#include <DhcpLayer.h>

Inheritance diagram for pcpp::DhcpLayer:

Public Member Functions
	DhcpLayer (uint8_t data, size_t dataLen, Layer prevLayer, Packet *packet)

	DhcpLayer (DhcpMessageType msgType, const MacAddress &clientMacAddr)

	DhcpLayer ()
	A constructor that creates the layer from scratch with clean data.

	~DhcpLayer () override=default
	A destructor for this layer.

dhcp_header *	getDhcpHeader () const

BootpOpCodes	getOpCode () const

IPv4Address	getClientIpAddress () const

void	setClientIpAddress (const IPv4Address &addr)

IPv4Address	getServerIpAddress () const

void	setServerIpAddress (const IPv4Address &addr)

IPv4Address	getYourIpAddress () const

void	setYourIpAddress (const IPv4Address &addr)

IPv4Address	getGatewayIpAddress () const

void	setGatewayIpAddress (const IPv4Address &addr)

MacAddress	getClientHardwareAddress () const

void	setClientHardwareAddress (const MacAddress &addr)

DhcpMessageType	getMessageType () const

bool	setMessageType (DhcpMessageType msgType)

DhcpOption	getFirstOptionData () const

DhcpOption	getNextOptionData (DhcpOption dhcpOption) const

DhcpOption	getOptionData (DhcpOptionTypes option) const

size_t	getOptionsCount () const

DhcpOption	addOption (const DhcpOptionBuilder &optionBuilder)

DhcpOption	addOptionAfter (const DhcpOptionBuilder &optionBuilder, DhcpOptionTypes prevOption)

bool	removeOption (DhcpOptionTypes optionType)

bool	removeAllOptions ()

void	parseNextLayer () override
	Does nothing for this layer (DhcpLayer is always last)

size_t	getHeaderLen () const override

void	computeCalculateFields () override

std::string	toString () const override

OsiModelLayer	getOsiModelLayer () const override

Public Member Functions inherited from pcpp::Layer
	~Layer () override

Layer *	getNextLayer () const

Layer *	getPrevLayer () const

ProtocolType	getProtocol () const

bool	isMemberOfProtocolFamily (ProtocolTypeFamily protocolTypeFamily) const

uint8_t *	getData () const

size_t	getDataLen () const

uint8_t *	getLayerPayload () const

size_t	getLayerPayloadSize () const

bool	isAllocatedToPacket () const

void	copyData (uint8_t *toArr) const

uint8_t *	getDataPtr (size_t offset=0) const override

Static Public Member Functions
static bool	isDhcpPorts (uint16_t portSrc, uint16_t portDst)

Additional Inherited Members
Protected Member Functions inherited from pcpp::Layer
template<typename T , typename... Args>
Layer *	constructNextLayer (uint8_t data, size_t dataLen, Packet packet, Args &&... extraArgs)

template<typename T , typename TFallback , typename... Args>
Layer *	tryConstructNextLayerWithFallback (uint8_t data, size_t dataLen, Packet packet, Args &&... extraArgs)

Static Protected Member Functions inherited from pcpp::Layer
template<typename T >
static bool	canReinterpretAs (const uint8_t *data, size_t dataLen)
	Check if the data is large enough to reinterpret as a type. More...

Detailed Description

Represents a DHCP (Dynamic Host Configuration Protocol) protocol layer

Constructor & Destructor Documentation

◆ DhcpLayer() [1/2]

pcpp::DhcpLayer::DhcpLayer	(	uint8_t *	data,
		size_t	dataLen,
		Layer *	prevLayer,
		Packet *	packet
	)

A constructor that creates the layer from an existing packet raw data

Parameters

[in]	data	A pointer to the raw data
[in]	dataLen	Size of the data in bytes
[in]	prevLayer	A pointer to the previous layer
[in]	packet	A pointer to the Packet instance where layer will be stored in

◆ DhcpLayer() [2/2]

pcpp::DhcpLayer::DhcpLayer	(	DhcpMessageType	msgType,
		const MacAddress &	clientMacAddr
	)

A constructor that creates the layer from scratch. Adds a DHCPOPT_DHCP_MESSAGE_TYPE and a DHCPOPT_END options

Parameters

[in]	msgType	A DHCP message type to be set
[in]	clientMacAddr	A client MAC address to set in dhcp_header::clientHardwareAddress field

Member Function Documentation

◆ addOption()

DhcpOption pcpp::DhcpLayer::addOption ( const DhcpOptionBuilder & optionBuilder )

Add a new DHCP option at the end of the layer

Parameters

[in] optionBuilder A DhcpOptionBuilder object that contains the requested DHCP option data to add

