Nettle.IPv4.IPPacket

Contents

Description

This module provides Get values for parsing various IP packets and headers from ByteStrings into a byte-sequence-independent representation as Haskell datatypes.

Warning:

These are incomplete. The headers may not contain all the information that the protocols specify. For example, the Haskell representation of an IP Header only includes source and destination addresses and IP protocol number, even though an IP packet has many more header fields. More seriously, an IP header may have an optional extra headers section after the destination address. We assume this is not present. If it is present, then the transport protocol header will not be directly after the destination address, but will be after these options. Therefore functions that assume this, such as the getExactMatch function below, will give incorrect results when applied to such IP packets.

The Haskell representations of the headers for the transport protocols are similarly incomplete. Again, the Get instances for the transport protocols may not parse through the end of the transport protocol header.

Synopsis

IP Packet

data IPPacket Source

An IP packet consists of a header and a body.

Constructors

IPPacket IPHeader IPBody

Instances

Eq IPPacket
Show IPPacket
FramedMessage IPPacket IPAddress IPBody

data IPHeader Source

An IP Header includes various information about the packet, including the type of payload it contains. Warning: this definition does not include every header field included in an IP packet.

Constructors

IPHeader
Fields ipSrcAddress :: IPAddress ipDstAddress :: IPAddress ipProtocol :: IPProtocol headerLength :: Int totalLength :: Int dscp :: DifferentiatedServicesCodePoint differentiated services code point - 6 bit number

Instances

Eq IPHeader
Read IPHeader
Show IPHeader

type DifferentiatedServicesCodePoint = Word8 Source

type FragOffset = Word16 Source

type IPProtocol = Word8 Source

type IPTypeOfService = Word8 Source

type TransportPort = Word16 Source

ipTypeTcp :: IPProtocol Source

ipTypeUdp :: IPProtocol Source

ipTypeIcmp :: IPProtocol Source

data IPBody Source

The body of an IP packet can be either a TCP, UDP, ICMP or other packet. Packets other than TCP, UDP, ICMP are represented as unparsed ByteString values.

Constructors