1 /*
2 * Copyright (c) 2003, 2007-14 Matteo Frigo
3 * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 */
20
21 /*
22 independent implementation of Ron Rivest's MD5 message-digest
23 algorithm, based on rfc 1321.
24
25 Optimized for small code size, not speed. Works as long as
26 sizeof(md5uint) >= 4.
27 */
28
29 #include "kernel/ifftw.h"
30
31 /* sintab[i] = 4294967296.0 * abs(sin((double)(i + 1))) */
32 static const md5uint sintab[64] = {
33 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
34 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
35 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
36 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
37 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
38 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
39 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
40 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
41 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
42 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
43 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
44 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
45 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
46 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
47 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
48 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
49 };
50
51 /* see rfc 1321 section 3.4 */
52 static const struct roundtab {
53 char k;
54 char s;
55 } roundtab[64] = {
56 { 0, 7}, { 1, 12}, { 2, 17}, { 3, 22},
57 { 4, 7}, { 5, 12}, { 6, 17}, { 7, 22},
58 { 8, 7}, { 9, 12}, { 10, 17}, { 11, 22},
59 { 12, 7}, { 13, 12}, { 14, 17}, { 15, 22},
60 { 1, 5}, { 6, 9}, { 11, 14}, { 0, 20},
61 { 5, 5}, { 10, 9}, { 15, 14}, { 4, 20},
62 { 9, 5}, { 14, 9}, { 3, 14}, { 8, 20},
63 { 13, 5}, { 2, 9}, { 7, 14}, { 12, 20},
64 { 5, 4}, { 8, 11}, { 11, 16}, { 14, 23},
65 { 1, 4}, { 4, 11}, { 7, 16}, { 10, 23},
66 { 13, 4}, { 0, 11}, { 3, 16}, { 6, 23},
67 { 9, 4}, { 12, 11}, { 15, 16}, { 2, 23},
68 { 0, 6}, { 7, 10}, { 14, 15}, { 5, 21},
69 { 12, 6}, { 3, 10}, { 10, 15}, { 1, 21},
70 { 8, 6}, { 15, 10}, { 6, 15}, { 13, 21},
71 { 4, 6}, { 11, 10}, { 2, 15}, { 9, 21}
72 };
73
74 #define rol(a, s) ((a << (int)(s)) | (a >> (32 - (int)(s))))
75
doblock(md5sig state,const unsigned char * data)76 static void doblock(md5sig state, const unsigned char *data)
77 {
78 md5uint a, b, c, d, t, x[16];
79 const md5uint msk = (md5uint)0xffffffffUL;
80 int i;
81
82 /* encode input bytes into md5uint */
83 for (i = 0; i < 16; ++i) {
84 const unsigned char *p = data + 4 * i;
85 x[i] = (unsigned)p[0] | ((unsigned)p[1] << 8) | ((unsigned)p[2] << 16) | ((unsigned)p[3] << 24);
86 }
87
88 a = state[0]; b = state[1]; c = state[2]; d = state[3];
89 for (i = 0; i < 64; ++i) {
90 const struct roundtab *p = roundtab + i;
91 switch (i >> 4) {
92 case 0: a += (b & c) | (~b & d); break;
93 case 1: a += (b & d) | (c & ~d); break;
94 case 2: a += b ^ c ^ d; break;
95 case 3: a += c ^ (b | ~d); break;
96 }
97 a += sintab[i];
98 a += x[(int)(p->k)];
99 a &= msk;
100 t = b + rol(a, p->s);
101 a = d; d = c; c = b; b = t;
102 }
103 state[0] = (state[0] + a) & msk;
104 state[1] = (state[1] + b) & msk;
105 state[2] = (state[2] + c) & msk;
106 state[3] = (state[3] + d) & msk;
107 }
108
109
X(md5begin)110 void X(md5begin)(md5 *p)
111 {
112 p->s[0] = 0x67452301;
113 p->s[1] = 0xefcdab89;
114 p->s[2] = 0x98badcfe;
115 p->s[3] = 0x10325476;
116 p->l = 0;
117 }
118
X(md5putc)119 void X(md5putc)(md5 *p, unsigned char c)
120 {
121 p->c[p->l % 64] = c;
122 if (((++p->l) % 64) == 0) doblock(p->s, p->c);
123 }
124
X(md5end)125 void X(md5end)(md5 *p)
126 {
127 unsigned l, i;
128
129 l = 8 * p->l; /* length before padding, in bits */
130
131 /* rfc 1321 section 3.1: padding */
132 X(md5putc)(p, 0x80);
133 while ((p->l % 64) != 56) X(md5putc)(p, 0x00);
134
135 /* rfc 1321 section 3.2: length (little endian) */
136 for (i = 0; i < 8; ++i) {
137 X(md5putc)(p, (unsigned char)(l & 0xFF));
138 l = l >> 8;
139 }
140
141 /* Now p->l % 64 == 0 and signature is in p->s */
142 }
143