Returns: A DhcpOption object containing the newly added DHCP option data or logical null (DhcpOption::isNull() == true) if addition failed

◆ addOptionAfter()

DhcpOption pcpp::DhcpLayer::addOptionAfter	(	const DhcpOptionBuilder &	optionBuilder,
		DhcpOptionTypes	prevOption
	)

Add a new DHCP option after an existing one

Parameters

[in]	optionBuilder	A DhcpOptionBuilder object that contains the requested DHCP option data to add
[in]	prevOption	The DHCP option type which the newly added option will come after

Returns: A DhcpOption object containing the newly added DHCP option data or logical null (DhcpOption::isNull() == true) if addition failed

◆ computeCalculateFields()

void pcpp::DhcpLayer::computeCalculateFields ( )

overridevirtual

Calculate the following fields:

dhcp_header::magicNumber = DHCP magic number (0x63538263)
dhcp_header::opCode = DHCP_BOOTREQUEST for message types: DHCP_DISCOVER, DHCP_REQUEST, DHCP_DECLINE, DHCP_RELEASE, DHCP_INFORM, DHCP_UNKNOWN_MSG_TYPE DHCP_BOOTREPLY for message types: DHCP_OFFER, DHCP_ACK, DHCP_NAK
dhcp_header::hardwareType = 1 (Ethernet)
dhcp_header::hardwareAddressLength = 6 (MAC address length)

Implements pcpp::Layer.

◆ getClientHardwareAddress()

MacAddress pcpp::DhcpLayer::getClientHardwareAddress ( ) const

Returns: The client MAC address as extracted from dhcp_header::clientHardwareAddress, assuming dhcp_header::hardwareType is 1 (Ethernet) and dhcp_header::hardwareAddressLength is 6 (MAC address length). Otherwise returns MacAddress::Zero

◆ getClientIpAddress()

IPv4Address pcpp::DhcpLayer::getClientIpAddress ( ) const

inline

Returns: The client IPv4 address (as extracted from dhcp_header::clientIpAddress converted to IPv4Address object)

◆ getDhcpHeader()

dhcp_header* pcpp::DhcpLayer::getDhcpHeader ( ) const

inline

Get a pointer to the DHCP header. Notice this points directly to the data, so every change will change the actual packet data

Returns: A pointer to the dhcp_header

◆ getFirstOptionData()

DhcpOption pcpp::DhcpLayer::getFirstOptionData ( ) const

Returns: The first DHCP option in the packet. If there are no DHCP options the returned value will contain a logical null (DhcpOption::isNull() == true)

◆ getGatewayIpAddress()

IPv4Address pcpp::DhcpLayer::getGatewayIpAddress ( ) const

inline

Returns: Gateway IPv4 address (as extracted from dhcp_header::gatewayIpAddress converted to IPv4Address object)

◆ getHeaderLen()

size_t pcpp::DhcpLayer::getHeaderLen ( ) const

inlineoverridevirtual

Returns: The size of dhcp_header + size of options

Implements pcpp::Layer.

◆ getMessageType()

DhcpMessageType pcpp::DhcpLayer::getMessageType ( ) const

Returns: DHCP message type as extracted from DHCPOPT_DHCP_MESSAGE_TYPE option. If this option doesn't exist the value of DHCP_UNKNOWN_MSG_TYPE is returned

◆ getNextOptionData()

DhcpOption pcpp::DhcpLayer::getNextOptionData ( DhcpOption dhcpOption ) const

Get the DHCP option that comes after a given option. If the given option was the last one, the returned value will contain a logical null (DhcpOption::isNull() == true)

Parameters

[in] dhcpOption A given DHCP option

Returns: A DhcpOption object containing the option data that comes next, or logical null if the given DHCP option: (1) was the last one; (2) contains a logical null or (3) doesn't belong to this packet

◆ getOpCode()

BootpOpCodes pcpp::DhcpLayer::getOpCode ( ) const

inline

Returns: The BootP opcode of this message

◆ getOptionData()

DhcpOption pcpp::DhcpLayer::getOptionData ( DhcpOptionTypes option ) const

Get a DHCP option by type

Parameters

[in] option DHCP option type

Returns: A DhcpOption object containing the first DHCP option data that matches this type, or logical null (DhcpOption::isNull() == true) if no such option found

◆ getOptionsCount()

size_t pcpp::DhcpLayer::getOptionsCount ( ) const

Returns: The number of DHCP options in this layer

◆ getOsiModelLayer()

OsiModelLayer pcpp::DhcpLayer::getOsiModelLayer ( ) const

inlineoverridevirtual

Returns: The OSI Model layer this protocol belongs to

Implements pcpp::Layer.

