/*
 * ssdp.c
 *
 * Copyright (C) 2009-2011 by ipoque GmbH
 * Copyright (C) 2011-18 - 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_SSDP

#include "ndpi_api.h"

#define SSDP_MIN_LEN        19

#define SSDP_MSEARCH        "M-SEARCH * HTTP/1.1"
#define SSDP_MSEARCH_LEN    (sizeof(SSDP_MSEARCH) - 1)
#define SSDP_NOTIFY         "NOTIFY * HTTP/1.1"
#define SSDP_NOTIFY_LEN     (sizeof(SSDP_NOTIFY) - 1)
#define SSDP_OK             "HTTP/1.1 200 OK"
#define SSDP_OK_LEN         (sizeof(SSDP_OK) - 1)

static void ndpi_int_ssdp_add_connection(struct ndpi_detection_module_struct
        *ndpi_struct, struct ndpi_flow_struct *flow)
{
    ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_SSDP);
}

/* this detection also works asymmetrically */
void ndpi_search_ssdp(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
{
    struct ndpi_packet_struct *packet = &flow->packet;

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

    if (packet->udp != NULL) {

        if (packet->payload_packet_len >= SSDP_MIN_LEN) {
            if ((memcmp(packet->payload, SSDP_MSEARCH, SSDP_MSEARCH_LEN) == 0)
                    || memcmp(packet->payload, SSDP_NOTIFY, SSDP_NOTIFY_LEN) == 0) {

                NDPI_LOG_INFO(ndpi_struct, "found ssdp\n");
                ndpi_int_ssdp_add_connection(ndpi_struct, flow);
                return;
            }

            if(memcmp(packet->payload, SSDP_OK, SSDP_OK_LEN) == 0) {
                NDPI_LOG_INFO(ndpi_struct, "found ssdp\n");
                ndpi_int_ssdp_add_connection(ndpi_struct, flow);
                return;
            }
        }
    }

    NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
}

void init_ssdp_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
{
    ndpi_set_bitmask_protocol_detection("SSDP", ndpi_struct, detection_bitmask, *id,
            NDPI_PROTOCOL_SSDP,
            ndpi_search_ssdp,
            NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_UDP_WITH_PAYLOAD,
            SAVE_DETECTION_BITMASK_AS_UNKNOWN,
            ADD_TO_DETECTION_BITMASK);

    *id += 1;
}
