summaryrefslogtreecommitdiff
path: root/lib/crc32.c
blob: 7f545fde4a0225c5b7614942f5839d99e5f8e784 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
/*
 * This file is derived from crc32.c from the zlib-1.1.3 distribution
 * by Jean-loup Gailly and Mark Adler.
 */

/* crc32.c -- compute the CRC-32 of a data stream
 * Copyright (C) 1995-1998 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

#ifdef USE_HOSTCC
#include <arpa/inet.h>
#else
#include <common.h>
#endif
#include <compiler.h>
#include <u-boot/crc.h>

#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
#include <watchdog.h>
#endif
#include "u-boot/zlib.h"

#define local static
#define ZEXPORT	/* empty */

#define tole(x) cpu_to_le32(x)

#ifdef CONFIG_DYNAMIC_CRC_TABLE

local int crc_table_empty = 1;
local uint32_t crc_table[256];
local void make_crc_table OF((void));

/*
  Generate a table for a byte-wise 32-bit CRC calculation on the polynomial:
  x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.

  Polynomials over GF(2) are represented in binary, one bit per coefficient,
  with the lowest powers in the most significant bit.  Then adding polynomials
  is just exclusive-or, and multiplying a polynomial by x is a right shift by
  one.  If we call the above polynomial p, and represent a byte as the
  polynomial q, also with the lowest power in the most significant bit (so the
  byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
  where a mod b means the remainder after dividing a by b.

  This calculation is done using the shift-register method of multiplying and
  taking the remainder.  The register is initialized to zero, and for each
  incoming bit, x^32 is added mod p to the register if the bit is a one (where
  x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
  x (which is shifting right by one and adding x^32 mod p if the bit shifted
  out is a one).  We start with the highest power (least significant bit) of
  q and repeat for all eight bits of q.

  The table is simply the CRC of all possible eight bit values.  This is all
  the information needed to generate CRC's on data a byte at a time for all
  combinations of CRC register values and incoming bytes.
*/
local void make_crc_table()
{
  uint32_t c;
  int n, k;
  uLong poly;		/* polynomial exclusive-or pattern */
  /* terms of polynomial defining this crc (except x^32): */
  static const Byte p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};

  /* make exclusive-or pattern from polynomial (0xedb88320L) */
  poly = 0L;
  for (n = 0; n < sizeof(p)/sizeof(Byte); n++)
    poly |= 1L << (31 - p[n]);

  for (n = 0; n < 256; n++)
  {
    c = (uLong)n;
    for (k = 0; k < 8; k++)
      c = c & 1 ? poly ^ (c >> 1) : c >> 1;
    crc_table[n] = tole(c);
  }
  crc_table_empty = 0;
}
#else
/* ========================================================================
 * Table of CRC-32's of all single-byte values (made by make_crc_table)
 */

