1 /*
2  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 
7 /*
8  *	lib/crypto/md4/md4.c
9  */
10 
11 /*
12  **********************************************************************
13  ** md4.c                                                            **
14  ** RSA Data Security, Inc. MD4 Message Digest Algorithm             **
15  ** Created: 2/17/90 RLR                                             **
16  ** Revised: 1/91 SRD,AJ,BSK,JT Reference C Version                  **
17  **********************************************************************
18  */
19 
20 /*
21  **********************************************************************
22  ** Copyright (C) 1990, RSA Data Security, Inc. All rights reserved. **
23  **                                                                  **
24  ** License to copy and use this software is granted provided that   **
25  ** it is identified as the "RSA Data Security, Inc. MD4 Message     **
26  ** Digest Algorithm" in all material mentioning or referencing this **
27  ** software or this function.                                       **
28  **                                                                  **
29  ** License is also granted to make and use derivative works         **
30  ** provided that such works are identified as "derived from the RSA **
31  ** Data Security, Inc. MD4 Message Digest Algorithm" in all         **
32  ** material mentioning or referencing the derived work.             **
33  **                                                                  **
34  ** RSA Data Security, Inc. makes no representations concerning      **
35  ** either the merchantability of this software or the suitability   **
36  ** of this software for any particular purpose.  It is provided "as **
37  ** is" without express or implied warranty of any kind.             **
38  **                                                                  **
39  ** These notices must be retained in any copies of any part of this **
40  ** documentation and/or software.                                   **
41  **********************************************************************
42  */
43 
44 #include "k5-int.h"
45 #include "rsa-md4.h"
46 
47 /* forward declaration */
48 static void Transform (krb5_ui_4 *, krb5_ui_4 *);
49 
50 static const unsigned char PADDING[64] = {
51   0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
52   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
53   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
54   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
55   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
56   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
57   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
58   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
59 };
60 
61 /* F, G and H are basic MD4 functions: selection, majority, parity */
62 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
63 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
64 #define H(x, y, z) ((x) ^ (y) ^ (z))
65 
66 /* ROTATE_LEFT rotates x left n bits */
67 #define ROTATE_LEFT(x, n) ((((x) << (n)) & 0xffffffff) | ((x) >> (32-(n))))
68 
69 /* FF, GG and HH are MD4 transformations for rounds 1, 2 and 3 */
70 /* Rotation is separate from addition to prevent recomputation */
71 #define FF(a, b, c, d, x, s) \
72   {(a) += F ((b), (c), (d)) + (x); \
73    (a) &= 0xffffffff; \
74    (a) = ROTATE_LEFT ((a), (s));}
75 #define GG(a, b, c, d, x, s) \
76   {(a) += G ((b), (c), (d)) + (x) + 013240474631UL; \
77    (a) &= 0xffffffff; \
78    (a) = ROTATE_LEFT ((a), (s));}
79 #define HH(a, b, c, d, x, s) \
80   {(a) += H ((b), (c), (d)) + (x) + 015666365641UL; \
81    (a) &= 0xffffffff; \
82    (a) = ROTATE_LEFT ((a), (s));}
83 
84 void
krb5_MD4Init(krb5_MD4_CTX * mdContext)85 krb5_MD4Init (krb5_MD4_CTX *mdContext)
86 {
87   mdContext->i[0] = mdContext->i[1] = (krb5_ui_4)0;
88 
89   /* Load magic initialization constants.
