/*

 * ubntac2.c

 *

 * Copyright (C) 2015 Thomas Fjellstrom

 *

 * 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_UBNTAC2

#include "ndpi_api.h"

#include "ndpi_private.h"

static void ndpi_int_ubntac2_add_connection(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)

{

  ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_UBNTAC2, NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);

}

static void ndpi_search_ubntac2(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)

{

  struct ndpi_packet_struct *packet = &ndpi_struct->packet;

  u_int8_t tlv_type;

  u_int16_t tlv_length, version_len;

  int off;

  NDPI_LOG_DBG(ndpi_struct, "search ubntac2\n");

  if(packet->payload_packet_len >= 4 &&

     (packet->udp->source == htons(10001) || packet->udp->dest == htons(10001)) &&

     (ntohs(get_u_int16_t(packet->payload, 0)) == 0x0206 ||

      ntohs(get_u_int16_t(packet->payload, 0)) == 0x0100 /* discovery request/reply */) &&

     (4 + ntohs(*(u_int16_t *)&packet->payload[2]) == packet->payload_packet_len)) {

    NDPI_LOG_INFO(ndpi_struct, "UBNT AirControl 2 request\n");

    ndpi_int_ubntac2_add_connection(ndpi_struct, flow);

    /* Parse TLV list: 1 byte type + 2 byte length + (optional) data */

    off = 4;

    while (off + 3 < packet->payload_packet_len) {

      tlv_type = packet->payload[off];

      tlv_length = ntohs(*(u_int16_t *)&packet->payload[off + 1]);

      NDPI_LOG_DBG2(ndpi_struct, "0x%x Len %d\n", tlv_type, tlv_length);

      if(tlv_type == 0x03 && off + 3 + tlv_length < packet->payload_packet_len) {

  version_len = ndpi_min(sizeof(flow->protos.ubntac2.version) - 1, tlv_length);

  memcpy(flow->protos.ubntac2.version, (const char *)&packet->payload[off + 3], version_len);

  flow->protos.ubntac2.version[version_len] = '\0';

      }

      off += 3 + tlv_length;

    }

    return;

  }

  NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);

}

void init_ubntac2_dissector(struct ndpi_detection_module_struct *ndpi_struct)

{

  register_dissector("UBNTAC2", ndpi_struct,

                     ndpi_search_ubntac2,

                     NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_UDP_WITH_PAYLOAD,

                     1, NDPI_PROTOCOL_UBNTAC2);

}