sha256.c - sbase - suckless unix tools | |
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sha256.c (3600B) | |
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1 /* public domain sha256 implementation based on fips180-3 */ | |
2 #include <ctype.h> | |
3 #include <stdint.h> | |
4 #include <stdio.h> | |
5 #include <stdlib.h> | |
6 #include <string.h> | |
7 | |
8 #include "../sha256.h" | |
9 | |
10 static uint32_t ror(uint32_t n, int k) { return (n >> k) | (n << (32-k))… | |
11 #define Ch(x,y,z) (z ^ (x & (y ^ z))) | |
12 #define Maj(x,y,z) ((x & y) | (z & (x | y))) | |
13 #define S0(x) (ror(x,2) ^ ror(x,13) ^ ror(x,22)) | |
14 #define S1(x) (ror(x,6) ^ ror(x,11) ^ ror(x,25)) | |
15 #define R0(x) (ror(x,7) ^ ror(x,18) ^ (x>>3)) | |
16 #define R1(x) (ror(x,17) ^ ror(x,19) ^ (x>>10)) | |
17 | |
18 static const uint32_t K[64] = { | |
19 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, … | |
20 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, … | |
21 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, … | |
22 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, … | |
23 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, … | |
24 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, … | |
25 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, … | |
26 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, … | |
27 }; | |
28 | |
29 static void | |
30 processblock(struct sha256 *s, const uint8_t *buf) | |
31 { | |
32 uint32_t W[64], t1, t2, a, b, c, d, e, f, g, h; | |
33 int i; | |
34 | |
35 for (i = 0; i < 16; i++) { | |
36 W[i] = (uint32_t)buf[4*i]<<24; | |
37 W[i] |= (uint32_t)buf[4*i+1]<<16; | |
38 W[i] |= (uint32_t)buf[4*i+2]<<8; | |
39 W[i] |= buf[4*i+3]; | |
40 } | |
41 for (; i < 64; i++) | |
42 W[i] = R1(W[i-2]) + W[i-7] + R0(W[i-15]) + W[i-16]; | |
43 a = s->h[0]; | |
44 b = s->h[1]; | |
45 c = s->h[2]; | |
46 d = s->h[3]; | |
47 e = s->h[4]; | |
48 f = s->h[5]; | |
49 g = s->h[6]; | |
50 h = s->h[7]; | |
51 for (i = 0; i < 64; i++) { | |
52 t1 = h + S1(e) + Ch(e,f,g) + K[i] + W[i]; | |
53 t2 = S0(a) + Maj(a,b,c); | |
54 h = g; | |
55 g = f; | |
56 f = e; | |
57 e = d + t1; | |
58 d = c; | |
59 c = b; | |
60 b = a; | |
61 a = t1 + t2; | |
62 } | |
63 s->h[0] += a; | |
64 s->h[1] += b; | |
65 s->h[2] += c; | |
66 s->h[3] += d; | |
67 s->h[4] += e; | |
68 s->h[5] += f; | |
69 s->h[6] += g; | |
70 s->h[7] += h; | |
71 } | |
72 | |
73 static void | |
74 pad(struct sha256 *s) | |
75 { | |
76 unsigned r = s->len % 64; | |
77 | |
78 s->buf[r++] = 0x80; | |
79 if (r > 56) { | |
80 memset(s->buf + r, 0, 64 - r); | |
81 r = 0; | |
82 processblock(s, s->buf); | |
83 } | |
84 memset(s->buf + r, 0, 56 - r); | |
85 s->len *= 8; | |
86 s->buf[56] = s->len >> 56; | |
87 s->buf[57] = s->len >> 48; | |
88 s->buf[58] = s->len >> 40; | |
89 s->buf[59] = s->len >> 32; | |
90 s->buf[60] = s->len >> 24; | |
91 s->buf[61] = s->len >> 16; | |
92 s->buf[62] = s->len >> 8; | |
93 s->buf[63] = s->len; | |
94 processblock(s, s->buf); | |
95 } | |
96 | |
97 void | |
98 sha256_init(void *ctx) | |
99 { | |
100 struct sha256 *s = ctx; | |
101 s->len = 0; | |
102 s->h[0] = 0x6a09e667; | |
103 s->h[1] = 0xbb67ae85; | |
104 s->h[2] = 0x3c6ef372; | |
105 s->h[3] = 0xa54ff53a; | |
106 s->h[4] = 0x510e527f; | |
107 s->h[5] = 0x9b05688c; | |
108 s->h[6] = 0x1f83d9ab; | |
109 s->h[7] = 0x5be0cd19; | |
110 } | |
111 | |
112 void | |
113 sha256_sum_n(void *ctx, uint8_t *md, int n) | |
114 { | |
115 struct sha256 *s = ctx; | |
116 int i; | |
117 | |
118 pad(s); | |
119 for (i = 0; i < n; i++) { | |
120 md[4*i] = s->h[i] >> 24; | |
121 md[4*i+1] = s->h[i] >> 16; | |
122 md[4*i+2] = s->h[i] >> 8; | |
123 md[4*i+3] = s->h[i]; | |
124 } | |
125 } | |
126 | |
127 void | |
128 sha256_sum(void *ctx, uint8_t md[SHA256_DIGEST_LENGTH]) | |
129 { | |
130 sha256_sum_n(ctx, md, 8); | |
131 } | |
132 | |
133 void | |
134 sha256_update(void *ctx, const void *m, unsigned long len) | |
135 { | |
136 struct sha256 *s = ctx; | |
137 const uint8_t *p = m; | |
138 unsigned r = s->len % 64; | |
139 | |
140 s->len += len; | |
141 if (r) { | |
142 if (len < 64 - r) { | |
143 memcpy(s->buf + r, p, len); | |
144 return; | |
145 } | |
146 memcpy(s->buf + r, p, 64 - r); | |
147 len -= 64 - r; | |
148 p += 64 - r; | |
149 processblock(s, s->buf); | |
150 } | |
151 for (; len >= 64; len -= 64, p += 64) | |
152 processblock(s, p); | |
153 memcpy(s->buf, p, len); | |
154 } |