wireshark/epan/dissectors/packet-pgm.c

/* packet-pgm.c
 * Routines for PGM packet disassembly, RFC 3208
 *
 * Copyright (c) 2000 by Talarian Corp
 * Rewritten by Jaap Keuter
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1999 Gerald Combs
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"

#include <epan/packet.h>
#include <epan/afn.h>
#include <epan/ipproto.h>
#include <epan/in_cksum.h>
#include <epan/prefs.h>
#include <epan/ptvcursor.h>
#include <epan/expert.h>

void proto_register_pgm(void);
void proto_reg_handoff_pgm(void);

/*
 * Flag to control whether to check the PGM checksum.
 */
static gboolean pgm_check_checksum = TRUE;

/* constants for hdr types */
#define PGM_SPM_PCKT  0x00
#define PGM_ODATA_PCKT  0x04
#define PGM_RDATA_PCKT  0x05
#define PGM_NAK_PCKT  0x08
#define PGM_NNAK_PCKT  0x09
#define PGM_NCF_PCKT 0x0A
#define PGM_POLL_PCKT 0x01
#define PGM_POLR_PCKT 0x02
#define PGM_ACK_PCKT 0x0D

/* option flags (main PGM header) */
#define PGM_OPT 0x01
#define PGM_OPT_NETSIG 0x02
#define PGM_OPT_VAR_PKTLEN 0x40
#define PGM_OPT_PARITY 0x80

/* option types */
#define PGM_OPT_LENGTH 0x00
#define PGM_OPT_END 0x80
#define PGM_OPT_FRAGMENT 0x01
#define PGM_OPT_NAK_LIST 0x02
#define PGM_OPT_JOIN 0x03
#define PGM_OPT_REDIRECT 0x07
#define PGM_OPT_SYN 0x0D
#define PGM_OPT_FIN 0x0E
#define PGM_OPT_RST 0x0F
#define PGM_OPT_PARITY_PRM 0x08
#define PGM_OPT_PARITY_GRP 0x09
#define PGM_OPT_CURR_TGSIZE 0x0A
#define PGM_OPT_PGMCC_DATA  0x12
#define PGM_OPT_PGMCC_FEEDBACK  0x13
#define PGM_OPT_NAK_BO_IVL 0x04
#define PGM_OPT_NAK_BO_RNG 0x05

/* POLL subtypes */
#define PGM_POLL_GENERAL 0x0
#define PGM_POLL_DLR 0x1

/* OPX bit values */
#define PGM_OPX_IGNORE	0x00
#define PGM_OPX_INVAL	0x01
#define PGM_OPX_DISCARD	0x10

#define PGM_OPT_NAK_LIST_SIZE 4

/*
 * To squeeze the whole option into 255 bytes, we
 * can only have 62 in the list
 */
#define PGM_MAX_NAK_LIST_SZ (62)

#define PGM_OPT_JOIN_SIZE 8
#define PGM_OPT_PARITY_PRM_SIZE 8

/* OPT_PARITY_PRM P and O bits */
#define PGM_OPT_PARITY_PRM_PRO 0x2
#define PGM_OPT_PARITY_PRM_OND 0x1

#define PGM_OPT_PARITY_GRP_SIZE 8
#define PGM_OPT_CURR_TGSIZE_SIZE 8
#define PGM_OPT_PGMCC_DATA_SIZE 16
#define PGM_OPT_PGMCC_FEEDBACK_SIZE 16
#define PGM_OPT_NAK_BO_IVL_SIZE 12
#define PGM_OPT_NAK_BO_RNG_SIZE 12
#define PGM_OPT_REDIRECT_SIZE 12
#define PGM_OPT_FRAGMENT_SIZE 16

/*
 * Udp port for UDP encapsulation
 */
#define DEFAULT_UDP_ENCAP_UCAST_PORT 3055
#define DEFAULT_UDP_ENCAP_MCAST_PORT 3056

static guint udp_encap_ucast_port = 0;
static guint udp_encap_mcast_port = 0;

static int proto_pgm = -1;
static int ett_pgm = -1;
static int ett_pgm_optbits = -1;
static int ett_pgm_opts = -1;
static int ett_pgm_spm = -1;
static int ett_pgm_data = -1;
static int ett_pgm_nak = -1;
static int ett_pgm_poll = -1;
static int ett_pgm_polr = -1;
static int ett_pgm_ack = -1;
static int ett_pgm_opts_join = -1;
static int ett_pgm_opts_parityprm = -1;
static int ett_pgm_opts_paritygrp = -1;
static int ett_pgm_opts_naklist = -1;
static int ett_pgm_opts_ccdata = -1;
static int ett_pgm_opts_nak_bo_ivl = -1;
static int ett_pgm_opts_nak_bo_rng = -1;
static int ett_pgm_opts_redirect = -1;
static int ett_pgm_opts_fragment = -1;

static int hf_pgm_main_sport = -1;
static int hf_pgm_main_dport = -1;
static int hf_pgm_port = -1;
static int hf_pgm_main_type = -1;
static int hf_pgm_main_opts = -1;
static int hf_pgm_main_opts_opt = -1;
static int hf_pgm_main_opts_netsig = -1;
static int hf_pgm_main_opts_varlen = -1;
static int hf_pgm_main_opts_parity = -1;
static int hf_pgm_main_cksum = -1;
static int hf_pgm_main_cksum_status = -1;
static int hf_pgm_main_gsi = -1;
static int hf_pgm_main_tsdulen = -1;
static int hf_pgm_spm_sqn = -1;
static int hf_pgm_spm_lead = -1;
static int hf_pgm_spm_trail = -1;
static int hf_pgm_spm_pathafi = -1;
static int hf_pgm_spm_res = -1;
static int hf_pgm_spm_path = -1;
static int hf_pgm_spm_path6 = -1;
/* static int hf_pgm_data_sqn = -1; */
/* static int hf_pgm_data_trail = -1; */
static int hf_pgm_nak_sqn = -1;
static int hf_pgm_nak_srcafi = -1;
static int hf_pgm_nak_srcres = -1;
static int hf_pgm_nak_src = -1;
static int hf_pgm_nak_src6 = -1;
static int hf_pgm_nak_grpafi = -1;
static int hf_pgm_nak_grpres = -1;
static int hf_pgm_nak_grp = -1;
static int hf_pgm_nak_grp6 = -1;
static int hf_pgm_poll_sqn = -1;
static int hf_pgm_poll_round = -1;
static int hf_pgm_poll_subtype = -1;
static int hf_pgm_poll_pathafi = -1;
static int hf_pgm_poll_res = -1;
static int hf_pgm_poll_path = -1;
static int hf_pgm_poll_path6 = -1;
static int hf_pgm_poll_backoff_ivl = -1;
static int hf_pgm_poll_rand_str = -1;
static int hf_pgm_poll_matching_bmask = -1;
static int hf_pgm_polr_sqn = -1;
static int hf_pgm_polr_round = -1;
static int hf_pgm_polr_res = -1;
static int hf_pgm_ack_sqn = -1;
static int hf_pgm_ack_bitmap = -1;

