blob: 552dcad8070c964da147974f2607e24c31a33c9a [file] [log] [blame]
"Robert P. J. Day"63fc1a92006-07-02 19:47:05 +00001/* vi: set sw=4 ts=4: */
Rob Landley5cf7c2d2006-02-21 06:44:43 +00002/*
3 * Based on shasum from http://www.netsw.org/crypto/hash/
4 * Majorly hacked up to use Dr Brian Gladman's sha1 code
5 *
6 * Copyright (C) 2002 Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK.
7 * Copyright (C) 2003 Glenn L. McGrath
8 * Copyright (C) 2003 Erik Andersen
Denis Vlasenko9213a9e2006-09-17 16:28:10 +00009 *
"Robert P. J. Day"5d8843e2006-07-10 11:41:19 +000010 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
Rob Landley5cf7c2d2006-02-21 06:44:43 +000011 *
Rob Landley5cf7c2d2006-02-21 06:44:43 +000012 * ---------------------------------------------------------------------------
13 * Issue Date: 10/11/2002
14 *
15 * This is a byte oriented version of SHA1 that operates on arrays of bytes
16 * stored in memory. It runs at 22 cycles per byte on a Pentium P4 processor
17 */
18
Bernhard Reutner-Fischer421d9e52006-04-03 16:39:31 +000019#include "libbb.h"
Rob Landley5cf7c2d2006-02-21 06:44:43 +000020
Denis Vlasenko52417662006-09-28 00:29:00 +000021#define SHA1_BLOCK_SIZE 64
22#define SHA1_DIGEST_SIZE 20
23#define SHA1_HASH_SIZE SHA1_DIGEST_SIZE
24#define SHA2_GOOD 0
25#define SHA2_BAD 1
Rob Landley5cf7c2d2006-02-21 06:44:43 +000026
Denis Vlasenko52417662006-09-28 00:29:00 +000027#define rotl32(x,n) (((x) << n) | ((x) >> (32 - n)))
Rob Landley5cf7c2d2006-02-21 06:44:43 +000028
Denis Vlasenko52417662006-09-28 00:29:00 +000029#define SHA1_MASK (SHA1_BLOCK_SIZE - 1)
Rob Landley5cf7c2d2006-02-21 06:44:43 +000030
31/* reverse byte order in 32-bit words */
Denis Vlasenko52417662006-09-28 00:29:00 +000032#define ch(x,y,z) ((z) ^ ((x) & ((y) ^ (z))))
33#define parity(x,y,z) ((x) ^ (y) ^ (z))
34#define maj(x,y,z) (((x) & (y)) | ((z) & ((x) | (y))))
Rob Landley5cf7c2d2006-02-21 06:44:43 +000035
36/* A normal version as set out in the FIPS. This version uses */
37/* partial loop unrolling and is optimised for the Pentium 4 */
Denis Vlasenko52417662006-09-28 00:29:00 +000038#define rnd(f,k) \
39 do { \
40 t = a; a = rotl32(a,5) + f(b,c,d) + e + k + w[i]; \
41 e = d; d = c; c = rotl32(b, 30); b = t; \
Denis Vlasenkobf0a2012006-12-26 10:42:51 +000042 } while (0)
Rob Landley5cf7c2d2006-02-21 06:44:43 +000043
44static void sha1_compile(sha1_ctx_t *ctx)
45{
46 uint32_t w[80], i, a, b, c, d, e, t;
47
48 /* note that words are compiled from the buffer into 32-bit */
49 /* words in big-endian order so an order reversal is needed */
50 /* here on little endian machines */
51 for (i = 0; i < SHA1_BLOCK_SIZE / 4; ++i)
52 w[i] = htonl(ctx->wbuf[i]);
53
54 for (i = SHA1_BLOCK_SIZE / 4; i < 80; ++i)
55 w[i] = rotl32(w[i - 3] ^ w[i - 8] ^ w[i - 14] ^ w[i - 16], 1);
56
57 a = ctx->hash[0];
58 b = ctx->hash[1];
59 c = ctx->hash[2];
60 d = ctx->hash[3];
61 e = ctx->hash[4];
62
63 for (i = 0; i < 20; ++i) {
64 rnd(ch, 0x5a827999);
65 }
66
67 for (i = 20; i < 40; ++i) {
68 rnd(parity, 0x6ed9eba1);
69 }
70
71 for (i = 40; i < 60; ++i) {
72 rnd(maj, 0x8f1bbcdc);
73 }
74
75 for (i = 60; i < 80; ++i) {
76 rnd(parity, 0xca62c1d6);
77 }
78
79 ctx->hash[0] += a;
80 ctx->hash[1] += b;
81 ctx->hash[2] += c;
82 ctx->hash[3] += d;
83 ctx->hash[4] += e;
