/* packet-mongo.c
 * Routines for Mongo Wire Protocol dissection
 * Copyright 2010, Alexis La Goutte <alexis.lagoutte at gmail dot com>
 *
 * $Id: packet-mongo.c 35224 2010-12-20 05:35:29Z guy $
 *
 * 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.
 */

/*
 * See Mongo Wire Protocol Specification
 * http://www.mongodb.org/display/DOCS/Mongo+Wire+Protocol
 * See also BSON Specification
 * http://bsonspec.org/#/specification
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <glib.h>

#include <epan/packet.h>
#include <epan/prefs.h>
#include "packet-tcp.h"

/* This is not IANA assigned nor registered */
#define TCP_PORT_MANGO 27017

#define OP_REPLY 	1
#define OP_MSG 		1000
#define OP_UPDATE 	2001
#define OP_INSERT 	2002
#define OP_RESERVED 	2003
#define OP_QUERY 	2004
#define OP_GET_MORE 	2005
#define OP_DELETE 	2006
#define OP_KILL_CURSORS 2007

/* ************************************************************************  */
/*                 		  OpCode		                     */
/* ************************************************************************  */
static const value_string opcode_vals[] = {
  { OP_REPLY, 	"Reply" },
  { OP_MSG, 	"Message" },
  { OP_UPDATE, 	"Update document" },
  { OP_INSERT, 	"Insert document" },
  { OP_RESERVED,"Reserved" },
  { OP_QUERY, 	"Query" },
  { OP_GET_MORE,"Get More" },
  { OP_DELETE, 	"Delete document" },
  { OP_KILL_CURSORS, "Kill Cursors" },
  { 0,     NULL }
};

void proto_reg_handoff_mongo(void);


static int proto_mongo = -1;
static int hf_mongo_message_length = -1;
static int hf_mongo_request_id = -1;
static int hf_mongo_response_to = -1;
static int hf_mongo_op_code = -1;
static int hf_mongo_fullcollectionname = -1;
static int hf_mongo_database_name = -1;
static int hf_mongo_collection_name = -1;
static int hf_mongo_reply_flags = -1;
static int hf_mongo_reply_flags_cursornotfound = -1;
static int hf_mongo_reply_flags_queryfailure = -1;
static int hf_mongo_reply_flags_sharedconfigstale = -1;
static int hf_mongo_reply_flags_awaitcapable = -1;
static int hf_mongo_cursor_id = -1;
static int hf_mongo_starting_from = -1;
static int hf_mongo_number_returned = -1;
static int hf_mongo_message = -1;
static int hf_mongo_zero = -1;
static int hf_mongo_update_flags = -1;
static int hf_mongo_update_flags_upsert = -1;
static int hf_mongo_update_flags_multiupdate = -1;
static int hf_mongo_selector = -1;
static int hf_mongo_update = -1;
static int hf_mongo_query_flags = -1;
static int hf_mongo_query_flags_tailablecursor = -1;
static int hf_mongo_query_flags_slaveok = -1;
static int hf_mongo_query_flags_oplogreplay = -1;
static int hf_mongo_query_flags_nocursortimeout = -1;
static int hf_mongo_query_flags_awaitdata = -1;
static int hf_mongo_query_flags_exhaust = -1;
static int hf_mongo_number_to_skip = -1;
static int hf_mongo_number_to_return = -1;
static int hf_mongo_query = -1;
static int hf_mongo_return_field_selector = -1;
static int hf_mongo_documents = -1;
static int hf_mongo_document_length = -1;
static int hf_mongo_delete_flags = -1;
static int hf_mongo_delete_flags_singleremove = -1;
static int hf_mongo_number_of_cursor_ids = -1;

static guint global_mongo_tcp_port = TCP_PORT_MANGO;

static dissector_handle_t data_handle;

static gint ett_mongo = -1;
static gint ett_mongo_doc = -1;
static gint ett_mongo_fcn = -1;
static gint ett_mongo_flags = -1;

static int
dissect_fullcollectionname(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
	gint32 fcn_length, dbn_length;
	proto_item *ti;
	proto_tree *fcn_tree;

	ti = proto_tree_add_item(tree, hf_mongo_fullcollectionname, tvb, offset, -1, ENC_NA);
	fcn_length = tvb_strsize(tvb, offset);

