This class provides several methods that can be used by elements that inherits from it to manage TCP packets. More...

#include <tcphelper.hh>

Inheritance diagram for TCPHelper:

Public Member Functions
WritablePacket *	forgeRst (Packet *packet)

WritablePacket *	forgePacket (uint32_t saddr, uint32_t daddr, uint16_t sport, uint16_t dport, tcp_seq_t seq, tcp_seq_t ack, uint16_t winSize, uint8_t flags, uint32_t contentSize=0) const
	Create a TCP packet.

uint16_t	getDestinationPort (Packet *packet) const
	Return the destination port of a packet.

uint16_t	getSourcePort (Packet *packet) const
	Return the source port of a packet.

tcp_seq_t	getNextSequenceNumber (Packet *packet) const
	Return the sequence number of the packet that will be received after the given one.

uint16_t	getWindowSize (Packet *packet) const
	Return the window size set in the header of a packet.

void	setWindowSize (WritablePacket *packet, uint16_t winSize) const
	Set the window size in the TCP header of a packet.

unsigned char *	getPayload (WritablePacket *packet) const
	Return the payload of a TCP packet.

const unsigned char *	getPayloadConst (Packet *packet) const
	Return the payload of a TCP packet.

uint16_t	getPayloadOffset (Packet *packet) const
	Return the offset of the payload in a TCP packet.

void	setPayload (WritablePacket packet, const unsigned char payload, uint32_t length) const
	Set the payload of a TCP packet.

void	setSequenceNumber (WritablePacket *packet, tcp_seq_t seq) const
	Set the sequence number of a TCP packet.

void	setAckNumber (WritablePacket *packet, tcp_seq_t ack) const
	Set the ack number of a TCP packet.

uint8_t	getFlags (Packet *packet) const
	Return the flags of a TCP packet.

Public Member Functions inherited from IPHelper
uint16_t	packetTotalLength (Packet *packet) const
	Return the length of the IP packet, obtained from the header.

uint16_t	getIPHeaderOffset (Packet *packet) const
	Return the offset in the packet at which the IP header starts.

void	setPacketTotalLength (WritablePacket *packet, unsigned length) const
	Set the length of the IP packet in the header.

uint32_t	getDestinationAddress (Packet *packet) const
	Return the IP destination address of the packet.

uint32_t	getSourceAddress (Packet *packet) const
	Return the IP source address of the packet.

void	computeIPChecksum (WritablePacket *packet) const
	Recompute the IP checksum of the packet and set it in the IP header.

void	rewrite_ipport (WritablePacket *p, IPAddress ip, uint16_t port, const int shift, bool is_tcp)

Static Public Member Functions
static tcp_seq_t	getSequenceNumber (Packet *packet)
	Return the sequence number of a packet.

static tcp_seq_t	getAckNumber (Packet *packet)
	Return the ack number of a packet.

static bool	isTCP (Packet *packet)
	Indicate whether a packet is a TCP packet.

static bool	isSyn (Packet *packet)
	Indicate whether a packet is a SYN packet.

static bool	isFin (Packet *packet)
	Indicate whether a packet is a FIN packet.

static bool	isRst (Packet *packet)
	Indicate whether a packet is a RST packet.

static bool	isAck (Packet *packet)
	Indicate whether a packet is an ACK packet.

static bool	checkFlag (Packet *packet, uint8_t flag)
	Check if a given flag is set in a packet.

static unsigned	getPayloadLength (Packet *packet)
	Return the length of the TCP payload of a packet.

static bool	isJustAnAck (Packet *packet, const bool or_fin=false)
	Indicate whether the packet is just an ACK without any additional information.

static void	computeTCPChecksum (WritablePacket *packet)
	Compute the TCP checksum of a packet and set it in its header.

static void	resetTCPChecksum (WritablePacket *packet)
	Reset the TCP checksum of a packet and set it in its header.

static int	iterateOptions (Packet packet, std::function< bool(uint8_t, void )> fnt)

static void	printPacket (Packet *p)

Detailed Description

This class provides several methods that can be used by elements that inherits from it to manage TCP packets.

Member Function Documentation

◆ forgePacket()

WritablePacket * TCPHelper::forgePacket	(	uint32_t	saddr,
		uint32_t	daddr,
		uint16_t	sport,
		uint16_t	dport,
		tcp_seq_t	seq,
		tcp_seq_t	ack,
		uint16_t	winSize,
		uint8_t	flags,
		uint32_t	contentSize = `0`
	)		const

Create a TCP packet.

Parameters

saddr	Source IP address
daddr	Destination IP address
sport	Source port
dport	Destination port
seq	Sequence number
ack	Ack number
windowSize	Window size
flags	The TCP flags on one byte
contentSize	Extra space to allocate for the TCP payload

Returns: The created TCP packet

◆ getDestinationPort()

uint16_t TCPHelper::getDestinationPort ( Packet * packet ) const

inline

Return the destination port of a packet.

Parameters

packet The packet

Returns: The destination port of the packet

◆ getSourcePort()

uint16_t TCPHelper::getSourcePort ( Packet * packet ) const

inline

Return the source port of a packet.

Parameters

packet The packet

Returns: The source port of the packet

◆ getSequenceNumber()

tcp_seq_t TCPHelper::getSequenceNumber ( Packet * packet )

inlinestatic

Return the sequence number of a packet.

Parameters

packet The packet

Returns: The sequence number of the packet

◆ getAckNumber()

tcp_seq_t TCPHelper::getAckNumber ( Packet * packet )

inlinestatic

Return the ack number of a packet.

