ojluni/src/main/java/sun/security/provider/DigestBase.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code 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
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 package sun.security.provider;

 import java.security.MessageDigestSpi;
 import java.security.DigestException;
 import java.security.ProviderException;

 /**
  * Common base message digest implementation for the Sun provider.
  * It implements all the JCA methods as suitable for a Java message digest
  * implementation of an algorithm based on a compression function (as all
  * commonly used algorithms are). The individual digest subclasses only need to
  * implement the following methods:
  *
  *  . abstract void implCompress(byte[] b, int ofs);
  *  . abstract void implDigest(byte[] out, int ofs);
  *  . abstract void implReset();
  *  . public abstract Object clone();
  *
  * See the inline documentation for details.
  *
  * @since   1.5
  * @author  Andreas Sterbenz
  */
 abstract class DigestBase extends MessageDigestSpi implements Cloneable {

     // one element byte array, temporary storage for update(byte)
     private byte[] oneByte;

     // algorithm name to use in the exception message
     private final String algorithm;
     // length of the message digest in bytes
     private final int digestLength;

     // size of the input to the compression function in bytes
     private final int blockSize;
     // buffer to store partial blocks, blockSize bytes large
     // Subclasses should not access this array directly except possibly in their
     // implDigest() method. See MD5.java as an example.
     final byte[] buffer;
     // offset into buffer
     private int bufOfs;

     // number of bytes processed so far. subclasses should not modify
     // this value.
     // also used as a flag to indicate reset status
     // -1: need to call engineReset() before next call to update()
     //  0: is already reset
     long bytesProcessed;

     /**
      * Main constructor.
      */
     DigestBase(String algorithm, int digestLength, int blockSize) {
         super();
         this.algorithm = algorithm;
         this.digestLength = digestLength;
         this.blockSize = blockSize;
         buffer = new byte[blockSize];
     }

     /**
      * Constructor for cloning. Replicates common data.
      */
     DigestBase(DigestBase base) {
         this.algorithm = base.algorithm;
         this.digestLength = base.digestLength;
         this.blockSize = base.blockSize;
         this.buffer = base.buffer.clone();
         this.bufOfs = base.bufOfs;
         this.bytesProcessed = base.bytesProcessed;
     }

     // return digest length. See JCA doc.
     protected final int engineGetDigestLength() {
         return digestLength;
     }

     // single byte update. See JCA doc.
     protected final void engineUpdate(byte b) {
         if (oneByte == null) {
             oneByte = new byte[1];
         }
         oneByte[0] = b;
         engineUpdate(oneByte, 0, 1);
     }

     // array update. See JCA doc.
     protected final void engineUpdate(byte[] b, int ofs, int len) {
         if (len == 0) {
             return;
         }
         if ((ofs < 0) || (len < 0) || (ofs > b.length - len)) {
             throw new ArrayIndexOutOfBoundsException();
         }
         if (bytesProcessed < 0) {
             engineReset();
         }
         bytesProcessed += len;
         // if buffer is not empty, we need to fill it before proceeding
         if (bufOfs != 0) {
             int n = Math.min(len, blockSize - bufOfs);
             System.arraycopy(b, ofs, buffer, bufOfs, n);
             bufOfs += n;
             ofs += n;
             len -= n;
             if (bufOfs >= blockSize) {
                 // compress completed block now
                 implCompress(buffer, 0);
                 bufOfs = 0;
             }
         }
         // compress complete blocks
         while (len >= blockSize) {
             implCompress(b, ofs);
             len -= blockSize;
             ofs += blockSize;
         }
         // copy remainder to buffer
         if (len > 0) {
             System.arraycopy(b, ofs, buffer, 0, len);
             bufOfs = len;
         }
     }

     // reset this object. See JCA doc.
     protected final void engineReset() {
         if (bytesProcessed == 0) {
             // already reset, ignore
             return;
         }
         implReset();
         bufOfs = 0;
         bytesProcessed = 0;
     }