	/* If this doesn't find anything, we'll just throw an exception below */
	dbn_length = tvb_find_guint8(tvb, offset, fcn_length, '.') - offset;

	fcn_tree = proto_item_add_subtree(ti, ett_mongo_fcn);

	proto_tree_add_item(fcn_tree, hf_mongo_database_name, tvb, offset, dbn_length, ENC_NA);

	proto_tree_add_item(fcn_tree, hf_mongo_collection_name, tvb, offset + 1 + dbn_length, fcn_length - dbn_length - 2, ENC_NA);

	return fcn_length;
}

static int
dissect_bson_document(tvbuff_t *tvb, guint offset, proto_tree *tree, int hf_mongo_document)
{
	gint32 document_length;
	proto_item *ti;
	proto_tree *doc_tree;

	document_length = tvb_get_letohl(tvb, offset);
	/* TODO Implement BSON spec to correctly see BSON document type and not in Bytes format... */
	ti = proto_tree_add_item(tree, hf_mongo_document, tvb, offset+4, document_length-4, ENC_NA);
	doc_tree = proto_item_add_subtree(ti, ett_mongo_doc);

	proto_tree_add_item(doc_tree, hf_mongo_document_length, tvb, offset, 4, ENC_LITTLE_ENDIAN);

	return document_length;
}
static int
dissect_mongo_reply(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
	proto_item *ti;
	proto_tree *flags_tree;
	gint  i, number_returned;

	ti = proto_tree_add_item(tree, hf_mongo_reply_flags, tvb, offset, 4, ENC_NA);
	flags_tree = proto_item_add_subtree(ti, ett_mongo_flags);
	proto_tree_add_item(flags_tree, hf_mongo_reply_flags_cursornotfound, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_reply_flags_queryfailure, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_reply_flags_sharedconfigstale, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_reply_flags_awaitcapable, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	proto_tree_add_item(tree, hf_mongo_cursor_id, tvb, offset, 8, ENC_LITTLE_ENDIAN);
	offset += 8;

	proto_tree_add_item(tree, hf_mongo_starting_from, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	proto_tree_add_item(tree, hf_mongo_number_returned, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	number_returned = tvb_get_letohl(tvb, offset);
	offset += 4;

	for (i=1; i <= number_returned; i++)
	{
		offset += dissect_bson_document(tvb, offset, tree, hf_mongo_documents);
	}
	return offset;
}
static int
dissect_mongo_msg(tvbuff_t *tvb, guint offset, proto_tree *tree)
{

	proto_item *ti;

	ti = proto_tree_add_item(tree, hf_mongo_message, tvb, offset, -1, ENC_NA);
	offset += proto_item_get_len(ti);

	return offset;
}

static int
dissect_mongo_update(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
	proto_item *ti;
	proto_tree *flags_tree;

	proto_tree_add_item(tree, hf_mongo_zero, tvb, offset, 4, ENC_NA);
	offset += 4;

	offset += dissect_fullcollectionname(tvb, offset, tree);

	ti = proto_tree_add_item(tree, hf_mongo_update_flags, tvb, offset, 4, ENC_NA);
	flags_tree = proto_item_add_subtree(ti, ett_mongo_flags);
	proto_tree_add_item(flags_tree, hf_mongo_update_flags_upsert, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_update_flags_multiupdate, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	offset += dissect_bson_document(tvb, offset, tree, hf_mongo_selector);

	offset += dissect_bson_document(tvb, offset, tree, hf_mongo_update);

	return offset;
}

static int
dissect_mongo_insert(tvbuff_t *tvb, guint offset, proto_tree *tree)
{

	proto_tree_add_item(tree, hf_mongo_zero, tvb, offset, 4, ENC_NA);
	offset += 4;

