// $Id: MD5.java 54 2007-01-24 16:22:09Z tp $
package fr.cryptohash;
/**
* <p>This class implements the MD5 digest algorithm under the
* <code>Digest</code> API, using the <code>DigestEngine</code> class.
* MD5 is defined in RFC 1321.</p>
*
* <pre>
* ==========================(LICENSE BEGIN)============================
*
* Copyright (c) 2007 Projet RNRT SAPHIR
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* ===========================(LICENSE END)=============================
* </pre>
*
* @version $Revision: 54 $
* @author Thomas Pornin <thomas.pornin@cryptolog.com>
*/
public class MD5 extends MDHelper {
/**
* Create the object.
*/
public MD5()
{
super(true, 8);
}
private int[] currentVal, X;
/** @see Digest */
public Digest copy()
{
MD5 d = new MD5();
System.arraycopy(currentVal, 0, d.currentVal, 0,
currentVal.length);
return copyState(d);
}
/** @see Digest */
public int getDigestLength()
{
return 16;
}
/** @see Digest */
public int getBlockLength()
{
return 64;
}
/** @see DigestEngine */
protected void engineReset()
{
currentVal[0] = (int)0x67452301;
currentVal[1] = (int)0xEFCDAB89;
currentVal[2] = (int)0x98BADCFE;
currentVal[3] = (int)0x10325476;
}
/** @see DigestEngine */
protected void doPadding(byte[] output, int outputOffset)
{
makeMDPadding();
for (int i = 0; i < 4; i ++)
encodeLEInt(currentVal[i],
output, outputOffset + 4 * i);
}
/** @see DigestEngine */
protected void doInit()
{
currentVal = new int[4];
X = new int[16];
engineReset();
}
/**
* Perform a circular rotation by <code>n</code> to the left
* of the 32-bit word <code>x</code>. The <code>n</code>
* parameter must be between 1 and 31 (inclusive).
*
* @param x the value to rotate
* @param n the rotation count (between 1 and 31)
* @return the rotated value
*/
private static final int circularLeft(int x, int n)
{
return (x << n) | (x >>> (32 - n));
}
/**
* Encode the 32-bit word <code>val</code> into the array
* <code>buf</code> at offset <code>off</code>, in little-endian
* convention (least significant byte first).
*
* @param val the value to encode
* @param buf the destination buffer
* @param off the destination offset
*/
private static final void encodeLEInt(int val, byte[] buf, int off)
{
buf[off + 0] = (byte)val;
buf[off + 1] = (byte)(val >>> 8);
buf[off + 2] = (byte)(val >>> 16);
buf[off + 3] = (byte)(val >>> 24);
}
/**
* Decode a 32-bit little-endian word from the array <code>buf</code>
* at offset <code>off</code>.
*
* @param buf the source buffer
* @param off the source offset
* @return the decoded value
*/
private static final int decodeLEInt(byte[] buf, int off)
{
return (buf[off] & 0xFF)
| ((buf[off + 1] & 0xFF) << 8)
| ((buf[off + 2] & 0xFF) << 16)
| ((buf[off + 3] & 0xFF) << 24);
}
private static final int F(int X, int Y, int Z)
{
return (Y & X) | (Z & ~X);
}
private static final int G(int X, int Y, int Z)
{
return (X & Z) | (Y & ~Z);
}
private static final int H(int X, int Y, int Z)
{
return X ^ Y ^ Z;
}
private static final int I(int X, int Y, int Z)
{
return Y ^ (X | ~Z);
}
/** @see DigestEngine */
protected void processBlock(byte[] data)
{
int A = currentVal[0], B = currentVal[1];
int C = currentVal[2], D = currentVal[3];
for (int i = 0; i < 16; i ++)
X[i] = decodeLEInt(data, 4 * i);
A = B + circularLeft(A + F(B, C, D) + X[ 0] + 0xD76AA478, 7);
D = A + circularLeft(D + F(A, B, C) + X[ 1] + 0xE8C7B756, 12);
C = D + circularLeft(C + F(D, A, B) + X[ 2] + 0x242070DB, 17);
B = C + circularLeft(B + F(C, D, A) + X[ 3] + 0xC1BDCEEE, 22);
A = B + circularLeft(A + F(B, C, D) + X[ 4] + 0xF57C0FAF, 7);
D = A + circularLeft(D + F(A, B, C) + X[ 5] + 0x4787C62A, 12);
C = D + circularLeft(C + F(D, A, B) + X[ 6] + 0xA8304613, 17);