static int hf_pgm_opt_type = -1;
static int hf_pgm_opt_len = -1;
static int hf_pgm_opt_tlen = -1;

static int hf_pgm_genopt_end = -1;
static int hf_pgm_genopt_type = -1;
static int hf_pgm_genopt_len = -1;
static int hf_pgm_genopt_opx = -1;

static int hf_pgm_opt_join_res = -1;
static int hf_pgm_opt_join_minjoin = -1;

static int hf_pgm_opt_parity_prm_po = -1;
static int hf_pgm_opt_parity_prm_prmtgsz = -1;

static int hf_pgm_opt_parity_grp_res = -1;
static int hf_pgm_opt_parity_grp_prmgrp = -1;

static int hf_pgm_opt_nak_res = -1;
static int hf_pgm_opt_nak_list = -1;

static int hf_pgm_opt_ccdata_res = -1;
static int hf_pgm_opt_ccdata_tsp = -1;
static int hf_pgm_opt_ccdata_afi = -1;
static int hf_pgm_opt_ccdata_res2 = -1;
static int hf_pgm_opt_ccdata_acker = -1;
static int hf_pgm_opt_ccdata_acker6 = -1;

static int hf_pgm_opt_ccfeedbk_res = -1;
static int hf_pgm_opt_ccfeedbk_tsp = -1;
static int hf_pgm_opt_ccfeedbk_afi = -1;
static int hf_pgm_opt_ccfeedbk_lossrate = -1;
static int hf_pgm_opt_ccfeedbk_acker = -1;
static int hf_pgm_opt_ccfeedbk_acker6 = -1;

static int hf_pgm_opt_nak_bo_ivl_res = -1;
static int hf_pgm_opt_nak_bo_ivl_bo_ivl = -1;
static int hf_pgm_opt_nak_bo_ivl_bo_ivl_sqn = -1;

static int hf_pgm_opt_nak_bo_rng_res = -1;
static int hf_pgm_opt_nak_bo_rng_min_bo_ivl = -1;
static int hf_pgm_opt_nak_bo_rng_max_bo_ivl = -1;

static int hf_pgm_opt_redirect_res = -1;
static int hf_pgm_opt_redirect_afi = -1;
static int hf_pgm_opt_redirect_res2 = -1;
static int hf_pgm_opt_redirect_dlr = -1;
static int hf_pgm_opt_redirect_dlr6 = -1;

static int hf_pgm_opt_fragment_res = -1;
static int hf_pgm_opt_fragment_first_sqn = -1;
static int hf_pgm_opt_fragment_offset = -1;
static int hf_pgm_opt_fragment_total_length = -1;

static expert_field ei_pgm_genopt_len = EI_INIT;
static expert_field ei_pgm_opt_tlen = EI_INIT;
static expert_field ei_pgm_opt_type = EI_INIT;
static expert_field ei_address_format_invalid = EI_INIT;

static dissector_table_t subdissector_table;
static heur_dissector_list_t heur_subdissector_list;


static const char *
optsstr(guint8 opts)
{
	char *msg;
	gint  returned_length, idx = 0;
	const int MAX_STR_LEN = 256;

	if (opts == 0)
		return("");

	msg=(char *)wmem_alloc(wmem_packet_scope(), MAX_STR_LEN);
	if (opts & PGM_OPT){
		returned_length = g_snprintf(&msg[idx], MAX_STR_LEN-idx, "Present");
		idx += MIN(returned_length, MAX_STR_LEN-idx);
	}
	if (opts & PGM_OPT_NETSIG){
		returned_length = g_snprintf(&msg[idx], MAX_STR_LEN-idx, "%sNetSig", (!idx)?"":",");
		idx += MIN(returned_length, MAX_STR_LEN-idx);
	}
	if (opts & PGM_OPT_VAR_PKTLEN){
		returned_length = g_snprintf(&msg[idx], MAX_STR_LEN-idx, "%sVarLen", (!idx)?"":",");
		idx += MIN(returned_length, MAX_STR_LEN-idx);
	}
	if (opts & PGM_OPT_PARITY){
		returned_length = g_snprintf(&msg[idx], MAX_STR_LEN-idx, "%sParity", (!idx)?"":",");
		idx += MIN(returned_length, MAX_STR_LEN-idx);
	}
	if (!idx) {
		g_snprintf(&msg[idx], MAX_STR_LEN-idx, "0x%x", opts);
	}
	return(msg);
}
static const char *
paritystr(guint8 parity)
{
	char *msg;
	gint returned_length, idx = 0;
	const int MAX_STR_LEN = 256;

	if (parity == 0)
		return("");

	msg=(char *)wmem_alloc(wmem_packet_scope(), MAX_STR_LEN);
	if (parity & PGM_OPT_PARITY_PRM_PRO){
		returned_length = g_snprintf(&msg[idx], MAX_STR_LEN-idx, "Pro-active");
		idx += MIN(returned_length, MAX_STR_LEN-idx);
	}
	if (parity & PGM_OPT_PARITY_PRM_OND){
		returned_length = g_snprintf(&msg[idx], MAX_STR_LEN-idx, "%sOn-demand", (!idx)?"":",");
		idx += MIN(returned_length, MAX_STR_LEN-idx);
	}
	if (!idx) {
		g_snprintf(&msg[idx], MAX_STR_LEN-idx, "0x%x", parity);
	}
	return(msg);
}

static const value_string opt_vals[] = {
	{ PGM_OPT_LENGTH,	  "Length" },
	{ PGM_OPT_END,		  "End" },
	{ PGM_OPT_FRAGMENT,	  "Fragment" },
	{ PGM_OPT_NAK_LIST,	  "NakList" },
	{ PGM_OPT_JOIN,		  "Join" },
	{ PGM_OPT_REDIRECT,	  "ReDirect" },
	{ PGM_OPT_SYN,		  "Syn" },
	{ PGM_OPT_FIN,		  "Fin" },
	{ PGM_OPT_RST,		  "Rst" },
	{ PGM_OPT_PARITY_PRM,	  "ParityPrm" },
	{ PGM_OPT_PARITY_GRP,	  "ParityGrp" },
	{ PGM_OPT_CURR_TGSIZE,	  "CurrTgsiz" },
	{ PGM_OPT_PGMCC_DATA,	  "CcData" },
	{ PGM_OPT_PGMCC_FEEDBACK, "CcFeedBack" },
	{ PGM_OPT_NAK_BO_IVL,	  "NakBackOffIvl" },
	{ PGM_OPT_NAK_BO_RNG,	  "NakBackOffRng" },
	{ PGM_OPT_FRAGMENT,	  "Fragment" },
	{ 0,                   NULL }
};

static const value_string opx_vals[] = {
	{ PGM_OPX_IGNORE,  "Ignore" },
	{ PGM_OPX_INVAL,   "Inval" },
	{ PGM_OPX_DISCARD, "DisCard" },
	{ 0,               NULL }
};

static const true_false_string opts_present = {
	"Present",
	"Not Present"
};

