1/*
2SHA-1 in C
3By Steve Reid <steve@edmweb.com>
4100% Public Domain
5
6Test Vectors (from FIPS PUB 180-1)
7"abc"
8 A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
9"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
10 84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
11A million repetitions of "a"
12 34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
13*/
14
15/* #define LITTLE_ENDIAN * This should be #define'd already, if true. */
16/* #define SHA1HANDSOFF * Copies data before messing with it. */
17
18#define SHA1HANDSOFF
19
20#include <stdio.h>
21#include <string.h>
22
23/* for uint32_t */
24#include <stdint.h>
25
26#include "sha1.h"
27
28
29#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
30
31/* blk0() and blk() perform the initial expand. */
32/* I got the idea of expanding during the round function from SSLeay */
33#if BYTE_ORDER == LITTLE_ENDIAN
34#define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
35 |(rol(block->l[i],8)&0x00FF00FF))
36#elif BYTE_ORDER == BIG_ENDIAN
37#define blk0(i) block->l[i]
38#else
39#error "Endianness not defined!"
40#endif
41#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
42 ^block->l[(i+2)&15]^block->l[i&15],1))
43
44/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
45#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
46#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
47#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
48#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
49#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
50
51
52/* Hash a single 512-bit block. This is the core of the algorithm. */
53
54void SHA1Transform(
55 uint32_t state[5],
56 const unsigned char buffer[64]
57)
58{
59 uint32_t a, b, c, d, e;
60
61 typedef union
62 {
63 unsigned char c[64];
64 uint32_t l[16];
65 } CHAR64LONG16;
66
67#ifdef SHA1HANDSOFF
68 CHAR64LONG16 block[1]; /* use array to appear as a pointer */
69
70 memcpy(block, buffer, 64);
71#else
72 /* The following had better never be used because it causes the
73 * pointer-to-const buffer to be cast into a pointer to non-const.
74 * And the result is written through. I threw a "const" in, hoping
75 * this will cause a diagnostic.
76 */
77 CHAR64LONG16 *block = (const CHAR64LONG16 *) buffer;
78#endif
79 /* Copy context->state[] to working vars */
80 a = state[0];
81 b = state[1];
82 c = state[2];
83 d = state[3];
84 e = state[4];
85 /* 4 rounds of 20 operations each. Loop unrolled. */
86 R0(a, b, c, d, e, 0);
87 R0(e, a, b, c, d, 1);
88 R0(d, e, a, b, c, 2);
89 R0(c, d, e, a, b, 3);
90 R0(b, c, d, e, a, 4);
91 R0(a, b, c, d, e, 5);
92 R0(e, a, b, c, d, 6);
93 R0(d, e, a, b, c, 7);
94 R0(c, d, e, a, b, 8);
95 R0(b, c, d, e, a, 9);
96 R0(a, b, c, d, e, 10);
97 R0(e, a, b, c, d, 11);
98 R0(d, e, a, b, c, 12);
99 R0(c, d, e, a, b, 13);
100 R0(b, c, d, e, a, 14);
101 R0(a, b, c, d, e, 15);
102 R1(e, a, b, c, d, 16);
103 R1(d, e, a, b, c, 17);
104 R1(c, d, e, a, b, 18);
105 R1(b, c, d, e, a, 19);
106 R2(a, b, c, d, e, 20);
107 R2(e, a, b, c, d, 21);
108 R2(d, e, a, b, c, 22);
109 R2(c, d, e, a, b, 23);
110 R2(b, c, d, e, a, 24);
111 R2(a, b, c, d, e, 25);
112 R2(e, a, b, c, d, 26);
113 R2(d, e, a, b, c, 27);
114 R2(c, d, e, a, b, 28);
115 R2(b, c, d, e, a, 29);
116 R2(a, b, c, d, e, 30);
117 R2(e, a, b, c, d, 31);
118 R2(d, e, a, b, c, 32);
119 R2(c, d, e, a, b, 33);
120 R2(b, c, d, e, a, 34);
121 R2(a, b, c, d, e, 35);
122 R2(e, a, b, c, d, 36);
123 R2(d, e, a, b, c, 37);
124 R2(c, d, e, a, b, 38);
125 R2(b, c, d, e, a, 39);
126 R3(a, b, c, d, e, 40);
127 R3(e, a, b, c, d, 41);
128 R3(d, e, a, b, c, 42);
129 R3(c, d, e, a, b, 43);
130 R3(b, c, d, e, a, 44);
131 R3(a, b, c, d, e, 45);
132 R3(e, a, b, c, d, 46);
133 R3(d, e, a, b, c, 47);
134 R3(c, d, e, a, b, 48);
