Package nl.sidnlabs.pcap.decoder

Class IPDecoder

java.lang.Object

nl.sidnlabs.pcap.decoder.IPDecoder

public class IPDecoder
extends Object

Decode the IP header

Field Summary

Fields

Modifier and Type	Field	Description
static final int	IP_FLAGS
static final int	IP_FRAGMENT_OFFSET
static final int	IP_PROTOCOL_VERSION_4
static final int	IP_PROTOCOL_VERSION_6
static final int	IP_TOTAL_LEN_OFFSET

Constructor Summary

Constructors

Constructor	Description
IPDecoder(Decoder tcpReader, Decoder udpReader, ICMPDecoder icmpDecoder)

Method Summary

Modifier and Type	Method	Description
void	clearCache(int ipFragmentTTL)	Clear expired cache entries in order to avoid memory problems
Packet	createPacket(byte[] packetData, int ipStart)
Packet	decode(byte[] packetData, int ipStart, long packetTimestampSecs, long packetTimestampMicros, boolean partial)
Packet	decode(Packet packet)
Packet	decode(Packet packet, byte[] packetData, int ipStart)
com.google.common.collect.Multimap<Datagram,DatagramPayload>	getDatagrams()
void	printStats()
byte[]	reassemble(Packet packet, byte[] packetData)	Reassemble the IP packet is it is fragmented.
void	reset()
void	setDatagrams(com.google.common.collect.Multimap<Datagram,DatagramPayload> datagrams)
void	setTcpFlows(Map<TCPFlow,FlowData> flows)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

IP_PROTOCOL_VERSION_4

public static final int IP_PROTOCOL_VERSION_4

See Also:

• Constant Field Values

IP_PROTOCOL_VERSION_6

public static final int IP_PROTOCOL_VERSION_6

See Also:

• Constant Field Values

IP_TOTAL_LEN_OFFSET

public static final int IP_TOTAL_LEN_OFFSET

See Also:

• Constant Field Values

IP_FLAGS

public static final int IP_FLAGS

See Also:

• Constant Field Values

IP_FRAGMENT_OFFSET

public static final int IP_FRAGMENT_OFFSET

See Also:

• Constant Field Values

Constructor Details

IPDecoder

public IPDecoder(Decoder tcpReader,
 Decoder udpReader,
 ICMPDecoder icmpDecoder)

Method Details

printStats

public void printStats()

decode

public Packet decode(byte[] packetData,
 int ipStart,
 long packetTimestampSecs,
 long packetTimestampMicros,
 boolean partial)

decode

public Packet decode(Packet packet)

decode

public Packet decode(Packet packet,
 byte[] packetData,
 int ipStart)

createPacket

public Packet createPacket(byte[] packetData,
 int ipStart)

reassemble

public byte[] reassemble(Packet packet,
 byte[] packetData)

Reassemble the IP packet is it is fragmented. If it is not fragmented then the packetData bytes are returned as result. If the packet is fragmented and this packet is the final fragment then all the bytes from the fragments are concatenated and returned. if fragmented and current fragment is not yet the final fragment then an empty byte array is returned. the

Parameters:

packet - the current packet

packetData - the payload of the current packet

Returns:

input, reassembled or no bytes

getDatagrams

public com.google.common.collect.Multimap<Datagram,DatagramPayload> getDatagrams()

setDatagrams

public void setDatagrams(com.google.common.collect.Multimap<Datagram,DatagramPayload> datagrams)

setTcpFlows

public void setTcpFlows(Map<TCPFlow,FlowData> flows)

clearCache

public void clearCache(int ipFragmentTTL)

Clear expired cache entries in order to avoid memory problems

Parameters:

ipFragmentTTL - timeout for IP fragments

reset

public void reset()