/*
 * crossfire.c
 *
 * Copyright (C) 2012-22 - ntop.org
 *
 * This file is part of nDPI, an open source deep packet inspection
 * library based on the OpenDPI and PACE technology by ipoque GmbH
 *
 * nDPI is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * nDPI 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with nDPI.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "ndpi_protocol_ids.h"

#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_CROSSFIRE

#include "ndpi_api.h"
#include "ndpi_private.h"


static void ndpi_int_crossfire_add_connection(struct ndpi_detection_module_struct *ndpi_struct, 
					      struct ndpi_flow_struct *flow)
{

  ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_CROSSFIRE, NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);
}

static void ndpi_search_crossfire_tcp_udp(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
{
	struct ndpi_packet_struct *packet = &ndpi_struct->packet;

	NDPI_LOG_DBG(ndpi_struct, "search crossfire\n");

	if (packet->udp != 0) {
		if (packet->payload_packet_len == 25
			&& get_u_int32_t(packet->payload, 0) == ntohl(0xc7d91999)
			&& get_u_int16_t(packet->payload, 4) == ntohs(0x0200)
			&& get_u_int16_t(packet->payload, 22) == ntohs(0x7d00)) {
		    NDPI_LOG_INFO(ndpi_struct, "found Crossfire: udp packet\n");
		    ndpi_int_crossfire_add_connection(ndpi_struct, flow);
		    return;
		}

	} else if (packet->tcp != 0) {

		if (packet->payload_packet_len > 4 && memcmp(packet->payload, "GET /", 5) == 0) {
			ndpi_parse_packet_line_info(ndpi_struct, flow);
			if (packet->parsed_lines == 8
				&& (packet->line[0].ptr != NULL && packet->line[0].len >= 30
					&& (memcmp(&packet->payload[5], "notice/login_big", 16) == 0
						|| memcmp(&packet->payload[5], "notice/login_small", 18) == 0))
				&& memcmp(&packet->payload[packet->line[0].len - 19], "/index.asp HTTP/1.", 18) == 0
				&& (packet->host_line.ptr != NULL && packet->host_line.len >= 13
					&& (memcmp(packet->host_line.ptr, "crossfire", 9) == 0
						|| memcmp(packet->host_line.ptr, "www.crossfire", 13) == 0))
				) {
			     NDPI_LOG_DBG(ndpi_struct, "found Crossfire: HTTP request\n");
			     ndpi_int_crossfire_add_connection(ndpi_struct, flow);
			     return;
			}
		}

	}

	NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
}


void init_crossfire_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id)
{
  ndpi_set_bitmask_protocol_detection("Crossfire", ndpi_struct, *id,
				      NDPI_PROTOCOL_CROSSFIRE,
				      ndpi_search_crossfire_tcp_udp,
				      NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_OR_UDP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
				      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
				      ADD_TO_DETECTION_BITMASK);
  *id += 1;
}