1 /* sha.c
2 **
3 ** Copyright 2013, The Android Open Source Project
4 **
5 ** Redistribution and use in source and binary forms, with or without
6 ** modification, are permitted provided that the following conditions are met:
7 ** * Redistributions of source code must retain the above copyright
8 ** notice, this list of conditions and the following disclaimer.
9 ** * Redistributions in binary form must reproduce the above copyright
10 ** notice, this list of conditions and the following disclaimer in the
11 ** documentation and/or other materials provided with the distribution.
12 ** * Neither the name of Google Inc. nor the names of its contributors may
13 ** be used to endorse or promote products derived from this software
14 ** without specific prior written permission.
15 **
16 ** THIS SOFTWARE IS PROVIDED BY Google Inc. ``AS IS'' AND ANY EXPRESS OR
17 ** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 ** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
19 ** EVENT SHALL Google Inc. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 ** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 ** OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 ** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 ** OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 ** ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 // Optimized for minimal code size.
29
30 #include "mincrypt/sha.h"
31
32 #include <stdio.h>
33 #include <string.h>
34 #include <stdint.h>
35
36 #define rol(bits, value) (((value) << (bits)) | ((value) >> (32 - (bits))))
37
SHA1_Transform(SHA_CTX * ctx)38 static void SHA1_Transform(SHA_CTX* ctx) {
39 uint32_t W[80];
40 uint32_t A, B, C, D, E;
41 uint8_t* p = ctx->buf;
42 int t;
43
44 for(t = 0; t < 16; ++t) {
45 uint32_t tmp = *p++ << 24;
46 tmp |= *p++ << 16;
47 tmp |= *p++ << 8;
48 tmp |= *p++;
49 W[t] = tmp;
50 }
51
52 for(; t < 80; t++) {
53 W[t] = rol(1,W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16]);
54 }
55
56 A = ctx->state[0];
57 B = ctx->state[1];
58 C = ctx->state[2];
59 D = ctx->state[3];
60 E = ctx->state[4];
61
62 for(t = 0; t < 80; t++) {
63 uint32_t tmp = rol(5,A) + E + W[t];
64
65 if (t < 20)
66 tmp += (D^(B&(C^D))) + 0x5A827999;
67 else if ( t < 40)
68 tmp += (B^C^D) + 0x6ED9EBA1;
69 else if ( t < 60)
70 tmp += ((B&C)|(D&(B|C))) + 0x8F1BBCDC;
71 else
72 tmp += (B^C^D) + 0xCA62C1D6;
73
74 E = D;
75 D = C;
76 C = rol(30,B);
77 B = A;
78 A = tmp;
79 }
80
81 ctx->state[0] += A;
82 ctx->state[1] += B;
83 ctx->state[2] += C;
84 ctx->state[3] += D;
85 ctx->state[4] += E;
86 }
87
88 static const HASH_VTAB SHA_VTAB = {
89 SHA_init,
90 SHA_update,
91 SHA_final,
92 SHA_hash,
93 SHA_DIGEST_SIZE
94 };
95
SHA_init(SHA_CTX * ctx)96 void SHA_init(SHA_CTX* ctx) {
97 ctx->f = &SHA_VTAB;
98 ctx->state[0] = 0x67452301;
99 ctx->state[1] = 0xEFCDAB89;
100 ctx->state[2] = 0x98BADCFE;
101 ctx->state[3] = 0x10325476;
102 ctx->state[4] = 0xC3D2E1F0;
103 ctx->count = 0;
104 }
105
106
SHA_update(SHA_CTX * ctx,const void * data,int len)107 void SHA_update(SHA_CTX* ctx, const void* data, int len) {
108 int i = (int) (ctx->count & 63);
109 const uint8_t* p = (const uint8_t*)data;
110
111 ctx->count += len;
112
113 while (len--) {
114 ctx->buf[i++] = *p++;
115 if (i == 64) {
116 SHA1_Transform(ctx);
117 i = 0;
118 }
119 }
120 }
121
122
SHA_final(SHA_CTX * ctx)123 const uint8_t* SHA_final(SHA_CTX* ctx) {
124 uint8_t *p = ctx->buf;
125 uint64_t cnt = ctx->count * 8;
126 int i;
127
128 SHA_update(ctx, (uint8_t*)"\x80", 1);
129 while ((ctx->count & 63) != 56) {
130 SHA_update(ctx, (uint8_t*)"\0", 1);
131 }
132 for (i = 0; i < 8; ++i) {
133 uint8_t tmp = (uint8_t) (cnt >> ((7 - i) * 8));
134 SHA_update(ctx, &tmp, 1);
135 }
136
137 for (i = 0; i < 5; i++) {
138 uint32_t tmp = ctx->state[i];
139 *p++ = tmp >> 24;
140 *p++ = tmp >> 16;
141 *p++ = tmp >> 8;
142 *p++ = tmp >> 0;
143 }
144
145 return ctx->buf;
146 }
147
148 /* Convenience function */
SHA_hash(const void * data,int len,uint8_t * digest)149 const uint8_t* SHA_hash(const void* data, int len, uint8_t* digest) {
150 SHA_CTX ctx;
151 SHA_init(&ctx);
152 SHA_update(&ctx, data, len);
153 memcpy(digest, SHA_final(&ctx), SHA_DIGEST_SIZE);
154 return digest;
155 }
156