MRDISC support, from Ronnie Sahlberg.

svn path=/trunk/; revision=3614

1 files changed, 320 insertions, 0 deletions

diff --git a/packet-mrdisc.c b/packet-mrdisc.c
new file mode 100644
index 0000000000..6a4456daaa
--- /dev/null
+++ b/packet-mrdisc.c
@@ -0,0 +1,320 @@
+/* packet-mrdisc.c   2001 Ronnie Sahlberg <rsahlber@bigpond.net.au>
+ * Routines for IGMP/MRDISC packet disassembly
+ *
+ * $Id: packet-mrdisc.c,v 1.1 2001/06/27 20:19:19 guy Exp $
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@ethereal.com>
+ * Copyright 1998 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+/*
+
+
+			MRDISC
+	code			
+
+	0x24		x	
+	0x25		x
+	0x26		x
+
+	MRDISC : IGMP Multicast Router DISCovery
+	Defined in draft-ietf-idmr-igmp-mrdisc-06.txt
+	TTL==1 and IP.DST==224.0.0.2 for all packets.
+*/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <glib.h>
+
+#include "packet.h"
+#include "in_cksum.h"
+#include "packet-mrdisc.h"
+
+
+static int proto_mrdisc = -1;
+static int hf_checksum = -1;
+static int hf_checksum_bad = -1;
+static int hf_type = -1;
+static int hf_advint = -1;
+static int hf_numopts = -1;
+static int hf_options = -1;
+static int hf_option = -1;
+static int hf_option_len = -1;
+static int hf_qi = -1;
+static int hf_rv = -1;
+static int hf_option_bytes = -1;
+
+static int ett_mrdisc = -1;
+static int ett_options = -1;
+
+#define MRDISC_MRA	0x24
+#define MRDISC_MRS	0x25
+#define MRDISC_MRT	0x26
+static const value_string mrdisc_types[] = {
+	{MRDISC_MRA,	"Multicast Router Advertisement"},
+	{MRDISC_MRS,	"Multicast Router Solicitation"},
+	{MRDISC_MRT,	"Multicast Router Termination"},
+	{0,					NULL}
+};
+
+#define MRDISC_QI	0x01
+#define MRDISC_RV	0x02
+static const value_string mrdisc_options[] = {
+	{MRDISC_QI,	"Query Interval"},
+	{MRDISC_RV,	"Robustness Variable"},
+	{0,					NULL}
+};
+
+
+static void mrdisc_checksum(proto_tree *tree,tvbuff_t *tvb, int len)
+{
+	guint16 cksum,hdrcksum;
+	vec_t cksum_vec[1];
+
+	cksum_vec[0].ptr = tvb_get_ptr(tvb, 0, len);
+	cksum_vec[0].len = len;
+
+	hdrcksum = tvb_get_ntohs(tvb, 2);
+	cksum = in_cksum(&cksum_vec[0],1);
+
+	if (cksum==0) {
+		proto_tree_add_uint_format(tree, hf_checksum, tvb, 2, 2, hdrcksum, "Header checksum: 0x%04x (correct)", hdrcksum);
+	} else {
+		proto_tree_add_item_hidden(tree, hf_checksum_bad, tvb, 2, 2, TRUE);
+		proto_tree_add_uint_format(tree, hf_checksum, tvb, 2, 2, hdrcksum, "Header checksum: 0x%04x (incorrect, should be 0x%04x)", hdrcksum,in_cksum_shouldbe(hdrcksum,cksum));
+	}
+
+	return;
+}
+
+
+static int
+dissect_mrdisc_mra(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
+{
+	guint16 num;
+
+	/* Advertising Interval */
+	proto_tree_add_uint(parent_tree, hf_advint, tvb,
+		offset, 1, tvb_get_guint8(tvb, offset));
+	offset += 1;
+
+	/* checksum */
+	mrdisc_checksum(parent_tree, tvb, tvb_length_remaining(tvb, 0));
+	offset += 2;
+
+	/* skip unused bytes */
+	offset += 2;
+
+	/* number of options */
+	num = tvb_get_ntohs(tvb, offset);
+	proto_tree_add_uint(parent_tree, hf_numopts, tvb,
+		offset, 2, num);
+	offset += 2;
+
+	/* process any options */
+	while (num--) {
+		proto_tree *tree;
+		proto_item *item;
+		guint8 type,len;
+		int old_offset = offset;
+
+		item = proto_tree_add_item(parent_tree, hf_options, 
+			tvb, offset, 0, FALSE);
+		tree = proto_item_add_subtree(item, ett_options);
+
+		type = tvb_get_guint8(tvb, offset);
+		proto_tree_add_uint(tree, hf_option, tvb, offset, 1, type);
+		offset += 1;
+
+		len = tvb_get_guint8(tvb, offset);
+		proto_tree_add_uint(tree, hf_option_len, tvb, offset, 1, len);
+		offset += 1;
+
+		switch (type) {
+		case MRDISC_QI:
+			if (item) {
+				proto_item_set_text(item,"Option: %s == %d",
+					val_to_str(type, mrdisc_options, "unknown %x"),
+					tvb_get_ntohs(tvb, offset));
+			}
+
+			proto_tree_add_uint(tree, hf_qi, tvb, offset, len,
+				tvb_get_ntohs(tvb, offset));
+			offset += len;
+			break;
+		case MRDISC_RV:
+			if (item) {
+				proto_item_set_text(item,"Option: %s == %d",
