1: /*************************************************************************
2: * (C) 2008 AITNET ltd - Sofia/Bulgaria - <misho@aitbg.com>
3: * by Michael Pounov <misho@openbsd-bg.org>
4: *
5: * $Author: misho $
6: * $Id: aitcrc.c,v 1.4.2.3 2012/07/04 14:46:33 misho Exp $
7: *
8: **************************************************************************
9: The ELWIX and AITNET software is distributed under the following
10: terms:
11:
12: All of the documentation and software included in the ELWIX and AITNET
13: Releases is copyrighted by ELWIX - Sofia/Bulgaria <info@elwix.org>
14:
15: Copyright 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
16: by Michael Pounov <misho@elwix.org>. All rights reserved.
17:
18: Redistribution and use in source and binary forms, with or without
19: modification, are permitted provided that the following conditions
20: are met:
21: 1. Redistributions of source code must retain the above copyright
22: notice, this list of conditions and the following disclaimer.
23: 2. Redistributions in binary form must reproduce the above copyright
24: notice, this list of conditions and the following disclaimer in the
25: documentation and/or other materials provided with the distribution.
26: 3. All advertising materials mentioning features or use of this software
27: must display the following acknowledgement:
28: This product includes software developed by Michael Pounov <misho@elwix.org>
29: ELWIX - Embedded LightWeight unIX and its contributors.
30: 4. Neither the name of AITNET nor the names of its contributors
31: may be used to endorse or promote products derived from this software
32: without specific prior written permission.
33:
34: THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``AS IS'' AND
35: ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
36: IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
37: ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
38: FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
39: DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
40: OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
41: HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
42: LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
43: OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
44: SUCH DAMAGE.
45: */
46: #include "global.h"
47:
48:
49: static int crc_Errno;
50: static char crc_Error[MAX_STR + 1];
51:
52: /* Adler module */
53: const u_int crc_modAdler = 0xFFF1L;
54:
55: /* All known library CRC types ... */
56: const crcPoly_t crc_Poly[] = {
57: { 1, (u_int) 0x1, "CRC-1-Parity" },
58: { 4, (u_int) 0x3, "CRC-4-ITU" },
59: { 5, (u_int) 0x15, "CRC-5-ITU" },
60: { 6, (u_int) 0x3, "CRC-6-ITU" },
61: { 7, (u_int) 0x9, "CRC-7-MMC" },
62: { 8, (u_int) 0x8D, "CRC-8-CCITT" },
63: { 10, (u_int) 0x233, "CRC-10" },
64: { 11, (u_int) 0x385, "CRC-11-FlexRay" },
65: { 12, (u_int) 0x80F, "CRC-12-Telco" },
66: { 15, (u_int) 0x4599, "CRC-15-CAN" },
67: { 16, (u_int) 0x8005, "CRC-16-IBM" },
68: { 24, (u_int) 0x864CFB, "CRC-24-Radix64" },
69: { 30, (u_int) 0x2030B9C7, "CRC-30-CDMA" },
70: { 32, (u_int) 0x04C11DB7, "CRC-32-802.3" }
71: };
72:
73:
74: /*
75: * Error maintenance functions ...
76: */
77:
78: /* crc_GetErrno() Get error code of last operation */
79: inline int
80: crc_GetErrno()
81: {
82: return crc_Errno;
83: }
84:
85: /* crc_GetError() Get error text of last operation */
86: inline const char *
87: crc_GetError()
88: {
89: return crc_Error;
90: }
91:
92: /* crc_SetErr() Set error to variables for internal use!!! */
93: inline void
94: crc_SetErr(int eno, char *estr, ...)