#define TLV_CHECK(ett) \
	opt_tree = proto_tree_add_subtree_format(opts_tree, tvb, ptvcursor_current_offset(cursor), genopts_len, \
						ett, &tf, "Option: %s, Length: %u", \
						val_to_str(genopts_type, opt_vals, "Unknown (0x%02x)"), genopts_len); \
	if (genopts_len < 4) { \
		expert_add_info_format(pinfo, tf, &ei_pgm_genopt_len, \
					"Length %u invalid, must be >= 4", genopts_len); \
		return; \
	} \
	if (opts_total_len < genopts_len) { \
		expert_add_info_format(pinfo, tf, &ei_pgm_genopt_len, \
					"Length %u > remaining total options length", genopts_len); \
		return; \
	} \


static void
dissect_pgmopts(ptvcursor_t* cursor, packet_info *pinfo, const char *pktname)
{
	proto_item *tf, *ti, *ti_len;
	proto_tree *opts_tree = NULL;
	proto_tree *opt_tree  = NULL;
	tvbuff_t   *tvb       = ptvcursor_tvbuff(cursor);

	gboolean theend = FALSE;

	guint16 opts_total_len;
	guint8  genopts_type;
	guint8  genopts_len;
	guint8  opts_type;

	opts_tree = proto_tree_add_subtree_format(ptvcursor_tree(cursor), tvb, ptvcursor_current_offset(cursor), -1,
		ett_pgm_opts, &tf, "%s Options", pktname);
	ptvcursor_set_tree(cursor, opts_tree);
	opts_type = tvb_get_guint8(tvb, ptvcursor_current_offset(cursor));
	ti = ptvcursor_add(cursor, hf_pgm_opt_type, 1, ENC_BIG_ENDIAN);
	if (opts_type != PGM_OPT_LENGTH) {
		expert_add_info_format(pinfo, ti, &ei_pgm_opt_type,
		    "%s Options - initial option is %s, should be %s",
		    pktname,
		    val_to_str(opts_type, opt_vals, "Unknown (0x%02x)"),
		    val_to_str(PGM_OPT_LENGTH, opt_vals, "Unknown (0x%02x)"));
		return;
	}
	ptvcursor_add(cursor, hf_pgm_opt_len, 1, ENC_BIG_ENDIAN);
	opts_total_len = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
	proto_item_append_text(tf, " (Total Length %d)", opts_total_len);
	proto_item_set_len(tf, opts_total_len);
	ti_len = ptvcursor_add(cursor, hf_pgm_opt_tlen, 2, ENC_BIG_ENDIAN);
	if (opts_total_len < 4) {
		expert_add_info_format(pinfo, ti_len, &ei_pgm_opt_tlen,
			"%s Options (Total Length %u - invalid, must be >= 4)",
			pktname, opts_total_len);
		return;
	}

	for (opts_total_len -= 4; !theend && opts_total_len != 0;){
		if (opts_total_len < 4) {
			expert_add_info_format(pinfo, ti_len, &ei_pgm_opt_tlen,
				"Remaining total options length doesn't have enough for an options header");
			break;
		}

		genopts_type = tvb_get_guint8(tvb, ptvcursor_current_offset(cursor));
		genopts_len = tvb_get_guint8(tvb, ptvcursor_current_offset(cursor)+1);

		if (genopts_type & PGM_OPT_END)  {
			genopts_type &= ~PGM_OPT_END;
			theend = TRUE;
		}

		switch(genopts_type) {
		case PGM_OPT_JOIN:{
			TLV_CHECK(ett_pgm_opts_join);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_JOIN_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_JOIN_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_join_res, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_join_minjoin, 4, ENC_BIG_ENDIAN);

			break;
		}
		case PGM_OPT_PARITY_PRM:{
			guint8 optdata_po;

			TLV_CHECK(ett_pgm_opts_parityprm);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);


			if (genopts_len < PGM_OPT_PARITY_PRM_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, ptvcursor_tvbuff(cursor),
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_PARITY_PRM_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			optdata_po = tvb_get_guint8(tvb, ptvcursor_current_offset(cursor));
			proto_tree_add_uint_format_value(opt_tree, hf_pgm_opt_parity_prm_po, tvb,
				ptvcursor_current_offset(cursor), 1, optdata_po, "%s (0x%x)",
				paritystr(optdata_po), optdata_po);
			ptvcursor_advance(cursor, 1);

			ptvcursor_add(cursor, hf_pgm_opt_parity_prm_prmtgsz, 4, ENC_BIG_ENDIAN);

			break;
		}
		case PGM_OPT_PARITY_GRP:{
			TLV_CHECK(ett_pgm_opts_paritygrp);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_PARITY_GRP_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_PARITY_GRP_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_parity_grp_res, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_parity_grp_prmgrp, 4, ENC_BIG_ENDIAN);

			break;
		}
		case PGM_OPT_NAK_LIST:{
			guint8 optdata_len;
			guint32 naklist[PGM_MAX_NAK_LIST_SZ+1];
			unsigned char *nakbuf;
			gboolean firsttime;
			int i, j, naks, soffset;

			TLV_CHECK(ett_pgm_opts_naklist);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			optdata_len = tvb_get_guint8(tvb, ptvcursor_current_offset(cursor));
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_nak_res, 1, ENC_BIG_ENDIAN);

			optdata_len -= PGM_OPT_NAK_LIST_SIZE;
			tvb_memcpy(tvb, (guint8 *)naklist, ptvcursor_current_offset(cursor), optdata_len);
			firsttime = TRUE;
			soffset = 0;
			naks = (int)(optdata_len/sizeof(guint32));
			nakbuf = (unsigned char *)wmem_alloc(wmem_packet_scope(), 8192);
			j = 0;
			/*
			 * Print out 8 per line
			 */
			for (i=0; i < naks; i++) {
				soffset += MIN(8192-soffset,
					g_snprintf(nakbuf+soffset, 8192-soffset, "0x%lx ",
						(unsigned long)g_ntohl(naklist[i])));
				if ((++j % 8) == 0) {
					if (firsttime) {
						proto_tree_add_bytes_format(opt_tree,
							hf_pgm_opt_nak_list, tvb, ptvcursor_current_offset(cursor), j*4,
							nakbuf, "List(%d): %s", naks, nakbuf);
						soffset = 0;
						firsttime = FALSE;
					} else {
						proto_tree_add_bytes_format_value(opt_tree,
							hf_pgm_opt_nak_list, tvb, ptvcursor_current_offset(cursor), j*4,
							nakbuf, "%s", nakbuf);
						soffset = 0;
					}
					ptvcursor_advance(cursor, j*4);
					j = 0;
				}
			}
			if (j) {
				if (firsttime) {
					proto_tree_add_bytes_format(opt_tree,
						hf_pgm_opt_nak_list, tvb, ptvcursor_current_offset(cursor), j*4,
						nakbuf, "List(%d): %s", naks, nakbuf);
				} else {
					proto_tree_add_bytes_format_value(opt_tree,
						hf_pgm_opt_nak_list, tvb, ptvcursor_current_offset(cursor), j*4,
						nakbuf, "%s", nakbuf);
				}
				ptvcursor_advance(cursor, j*4);
			}
			break;
		}
		case PGM_OPT_PGMCC_DATA:{
			guint16 optdata_afi;

