xref: /freebsd/sys/kern/md4c.c (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
1 /* MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm
2  */
3 
4 /*-
5    SPDX-License-Identifier: RSA-MD
6 
7    Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
8 
9    License to copy and use this software is granted provided that it
10    is identified as the "RSA Data Security, Inc. MD4 Message-Digest
11    Algorithm" in all material mentioning or referencing this software
12    or this function.
13 
14    License is also granted to make and use derivative works provided
15    that such works are identified as "derived from the RSA Data
16    Security, Inc. MD4 Message-Digest Algorithm" in all material
17    mentioning or referencing the derived work.
18 
19    RSA Data Security, Inc. makes no representations concerning either
20    the merchantability of this software or the suitability of this
21    software for any particular purpose. It is provided "as is"
22    without express or implied warranty of any kind.
23 
24    These notices must be retained in any copies of any part of this
25    documentation and/or software.
26  */
27 
28 #include <sys/param.h>
29 #ifdef _KERNEL
30 #include <sys/systm.h>
31 #else
32 #include <string.h>
33 #endif
34 #include <sys/md4.h>
35 
36 typedef unsigned char *POINTER;
37 typedef uint16_t UINT2;
38 typedef uint32_t UINT4;
39 
40 #define PROTO_LIST(list) list
41 
42 /* Constants for MD4Transform routine.
43  */
44 #define S11 3
45 #define S12 7
46 #define S13 11
47 #define S14 19
48 #define S21 3
49 #define S22 5
50 #define S23 9
51 #define S24 13
52 #define S31 3
53 #define S32 9
54 #define S33 11
55 #define S34 15
56 
57 static void MD4Transform PROTO_LIST ((UINT4 [4], const unsigned char [64]));
58 static void Encode PROTO_LIST
59   ((unsigned char *, UINT4 *, unsigned int));
60 static void Decode PROTO_LIST
61   ((UINT4 *, const unsigned char *, unsigned int));
62 
63 static unsigned char PADDING[64] = {
64   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
65   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
66   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
67 };
68 
69 /* F, G and H are basic MD4 functions.
70  */
71 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
72 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
73 #define H(x, y, z) ((x) ^ (y) ^ (z))
74 
75 /* ROTATE_LEFT rotates x left n bits.
76  */
77 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
78 
79 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
80 /* Rotation is separate from addition to prevent recomputation */
81 #define FF(a, b, c, d, x, s) { \
82     (a) += F ((b), (c), (d)) + (x); \
83     (a) = ROTATE_LEFT ((a), (s)); \
84   }
85 #define GG(a, b, c, d, x, s) { \
86     (a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; \
87     (a) = ROTATE_LEFT ((a), (s)); \
88   }
89 #define HH(a, b, c, d, x, s) { \
90     (a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; \
91     (a) = ROTATE_LEFT ((a), (s)); \
92   }
93 
94 /* MD4 initialization. Begins an MD4 operation, writing a new context.
95  */
96 void
97 MD4Init(MD4_CTX *context)
98 {
99   context->count[0] = context->count[1] = 0;
100 
101   /* Load magic initialization constants.
102    */
103   context->state[0] = 0x67452301;
104   context->state[1] = 0xefcdab89;
105   context->state[2] = 0x98badcfe;
106   context->state[3] = 0x10325476;
107 }
108 
109 /* MD4 block update operation. Continues an MD4 message-digest
110      operation, processing another message block, and updating the
111      context.
112  */
113 void
114 MD4Update(MD4_CTX *context, const unsigned char *input,
115     unsigned int inputLen)
116 {
117   unsigned int i, index, partLen;
118 
119   /* Compute number of bytes mod 64 */
120   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
121   /* Update number of bits */
122   if ((context->count[0] += ((UINT4)inputLen << 3))
123       < ((UINT4)inputLen << 3))
124     context->count[1]++;
125   context->count[1] += ((UINT4)inputLen >> 29);
126 
127   partLen = 64 - index;
128   /* Transform as many times as possible.
129    */
130   if (inputLen >= partLen) {
131     bcopy(input, &context->buffer[index], partLen);
132     MD4Transform (context->state, context->buffer);
133 
134     for (i = partLen; i + 63 < inputLen; i += 64)
135       MD4Transform (context->state, &input[i]);
136 
137     index = 0;
138   }
139   else
140     i = 0;
141 
142   /* Buffer remaining input */
143   bcopy(&input[i], &context->buffer[index], inputLen-i);
144 }
145 
146 /* MD4 padding. */
147 void
148 MD4Pad(MD4_CTX *context)
149 {
150   unsigned char bits[8];
151   unsigned int index, padLen;
152 
153   /* Save number of bits */
154   Encode (bits, context->count, 8);
155 
156   /* Pad out to 56 mod 64.
157    */
158   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
159   padLen = (index < 56) ? (56 - index) : (120 - index);
160   MD4Update (context, PADDING, padLen);
161 
162   /* Append length (before padding) */
163   MD4Update (context, bits, 8);
164 }
165 
166 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
167      the message digest and zeroizing the context.
168  */
169 void
170 MD4Final(unsigned char digest[static 16], MD4_CTX *context)
171 {
172   /* Do padding */
173   MD4Pad (context);
174 
175   /* Store state in digest */
176   Encode (digest, context->state, 16);
177 
178   /* Zeroize sensitive information.