     // return the digest. See JCA doc.
     protected final byte[] engineDigest() {
         byte[] b = new byte[digestLength];
         try {
             engineDigest(b, 0, b.length);
         } catch (DigestException e) {
             throw (ProviderException)
                 new ProviderException("Internal error").initCause(e);
         }
         return b;
     }

     // return the digest in the specified array. See JCA doc.
     protected final int engineDigest(byte[] out, int ofs, int len)
             throws DigestException {
         if (len < digestLength) {
             throw new DigestException("Length must be at least "
                 + digestLength + " for " + algorithm + "digests");
         }
         if ((ofs < 0) || (len < 0) || (ofs > out.length - len)) {
             throw new DigestException("Buffer too short to store digest");
         }
         if (bytesProcessed < 0) {
             engineReset();
         }
         implDigest(out, ofs);
         bytesProcessed = -1;
         return digestLength;
     }

     /**
      * Core compression function. Processes blockSize bytes at a time
      * and updates the state of this object.
      */
     abstract void implCompress(byte[] b, int ofs);

     /**
      * Return the digest. Subclasses do not need to reset() themselves,
      * DigestBase calls implReset() when necessary.
      */
     abstract void implDigest(byte[] out, int ofs);

     /**
      * Reset subclass specific state to their initial values. DigestBase
      * calls this method when necessary.
      */
     abstract void implReset();

     /**
      * Clone this digest. Should be implemented as "return new MyDigest(this)".
      * That constructor should first call "super(baseDigest)" and then copy
      * subclass specific data.
      */
     public abstract Object clone();

     // padding used for the MD5, and SHA-* message digests
     static final byte[] padding;

     static {
         // we need 128 byte padding for SHA-384/512
         // and an additional 8 bytes for the high 8 bytes of the 16
         // byte bit counter in SHA-384/512
         padding = new byte[136];
         padding[0] = (byte)0x80;
     }

 }
	/*
	* Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package sun.security.provider;

	import java.security.MessageDigestSpi;
	import java.security.DigestException;
	import java.security.ProviderException;

	/**
	* Common base message digest implementation for the Sun provider.
	* It implements all the JCA methods as suitable for a Java message digest
	* implementation of an algorithm based on a compression function (as all
	* commonly used algorithms are). The individual digest subclasses only need to
	* implement the following methods:
	*
	* . abstract void implCompress(byte[] b, int ofs);
	* . abstract void implDigest(byte[] out, int ofs);
	* . abstract void implReset();
	* . public abstract Object clone();
	*
	* See the inline documentation for details.
	*
	* @since 1.5
	* @author Andreas Sterbenz
	*/
	abstract class DigestBase extends MessageDigestSpi implements Cloneable {

	// one element byte array, temporary storage for update(byte)
	private byte[] oneByte;

	// algorithm name to use in the exception message
	private final String algorithm;
	// length of the message digest in bytes
	private final int digestLength;

	// size of the input to the compression function in bytes
	private final int blockSize;
	// buffer to store partial blocks, blockSize bytes large
	// Subclasses should not access this array directly except possibly in their
	// implDigest() method. See MD5.java as an example.
	final byte[] buffer;
	// offset into buffer
	private int bufOfs;

	// number of bytes processed so far. subclasses should not modify
	// this value.
	// also used as a flag to indicate reset status
	// -1: need to call engineReset() before next call to update()
	// 0: is already reset
	long bytesProcessed;

	/**
	* Main constructor.
	*/
	DigestBase(String algorithm, int digestLength, int blockSize) {
	super();
	this.algorithm = algorithm;
	this.digestLength = digestLength;
	this.blockSize = blockSize;
	buffer = new byte[blockSize];
	}

