1/* public domain sha1 implementation based on rfc3174 and libtomcrypt */
2#include <stdint.h>
3#include <string.h>
4
5#include "../sha1.h"
6
7static uint32_t rol(uint32_t n, int k) { return (n << k) | (n >> (32-k)); }
8#define F0(b,c,d) (d ^ (b & (c ^ d)))
9#define F1(b,c,d) (b ^ c ^ d)
10#define F2(b,c,d) ((b & c) | (d & (b | c)))
11#define F3(b,c,d) (b ^ c ^ d)
12#define G0(a,b,c,d,e,i) e += rol(a,5)+F0(b,c,d)+W[i]+0x5A827999; b = rol(b,30)
13#define G1(a,b,c,d,e,i) e += rol(a,5)+F1(b,c,d)+W[i]+0x6ED9EBA1; b = rol(b,30)
14#define G2(a,b,c,d,e,i) e += rol(a,5)+F2(b,c,d)+W[i]+0x8F1BBCDC; b = rol(b,30)
15#define G3(a,b,c,d,e,i) e += rol(a,5)+F3(b,c,d)+W[i]+0xCA62C1D6; b = rol(b,30)
16
17static void
18processblock(struct sha1 *s, const uint8_t *buf)
19{
20 uint32_t W[80], a, b, c, d, e;
21 int i;
22
23 for (i = 0; i < 16; i++) {
24 W[i] = (uint32_t)buf[4*i]<<24;
25 W[i] |= (uint32_t)buf[4*i+1]<<16;
26 W[i] |= (uint32_t)buf[4*i+2]<<8;
27 W[i] |= buf[4*i+3];
28 }
29 for (; i < 80; i++)
30 W[i] = rol(W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16], 1);
31 a = s->h[0];
32 b = s->h[1];
33 c = s->h[2];
34 d = s->h[3];
35 e = s->h[4];
36 for (i = 0; i < 20; ) {
37 G0(a,b,c,d,e,i++);
38 G0(e,a,b,c,d,i++);
39 G0(d,e,a,b,c,i++);
40 G0(c,d,e,a,b,i++);
41 G0(b,c,d,e,a,i++);
42 }
43 while (i < 40) {
44 G1(a,b,c,d,e,i++);
45 G1(e,a,b,c,d,i++);
46 G1(d,e,a,b,c,i++);
47 G1(c,d,e,a,b,i++);
48 G1(b,c,d,e,a,i++);
49 }
50 while (i < 60) {
51 G2(a,b,c,d,e,i++);
52 G2(e,a,b,c,d,i++);
53 G2(d,e,a,b,c,i++);
54 G2(c,d,e,a,b,i++);
55 G2(b,c,d,e,a,i++);
56 }
57 while (i < 80) {
58 G3(a,b,c,d,e,i++);
59 G3(e,a,b,c,d,i++);
60 G3(d,e,a,b,c,i++);
61 G3(c,d,e,a,b,i++);
62 G3(b,c,d,e,a,i++);
63 }
64 s->h[0] += a;
65 s->h[1] += b;
66 s->h[2] += c;
67 s->h[3] += d;
68 s->h[4] += e;
69}
70
71static void
72pad(struct sha1 *s)
73{
74 unsigned r = s->len % 64;
75
76 s->buf[r++] = 0x80;
77 if (r > 56) {
78 memset(s->buf + r, 0, 64 - r);
79 r = 0;
80 processblock(s, s->buf);
81 }
82 memset(s->buf + r, 0, 56 - r);
83 s->len *= 8;
84 s->buf[56] = s->len >> 56;
85 s->buf[57] = s->len >> 48;
86 s->buf[58] = s->len >> 40;
87 s->buf[59] = s->len >> 32;
88 s->buf[60] = s->len >> 24;
89 s->buf[61] = s->len >> 16;
90 s->buf[62] = s->len >> 8;
91 s->buf[63] = s->len;
92 processblock(s, s->buf);
93}
94
95void
96sha1_init(void *ctx)
97{
98 struct sha1 *s = ctx;
99
100 s->len = 0;
101 s->h[0] = 0x67452301;
102 s->h[1] = 0xEFCDAB89;
103 s->h[2] = 0x98BADCFE;
104 s->h[3] = 0x10325476;
105 s->h[4] = 0xC3D2E1F0;
106}
107
108void
109sha1_sum(void *ctx, uint8_t md[SHA1_DIGEST_LENGTH])
110{
111 struct sha1 *s = ctx;
112 int i;
113
114 pad(s);
115 for (i = 0; i < 5; i++) {
116 md[4*i] = s->h[i] >> 24;
117 md[4*i+1] = s->h[i] >> 16;
118 md[4*i+2] = s->h[i] >> 8;
119 md[4*i+3] = s->h[i];
120 }
121}
122
123void
124sha1_update(void *ctx, const void *m, unsigned long len)
125{
126 struct sha1 *s = ctx;
127 const uint8_t *p = m;
128 unsigned r = s->len % 64;
129
130 s->len += len;
131 if (r) {
132 if (len < 64 - r) {
133 memcpy(s->buf + r, p, len);
134 return;
135 }
136 memcpy(s->buf + r, p, 64 - r);
137 len -= 64 - r;
138 p += 64 - r;
139 processblock(s, s->buf);
140 }
141 for (; len >= 64; len -= 64, p += 64)
142 processblock(s, p);
143 memcpy(s->buf, p, len);
144}
