jcs.org
mutt stable branch with some hacks
1/*
2 SHA-1 in C
3
4 By Steve Reid <steve@edmweb.com>, with small changes to make it
5 fit into mutt by Thomas Roessler <roessler@does-not-exist.org>.
6
7 100% Public Domain.
8
9 Test Vectors (from FIPS PUB 180-1)
10 "abc"
11 A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
12 "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
13 84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
14 A million repetitions of "a"
15 34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
16*/
17
18#define SHA1HANDSOFF
19
20#if HAVE_CONFIG_H
21# include "config.h"
22#endif
23
24#include <string.h>
25
26#include "sha1.h"
27
28#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
29
30/* blk0() and blk() perform the initial expand. */
31/* I got the idea of expanding during the round function from SSLeay */
32#ifdef WORDS_BIGENDIAN
33# define blk0(i) block->l[i]
34#else
35# define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
36 |(rol(block->l[i],8)&0x00FF00FF))
37#endif
38
39#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
40 ^block->l[(i+2)&15]^block->l[i&15],1))
41
42/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
43#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
44#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
45#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
46#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
47#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
48
49
50/* Hash a single 512-bit block. This is the core of the algorithm. */
51
52void SHA1Transform(uint32_t state[5], const unsigned char buffer[64])
53{
54uint32_t a, b, c, d, e;
55typedef union {
56 unsigned char c[64];
57 uint32_t l[16];
58} CHAR64LONG16;
59#ifdef SHA1HANDSOFF
60CHAR64LONG16 block[1]; /* use array to appear as a pointer */
61 memcpy(block, buffer, 64);
62#else
63 /* The following had better never be used because it causes the
64 * pointer-to-const buffer to be cast into a pointer to non-const.
65 * And the result is written through. I threw a "const" in, hoping
66 * this will cause a diagnostic.
67 */
68CHAR64LONG16* block = (const CHAR64LONG16*)buffer;
69#endif
70 /* Copy context->state[] to working vars */
71 a = state[0];
72 b = state[1];
73 c = state[2];
74 d = state[3];
75 e = state[4];
76 /* 4 rounds of 20 operations each. Loop unrolled. */
77 R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
78 R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
79 R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
80 R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
81 R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
82 R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
83 R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
84 R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
85 R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
86 R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
87 R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
88 R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
89 R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
90 R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
91 R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
92 R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
93 R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
94 R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
95 R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
96 R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
97 /* Add the working vars back into context.state[] */
98 state[0] += a;
99 state[1] += b;
100 state[2] += c;
101 state[3] += d;
102 state[4] += e;
103 /* Wipe variables */
104 a = b = c = d = e = 0;
105#ifdef SHA1HANDSOFF
106 memset(block, '\0', sizeof(block));
107#endif
108}
109
110
111/* SHA1Init - Initialize new context */
112
113void SHA1Init(SHA1_CTX* context)
114{
115 /* SHA1 initialization constants */
116 context->state[0] = 0x67452301;
117 context->state[1] = 0xEFCDAB89;
118 context->state[2] = 0x98BADCFE;
119 context->state[3] = 0x10325476;
120 context->state[4] = 0xC3D2E1F0;
121 context->count[0] = context->count[1] = 0;
122}
123
124
125/* Run your data through this. */
126
127void SHA1Update(SHA1_CTX* context, const unsigned char* data, uint32_t len)
128{
129uint32_t i;
130uint32_t j;
131
132 j = context->count[0];
133 if ((context->count[0] += len << 3) < j)
134 context->count[1]++;
135 context->count[1] += (len>>29);
136 j = (j >> 3) & 63;
137 if ((j + len) > 63) {
138 memcpy(&context->buffer[j], data, (i = 64-j));
139 SHA1Transform(context->state, context->buffer);
140 for ( ; i + 63 < len; i += 64) {
141 SHA1Transform(context->state, &data[i]);
142 }
143 j = 0;
144 }
145 else i = 0;
146 memcpy(&context->buffer[j], &data[i], len - i);
147}
148
149
150/* Add padding and return the message digest. */
151
152void SHA1Final(unsigned char digest[20], SHA1_CTX* context)
153{
154unsigned i;
155unsigned char finalcount[8];
156unsigned char c;
157
158#if 0 /* untested "improvement" by DHR */
159 /* Convert context->count to a sequence of bytes
160 * in finalcount. Second element first, but
161 * big-endian order within element.
162 * But we do it all backwards.
163 */
164 unsigned char *fcp = &finalcount[8];
165
166 for (i = 0; i < 2; i++)
167 {
168 uint32_t t = context->count[i];
169 int j;
170
171 for (j = 0; j < 4; t >>= 8, j++)
172 *--fcp = (unsigned char) t
173 }
174#else
175 for (i = 0; i < 8; i++) {
176 finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)]
177 >> ((3-(i & 3)) * 8) ) & 255); /* Endian independent */
178 }
179#endif
180 c = 0200;
181 SHA1Update(context, &c, 1);
182 while ((context->count[0] & 504) != 448) {
183 c = 0000;
184 SHA1Update(context, &c, 1);
185 }
186 SHA1Update(context, finalcount, 8); /* Should cause a SHA1Transform() */
187 for (i = 0; i < 20; i++) {
188 digest[i] = (unsigned char)
189 ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
190 }
191 /* Wipe variables */
192 memset(context, '\0', sizeof(*context));
193 memset(&finalcount, '\0', sizeof(finalcount));
194}