#include <GtpLayer.h>

Inheritance diagram for pcpp::GtpV1Layer:

Classes
class	GtpExtension

Public Member Functions
	GtpV1Layer (uint8_t data, size_t dataLen, Layer prevLayer, Packet *packet)

	GtpV1Layer (GtpV1MessageType messageType, uint32_t teid)

	GtpV1Layer (GtpV1MessageType messageType, uint32_t teid, bool setSeqNum, uint16_t seqNum, bool setNpduNum, uint8_t npduNum)

gtpv1_header *	getHeader () const

bool	getSequenceNumber (uint16_t &seqNumber) const

bool	setSequenceNumber (const uint16_t seqNumber)

bool	getNpduNumber (uint8_t &npduNum) const

bool	setNpduNumber (const uint8_t npduNum)

bool	getNextExtensionHeaderType (uint8_t &nextExtType) const

GtpExtension	getNextExtension () const

GtpExtension	addExtension (uint8_t extensionType, uint16_t extensionContent)

GtpV1MessageType	getMessageType () const

std::string	getMessageTypeAsString () const

bool	isGTPUMessage () const

bool	isGTPCMessage () const

void	parseNextLayer ()

size_t	getHeaderLen () const

void	computeCalculateFields ()

std::string	toString () const

OsiModelLayer	getOsiModelLayer () const

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

Layer *	getNextLayer () const

Layer *	getPrevLayer () const

ProtocolType	getProtocol () 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

Static Public Member Functions
static bool	isGTPv1 (const uint8_t *data, size_t dataSize)

static bool	isGTPv1Port (uint16_t port)

Detailed Description

A class representing the GTP v1 protocol.

Constructor & Destructor Documentation

◆ GtpV1Layer() [1/3]

pcpp::GtpV1Layer::GtpV1Layer	(	uint8_t *	data,
		size_t	dataLen,
		Layer *	prevLayer,
		Packet *	packet
	)

inline

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

◆ GtpV1Layer() [2/3]

pcpp::GtpV1Layer::GtpV1Layer	(	GtpV1MessageType	messageType,
		uint32_t	teid
	)

A constructor that creates a new GTPv1 layer and sets the message type and the TEID value

Parameters

[in]	messageType	The GTPv1 message type to be set in the newly created layer
[in]	teid	The TEID value to be set in the newly created layer

◆ GtpV1Layer() [3/3]

pcpp::GtpV1Layer::GtpV1Layer	(	GtpV1MessageType	messageType,
		uint32_t	teid,
		bool	setSeqNum,
		uint16_t	seqNum,
		bool	setNpduNum,
		uint8_t	npduNum
	)

A constructor that creates a new GTPv1 layer and sets various parameters

Parameters

[in]	messageType	The GTPv1 message type to be set in the newly created layer
[in]	teid	The TEID value to be set in the newly created layer
[in]	setSeqNum	A flag indicating whether to set a sequence number. If set to "false" then the parameter "seqNum" will be ignored
[in]	seqNum	The sequence number to be set in the newly created later. If "setSeqNum" is set to false this parameter will be ignored
[in]	setNpduNum	A flag indicating whether to set the N-PDU number. If set to "false" then the parameter "npduNum" will be ignored
[in]	npduNum	The N-PDU number to be set in the newly created later. If "setNpduNum" is set to false this parameter will be ignored

Member Function Documentation

◆ addExtension()

GtpExtension pcpp::GtpV1Layer::addExtension	(	uint8_t	extensionType,
		uint16_t	extensionContent
	)

Add a GTPv1 header extension. It is assumed that the extension is 4 bytes in legnth and its content is 2 bytes in length. If you need a different content size please reach out to me. This method takes care of extending the layer to make room for the new extension and also sets the relevant flags and fields

Parameters

[in]	extensionType	The type of the new extension
[in]	extensionContent	A 2-byte long content

Returns: An object representing the newly added extension. If there was an error adding the extension a null object will be returned (meaning GtpExtension::isNull() will return "true") and a corresponding error message will be written to log

◆ computeCalculateFields()

void pcpp::GtpV1Layer::computeCalculateFields ( )

virtual

Calculate the following fields:

gtpv1_header::messageLength

Implements pcpp::Layer.

◆ getHeader()

gtpv1_header* pcpp::GtpV1Layer::getHeader ( ) const

inline

Returns: The GTP v1 common header structure. Notice this points directly to the data, so every change will change the actual packet data

◆ getHeaderLen()

size_t pcpp::GtpV1Layer::getHeaderLen ( ) const

virtual

Returns: The size of the GTP header. For GTP-C packets the size is determined by the value of gtpv1_header::messageLength and for GTP-U the size only includes the GTP header itself (meaning the size of gtpv1_header plus the size of the optional fields such as sequence number, N-PDU or extensions if exist)

Implements pcpp::Layer.