			TLV_CHECK(ett_pgm_opts_ccdata);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_PGMCC_DATA_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_PGMCC_DATA_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_ccdata_res, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_ccdata_tsp, 4, ENC_BIG_ENDIAN);
			optdata_afi = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
			ti = ptvcursor_add(cursor, hf_pgm_opt_ccdata_afi, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_ccdata_res2, 2, ENC_BIG_ENDIAN);

			switch (optdata_afi) {

			case AFNUM_INET:
				ptvcursor_add(cursor, hf_pgm_opt_ccdata_acker, 4, ENC_BIG_ENDIAN);
				break;

			case AFNUM_INET6:
				ptvcursor_add(cursor, hf_pgm_opt_ccdata_acker6, 16, ENC_NA);
				break;

			default:
				expert_add_info(pinfo, ti, &ei_address_format_invalid);
				break;
			}

			break;
		}
		case PGM_OPT_PGMCC_FEEDBACK:{
			guint16 optdata_afi;

			TLV_CHECK(ett_pgm_opts_ccdata);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_PGMCC_FEEDBACK_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_PGMCC_FEEDBACK_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_ccfeedbk_res, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_ccfeedbk_tsp, 4, ENC_BIG_ENDIAN);
			optdata_afi = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
			ti = ptvcursor_add(cursor, hf_pgm_opt_ccfeedbk_afi, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_ccfeedbk_lossrate, 2, ENC_BIG_ENDIAN);

			switch (optdata_afi) {

			case AFNUM_INET:
				ptvcursor_add(cursor, hf_pgm_opt_ccfeedbk_acker, 4, ENC_BIG_ENDIAN);
				break;

			case AFNUM_INET6:
				ptvcursor_add(cursor, hf_pgm_opt_ccfeedbk_acker6, 16, ENC_NA);
				break;

			default:
				expert_add_info(pinfo, ti, &ei_address_format_invalid);
				break;
			}

			break;
		}
		case PGM_OPT_NAK_BO_IVL:{
			TLV_CHECK(ett_pgm_opts_nak_bo_ivl);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_NAK_BO_IVL_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_NAK_BO_IVL_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_nak_bo_ivl_res, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_nak_bo_ivl_bo_ivl, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_nak_bo_ivl_bo_ivl_sqn, 4, ENC_BIG_ENDIAN);

			break;
		}
		case PGM_OPT_NAK_BO_RNG:{
			TLV_CHECK(ett_pgm_opts_nak_bo_rng);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_NAK_BO_RNG_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_NAK_BO_RNG_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_nak_bo_rng_res, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_nak_bo_rng_min_bo_ivl, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_nak_bo_rng_max_bo_ivl, 4, ENC_BIG_ENDIAN);

			break;
		}
		case PGM_OPT_REDIRECT:{
			guint16 optdata_afi;

			TLV_CHECK(ett_pgm_opts_redirect);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_REDIRECT_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_REDIRECT_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_redirect_res, 1, ENC_BIG_ENDIAN);
			optdata_afi = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
			ti = ptvcursor_add(cursor, hf_pgm_opt_redirect_afi, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_redirect_res2, 2, ENC_BIG_ENDIAN);

			switch (optdata_afi) {

			case AFNUM_INET:
				ptvcursor_add(cursor, hf_pgm_opt_redirect_dlr, 4, ENC_BIG_ENDIAN);
				break;

			case AFNUM_INET6:
				ptvcursor_add(cursor, hf_pgm_opt_redirect_dlr6, 16, ENC_NA);
				break;

			default:
				expert_add_info(pinfo, ti, &ei_address_format_invalid);
				break;
			}

			break;
		}
		case PGM_OPT_FRAGMENT:{
			TLV_CHECK(ett_pgm_opts_fragment);
			ptvcursor_set_tree(cursor, opt_tree);

			ptvcursor_add_no_advance(cursor, hf_pgm_genopt_end, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_type, 1, ENC_BIG_ENDIAN);

			if (genopts_len < PGM_OPT_FRAGMENT_SIZE) {
				proto_tree_add_uint_format_value(opt_tree, hf_pgm_genopt_len, tvb,
					ptvcursor_current_offset(cursor), 1, genopts_len,
					"%u (bogus, must be >= %u)",
					genopts_len, PGM_OPT_FRAGMENT_SIZE);
				break;
			}
			ptvcursor_add(cursor, hf_pgm_genopt_len, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_genopt_opx, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_fragment_res, 1, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_fragment_first_sqn, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_fragment_offset, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_opt_fragment_total_length, 4, ENC_BIG_ENDIAN);

			break;
		}
		default:{
			TLV_CHECK(ett_pgm_opts);
			ptvcursor_advance(cursor, genopts_len);
			break;
		}
		}

		opts_total_len -= genopts_len;
	}
	return;
}

static const value_string type_vals[] = {
	{ PGM_SPM_PCKT,   "SPM" },
	{ PGM_RDATA_PCKT, "RDATA" },
	{ PGM_ODATA_PCKT, "ODATA" },
	{ PGM_NAK_PCKT,   "NAK" },
	{ PGM_NNAK_PCKT,  "NNAK" },
	{ PGM_NCF_PCKT,   "NCF" },
	{ PGM_POLL_PCKT,  "POLL" },
	{ PGM_POLR_PCKT,  "POLR" },
	{ PGM_ACK_PCKT,   "ACK" },
	{ 0,              NULL }
};

static const value_string poll_subtype_vals[] = {
	{ PGM_POLL_GENERAL,   "General" },
	{ PGM_POLL_DLR,       "DLR" },
	{ 0,                  NULL }
};

/* Determine if there is a sub-dissector and call it.  This has been */
/* separated into a stand alone routine to other protocol dissectors */
/* can call to it, ie. socks	*/

static void
decode_pgm_ports(tvbuff_t *tvb, int offset, packet_info *pinfo,
		 proto_tree *tree, guint16 pgmhdr_sport, guint16 pgmhdr_dport)
{
	tvbuff_t *next_tvb;
	int       found = 0;
	heur_dtbl_entry_t *hdtbl_entry;

	next_tvb = tvb_new_subset_remaining(tvb, offset);

	/* do lookup with the subdissector table */
	found = dissector_try_uint(subdissector_table, pgmhdr_sport,
				   next_tvb, pinfo, tree);
	if (found)
		return;

	found = dissector_try_uint(subdissector_table, pgmhdr_dport,
				   next_tvb, pinfo, tree);
	if (found)
		return;

	/* do lookup with the heuristic subdissector table */
	if (dissector_try_heuristic(heur_subdissector_list, next_tvb, pinfo, tree, &hdtbl_entry, NULL))
		return;

	/* Oh, well, we don't know this; dissect it as data. */
	call_data_dissector(next_tvb, pinfo, tree);
}

