#define LOG_MODULE PacketLogModuleNflogLayer

#include "NflogLayer.h"

#include "IPv4Layer.h"

#include "IPv6Layer.h"

#include "PayloadLayer.h"

#include "GeneralUtils.h"

#include "EndianPortable.h"

#include <string.h>

namespace pcpp

{

  /** IPv4 protocol */

  #define PCPP_WS_NFPROTO_IPV4    2

  /** IPv6 protocol */

  #define PCPP_WS_NFPROTO_IPV6    10

uint8_t NflogLayer::getFamily()

{

  return getNflogHeader()->addressFamily;

}

uint8_t NflogLayer::getVersion()

{

  return getNflogHeader()->version;

}

uint16_t NflogLayer::getResourceId()

{

  return be16toh(getNflogHeader()->resourceId);

}

NflogTlv NflogLayer::getTlvByType(NflogTlvType type) const

{

  NflogTlv tlv = m_TlvReader.getTLVRecord(

    static_cast<uint32_t> (type),

    getTlvsBasePtr(),

    m_DataLen - sizeof(nflog_header));

  return tlv;

}

void NflogLayer::parseNextLayer()

{

  if (m_DataLen <= sizeof(nflog_header))

    return;

  auto payloadInfo = getTlvByType(NflogTlvType::NFULA_PAYLOAD);

  if (payloadInfo.isNull())

  {

    return;

  }

  uint8_t* payload = payloadInfo.getValue();

  size_t payloadLen = payloadInfo.getTotalSize() - sizeof(uint16_t) * 2;

  uint8_t family = getFamily();

  switch (family)

  {

  case PCPP_WS_NFPROTO_IPV4:

    m_NextLayer = IPv4Layer::isDataValid(payload, payloadLen)

      ? static_cast<Layer*>(new IPv4Layer(payload, payloadLen, this, m_Packet))

      : static_cast<Layer*>(new PayloadLayer(payload, payloadLen, this, m_Packet));

    break;

  case PCPP_WS_NFPROTO_IPV6:

    m_NextLayer = IPv6Layer::isDataValid(payload, payloadLen)

      ? static_cast<Layer*>(new IPv6Layer(payload, payloadLen, this, m_Packet))

      : static_cast<Layer*>(new PayloadLayer(payload, payloadLen, this, m_Packet));

    break;

  default:

    m_NextLayer = new PayloadLayer(payload, payloadLen, this, m_Packet);

  }

}

size_t NflogLayer::getHeaderLen() const

{

  size_t headerLen = sizeof(nflog_header);

  NflogTlv currentTLV =  m_TlvReader.getFirstTLVRecord(

    getTlvsBasePtr(),

    m_DataLen - sizeof(nflog_header));

  while (!currentTLV.isNull() && currentTLV.getType() != static_cast<uint16_t> (NflogTlvType::NFULA_PAYLOAD))

  {

    headerLen += currentTLV.getTotalSize();

    currentTLV = m_TlvReader.getNextTLVRecord(currentTLV, getTlvsBasePtr(), m_DataLen - sizeof(nflog_header));

  }

  if (!currentTLV.isNull() && currentTLV.getType() == static_cast<uint16_t> (NflogTlvType::NFULA_PAYLOAD))

  {

    // for the length and type of the payload TLV

    headerLen += 2 * sizeof (uint16_t);

  }

  // nflog_header has not a form of TLV and contains 3 fields (family, resource_id, version)

  return headerLen;

}

std::string NflogLayer::toString() const

{

  return "Linux Netfilter NFLOG";

}

bool NflogLayer::isDataValid(const uint8_t* data, size_t dataLen)

{

  return data && dataLen >= sizeof(nflog_header);

}

} // namespace pcpp