ripemd160.java

一个非常好的ssh客户端实现

/******************************************************************************
 *
 * Copyright (c) 1999-2003 AppGate Network Security AB. All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code as
 * defined in and that are subject to the MindTerm Public Source License,
 * Version 2.0, (the 'License'). You may not use this file except in compliance
 * with the License.
 * 
 * You should have received a copy of the MindTerm Public Source License
 * along with this software; see the file LICENSE.  If not, write to
 * AppGate Network Security AB, Otterhallegatan 2, SE-41118 Goteborg, SWEDEN
 *
 *****************************************************************************/

package com.mindbright.security.digest;

import com.mindbright.jca.security.DigestException;

public final class RIPEMD160 extends MD512BitBlock {

    public static final int DIGEST_LENGTH = 20;

    private int[] x;
    private int[] hash;

    // selection of message word
    private final static int[] r1 = {
	0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
	7,  4, 13,  1, 10,  6, 15,  3, 12,  0,  9,  5,  2, 14, 11,  8,
	3, 10, 14,  4,  9, 15,  8,  1,  2,  7,  0,  6, 13, 11,  5, 12,
	1,  9, 11, 10,  0,  8, 12,  4, 13,  3,  7, 15, 14,  5,  6,  2,
	4,  0,  5,  9,  7, 12,  2, 10, 14,  1,  3,  8, 11,  6, 15, 13
    };
    private final static int[] r2 = {
	5, 14,  7,  0,  9,  2, 11,  4, 13,  6, 15,  8,  1, 10,  3, 12,
	6, 11,  3,  7,  0, 13,  5, 10, 14, 15,  8, 12,  4,  9,  1,  2,
	15,  5,  1,  3,  7, 14,  6,  9, 11,  8, 12,  2, 10,  0,  4, 13,
	8,  6,  4,  1,  3, 11, 15,  0,  5, 12,  2, 13,  9,  7, 10, 14,
	12, 15, 10,  4,  1,  5,  8,  7,  6,  2, 13, 14,  0,  3,  9, 11
    };
    
    // amount for rotate left (rol)
    private final static int[] s1  = {
	11, 14, 15, 12,  5,  8,  7,  9, 11, 13, 14, 15,  6,  7,  9,  8,
	7,  6,  8, 13, 11,  9,  7, 15,  7, 12, 15,  9, 11,  7, 13, 12,
	11, 13,  6,  7, 14,  9, 13, 15, 14,  8, 13,  6,  5, 12,  7,  5,
	11, 12, 14, 15, 14, 15,  9,  8,  9, 14,  5,  6,  8,  6,  5, 12,
	9, 15,  5, 11,  6,  8, 13, 12,  5, 12, 13, 14, 11,  8,  5,  6
    };
    private final static int[] s2 = {
	8,  9,  9, 11, 13, 15, 15,  5,  7,  7,  8, 11, 14, 14, 12,  6,
	9, 13, 15,  7, 12,  8,  9, 11,  7,  7, 12,  7,  6, 15, 13, 11,
	9,  7, 15, 11,  8,  6,  6, 14, 12, 13,  5, 14, 13, 13,  7,  5,
	15,  5,  8, 11, 14, 14,  6, 14,  6,  9, 12,  9, 12,  5, 15,  8,
	8,  5, 12,  9, 12,  5, 14,  6,  8, 13,  6,  5, 15, 13, 11, 11
    };

    private static int F00_15(int a, int b, int c, int d, int e, int x, int s) {
	a = a + (b ^ c ^ d) + x;
	return rotateLeft(a, s) + e;
    }

    private static int F16_31(int a, int b, int c, int d, int e,
			      int x, int s, int k) {
	a = a + ((b & c) | (~b & d)) + x + k;
	return rotateLeft(a, s) + e;
    }

    private static int F32_47(int a, int b, int c, int d, int e,
			      int x, int s, int k) {
	a = a + ((b | ~c) ^ d) + x + k;
	return rotateLeft(a, s) + e;
    }

    private static int F48_63(int a, int b, int c, int d, int e,
			      int x, int s, int k) {
	a = a + ((b & d) | (c & ~d)) + x + k;
	return rotateLeft(a, s) + e;
    }

    private static int F64_79(int a, int b, int c, int d, int e,
			      int x, int s, int k) {
	a = a + (b ^ (c | ~d)) + x + k;
	return rotateLeft(a, s) + e;
    }

    protected void transform(byte data[], int offset) {
	int a1, b1, c1, d1, e1, a2, b2, c2, d2, e2, t, i;

	a1 = a2 = hash[0];
	b1 = b2 = hash[1];
	c1 = c2 = hash[2];
	d1 = d2 = hash[3];
	e1 = e2 = hash[4];

	for (i = 0; i < 16; i++) {
	    x[i] =
		((((int) (data[offset++] & 0xff))      ) |
		 (((int) (data[offset++] & 0xff)) <<  8) |
		 (((int) (data[offset++] & 0xff)) << 16) |
		 (((int) (data[offset++] & 0xff)) << 24));
	}