/*
 * dissect_pgm - The dissector for Pragmatic General Multicast
 */
static int
dissect_pgm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
	guint16 pgmhdr_sport;
	guint16 pgmhdr_dport;
	guint8  pgmhdr_type;
	guint8  pgmhdr_opts;
	guint16 pgmhdr_cksum;
	guint16 pgmhdr_tsdulen;
	guint32 sqn;
	guint16 afi;

	guint       plen   = 0;
	proto_item *ti;
	const char *pktname;
	const char *pollstname;
	char       *gsi;
	gboolean    isdata = FALSE;
	guint       pgmlen, reportedlen;

	if (tvb_reported_length_remaining(tvb, 0) < 18)
		return 0;

	col_set_str(pinfo->cinfo, COL_PROTOCOL, "PGM");
	col_clear(pinfo->cinfo, COL_INFO);

	pinfo->srcport = pgmhdr_sport = tvb_get_ntohs(tvb, 0);
	pinfo->destport = pgmhdr_dport = tvb_get_ntohs(tvb, 2);

	pgmhdr_type = tvb_get_guint8(tvb, 4);
	pktname = val_to_str(pgmhdr_type, type_vals, "Unknown (0x%02x)");

	pgmhdr_opts = tvb_get_guint8(tvb, 5);
	pgmhdr_cksum = tvb_get_ntohs(tvb, 6);
	gsi = tvb_bytes_to_str(wmem_packet_scope(), tvb, 8, 6);
	pgmhdr_tsdulen = tvb_get_ntohs(tvb, 14);
	sqn = tvb_get_ntohl(tvb, 16);

	switch(pgmhdr_type) {
	case PGM_SPM_PCKT:
	case PGM_NAK_PCKT:
	case PGM_NNAK_PCKT:
	case PGM_NCF_PCKT:
	case PGM_POLR_PCKT:
	case PGM_ACK_PCKT:
		col_add_fstr(pinfo->cinfo, COL_INFO,
				"%-5s sqn 0x%x gsi %s", pktname, sqn, gsi);
		break;
	case PGM_RDATA_PCKT:
	case PGM_ODATA_PCKT:
		col_add_fstr(pinfo->cinfo, COL_INFO,
			    "%-5s sqn 0x%x gsi %s tsdulen %d", pktname, sqn, gsi,
			    pgmhdr_tsdulen);

		isdata = TRUE;
		break;
	case PGM_POLL_PCKT: {
		guint16 poll_stype = tvb_get_ntohs(tvb, 22);
		pollstname = val_to_str(poll_stype, poll_subtype_vals, "Unknown (0x%02x)");

		col_add_fstr(pinfo->cinfo, COL_INFO,
				"%-5s sqn 0x%x gsi %s subtype %s",
					pktname, sqn, gsi, pollstname);
		}
		break;
	default:
		return 20;
	}

	{
		proto_tree *pgm_tree = NULL;
		proto_tree *opt_tree = NULL;
		proto_tree *type_tree = NULL;
		proto_item *tf, *hidden_item;
		ptvcursor_t* cursor;

		ti = proto_tree_add_protocol_format(tree, proto_pgm,
			tvb, 0, -1,
			"Pragmatic General Multicast: Type %s"
			    " Src Port %u, Dst Port %u, GSI %s", pktname,
			pgmhdr_sport, pgmhdr_dport, gsi);

		pgm_tree = proto_item_add_subtree(ti, ett_pgm);

		cursor = ptvcursor_new(pgm_tree, tvb, 0);

		hidden_item = proto_tree_add_item(pgm_tree, hf_pgm_port, tvb, 0, 2, ENC_BIG_ENDIAN);
		PROTO_ITEM_SET_HIDDEN(hidden_item);
		hidden_item = proto_tree_add_item(pgm_tree, hf_pgm_port, tvb, 2, 2, ENC_BIG_ENDIAN);
		PROTO_ITEM_SET_HIDDEN(hidden_item);
		ptvcursor_add(cursor, hf_pgm_main_sport, 2, ENC_BIG_ENDIAN);
		ptvcursor_add(cursor, hf_pgm_main_dport, 2, ENC_BIG_ENDIAN);
		ptvcursor_add(cursor, hf_pgm_main_type, 1, ENC_BIG_ENDIAN);

		tf = proto_tree_add_uint_format_value(pgm_tree, hf_pgm_main_opts, tvb,
			ptvcursor_current_offset(cursor), 1, pgmhdr_opts, "%s (0x%x)",
			optsstr(pgmhdr_opts), pgmhdr_opts);
		opt_tree = proto_item_add_subtree(tf, ett_pgm_optbits);
		ptvcursor_set_tree(cursor, opt_tree);

		ptvcursor_add_no_advance(cursor, hf_pgm_main_opts_opt, 1, ENC_BIG_ENDIAN);
		ptvcursor_add_no_advance(cursor, hf_pgm_main_opts_netsig, 1, ENC_BIG_ENDIAN);
		ptvcursor_add_no_advance(cursor, hf_pgm_main_opts_varlen, 1, ENC_BIG_ENDIAN);
		ptvcursor_add(cursor, hf_pgm_main_opts_parity, 1, ENC_BIG_ENDIAN);
		ptvcursor_set_tree(cursor, pgm_tree);

		/* Checksum may be 0 (not available), but not for DATA packets */
		if ((pgmhdr_type != PGM_RDATA_PCKT) && (pgmhdr_type != PGM_ODATA_PCKT) &&
		    (pgmhdr_cksum == 0))
		{
			proto_tree_add_checksum(pgm_tree, tvb, ptvcursor_current_offset(cursor), hf_pgm_main_cksum, hf_pgm_main_cksum_status, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NOT_PRESENT);
		} else {
			reportedlen = tvb_reported_length(tvb);
			pgmlen = tvb_captured_length(tvb);
			if (pgm_check_checksum && pgmlen >= reportedlen) {
				vec_t cksum_vec[1];

				SET_CKSUM_VEC_TVB(cksum_vec[0], tvb, 0, pgmlen);
				proto_tree_add_checksum(pgm_tree, tvb, ptvcursor_current_offset(cursor), hf_pgm_main_cksum_status, -1, NULL, pinfo,
										in_cksum(&cksum_vec[0], 1), ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_IN_CKSUM);
			} else {
				proto_tree_add_checksum(pgm_tree, tvb, ptvcursor_current_offset(cursor), hf_pgm_main_cksum, hf_pgm_main_cksum_status, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
			}
		}
		ptvcursor_advance(cursor, 2);

		ptvcursor_add(cursor, hf_pgm_main_gsi, 6, ENC_NA);
		ptvcursor_add(cursor, hf_pgm_main_tsdulen, 2, ENC_BIG_ENDIAN);

		switch(pgmhdr_type) {
		case PGM_SPM_PCKT:
			type_tree = proto_tree_add_subtree_format(pgm_tree, tvb, ptvcursor_current_offset(cursor), plen,
												ett_pgm_spm, NULL, "%s Packet", pktname);
			ptvcursor_set_tree(cursor, type_tree);

			ptvcursor_add(cursor, hf_pgm_spm_sqn, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_spm_trail, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_spm_lead, 4, ENC_BIG_ENDIAN);
			afi = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
			ti = ptvcursor_add(cursor, hf_pgm_spm_pathafi, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_spm_res, 2, ENC_BIG_ENDIAN);

