org.cryptacular.generator.sp80038d

Class RBGNonce

java.lang.Object

org.cryptacular.generator.sp80038d.RBGNonce

All Implemented Interfaces:

Nonce

public class RBGNonce
extends Object
implements Nonce

RBG-based nonce generation strategy that uses a RBG component to produce values for the invocation field as described in NIST SP-800-38D, section 8.2.2.

NOTE: users of this class are responsible for counting number of invocations and enforcing the constraints described in section 8.3; namely the following:

The total number of invocations of the authenticated encryption function shall not exceed 2³², including all IV lengths and all instances of the authenticated encryption function with the given key.

Instances of this class are thread safe.

Author:

Middleware Services

Constructor Summary

Constructors

Constructor and Description
RBGNonce() Creates a new instance that produces 12-bytes (96-bits) of random data; that is, the fixed field of the nonce is null.
RBGNonce(int randomLength) Creates a new instance that produces length bytes of random data; that is, the fixed field of the nonce is null.
RBGNonce(String fixed, int randomLength) Creates a new instance using the given fixed field value.

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

RBGNonce

public RBGNonce()

Creates a new instance that produces 12-bytes (96-bits) of random data; that is, the fixed field of the nonce is null.

RBGNonce

public RBGNonce(int randomLength)

Creates a new instance that produces length bytes of random data; that is, the fixed field of the nonce is null.

Parameters:

randomLength - Number of bytes in the random part of the nonce. MUST be at least 12.

RBGNonce

public RBGNonce(String fixed,
                int randomLength)

Creates a new instance using the given fixed field value.

Parameters:

fixed - User-defined fixed field value.

randomLength - Number of bytes in the random part of the nonce. MUST be at least 12.

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.