/*
 * genshin_impact.c
 *
 * Copyright (C) 2012-22 - ntop.org
 *
 * This module 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.
 *
 * This module 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.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "ndpi_protocol_ids.h"

#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_GENSHIN_IMPACT

#include "ndpi_api.h"


static void ndpi_int_genshin_impact_add_connection(
                struct ndpi_detection_module_struct *ndpi_struct,
                struct ndpi_flow_struct *flow)
{
  ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_GENSHIN_IMPACT, NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);
}

static void ndpi_search_genshin_impact(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 genshin-impact\n");

  if (packet->udp != NULL)
  {
    if (flow->packet_counter == 1 && packet->payload_packet_len >= 20 &&
        ntohl(*(u_int32_t*)&packet->payload[0]) == 0x000000FF &&
        ntohl(*(u_int32_t*)&packet->payload[4]) == 0x00000000 &&
        ntohl(*(u_int32_t*)&packet->payload[12]) == 0x499602D2 &&
        ntohl(*(u_int32_t*)&packet->payload[16]) == 0xFFFFFFFF)
    {
      ndpi_int_genshin_impact_add_connection(ndpi_struct, flow);
      return;
    }
  }

  NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
}


/* ***************************************************************** */

void init_genshin_impact_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id,
                                   NDPI_PROTOCOL_BITMASK *detection_bitmask)
{
  ndpi_set_bitmask_protocol_detection("Genshin Impact",
                                      ndpi_struct, detection_bitmask, *id,
                                      NDPI_PROTOCOL_GENSHIN_IMPACT,
                                      ndpi_search_genshin_impact,
                                      NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_UDP_WITH_PAYLOAD,
                                      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
                                      ADD_TO_DETECTION_BITMASK);

  *id += 1;
}