Package net.i2p.client.datagram

Class 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!
    Author:
    human

    • Constructor Summary

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

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method 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)

    • Constructor Detail

      • I2PDatagramDissector

        public I2PDatagramDissector()
        Crate a new I2P repliable datagram dissector.

    • Method Detail

      • 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

      • 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

      • 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

      • 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

      • 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