block-sha1: guard gcc extensions with __GNUC__
[git/git.git] / arm / sha1.c
1 /*
2 * SHA-1 implementation optimized for ARM
3 *
4 * Copyright: (C) 2005 by Nicolas Pitre <nico@cam.org>
5 * Created: September 17, 2005
6 */
7
8 #include <string.h>
9 #include "sha1.h"
10
11 extern void arm_sha_transform(uint32_t *hash, const unsigned char *data, uint32_t *W);
12
13 void arm_SHA1_Init(arm_SHA_CTX *c)
14 {
15 c->len = 0;
16 c->hash[0] = 0x67452301;
17 c->hash[1] = 0xefcdab89;
18 c->hash[2] = 0x98badcfe;
19 c->hash[3] = 0x10325476;
20 c->hash[4] = 0xc3d2e1f0;
21 }
22
23 void arm_SHA1_Update(arm_SHA_CTX *c, const void *p, unsigned long n)
24 {
25 uint32_t workspace[80];
26 unsigned int partial;
27 unsigned long done;
28
29 partial = c->len & 0x3f;
30 c->len += n;
31 if ((partial + n) >= 64) {
32 if (partial) {
33 done = 64 - partial;
34 memcpy(c->buffer + partial, p, done);
35 arm_sha_transform(c->hash, c->buffer, workspace);
36 partial = 0;
37 } else
38 done = 0;
39 while (n >= done + 64) {
40 arm_sha_transform(c->hash, p + done, workspace);
41 done += 64;
42 }
43 } else
44 done = 0;
45 if (n - done)
46 memcpy(c->buffer + partial, p + done, n - done);
47 }
48
49 void arm_SHA1_Final(unsigned char *hash, arm_SHA_CTX *c)
50 {
51 uint64_t bitlen;
52 uint32_t bitlen_hi, bitlen_lo;
53 unsigned int i, offset, padlen;
54 unsigned char bits[8];
55 static const unsigned char padding[64] = { 0x80, };
56
57 bitlen = c->len << 3;
58 offset = c->len & 0x3f;
59 padlen = ((offset < 56) ? 56 : (64 + 56)) - offset;
60 arm_SHA1_Update(c, padding, padlen);
61
62 bitlen_hi = bitlen >> 32;
63 bitlen_lo = bitlen & 0xffffffff;
64 bits[0] = bitlen_hi >> 24;
65 bits[1] = bitlen_hi >> 16;
66 bits[2] = bitlen_hi >> 8;
67 bits[3] = bitlen_hi;
68 bits[4] = bitlen_lo >> 24;
69 bits[5] = bitlen_lo >> 16;
70 bits[6] = bitlen_lo >> 8;
71 bits[7] = bitlen_lo;
72 arm_SHA1_Update(c, bits, 8);
73
74 for (i = 0; i < 5; i++) {
75 uint32_t v = c->hash[i];
76 hash[0] = v >> 24;
77 hash[1] = v >> 16;
78 hash[2] = v >> 8;
79 hash[3] = v;
80 hash += 4;
81 }
82 }