tigase.util

Class Algorithms

java.lang.Object

tigase.util.Algorithms

public class Algorithms
extends Object

Describe class Algorithms here. Created: Wed May 4 13:24:03 2005

Version:

$Rev$

Author:

Artur Hefczyc

Method Summary

Modifier and Type	Method and Description
static void	$main(String[] args) Describe main method here.
static String	bytesToHex(byte[] buff)
static byte[]	digest(String id, String secret, String alg)
static String	generateDialbackKey(String originatingServer, String receivingServer, String secret, String streamID) Calculates dialback key as decribed in XEP-0185 version 1.0.
static String	hexDigest(String id, String secret, String alg) This method encodes data using digest algorithm described in JEP-0078 documentation.
static String	sha256(String data) Calculates SHA-256 hash of given data.

Methods inherited from class java.lang.Object

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

Method Detail

$main

public static void $main(String[] args)
                  throws Exception

Describe main method here.

Parameters:

args - a String[] value

Throws:

Exception

bytesToHex

public static final String bytesToHex(byte[] buff)

digest

public static final byte[] digest(String id,
                                  String secret,
                                  String alg)
                           throws NoSuchAlgorithmException

Throws:

NoSuchAlgorithmException

generateDialbackKey

public static String generateDialbackKey(String originatingServer,
                                         String receivingServer,
                                         String secret,
                                         String streamID)

Calculates dialback key as decribed in XEP-0185 version 1.0.

Implemented algorithm (recomended in XEP-0185):

 key = HMAC-SHA256
       (
         SHA256(Secret),
         {
           Receiving Server, ' ',
           Originating Server, ' ',
           Stream ID
         }
       )
 

Parameters:

originatingServer - the hostname of the Originating Server

receivingServer - the hostname of the Receiving Server

secret - a secret known by the Authoritative Server's network

streamID - the Stream ID generated by the Receiving Server

Returns:

string contains HEX encoded dialback key.

hexDigest

public static final String hexDigest(String id,
                                     String secret,
                                     String alg)
                              throws NoSuchAlgorithmException

This method encodes data using digest algorithm described in JEP-0078 documentation. As a result you have String containing digest data which can be compared with data sent by the user to authenticate him.

Parameters:

id - a String value of some ID value like session ID to concatenate with secret word.

secret - a String value of a secret word shared between entites.

alg - a String value of algorithm name to use for generating diffest message.

Returns:

a String value digest message as defined.

Throws:

NoSuchAlgorithmException - if an error occurs during encoding digest message.

sha256

public static String sha256(String data)

Calculates SHA-256 hash of given data.

Parameters:

data - data to hash

Returns:

string contains HEX encoded SHA-256 of data.