1 /*
2 * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.security.provider;
27
28 import java.security.*;
29
30 import static sun.security.provider.ByteArrayAccess.*;
31
32 /**
33 * The MD4 class is used to compute an MD4 message digest over a given
34 * buffer of bytes. It is an implementation of the RSA Data Security Inc
35 * MD4 algorithim as described in internet RFC 1320.
36 *
37 * <p>The MD4 algorithm is very weak and should not be used unless it is
38 * unavoidable. Therefore, it is not registered in our standard providers. To
39 * obtain an implementation, call the static getInstance() method in this
40 * class.
41 *
42 * @author Andreas Sterbenz
43 */
44 public final class MD4 extends DigestBase {
45
46 // state of this object
47 private int[] state;
48 // temporary buffer, used by implCompress()
49 private int[] x;
50
51 // rotation constants
52 private static final int S11 = 3;
53 private static final int S12 = 7;
54 private static final int S13 = 11;
55 private static final int S14 = 19;
56 private static final int S21 = 3;
57 private static final int S22 = 5;
58 private static final int S23 = 9;
59 private static final int S24 = 13;
60 private static final int S31 = 3;
61 private static final int S32 = 9;
62 private static final int S33 = 11;
63 private static final int S34 = 15;
64
65 private final static Provider md4Provider;
66
67 static {
68 md4Provider = new Provider("MD4Provider", 1.0d, "MD4 MessageDigest") {
69 private static final long serialVersionUID = -8850464997518327965L;
70 };
71 AccessController.doPrivileged(new PrivilegedAction<Void>() {
72 public Void run() {
73 md4Provider.put("MessageDigest.MD4", "sun.security.provider.MD4");
74 return null;
75 }
76 });
77 }
78
79 public static MessageDigest getInstance() {
80 try {
81 return MessageDigest.getInstance("MD4", md4Provider);
82 } catch (NoSuchAlgorithmException e) {
83 // should never occur
84 throw new ProviderException(e);
85 }
86 }
87
88 // Standard constructor, creates a new MD4 instance.
89 public MD4() {
90 super("MD4", 16, 64);
91 state = new int[4];
92 x = new int[16];
93 implReset();
94 }
95
96 // clone this object
97 public Object clone() throws CloneNotSupportedException {
98 MD4 copy = (MD4) super.clone();
99 copy.state = copy.state.clone();
100 copy.x = new int[16];
101 return copy;
102 }
103
104 /**
105 * Reset the state of this object.
106 */
107 void implReset() {
108 // Load magic initialization constants.
109 state[0] = 0x67452301;
110 state[1] = 0xefcdab89;
111 state[2] = 0x98badcfe;
112 state[3] = 0x10325476;
113 }
114
115 /**
116 * Perform the final computations, any buffered bytes are added
117 * to the digest, the count is added to the digest, and the resulting
118 * digest is stored.
119 */
120 void implDigest(byte[] out, int ofs) {
121 long bitsProcessed = bytesProcessed << 3;
122
123 int index = (int)bytesProcessed & 0x3f;
124 int padLen = (index < 56) ? (56 - index) : (120 - index);
125 engineUpdate(padding, 0, padLen);
126
127 i2bLittle4((int)bitsProcessed, buffer, 56);
128 i2bLittle4((int)(bitsProcessed >>> 32), buffer, 60);
129 implCompress(buffer, 0);
130
131 i2bLittle(state, 0, out, ofs, 16);
132 }
133
134 private static int FF(int a, int b, int c, int d, int x, int s) {
135 a += ((b & c) | ((~b) & d)) + x;
136 return ((a << s) | (a >>> (32 - s)));
137 }
138
139 private static int GG(int a, int b, int c, int d, int x, int s) {
140 a += ((b & c) | (b & d) | (c & d)) + x + 0x5a827999;
141 return ((a << s) | (a >>> (32 - s)));
142 }
143
144 private static int HH(int a, int b, int c, int d, int x, int s) {
145 a += ((b ^ c) ^ d) + x + 0x6ed9eba1;
146 return ((a << s) | (a >>> (32 - s)));
147 }
148
149 /**
150 * This is where the functions come together as the generic MD4
151 * transformation operation. It consumes sixteen
152 * bytes from the buffer, beginning at the specified offset.
