Internet protocol (v4) utility. More...

Functions
function ip4Addr	get ()
	Retrieve the IPv4 address. More...

function ip4Addr	set (ip)
	Set the IPv4 address. More...

function ip4Addr	setString (ip)
	Set the IPv4 address. More...

function ip4Addr	getString ()
	Retrieve the string representation of the IPv4 address. More...

function ip4Addr	__eq (lhs, rhs)
	Test equality of two IPv4 addresses. More...

function ip4Addr	__add (lhs, rhs)
	Add a number to an IPv4 address. More...

function ip4Addr	add (val)
	Add a number to an IPv4 address in-place. More...

function ip4Addr	__sub (val)
	Subtract a number from an IPv4 address. More...

function ip4Header	setVersion (int)
	Set the version. More...

function ip4Header	getVersion ()
	Retrieve the version. More...

function ip4Header	getVersionString ()
	Retrieve the version. More...

function ip4Header	setHeaderLength (int)
	Set the header length. More...

function ip4Header	getHeaderLength ()
	Retrieve the header length. More...

function ip4Header	getHeaderLengthString ()
	Retrieve the header length. More...

function ip4Header	setTOS (int)
	Set the type of service (TOS). More...

function ip4Header	getTOS ()
	Retrieve the type of service. More...

function ip4Header	getTOSString ()
	Retrieve the type of service. More...

function ip4Header	setLength (int)
	Set the total length. More...

function ip4Header	getLength ()
	Retrieve the length. More...

function ip4Header	getLengthString ()
	Retrieve the length. More...

function ip4Header	setID (int)
	Set the identification. More...

function ip4Header	getID ()
	Retrieve the identification. More...

function ip4Header	getIDString ()
	Retrieve the identification. More...

function ip4Header	setFlags (int)
	Set the flags. More...

function ip4Header	getFlags ()
	Retrieve the flags. More...

function ip4Header	getFlagsString ()
	Retrieve the flags. More...

function ip4Header	setFragment (int)
	Set the fragment. More...

function ip4Header	getFragment ()
	Retrieve the fragment. More...

function ip4Header	getFragmentString ()
	Retrieve the fragemt. More...

function ip4Header	setTTL (int)
	Set the time-to-live (TTL). More...

function ip4Header	getTTL ()
	Retrieve the time-to-live. More...

function ip4Header	getTTLString ()
	Retrieve the time-to-live. More...

function ip4Header	setProtocol (int)
	Set the next layer protocol. More...

function ip4Header	getProtocol ()
	Retrieve the next layer protocol. More...

function ip4Header	getProtocolString ()
	Retrieve the next layer protocol. More...

function ip4Header	setChecksum (int)
	Set the checksum. More...

function ip4Header	getChecksum ()
	Retrieve the checksum. More...

function ip4Header	getChecksumString ()
	Retrieve the checksum. More...

function ip4Header	calculateChecksum ()
	Calculate and set the checksum. More...

function ip4Header	setDst (int)
	Set the destination address. More...

function ip4Header	getDst ()
	Retrieve the destination IP address. More...

function ip4Header	setSrc (int)
	Set the source address. More...

function ip4Header	getSrc ()
	Retrieve the source IP address. More...

function ip4Header	setDstString (str)
	Set the destination address. More...

function ip4Header	getDstString ()
	Retrieve the destination IP address. More...

function ip4Header	setSrcString (str)
	Set the source address. More...

function ip4Header	getSrcString ()
	Retrieve the source IP address. More...

function ip4Header	fill (args, pre)
	Set all members of the ip header. More...

function ip4Header	get (pre)
	Retrieve the values of all members. More...

function ip4Header	resolveNextHeader ()
	Resolve which header comes after this one (in a packet). More...

function ip4Header	setDefaultNamedArgs (pre, namedArgs, nextHeader, accumulatedLength)
	Change the default values for namedArguments (for fill/get). More...

