From Mohammad Ebrahim Mohammadi Panah via bug 2954:

I've developed a Wireshark dissector for Paltalk messenger protocol.

svn path=/trunk/; revision=28434

1 files changed, 133 insertions, 0 deletions

diff --git a/epan/dissectors/packet-paltalk.c b/epan/dissectors/packet-paltalk.c
new file mode 100644
index 0000000000..28dfbda251
--- /dev/null
+++ b/epan/dissectors/packet-paltalk.c
@@ -0,0 +1,133 @@
+/* packet-paltalk.c
+ * Routines for Paltalk dissection
+ * Copyright 2005, Tim Hentenaar < tim at hentenaar dot com >
+ * Copyright 2008, Mohammad Ebrahim Mohammadi Panah < mebrahim at gmail dot com >
+ *
+ * $Id$
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <gmodule.h>
+#include <epan/packet.h>
+#include <epan/prefs.h>
+
+#include "packet-tcp.h"
+
+#define PALTALK_SERVERS_ADDRESS 0x00006ac7U /* 199.106.0.0 */
+#define PALTALK_SERVERS_NETMASK 0x0000feffU /* /15 */
+
+#define PALTALK_HEADER_LENGTH 6
+
+/* forward reference */
+void proto_register_paltalk();
+void proto_reg_handoff_paltalk();
+static gboolean dissect_paltalk(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
+static guint dissect_paltalk_get_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset);
+static void dissect_paltalk_desegmented(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
+
+static int proto_paltalk = -1;
+static int hf_paltalk_pdu_type = -1;
+static int hf_paltalk_version = -1;
+static int hf_paltalk_length = -1;
+static int hf_paltalk_content = -1;
+static gint ett_paltalk = -1;
+
+static hf_register_info hf[] = {
+	{ &hf_paltalk_pdu_type, { "Packet Type", "paltalk.type", FT_UINT16, BASE_HEX, NULL, 0x00, "", HFILL }},
+	{ &hf_paltalk_version,  { "Protocol Version", "paltalk.version", FT_INT16, BASE_DEC, NULL, 0x00, "", HFILL }},
+	{ &hf_paltalk_length,   { "Payload Length", "paltalk.length", FT_INT16, BASE_DEC, NULL, 0x00, "", HFILL }},
+	{ &hf_paltalk_content,  { "Payload Content", "paltalk.content", FT_BYTES, BASE_NONE, NULL, 0x00, "", HFILL }}
+};
+
+/* Setup protocol subtree array */
+static gint *ett[] = { &ett_paltalk };
+
+void
+proto_register_paltalk(void)
+{
+	module_t *paltalk_module;
+
+	if (proto_paltalk == -1)
+		proto_paltalk = proto_register_protocol("Paltalk Messenger Protocol"
+				, "Paltalk", "paltalk");
+	paltalk_module = prefs_register_protocol(proto_paltalk, proto_reg_handoff_paltalk);
+}
+
+void
+proto_reg_handoff_paltalk(void)
+{
+	static int initialized = 0;
+
+	if (!initialized) {
+		heur_dissector_add("tcp", dissect_paltalk, proto_paltalk);
+		proto_register_field_array(proto_paltalk, hf, array_length(hf));
+		proto_register_subtree_array(ett, array_length(ett));
+		initialized = 1;
+	}
+}
+
+static gboolean
+dissect_paltalk(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	/* Detect if this TCP session is a Paltalk one */
+	/* TODO: Optimize detection logic if possible */
+	if (pinfo->net_src.type != AT_IPv4 || pinfo->net_dst.type != AT_IPv4
+			|| pinfo->net_src.len != 4 || pinfo->net_dst.len != 4
+			|| !pinfo->net_src.data || !pinfo->net_dst.data
+			|| (((*(guint32*) pinfo->net_src.data) & PALTALK_SERVERS_NETMASK) != PALTALK_SERVERS_ADDRESS
+			 && ((*(guint32*) pinfo->net_dst.data) & PALTALK_SERVERS_NETMASK) != PALTALK_SERVERS_ADDRESS))
+		return FALSE;
+	/* Dissect result of desegmented TCP data */
+	tcp_dissect_pdus(tvb, pinfo, tree, TRUE, PALTALK_HEADER_LENGTH
+			, dissect_paltalk_get_len, dissect_paltalk_desegmented);
+	return TRUE;
+}
+
+static guint
+dissect_paltalk_get_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset)
+{
+	return tvb_get_ntohs(tvb, offset + 4) + PALTALK_HEADER_LENGTH;
+}
+
+static void
+dissect_paltalk_desegmented(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	proto_item *ti = NULL;
+	proto_tree *pt_tree = NULL;
+
+	if (check_col(pinfo->cinfo, COL_PROTOCOL))
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, "Paltalk");
+	if (check_col(pinfo->cinfo, COL_INFO))
+		col_clear(pinfo->cinfo, COL_INFO);
+
+	if (tree)		/* we are being asked for details */
+	{
+		ti = proto_tree_add_item(tree, proto_paltalk, tvb, 0, -1, FALSE);
+		pt_tree = proto_item_add_subtree(ti, ett_paltalk);
+		proto_tree_add_item(pt_tree, hf_paltalk_pdu_type, tvb, 0, 2, FALSE);
+		proto_tree_add_item(pt_tree, hf_paltalk_version, tvb, 2, 2, FALSE);
+		proto_tree_add_item(pt_tree, hf_paltalk_length, tvb, 4, 2, FALSE);
+		proto_tree_add_item(pt_tree, hf_paltalk_content, tvb, 6, tvb_get_ntohs(tvb, 4), FALSE);
+	}
+}