135 R3(b, c, d, e, a, 49);
136 R3(a, b, c, d, e, 50);
137 R3(e, a, b, c, d, 51);
138 R3(d, e, a, b, c, 52);
139 R3(c, d, e, a, b, 53);
140 R3(b, c, d, e, a, 54);
141 R3(a, b, c, d, e, 55);
142 R3(e, a, b, c, d, 56);
143 R3(d, e, a, b, c, 57);
144 R3(c, d, e, a, b, 58);
145 R3(b, c, d, e, a, 59);
146 R4(a, b, c, d, e, 60);
147 R4(e, a, b, c, d, 61);
148 R4(d, e, a, b, c, 62);
149 R4(c, d, e, a, b, 63);
150 R4(b, c, d, e, a, 64);
151 R4(a, b, c, d, e, 65);
152 R4(e, a, b, c, d, 66);
153 R4(d, e, a, b, c, 67);
154 R4(c, d, e, a, b, 68);
155 R4(b, c, d, e, a, 69);
156 R4(a, b, c, d, e, 70);
157 R4(e, a, b, c, d, 71);
158 R4(d, e, a, b, c, 72);
159 R4(c, d, e, a, b, 73);
160 R4(b, c, d, e, a, 74);
161 R4(a, b, c, d, e, 75);
162 R4(e, a, b, c, d, 76);
163 R4(d, e, a, b, c, 77);
164 R4(c, d, e, a, b, 78);
165 R4(b, c, d, e, a, 79);
166 /* Add the working vars back into context.state[] */
167 state[0] += a;
168 state[1] += b;
169 state[2] += c;
170 state[3] += d;
171 state[4] += e;
172 /* Wipe variables */
173 a = b = c = d = e = 0;
174#ifdef SHA1HANDSOFF
175 memset(block, '\0', sizeof(block));
176#endif
177}
178
179
180/* SHA1Init - Initialize new context */
181
182void SHA1Init(
183 SHA1_CTX * context
184)
185{
186 /* SHA1 initialization constants */
187 context->state[0] = 0x67452301;
188 context->state[1] = 0xEFCDAB89;
189 context->state[2] = 0x98BADCFE;
190 context->state[3] = 0x10325476;
191 context->state[4] = 0xC3D2E1F0;
192 context->count[0] = context->count[1] = 0;
193}
194
195
196/* Run your data through this. */
197
198void SHA1Update(
199 SHA1_CTX * context,
200 const unsigned char *data,
201 uint32_t len
202)
203{
204 uint32_t i;
205
206 uint32_t j;
207
208 j = context->count[0];
209 if ((context->count[0] += len << 3) < j)
210 context->count[1]++;
211 context->count[1] += (len >> 29);
212 j = (j >> 3) & 63;
213 if ((j + len) > 63)
214 {
215 memcpy(&context->buffer[j], data, (i = 64 - j));
216 SHA1Transform(context->state, context->buffer);
217 for (; i + 63 < len; i += 64)
218 {
219 SHA1Transform(context->state, &data[i]);
220 }
221 j = 0;
222 }
223 else
224 i = 0;
225 memcpy(&context->buffer[j], &data[i], len - i);
226}
227
228
229/* Add padding and return the message digest. */
230
231void SHA1Final(
232 unsigned char digest[20],
233 SHA1_CTX * context
234)
235{
236 unsigned i;
237
238 unsigned char finalcount[8];
239
240 unsigned char c;
241
242#if 0 /* untested "improvement" by DHR */
243 /* Convert context->count to a sequence of bytes
244 * in finalcount. Second element first, but
245 * big-endian order within element.
246 * But we do it all backwards.
247 */
248 unsigned char *fcp = &finalcount[8];
249
250 for (i = 0; i < 2; i++)
251 {
252 uint32_t t = context->count[i];
253
254 int j;
255
256 for (j = 0; j < 4; t >>= 8, j++)
257 *--fcp = (unsigned char) t}
258#else
259 for (i = 0; i < 8; i++)
260 {
261 finalcount[i] = (unsigned char) ((context->count[(i >= 4 ? 0 : 1)] >> ((3 - (i & 3)) * 8)) & 255); /* Endian independent */
262 }
263#endif
264 c = 0200;
265 SHA1Update(context, &c, 1);
266 while ((context->count[0] & 504) != 448)
267 {
268 c = 0000;
269 SHA1Update(context, &c, 1);
270 }
271 SHA1Update(context, finalcount, 8); /* Should cause a SHA1Transform() */
272 for (i = 0; i < 20; i++)
273 {
274 digest[i] = (unsigned char)
275 ((context->state[i >> 2] >> ((3 - (i & 3)) * 8)) & 255);
276 }
277 /* Wipe variables */
278 memset(context, '\0', sizeof(*context));
279 memset(&finalcount, '\0', sizeof(finalcount));
280}
281
282void SHA1(
283 char *hash_out,
284 const char *str,
285 uint32_t len)
286{
287 SHA1_CTX ctx;
288 unsigned int ii;
289
290 SHA1Init(&ctx);
291 for (ii=0; ii<len; ii+=1)
292 SHA1Update(&ctx, (const unsigned char*)str + ii, 1);
293 SHA1Final((unsigned char *)hash_out, &ctx);
294}
295