179    */
180   bzero(context, sizeof (*context));
181 }
182 
183 /* MD4 basic transformation. Transforms state based on block.
184  */
185 static void
186 MD4Transform(UINT4 state[4], const unsigned char block[64])
187 {
188   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
189 
190   Decode (x, block, 64);
191 
192   /* Round 1 */
193   FF (a, b, c, d, x[ 0], S11); /* 1 */
194   FF (d, a, b, c, x[ 1], S12); /* 2 */
195   FF (c, d, a, b, x[ 2], S13); /* 3 */
196   FF (b, c, d, a, x[ 3], S14); /* 4 */
197   FF (a, b, c, d, x[ 4], S11); /* 5 */
198   FF (d, a, b, c, x[ 5], S12); /* 6 */
199   FF (c, d, a, b, x[ 6], S13); /* 7 */
200   FF (b, c, d, a, x[ 7], S14); /* 8 */
201   FF (a, b, c, d, x[ 8], S11); /* 9 */
202   FF (d, a, b, c, x[ 9], S12); /* 10 */
203   FF (c, d, a, b, x[10], S13); /* 11 */
204   FF (b, c, d, a, x[11], S14); /* 12 */
205   FF (a, b, c, d, x[12], S11); /* 13 */
206   FF (d, a, b, c, x[13], S12); /* 14 */
207   FF (c, d, a, b, x[14], S13); /* 15 */
208   FF (b, c, d, a, x[15], S14); /* 16 */
209 
210   /* Round 2 */
211   GG (a, b, c, d, x[ 0], S21); /* 17 */
212   GG (d, a, b, c, x[ 4], S22); /* 18 */
213   GG (c, d, a, b, x[ 8], S23); /* 19 */
214   GG (b, c, d, a, x[12], S24); /* 20 */
215   GG (a, b, c, d, x[ 1], S21); /* 21 */
216   GG (d, a, b, c, x[ 5], S22); /* 22 */
217   GG (c, d, a, b, x[ 9], S23); /* 23 */
218   GG (b, c, d, a, x[13], S24); /* 24 */
219   GG (a, b, c, d, x[ 2], S21); /* 25 */
220   GG (d, a, b, c, x[ 6], S22); /* 26 */
221   GG (c, d, a, b, x[10], S23); /* 27 */
222   GG (b, c, d, a, x[14], S24); /* 28 */
223   GG (a, b, c, d, x[ 3], S21); /* 29 */
224   GG (d, a, b, c, x[ 7], S22); /* 30 */
225   GG (c, d, a, b, x[11], S23); /* 31 */
226   GG (b, c, d, a, x[15], S24); /* 32 */
227 
228   /* Round 3 */
229   HH (a, b, c, d, x[ 0], S31); /* 33 */
230   HH (d, a, b, c, x[ 8], S32); /* 34 */
231   HH (c, d, a, b, x[ 4], S33); /* 35 */
232   HH (b, c, d, a, x[12], S34); /* 36 */
233   HH (a, b, c, d, x[ 2], S31); /* 37 */
234   HH (d, a, b, c, x[10], S32); /* 38 */
235   HH (c, d, a, b, x[ 6], S33); /* 39 */
236   HH (b, c, d, a, x[14], S34); /* 40 */
237   HH (a, b, c, d, x[ 1], S31); /* 41 */
238   HH (d, a, b, c, x[ 9], S32); /* 42 */
239   HH (c, d, a, b, x[ 5], S33); /* 43 */
240   HH (b, c, d, a, x[13], S34); /* 44 */
241   HH (a, b, c, d, x[ 3], S31); /* 45 */
242   HH (d, a, b, c, x[11], S32); /* 46 */
243   HH (c, d, a, b, x[ 7], S33); /* 47 */
244   HH (b, c, d, a, x[15], S34); /* 48 */
245 
246   state[0] += a;
247   state[1] += b;
248   state[2] += c;
249   state[3] += d;
250 
251   /* Zeroize sensitive information.
252    */
253   bzero((POINTER)x, sizeof (x));
254 }
255 
256 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
257      a multiple of 4.
258  */
259 static void
260 Encode(unsigned char *output, UINT4 *input, unsigned int len)
261 {
262   unsigned int i, j;
263 
264   for (i = 0, j = 0; j < len; i++, j += 4) {
265     output[j] = (unsigned char)(input[i] & 0xff);
266     output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
267     output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
268     output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
269   }
270 }
271 
272 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
273      a multiple of 4.
274  */
275 static void
276 Decode(UINT4 *output, const unsigned char *input, unsigned int len)
277 {
278   unsigned int i, j;
279 
280   for (i = 0, j = 0; j < len; i++, j += 4)
281     output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
282       (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
283 }
284 
285 #ifdef WEAK_REFS
286 /* When building libmd, provide weak references. Note: this is not
287    activated in the context of compiling these sources for internal
288    use in libcrypt.
289  */
290 #undef MD4Init
291 __weak_reference(_libmd_MD4Init, MD4Init);
292 #undef MD4Update
293 __weak_reference(_libmd_MD4Update, MD4Update);
294 #undef MD4Pad
295 __weak_reference(_libmd_MD4Pad, MD4Pad);
296 #undef MD4Final
297 __weak_reference(_libmd_MD4Final, MD4Final);
298 #endif
299