org.spongycastle.crypto.generators

Class BaseKDFBytesGenerator

java.lang.Object

org.spongycastle.crypto.generators.BaseKDFBytesGenerator

All Implemented Interfaces:

DerivationFunction, DigestDerivationFunction

Direct Known Subclasses:

KDF1BytesGenerator, KDF2BytesGenerator

public class BaseKDFBytesGenerator
extends java.lang.Object
implements DigestDerivationFunction

Basic KDF generator for derived keys and ivs as defined by IEEE P1363a/ISO 18033
This implementation is based on ISO 18033/P1363a.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BaseKDFBytesGenerator(int counterStart, Digest digest) Construct a KDF Parameters generator.

Method Summary

Modifier and Type	Method and Description
int	generateBytes(byte[] out, int outOff, int len) fill len bytes of the output buffer with bytes generated from the derivation function.
Digest	getDigest() return the underlying digest.
void	init(DerivationParameters param)

Methods inherited from class java.lang.Object

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

Constructor Detail

BaseKDFBytesGenerator

protected BaseKDFBytesGenerator(int counterStart,
                                Digest digest)

Construct a KDF Parameters generator.

Parameters:

counterStart - value of counter.

digest - the digest to be used as the source of derived keys.

Method Detail

init

public void init(DerivationParameters param)

Specified by:

init in interface DerivationFunction

getDigest

public Digest getDigest()

return the underlying digest.

Specified by:

getDigest in interface DigestDerivationFunction

generateBytes

public int generateBytes(byte[] out,
                         int outOff,
                         int len)
                  throws DataLengthException,
                         java.lang.IllegalArgumentException

fill len bytes of the output buffer with bytes generated from the derivation function.

Specified by:

generateBytes in interface DerivationFunction

Throws:

java.lang.IllegalArgumentException - if the size of the request will cause an overflow.

DataLengthException - if the out buffer is too small.