Package org.activecomponents.udp

Class Connection

java.lang.Object

org.activecomponents.udp.Connection

public class Connection
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field	Description
protected static byte	ACK	Acknowledgement of a message part.
protected SymCipherManagement	ciphermgmt	Management object for symmetric ciphers.
protected boolean	connected	Flag that defines if the connection is currently active.
protected java.util.List<IConnectionListener>	connectionlisteners	Listeners for new connections.
static byte	DATA	Data package after connection handshake.
protected static boolean	DEBUG	Debug flag.
protected static byte	FIN	Packet type for closing a connection.
protected static byte	FINACK	Packet type for confirming a closed connection.
protected IIncomingListener	inclistener	Listener for incoming messages and packets.
protected java.util.Random	insecrandom	Insecure PRNG.
protected static byte	INT_MESSAGE_PART	Part of an internal message.
protected java.util.concurrent.LinkedBlockingQueue<byte[]>	internalpackets	Arrived packets that are used to manage the connection
protected static byte	KEEPALIVE	Keepalive packet.
protected long	keepalivereceived	Timestamp of the last received keepalive packet.
protected long	keepalivesent	Timestamp of the last sent keepalive packet.
protected byte[]	keypackage	Key package built during connection establishment.
protected java.util.List<IKeyVerifier>	keyverifiers	List of externally-provided key verifiers.
protected long	latency	Current latency.
protected static byte	MESSAGE_PART	Part of a message.
protected java.util.Queue<OutgoingMessage>	messagequeue	Queue of scheduled messages.
protected java.util.Map<java.lang.Long,IncomingMessage>	messages	Incoming messages
protected static byte	PACKET	Packet with data requiring no confirmation.
protected java.util.LinkedList<MessagePart>	queuedmessageparts	Parts of messages that have been queued and awaiting transmission.
protected static byte	RDY	Response to a SYNACK, confirming readiness by the initiator.
protected static byte	REKEY	Message type used to rekey the connection.
protected IUdpCallback<java.lang.Boolean>	rekeycallback
protected java.net.SocketAddress	remoteaddr	The remote peer this connection targets.
protected java.util.Map<java.lang.Long,MessagePart>	sentwindow	Message parts that have been sent and await confirmation.
protected java.net.DatagramSocket	socket	The socket.
protected static byte	SYN	Packet type for initiating a connection.
protected static byte	SYNACK	Response to a SYN, finalizing the key exchange.
protected IThreadExecutor	texec	The thread executor.
protected java.util.concurrent.LinkedBlockingQueue<byte[]>	userpackets	User packets with a payload.
protected int	windowsize	Current window size.
protected int	windowthres	Window size threshold.

Constructor Summary

Constructors

Constructor	Description
Connection(java.net.DatagramSocket socket, java.util.List<IConnectionListener> connectionlisteners, java.net.SocketAddress remoteaddr, IThreadExecutor texec, KeyExchangeGenerator keyexgen, int symcipherclassid, java.util.List<IKeyVerifier> keyverifiers, IIncomingListener inclistener)

Method Summary

Modifier and Type	Method	Description
protected byte[]	buildSignedKeyPackage(byte[] localpubkey, byte[] remotepubkey)	Builds a signed package of local and remote public key.
protected void	clearQueues()	Clears internal buffers.
protected void	connectionEstablished(UdpConnectionHandler handler, java.net.DatagramPacket confirmation)	Called when the connection has been established.
protected byte[]	createUserPacket(byte[] packet)	Creates a prepared packet as encrypted user packet.
protected void	disconnect()	Notifies the remote host of a disconnect and terminates the connection.
protected byte[]	extractAndVerifyPubKey(byte[] localpubkey, byte[] buffer, int offset)	Verifies a signed package of local and remote public key.
java.net.SocketAddress	getRemoteAddress()	Returns the remote address.
protected void	initiate(UdpConnectionHandler handler)	Method for initiating the connection.
boolean	isConnected()	Checks if the connection is working.
protected void	processInternalMessage(byte[] incmsg)	Processes an internal message.
protected void	rawPacketReceived(byte[] data)	Called when a package is received.
byte[]	receive()	Receives a message / packet (blocking).
byte[]	receive(long timeout)	Receives a message / packet (blocking).
protected void	respond(byte[] initial, UdpConnectionHandler handler)	Response actions for an attempt to initate a connection.
protected void	scheduleMessage(OutgoingMessage msg, boolean internal)
protected void	sendLoop()	Loop for dispatching packets to the remote host.
void	sendMessage(byte[] msg)	Send a message.
void	sendMessage(byte[] msg, IUdpCallback<java.lang.Boolean> callback)	Send a message.
void	sendPacket(byte[] data)	Sends a packet.
protected void	userPacketReceived(SymCipherSuite ciphersuite, byte[] data)	Method for handling decrypted user-level packets.