	/**
	* Constructor for cloning. Replicates common data.
	*/
	DigestBase(DigestBase base) {
	this.algorithm = base.algorithm;
	this.digestLength = base.digestLength;
	this.blockSize = base.blockSize;
	this.buffer = base.buffer.clone();
	this.bufOfs = base.bufOfs;
	this.bytesProcessed = base.bytesProcessed;
	}

	// return digest length. See JCA doc.
	protected final int engineGetDigestLength() {
	return digestLength;
	}

	// single byte update. See JCA doc.
	protected final void engineUpdate(byte b) {
	if (oneByte == null) {
	oneByte = new byte[1];
	}
	oneByte[0] = b;
	engineUpdate(oneByte, 0, 1);
	}

	// array update. See JCA doc.
	protected final void engineUpdate(byte[] b, int ofs, int len) {
	if (len == 0) {
	return;
	}
	if ((ofs < 0) \|\| (len < 0) \|\| (ofs > b.length - len)) {
	throw new ArrayIndexOutOfBoundsException();
	}
	if (bytesProcessed < 0) {
	engineReset();
	}
	bytesProcessed += len;
	// if buffer is not empty, we need to fill it before proceeding
	if (bufOfs != 0) {
	int n = Math.min(len, blockSize - bufOfs);
	System.arraycopy(b, ofs, buffer, bufOfs, n);
	bufOfs += n;
	ofs += n;
	len -= n;
	if (bufOfs >= blockSize) {
	// compress completed block now
	implCompress(buffer, 0);
	bufOfs = 0;
	}
	}
	// compress complete blocks
	while (len >= blockSize) {
	implCompress(b, ofs);
	len -= blockSize;
	ofs += blockSize;
	}
	// copy remainder to buffer
	if (len > 0) {
	System.arraycopy(b, ofs, buffer, 0, len);
	bufOfs = len;
	}
	}

	// reset this object. See JCA doc.
	protected final void engineReset() {
	if (bytesProcessed == 0) {
	// already reset, ignore
	return;
	}
	implReset();
	bufOfs = 0;
	bytesProcessed = 0;
	}

	// return the digest. See JCA doc.
	protected final byte[] engineDigest() {
	byte[] b = new byte[digestLength];
	try {
	engineDigest(b, 0, b.length);
	} catch (DigestException e) {
	throw (ProviderException)
	new ProviderException("Internal error").initCause(e);
	}
	return b;
	}

	// return the digest in the specified array. See JCA doc.
	protected final int engineDigest(byte[] out, int ofs, int len)
	throws DigestException {
	if (len < digestLength) {
	throw new DigestException("Length must be at least "
	+ digestLength + " for " + algorithm + "digests");
	}
	if ((ofs < 0) \|\| (len < 0) \|\| (ofs > out.length - len)) {
	throw new DigestException("Buffer too short to store digest");
	}
	if (bytesProcessed < 0) {
	engineReset();
	}
	implDigest(out, ofs);
	bytesProcessed = -1;
	return digestLength;
	}

	/**
	* Core compression function. Processes blockSize bytes at a time
	* and updates the state of this object.
	*/
	abstract void implCompress(byte[] b, int ofs);

	/**
	* Return the digest. Subclasses do not need to reset() themselves,
	* DigestBase calls implReset() when necessary.
	*/
	abstract void implDigest(byte[] out, int ofs);

	/**
	* Reset subclass specific state to their initial values. DigestBase
	* calls this method when necessary.
	*/
	abstract void implReset();

	/**
	* Clone this digest. Should be implemented as "return new MyDigest(this)".
	* That constructor should first call "super(baseDigest)" and then copy
	* subclass specific data.
	*/
	public abstract Object clone();

	// padding used for the MD5, and SHA-* message digests
	static final byte[] padding;

	static {
	// we need 128 byte padding for SHA-384/512
	// and an additional 8 bytes for the high 8 bytes of the 16
	// byte bit counter in SHA-384/512
	padding = new byte[136];
	padding[0] = (byte)0x80;
	}

	}