1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
10 #include <unistd.h> /* for unlink() */
12 #include <getopt.h> /* for getopt() */
17 #if (__BYTE_ORDER == __LITTLE_ENDIAN)
18 # define HOST_TO_LE16(x) (x)
19 # define HOST_TO_LE32(x) (x)
20 # define LE16_TO_HOST(x) (x)
21 # define LE32_TO_HOST(x) (x)
23 # define HOST_TO_LE16(x) bswap_16(x)
24 # define HOST_TO_LE32(x) bswap_32(x)
25 # define LE16_TO_HOST(x) bswap_16(x)
26 # define LE32_TO_HOST(x) bswap_32(x)
29 uint32_t crc32buf(char *buf
, size_t len
);
35 static char *progname
;
41 #define ERR(fmt, ...) do { \
43 fprintf(stderr, "[%s] *** error: " fmt "\n", \
44 progname, ## __VA_ARGS__ ); \
47 #define ERRS(fmt, ...) do { \
50 fprintf(stderr, "[%s] *** error: " fmt ": %s\n", \
51 progname, ## __VA_ARGS__, strerror(save)); \
54 void usage(int status
)
56 FILE *stream
= (status
!= EXIT_SUCCESS
) ? stderr
: stdout
;
58 fprintf(stream
, "Usage: %s [OPTIONS...]\n", progname
);
62 " -i <file> read input from the file <file>\n"
63 " -o <file> write output to the file <file>\n"
64 " -h show this screen\n"
70 int main(int argc
, char *argv
[])
72 int res
= EXIT_FAILURE
;
80 FILE *outfile
, *infile
;
82 progname
= basename(argv
[0]);
87 c
= getopt(argc
, argv
, "i:o:h");
107 if (ifname
== NULL
) {
108 ERR("no input file specified");
112 if (ofname
== NULL
) {
113 ERR("no output file specified");
117 err
= stat(ifname
, &st
);
119 ERRS("stat failed on %s", ifname
);
124 buf
= malloc(buflen
);
126 ERR("no memory for buffer\n");
130 infile
= fopen(ifname
, "r");
131 if (infile
== NULL
) {
132 ERRS("could not open \"%s\" for reading", ifname
);
137 fread(buf
, buflen
, 1, infile
);
139 ERRS("unable to read from file %s", ifname
);
143 crc
= crc32buf(buf
, buflen
);
144 hdr
= (uint32_t *)buf
;
145 *hdr
= HOST_TO_LE32(crc
);
147 outfile
= fopen(ofname
, "w");
148 if (outfile
== NULL
) {
149 ERRS("could not open \"%s\" for writing", ofname
);
154 fwrite(buf
, buflen
, 1, outfile
);
156 ERRS("unable to write to file %s", ofname
);
166 if (res
!= EXIT_SUCCESS
) {
180 /**********************************************************************/
181 /* The following was grabbed and tweaked from the old snippets collection
182 * of public domain C code. */
184 /**********************************************************************\
185 |* Demonstration program to compute the 32-bit CRC used as the frame *|
186 |* check sequence in ADCCP (ANSI X3.66, also known as FIPS PUB 71 *|
187 |* and FED-STD-1003, the U.S. versions of CCITT's X.25 link-level *|
188 |* protocol). The 32-bit FCS was added via the Federal Register, *|
189 |* 1 June 1982, p.23798. I presume but don't know for certain that *|
190 |* this polynomial is or will be included in CCITT V.41, which *|
191 |* defines the 16-bit CRC (often called CRC-CCITT) polynomial. FIPS *|
192 |* PUB 78 says that the 32-bit FCS reduces otherwise undetected *|
193 |* errors by a factor of 10^-5 over 16-bit FCS. *|
194 \**********************************************************************/
196 /* Copyright (C) 1986 Gary S. Brown. You may use this program, or
197 code or tables extracted from it, as desired without restriction.*/
199 /* First, the polynomial itself and its table of feedback terms. The */
201 /* 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+X^0 */
202 /* Note that we take it "backwards" and put the highest-order term in */
203 /* the lowest-order bit. The X^32 term is "implied"; the LSB is the */
204 /* X^31 term, etc. The X^0 term (usually shown as "+1") results in */
205 /* the MSB being 1. */
207 /* Note that the usual hardware shift register implementation, which */
208 /* is what we're using (we're merely optimizing it by doing eight-bit */
209 /* chunks at a time) shifts bits into the lowest-order term. In our */
210 /* implementation, that means shifting towards the right. Why do we */
211 /* do it this way? Because the calculated CRC must be transmitted in */
212 /* order from highest-order term to lowest-order term. UARTs transmit */
213 /* characters in order from LSB to MSB. By storing the CRC this way, */
214 /* we hand it to the UART in the order low-byte to high-byte; the UART */
215 /* sends each low-bit to hight-bit; and the result is transmission bit */
216 /* by bit from highest- to lowest-order term without requiring any bit */
217 /* shuffling on our part. Reception works similarly. */
219 /* The feedback terms table consists of 256, 32-bit entries. Notes: */
221 /* 1. The table can be generated at runtime if desired; code to do so */
222 /* is shown later. It might not be obvious, but the feedback */
223 /* terms simply represent the results of eight shift/xor opera- */
224 /* tions for all combinations of data and CRC register values. */
226 /* 2. The CRC accumulation logic is the same for all CRC polynomials, */
227 /* be they sixteen or thirty-two bits wide. You simply choose the */
228 /* appropriate table. Alternatively, because the table can be */
229 /* generated at runtime, you can start by generating the table for */
230 /* the polynomial in question and use exactly the same "updcrc", */
231 /* if your application needn't simultaneously handle two CRC */
232 /* polynomials. (Note, however, that XMODEM is strange.) */
234 /* 3. For 16-bit CRCs, the table entries need be only 16 bits wide; */
235 /* of course, 32-bit entries work OK if the high 16 bits are zero. */
237 /* 4. The values must be right-shifted by eight bits by the "updcrc" */
238 /* logic; the shift must be unsigned (bring in zeroes). On some */
239 /* hardware you could probably optimize the shift in assembler by */
240 /* using byte-swap instructions. */
242 static const uint32_t crc_32_tab
[] = { /* CRC polynomial 0xedb88320 */
243 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
244 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
245 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
246 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
247 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
248 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
249 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
250 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
251 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
252 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
253 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
254 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
255 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
256 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
257 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
258 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
259 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
260 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
261 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
262 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
263 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
264 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
265 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
266 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
267 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
268 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
269 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
270 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
271 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
272 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
273 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
274 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
275 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
276 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
277 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
278 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
279 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
280 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
281 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
282 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
283 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
284 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
285 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
288 #define UPDC32(octet,crc) (crc_32_tab[((crc) ^ (octet)) & 0xff] ^ ((crc) >> 8))
290 uint32_t crc32buf(char *buf
, size_t len
)
296 for ( ; len
; --len
, ++buf
)
298 crc
= UPDC32(*buf
, crc
);
301 return crc
^ 0xFFFFFFFF;