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

protected static final boolean DEBUG

Debug flag.

See Also:

Constant Field Values

SYN

protected static final byte SYN

Packet type for initiating a connection.

See Also:

Constant Field Values

SYNACK

protected static final byte SYNACK

Response to a SYN, finalizing the key exchange.

See Also:

Constant Field Values

RDY

protected static final byte RDY

Response to a SYNACK, confirming readiness by the initiator.

See Also:

Constant Field Values

DATA

public static final byte DATA

Data package after connection handshake.

See Also:

Constant Field Values

KEEPALIVE

protected static final byte KEEPALIVE

Keepalive packet.

See Also:

Constant Field Values

FIN

protected static final byte FIN

Packet type for closing a connection.

See Also:

Constant Field Values

FINACK

protected static final byte FINACK

Packet type for confirming a closed connection.

See Also:

Constant Field Values

ACK

protected static final byte ACK

Acknowledgement of a message part.

See Also:

Constant Field Values

PACKET

protected static final byte PACKET

Packet with data requiring no confirmation.

See Also:

Constant Field Values

MESSAGE_PART

protected static final byte MESSAGE_PART

Part of a message.

See Also:

Constant Field Values

INT_MESSAGE_PART

protected static final byte INT_MESSAGE_PART

Part of an internal message.

See Also:

Constant Field Values

REKEY

protected static final byte REKEY

Message type used to rekey the connection.

See Also:

Constant Field Values

socket

protected java.net.DatagramSocket socket

The socket.

connectionlisteners

protected java.util.List<IConnectionListener> connectionlisteners

Listeners for new connections.

keyverifiers

protected java.util.List<IKeyVerifier> keyverifiers

List of externally-provided key verifiers.

texec

protected IThreadExecutor texec

The thread executor.

remoteaddr

protected java.net.SocketAddress remoteaddr

The remote peer this connection targets.

messagequeue

protected java.util.Queue<OutgoingMessage> messagequeue

Queue of scheduled messages.

queuedmessageparts

protected java.util.LinkedList<MessagePart> queuedmessageparts

Parts of messages that have been queued and awaiting transmission.

sentwindow

protected java.util.Map<java.lang.Long,MessagePart> sentwindow

Message parts that have been sent and await confirmation.

messages

protected java.util.Map<java.lang.Long,IncomingMessage> messages

Incoming messages

windowsize

protected volatile int windowsize

Current window size.

windowthres

protected volatile int windowthres

Window size threshold.

latency

protected volatile long latency

Current latency.

insecrandom

protected java.util.Random insecrandom

Insecure PRNG.

internalpackets

protected java.util.concurrent.LinkedBlockingQueue<byte[]> internalpackets

Arrived packets that are used to manage the connection

userpackets

protected java.util.concurrent.LinkedBlockingQueue<byte[]> userpackets

User packets with a payload.

inclistener

protected IIncomingListener inclistener

Listener for incoming messages and packets.

keypackage

protected volatile byte[] keypackage

Key package built during connection establishment.

ciphermgmt

protected SymCipherManagement ciphermgmt

Management object for symmetric ciphers.

rekeycallback

protected IUdpCallback<java.lang.Boolean> rekeycallback

connected

protected volatile boolean connected

Flag that defines if the connection is currently active.

keepalivereceived

protected volatile long keepalivereceived

Timestamp of the last received keepalive packet.

keepalivesent

protected volatile long keepalivesent

Timestamp of the last sent keepalive packet.