95: {
96: va_list lst;
97:
98: crc_Errno = eno;
99: memset(crc_Error, 0, sizeof crc_Error);
100: va_start(lst, estr);
101: vsnprintf(crc_Error, sizeof crc_Error, estr, lst);
102: va_end(lst);
103: }
104:
105:
106: /*
107: * crcReflect() - Reflect all bits of number
108: *
109: * @crcNum = Number for reflection
110: * @crcBits = Number width bits
111: * return: -1 error, !=-1 reflecting number
112: */
113: inline u_int
114: crcReflect(u_int crcNum, u_char crcBits)
115: {
116: register u_int i, j, rev;
117:
118: for (i = (u_int) 1 << (crcBits - 1), j = 1, rev ^= rev; i; i >>= 1, j <<= 1)
119: if (crcNum & i)
120: rev |= j;
121:
122: crc_Errno ^= crc_Errno;
123: return rev;
124: }
125:
126: /*
127: * crcCalc() - Generic CRC calculation function for many sub variants of CRC algorithms
128: *
129: * @psBuf = Data for calculation
130: * @bufLen = Length of data
131: * @crcBits = CRC algorithm bits (1, 4, 5, 6, 7, 8, 10, 11, 12, 15, 16, 24, 30, 32)
132: * @RevOpts = Options for computation (REVOPTS_REVERTBYTE, REVOPTS_REVERTCRC)
133: * @initCRC = Initial CRC value
134: * @xorCRC = Last xor CRC value
135: * return: -1 error, !=-1 CRC checksum
136: */
137: inline u_int
138: crcCalc(u_char * __restrict psBuf, u_int bufLen, u_char crcBits, u_char RevOpts, u_int initCRC, u_int xorCRC)
139: {
140: const u_int bits = sizeof(int) * 8 - crcBits;
141: u_int poly, crchibit, crc;
142: register u_int i, j, b, ch;
143:
144: if (!psBuf) {
145: crc_SetErr(EINVAL, "Invalid parameters!");
146: return -1;
147: }
148:
149: switch (crcBits) {
150: case 1:
151: poly = crc_Poly[0].poly_num;
152: break;
153: case 4:
154: poly = crc_Poly[1].poly_num;
155: break;
156: case 5:
157: poly = crc_Poly[2].poly_num;
158: break;
159: case 6:
160: poly = crc_Poly[3].poly_num;
161: break;
162: case 7:
163: poly = crc_Poly[4].poly_num;
164: break;
165: case 8:
166: poly = crc_Poly[5].poly_num;
167: break;
168: case 10:
169: poly = crc_Poly[6].poly_num;
170: break;
171: case 11:
172: poly = crc_Poly[7].poly_num;
173: break;
174: case 12:
175: poly = crc_Poly[8].poly_num;
176: break;
177: case 15:
178: poly = crc_Poly[9].poly_num;
179: break;
180: case 16:
181: poly = crc_Poly[10].poly_num;
182: break;
183: case 24:
184: poly = crc_Poly[11].poly_num;
185: break;
186: case 30:
187: poly = crc_Poly[12].poly_num;
188: break;
189: case 32:
190: poly = crc_Poly[13].poly_num;
191: break;
192: default:
193: crc_SetErr(EINVAL, "crcCalc(): Unsupported CRC method!!!");
194: return -1;
195: }
196: poly <<= bits;
197:
198: crchibit = (u_int) 1 << (crcBits - 1);
199: crchibit <<= bits;
200: crc = initCRC << bits;
201:
202: for (i = 0; i < bufLen; i++) {
203: ch = (u_int) *psBuf++;
204: if (RevOpts & REVOPTS_REVERTBYTE)
205: ch = crcReflect(ch, 8);
206:
207: for (j = 0x80; j; j >>= 1) {
208: b = crc & crchibit;
209: crc <<= 1;
210:
211: if (ch & j)
212: b ^= crchibit;
213: if (b)
214: crc ^= poly;
215: }
216: }
217:
218: if (RevOpts & REVOPTS_REVERTCRC)
219: crc = crcReflect(crc, sizeof(int) * 8);