			switch (afi) {
			case AFNUM_INET:
				ptvcursor_add(cursor, hf_pgm_spm_path, 4, ENC_BIG_ENDIAN);
				break;

			case AFNUM_INET6:
				ptvcursor_add(cursor, hf_pgm_spm_path6, 16, ENC_NA);
				break;

			default:
				expert_add_info(pinfo, ti, &ei_address_format_invalid);
				ptvcursor_free(cursor);
				return tvb_captured_length(tvb);
			}
			break;
		case PGM_RDATA_PCKT:
		case PGM_ODATA_PCKT:
			type_tree = proto_tree_add_subtree_format(pgm_tree, tvb, ptvcursor_current_offset(cursor), plen,
												ett_pgm_data, NULL, "%s Packet", pktname);
			ptvcursor_set_tree(cursor, type_tree);

			ptvcursor_add(cursor, hf_pgm_spm_sqn, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_spm_trail, 4, ENC_BIG_ENDIAN);
			break;
		case PGM_NAK_PCKT:
		case PGM_NNAK_PCKT:
		case PGM_NCF_PCKT:
			type_tree = proto_tree_add_subtree_format(pgm_tree, tvb, ptvcursor_current_offset(cursor), plen,
												ett_pgm_nak, NULL, "%s Packet", pktname);
			ptvcursor_set_tree(cursor, type_tree);

			ptvcursor_add(cursor, hf_pgm_nak_sqn, 4, ENC_BIG_ENDIAN);
			afi = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
			ti = ptvcursor_add(cursor, hf_pgm_nak_srcafi, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_nak_srcres, 2, ENC_BIG_ENDIAN);

			switch (afi) {
			case AFNUM_INET:
				ptvcursor_add(cursor, hf_pgm_nak_src, 4, ENC_BIG_ENDIAN);
				break;

			case AFNUM_INET6:
				ptvcursor_add(cursor, hf_pgm_nak_src6, 16, ENC_NA);
				break;

			default:
				expert_add_info(pinfo, ti, &ei_address_format_invalid);
				break;
			}

			afi = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
			ti = ptvcursor_add(cursor, hf_pgm_nak_grpafi, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_nak_grpres, 2, ENC_BIG_ENDIAN);

			switch (afi) {
			case AFNUM_INET:
				ptvcursor_add(cursor, hf_pgm_nak_grp, 4, ENC_BIG_ENDIAN);
				break;

			case AFNUM_INET6:
				ptvcursor_add(cursor, hf_pgm_nak_grp6, 16, ENC_NA);
				break;

			default:
				expert_add_info(pinfo, ti, &ei_address_format_invalid);
				ptvcursor_free(cursor);
				return tvb_captured_length(tvb);
			}
			break;
		case PGM_POLL_PCKT:
			type_tree = proto_tree_add_subtree_format(pgm_tree, tvb, ptvcursor_current_offset(cursor), plen,
												ett_pgm_poll, NULL, "%s Packet", pktname);
			ptvcursor_set_tree(cursor, type_tree);

			ptvcursor_add(cursor, hf_pgm_poll_sqn, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_poll_round, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_poll_subtype, 2, ENC_BIG_ENDIAN);
			afi = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor));
			ti = ptvcursor_add(cursor, hf_pgm_poll_pathafi, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_poll_res, 2, ENC_BIG_ENDIAN);

			switch (afi) {
			case AFNUM_INET:
				ptvcursor_add(cursor, hf_pgm_poll_path, 4, ENC_BIG_ENDIAN);
				break;

			case AFNUM_INET6:
				ptvcursor_add(cursor, hf_pgm_poll_path6, 16, ENC_NA);
				break;

			default:
				expert_add_info(pinfo, ti, &ei_address_format_invalid);
				break;
			}

			ptvcursor_add(cursor, hf_pgm_poll_backoff_ivl, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_poll_rand_str, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_poll_matching_bmask, 4, ENC_BIG_ENDIAN);
			break;
		case PGM_POLR_PCKT:
			type_tree = proto_tree_add_subtree_format(pgm_tree, tvb, ptvcursor_current_offset(cursor), plen,
												ett_pgm_polr, NULL, "%s Packet", pktname);
			ptvcursor_set_tree(cursor, type_tree);

			ptvcursor_add(cursor, hf_pgm_polr_sqn, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_polr_round, 2, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_polr_res, 2, ENC_BIG_ENDIAN);
			break;
		case PGM_ACK_PCKT:
			type_tree = proto_tree_add_subtree_format(pgm_tree, tvb, ptvcursor_current_offset(cursor), plen,
												ett_pgm_ack, NULL, "%s Packet", pktname);
			ptvcursor_set_tree(cursor, type_tree);

			ptvcursor_add(cursor, hf_pgm_ack_sqn, 4, ENC_BIG_ENDIAN);
			ptvcursor_add(cursor, hf_pgm_ack_bitmap, 4, ENC_BIG_ENDIAN);
			break;
		}

		if (pgmhdr_opts & PGM_OPT)
			dissect_pgmopts(cursor, pinfo, pktname);

		if (isdata)
			decode_pgm_ports(tvb, ptvcursor_current_offset(cursor), pinfo, tree, pgmhdr_sport, pgmhdr_dport);

