net.i2p.client.datagram

Class I2PDatagramDissector

java.lang.Object

net.i2p.client.datagram.I2PDatagramDissector

public final class I2PDatagramDissector
extends Object

Class for dissecting I2P repliable datagrams, checking the authenticity of the sender. Note that objects of this class are NOT THREAD SAFE!

Constructor Summary

Constructors

Constructor and Description
I2PDatagramDissector() Crate a new I2P repliable datagram dissector.

Method Summary

Modifier and Type	Method and Description
Hash	extractHash() Extract the hash of the payload of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), without verifying the datagram signature.
byte[]	extractPayload() Extract the payload carried by an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), without verifying the datagram signature.
Destination	extractSender() Extract the sender of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), without verifying the datagram signature.
Hash	getHash() Extract the hash of the payload of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), verifying the datagram signature.
byte[]	getPayload() Get the payload carried by an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), verifying the datagram signature.
Destination	getSender() Get the sender of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), verifying the datagram signature.
void	loadI2PDatagram(byte[] dgram) Load an I2P repliable datagram into the dissector.
void	verifySignature() Verify the signature of this datagram (previously loaded with the loadI2PDatagram() method)

Methods inherited from class java.lang.Object

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

Constructor Detail

I2PDatagramDissector

public I2PDatagramDissector()

Crate a new I2P repliable datagram dissector.

Method Detail

extractHash

public Hash extractHash()

Extract the hash of the payload of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), without verifying the datagram signature. As of 0.9.14, for signature types other than DSA_SHA1, this returns null.

Returns:

The hash of the payload of the I2P repliable datagram

extractPayload

public byte[] extractPayload()

Extract the payload carried by an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), without verifying the datagram signature.

Returns:

A byte array containing the datagram payload

extractSender

public Destination extractSender()

Extract the sender of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), without verifying the datagram signature.

Returns:

The Destination of the I2P repliable datagram sender

getHash

public Hash getHash()
             throws I2PInvalidDatagramException

Extract the hash of the payload of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), verifying the datagram signature. As of 0.9.14, for signature types other than DSA_SHA1, this returns null.

Returns:

The hash of the payload of the I2P repliable datagram

Throws:

I2PInvalidDatagramException - if the signature verification fails

getPayload

public byte[] getPayload()
                  throws I2PInvalidDatagramException

Get the payload carried by an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), verifying the datagram signature.

Returns:

A byte array containing the datagram payload

Throws:

I2PInvalidDatagramException - if the signature verification fails

getSender

public Destination getSender()
                      throws I2PInvalidDatagramException

Get the sender of an I2P repliable datagram (previously loaded with the loadI2PDatagram() method), verifying the datagram signature.

Returns:

The Destination of the I2P repliable datagram sender

Throws:

I2PInvalidDatagramException - if the signature verification fails

loadI2PDatagram

public void loadI2PDatagram(byte[] dgram)
                     throws DataFormatException

Load an I2P repliable datagram into the dissector. Does NOT verify the signature. Format is:

1. Destination (387+ bytes)
2. Signature (40+ bytes, type and length as implied by signing key type in the Destination)
3. Payload

For DSA_SHA1 Destinations, the signature is of the SHA-256 Hash of the payload. As of 0.9.14, for non-DSA_SHA1 Destinations, the signature is of the payload itself.

Parameters:

dgram - non-null I2P repliable datagram to be loaded

Throws:

DataFormatException - If there's an error in the datagram format

verifySignature

public void verifySignature()
                     throws I2PInvalidDatagramException

Verify the signature of this datagram (previously loaded with the loadI2PDatagram() method)

Throws:

I2PInvalidDatagramException - if the signature is invalid