	offset += dissect_fullcollectionname(tvb, offset, tree);

	while(offset < tvb_reported_length(tvb)) {
		offset += dissect_bson_document(tvb, offset, tree, hf_mongo_documents);
	}

	return offset;
}

static int
dissect_mongo_query(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
	proto_item *ti;
	proto_tree *flags_tree;

	ti = proto_tree_add_item(tree, hf_mongo_query_flags, tvb, offset, 4, ENC_NA);
	flags_tree = proto_item_add_subtree(ti, ett_mongo_flags);
	proto_tree_add_item(flags_tree, hf_mongo_query_flags_tailablecursor, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_query_flags_slaveok, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_query_flags_oplogreplay, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_query_flags_nocursortimeout, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_query_flags_awaitdata, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	proto_tree_add_item(flags_tree, hf_mongo_query_flags_exhaust, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	offset += dissect_fullcollectionname(tvb, offset, tree);

	proto_tree_add_item(tree, hf_mongo_number_to_skip, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	proto_tree_add_item(tree, hf_mongo_number_to_return, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset +=4;

	offset += dissect_bson_document(tvb, offset, tree, hf_mongo_query);

	while(offset < tvb_reported_length(tvb)) {
		offset += dissect_bson_document(tvb, offset, tree, hf_mongo_return_field_selector);
	}
	return offset;
}

static int
dissect_mongo_getmore(tvbuff_t *tvb, guint offset, proto_tree *tree)
{

	proto_tree_add_item(tree, hf_mongo_zero, tvb, offset, 4, ENC_NA);
	offset += 4;

	offset += dissect_fullcollectionname(tvb, offset, tree);

	proto_tree_add_item(tree, hf_mongo_number_to_return, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	proto_tree_add_item(tree, hf_mongo_cursor_id, tvb, offset, 8, ENC_LITTLE_ENDIAN);
	offset += 8;

	return offset;
}

static int
dissect_mongo_delete(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
	proto_item *ti;
	proto_tree *flags_tree;

	proto_tree_add_item(tree, hf_mongo_zero, tvb, offset, 4, ENC_NA);
	offset += 4;

	offset += dissect_fullcollectionname(tvb, offset, tree);

	ti = proto_tree_add_item(tree, hf_mongo_delete_flags, tvb, offset, 4, ENC_NA);
	flags_tree = proto_item_add_subtree(ti, ett_mongo_flags);
	proto_tree_add_item(flags_tree, hf_mongo_delete_flags_singleremove, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	offset += dissect_bson_document(tvb, offset, tree, hf_mongo_selector);

	return offset;
}

static int
dissect_mongo_kill_cursors(tvbuff_t *tvb, guint offset, proto_tree *tree)
{

	proto_tree_add_item(tree, hf_mongo_zero, tvb, offset, 4, ENC_NA);
	offset += 4;

	proto_tree_add_item(tree, hf_mongo_number_of_cursor_ids, tvb, offset, 4, ENC_LITTLE_ENDIAN);
	offset += 4;

	while(offset < tvb_reported_length(tvb)) {
		proto_tree_add_item(tree, hf_mongo_cursor_id, tvb, offset, 8, ENC_LITTLE_ENDIAN);
		offset +=8;
	}
	return offset;
}
static void
dissect_mongo_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{

	proto_item *ti;
	proto_tree *mongo_tree;
	guint offset = 0, opcode;
	tvbuff_t *next_tvb;

	col_set_str(pinfo->cinfo, COL_PROTOCOL, "MONGO");

	if (tree) {

		ti = proto_tree_add_item(tree, proto_mongo, tvb, 0, -1, ENC_NA);

		mongo_tree = proto_item_add_subtree(ti, ett_mongo);

		proto_tree_add_item(mongo_tree, hf_mongo_message_length, tvb, offset, 4, ENC_LITTLE_ENDIAN);
		offset += 4;

		proto_tree_add_item(mongo_tree, hf_mongo_request_id, tvb, offset, 4, ENC_LITTLE_ENDIAN);
		offset += 4;

		proto_tree_add_item(mongo_tree, hf_mongo_response_to, tvb, offset, 4, ENC_LITTLE_ENDIAN);
		offset += 4;

		proto_tree_add_item(mongo_tree, hf_mongo_op_code, tvb, offset, 4, ENC_LITTLE_ENDIAN);
		opcode = tvb_get_letohl(tvb, offset);
		offset += 4;

		if(opcode == 1)
		{
			col_set_str(pinfo->cinfo, COL_INFO, "Response :");
		}
		else
		{
			col_set_str(pinfo->cinfo, COL_INFO, "Request :");