local const uint32_t crc_table[256] = {
tole(0x00000000L), tole(0x77073096L), tole(0xee0e612cL), tole(0x990951baL),
tole(0x076dc419L), tole(0x706af48fL), tole(0xe963a535L), tole(0x9e6495a3L),
tole(0x0edb8832L), tole(0x79dcb8a4L), tole(0xe0d5e91eL), tole(0x97d2d988L),
tole(0x09b64c2bL), tole(0x7eb17cbdL), tole(0xe7b82d07L), tole(0x90bf1d91L),
tole(0x1db71064L), tole(0x6ab020f2L), tole(0xf3b97148L), tole(0x84be41deL),
tole(0x1adad47dL), tole(0x6ddde4ebL), tole(0xf4d4b551L), tole(0x83d385c7L),
tole(0x136c9856L), tole(0x646ba8c0L), tole(0xfd62f97aL), tole(0x8a65c9ecL),
tole(0x14015c4fL), tole(0x63066cd9L), tole(0xfa0f3d63L), tole(0x8d080df5L),
tole(0x3b6e20c8L), tole(0x4c69105eL), tole(0xd56041e4L), tole(0xa2677172L),
tole(0x3c03e4d1L), tole(0x4b04d447L), tole(0xd20d85fdL), tole(0xa50ab56bL),
tole(0x35b5a8faL), tole(0x42b2986cL), tole(0xdbbbc9d6L), tole(0xacbcf940L),
tole(0x32d86ce3L), tole(0x45df5c75L), tole(0xdcd60dcfL), tole(0xabd13d59L),
tole(0x26d930acL), tole(0x51de003aL), tole(0xc8d75180L), tole(0xbfd06116L),
tole(0x21b4f4b5L), tole(0x56b3c423L), tole(0xcfba9599L), tole(0xb8bda50fL),
tole(0x2802b89eL), tole(0x5f058808L), tole(0xc60cd9b2L), tole(0xb10be924L),
tole(0x2f6f7c87L), tole(0x58684c11L), tole(0xc1611dabL), tole(0xb6662d3dL),
tole(0x76dc4190L), tole(0x01db7106L), tole(0x98d220bcL), tole(0xefd5102aL),
tole(0x71b18589L), tole(0x06b6b51fL), tole(0x9fbfe4a5L), tole(0xe8b8d433L),
tole(0x7807c9a2L), tole(0x0f00f934L), tole(0x9609a88eL), tole(0xe10e9818L),
tole(0x7f6a0dbbL), tole(0x086d3d2dL), tole(0x91646c97L), tole(0xe6635c01L),
tole(0x6b6b51f4L), tole(0x1c6c6162L), tole(0x856530d8L), tole(0xf262004eL),
tole(0x6c0695edL), tole(0x1b01a57bL), tole(0x8208f4c1L), tole(0xf50fc457L),
tole(0x65b0d9c6L), tole(0x12b7e950L), tole(0x8bbeb8eaL), tole(0xfcb9887cL),
tole(0x62dd1ddfL), tole(0x15da2d49L), tole(0x8cd37cf3L), tole(0xfbd44c65L),
tole(0x4db26158L), tole(0x3ab551ceL), tole(0xa3bc0074L), tole(0xd4bb30e2L),
tole(0x4adfa541L), tole(0x3dd895d7L), tole(0xa4d1c46dL), tole(0xd3d6f4fbL),
tole(0x4369e96aL), tole(0x346ed9fcL), tole(0xad678846L), tole(0xda60b8d0L),
tole(0x44042d73L), tole(0x33031de5L), tole(0xaa0a4c5fL), tole(0xdd0d7cc9L),
tole(0x5005713cL), tole(0x270241aaL), tole(0xbe0b1010L), tole(0xc90c2086L),
tole(0x5768b525L), tole(0x206f85b3L), tole(0xb966d409L), tole(0xce61e49fL),
tole(0x5edef90eL), tole(0x29d9c998L), tole(0xb0d09822L), tole(0xc7d7a8b4L),
tole(0x59b33d17L), tole(0x2eb40d81L), tole(0xb7bd5c3bL), tole(0xc0ba6cadL),
tole(0xedb88320L), tole(0x9abfb3b6L), tole(0x03b6e20cL), tole(0x74b1d29aL),
tole(0xead54739L), tole(0x9dd277afL), tole(0x04db2615L), tole(0x73dc1683L),
tole(0xe3630b12L), tole(0x94643b84L), tole(0x0d6d6a3eL), tole(0x7a6a5aa8L),
tole(0xe40ecf0bL), tole(0x9309ff9dL), tole(0x0a00ae27L), tole(0x7d079eb1L),
tole(0xf00f9344L), tole(0x8708a3d2L), tole(0x1e01f268L), tole(0x6906c2feL),
tole(0xf762575dL), tole(0x806567cbL), tole(0x196c3671L), tole(0x6e6b06e7L),
tole(0xfed41b76L), tole(0x89d32be0L), tole(0x10da7a5aL), tole(0x67dd4accL),
tole(0xf9b9df6fL), tole(0x8ebeeff9L), tole(0x17b7be43L), tole(0x60b08ed5L),
tole(0xd6d6a3e8L), tole(0xa1d1937eL), tole(0x38d8c2c4L), tole(0x4fdff252L),
tole(0xd1bb67f1L), tole(0xa6bc5767L), tole(0x3fb506ddL), tole(0x48b2364bL),
tole(0xd80d2bdaL), tole(0xaf0a1b4cL), tole(0x36034af6L), tole(0x41047a60L),
tole(0xdf60efc3L), tole(0xa867df55L), tole(0x316e8eefL), tole(0x4669be79L),
tole(0xcb61b38cL), tole(0xbc66831aL), tole(0x256fd2a0L), tole(0x5268e236L),
tole(0xcc0c7795L), tole(0xbb0b4703L), tole(0x220216b9L), tole(0x5505262fL),
tole(0xc5ba3bbeL), tole(0xb2bd0b28L), tole(0x2bb45a92L), tole(0x5cb36a04L),
tole(0xc2d7ffa7L), tole(0xb5d0cf31L), tole(0x2cd99e8bL), tole(0x5bdeae1dL),
tole(0x9b64c2b0L), tole(0xec63f226L), tole(0x756aa39cL), tole(0x026d930aL),
tole(0x9c0906a9L), tole(0xeb0e363fL), tole(0x72076785L), tole(0x05005713L),
tole(0x95bf4a82L), tole(0xe2b87a14L), tole(0x7bb12baeL), tole(0x0cb61b38L),
tole(0x92d28e9bL), tole(0xe5d5be0dL), tole(0x7cdcefb7L), tole(0x0bdbdf21L),
tole(0x86d3d2d4L), tole(0xf1d4e242L), tole(0x68ddb3f8L), tole(0x1fda836eL),
tole(0x81be16cdL), tole(0xf6b9265bL), tole(0x6fb077e1L), tole(0x18b74777L),
tole(0x88085ae6L), tole(0xff0f6a70L), tole(0x66063bcaL), tole(0x11010b5cL),
tole(0x8f659effL), tole(0xf862ae69L), tole(0x616bffd3L), tole(0x166ccf45L),
tole(0xa00ae278L), tole(0xd70dd2eeL), tole(0x4e048354L), tole(0x3903b3c2L),
tole(0xa7672661L), tole(0xd06016f7L), tole(0x4969474dL), tole(0x3e6e77dbL),
tole(0xaed16a4aL), tole(0xd9d65adcL), tole(0x40df0b66L), tole(0x37d83bf0L),
tole(0xa9bcae53L), tole(0xdebb9ec5L), tole(0x47b2cf7fL), tole(0x30b5ffe9L),
tole(0xbdbdf21cL), tole(0xcabac28aL), tole(0x53b39330L), tole(0x24b4a3a6L),
tole(0xbad03605L), tole(0xcdd70693L), tole(0x54de5729L), tole(0x23d967bfL),
tole(0xb3667a2eL), tole(0xc4614ab8L), tole(0x5d681b02L), tole(0x2a6f2b94L),
tole(0xb40bbe37L), tole(0xc30c8ea1L), tole(0x5a05df1bL), tole(0x2d02ef8dL)
};
#endif