153 */
154 void implCompress(byte[] buf, int ofs) {
155 b2iLittle64(buf, ofs, x);
156
157 int a = state[0];
158 int b = state[1];
159 int c = state[2];
160 int d = state[3];
161
162 /* Round 1 */
163 a = FF (a, b, c, d, x[ 0], S11); /* 1 */
164 d = FF (d, a, b, c, x[ 1], S12); /* 2 */
165 c = FF (c, d, a, b, x[ 2], S13); /* 3 */
166 b = FF (b, c, d, a, x[ 3], S14); /* 4 */
167 a = FF (a, b, c, d, x[ 4], S11); /* 5 */
168 d = FF (d, a, b, c, x[ 5], S12); /* 6 */
169 c = FF (c, d, a, b, x[ 6], S13); /* 7 */
170 b = FF (b, c, d, a, x[ 7], S14); /* 8 */
171 a = FF (a, b, c, d, x[ 8], S11); /* 9 */
172 d = FF (d, a, b, c, x[ 9], S12); /* 10 */
173 c = FF (c, d, a, b, x[10], S13); /* 11 */
174 b = FF (b, c, d, a, x[11], S14); /* 12 */
175 a = FF (a, b, c, d, x[12], S11); /* 13 */
176 d = FF (d, a, b, c, x[13], S12); /* 14 */
177 c = FF (c, d, a, b, x[14], S13); /* 15 */
178 b = FF (b, c, d, a, x[15], S14); /* 16 */
179
180 /* Round 2 */
181 a = GG (a, b, c, d, x[ 0], S21); /* 17 */
182 d = GG (d, a, b, c, x[ 4], S22); /* 18 */
183 c = GG (c, d, a, b, x[ 8], S23); /* 19 */
184 b = GG (b, c, d, a, x[12], S24); /* 20 */
185 a = GG (a, b, c, d, x[ 1], S21); /* 21 */
186 d = GG (d, a, b, c, x[ 5], S22); /* 22 */
187 c = GG (c, d, a, b, x[ 9], S23); /* 23 */
188 b = GG (b, c, d, a, x[13], S24); /* 24 */
189 a = GG (a, b, c, d, x[ 2], S21); /* 25 */
190 d = GG (d, a, b, c, x[ 6], S22); /* 26 */
191 c = GG (c, d, a, b, x[10], S23); /* 27 */
192 b = GG (b, c, d, a, x[14], S24); /* 28 */
193 a = GG (a, b, c, d, x[ 3], S21); /* 29 */
194 d = GG (d, a, b, c, x[ 7], S22); /* 30 */
195 c = GG (c, d, a, b, x[11], S23); /* 31 */
196 b = GG (b, c, d, a, x[15], S24); /* 32 */
197
198 /* Round 3 */
199 a = HH (a, b, c, d, x[ 0], S31); /* 33 */
200 d = HH (d, a, b, c, x[ 8], S32); /* 34 */
201 c = HH (c, d, a, b, x[ 4], S33); /* 35 */
202 b = HH (b, c, d, a, x[12], S34); /* 36 */
203 a = HH (a, b, c, d, x[ 2], S31); /* 37 */
204 d = HH (d, a, b, c, x[10], S32); /* 38 */
205 c = HH (c, d, a, b, x[ 6], S33); /* 39 */
206 b = HH (b, c, d, a, x[14], S34); /* 40 */
207 a = HH (a, b, c, d, x[ 1], S31); /* 41 */
208 d = HH (d, a, b, c, x[ 9], S32); /* 42 */
209 c = HH (c, d, a, b, x[ 5], S33); /* 43 */
210 b = HH (b, c, d, a, x[13], S34); /* 44 */
211 a = HH (a, b, c, d, x[ 3], S31); /* 45 */
212 d = HH (d, a, b, c, x[11], S32); /* 46 */
213 c = HH (c, d, a, b, x[ 7], S33); /* 47 */
214 b = HH (b, c, d, a, x[15], S34); /* 48 */
215
216 state[0] += a;
217 state[1] += b;
218 state[2] += c;
219 state[3] += d;
220 }
221
222 }