◆ getMessageType()

GtpV1MessageType pcpp::GtpV1Layer::getMessageType ( ) const

Returns: The message type of this GTP packet

◆ getMessageTypeAsString()

std::string pcpp::GtpV1Layer::getMessageTypeAsString ( ) const

Returns: A string representation of the packet's message type

◆ getNextExtension()

GtpExtension pcpp::GtpV1Layer::getNextExtension ( ) const

Returns: An object that represents the next extension header, if exists in the message. If there are no extensions an empty object is returned, meaning an object which GtpExtension::isNull() returns "true"

◆ getNextExtensionHeaderType()

bool pcpp::GtpV1Layer::getNextExtensionHeaderType ( uint8_t & nextExtType ) const

Get the type of the next header extension if exists on the message (extensions are optional in GTP messages)

Parameters

[out] nextExtType Set with the next header extension type if exists in layer. Otherwise remains unchanged

Returns: True if the message contains header extensions, in which case nextExtType is set to the next header extension type. If there are no header extensions false is returned and nextExtType remains unchanged

◆ getNpduNumber()

bool pcpp::GtpV1Layer::getNpduNumber ( uint8_t & npduNum ) const

Get the N-PDU number if exists on the message (N-PDU number is an optional field in GTP messages)

Parameters

[out] npduNum Set with the N-PDU number value if exists in the layer. Otherwise remains unchanged

Returns: True if the N-PDU number field exists in layer, in which case npduNum is set with the value. Or false otherwise

◆ getOsiModelLayer()

OsiModelLayer pcpp::GtpV1Layer::getOsiModelLayer ( ) const

inlinevirtual

Returns: The OSI Model layer this protocol belongs to

Implements pcpp::Layer.

◆ getSequenceNumber()

bool pcpp::GtpV1Layer::getSequenceNumber ( uint16_t & seqNumber ) const

Get the sequence number if exists on the message (sequence number is an optional field in GTP messages)

Parameters

[out] seqNumber Set with the sequence number value if exists in the layer. Otherwise remains unchanged

Returns: True if the sequence number field exists in layer, in which case seqNumber is set with the value. Or false otherwise

◆ isGTPCMessage()

bool pcpp::GtpV1Layer::isGTPCMessage ( ) const

Returns: True if this is a GTP-C message, false otherwise

◆ isGTPUMessage()

bool pcpp::GtpV1Layer::isGTPUMessage ( ) const

Returns: True if this is a GTP-U message, false otherwise

◆ isGTPv1()

static bool pcpp::GtpV1Layer::isGTPv1	(	const uint8_t *	data,
		size_t	dataSize
	)

static

A static method that takes a byte array and detects whether it is a GTP v1 message

Parameters

[in]	data	A byte array
[in]	dataSize	The byte array size (in bytes)

Returns: True if the data is identified as GTP v1 message (GTP-C or GTP-U)

◆ isGTPv1Port()

static bool pcpp::GtpV1Layer::isGTPv1Port ( uint16_t port )

inlinestatic

A static method that checks whether the port is considered as GTPv1

Parameters

[in] port The port number to be checked

◆ parseNextLayer()

void pcpp::GtpV1Layer::parseNextLayer ( )

virtual

Identifies the following next layers for GTP-U packets: IPv4Layer, IPv6Layer. Otherwise sets PayloadLayer

Implements pcpp::Layer.

◆ setNpduNumber()

bool pcpp::GtpV1Layer::setNpduNumber ( const uint8_t npduNum )

Set an N-PDU number

Parameters

[in] npduNum The N-PDU number to set

Returns: True if the value was set successfully, false otherwise. In case of failure a corresponding error message will be written to log

◆ setSequenceNumber()

bool pcpp::GtpV1Layer::setSequenceNumber ( const uint16_t seqNumber )

Set a sequence number

Parameters

[in] seqNumber The sequence number to set

Returns: True if the value was set successfully, false otherwise. In case of failure a corresponding error message will be written to log

◆ toString()

std::string pcpp::GtpV1Layer::toString ( ) const

virtual

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

Implements pcpp::Layer.

Classes

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ GtpV1Layer() [1/3]

◆ GtpV1Layer() [2/3]

◆ GtpV1Layer() [3/3]

Member Function Documentation

◆ addExtension()

◆ computeCalculateFields()

◆ getHeader()

◆ getHeaderLen()

◆ getMessageType()

◆ getMessageTypeAsString()

◆ getNextExtension()

◆ getNextExtensionHeaderType()

◆ getNpduNumber()

◆ getOsiModelLayer()

◆ getSequenceNumber()

◆ isGTPCMessage()

◆ isGTPUMessage()

◆ isGTPv1()

◆ isGTPv1Port()

◆ parseNextLayer()

◆ setNpduNumber()

◆ setSequenceNumber()

◆ toString()