        for (i = 0; i < 16; i++) {
            t = F00_15(a1, b1, c1, d1, e1, x[i], s1[i]);
            a1 = e1;
	    e1 = d1;
	    d1 = c1 << 10 | c1 >>> 22;
	    c1 = b1;
            b1 = t;

            t = F64_79(a2, b2, c2, d2, e2, x[r2[i]], s2[i], 0x50a28be6);
            a2 = e2;
	    e2 = d2;
	    d2 = c2 << 10 | c2 >>> 22;
	    c2 = b2;
            b2 = t;
        }

        for (i = 16; i < 32; i++) {
            t = F16_31(a1, b1, c1, d1, e1, x[r1[i]], s1[i], 0x5a827999);
            a1 = e1;
	    e1 = d1;
	    d1 = c1 << 10 | c1 >>> 22;
	    c1 = b1;
            b1 = t;

            t = F48_63(a2, b2, c2, d2, e2, x[r2[i]], s2[i], 0x5c4dd124);
            a2 = e2;
	    e2 = d2;
	    d2 = c2 << 10 | c2 >>> 22;
	    c2 = b2;
            b2 = t;
        }

        for (i = 32; i < 48; i++) {
            t = F32_47(a1, b1, c1, d1, e1, x[r1[i]], s1[i], 0x6ed9eba1);
            a1 = e1;
	    e1 = d1;
	    d1 = c1 << 10 | c1 >>> 22;
	    c1 = b1;
            b1 = t;

            t = F32_47(a2, b2, c2, d2, e2, x[r2[i]], s2[i], 0x6d703ef3);
            a2 = e2;
	    e2 = d2;
	    d2 = c2 << 10 | c2 >>> 22;
	    c2 = b2;
            b2 = t;
        }

        for (i = 48; i < 64; i++) {
            t = F48_63(a1, b1, c1, d1, e1, x[r1[i]], s1[i], 0x8f1bbcdc);
            a1 = e1;
	    e1 = d1;
	    d1 = c1 << 10 | c1 >>> 22;
	    c1 = b1;
            b1 = t;

            t = F16_31(a2, b2, c2, d2, e2, x[r2[i]], s2[i], 0x7a6d76e9);
            a2 = e2;
	    e2 = d2;
	    d2 = c2 << 10 | c2 >>> 22;
	    c2 = b2;
            b2 = t;
        }

        for (i = 64; i < 80; i++) {
            t = F64_79(a1, b1, c1, d1, e1, x[r1[i]], s1[i], 0xa953fd4e);
            a1 = e1;
	    e1 = d1;
	    d1 = c1 << 10 | c1 >>> 22;
	    c1 = b1;
            b1 = t;

            t = F00_15(a2, b2, c2, d2, e2, x[r2[i]], s2[i]);
            a2 = e2;
	    e2 = d2;
	    d2 = c2 << 10 | c2 >>> 22;
	    c2 = b2;
            b2 = t;
        }

	d2 += c1 + hash[1];
	hash[1] = hash[2] + d1 + e2;
	hash[2] = hash[3] + e1 + a2;
	hash[3] = hash[4] + a1 + b2;
	hash[4] = hash[0] + b1 + c2;
	hash[0] = d2;
    }

    public RIPEMD160() {
	super("RIPEMD160", DIGEST_LENGTH);
	hash = new int[5];
	x    = new int[16];
    }

    protected MD512BitBlock cloneInternal() {
	RIPEMD160 md = new RIPEMD160();

	md.hash[0] = this.hash[0];
	md.hash[1] = this.hash[1];
	md.hash[2] = this.hash[2];
	md.hash[3] = this.hash[3];
	md.hash[4] = this.hash[4];

	return md;
    }

    protected void engineReset() {
	hash[0] = 0x67452301;
	hash[1] = 0xefcdab89;
	hash[2] = 0x98badcfe;
	hash[3] = 0x10325476;
	hash[4] = 0xc3d2e1f0;
	count   = 0;
        rest    = 0;
    }

    protected int engineDigest(byte[] dest, int off, int len)
	throws DigestException
    {
	int padlen = (rest < 56) ? (56 - rest) : (120 - rest);

	if(len < DIGEST_LENGTH) {
	    throw new DigestException("RIPEMD160, output buffer too short");
	}

	count *= 8;
	byte[] countBytes = {
	    (byte)(count),
	    (byte)(count >>>  8),
	    (byte)(count >>> 16),
	    (byte)(count >>> 24),
	    (byte)(count >>> 32),
	    (byte)(count >>> 40),
	    (byte)(count >>> 58),
	    (byte)(count >>> 56)
	};

	engineUpdate(md4_padding, 0, padlen);
	engineUpdate(countBytes, 0, 8);

        int i, h;
        for (i = 0; i < 5; i++) {
	    h = hash[i];
            dest[off++] = (byte)((h       ) & 0xff);
            dest[off++] = (byte)((h >>>  8) & 0xff);
            dest[off++] = (byte)((h >>> 16) & 0xff);
            dest[off++] = (byte)((h >>> 24) & 0xff);
        }

	engineReset();

	return DIGEST_LENGTH;
    }

}