xref: /freebsd/sys/kern/md4c.c (revision 1de7b4b805ddbf2429da511c053686ac4591ed89)
1 /* MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm
2  */
3 
4 /*-
5    Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
6 
7    License to copy and use this software is granted provided that it
8    is identified as the "RSA Data Security, Inc. MD4 Message-Digest
9    Algorithm" in all material mentioning or referencing this software
10    or this function.
11 
12    License is also granted to make and use derivative works provided
13    that such works are identified as "derived from the RSA Data
14    Security, Inc. MD4 Message-Digest Algorithm" in all material
15    mentioning or referencing the derived work.
16 
17    RSA Data Security, Inc. makes no representations concerning either
18    the merchantability of this software or the suitability of this
19    software for any particular purpose. It is provided "as is"
20    without express or implied warranty of any kind.
21 
22    These notices must be retained in any copies of any part of this
23    documentation and/or software.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/md4.h>
32 
33 typedef unsigned char *POINTER;
34 typedef u_int16_t UINT2;
35 typedef u_int32_t UINT4;
36 
37 #define PROTO_LIST(list) list
38 
39 /* Constants for MD4Transform routine.
40  */
41 #define S11 3
42 #define S12 7
43 #define S13 11
44 #define S14 19
45 #define S21 3
46 #define S22 5
47 #define S23 9
48 #define S24 13
49 #define S31 3
50 #define S32 9
51 #define S33 11
52 #define S34 15
53 
54 static void MD4Transform PROTO_LIST ((UINT4 [4], const unsigned char [64]));
55 static void Encode PROTO_LIST
56   ((unsigned char *, UINT4 *, unsigned int));
57 static void Decode PROTO_LIST
58   ((UINT4 *, const unsigned char *, unsigned int));
59 
60 static unsigned char PADDING[64] = {
61   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
62   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
63   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
64 };
65 
66 /* F, G and H are basic MD4 functions.
67  */
68 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
69 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
70 #define H(x, y, z) ((x) ^ (y) ^ (z))
71 
72 /* ROTATE_LEFT rotates x left n bits.
73  */
74 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
75 
76 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
77 /* Rotation is separate from addition to prevent recomputation */
78 #define FF(a, b, c, d, x, s) { \
79     (a) += F ((b), (c), (d)) + (x); \
80     (a) = ROTATE_LEFT ((a), (s)); \
81   }
82 #define GG(a, b, c, d, x, s) { \
83     (a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; \
84     (a) = ROTATE_LEFT ((a), (s)); \
85   }
86 #define HH(a, b, c, d, x, s) { \
87     (a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; \
88     (a) = ROTATE_LEFT ((a), (s)); \
89   }
90 
91 /* MD4 initialization. Begins an MD4 operation, writing a new context.
92  */
93 void
94 MD4Init(MD4_CTX *context)
95 {
96   context->count[0] = context->count[1] = 0;
97 
98   /* Load magic initialization constants.
99    */
100   context->state[0] = 0x67452301;
101   context->state[1] = 0xefcdab89;
102   context->state[2] = 0x98badcfe;
103   context->state[3] = 0x10325476;
104 }
105 
106 /* MD4 block update operation. Continues an MD4 message-digest
107      operation, processing another message block, and updating the
108      context.
109  */
110 void
111 MD4Update(MD4_CTX *context, const unsigned char *input,
112     unsigned int inputLen)
113 {
114   unsigned int i, index, partLen;
115 
116   /* Compute number of bytes mod 64 */
117   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
118   /* Update number of bits */
119   if ((context->count[0] += ((UINT4)inputLen << 3))
120       < ((UINT4)inputLen << 3))
121     context->count[1]++;
122   context->count[1] += ((UINT4)inputLen >> 29);
123 
124   partLen = 64 - index;
125   /* Transform as many times as possible.
126    */
127   if (inputLen >= partLen) {
128     bcopy(input, &context->buffer[index], partLen);
129     MD4Transform (context->state, context->buffer);
130 
131     for (i = partLen; i + 63 < inputLen; i += 64)
132       MD4Transform (context->state, &input[i]);
133 
134     index = 0;
135   }
136   else
137     i = 0;
138 
139   /* Buffer remaining input */
140   bcopy(&input[i], &context->buffer[index], inputLen-i);
141 }
142 
143 /* MD4 padding. */
144 void
145 MD4Pad(MD4_CTX *context)
146 {
147   unsigned char bits[8];
148   unsigned int index, padLen;
149 
150   /* Save number of bits */
151   Encode (bits, context->count, 8);
152 
153   /* Pad out to 56 mod 64.
154    */
155   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
156   padLen = (index < 56) ? (56 - index) : (120 - index);
157   MD4Update (context, PADDING, padLen);
158 
159   /* Append length (before padding) */
160   MD4Update (context, bits, 8);
161 }
162 
163 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
164      the message digest and zeroizing the context.
