Source for javax.crypto.spec.IvParameterSpec

   1: /* IvParameterSpec.java -- A simple wrapper for initialization vectors.
   2:    Copyright (C) 2004  Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package javax.crypto.spec;
  40: 
  41: import java.security.spec.AlgorithmParameterSpec;
  42: 
  43: /**
  44:  * A wrapper for an initialization vector. An initialization vector is
  45:  * necessary for any cipher in any <i>feedback mode</i>, e.g. CBC.
  46:  *
  47:  * @author Casey Marshall (csm@gnu.org)
  48:  */
  49: public class IvParameterSpec implements AlgorithmParameterSpec
  50: {
  51: 
  52:   // Fields.
  53:   // ------------------------------------------------------------------------
  54: 
  55:   /** The IV. */
  56:   private byte[] iv;
  57: 
  58:   // Constructors.
  59:   // ------------------------------------------------------------------------
  60: 
  61:   /**
  62:    * Create a new initialization vector spec from an entire byte array.
  63:    *
  64:    * @param iv The IV bytes.
  65:    */
  66:   public IvParameterSpec(byte[] iv)
  67:   {
  68:     this(iv, 0, iv.length);
  69:   }
  70: 
  71:   /**
  72:    * Create a new initialization vector spec from part of a byte array.
  73:    *
  74:    * @param iv  The IV bytes.
  75:    * @param off The offset into the IV bytes.
  76:    * @param len The number of IV bytes.
  77:    */
  78:   public IvParameterSpec(byte[] iv, int off, int len)
  79:   {
  80:     this.iv = new byte[len];
  81:     System.arraycopy(iv, off, this.iv, 0, len);
  82:   }
  83: 
  84:   // Instance methods.
  85:   // ------------------------------------------------------------------------
  86: 
  87:   /**
  88:    * Returns the IV. This method does not copy the byte array.
  89:    *
  90:    * @return The IV.
  91:    */
  92:   public byte[] getIV()
  93:   {
  94:     return iv;
  95:   }
  96: }