Back to index...

	/*
	* Copyright (c) 2006, 2021, 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.lang.invoke.MethodHandles;
	import java.lang.invoke.VarHandle;
	import java.nio.ByteOrder;

	/**
	* Optimized methods for converting between byte[] and int[]/long[], both for
	* big endian and little endian byte orders.
	*
	* NOTE that ArrayIndexOutOfBoundsException will be thrown if the bounds checks
	* failed.
	*
	* This class may also be helpful in improving the performance of the
	* crypto code in the SunJCE provider. However, for now it is only accessible by
	* the message digest implementation in the SUN provider.
	*
	* @since 1.6
	* @author Andreas Sterbenz
	*/
	final class ByteArrayAccess {

	private ByteArrayAccess() {
	// empty
	}

	static final class LE {
	static final VarHandle INT_ARRAY
	= MethodHandles.byteArrayViewVarHandle(int[].class,
	ByteOrder.LITTLE_ENDIAN).withInvokeExactBehavior();

	static final VarHandle LONG_ARRAY
	= MethodHandles.byteArrayViewVarHandle(long[].class,
	ByteOrder.LITTLE_ENDIAN).withInvokeExactBehavior();
	}

	static final class BE {
	static final VarHandle INT_ARRAY
	= MethodHandles.byteArrayViewVarHandle(int[].class,
	ByteOrder.BIG_ENDIAN).withInvokeExactBehavior();

	static final VarHandle LONG_ARRAY
	= MethodHandles.byteArrayViewVarHandle(long[].class,
	ByteOrder.BIG_ENDIAN).withInvokeExactBehavior();
	}

	/**
	* int[] to byte[] conversion, little endian byte order.
	*/
	static void i2bLittle(int[] in, int inOfs, byte[] out, int outOfs, int len) {
	len += outOfs;
	while (outOfs < len) {
	LE.INT_ARRAY.set(out, outOfs, in[inOfs++]);
	outOfs += 4;
	}
	}

	// Store one 32-bit value into out[outOfs..outOfs+3] in little endian order.
	static void i2bLittle4(int val, byte[] out, int outOfs) {
	LE.INT_ARRAY.set(out, outOfs, val);
	}

	/**
	* byte[] to int[] conversion, big endian byte order.
	*/
	static void b2iBig(byte[] in, int inOfs, int[] out, int outOfs, int len) {
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = (int) BE.INT_ARRAY.get(in, inOfs);
	inOfs += 4;
	}
	}

	// Special optimization of b2iBig(in, inOfs, out, 0, 64)
	static void b2iBig64(byte[] in, int inOfs, int[] out) {
	out[ 0] = (int) BE.INT_ARRAY.get(in, inOfs );
	out[ 1] = (int) BE.INT_ARRAY.get(in, inOfs + 4);
	out[ 2] = (int) BE.INT_ARRAY.get(in, inOfs + 8);
	out[ 3] = (int) BE.INT_ARRAY.get(in, inOfs + 12);
	out[ 4] = (int) BE.INT_ARRAY.get(in, inOfs + 16);
	out[ 5] = (int) BE.INT_ARRAY.get(in, inOfs + 20);
	out[ 6] = (int) BE.INT_ARRAY.get(in, inOfs + 24);
	out[ 7] = (int) BE.INT_ARRAY.get(in, inOfs + 28);
	out[ 8] = (int) BE.INT_ARRAY.get(in, inOfs + 32);
	out[ 9] = (int) BE.INT_ARRAY.get(in, inOfs + 36);
	out[10] = (int) BE.INT_ARRAY.get(in, inOfs + 40);
	out[11] = (int) BE.INT_ARRAY.get(in, inOfs + 44);
	out[12] = (int) BE.INT_ARRAY.get(in, inOfs + 48);
	out[13] = (int) BE.INT_ARRAY.get(in, inOfs + 52);
	out[14] = (int) BE.INT_ARRAY.get(in, inOfs + 56);
	out[15] = (int) BE.INT_ARRAY.get(in, inOfs + 60);
	}

	/**
	* int[] to byte[] conversion, big endian byte order.
	*/
	static void i2bBig(int[] in, int inOfs, byte[] out, int outOfs, int len) {
	len += outOfs;
	while (outOfs < len) {
	BE.INT_ARRAY.set(out, outOfs, in[inOfs++]);
	outOfs += 4;
	}
	}

	// Store one 32-bit value into out[outOfs..outOfs+3] in big endian order.
	static void i2bBig4(int val, byte[] out, int outOfs) {
	BE.INT_ARRAY.set(out, outOfs, val);
	}

	/**
	* byte[] to long[] conversion, big endian byte order.
	*/
	static void b2lBig(byte[] in, int inOfs, long[] out, int outOfs, int len) {
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = (long) BE.LONG_ARRAY.get(in, inOfs);
	inOfs += 8;
	}
	}

	// Special optimization of b2lBig(in, inOfs, out, 0, 128)
	static void b2lBig128(byte[] in, int inOfs, long[] out) {
	out[ 0] = (long) BE.LONG_ARRAY.get(in, inOfs );
	out[ 1] = (long) BE.LONG_ARRAY.get(in, inOfs + 8);
	out[ 2] = (long) BE.LONG_ARRAY.get(in, inOfs + 16);
	out[ 3] = (long) BE.LONG_ARRAY.get(in, inOfs + 24);
	out[ 4] = (long) BE.LONG_ARRAY.get(in, inOfs + 32);
	out[ 5] = (long) BE.LONG_ARRAY.get(in, inOfs + 40);
	out[ 6] = (long) BE.LONG_ARRAY.get(in, inOfs + 48);
	out[ 7] = (long) BE.LONG_ARRAY.get(in, inOfs + 56);
	out[ 8] = (long) BE.LONG_ARRAY.get(in, inOfs + 64);
	out[ 9] = (long) BE.LONG_ARRAY.get(in, inOfs + 72);
	out[10] = (long) BE.LONG_ARRAY.get(in, inOfs + 80);
	out[11] = (long) BE.LONG_ARRAY.get(in, inOfs + 88);
	out[12] = (long) BE.LONG_ARRAY.get(in, inOfs + 96);
	out[13] = (long) BE.LONG_ARRAY.get(in, inOfs + 104);
	out[14] = (long) BE.LONG_ARRAY.get(in, inOfs + 112);
	out[15] = (long) BE.LONG_ARRAY.get(in, inOfs + 120);
	}

	/**
	* long[] to byte[] conversion, big endian byte order.
	*/
	static void l2bBig(long[] in, int inOfs, byte[] out, int outOfs, int len) {
	len += outOfs;
	while (outOfs < len) {
	BE.LONG_ARRAY.set(out, outOfs, in[inOfs++]);
	outOfs += 8;
	}
	}

	/**
	* byte[] to long[] conversion, little endian byte order
	*/
	static void b2lLittle(byte[] in, int inOfs, long[] out, int outOfs, int len) {
	len += inOfs;
	while (inOfs < len) {
	out[outOfs++] = (long) LE.LONG_ARRAY.get(in, inOfs);
	inOfs += 8;
	}
	}


	/**
	* long[] to byte[] conversion, little endian byte order
	*/
	static void l2bLittle(long[] in, int inOfs, byte[] out, int outOfs, int len) {
	len += outOfs;
	while (outOfs < len) {
	LE.LONG_ARRAY.set(out, outOfs, in[inOfs++]);
	outOfs += 8;
	}
	}
	}

Back to index...