		ptvcursor_free(cursor);
	}
	return tvb_captured_length(tvb);
}

/* Register all the bits needed with the filtering engine */
void
proto_register_pgm(void)
{
	static hf_register_info hf[] = {
		{ &hf_pgm_main_sport,
		  { "Source Port", "pgm.hdr.sport", FT_UINT16, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_main_dport,
		  { "Destination Port", "pgm.hdr.dport", FT_UINT16, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_port,
		  { "Port", "pgm.port", FT_UINT16, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_main_type,
		  { "Type", "pgm.hdr.type", FT_UINT8, BASE_HEX,
		    VALS(type_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_main_opts,
		  { "Options", "pgm.hdr.opts", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_main_opts_opt,
		  { "Options", "pgm.hdr.opts.opt", FT_BOOLEAN, 8,
		    TFS(&opts_present), PGM_OPT, NULL, HFILL }},
		{ &hf_pgm_main_opts_netsig,
		  { "Network Significant Options", "pgm.hdr.opts.netsig",
		    FT_BOOLEAN, 8,
		    TFS(&opts_present), PGM_OPT_NETSIG, NULL, HFILL }},
		{ &hf_pgm_main_opts_varlen,
		  { "Variable length Parity Packet Option", "pgm.hdr.opts.varlen",
		    FT_BOOLEAN, 8,
		    TFS(&opts_present), PGM_OPT_VAR_PKTLEN, NULL, HFILL }},
		{ &hf_pgm_main_opts_parity,
		  { "Parity", "pgm.hdr.opts.parity", FT_BOOLEAN, 8,
		    TFS(&opts_present), PGM_OPT_PARITY, NULL, HFILL }},
		{ &hf_pgm_main_cksum,
		  { "Checksum", "pgm.hdr.cksum", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_main_cksum_status,
		  { "Checksum Status", "pgm.hdr.cksum.status", FT_UINT8, BASE_NONE,
		    VALS(proto_checksum_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_main_gsi,
		  { "Global Source Identifier", "pgm.hdr.gsi", FT_BYTES, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_main_tsdulen,
		  { "Transport Service Data Unit Length", "pgm.hdr.tsdulen", FT_UINT16,
		    BASE_DEC, NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_spm_sqn,
		  { "Sequence number", "pgm.spm.sqn", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_spm_trail,
		  { "Trailing Edge Sequence Number", "pgm.spm.trail", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_spm_lead,
		  { "Leading Edge Sequence Number", "pgm.spm.lead", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_spm_pathafi,
		  { "Path NLA AFI", "pgm.spm.pathafi", FT_UINT16, BASE_DEC,
		    VALS(afn_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_spm_res,
		  { "Reserved", "pgm.spm.res", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_spm_path,
		  { "Path NLA", "pgm.spm.path.ipv4", FT_IPv4, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_spm_path6,
		  { "Path NLA", "pgm.spm.path.ipv6", FT_IPv6, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
#if 0
		{ &hf_pgm_data_sqn,
		  { "Data Packet Sequence Number", "pgm.data.sqn", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
#endif
#if 0
		{ &hf_pgm_data_trail,
		  { "Trailing Edge Sequence Number", "pgm.data.trail", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
#endif
		{ &hf_pgm_nak_sqn,
		  { "Requested Sequence Number", "pgm.nak.sqn", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_srcafi,
		  { "Source NLA AFI", "pgm.nak.srcafi", FT_UINT16, BASE_DEC,
		    VALS(afn_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_srcres,
		  { "Reserved", "pgm.nak.srcres", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_src,
		  { "Source NLA", "pgm.nak.src.ipv4", FT_IPv4, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_src6,
		  { "Source NLA", "pgm.nak.src.ipv6", FT_IPv6, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_grpafi,
		  { "Multicast Group AFI", "pgm.nak.grpafi", FT_UINT16, BASE_DEC,
		    VALS(afn_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_grpres,
		  { "Reserved", "pgm.nak.grpres", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_grp,
		  { "Multicast Group NLA", "pgm.nak.grp.ipv4", FT_IPv4, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_nak_grp6,
		  { "Multicast Group NLA", "pgm.nak.grp.ipv6", FT_IPv6, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_sqn,
		  { "Sequence Number", "pgm.poll.sqn", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_round,
		  { "Round", "pgm.poll.round", FT_UINT16, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_subtype,
		  { "Subtype", "pgm.poll.subtype", FT_UINT16, BASE_HEX,
		    VALS(poll_subtype_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_pathafi,
		  { "Path NLA AFI", "pgm.poll.pathafi", FT_UINT16, BASE_DEC,
		    VALS(afn_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_res,
		  { "Reserved", "pgm.poll.res", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_path,
		  { "Path NLA", "pgm.poll.path.ipv4", FT_IPv4, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_path6,
		  { "Path NLA", "pgm.poll.path.ipv6", FT_IPv6, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_backoff_ivl,
		  { "Back-off Interval", "pgm.poll.backoff_ivl", FT_UINT32, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_rand_str,
		  { "Random String", "pgm.poll.rand_str", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_poll_matching_bmask,
		  { "Matching Bitmask", "pgm.poll.matching_bmask", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_polr_sqn,
		  { "Sequence Number", "pgm.polr.sqn", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_polr_round,
		  { "Round", "pgm.polr.round", FT_UINT16, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_polr_res,
		  { "Reserved", "pgm.polr.res", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_ack_sqn,
		  { "Maximum Received Sequence Number", "pgm.ack.maxsqn", FT_UINT32,
		    BASE_HEX, NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_ack_bitmap,
		  { "Packet Bitmap", "pgm.ack.bitmap", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_type,
		  { "Type", "pgm.opts.type", FT_UINT8, BASE_HEX,
		    VALS(opt_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_len,
		  { "Length", "pgm.opts.len", FT_UINT8, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_tlen,
		  { "Total Length", "pgm.opts.tlen", FT_UINT16, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_genopt_end,
		  { "Option end", "pgm.genopts.end", FT_BOOLEAN, 8,
		    TFS(&tfs_yes_no), 0x80, NULL, HFILL }},
		{ &hf_pgm_genopt_type,
		  { "Type", "pgm.genopts.type", FT_UINT8, BASE_HEX,
		    VALS(opt_vals), 0x7f, NULL, HFILL }},
		{ &hf_pgm_genopt_len,
		  { "Length", "pgm.genopts.len", FT_UINT8, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_genopt_opx,
		  { "Option Extensibility Bits", "pgm.genopts.opx", FT_UINT8, BASE_HEX,
		    VALS(opx_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_parity_prm_po,
		  { "Parity Parameters", "pgm.opts.parity_prm.op", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_parity_prm_prmtgsz,
		  { "Transmission Group Size", "pgm.opts.parity_prm.prm_grp",
		    FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_join_res,
		  { "Reserved", "pgm.opts.join.res", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_join_minjoin,
		  { "Minimum Sequence Number", "pgm.opts.join.min_join",
		    FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_parity_grp_res,
		  { "Reserved", "pgm.opts.parity_prm.op", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_parity_grp_prmgrp,
		  { "Transmission Group Size", "pgm.opts.parity_prm.prm_grp",
		    FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_res,
		  { "Reserved", "pgm.opts.nak.op", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_list,
		  { "List", "pgm.opts.nak.list", FT_BYTES, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccdata_res,
		  { "Reserved", "pgm.opts.ccdata.res", FT_UINT8, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccdata_tsp,
		  { "Time Stamp", "pgm.opts.ccdata.tstamp", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccdata_afi,
		  { "Acker AFI", "pgm.opts.ccdata.afi", FT_UINT16, BASE_DEC,
		    VALS(afn_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccdata_res2,
		  { "Reserved", "pgm.opts.ccdata.res2", FT_UINT16, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccdata_acker,
		  { "Acker", "pgm.opts.ccdata.acker.ipv4", FT_IPv4, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccdata_acker6,
		  { "Acker", "pgm.opts.ccdata.acker.ipv6", FT_IPv6, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccfeedbk_res,
		  { "Reserved", "pgm.opts.ccdata.res", FT_UINT8, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccfeedbk_tsp,
		  { "Time Stamp", "pgm.opts.ccdata.tstamp", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccfeedbk_afi,
		  { "Acker AFI", "pgm.opts.ccdata.afi", FT_UINT16, BASE_DEC,
		    VALS(afn_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccfeedbk_lossrate,
		  { "Loss Rate", "pgm.opts.ccdata.lossrate", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccfeedbk_acker,
		  { "Acker", "pgm.opts.ccdata.acker.ipv4", FT_IPv4, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_ccfeedbk_acker6,
		  { "Acker", "pgm.opts.ccdata.acker.ipv6", FT_IPv6, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_bo_ivl_res,
		  { "Reserved", "pgm.opts.nak_bo_ivl.res", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_bo_ivl_bo_ivl,
		  { "Back-off Interval", "pgm.opts.nak_bo_ivl.bo_ivl", FT_UINT32, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_bo_ivl_bo_ivl_sqn,
		  { "Back-off Interval Sequence Number", "pgm.opts.nak_bo_ivl.bo_ivl_sqn", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_bo_rng_res,
		  { "Reserved", "pgm.opts.nak_bo_rng.res", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_bo_rng_min_bo_ivl,
		  { "Min Back-off Interval", "pgm.opts.nak_bo_rng.min_bo_ivl", FT_UINT32, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_nak_bo_rng_max_bo_ivl,
		  { "Max Back-off Interval", "pgm.opts.nak_bo_rng.max_bo_ivl", FT_UINT32, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_redirect_res,
		  { "Reserved", "pgm.opts.redirect.res", FT_UINT8, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_redirect_afi,
		  { "DLR AFI", "pgm.opts.redirect.afi", FT_UINT16, BASE_DEC,
		    VALS(afn_vals), 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_redirect_res2,
		  { "Reserved", "pgm.opts.redirect.res2", FT_UINT16, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_redirect_dlr,
		  { "DLR", "pgm.opts.redirect.dlr.ipv4", FT_IPv4, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_redirect_dlr6,
		  { "DLR", "pgm.opts.redirect.dlr.ipv6", FT_IPv6, BASE_NONE,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_fragment_res,
		  { "Reserved", "pgm.opts.fragment.res", FT_UINT8, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_fragment_first_sqn,
		  { "First Sequence Number", "pgm.opts.fragment.first_sqn", FT_UINT32, BASE_HEX,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_fragment_offset,
		  { "Fragment Offset", "pgm.opts.fragment.fragment_offset", FT_UINT32, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }},
		{ &hf_pgm_opt_fragment_total_length,
		  { "Total Length", "pgm.opts.fragment.total_length", FT_UINT32, BASE_DEC,
		    NULL, 0x0, NULL, HFILL }}
	};
	static gint *ett[] = {
		&ett_pgm,
		&ett_pgm_optbits,
		&ett_pgm_spm,
		&ett_pgm_data,
		&ett_pgm_nak,
		&ett_pgm_poll,
		&ett_pgm_polr,
		&ett_pgm_ack,
		&ett_pgm_opts,
		&ett_pgm_opts_join,
		&ett_pgm_opts_parityprm,
		&ett_pgm_opts_paritygrp,
		&ett_pgm_opts_naklist,
		&ett_pgm_opts_ccdata,
		&ett_pgm_opts_nak_bo_ivl,
		&ett_pgm_opts_nak_bo_rng,
		&ett_pgm_opts_redirect,
		&ett_pgm_opts_fragment
	};
	static ei_register_info ei[] = {
		{ &ei_pgm_opt_type, { "pgm.opts.type.invalid", PI_PROTOCOL, PI_WARN, "Invalid option", EXPFILL }},
		{ &ei_pgm_opt_tlen, { "pgm.opts.tlen.invalid", PI_PROTOCOL, PI_WARN, "Total Length invalid", EXPFILL }},
		{ &ei_pgm_genopt_len, { "pgm.genopts.len.invalid", PI_PROTOCOL, PI_WARN, "Option length invalid", EXPFILL }},
		{ &ei_address_format_invalid, { "pgm.address_format_invalid", PI_PROTOCOL, PI_WARN, "Can't handle this address format", EXPFILL }},
	};