Constructor Detail

Connection

public Connection(java.net.DatagramSocket socket,
                  java.util.List<IConnectionListener> connectionlisteners,
                  java.net.SocketAddress remoteaddr,
                  IThreadExecutor texec,
                  KeyExchangeGenerator keyexgen,
                  int symcipherclassid,
                  java.util.List<IKeyVerifier> keyverifiers,
                  IIncomingListener inclistener)

Method Detail

isConnected

public boolean isConnected()

Checks if the connection is working.

Returns:

True, if data can be send.

sendPacket

public void sendPacket(byte[] data)

Sends a packet. Maximum size is at least 60000 bytes, delivery is not guaranteed.

Parameters:

data - The data being send.

sendMessage

public void sendMessage(byte[] msg)

Send a message. Size is not limited, delivery is guaranteed unless a failure occurs.

Parameters:

msg - The message.

sendMessage

public void sendMessage(byte[] msg,
                        IUdpCallback<java.lang.Boolean> callback)

Send a message. Size is not limited, delivery is guaranteed unless a failure occurs.

Parameters:

msg - The message.

callback - Callback invoked with result of the send operation, true if the message was received, false on failure.

receive

public byte[] receive()

Receives a message / packet (blocking).

Returns:

The message/packet.

receive

public byte[] receive(long timeout)

Receives a message / packet (blocking).

Returns:

The message/packet.

getRemoteAddress

public java.net.SocketAddress getRemoteAddress()

Returns the remote address.

Returns:

Remote address.

initiate

protected void initiate(UdpConnectionHandler handler)

Method for initiating the connection.

Parameters:

handler - The handler.

respond

protected void respond(byte[] initial,
                       UdpConnectionHandler handler)

Response actions for an attempt to initate a connection.

Parameters:

initial - Initiation packaet data received that caused the response activity.

handler - The handler.

connectionEstablished

protected void connectionEstablished(UdpConnectionHandler handler,
                                     java.net.DatagramPacket confirmation)

Called when the connection has been established.

Parameters:

confirmation - Confirmation packet.

disconnect

protected void disconnect()

Notifies the remote host of a disconnect and terminates the connection.

rawPacketReceived

protected void rawPacketReceived(byte[] data)

Called when a package is received.

Parameters:

data - Raw package data.

userPacketReceived

protected void userPacketReceived(SymCipherSuite ciphersuite,
                                  byte[] data)
                           throws java.lang.Exception

Method for handling decrypted user-level packets.

Parameters:

data - Packet data.

Throws:

java.lang.Exception - Any exception that may occur and needs to be handled on a higher level.

sendLoop

protected void sendLoop()

Loop for dispatching packets to the remote host.

createUserPacket

protected byte[] createUserPacket(byte[] packet)

Creates a prepared packet as encrypted user packet.

Parameters:

packet - The inner packet.

buildSignedKeyPackage

protected byte[] buildSignedKeyPackage(byte[] localpubkey,
                                       byte[] remotepubkey)

Builds a signed package of local and remote public key.

Parameters:

localpubkey - Local public key.

remotepubkey - Remote public key.

Returns:

Signed package.

extractAndVerifyPubKey

protected byte[] extractAndVerifyPubKey(byte[] localpubkey,
                                        byte[] buffer,
                                        int offset)

Verifies a signed package of local and remote public key.

Parameters:

localpubkey - Local public key for comparison

buffer - Buffer containing package.

offset - Offset of the package.

Returns:

Extracted remote public key if verified, null if verification failed.

processInternalMessage

protected void processInternalMessage(byte[] incmsg)

Processes an internal message.

Parameters:

incmsg - The message.

scheduleMessage

protected void scheduleMessage(OutgoingMessage msg,
                               boolean internal)

clearQueues

protected void clearQueues()

Clears internal buffers.