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diff --git a/gcc-4.4.3/libjava/classpath/gnu/javax/crypto/mode/CBC.java b/gcc-4.4.3/libjava/classpath/gnu/javax/crypto/mode/CBC.java
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+/* CBC.java -- 
+   Copyright (C) 2002, 2006 Free Software Foundation, Inc.
+
+This file is a part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or (at
+your option) any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
+USA
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version.  */
+
+
+package gnu.javax.crypto.mode;
+
+import gnu.java.security.Registry;
+import gnu.javax.crypto.cipher.IBlockCipher;
+
+/**
+ * The Cipher Block Chaining mode. This mode introduces feedback into the cipher
+ * by XORing the previous ciphertext block with the plaintext block before
+ * encipherment. That is, encrypting looks like this:
+ * 
+ * <pre>
+ *  C<sub>i</sub> = E<sub>K</sub>(P<sub>i</sub>&circ; C<sub>i-1</sub>)
+ * </pre>
+ * <p>
+ * Similarly, decrypting is:
+ * <pre>
+ *  P<sub>i</sub> = C<sub>i-1</sub> &circ; D<sub>K</sub>(C<sub>i</sub>)
+ * </pre>
+ */
+public class CBC
+    extends BaseMode
+    implements Cloneable
+{
+  /** The last (de|en)crypted block */
+  private byte[] lastBlock;
+  /** An intermediate buffer. */
+  private byte[] scratch;
+
+  /**
+   * Package-private constructor for the factory class.
+   * 
+   * @param underlyingCipher The cipher implementation.
+   * @param cipherBlockSize The cipher's block size.
+   */
+  CBC(IBlockCipher underlyingCipher, int cipherBlockSize)
+  {
+    super(Registry.CBC_MODE, underlyingCipher, cipherBlockSize);
+  }
+
+  /** Our constructor for cloning. */
+  private CBC(CBC that)
+  {
+    this((IBlockCipher) that.cipher.clone(), that.cipherBlockSize);
+  }
+
+  public Object clone()
+  {
+    return new CBC(this);
+  }
+
+  public void setup()
+  {
+    if (modeBlockSize != cipherBlockSize)
+      throw new IllegalArgumentException();
+    scratch = new byte[cipherBlockSize];
+    lastBlock = new byte[cipherBlockSize];
+    // lastBlock gets initialized to the initialization vector.
+    for (int i = 0; i < lastBlock.length && i < iv.length; i++)
+      lastBlock[i] = iv[i];
+  }
+
+  public void teardown()
+  {
+    lastBlock = null;
+    scratch = null;
+  }
+
+  public void encryptBlock(byte[] in, int i, byte[] out, int o)
+  {
+    for (int k = 0; k < scratch.length; k++)
+      scratch[k] = (byte)(lastBlock[k] ^ in[k + i]);
+    cipher.encryptBlock(scratch, 0, out, o);
+    System.arraycopy(out, o, lastBlock, 0, cipherBlockSize);
+  }
+
+  public void decryptBlock(byte[] in, int i, byte[] out, int o)
+  {
+    byte[] buf = new byte[cipherBlockSize];
+    System.arraycopy(in, i, buf, 0, cipherBlockSize);
+    cipher.decryptBlock(in, i, scratch, 0);
+    for (int k = 0; k < scratch.length; k++)
+      out[o + k] = (byte)(lastBlock[k] ^ scratch[k]);
+    System.arraycopy(buf, 0, lastBlock, 0, cipherBlockSize);
+  }
+}