Parameters

packet The packet

Returns: The ack number of the packet

◆ getNextSequenceNumber()

tcp_seq_t TCPHelper::getNextSequenceNumber ( Packet * packet ) const

inline

Return the sequence number of the packet that will be received after the given one.

Parameters

fcb	A pointer to the FCB of the flow
packet	The packet to check

Returns: The sequence number of the packet after the given one

◆ getWindowSize()

uint16_t TCPHelper::getWindowSize ( Packet * packet ) const

inline

Return the window size set in the header of a packet.

Parameters

packet The packet

Returns: The window size set in the header of the packet

◆ setWindowSize()

void TCPHelper::setWindowSize	(	WritablePacket *	packet,
		uint16_t	winSize
	)		const

inline

Set the window size in the TCP header of a packet.

Parameters

packet	The packet
winSize	The window size

◆ isTCP()

bool TCPHelper::isTCP ( Packet * packet )

inlinestatic

Indicate whether a packet is a TCP packet.

Parameters

packet The packet

Returns: A boolean indicating whether the packet is a TCP packet

◆ isSyn()

bool TCPHelper::isSyn ( Packet * packet )

inlinestatic

Indicate whether a packet is a SYN packet.

Parameters

packet The packet

Returns: A boolean indicating whether the packet is a SYN packet

◆ isFin()

bool TCPHelper::isFin ( Packet * packet )

inlinestatic

Indicate whether a packet is a FIN packet.

Parameters

packet The packet

Returns: A boolean indicating whether the packet is a FIN packet

◆ isRst()

bool TCPHelper::isRst ( Packet * packet )

inlinestatic

Indicate whether a packet is a RST packet.

Parameters

packet The packet

Returns: A boolean indicating whether the packet is a RST packet

◆ isAck()

bool TCPHelper::isAck ( Packet * packet )

inlinestatic

Indicate whether a packet is an ACK packet.

Parameters

packet The packet

Returns: A boolean indicating whether the packet is an ACK packet

◆ checkFlag()

bool TCPHelper::checkFlag	(	Packet *	packet,
		uint8_t	flag
	)

inlinestatic

Check if a given flag is set in a packet.

Parameters

packet	The packet
flag	The offset of the flag

Returns: A boolean indicating whether the flag is set in the packet

◆ getPayloadLength()

unsigned TCPHelper::getPayloadLength ( Packet * packet )

inlinestatic

Return the length of the TCP payload of a packet.

Parameters

packet The packet

Returns: The length of the TCP payload of the packet

◆ getPayload()

unsigned char * TCPHelper::getPayload ( WritablePacket * packet ) const

inline

Return the payload of a TCP packet.

Parameters

packet The packet

Returns: The payload of the packet

◆ getPayloadConst()

const unsigned char * TCPHelper::getPayloadConst ( Packet * packet ) const

inline

Return the payload of a TCP packet.

Parameters

packet The packet

Returns: The const payload of the packet

◆ getPayloadOffset()

uint16_t TCPHelper::getPayloadOffset ( Packet * packet ) const

inline

Return the offset of the payload in a TCP packet.

Parameters

packet The packet

Returns: The offset of the payload in a TCP packet

◆ setPayload()

void TCPHelper::setPayload	(	WritablePacket *	packet,
		const unsigned char *	payload,
		uint32_t	length
	)		const

inline

Set the payload of a TCP packet.

Parameters

packet	The packet
payload	The new value of the payload
length	The length of the payload

◆ setSequenceNumber()

void TCPHelper::setSequenceNumber	(	WritablePacket *	packet,
		tcp_seq_t	seq
	)		const

inline

Set the sequence number of a TCP packet.

Parameters

packet	The packet
seq	The sequence number of the packet

◆ setAckNumber()

void TCPHelper::setAckNumber	(	WritablePacket *	packet,
		tcp_seq_t	ack
	)		const

inline

Set the ack number of a TCP packet.

Parameters

packet	The packet
ack	The ack number of the packet

◆ isJustAnAck()

bool TCPHelper::isJustAnAck	(	Packet *	packet,
		const bool	or_fin = `false`
	)

inlinestatic

Indicate whether the packet is just an ACK without any additional information.

Parameters

packet The packet

Returns: A boolean indicating whether the packet is just an ACK without any additional information

◆ getFlags()

uint8_t TCPHelper::getFlags ( Packet * packet ) const

inline

Return the flags of a TCP packet.

Parameters

packet The packet

Returns: A byte containing the flags of the packet

◆ computeTCPChecksum()

void TCPHelper::computeTCPChecksum ( WritablePacket * packet )

inlinestatic

Compute the TCP checksum of a packet and set it in its header.

Parameters

packet The packet

◆ resetTCPChecksum()

void TCPHelper::resetTCPChecksum ( WritablePacket * packet )

inlinestatic

Reset the TCP checksum of a packet and set it in its header.

Parameters

packet The packet

The documentation for this class was generated from the following files:

include/click/tcphelper.hh
lib/tcphelper.cc

Public Member Functions

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ forgePacket()

◆ getDestinationPort()

◆ getSourcePort()

◆ getSequenceNumber()

◆ getAckNumber()

◆ getNextSequenceNumber()

◆ getWindowSize()

◆ setWindowSize()

◆ isTCP()

◆ isSyn()

◆ isFin()

◆ isRst()

◆ isAck()

◆ checkFlag()

◆ getPayloadLength()

◆ getPayload()

◆ getPayloadConst()

◆ getPayloadOffset()

◆ setPayload()

◆ setSequenceNumber()

◆ setAckNumber()

◆ isJustAnAck()

◆ getFlags()

◆ computeTCPChecksum()

◆ resetTCPChecksum()