector(handles[j])) {
						report_failure("K12xx: %s cannot be subdissector of %s",protos[j],protos[j-1]);
						break;
					}
					for (k = 0; k < j; k++)
						if (handles[k] == handles[j]) {
							report_failure("K12xx: cannot nest protocol %s inside itself",protos[j]);
							break;
						}
				}
			}

					/* Revert to data_handle when all
					   protocol seen is error */
			if (handles[0] == NULL)
				handles[0] = data_handle;

			g_hash_table_insert(hash,g_strdup(curr[0]),handles);
			g_strfreev(protos);
			g_strfreev(curr);

		}

		g_strfreev(lines);
		return hash;

	}

	g_hash_table_destroy(hash);

	report_read_failure(filename, errno);

	return NULL;
}

/* Make sure handles for various protocols are initialized */
static void initialize_handles_once(void) {
	static gboolean initialized = FALSE;
	if (!initialized) {
		k12_handle = find_dissector("k12");
		data_handle = find_dissector("data");
		sscop_handle = find_dissector("sscop");
		initialized = TRUE;
	}
}

static void k12_load_prefs(void) {
	if (k12_cfg) {
		g_hash_table_foreach_remove(k12_cfg,free_key_value,NULL);
		g_hash_table_destroy(k12_cfg);
		k12_cfg = NULL;
	}

	if (*k12_config_filename != '\0') {
		initialize_handles_once();
		k12_cfg = k12_load_config(k12_config_filename);
		return;
	}
}

void proto_reg_handoff_k12(void) {
	initialize_handles_once();
	dissector_add("wtap_encap", WTAP_ENCAP_K12, k12_handle);
}

void
proto_register_k12(void)
{
	static hf_register_info hf[] = {
		{ &hf_k12_port_id, { "Port Id", "k12.port_id", FT_UINT32, BASE_HEX,	NULL, 0x0, "", HFILL }},
		{ &hf_k12_port_name, { "Port Name", "k12.port_name", FT_STRING, BASE_NONE, NULL, 0x0,"", HFILL }},
		{ &hf_k12_stack_file, { "Stack file used", "k12.stack_file", FT_STRING, BASE_NONE, NULL, 0x0,"", HFILL }},
		{ &hf_k12_port_type, { "Port type", "k12.input_type", FT_UINT32, BASE_HEX, VALS(k12_port_types), 0x0,"", HFILL }},
		{ &hf_k12_ts, { "Timeslot mask", "k12.ds0.ts", FT_UINT32, BASE_HEX, NULL, 0x0, "", HFILL }},
		{ &hf_k12_atm_vp, { "ATM VPI", "atm.vpi", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
        { &hf_k12_atm_vc, { "ATM VCI", "atm.vci", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }},
        { &hf_k12_atm_cid, { "AAL2 CID", "aal2.cid", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}
	};

  static gint *ett[] = {
	  &ett_k12,
	  &ett_port
  };

  proto_k12 = proto_register_protocol("K12xx", "K12xx", "k12");
  proto_register_field_array(proto_k12, hf, array_length(hf));
  proto_register_subtree_array(ett, array_length(ett));
  register_dissector("k12", dissect_k12, proto_k12);

  k12_module = prefs_register_protocol(proto_k12, k12_load_prefs);

  prefs_register_string_preference(k12_module, "config",
								   "Configuration filename",
								   "K12 module configuration filename",
								   &k12_config_filename);

}