gnu.javax.crypto.mac
Class HMac
- Cloneable, IMac
The implementation of the
HMAC (Keyed-Hash Message Authentication
Code).
HMAC can be used in combination with any iterated cryptographic hash
function.
HMAC also uses a
secret key for calculation and
verification of the message authentication values. The main goals behind this
construction are:
- To use, without modifications, available hash functions. In particular,
hash functions that perform well in software, and for which code is freely
and widely available.
- To preserve the original performance of the hash function without
incurring a significant degradation.
- To use and handle keys in a simple way.
- To have a well understood cryptographic analysis of the strength of the
authentication mechanism based on reasonable assumptions on the underlying
hash function.
- To allow for easy replaceability of the underlying hash function in case
that faster or more secure hash functions are found or required.
References:
- RFC 2104HMAC:
Keyed-Hashing for Message Authentication.
H. Krawczyk, M. Bellare, and R. Canetti.
clone , equals , extends Object> getClass , finalize , hashCode , notify , notifyAll , toString , wait , wait , wait |
ipad
protected byte[] ipad
HMac
protected HMac(IMessageDigest underlyingHash)
Trivial constructor for use by concrete subclasses.
underlyingHash
- the underlying hash algorithm instance.
HMac.java --
Copyright (C) 2001, 2002, 2003, 2006 Free Software Foundation, Inc.
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