90    */
91   mdContext->buf[0] = 0x67452301UL;
92   mdContext->buf[1] = 0xefcdab89UL;
93   mdContext->buf[2] = 0x98badcfeUL;
94   mdContext->buf[3] = 0x10325476UL;
95 }
96 
97 void
krb5_MD4Update(krb5_MD4_CTX * mdContext,const unsigned char * inBuf,unsigned int inLen)98 krb5_MD4Update (krb5_MD4_CTX *mdContext, const unsigned char *inBuf, unsigned int inLen)
99 {
100   krb5_ui_4 in[16];
101   int mdi;
102   unsigned int i, ii;
103 
104   /* compute number of bytes mod 64 */
105   mdi = (int)((mdContext->i[0] >> 3) & 0x3F);
106 
107   /* update number of bits */
108   if ((mdContext->i[0] + ((krb5_ui_4)inLen << 3)) < mdContext->i[0])
109     mdContext->i[1]++;
110   mdContext->i[0] += ((krb5_ui_4)inLen << 3);
111   mdContext->i[1] += ((krb5_ui_4)inLen >> 29);
112 
113   while (inLen--) {
114     /* add new character to buffer, increment mdi */
115     mdContext->in[mdi++] = *inBuf++;
116 
117     /* transform if necessary */
118     if (mdi == 0x40) {
119       for (i = 0, ii = 0; i < 16; i++, ii += 4)
120         in[i] = (((krb5_ui_4)mdContext->in[ii+3]) << 24) |
121                 (((krb5_ui_4)mdContext->in[ii+2]) << 16) |
122                 (((krb5_ui_4)mdContext->in[ii+1]) << 8) |
123                 ((krb5_ui_4)mdContext->in[ii]);
124       Transform (mdContext->buf, in);
125       mdi = 0;
126     }
127   }
128 }
129 
130 void
krb5_MD4Final(krb5_MD4_CTX * mdContext)131 krb5_MD4Final (krb5_MD4_CTX *mdContext)
132 {
133   krb5_ui_4 in[16];
134   int mdi;
135   unsigned int i, ii;
136   unsigned int padLen;
137 
138   /* save number of bits */
139   in[14] = mdContext->i[0];
140   in[15] = mdContext->i[1];
141 
142   /* compute number of bytes mod 64 */
143   mdi = (int)((mdContext->i[0] >> 3) & 0x3F);
144 
145   /* pad out to 56 mod 64 */
146   padLen = (mdi < 56) ? (56 - mdi) : (120 - mdi);
147   krb5_MD4Update (mdContext, PADDING, padLen);
148 
149   /* append length in bits and transform */
150   for (i = 0, ii = 0; i < 14; i++, ii += 4)
151     in[i] = (((krb5_ui_4)mdContext->in[ii+3]) << 24) |
152             (((krb5_ui_4)mdContext->in[ii+2]) << 16) |
153             (((krb5_ui_4)mdContext->in[ii+1]) << 8) |
154             ((krb5_ui_4)mdContext->in[ii]);
155   Transform (mdContext->buf, in);
156 
157 
158   /* store buffer in digest */
159   for (i = 0, ii = 0; i < 4; i++, ii += 4) {
160     mdContext->digest[ii] = (unsigned char)(mdContext->buf[i] & 0xFF);
161     mdContext->digest[ii+1] =
162       (unsigned char)((mdContext->buf[i] >> 8) & 0xFF);
163     mdContext->digest[ii+2] =
164       (unsigned char)((mdContext->buf[i] >> 16) & 0xFF);
165     mdContext->digest[ii+3] =
166       (unsigned char)((mdContext->buf[i] >> 24) & 0xFF);
167   }
168 }
169 
170 /* Basic MD4 step. Transform buf based on in.