		}
		col_append_fstr(pinfo->cinfo, COL_INFO, " %s", val_to_str(opcode, opcode_vals, "Unknown"));

		switch(opcode){
		case OP_REPLY:
			offset = dissect_mongo_reply(tvb, offset, mongo_tree);
		break;
		case OP_MSG:
			offset = dissect_mongo_msg(tvb, offset, mongo_tree);
		break;
		case OP_UPDATE:
			offset = dissect_mongo_update(tvb, offset, mongo_tree);
		break;
		case OP_INSERT:
			offset = dissect_mongo_insert(tvb, offset, mongo_tree);
		break;
		case OP_QUERY:
			offset = dissect_mongo_query(tvb, offset, mongo_tree);
		break;
		case OP_GET_MORE:
			offset = dissect_mongo_getmore(tvb, offset, mongo_tree);
		break;
		case OP_DELETE:
			offset = dissect_mongo_delete(tvb, offset, mongo_tree);
		break;
		case OP_KILL_CURSORS:
			offset = dissect_mongo_kill_cursors(tvb, offset, mongo_tree);
		break;
		default:
			next_tvb = tvb_new_subset(tvb, offset, -1, -1);
			call_dissector(data_handle,next_tvb, pinfo, tree);
		break;
		}

	}

}
static guint
get_mongo_pdu_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset)
{
	guint32 plen;

	/*
	* Get the length of the MONGO packet.
	*/
	plen = tvb_get_letohl(tvb, offset);

	return plen;
}

static void
dissect_mongo(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	tcp_dissect_pdus(tvb, pinfo, tree, 1, 4, get_mongo_pdu_len, dissect_mongo_pdu);
}

void
proto_register_mongo(void)
{
	module_t *mongo_module;

