/*
* 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
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*/
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;
}
}