84}
85
86void sha1_begin(sha1_ctx_t *ctx)
87{
88 ctx->count[0] = ctx->count[1] = 0;
89 ctx->hash[0] = 0x67452301;
90 ctx->hash[1] = 0xefcdab89;
91 ctx->hash[2] = 0x98badcfe;
92 ctx->hash[3] = 0x10325476;
93 ctx->hash[4] = 0xc3d2e1f0;
94}
95
96/* SHA1 hash data in an array of bytes into hash buffer and call the */
97/* hash_compile function as required. */
98void sha1_hash(const void *data, size_t length, sha1_ctx_t *ctx)
99{
100 uint32_t pos = (uint32_t) (ctx->count[0] & SHA1_MASK);
101 uint32_t freeb = SHA1_BLOCK_SIZE - pos;
102 const unsigned char *sp = data;
103
104 if ((ctx->count[0] += length) < length)
105 ++(ctx->count[1]);
106
107 while (length >= freeb) { /* tranfer whole blocks while possible */
108 memcpy(((unsigned char *) ctx->wbuf) + pos, sp, freeb);
109 sp += freeb;
110 length -= freeb;
111 freeb = SHA1_BLOCK_SIZE;
112 pos = 0;
113 sha1_compile(ctx);
114 }
115
116 memcpy(((unsigned char *) ctx->wbuf) + pos, sp, length);
117}
118
119void *sha1_end(void *resbuf, sha1_ctx_t *ctx)
120{
121 /* SHA1 Final padding and digest calculation */
Mike Frysingerf8855132006-03-28 02:35:56 +0000122#if BB_BIG_ENDIAN
123 static uint32_t mask[4] = { 0x00000000, 0xff000000, 0xffff0000, 0xffffff00 };
124 static uint32_t bits[4] = { 0x80000000, 0x00800000, 0x00008000, 0x00000080 };
125#else
126 static uint32_t mask[4] = { 0x00000000, 0x000000ff, 0x0000ffff, 0x00ffffff };
127 static uint32_t bits[4] = { 0x00000080, 0x00008000, 0x00800000, 0x80000000 };
Rob Landley2c39eee2006-05-05 16:54:40 +0000128#endif
Rob Landley5cf7c2d2006-02-21 06:44:43 +0000129
130 uint8_t *hval = resbuf;
131 uint32_t i, cnt = (uint32_t) (ctx->count[0] & SHA1_MASK);
132
133 /* mask out the rest of any partial 32-bit word and then set */
134 /* the next byte to 0x80. On big-endian machines any bytes in */
135 /* the buffer will be at the top end of 32 bit words, on little */
136 /* endian machines they will be at the bottom. Hence the AND */
137 /* and OR masks above are reversed for little endian systems */
138 ctx->wbuf[cnt >> 2] =
139 (ctx->wbuf[cnt >> 2] & mask[cnt & 3]) | bits[cnt & 3];
140
141 /* we need 9 or more empty positions, one for the padding byte */
142 /* (above) and eight for the length count. If there is not */
143 /* enough space pad and empty the buffer */
144 if (cnt > SHA1_BLOCK_SIZE - 9) {
145 if (cnt < 60)
146 ctx->wbuf[15] = 0;
147 sha1_compile(ctx);
148 cnt = 0;
149 } else /* compute a word index for the empty buffer positions */
150 cnt = (cnt >> 2) + 1;
151
152 while (cnt < 14) /* and zero pad all but last two positions */
153 ctx->wbuf[cnt++] = 0;
154
155 /* assemble the eight byte counter in the buffer in big-endian */
Denis Vlasenko52417662006-09-28 00:29:00 +0000156 /* format */
Rob Landley5cf7c2d2006-02-21 06:44:43 +0000157
158 ctx->wbuf[14] = htonl((ctx->count[1] << 3) | (ctx->count[0] >> 29));
159 ctx->wbuf[15] = htonl(ctx->count[0] << 3);
160
161 sha1_compile(ctx);
162
163 /* extract the hash value as bytes in case the hash buffer is */
164 /* misaligned for 32-bit words */
165
166 for (i = 0; i < SHA1_DIGEST_SIZE; ++i)
167 hval[i] = (unsigned char) (ctx->hash[i >> 2] >> 8 * (~i & 3));
Denis Vlasenko9213a9e2006-09-17 16:28:10 +0000168
Rob Landley5cf7c2d2006-02-21 06:44:43 +0000169 return resbuf;
170}