#if 0
/* =========================================================================
 * This function can be used by asm versions of crc32()
 */
const uint32_t * ZEXPORT get_crc_table()
{
#ifdef CONFIG_DYNAMIC_CRC_TABLE
  if (crc_table_empty) make_crc_table();
#endif
  return (const uint32_t *)crc_table;
}
#endif

/* ========================================================================= */
# if __BYTE_ORDER == __LITTLE_ENDIAN
#  define DO_CRC(x) crc = tab[(crc ^ (x)) & 255] ^ (crc >> 8)
# else
#  define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8)
# endif

/* ========================================================================= */

/* No ones complement version. JFFS2 (and other things ?)
 * don't use ones compliment in their CRC calculations.
 */
uint32_t ZEXPORT crc32_no_comp(uint32_t crc, const Bytef *buf, uInt len)
{
    const uint32_t *tab = crc_table;
    const uint32_t *b =(const uint32_t *)buf;
    size_t rem_len;
#ifdef CONFIG_DYNAMIC_CRC_TABLE
    if (crc_table_empty)
      make_crc_table();
#endif
    crc = cpu_to_le32(crc);
    /* Align it */
    if (((long)b) & 3 && len) {
	 uint8_t *p = (uint8_t *)b;
	 do {
	      DO_CRC(*p++);
	 } while ((--len) && ((long)p)&3);
	 b = (uint32_t *)p;
    }

    rem_len = len & 3;
    len = len >> 2;
    for (--b; len; --len) {
	 /* load data 32 bits wide, xor data 32 bits wide. */
	 crc ^= *++b; /* use pre increment for speed */
	 DO_CRC(0);
	 DO_CRC(0);
	 DO_CRC(0);
	 DO_CRC(0);
    }
    len = rem_len;
    /* And the last few bytes */
    if (len) {
	 uint8_t *p = (uint8_t *)(b + 1) - 1;
	 do {
	      DO_CRC(*++p); /* use pre increment for speed */
	 } while (--len);
    }

    return le32_to_cpu(crc);
}
#undef DO_CRC

uint32_t ZEXPORT crc32 (uint32_t crc, const Bytef *p, uInt len)
{
     return crc32_no_comp(crc ^ 0xffffffffL, p, len) ^ 0xffffffffL;
}

/*
 * Calculate the crc32 checksum triggering the watchdog every 'chunk_sz' bytes
 * of input.
 */
uint32_t ZEXPORT crc32_wd (uint32_t crc,
			   const unsigned char *buf,
			   uInt len, uInt chunk_sz)
{
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
	const unsigned char *end, *curr;
	int chunk;

	curr = buf;
	end = buf + len;
	while (curr < end) {
		chunk = end - curr;
		if (chunk > chunk_sz)
			chunk = chunk_sz;
		crc = crc32 (crc, curr, chunk);
		curr += chunk;
		WATCHDOG_RESET ();
	}
#else
	crc = crc32 (crc, buf, len);
#endif

	return crc;
}

void crc32_wd_buf(const unsigned char *input, unsigned int ilen,
		unsigned char *output, unsigned int chunk_sz)
{
	uint32_t crc;

	crc = crc32_wd(0, input, ilen, chunk_sz);
	crc = htonl(crc);
	memcpy(output, &crc, sizeof(crc));
}