	module_t *pgm_module;
	expert_module_t* expert_pgm;

	proto_pgm = proto_register_protocol("Pragmatic General Multicast",
					    "PGM", "pgm");

	proto_register_field_array(proto_pgm, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));
	expert_pgm = expert_register_protocol(proto_pgm);
	expert_register_field_array(expert_pgm, ei, array_length(ei));

	/* subdissector code */
	subdissector_table = register_dissector_table("pgm.port",
						      "PGM port", proto_pgm, FT_UINT16, BASE_DEC, DISSECTOR_TABLE_NOT_ALLOW_DUPLICATE);
	heur_subdissector_list = register_heur_dissector_list("pgm", proto_pgm);

	/*
	 * Register configuration preferences for UDP encapsulation
	 * (Note: Initially the ports are set to zero and the ports
	 *        are not registered so the dissecting of PGM
	 *        encapsulated in UDP packets is off by default;
	 *        dissector_add_for_decode_as is called so that pgm
	 *        is available for 'decode-as'
	 */
	pgm_module = prefs_register_protocol(proto_pgm, proto_reg_handoff_pgm);

	prefs_register_bool_preference(pgm_module, "check_checksum",
				       "Check the validity of the PGM checksum when possible",
				       "Whether to check the validity of the PGM checksum",
				       &pgm_check_checksum);

	prefs_register_uint_preference(pgm_module, "udp.encap_ucast_port",
				       "PGM Encap Unicast Port (standard is 3055)",
				       "PGM Encap is PGM packets encapsulated in UDP packets"
				       " (Note: This option is off, i.e. port is 0, by default)",
				       10, &udp_encap_ucast_port);

	prefs_register_uint_preference(pgm_module, "udp.encap_mcast_port",
				       "PGM Encap Multicast Port (standard is 3056)",
				       "PGM Encap is PGM packets encapsulated in UDP packets"
				       " (Note: This option is off, i.e. port is 0, by default)",
				       10, &udp_encap_mcast_port);

}

/* The registration hand-off routine */
/*
 * Set up PGM Encap dissecting, which is off by default for UDP
 */

void
proto_reg_handoff_pgm(void)
{
	static gboolean initialized = FALSE;
	static dissector_handle_t pgm_handle;
	static guint old_udp_encap_ucast_port;
	static guint old_udp_encap_mcast_port;

	if (! initialized) {
		pgm_handle = create_dissector_handle(dissect_pgm, proto_pgm);
		dissector_add_for_decode_as("udp.port", pgm_handle);
		dissector_add_uint("ip.proto", IP_PROTO_PGM, pgm_handle);
		initialized = TRUE;
	} else {
		if (old_udp_encap_ucast_port != 0) {
			dissector_delete_uint("udp.port", old_udp_encap_ucast_port, pgm_handle);
		}
		if (old_udp_encap_mcast_port != 0) {
			dissector_delete_uint("udp.port", old_udp_encap_mcast_port, pgm_handle);
		}
	}

	if (udp_encap_ucast_port != 0) {
		dissector_add_uint("udp.port", udp_encap_ucast_port, pgm_handle);
	}
	if (udp_encap_mcast_port != 0) {
		dissector_add_uint("udp.port", udp_encap_mcast_port, pgm_handle);
	}
	old_udp_encap_ucast_port = udp_encap_ucast_port;
	old_udp_encap_mcast_port = udp_encap_mcast_port;
}

/*
 * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 *
 * Local variables:
 * c-basic-offset: 8
 * tab-width: 8
 * indent-tabs-mode: t
 * End:
 *
 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 * :indentSize=8:tabSize=8:noTabs=false:
 */