com.arxanfintech.common.crypto.core

Class ConcatKDFBytesGenerator

java.lang.Object

com.arxanfintech.common.crypto.core.ConcatKDFBytesGenerator

All Implemented Interfaces:

org.spongycastle.crypto.DerivationFunction, org.spongycastle.crypto.DigestDerivationFunction

public class ConcatKDFBytesGenerator
extends Object
implements org.spongycastle.crypto.DigestDerivationFunction

Basic KDF generator for derived keys and ivs as defined by NIST SP 800-56A.

Constructor Summary

Constructors

Modifier	Constructor and Description
	ConcatKDFBytesGenerator(org.spongycastle.crypto.Digest digest)
protected	ConcatKDFBytesGenerator(int counterStart, org.spongycastle.crypto.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.
org.spongycastle.crypto.Digest	getDigest() return the underlying digest.
void	init(org.spongycastle.crypto.DerivationParameters param)

Methods inherited from class java.lang.Object

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

Constructor Detail

ConcatKDFBytesGenerator

protected ConcatKDFBytesGenerator(int counterStart,
                                  org.spongycastle.crypto.Digest digest)

Construct a KDF Parameters generator.

Parameters:

counterStart - value of counter.

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

ConcatKDFBytesGenerator

public ConcatKDFBytesGenerator(org.spongycastle.crypto.Digest digest)

Method Detail

init

public void init(org.spongycastle.crypto.DerivationParameters param)

Specified by:

init in interface org.spongycastle.crypto.DerivationFunction

getDigest

public org.spongycastle.crypto.Digest getDigest()

return the underlying digest.

Specified by:

getDigest in interface org.spongycastle.crypto.DigestDerivationFunction

generateBytes

public int generateBytes(byte[] out,
                         int outOff,
                         int len)
                  throws org.spongycastle.crypto.DataLengthException,
                         IllegalArgumentException

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

Specified by:

generateBytes in interface org.spongycastle.crypto.DerivationFunction

Throws:

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

org.spongycastle.crypto.DataLengthException - if the out buffer is too small.