md5.c - sbase - suckless unix tools
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md5.c (3857B)
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1 /* public domain md5 implementation based on rfc1321 and libtomcrypt */
2 #include <stdint.h>
3 #include <string.h>
4
5 #include "../md5.h"
6
7 static uint32_t rol(uint32_t n, int k) { return (n << k) | (n >> (32-k)); }
8 #define F(x,y,z) (z ^ (x & (y ^ z)))
9 #define G(x,y,z) (y ^ (z & (y ^ x)))
10 #define H(x,y,z) (x ^ y ^ z)
11 #define I(x,y,z) (y ^ (x | ~z))
12 #define FF(a,b,c,d,w,s,t) a += F(b,c,d) + w + t; a = rol(a,s) + b
13 #define GG(a,b,c,d,w,s,t) a += G(b,c,d) + w + t; a = rol(a,s) + b
14 #define HH(a,b,c,d,w,s,t) a += H(b,c,d) + w + t; a = rol(a,s) + b
15 #define II(a,b,c,d,w,s,t) a += I(b,c,d) + w + t; a = rol(a,s) + b
16
17 static const uint32_t tab[64] = {
18 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
19 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
20 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
21 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
22 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
23 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
24 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
25 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
26 };
27
28 static void
29 processblock(struct md5 *s, const uint8_t *buf)
30 {
31 uint32_t i, W[16], a, b, c, d;
32
33 for (i = 0; i < 16; i++) {
34 W[i] = buf[4*i];
35 W[i] |= (uint32_t)buf[4*i+1]<<8;
36 W[i] |= (uint32_t)buf[4*i+2]<<16;
37 W[i] |= (uint32_t)buf[4*i+3]<<24;
38 }
39
40 a = s->h[0];
41 b = s->h[1];
42 c = s->h[2];
43 d = s->h[3];
44
45 i = 0;
46 while (i < 16) {
47 FF(a,b,c,d, W[i], 7, tab[i]); i++;
48 FF(d,a,b,c, W[i], 12, tab[i]); i++;
49 FF(c,d,a,b, W[i], 17, tab[i]); i++;
50 FF(b,c,d,a, W[i], 22, tab[i]); i++;
51 }
52 while (i < 32) {
53 GG(a,b,c,d, W[(5*i+1)%16], 5, tab[i]); i++;
54 GG(d,a,b,c, W[(5*i+1)%16], 9, tab[i]); i++;
55 GG(c,d,a,b, W[(5*i+1)%16], 14, tab[i]); i++;
56 GG(b,c,d,a, W[(5*i+1)%16], 20, tab[i]); i++;
57 }
58 while (i < 48) {
59 HH(a,b,c,d, W[(3*i+5)%16], 4, tab[i]); i++;
60 HH(d,a,b,c, W[(3*i+5)%16], 11, tab[i]); i++;
61 HH(c,d,a,b, W[(3*i+5)%16], 16, tab[i]); i++;
62 HH(b,c,d,a, W[(3*i+5)%16], 23, tab[i]); i++;
63 }
64 while (i < 64) {
65 II(a,b,c,d, W[7*i%16], 6, tab[i]); i++;
66 II(d,a,b,c, W[7*i%16], 10, tab[i]); i++;
67 II(c,d,a,b, W[7*i%16], 15, tab[i]); i++;
68 II(b,c,d,a, W[7*i%16], 21, tab[i]); i++;
69 }
70
71 s->h[0] += a;
72 s->h[1] += b;
73 s->h[2] += c;
74 s->h[3] += d;
75 }
76
77 static void
78 pad(struct md5 *s)
79 {
80 unsigned r = s->len % 64;
81
82 s->buf[r++] = 0x80;
83 if (r > 56) {
84 memset(s->buf + r, 0, 64 - r);
85 r = 0;
86 processblock(s, s->buf);
87 }
88 memset(s->buf + r, 0, 56 - r);
89 s->len *= 8;
90 s->buf[56] = s->len;
91 s->buf[57] = s->len >> 8;
92 s->buf[58] = s->len >> 16;
93 s->buf[59] = s->len >> 24;
94 s->buf[60] = s->len >> 32;
95 s->buf[61] = s->len >> 40;
96 s->buf[62] = s->len >> 48;
97 s->buf[63] = s->len >> 56;
98 processblock(s, s->buf);
99 }
100
101 void
102 md5_init(void *ctx)
103 {
104 struct md5 *s = ctx;
105 s->len = 0;
106 s->h[0] = 0x67452301;
107 s->h[1] = 0xefcdab89;
108 s->h[2] = 0x98badcfe;
109 s->h[3] = 0x10325476;
110 }
111
112 void
113 md5_sum(void *ctx, uint8_t md[MD5_DIGEST_LENGTH])
114 {
115 struct md5 *s = ctx;
116 int i;
117
118 pad(s);
119 for (i = 0; i < 4; i++) {
120 md[4*i] = s->h[i];
121 md[4*i+1] = s->h[i] >> 8;
122 md[4*i+2] = s->h[i] >> 16;
123 md[4*i+3] = s->h[i] >> 24;
124 }
125 }
126
127 void
128 md5_update(void *ctx, const void *m, unsigned long len)
129 {
130 struct md5 *s = ctx;
131 const uint8_t *p = m;
132 unsigned r = s->len % 64;
133
134 s->len += len;
135 if (r) {
136 if (len < 64 - r) {
137 memcpy(s->buf + r, p, len);
138 return;
139 }
140 memcpy(s->buf + r, p, 64 - r);
141 len -= 64 - r;
142 p += 64 - r;
143 processblock(s, s->buf);
144 }
145 for (; len >= 64; len -= 64, p += 64)
146 processblock(s, p);
147 memcpy(s->buf, p, len);
148 }