From Stefano Pettini: RMT support for ALC and NORM.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@13029 f5534014-38df-0310-8fa8-9805f1628bb7

1 files changed, 276 insertions, 0 deletions

diff --git a/epan/dissectors/packet-rmt-alc.c b/epan/dissectors/packet-rmt-alc.c
new file mode 100644
index 0000000000..c882bd2a02
--- /dev/null
+++ b/epan/dissectors/packet-rmt-alc.c
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+/* packet-rmt-alc.c
+ * Reliable Multicast Transport (RMT)
+ * ALC Protocol Instantiation dissector
+ * Copyright 2005, Stefano Pettini <spettini@users.sourceforge.net>
+ *
+ * Asynchronous Layered Coding (ALC):
+ * ----------------------------------
+ *
+ * A massively scalable reliable content delivery protocol.
+ * Asynchronous Layered Coding combines the Layered Coding Transport
+ * (LCT) building block, a multiple rate congestion control building
+ * block and the Forward Error Correction (FEC) building block to
+ * provide congestion controlled reliable asynchronous delivery of
+ * content to an unlimited number of concurrent receivers from a single
+ * sender.
+ *
+ * References:
+ *     RFC 3450, Asynchronous Layered Coding protocol instantiation
+ *
+ * $Id$
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <glib.h>
+
+#include <epan/packet.h>
+#include <epan/prefs.h>
+
+#include "packet-rmt-alc.h"
+
+/* Initialize the protocol and registered fields */
+/* ============================================= */
+
+static int proto = -1;
+
+static struct _alc_hf hf;
+static struct _alc_ett ett;
+
+static gboolean preferences_initialized = FALSE;
+static struct _alc_prefs preferences;
+static struct _alc_prefs preferences_old;
+
+/* Preferences */
+/* =========== */
+
+/* Set/Reset preferences to default values */
+static void alc_prefs_set_default(struct _alc_prefs *prefs)
+{
+	prefs->use_default_udp_port = FALSE;
+	prefs->default_udp_port = 4001;
+	
+	lct_prefs_set_default(&prefs->lct);
+	fec_prefs_set_default(&prefs->fec);
+}
+
+/* Register preferences */
+static void alc_prefs_register(struct _alc_prefs *prefs, module_t *module)
+{
+	prefs_register_bool_preference(module,
+		"default.udp_port.enabled",
+		"Use default UDP port",
+		"Whether that payload of UDP packets with a specific destination port should be automatically dissected as ALC packets",
+		 &prefs->use_default_udp_port);
+
+ 	prefs_register_uint_preference(module,
+		"default.udp_port",
+		"Default UDP destination port",
+		"Specifies the UDP destination port for automatic dissection of ALC packets",
+		 10, &prefs->default_udp_port);
+		 
+	lct_prefs_register(&prefs->lct, module);
+	fec_prefs_register(&prefs->fec, module);
+}
+
+/* Save preferences to alc_prefs_old */
+static void alc_prefs_save(struct _alc_prefs *p, struct _alc_prefs *p_old)
+{
+	*p_old = *p;
+}
+
+/* Code to actually dissect the packets */
+/* ==================================== */
+
+static void dissect_alc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	/* Logical packet representation */
+	struct _alc alc;
+	
+	/* Offset for subpacket dissection */
+	guint offset;
+	
+	/* Set up structures needed to add the protocol subtree and manage it */
+	proto_item *ti;
+	proto_tree *alc_tree;
+	
+	/* Structures and variables initialization */
+	offset = 0;
+	memset(&alc, 0, sizeof(struct _alc));
+	
+	/* Update packet info */
+	pinfo->current_proto = "ALC";
+	
+	/* Make entries in Protocol column and Info column on summary display */
+	if (check_col(pinfo->cinfo, COL_PROTOCOL))
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, "ALC");
+	if (check_col(pinfo->cinfo, COL_INFO)) 
+		col_clear(pinfo->cinfo, COL_INFO);
+	
+	/* ALC header dissection */
+	/* --------------------- */
+		
+	alc.version = hi_nibble(tvb_get_guint8(tvb, offset));
+	
+	if (tree)
+	{
+		/* Create subtree for the ALC protocol */
+		ti = proto_tree_add_item(tree, proto, tvb, offset, -1, FALSE);
+		alc_tree = proto_item_add_subtree(ti, ett.main);
+		
+		/* Fill the ALC subtree */
+		proto_tree_add_uint(alc_tree, hf.version, tvb, offset, 1, alc.version);
+	
+	} else
+		alc_tree = NULL;
+		
+	/* This dissector supports only ALCv1 packets.