	static hf_register_info hf[] = {
		{ &hf_mongo_message_length,
			{ "Message Length",           "mongo.message_length",
			FT_INT32, BASE_DEC, NULL, 0x0,
			"Total message size (include this)", HFILL }
		},
		{ &hf_mongo_request_id,
			{ "Request ID",           "mongo.request_id",
			FT_UINT32, BASE_HEX_DEC, NULL, 0x0,
			"Identifier for this message", HFILL }
		},
		{ &hf_mongo_response_to,
			{ "Response To",           "mongo.response_to",
			FT_UINT32, BASE_HEX_DEC, NULL, 0x0,
			"RequestID from the original request", HFILL }
		},
		{ &hf_mongo_op_code,
			{ "OpCode",           "mongo.opcode",
			FT_INT32, BASE_DEC, VALS(opcode_vals), 0x0,
			"Type of request message", HFILL }
		},
		{ &hf_mongo_query_flags,
			{ "Query Flags",           "mongo.query.flags",
			FT_NONE, BASE_NONE, NULL, 0x0,
			"Bit vector of query options.", HFILL }
		},
		{ &hf_mongo_fullcollectionname,
			{ "fullCollectionName",           "mongo.full_collection_name",
			FT_STRINGZ, BASE_NONE, NULL, 0x0,
			"The full collection name is the concatenation of the database name with the collection name, using a dot for the concatenation", HFILL }
		},
		{ &hf_mongo_database_name,
			{ "Database Name",           "mongo.database_name",
			FT_STRING, BASE_NONE, NULL, 0x0,
			NULL, HFILL }
		},
		{ &hf_mongo_collection_name,
			{ "Collection Name",           "mongo.collection_name",
			FT_STRING, BASE_NONE, NULL, 0x0,
			NULL, HFILL }
		},
		{ &hf_mongo_reply_flags,
			{ "Reply Flags",           "mongo.reply.flags",
			FT_NONE, BASE_NONE, NULL, 0x0,
			"Bit vector of reply options.", HFILL }
		},
		{ &hf_mongo_reply_flags_cursornotfound,
			{ "Cursor Not Found",           "mongo.reply.flags.cursornotfound",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000001,
			"Set when getMore is called but the cursor id is not valid at the server", HFILL }
		},
		{ &hf_mongo_reply_flags_queryfailure,
			{ "Query Failure",           "mongo.reply.flags.queryfailure",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000002,
			"Set when query failed. Results consist of one document containing an $err field describing the failure.", HFILL }
		},
		{ &hf_mongo_reply_flags_sharedconfigstale,
			{ "Shared Config Stale",           "mongo.reply.flags.sharedconfigstale",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000004,
			NULL, HFILL }
		},
		{ &hf_mongo_reply_flags_awaitcapable,
			{ "Await Capable",           "mongo.reply.flags.awaitcapable",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000008,
			"Set when the server supports the AwaitData Query option", HFILL }
		},
		{ &hf_mongo_message,
			{ "Message",           "mongo.message",
			FT_STRINGZ, BASE_NONE, NULL, 0x0,
			"Message for the database", HFILL }
		},
		{ &hf_mongo_cursor_id,
			{ "Cursor ID",           "mongo.cursor_id",
			FT_INT64, BASE_DEC, NULL, 0x0,
			"Cursor id if client needs to do get more's", HFILL }
		},
		{ &hf_mongo_starting_from,
			{ "Starting From",           "mongo.starting_from",
			FT_INT32, BASE_DEC, NULL, 0x0,
			"Where in the cursor this reply is starting", HFILL }
		},
		{ &hf_mongo_number_returned,
			{ "Number Returned",           "mongo.number_returned",
			FT_INT32, BASE_DEC, NULL, 0x0,
			"Number of documents in the reply", HFILL }
		},
		{ &hf_mongo_documents,
			{ "Documents",           "mongo.documents",
			FT_BYTES, BASE_NONE, NULL, 0x0,
			NULL, HFILL }
		},
		{ &hf_mongo_document_length,
			{ "Document length",           "mongo.document.length",
			FT_INT32, BASE_DEC, NULL, 0x0,
			"Length of BSON Document", HFILL }
		},
		{ &hf_mongo_zero,
			{ "Zero",           "mongo.document.zero",
			FT_BYTES, BASE_NONE, NULL, 0x0,
			"Reserved (Must be is Zero)", HFILL }
		},
		{ &hf_mongo_update_flags,
			{ "Update Flags",           "mongo.update.flags",
			FT_NONE, BASE_NONE, NULL, 0x0,
			"Bit vector of update options.", HFILL }
		},
		{ &hf_mongo_update_flags_upsert,
			{ "Upsert",           "mongo.update.flags.upsert",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000001,
			"If set, the database will insert the supplied object into the collection if no matching document is found", HFILL }
		},
		{ &hf_mongo_update_flags_multiupdate,
			{ "Multi Update",           "mongo.update.flags.multiupdate",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000002,
			"If set, the database will update all matching objects in the collection. Otherwise only updates first matching doc.", HFILL }
