gnu.javax.crypto.mac
Class UHash32
 IMac
UHASH is a keyed hash function, which takes as input a string of
arbitrary length, and produces as output a string of fixed length (such as 8
bytes). The actual output length depends on the parameter UMACOUTPUTLEN.
UHASH has been shown to be epsilonASU ("Almost Strongly
Universal"), where epsilon is a small (parameterdependent) real number.
Informally, saying that a keyed hash function is epsilonASU means
that for any two distinct fixed input strings, the two outputs of the hash
function with a random key "look almost like a pair of random strings". The
number epsilon measures how nonrandom the output strings may be.
UHASH has been designed to be fast by exploiting several
architectural features of modern commodity processors. It was specifically
designed for use in UMAC. But UHASH is useful beyond that
domain, and can be easily adopted for other purposes.
UHASH does its work in three layers. First, a hash function called
NH
is used to compress input messages into strings which are
typically many times smaller than the input message. Second, the compressed
message is hashed with an optimized polynomial hash function into a
fixedlength 16byte string. Finally, the 16byte string is hashed using an
innerproduct hash into a string of length WORDLEN bytes. These
three layers are repeated (with a modified key) until the outputs total
UMACOUTPUTLEN bytes.
References:

UMAC: Message Authentication Code using Universal Hashing.
T. Krovetz, J. Black, S. Halevi, A. Hevia, H. Krawczyk, and P. Rogaway.
UHash32()  Trivial 0arguments constructor.

clone , equals , extends Object> getClass , finalize , hashCode , notify , notifyAll , toString , wait , wait , wait 
UHash32.java 
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