B = C + circularLeft(B + F(C, D, A) + X[ 7] + 0xFD469501, 22);
A = B + circularLeft(A + F(B, C, D) + X[ 8] + 0x698098D8, 7);
D = A + circularLeft(D + F(A, B, C) + X[ 9] + 0x8B44F7AF, 12);
C = D + circularLeft(C + F(D, A, B) + X[10] + 0xFFFF5BB1, 17);
B = C + circularLeft(B + F(C, D, A) + X[11] + 0x895CD7BE, 22);
A = B + circularLeft(A + F(B, C, D) + X[12] + 0x6B901122, 7);
D = A + circularLeft(D + F(A, B, C) + X[13] + 0xFD987193, 12);
C = D + circularLeft(C + F(D, A, B) + X[14] + 0xA679438E, 17);
B = C + circularLeft(B + F(C, D, A) + X[15] + 0x49B40821, 22);
A = B + circularLeft(A + G(B, C, D) + X[ 1] + 0xF61E2562, 5);
D = A + circularLeft(D + G(A, B, C) + X[ 6] + 0xC040B340, 9);
C = D + circularLeft(C + G(D, A, B) + X[11] + 0x265E5A51, 14);
B = C + circularLeft(B + G(C, D, A) + X[ 0] + 0xE9B6C7AA, 20);
A = B + circularLeft(A + G(B, C, D) + X[ 5] + 0xD62F105D, 5);
D = A + circularLeft(D + G(A, B, C) + X[10] + 0x02441453, 9);
C = D + circularLeft(C + G(D, A, B) + X[15] + 0xD8A1E681, 14);
B = C + circularLeft(B + G(C, D, A) + X[ 4] + 0xE7D3FBC8, 20);
A = B + circularLeft(A + G(B, C, D) + X[ 9] + 0x21E1CDE6, 5);
D = A + circularLeft(D + G(A, B, C) + X[14] + 0xC33707D6, 9);
C = D + circularLeft(C + G(D, A, B) + X[ 3] + 0xF4D50D87, 14);
B = C + circularLeft(B + G(C, D, A) + X[ 8] + 0x455A14ED, 20);
A = B + circularLeft(A + G(B, C, D) + X[13] + 0xA9E3E905, 5);
D = A + circularLeft(D + G(A, B, C) + X[ 2] + 0xFCEFA3F8, 9);
C = D + circularLeft(C + G(D, A, B) + X[ 7] + 0x676F02D9, 14);
B = C + circularLeft(B + G(C, D, A) + X[12] + 0x8D2A4C8A, 20);
A = B + circularLeft(A + H(B, C, D) + X[ 5] + 0xFFFA3942, 4);
D = A + circularLeft(D + H(A, B, C) + X[ 8] + 0x8771F681, 11);
C = D + circularLeft(C + H(D, A, B) + X[11] + 0x6D9D6122, 16);
B = C + circularLeft(B + H(C, D, A) + X[14] + 0xFDE5380C, 23);
A = B + circularLeft(A + H(B, C, D) + X[ 1] + 0xA4BEEA44, 4);
D = A + circularLeft(D + H(A, B, C) + X[ 4] + 0x4BDECFA9, 11);
C = D + circularLeft(C + H(D, A, B) + X[ 7] + 0xF6BB4B60, 16);
B = C + circularLeft(B + H(C, D, A) + X[10] + 0xBEBFBC70, 23);
A = B + circularLeft(A + H(B, C, D) + X[13] + 0x289B7EC6, 4);
D = A + circularLeft(D + H(A, B, C) + X[ 0] + 0xEAA127FA, 11);
C = D + circularLeft(C + H(D, A, B) + X[ 3] + 0xD4EF3085, 16);
B = C + circularLeft(B + H(C, D, A) + X[ 6] + 0x04881D05, 23);
A = B + circularLeft(A + H(B, C, D) + X[ 9] + 0xD9D4D039, 4);
D = A + circularLeft(D + H(A, B, C) + X[12] + 0xE6DB99E5, 11);
C = D + circularLeft(C + H(D, A, B) + X[15] + 0x1FA27CF8, 16);
B = C + circularLeft(B + H(C, D, A) + X[ 2] + 0xC4AC5665, 23);
A = B + circularLeft(A + I(B, C, D) + X[ 0] + 0xF4292244, 6);
D = A + circularLeft(D + I(A, B, C) + X[ 7] + 0x432AFF97, 10);
C = D + circularLeft(C + I(D, A, B) + X[14] + 0xAB9423A7, 15);
B = C + circularLeft(B + I(C, D, A) + X[ 5] + 0xFC93A039, 21);
A = B + circularLeft(A + I(B, C, D) + X[12] + 0x655B59C3, 6);
D = A + circularLeft(D + I(A, B, C) + X[ 3] + 0x8F0CCC92, 10);
C = D + circularLeft(C + I(D, A, B) + X[10] + 0xFFEFF47D, 15);
B = C + circularLeft(B + I(C, D, A) + X[ 1] + 0x85845DD1, 21);
A = B + circularLeft(A + I(B, C, D) + X[ 8] + 0x6FA87E4F, 6);
D = A + circularLeft(D + I(A, B, C) + X[15] + 0xFE2CE6E0, 10);
C = D + circularLeft(C + I(D, A, B) + X[ 6] + 0xA3014314, 15);
B = C + circularLeft(B + I(C, D, A) + X[13] + 0x4E0811A1, 21);
A = B + circularLeft(A + I(B, C, D) + X[ 4] + 0xF7537E82, 6);
D = A + circularLeft(D + I(A, B, C) + X[11] + 0xBD3AF235, 10);
C = D + circularLeft(C + I(D, A, B) + X[ 2] + 0x2AD7D2BB, 15);
B = C + circularLeft(B + I(C, D, A) + X[ 9] + 0xEB86D391, 21);
currentVal[0] += A;
currentVal[1] += B;
currentVal[2] += C;
currentVal[3] += D;
}
}