+					val_to_str(type, mrdisc_options, "unknown %x"),
+					tvb_get_ntohs(tvb, offset));
+			}
+
+			proto_tree_add_uint(tree, hf_rv, tvb, offset, len,
+				tvb_get_ntohs(tvb, offset));
+			offset += len;
+			break;
+		default:
+			if (item) {
+				proto_item_set_text(item,"Option: unknown");
+			}
+
+			proto_tree_add_bytes(tree, hf_option_bytes,
+				tvb, offset, len, tvb_get_ptr(tvb, offset, len));
+			offset += len;
+		}
+		if (item) {
+			proto_item_set_len(item, offset-old_offset);
+		}
+	}
+	
+	return offset;
+}
+
+
+static int
+dissect_mrdisc_mrst(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
+{
+	/* skip reserved byte */
+	offset += 1;
+
+	/* checksum */
+	mrdisc_checksum(parent_tree, tvb, tvb_length_remaining(tvb, 0));
+	offset += 2;
+
+	return offset;
+}
+
+
+/* This function is only called from the IGMP dissector */
+int
+dissect_mrdisc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
+{
+	proto_tree *tree;
+	proto_item *item;
+	guint8 type;
+
+	if (!proto_is_protocol_enabled(proto_mrdisc)) {
+		/* we are not enabled, skip entire packet to be nice
+		   to the igmp layer. (so clicking on IGMP will display the data)
+		 */
+		return offset+tvb_length_remaining(tvb, offset);
+	}
+
+	item = proto_tree_add_item(parent_tree, proto_mrdisc, tvb, offset, 0, FALSE);
+	tree = proto_item_add_subtree(item, ett_mrdisc);
+
+
+	if (check_col(pinfo->fd, COL_PROTOCOL)) {
+		col_set_str(pinfo->fd, COL_PROTOCOL, "MRDISC");
+	}
+	if (check_col(pinfo->fd, COL_INFO)) {
+		col_clear(pinfo->fd, COL_INFO);
+	}
+
+
+	type = tvb_get_guint8(tvb, offset);
+	if (check_col(pinfo->fd, COL_INFO)) {
+		col_add_fstr(pinfo->fd, COL_INFO,
+			"%s",val_to_str(type, mrdisc_types, 
+				"Unknown Type:0x%02x"));
+	}
+
+	/* type of command */
+	proto_tree_add_uint(tree, hf_type, tvb, offset, 1, type);
+	offset += 1;
+
+	switch (type) {
+	case MRDISC_MRA:
+		offset = dissect_mrdisc_mra(tvb, pinfo, tree, offset);
+		break;
+	case MRDISC_MRS:
+	case MRDISC_MRT:
+		/* MRS and MRT packets looks the same */
+		offset = dissect_mrdisc_mrst(tvb, pinfo, tree, offset);
+		break;
+	}
+	return offset;
+}
+
+
+void
+proto_register_mrdisc(void)
+{
+	static hf_register_info hf[] = {
+		{ &hf_type,
+			{ "Type", "mrdisc.type", FT_UINT8, BASE_HEX,
+			  VALS(mrdisc_types), 0, "MRDISC Packet Type", HFILL }},
+
+		{ &hf_checksum,
+			{ "Checksum", "mrdisc.checksum", FT_UINT16, BASE_HEX,
+			  NULL, 0, "MRDISC Checksum", HFILL }},
+
+		{ &hf_checksum_bad,
+			{ "Bad Checksum", "mrdisc.checksum_bad", FT_BOOLEAN, BASE_NONE,
+			  NULL, 0, "Bad MRDISC Checksum", HFILL }},
+
+		{ &hf_advint,
+			{ "Advertising Interval", "mrdisc.adv_int", FT_UINT8, BASE_DEC,
+		  	  NULL, 0, "MRDISC Advertising Interval in seconds", HFILL }},
+
+		{ &hf_numopts,
+			{ "Number Of Options", "mrdisc.num_opts", FT_UINT16, BASE_DEC,
+		  	  NULL, 0, "MRDISC Number Of Options", HFILL }},
+
+		{ &hf_options,
+			{ "Options", "mrdisc.options", FT_NONE, BASE_NONE,
+			  NULL, 0, "MRDISC Options", HFILL }},
+
+		{ &hf_option,
+			{ "Option", "mrdisc.option", FT_UINT8, BASE_DEC,
+			  VALS(mrdisc_options), 0, "MRDISC Option Type", HFILL }},
+
+		{ &hf_option_len,
+			{ "Length", "mrdisc.opt_len", FT_UINT8, BASE_DEC,
+			  NULL, 0, "MRDISC Option Length", HFILL }},
+
+		{ &hf_qi,
+			{ "Query Interval", "mrdisc.query_int", FT_UINT16, BASE_DEC,
+		  	  NULL, 0, "MRDISC Query Interval", HFILL }},
+
+		{ &hf_rv,
+			{ "Robustness Variable", "mrdisc.rob_var", FT_UINT16, BASE_DEC,
+		  	  NULL, 0, "MRDISC Robustness Variable", HFILL }},
+
+		{ &hf_option_bytes,
+			{ "Data", "mrdisc.option_data", FT_BYTES, BASE_NONE,
+		  	  NULL, 0, "MRDISC Unknown Option Data", HFILL }},
+
+	};
+	static gint *ett[] = {
+		&ett_mrdisc,
+		&ett_options,
+	};
+
+	proto_mrdisc = proto_register_protocol("Multicast Router DISCovery protocol",
+	    "MRDISC", "mrdisc");
+	proto_register_field_array(proto_mrdisc, hf, array_length(hf));
+	proto_register_subtree_array(ett, array_length(ett));
+}