◆ getServerIpAddress()

IPv4Address pcpp::DhcpLayer::getServerIpAddress ( ) const

inline

Returns: The server IPv4 address (as extracted from dhcp_header::serverIpAddress converted to IPv4Address object)

◆ getYourIpAddress()

IPv4Address pcpp::DhcpLayer::getYourIpAddress ( ) const

inline

Returns: Your IPv4 address (as extracted from dhcp_header::yourIpAddress converted to IPv4Address object)

◆ isDhcpPorts()

bool pcpp::DhcpLayer::isDhcpPorts	(	uint16_t	portSrc,
		uint16_t	portDst
	)

inlinestatic

A static method that checks whether a pair of ports are considered DHCP ports

Parameters

[in]	portSrc	The source port number to check
[in]	portDst	The destination port number to check

Returns: True if these are DHCP port numbers, false otherwise

◆ removeAllOptions()

bool pcpp::DhcpLayer::removeAllOptions ( )

Remove all DHCP options in this layer

Returns: True if all DHCP options were successfully removed or false if removal failed for some reason

◆ removeOption()

bool pcpp::DhcpLayer::removeOption ( DhcpOptionTypes optionType )

Remove an existing DHCP option from the layer

Parameters

[in] optionType The DHCP option type to remove

Returns: True if DHCP option was successfully removed or false if type wasn't found or if removal failed

◆ setClientHardwareAddress()

void pcpp::DhcpLayer::setClientHardwareAddress ( const MacAddress & addr )

Set a MAC address into the first 6 bytes of dhcp_header::clientHardwareAddress. This method also sets dhcp_header::hardwareType to 1 (Ethernet) and dhcp_header::hardwareAddressLength to 6 (MAC address length)

Parameters

[in] addr The MAC address to set

◆ setClientIpAddress()

void pcpp::DhcpLayer::setClientIpAddress ( const IPv4Address & addr )

inline

Set the client IPv4 address in dhcp_header::clientIpAddress

Parameters

[in] addr The IPv4 address to set

◆ setGatewayIpAddress()

void pcpp::DhcpLayer::setGatewayIpAddress ( const IPv4Address & addr )

inline

Set the gateway IPv4 address in dhcp_header::gatewayIpAddress

Parameters

[in] addr The IPv4 address to set

◆ setMessageType()

bool pcpp::DhcpLayer::setMessageType ( DhcpMessageType msgType )

Set DHCP message type. This method searches for existing DHCPOPT_DHCP_MESSAGE_TYPE option. If found, it sets the requested message type as its value. If not, it creates a DHCPOPT_DHCP_MESSAGE_TYPE option and sets the requested message type as its value

Parameters

[in] msgType Message type to set

Returns: True if message type was set successfully or false if msgType is DHCP_UNKNOWN_MSG_TYPE or if failed to add DHCPOPT_DHCP_MESSAGE_TYPE option

◆ setServerIpAddress()

void pcpp::DhcpLayer::setServerIpAddress ( const IPv4Address & addr )

inline

Set the server IPv4 address in dhcp_header::serverIpAddress

Parameters

[in] addr The IPv4 address to set

◆ setYourIpAddress()

void pcpp::DhcpLayer::setYourIpAddress ( const IPv4Address & addr )

inline

Set your IPv4 address in dhcp_header::yourIpAddress

Parameters

[in] addr The IPv4 address to set

◆ toString()

std::string pcpp::DhcpLayer::toString ( ) const

overridevirtual

Returns: A string representation of the layer most important data (should look like the layer description in Wireshark)

Implements pcpp::Layer.

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ DhcpLayer() [1/2]

◆ DhcpLayer() [2/2]

Member Function Documentation

◆ addOption()

◆ addOptionAfter()

◆ computeCalculateFields()

◆ getClientHardwareAddress()

◆ getClientIpAddress()

◆ getDhcpHeader()

◆ getFirstOptionData()

◆ getGatewayIpAddress()

◆ getHeaderLen()

◆ getMessageType()

◆ getNextOptionData()

◆ getOpCode()

◆ getOptionData()

◆ getOptionsCount()

◆ getOsiModelLayer()

◆ getServerIpAddress()

◆ getYourIpAddress()

◆ isDhcpPorts()

◆ removeAllOptions()

◆ removeOption()

◆ setClientHardwareAddress()

◆ setClientIpAddress()

◆ setGatewayIpAddress()

◆ setMessageType()

◆ setServerIpAddress()

◆ setYourIpAddress()

◆ toString()