/* * Copyright (c) 2005, 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.*; import static sun.security.provider.ByteArrayAccess.*; /** * The MD4 class is used to compute an MD4 message digest over a given * buffer of bytes. It is an implementation of the RSA Data Security Inc * MD4 algorithim as described in internet RFC 1320. * * <p>The MD4 algorithm is very weak and should not be used unless it is * unavoidable. Therefore, it is not registered in our standard providers. To * obtain an implementation, call the static getInstance() method in this * class. * * @author      Andreas Sterbenz */public final class MD4 extends DigestBase {     // state of this object    private final int[] state;    // temporary buffer, used by implCompress()    private final int[] x;     // rotation constants    private static final int S11 = 3;    private static final int S12 = 7;    private static final int S13 = 11;    private static final int S14 = 19;    private static final int S21 = 3;    private static final int S22 = 5;    private static final int S23 = 9;    private static final int S24 = 13;    private static final int S31 = 3;    private static final int S32 = 9;    private static final int S33 = 11;    private static final int S34 = 15;     private final static Provider md4Provider;     static {        md4Provider = new Provider("MD4Provider", 1.0d, "MD4 MessageDigest") {};        AccessController.doPrivileged(new PrivilegedAction<Void>() {            public Void run() {                md4Provider.put("MessageDigest.MD4", "sun.security.provider.MD4");                return null;            }        });    }     public static MessageDigest getInstance() {        try {            return MessageDigest.getInstance("MD4", md4Provider);        } catch (NoSuchAlgorithmException e) {            // should never occur            throw new ProviderException(e);        }    }     // Standard constructor, creates a new MD4 instance.    public MD4() {        super("MD4", 16, 64);        state = new int[4];        x = new int[16];        implReset();    }     // Cloning constructor    private MD4(MD4 base) {        super(base);        this.state = base.state.clone();        this.x = new int[16];    }     // clone this object    public Object clone() {        return new MD4(this);    }     /**     * Reset the state of this object.     */    void implReset() {        // Load magic initialization constants.        state[0] = 0x67452301;        state[1] = 0xefcdab89;        state[2] = 0x98badcfe;        state[3] = 0x10325476;    }     /**     * Perform the final computations, any buffered bytes are added     * to the digest, the count is added to the digest, and the resulting     * digest is stored.     */    void implDigest(byte[] out, int ofs) {        long bitsProcessed = bytesProcessed << 3;         int index = (int)bytesProcessed & 0x3f;        int padLen = (index < 56) ? (56 - index) : (120 - index);        engineUpdate(padding, 0, padLen);         i2bLittle4((int)bitsProcessed, buffer, 56);        i2bLittle4((int)(bitsProcessed >>> 32), buffer, 60);        implCompress(buffer, 0);         i2bLittle(state, 0, out, ofs, 16);    }     private static int FF(int a, int b, int c, int d, int x, int s) {        a += ((b & c) | ((~b) & d)) + x;        return ((a << s) | (a >>> (32 - s)));    }     private static int GG(int a, int b, int c, int d, int x, int s) {        a += ((b & c) | (b & d) | (c & d)) + x + 0x5a827999;        return ((a << s) | (a >>> (32 - s)));    }     private static int HH(int a, int b, int c, int d, int x, int s) {        a += ((b ^ c) ^ d) + x + 0x6ed9eba1;        return ((a << s) | (a >>> (32 - s)));    }     /**     * This is where the functions come together as the generic MD4     * transformation operation. It consumes sixteen     * bytes from the buffer, beginning at the specified offset.     */    void implCompress(byte[] buf, int ofs) {        b2iLittle64(buf, ofs, x);         int a = state[0];        int b = state[1];        int c = state[2];        int d = state[3];         /* Round 1 */        a = FF (a, b, c, d, x[ 0], S11); /* 1 */        d = FF (d, a, b, c, x[ 1], S12); /* 2 */        c = FF (c, d, a, b, x[ 2], S13); /* 3 */        b = FF (b, c, d, a, x[ 3], S14); /* 4 */        a = FF (a, b, c, d, x[ 4], S11); /* 5 */        d = FF (d, a, b, c, x[ 5], S12); /* 6 */        c = FF (c, d, a, b, x[ 6], S13); /* 7 */        b = FF (b, c, d, a, x[ 7], S14); /* 8 */        a = FF (a, b, c, d, x[ 8], S11); /* 9 */        d = FF (d, a, b, c, x[ 9], S12); /* 10 */        c = FF (c, d, a, b, x[10], S13); /* 11 */        b = FF (b, c, d, a, x[11], S14); /* 12 */        a = FF (a, b, c, d, x[12], S11); /* 13 */        d = FF (d, a, b, c, x[13], S12); /* 14 */        c = FF (c, d, a, b, x[14], S13); /* 15 */        b = FF (b, c, d, a, x[15], S14); /* 16 */         /* Round 2 */        a = GG (a, b, c, d, x[ 0], S21); /* 17 */        d = GG (d, a, b, c, x[ 4], S22); /* 18 */        c = GG (c, d, a, b, x[ 8], S23); /* 19 */        b = GG (b, c, d, a, x[12], S24); /* 20 */        a = GG (a, b, c, d, x[ 1], S21); /* 21 */        d = GG (d, a, b, c, x[ 5], S22); /* 22 */        c = GG (c, d, a, b, x[ 9], S23); /* 23 */        b = GG (b, c, d, a, x[13], S24); /* 24 */        a = GG (a, b, c, d, x[ 2], S21); /* 25 */        d = GG (d, a, b, c, x[ 6], S22); /* 26 */        c = GG (c, d, a, b, x[10], S23); /* 27 */        b = GG (b, c, d, a, x[14], S24); /* 28 */        a = GG (a, b, c, d, x[ 3], S21); /* 29 */        d = GG (d, a, b, c, x[ 7], S22); /* 30 */        c = GG (c, d, a, b, x[11], S23); /* 31 */        b = GG (b, c, d, a, x[15], S24); /* 32 */         /* Round 3 */        a = HH (a, b, c, d, x[ 0], S31); /* 33 */        d = HH (d, a, b, c, x[ 8], S32); /* 34 */        c = HH (c, d, a, b, x[ 4], S33); /* 35 */        b = HH (b, c, d, a, x[12], S34); /* 36 */        a = HH (a, b, c, d, x[ 2], S31); /* 37 */        d = HH (d, a, b, c, x[10], S32); /* 38 */        c = HH (c, d, a, b, x[ 6], S33); /* 39 */        b = HH (b, c, d, a, x[14], S34); /* 40 */        a = HH (a, b, c, d, x[ 1], S31); /* 41 */        d = HH (d, a, b, c, x[ 9], S32); /* 42 */        c = HH (c, d, a, b, x[ 5], S33); /* 43 */        b = HH (b, c, d, a, x[13], S34); /* 44 */        a = HH (a, b, c, d, x[ 3], S31); /* 45 */        d = HH (d, a, b, c, x[11], S32); /* 46 */        c = HH (c, d, a, b, x[ 7], S33); /* 47 */        b = HH (b, c, d, a, x[15], S34); /* 48 */         state[0] += a;        state[1] += b;        state[2] += c;        state[3] += d;    } }