Variables
local	ip = {}
	IP4 protocol constants.

ip	PROTO_ICMP = 0x01
	Protocol field value for Icmp.

ip	PROTO_TCP = 0x06
	Protocol field value for Tcp.

ip	PROTO_UDP = 0x11
	Protocol field value for Udp.

local	ip4Addr = {}
	Module for ip4_address struct (see headers.lua).

local	ip4Header = {}
	Module for ip4_header struct (see headers.lua).

pkt	getIP4Packet = packetCreate("eth", "ip4")
	Cast the packet to an IP4 packet.

pkt	getIPPacket = function(self, ip4)
	Cast the packet to either an IP4 (nil/true) or IP6 (false) packet, depending on the passed boolean.

Detailed Description

Internet protocol (v4) utility.

Utility functions for the ip4_address and ip4_header structs defined in headers.lua .
Includes:

IP4 constants
IP4 address utility
IP4 header utility
Definition of IP4 packets

Definition in file ip4.lua.

Function Documentation

function ip4Addr __add	(	lhs	,
		rhs
	)

Add a number to an IPv4 address.

Max. 32 bit, commutative.

Parameters

lhs	Address in 'union ip4_address' format.
rhs	Number to add (32 bit integer).

Returns: Resulting address in uint32 format.

function ip4Addr __eq	(	lhs	,
		rhs
	)

Test equality of two IPv4 addresses.

Parameters

lhs	Address in 'union ip4_address' format.
rhs	Address in 'union ip4_address' format.

Returns: true if equal, false otherwise.

function ip4Addr __sub ( val )

Subtract a number from an IPv4 address.

Max. 32 bit.

Parameters

val	Number to substract (32 bit integer)

Returns: Resulting address in uint32 format.

function ip4Addr add ( val )

Add a number to an IPv4 address in-place.

Max. 32 bit.

Parameters

val	Number to add (32 bit integer).

Examples:: l3-tcp-syn-flood.lua.

function ip4Header calculateChecksum ( )

Calculate and set the checksum.

If possible use checksum offloading instead.

See Also: pkt:offloadUdpChecksum

function ip4Header fill	(	args	,
		pre
	)

Set all members of the ip header.

Per default, all members are set to default values specified in the respective set function. Optional named arguments can be used to set a member to a user-provided value.

Parameters

args	Table of named arguments. Available arguments: Version, HeaderLength, TOS, Length, ID, Flags, Fragment, TTL, Protocol, Checksum, Src, Dst
pre	prefix for namedArgs. Default 'ip4'. fill() --- only default values fill{ ipSrc="1.1.1.1", ipTTL=100 } --- all members are set to default values with the exception of ipSrc and ipTTL

function ip4Addr get ( )

Retrieve the IPv4 address.

Returns: Address in uint32 format.

function ip4Header get ( pre )

Retrieve the values of all members.

Parameters

pre	prefix for namedArgs. Default 'ip4'.

Returns: Table of named arguments. For a list of arguments see "See also".

See Also: ip4Header:fill

function ip4Header getChecksum ( )

Retrieve the checksum.

Returns: Checksum as 16 bit integer.

function ip4Header getChecksumString ( )

Retrieve the checksum.

Returns: Checksum as string.

function ip4Header getDst ( )

Retrieve the destination IP address.

Returns: Address in 'union ip4_address' format.

function ip4Header getDstString ( )

Retrieve the destination IP address.

Returns: Address in string format.

function ip4Header getFlags ( )

Retrieve the flags.

Returns: Flags as 3 bit integer.

function ip4Header getFlagsString ( )

Retrieve the flags.

Returns: Flags as string.

function ip4Header getFragment ( )

Retrieve the fragment.

Returns: Fragment as 13 bit integer.

function ip4Header getFragmentString ( )

Retrieve the fragemt.

Returns: Fragment as string.

function ip4Header getHeaderLength ( )

Retrieve the header length.

Returns: Header length as 4 bit integer.

function ip4Header getHeaderLengthString ( )

Retrieve the header length.

Returns: Header length as string.

function ip4Header getID ( )

Retrieve the identification.

Returns: ID as 16 bit integer.

function ip4Header getIDString ( )

Retrieve the identification.

Returns: ID as string.

function ip4Header getLength ( )

Retrieve the length.

Returns: Length as 16 bit integer.

function ip4Header getLengthString ( )

Retrieve the length.

Returns: Length as string.

function ip4Header getProtocol ( )

Retrieve the next layer protocol.

