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#ifndef PACKETPP_VLAN_LAYER
#define PACKETPP_VLAN_LAYER
#include "Layer.h"
#include "EthLayer.h"
/// @file
/**
* \namespace pcpp
* \brief The main namespace for the PcapPlusPlus lib
*/
namespace pcpp
{
/**
* @struct vlan_header
* Represents a VLAN header
*/
#pragma pack(push, 1)
struct vlan_header
{
/**
@verbatim
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Prio |C| VLAN ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
@endverbatim
*/
uint16_t vlan;
/** Ethernet type for next layer */
uint16_t etherType;
};
#pragma pack(pop)
/**
* @class VlanLayer
* Represents a VLAN tunnel layer
*/
class VlanLayer : public Layer
{
public:
/** A constructor that creates the layer from an existing packet raw data
* @param[in] data A pointer to the raw data
* @param[in] dataLen Size of the data in bytes
* @param[in] prevLayer A pointer to the previous layer
* @param[in] packet A pointer to the Packet instance where layer will be stored in
*/
VlanLayer(uint8_t* data, size_t dataLen, Layer* prevLayer, Packet* packet) : Layer(data, dataLen, prevLayer, packet) { m_Protocol = VLAN; }
/**
* A constructor that allocates a new VLAN header
* @param[in] vlanID VLAN ID
* @param[in] cfi CFI value
* @param[in] priority Priority value
* @param[in] etherType Protocol EtherType of the next layer. It's an optional parameter, a value of 0 will be set if not provided
*/
VlanLayer(const uint16_t vlanID, bool cfi, uint8_t priority, uint16_t etherType = 0);
~VlanLayer() {}
/**
* Get a pointer to the VLAN header. Notice this points directly to the data, so every change will change the actual packet data
* @return A pointer to the vlan_header
*/
vlan_header* getVlanHeader() const { return (vlan_header*)m_Data; }
/**
* Get the VLAN ID value. This method differs from vlan_header#vlanID because vlan_header#vlanID is 12 bits long in a 16 bit field.
* This methods extracts only the 12 bit relevant for the VLAN ID
* @return VLAN ID value
* @todo Verify it works in big endian machines as well
*/
uint16_t getVlanID() const;
/**
* @return The CFI bit value
* @todo Verify it works in big endian machines as well
*/
uint8_t getCFI() const;
/**
* @return The priority value
* @todo Verify it works in big endian machines as well
*/
uint8_t getPriority() const;
/**
* Set VLAN ID. This method differs from setting vlan_header#vlanID because vlan_header#vlanID is 12 bits long in a 16 bit field.
* This methods sets only the 12 bit relevant for the VLAN ID
* @param[in] id The VLAN ID to set
* @todo Verify it works in big endian machines as well
*/
void setVlanID(uint16_t id);
/**
* Set CFI bit
* @param[in] cfi The CFI bit to set
* @todo Verify it works in big endian machines as well
*/
void setCFI(bool cfi);
/**
* Set priority value
* @param[in] priority The priority value to set
* @todo Verify it works in big endian machines as well
*/
void setPriority(uint8_t priority);
// implement abstract methods
/**
* Currently identifies the following next layers: IPv4Layer, IPv6Layer, ArpLayer, VlanLayer, MplsLayer. Otherwise sets PayloadLayer
*/
void parseNextLayer();
/**
* @return Size of vlan_header
*/
size_t getHeaderLen() const { return sizeof(vlan_header); }
/**
* Calculate the EtherType for known protocols: IPv4, IPv6, ARP, VLAN
*/
void computeCalculateFields();
std::string toString() const;
OsiModelLayer getOsiModelLayer() const { return OsiModelDataLinkLayer; }
};
} // namespace pcpp
#endif /* PACKETPP_VLAN_LAYER */