171  */
Transform(krb5_ui_4 * buf,krb5_ui_4 * in)172 static void Transform (krb5_ui_4 *buf, krb5_ui_4 *in)
173 {
174   register krb5_ui_4 a = buf[0], b = buf[1], c = buf[2], d = buf[3];
175 
176 #ifdef CONFIG_SMALL
177   int i;
178 #define ROTATE { krb5_ui_4 temp; temp = d, d = c, c = b, b = a, a = temp; }
179   for (i = 0; i < 16; i++) {
180       static const unsigned char round1consts[] = { 3, 7, 11, 19, };
181       FF (a, b, c, d, in[i], round1consts[i%4]); ROTATE;
182   }
183   for (i = 0; i < 16; i++) {
184       static const unsigned char round2indices[] = {
185 	  0,4,8,12,1,5,9,13,2,6,10,14,3,7,11,15
186       };
187       static const unsigned char round2consts[] = { 3, 5, 9, 13 };
188       GG (a, b, c, d, in[round2indices[i]], round2consts[i%4]); ROTATE;
189   }
190   for (i = 0; i < 16; i++) {
191       static const unsigned char round3indices[] = {
192 	  0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15
193       };
194       static const unsigned char round3consts[] = { 3, 9, 11, 15 };
195       HH (a, b, c, d, in[round3indices[i]], round3consts[i%4]); ROTATE;
196   }
197 #else
198   /* Round 1 */
199   FF (a, b, c, d, in[ 0],  3);
200   FF (d, a, b, c, in[ 1],  7);
201   FF (c, d, a, b, in[ 2], 11);
202   FF (b, c, d, a, in[ 3], 19);
203   FF (a, b, c, d, in[ 4],  3);
204   FF (d, a, b, c, in[ 5],  7);
205   FF (c, d, a, b, in[ 6], 11);
206   FF (b, c, d, a, in[ 7], 19);
207   FF (a, b, c, d, in[ 8],  3);
208   FF (d, a, b, c, in[ 9],  7);
209   FF (c, d, a, b, in[10], 11);
210   FF (b, c, d, a, in[11], 19);
211   FF (a, b, c, d, in[12],  3);
212   FF (d, a, b, c, in[13],  7);
213   FF (c, d, a, b, in[14], 11);
214   FF (b, c, d, a, in[15], 19);
215 
216   /* Round 2 */
217   GG (a, b, c, d, in[ 0],  3);
218   GG (d, a, b, c, in[ 4],  5);
219   GG (c, d, a, b, in[ 8],  9);
220   GG (b, c, d, a, in[12], 13);
221   GG (a, b, c, d, in[ 1],  3);
222   GG (d, a, b, c, in[ 5],  5);
223   GG (c, d, a, b, in[ 9],  9);
224   GG (b, c, d, a, in[13], 13);
225   GG (a, b, c, d, in[ 2],  3);
226   GG (d, a, b, c, in[ 6],  5);
227   GG (c, d, a, b, in[10],  9);
228   GG (b, c, d, a, in[14], 13);
229   GG (a, b, c, d, in[ 3],  3);
230   GG (d, a, b, c, in[ 7],  5);
231   GG (c, d, a, b, in[11],  9);
232   GG (b, c, d, a, in[15], 13);
233 
234   /* Round 3 */
235   HH (a, b, c, d, in[ 0],  3);
236   HH (d, a, b, c, in[ 8],  9);
237   HH (c, d, a, b, in[ 4], 11);
238   HH (b, c, d, a, in[12], 15);
239   HH (a, b, c, d, in[ 2],  3);
240   HH (d, a, b, c, in[10],  9);
241   HH (c, d, a, b, in[ 6], 11);
242   HH (b, c, d, a, in[14], 15);
243   HH (a, b, c, d, in[ 1],  3);
244   HH (d, a, b, c, in[ 9],  9);
245   HH (c, d, a, b, in[ 5], 11);
246   HH (b, c, d, a, in[13], 15);
247   HH (a, b, c, d, in[ 3],  3);
248   HH (d, a, b, c, in[11],  9);
249   HH (c, d, a, b, in[ 7], 11);
250   HH (b, c, d, a, in[15], 15);
251 #endif
252 
253   buf[0] += a;
254   buf[1] += b;
255   buf[2] += c;
256   buf[3] += d;
257 }
258 
259 /*
260  **********************************************************************
261  ** End of md4.c                                                     **
262  ******************************* (cut) ********************************
263  */
264