		},
		{ &hf_mongo_selector,
			{ "Selector",           "mongo.selector",
			FT_BYTES, BASE_NONE, NULL, 0x0,
			"The query to select the document", HFILL }
		},
		{ &hf_mongo_update,
			{ "Update",           "mongo.update",
			FT_BYTES, BASE_NONE, NULL, 0x0,
			"Specification of the update to perform", HFILL }
		},
		{ &hf_mongo_query_flags_tailablecursor,
			{ "Tailable Cursor",           "mongo.query.flags.tailable_cursor",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000002,
			"Tailable means cursor is not closed when the last data is retrieved", HFILL }
		},
		{ &hf_mongo_query_flags_slaveok,
			{ "Slave OK",           "mongo.query.flags.slave_ok",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000004,
			"Allow query of replica slave", HFILL }
		},
		{ &hf_mongo_query_flags_oplogreplay,
			{ "Op Log Reply",           "mongo.query.flags.op_log_reply",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000008,
			"Internal replication use only", HFILL }
		},
		{ &hf_mongo_query_flags_nocursortimeout,
			{ "No Cursor Timeout",           "mongo.query.flags.no_cursor_timeout",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000010,
			"The server normally times out idle cursors after an inactivity period (10 minutes) to prevent excess memory use. Set this option to prevent that", HFILL }
		},
		{ &hf_mongo_query_flags_awaitdata,
			{ "AwaitData",           "mongo.query.flags.awaitdata",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000020,
			"If we are at the end of the data, block for a while rather than returning no data. After a timeout period, we do return as normal", HFILL }
		},
		{ &hf_mongo_query_flags_exhaust,
			{ "Exhaust",           "mongo.query.flags.exhaust",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000040,
			"Stream the data down full blast in multiple more packages, on the assumption that the client will fully read all data queried", HFILL }
		},
		{ &hf_mongo_number_to_skip,
			{ "Number To Skip",           "mongo.number_to_skip",
			FT_INT32, BASE_DEC, NULL, 0x0,
			"Number of documents in the skip", HFILL }
		},
		{ &hf_mongo_number_to_return,
			{ "Number to Return",           "mongo.number_to_return",
			FT_INT32, BASE_DEC, NULL, 0x0,
			"Number of documents in the return", HFILL }
		},
		{ &hf_mongo_query,
			{ "Query",           "mongo.query",
			FT_BYTES, BASE_NONE, NULL, 0x0,
			"Query BSON Document", HFILL }
		},
		{ &hf_mongo_return_field_selector,
			{ "Return Field Selector",           "mongo.return_field_selector",
			FT_BYTES, BASE_NONE, NULL, 0x0,
			"Return Field Selector BSON Document", HFILL }
		},
		{ &hf_mongo_delete_flags,
			{ "Delete Flags",           "mongo.delete.flags",
			FT_NONE, BASE_NONE, NULL, 0x0,
			"Bit vector of delete options.", HFILL }
		},
		{ &hf_mongo_delete_flags_singleremove,
			{ "Single Remove",           "mongo.delete.flags.singleremove",
			FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x00000001,
			"If set, the database will remove only the first matching document in the collection. Otherwise all matching documents will be removed", HFILL }
		},
		{ &hf_mongo_number_of_cursor_ids,
			{ "Number of Cursor IDS",           "mongo.number_to_cursor_ids",
			FT_INT32, BASE_DEC, NULL, 0x0,
			"Number of cursorIDs in message", HFILL }
		},
	};

	static gint *ett[] = {
		&ett_mongo,
		&ett_mongo_doc,
		&ett_mongo_fcn,
		&ett_mongo_flags
	};

	proto_mongo = proto_register_protocol("Mongo Wire Protocol", "MONGO", "mongo");

	proto_register_field_array(proto_mongo, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));

	mongo_module = prefs_register_protocol(proto_mongo,
	    proto_reg_handoff_mongo);

	prefs_register_uint_preference(mongo_module, "tcp.port", "MONGO TCP Port",
	     "MONGO TCP port if other than the default",
	     10, &global_mongo_tcp_port);
}


void
proto_reg_handoff_mongo(void)
{
	static gboolean initialized = FALSE;
        static dissector_handle_t mongo_handle;
        static int currentPort;

	if (!initialized) {

		mongo_handle = create_dissector_handle(dissect_mongo, proto_mongo);
		data_handle = find_dissector("data");
		initialized = TRUE;
	} else {


		dissector_delete_uint("tcp.port", currentPort, mongo_handle);
	}

	currentPort = global_mongo_tcp_port;

	dissector_add_uint("tcp.port", currentPort, mongo_handle);

}
