/*
 * 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
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/*
 *  (C) Copyright IBM Corp. 1999 All Rights Reserved.
 *  Copyright 1997 The Open Group Research Institute.  All rights reserved.
 */
// crc32.java

package sun.security.krb5.internal.crypto;

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

public final class crc32 extends MessageDigestSpi implements Cloneable {
    private static final int CRC32_LENGTH = 4; //32-bit
    private int seed;
    private static boolean DEBUG = sun.security.krb5.internal.Krb5.DEBUG;
    // buffer;
    // private int bufferIndex, bufferLeft;

    public crc32() {
        init();
    }

    public Object clone() {
        try {
            crc32 crc = (crc32)super.clone();
            crc.init();
            return crc;
        }
        catch (CloneNotSupportedException e) {
        }
        return null;
    }

    
Return the digest length in bytes
/** * Return the digest length in bytes */
protected int engineGetDigestLength() { return (CRC32_LENGTH); } /** */ protected byte[] engineDigest() { byte[] result = new byte[CRC32_LENGTH]; result = int2quad(seed); //processBuffer(buffer, 0, bufferIndex, result, 0); init(); return result; } /** */ protected int engineDigest(byte[] buf, int offset, int len) throws DigestException { byte[] result = new byte[CRC32_LENGTH]; result = int2quad(seed); if (len < CRC32_LENGTH) { throw new DigestException("partial digests not returned"); } if (buf.length - offset < CRC32_LENGTH) { throw new DigestException("insufficient space in the output " + "buffer to store the digest"); } System.arraycopy(result, 0, buf, offset, CRC32_LENGTH); //processBuffer(buffer, 0, bufferIndex, result, 0); /*if (len < CRC32_LENGTH) { throw new DigestException("partial digests not returned"); } if (buf.length - offset < CRC32_LENGTH) { throw new DigestException("insufficient space in the output " + "buffer to store the digest"); } System.arraycopy(result, 0, buf, offset, CRC32_LENGTH); */ init(); return CRC32_LENGTH; }
Update adds the passed byte to the digested data.
/** * Update adds the passed byte to the digested data. */
protected synchronized void engineUpdate(byte b) { byte[] input = new byte[1]; input[0] = b; //engineUpdate(input, 0, 1); engineUpdate(input, seed, 1); }
Update adds the selected part of an array of bytes to the digest. This version is more efficient than the byte-at-a-time version; it avoids data copies and reduces per-byte call overhead.
/** * Update adds the selected part of an array of bytes to the digest. * This version is more efficient than the byte-at-a-time version; * it avoids data copies and reduces per-byte call overhead. */
protected synchronized void engineUpdate(byte[] input, int offset, int len) { processData(input, offset, len); } private static int[] crc32Table = { 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d }; protected void engineReset() { init(); }
Initialize the CRC32 information
/** * Initialize the CRC32 information */
public void init() { seed = 0; } private void processData(byte[] data, int off, int len) { int result = seed; for (int i = 0; i < len; i++) result = (result >>> 8) ^ crc32Table[(result ^ data[i]) & 0xff]; seed = result; } public static int int2crc32(int b) { int crc = b; for (int i = 8; i > 0; i--) { if ((crc & 1) != 0) crc = (crc >>> 1) ^ 0xedb88320; else crc = crc >>> 1; } return crc; } public static void printcrc32Table() { String temp; String zerofill = "00000000"; System.out.print("\tpublic static int[] crc32Table = {"); for (int i = 0; i < 256; i++) { if ((i % 4) == 0) System.out.print("\n\t\t"); temp = Integer.toHexString(int2crc32(i)); System.out.print("0x" + zerofill.substring(temp.length()) + temp); if (i != 255) System.out.print(", "); } System.out.println("\n\t};"); } public static int byte2crc32sum(int seed, byte[] data, int size) { int crc = seed; for (int i = 0; i < size; i++) crc = (crc >>> 8) ^ crc32Table[(crc ^ data[i]) & 0xff]; return crc; } public static int byte2crc32sum(int seed, byte[] data) { return byte2crc32sum(seed, data, data.length); } //sum from zero, i.e., no pre- or post-conditioning public static int byte2crc32sum(byte[] data) { return byte2crc32sum(0, data); } //CCITT ITU-T 3309 CRC-32 w/ standard pre- and post-conditioning public static int byte2crc32(byte[] data) { return ~byte2crc32sum(0xffffffff, data); } public static byte[] byte2crc32sum_bytes(byte[] data) { int temp = byte2crc32sum(data); return int2quad(temp); } public static byte[] byte2crc32sum_bytes(byte[] data, int size) { int temp = byte2crc32sum(0, data, size); if (DEBUG) { System.out.println(">>>crc32: " + Integer.toHexString(temp)); System.out.println(">>>crc32: " + Integer.toBinaryString(temp)); } return int2quad(temp); } public static byte[] int2quad(long input) { byte[] output = new byte[4]; for (int i = 0; i < 4; i++) { output[i] = (byte)((input >>> (i * 8)) & 0xff); } return output; } }