/*

 * mining.c

 *

 * Copyright (C) 2018-22 - 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_MINING

#include "ndpi_api.h"

#include "ndpi_private.h"

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

u_int64_t mining_make_lru_cache_key(struct ndpi_flow_struct *flow) {

  u_int64_t key;

  /* network byte order */

  if(flow->is_ipv6)

    key = (ndpi_quick_hash64((const char *)flow->c_address.v6, 16) << 32) | (ndpi_quick_hash64((const char *)flow->s_address.v6, 16) & 0xFFFFFFFF);

  else

    key = ((u_int64_t)flow->c_address.v4 << 32) | flow->s_address.v4;

  return key;

}

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

static void cacheMiningHostTwins(struct ndpi_detection_module_struct *ndpi_struct,

         struct ndpi_flow_struct *flow) {

  if(ndpi_struct->mining_cache)

    ndpi_lru_add_to_cache(ndpi_struct->mining_cache, mining_make_lru_cache_key(flow), NDPI_PROTOCOL_MINING, ndpi_get_current_time(flow));

}

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

static void ndpi_search_mining(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 MINING\n");

  /* Quick test: we are looking for only Json format */

  if(packet->payload[0] != '{') {

    NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);

    return;

  }

  /* STRATUMv1 */

  if(ndpi_strnstr((const char *)packet->payload, "\"mining.subscribe\"", packet->payload_packet_len) ||

     ndpi_strnstr((const char *)packet->payload, "\"mining.configure\"", packet->payload_packet_len)) {

    /* Try matching some zcash domains like "eu1-zcash.flypool.org" */

    if(ndpi_strnstr((const char *)packet->payload, "zcash", packet->payload_packet_len))

      ndpi_snprintf(flow->protos.mining.currency, sizeof(flow->protos.mining.currency), "%s", "ZCash");

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

    cacheMiningHostTwins(ndpi_struct, flow);

    return;

  }

  /* Xmr-stak-cpu is a ZCash/Monero CPU miner */

  if(ndpi_strnstr((const char *)packet->payload, "\"agent\":\"xmr-stak-cpu", packet->payload_packet_len)) {

    ndpi_snprintf(flow->protos.mining.currency, sizeof(flow->protos.mining.currency), "%s", "ZCash/Monero");

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

    cacheMiningHostTwins(ndpi_struct, flow);

    return;

  }

  if(ndpi_strnstr((const char *)packet->payload, "\"method\": \"eth_submitLogin", packet->payload_packet_len)) {

    ndpi_snprintf(flow->protos.mining.currency, sizeof(flow->protos.mining.currency), "%s", "Ethereum");

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

    cacheMiningHostTwins(ndpi_struct, flow);

    return;

  }

  NDPI_EXCLUDE_DISSECTOR(ndpi_struct, flow);

}

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

void init_mining_dissector(struct ndpi_detection_module_struct *ndpi_struct)

{

  register_dissector("Mining", ndpi_struct,

                     ndpi_search_mining,

                     NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,

                      1, NDPI_PROTOCOL_MINING);

}