org.cryptacular.generator.sp80038a

Class BigIntegerCounterNonce

java.lang.Object

org.cryptacular.generator.sp80038a.BigIntegerCounterNonce

All Implemented Interfaces:

Nonce

public class BigIntegerCounterNonce
extends Object
implements Nonce

Uses a BigInteger to back a counter in order to produce nonces of arbitrary length.

A common use case for this component is creation of IVs for ciphers with 16-byte block size, e.g. AES.

Instances of this class are thread safe.

Author:

Middleware Services

Constructor Summary

Constructors

Constructor and Description
BigIntegerCounterNonce(BigInteger counter, int length) Creates a new instance with given parameters.

Method Summary

Modifier and Type	Method and Description
byte[]	generate() Generates a nonce value.
int	getLength()

Methods inherited from class java.lang.Object

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

Constructor Detail

BigIntegerCounterNonce

public BigIntegerCounterNonce(BigInteger counter,
                              int length)

Creates a new instance with given parameters.

Parameters:

counter - Initial counter value.

length - Maximum length of generated counter values in bytes.

Method Detail

generate

public byte[] generate()
                throws LimitException

Generates a nonce value.

Specified by:

generate in interface Nonce

Returns:

Nonce bytes.

Throws:

LimitException - When a limit imposed by the nonce generation strategy, if any, is exceeded.

getLength

public int getLength()

Specified by:

getLength in interface Nonce

Returns:

Length in bytes of generated nonce values.