+	 * If alc.version > 1 print only version field and quit.
+	 */
+	if (alc.version == 1) {
+	
+		struct _lct_ptr l;
+		struct _fec_ptr f;
+		
+		l.lct = &alc.lct;
+		l.hf = &hf.lct;
+		l.ett = &ett.lct;
+		l.prefs = &preferences.lct;
+		
+		f.fec = &alc.fec;
+		f.hf = &hf.fec;
+		f.ett = &ett.fec;
+		f.prefs = &preferences.fec;
+		
+		/* LCT header dissection */
+		/* --------------------- */
+			
+		lct_dissector(l, f, tvb, alc_tree, &offset);
+		
+		/* FEC header dissection */
+		/* --------------------- */
+		
+		/* Only if it's present and if LCT dissector has determined FEC Encoding ID
+		 * FEC dissector should be called with fec->encoding_id* and fec->instance_id* filled
+		 */
+		if (alc.fec.encoding_id_present && tvb_length(tvb) > offset)
+			fec_dissector(f, tvb, alc_tree, &offset);
+		
+		/* Add the Payload item */
+		if (tvb_length(tvb) > offset)
+			proto_tree_add_none_format(alc_tree, hf.payload, tvb, offset, -1, "Payload (%u bytes)", tvb_length(tvb) - offset);
+		
+		/* Complete entry in Info column on summary display */
+		/* ------------------------------------------------ */
+		
+		if (check_col(pinfo->cinfo, COL_INFO))
+		{
+			lct_info_column(&alc.lct, pinfo);
+			fec_info_column(&alc.fec, pinfo);
+		}
+		
+		/* Free g_allocated memory */
+		lct_dissector_free(&alc.lct);
+		fec_dissector_free(&alc.fec);
+	
+	} else {
+
+		if (tree)
+			proto_tree_add_text(alc_tree, tvb, 0, -1, "Sorry, this dissector supports ALC version 1 only");
+		
+		/* Complete entry in Info column on summary display */
+		if (check_col(pinfo->cinfo, COL_INFO))
+			col_add_fstr(pinfo->cinfo, COL_INFO, "Version: %u (not supported)", alc.version);
+	}
+}
+
+void proto_reg_handoff_alc(void)
+{
+	static dissector_handle_t handle;
+
+	if (!preferences_initialized)
+	{
+		preferences_initialized = TRUE;		
+		handle = create_dissector_handle(dissect_alc, proto);
+		dissector_add_handle("udp.port", handle);
+		
+	} else {
+		
+		if (preferences_old.use_default_udp_port)
+			dissector_delete("udp.port", preferences_old.default_udp_port, handle);
+	}
+
+	if (preferences.use_default_udp_port)
+		dissector_add("udp.port", preferences.default_udp_port, handle);
+		
+	alc_prefs_save(&preferences, &preferences_old);
+}
+
+void proto_register_alc(void)
+{                 
+	/* Setup ALC header fields */
+	static hf_register_info hf_ptr[] = {
+		
+		{ &hf.version,
+			{ "Version", "alc.version", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }},
+		
+		LCT_FIELD_ARRAY(hf.lct, "alc"),
+		FEC_FIELD_ARRAY(hf.fec, "alc"),
+
+		{ &hf.payload,
+			{ "Payload", "alc.payload", FT_NONE, BASE_NONE, NULL, 0x0, "", HFILL }}
+	};
+
+	/* Setup protocol subtree array */
+	static gint *ett_ptr[] = {
+		&ett.main,
+		
+		LCT_SUBTREE_ARRAY(ett.lct),
+		FEC_SUBTREE_ARRAY(ett.fec)
+	};
+
+	module_t *module;
+	
+	/* Clear hf and ett fields */
+	memset(&hf, 0xff, sizeof(struct _alc_hf));
+	memset(&ett, 0xff, sizeof(struct _alc_ett));
+	
+	/* Register the protocol name and description */
+	proto = proto_register_protocol("Asynchronous Layered Coding", "ALC", "alc");
+
+	/* Register the header fields and subtrees used */
+	proto_register_field_array(proto, hf_ptr, array_length(hf_ptr));
+	proto_register_subtree_array(ett_ptr, array_length(ett_ptr));
+	
+	/* Reset preferences */
+	alc_prefs_set_default(&preferences);
+	alc_prefs_save(&preferences, &preferences_old);
+	
+	/* Register preferences */
+	module = prefs_register_protocol(proto, proto_reg_handoff_alc);
+	alc_prefs_register(&preferences, module);	
+}