#define LOG_MODULE PacketLogModuleEthLayer

#include "EthLayer.h"

#include "IPv4Layer.h"

#include "IPv6Layer.h"

#include "PayloadLayer.h"

#include "ArpLayer.h"

#include "VlanLayer.h"

#include "PPPoELayer.h"

#include "MplsLayer.h"

#include "WakeOnLanLayer.h"

#include "EndianPortable.h"

#include <string.h>

namespace pcpp

{

EthLayer::EthLayer(const MacAddress& sourceMac, const MacAddress& destMac, uint16_t etherType) : Layer()

{

  const size_t headerLen = sizeof(ether_header);

  m_DataLen = headerLen;

  m_Data = new uint8_t[headerLen];

  memset(m_Data, 0, headerLen);

  ether_header* ethHdr = (ether_header*)m_Data;

  destMac.copyTo(ethHdr->dstMac);

  sourceMac.copyTo(ethHdr->srcMac);

  ethHdr->etherType = htobe16(etherType);

  m_Protocol = Ethernet;

}

void EthLayer::parseNextLayer()

{

  if (m_DataLen <= sizeof(ether_header))

    return;

  ether_header* hdr = getEthHeader();

  uint8_t* payload = m_Data + sizeof(ether_header);

  size_t payloadLen = m_DataLen - sizeof(ether_header);

  switch (be16toh(hdr->etherType))

  {

  case PCPP_ETHERTYPE_IP:

    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_ETHERTYPE_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;

  case PCPP_ETHERTYPE_ARP:

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

    break;

  case PCPP_ETHERTYPE_VLAN:

  case PCPP_ETHERTYPE_IEEE_802_1AD:

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

    break;

  case PCPP_ETHERTYPE_PPPOES:

    m_NextLayer = PPPoESessionLayer::isDataValid(payload, payloadLen)

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

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

    break;

  case PCPP_ETHERTYPE_PPPOED:

    m_NextLayer = PPPoEDiscoveryLayer::isDataValid(payload, payloadLen)

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

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

    break;

  case PCPP_ETHERTYPE_MPLS:

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

    break;

  case PCPP_ETHERTYPE_WAKE_ON_LAN:

    m_NextLayer = WakeOnLanLayer::isDataValid(payload, payloadLen)

      ? static_cast<Layer*>(new WakeOnLanLayer(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);

  }

}

void EthLayer::computeCalculateFields()

{

  if (m_NextLayer == NULL)

    return;

  switch (m_NextLayer->getProtocol())

  {

  case IPv4:

    getEthHeader()->etherType = htobe16(PCPP_ETHERTYPE_IP);

    break;

  case IPv6:

    getEthHeader()->etherType = htobe16(PCPP_ETHERTYPE_IPV6);

    break;

  case ARP:

    getEthHeader()->etherType = htobe16(PCPP_ETHERTYPE_ARP);

    break;

  case VLAN:

    getEthHeader()->etherType = htobe16(PCPP_ETHERTYPE_VLAN);

    break;

  default:

    return;

  }

}

std::string EthLayer::toString() const

{

  return "Ethernet II Layer, Src: " + getSourceMac().toString() + ", Dst: " + getDestMac().toString();

}

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

{

  if (dataLen >= sizeof(ether_header))

  {

    /**

     * Ethertypes: These are 16-bit identifiers appearing as the initial

     * two octets after the MAC destination and source (or after a

     * tag) which, when considered as an unsigned integer, are equal

     * to or larger than 0x0600.

     *

     * From: https://tools.ietf.org/html/rfc5342#section-2.3.2.1

     * More: IEEE Std 802.3 Clause 3.2.6

     */

    return be16toh(*(uint16_t*)(data + 12)) >= (uint16_t)0x0600;

  }

  else

  {

    return false;

  }

}

} // namespace pcpp