ivparameter.java

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/*
 *   
 *
 * Copyright  1990-2007 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
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 * 2 only, as published by the Free Software Foundation.
 * 
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License version 2 for more details (a copy is
 * included at /legal/license.txt).
 * 
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 * 02110-1301 USA
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 * NOTE:
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package com.sun.midp.crypto;

/**
 * This class specifies an <i>initialization vector</i> (IV).
 * Examples which use IVs are ciphers in feedback mode, e.g., DES in
 * CBC mode and RSA ciphers with OAEP encoding operation.
 */
public class IvParameter implements CryptoParameter {

    /** Initial vector. */
    private byte[] IV; // initial vector

    /**
     * Uses the first <code>len</code> bytes in <code>iv</code>,
     * beginning at <code>offset</code> inclusive, as the IV.
     *
     * <p> The bytes that constitute the IV are those between
     * <code>iv[offset]</code> and <code>iv[offset+len-1]</code> inclusive.
     *
     * @param iv the buffer with the IV
     * @param offset the offset in <code>iv</code> where the IV
     * starts
     * @param len the number of IV bytes
     */
    public IvParameter(byte[] iv, int offset, int len) {
        IV = Util.cloneSubarray(iv, offset, len);
    }

    /** 
     * Returns the initialization vector (IV).
     *
     * @return the initialization vector (IV)
     */
    public byte[] getIV() {
        return Util.cloneArray(IV);
    }
}