gnu.javax.crypto.prng
Class UMacGenerator
 Cloneable, IRandom
KDFs (Key Derivation Functions) are used to stretch usersupplied key
material to specific size(s) required by high level cryptographic primitives.
Described in the
UMAC
paper, this function basically operates an underlying
symmetric key block
cipher instance in output feedback mode (OFB), as a
strong
pseudorandom number generator.
UMacGenerator
requires an index parameter
(initialisation parameter gnu.crypto.prng.umac.kdf.index
taken
to be an instance of Integer
with a value between 0
and
255
). Using the same key, but different indices, generates
different pseudorandom outputs.
This implementation generalises the definition of the
UmacGenerator
algorithm to allow for other than the AES
symetric key block cipher algorithm (initialisation parameter
gnu.crypto.prng.umac.cipher.name
taken to be an instance of
String
). If such a parameter is not defined/included in the
initialisation Map
, then the "Rijndael" algorithm is used.
Furthermore, if the initialisation parameter
gnu.crypto.cipher.block.size
(taken to be a instance of
Integer
) is missing or undefined in the initialisation
Map
, then the cipher's default block size is used.
NOTE: Rijndael is used as the default symmetric key block cipher
algorithm because, with its default block and key sizes, it is the AES. Yet
being Rijndael, the algorithm offers more versatile block and key sizes which
may prove to be useful for generating "longer" key streams.
References:

UMAC: Message Authentication Code using Universal Hashing.
T. Krovetz, J. Black, S. Halevi, A. Hevia, H. Krawczyk, and P. Rogaway.
static String  CIPHER  The name of the underlying symmetric key block cipher algorithm.

static String  INDEX  Property name of the KDF
index value to use in this
instance.

addRandomByte , addRandomBytes , addRandomBytes , clone , fillBlock , init , isInitialised , name , nextByte , nextBytes , nextBytes , setup 
clone , equals , extends Object> getClass , finalize , hashCode , notify , notifyAll , toString , wait , wait , wait 
UMacGenerator.java 
Copyright (C) 2001, 2002, 2006 Free Software Foundation, Inc.
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