Returns: Next layer protocol as 8 bit integer.

function ip4Header getProtocolString ( )

Retrieve the next layer protocol.

Returns: Next layer protocol as string.

function ip4Header getSrc ( )

Retrieve the source IP address.

Returns: Address in 'union ip4_address' format.

function ip4Header getSrcString ( )

Retrieve the source IP address.

Returns: Address in string format.

function ip4Addr getString ( )

Retrieve the string representation of the IPv4 address.

Retrieve the values of all members.

Returns: Address in string format.; Values in string format.

function ip4Header getTOS ( )

Retrieve the type of service.

Returns: TOS as 8 bit integer.

function ip4Header getTOSString ( )

Retrieve the type of service.

Returns: TOS as string.

function ip4Header getTTL ( )

Retrieve the time-to-live.

Returns: TTL as 8 bit integer.

function ip4Header getTTLString ( )

Retrieve the time-to-live.

Returns: TTL as string.

function ip4Header getVersion ( )

Retrieve the version.

Returns: Version as 4 bit integer.

function ip4Header getVersionString ( )

Retrieve the version.

Returns: Version as string.

function ip4Header resolveNextHeader ( )

Resolve which header comes after this one (in a packet).

For instance: in tcp/udp based on the ports. This function must exist and is only used when get/dump is executed on an unknown (mbuf not yet casted to e.g. tcpv6 packet) packet (mbuf)

Returns: String next header (e.g. 'udp', 'icmp', nil)

function ip4Addr set ( ip )

Set the IPv4 address.

Parameters

ip	Address in uint32 format.

function ip4Header setChecksum ( int )

Set the checksum.

Parameters

int	Checksum of the ip header as 16 bit integer.

See Also: ip4Header:calculateChecksum; pkt:offloadUdpChecksum

function ip4Header setDefaultNamedArgs	(	pre	,
		namedArgs	,
		nextHeader	,
		accumulatedLength
	)

Change the default values for namedArguments (for fill/get).

This can be used to for instance calculate a length value based on the total packet length. See proto/ip4.setDefaultNamedArgs as an example. This function must exist and is only used by packet.fill.

Parameters

pre	The prefix used for the namedArgs, e.g. 'ip4'
namedArgs	Table of named arguments (see See Also)
nextHeader	The header following after this header in a packet
accumulatedLength	The so far accumulated length for previous headers in a packet

Returns: Table of namedArgs

See Also: ip4Header:fill

function ip4Header setDst ( int )

Set the destination address.

Parameters

int	Address in 'union ip4_address' format.

function ip4Header setDstString ( str )

Set the destination address.

Parameters

str	Address in string format.

function ip4Header setFlags ( int )

Set the flags.

Bits: [ reserved (must be 0) | don't fragment | more fragments ]

Parameters

int	Flags of the ip header as 3 bit integer

function ip4Header setFragment ( int )

Set the fragment.

Parameters

int	Fragment of the ip header as 13 bit integer.

function ip4Header setHeaderLength ( int )

Set the header length.

Parameters

int	Length of the ip header (in multiple of 32 bits) as 4 bit integer. Should always be '5'.

function ip4Header setID ( int )

Set the identification.

Parameters

int	ID of the ip header as 16 bit integer.

function ip4Header setLength ( int )

Set the total length.

Parameters

int	Length of the packet excluding layer 2. 16 bit integer.

function ip4Header setProtocol ( int )

Set the next layer protocol.

Parameters

int	Next layer protocol of the ip header as 8 bit integer.

function ip4Header setSrc ( int )

Set the source address.

Parameters

int	Address in 'union ip4_address' format.

function ip4Header setSrcString ( str )

Set the source address.

Parameters

str	Address in string format.

function ip4Addr setString ( ip )

Set the IPv4 address.

Parameters

ip	Address in string format.

function ip4Header setTOS ( int )

Set the type of service (TOS).

Parameters

int	TOS of the ip header as 8 bit integer.

function ip4Header setTTL ( int )

Set the time-to-live (TTL).

Parameters

int	TTL of the ip header as 8 bit integer.

function ip4Header setVersion ( int )

Set the version.

Parameters

int	IP header version as 4 bit integer. Should always be '4'.

Functions

Variables

Detailed Description

Function Documentation