xref: /freebsd/sys/kern/md4c.c (revision 6ae1554a5d9b318f8ad53ccc39fa5a961403da73)
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 MD4Init (context)
94 MD4_CTX *context;                                        /* 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 MD4Update (context, input, inputLen)
111 MD4_CTX *context;                                        /* context */
112 const unsigned char *input;                                /* input block */
113 unsigned int inputLen;                     /* length of input block */
114 {
115   unsigned int i, index, partLen;
116 
117   /* Compute number of bytes mod 64 */
118   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
119   /* Update number of bits */
120   if ((context->count[0] += ((UINT4)inputLen << 3))
121       < ((UINT4)inputLen << 3))
122     context->count[1]++;
123   context->count[1] += ((UINT4)inputLen >> 29);
124 
125   partLen = 64 - index;
126   /* Transform as many times as possible.
127    */
128   if (inputLen >= partLen) {
129     bcopy(input, &context->buffer[index], partLen);
130     MD4Transform (context->state, context->buffer);
131 
132     for (i = partLen; i + 63 < inputLen; i += 64)
133       MD4Transform (context->state, &input[i]);
134 
135     index = 0;
136   }
137   else
138     i = 0;
139 
140   /* Buffer remaining input */
141   bcopy(&input[i], &context->buffer[index], inputLen-i);
142 }
143 
144 /* MD4 padding. */
145 void MD4Pad (context)
146 MD4_CTX *context;                                        /* context */
147 {
148   unsigned char bits[8];
149   unsigned int index, padLen;
150 
151   /* Save number of bits */
152   Encode (bits, context->count, 8);
153 
154   /* Pad out to 56 mod 64.
155    */
156   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
157   padLen = (index < 56) ? (56 - index) : (120 - index);
158   MD4Update (context, PADDING, padLen);
159 
160   /* Append length (before padding) */
161   MD4Update (context, bits, 8);
162 }
163 
164 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
165      the message digest and zeroizing the context.
166  */
167 void MD4Final (digest, context)
168 unsigned char digest[16];                         /* message digest */
169 MD4_CTX *context;                                        /* context */
170 {
171   /* Do padding */
172   MD4Pad (context);
173 
174   /* Store state in digest */
175   Encode (digest, context->state, 16);
176 
177   /* Zeroize sensitive information.
178    */
179   bzero((POINTER)context, sizeof (*context));
180 }
181 
182 /* MD4 basic transformation. Transforms state based on block.
183  */
184 static void MD4Transform (state, block)
185 UINT4 state[4];
186 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 Encode (output, input, len)
260 unsigned char *output;
261 UINT4 *input;
262 unsigned int len;
263 {
264   unsigned int i, j;
265 
266   for (i = 0, j = 0; j < len; i++, j += 4) {
267     output[j] = (unsigned char)(input[i] & 0xff);
268     output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
269     output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
270     output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
271   }
272 }
273 
274 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
275      a multiple of 4.
276  */
277 static void Decode (output, input, len)
278 
279 UINT4 *output;
280 const unsigned char *input;
281 unsigned int len;
282 {
283   unsigned int i, j;
284 
285   for (i = 0, j = 0; j < len; i++, j += 4)
286     output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
287       (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
288 }
289