165  */
166 void
167 MD4Final(unsigned char digest[static 16], MD4_CTX *context)
168 {
169   /* Do padding */
170   MD4Pad (context);
171 
172   /* Store state in digest */
173   Encode (digest, context->state, 16);
174 
175   /* Zeroize sensitive information.
176    */
177   bzero(context, sizeof (*context));
178 }
179 
180 /* MD4 basic transformation. Transforms state based on block.
181  */
182 static void
183 MD4Transform(UINT4 state[4], const unsigned char block[64])
184 {
185   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
186 
187   Decode (x, block, 64);
188 
189   /* Round 1 */
190   FF (a, b, c, d, x[ 0], S11); /* 1 */
191   FF (d, a, b, c, x[ 1], S12); /* 2 */
192   FF (c, d, a, b, x[ 2], S13); /* 3 */
193   FF (b, c, d, a, x[ 3], S14); /* 4 */
194   FF (a, b, c, d, x[ 4], S11); /* 5 */
195   FF (d, a, b, c, x[ 5], S12); /* 6 */
196   FF (c, d, a, b, x[ 6], S13); /* 7 */
197   FF (b, c, d, a, x[ 7], S14); /* 8 */
198   FF (a, b, c, d, x[ 8], S11); /* 9 */
199   FF (d, a, b, c, x[ 9], S12); /* 10 */
200   FF (c, d, a, b, x[10], S13); /* 11 */
201   FF (b, c, d, a, x[11], S14); /* 12 */
202   FF (a, b, c, d, x[12], S11); /* 13 */
203   FF (d, a, b, c, x[13], S12); /* 14 */
204   FF (c, d, a, b, x[14], S13); /* 15 */
205   FF (b, c, d, a, x[15], S14); /* 16 */
206 
207   /* Round 2 */
208   GG (a, b, c, d, x[ 0], S21); /* 17 */
209   GG (d, a, b, c, x[ 4], S22); /* 18 */
210   GG (c, d, a, b, x[ 8], S23); /* 19 */
211   GG (b, c, d, a, x[12], S24); /* 20 */
212   GG (a, b, c, d, x[ 1], S21); /* 21 */
213   GG (d, a, b, c, x[ 5], S22); /* 22 */
214   GG (c, d, a, b, x[ 9], S23); /* 23 */
215   GG (b, c, d, a, x[13], S24); /* 24 */
216   GG (a, b, c, d, x[ 2], S21); /* 25 */
217   GG (d, a, b, c, x[ 6], S22); /* 26 */
218   GG (c, d, a, b, x[10], S23); /* 27 */
219   GG (b, c, d, a, x[14], S24); /* 28 */
220   GG (a, b, c, d, x[ 3], S21); /* 29 */
221   GG (d, a, b, c, x[ 7], S22); /* 30 */
222   GG (c, d, a, b, x[11], S23); /* 31 */
223   GG (b, c, d, a, x[15], S24); /* 32 */
224 
225   /* Round 3 */
226   HH (a, b, c, d, x[ 0], S31); /* 33 */
227   HH (d, a, b, c, x[ 8], S32); /* 34 */
228   HH (c, d, a, b, x[ 4], S33); /* 35 */
229   HH (b, c, d, a, x[12], S34); /* 36 */
230   HH (a, b, c, d, x[ 2], S31); /* 37 */
231   HH (d, a, b, c, x[10], S32); /* 38 */
232   HH (c, d, a, b, x[ 6], S33); /* 39 */
233   HH (b, c, d, a, x[14], S34); /* 40 */
234   HH (a, b, c, d, x[ 1], S31); /* 41 */
235   HH (d, a, b, c, x[ 9], S32); /* 42 */
236   HH (c, d, a, b, x[ 5], S33); /* 43 */
237   HH (b, c, d, a, x[13], S34); /* 44 */
238   HH (a, b, c, d, x[ 3], S31); /* 45 */
239   HH (d, a, b, c, x[11], S32); /* 46 */
240   HH (c, d, a, b, x[ 7], S33); /* 47 */
241   HH (b, c, d, a, x[15], S34); /* 48 */
242 
243   state[0] += a;
244   state[1] += b;
245   state[2] += c;
246   state[3] += d;
247 
248   /* Zeroize sensitive information.
249    */
250   bzero((POINTER)x, sizeof (x));
251 }
252 
253 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
254      a multiple of 4.
255  */
256 static void
257 Encode(unsigned char *output, UINT4 *input, unsigned int len)
258 {
259   unsigned int i, j;
260 
261   for (i = 0, j = 0; j < len; i++, j += 4) {
262     output[j] = (unsigned char)(input[i] & 0xff);
263     output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
264     output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
265     output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
266   }
267 }
268 
269 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
270      a multiple of 4.
271  */
272 static void
273 Decode(UINT4 *output, const unsigned char *input, unsigned int len)
274 {
275   unsigned int i, j;
276 
277   for (i = 0, j = 0; j < len; i++, j += 4)
278     output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
279       (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
280 }
281