220: crc ^= xorCRC << bits;
221: crc &= (((crchibit - 1) << 1) | 1);
222: if (!(RevOpts & REVOPTS_REVERTCRC))
223: crc >>= bits;
224:
225: crc_Errno ^= crc_Errno;
226: return crc;
227: }
228:
229:
230: /*
231: * crcIP() - Checksum in IP communication
232: *
233: * @buf = Data for calculation
234: * @bufLen = Length of data
235: * return: -1 error, !=-1 Checksum
236: */
237: inline u_short
238: crcIP(u_char * __restrict buf, int bufLen)
239: {
240: register u_int sum;
241: u_short last = 0, *nBuf = (u_short*) buf;
242:
243: if (!buf) {
244: crc_SetErr(EINVAL, "Invalid parameters!");
245: return -1;
246: }
247:
248: for (sum = 0; bufLen && bufLen > 1; bufLen -= 2)
249: sum += *nBuf++;
250: if (bufLen == 1) {
251: *(u_char*)(&last) += *(u_char*) nBuf;
252: sum += last;
253: }
254:
255: sum = (sum >> 16) + (sum & 0xFFFF);
256: sum += sum >> 16;
257:
258: crc_Errno ^= crc_Errno;
259: return (u_short) ~sum;
260: }
261:
262: /*
263: * crcFletcher16() - Fletcher-16 Checksum computing
264: *
265: * @nBuf = Data for calculation
266: * @bufLen = Length of data
267: * return: -1 error, !=-1 Checksum
268: */
269: inline u_short
270: crcFletcher16(u_short * __restrict nBuf, int bufLen)
271: {
272: register u_short s1, s2;
273: register u_int clen;
274:
275: if (!nBuf) {
276: crc_SetErr(EINVAL, "Invalid parameters!");
277: return -1;
278: }
279:
280: s1 = s2 = 0xFF;
281: while (bufLen) {
282: clen = bufLen > MAX_FLETCHER16_DIGEST ? MAX_FLETCHER16_DIGEST : bufLen;
283: bufLen -= clen;
284:
285: do {
286: s1 += (u_short) *nBuf++;
287: s2 += s1;
288: } while (--clen);
289:
290: s1 = (s1 >> 8) + (s1 & 0xFF);
291: s2 = (s2 >> 8) + (s2 & 0xFF);
292: }
293:
294: crc_Errno ^= crc_Errno;
295: return (s2 << 8) | s1;
296: }
297:
298: /*
299: * crcFletcher() - Fletcher-32 Checksum computing
300: *
301: * @nBuf = Data for calculation
302: * @bufLen = Length of data
303: * return: -1 error, !=-1 Checksum
304: */
305: inline u_int
306: crcFletcher(u_short * __restrict nBuf, int bufLen)
307: {
308: register u_int s1, s2, clen;
309:
310: if (!nBuf) {
311: crc_SetErr(EINVAL, "Invalid parameters!");
312: return -1;
313: }
314:
315: s1 = s2 = 0xFFFF;
316: while (bufLen) {
317: clen = bufLen > MAX_FLETCHER_DIGEST ? MAX_FLETCHER_DIGEST : bufLen;
318: bufLen -= clen;
319:
320: do {
321: s1 += (u_int) *nBuf++;
322: s2 += s1;
323: } while (--clen);
324:
325: s1 = (s1 >> 16) + (s1 & 0xFFFF);
326: s2 = (s2 >> 16) + (s2 & 0xFFFF);
327: }
328:
329: crc_Errno ^= crc_Errno;
330: return (s2 << 16) | s1;
331: }
332:
333: /*
334: * crcAdler() - crcAdler-32 Checksum computing
335: *
336: * @psBuf = Data for calculation
337: * @bufLen = Length of data
338: * return: -1 error, !=-1 Checksum
339: */
340: inline u_int
341: crcAdler(u_char * __restrict psBuf, int bufLen)
342: {
343: register u_int s1, s2, clen;
344:
345: if (!psBuf) {
346: crc_SetErr(EINVAL, "Invalid parameters!");
347: return -1;
348: }
349:
350: s1 = 1L;
351: s2 ^= s2;
352: while (bufLen) {
353: clen = bufLen > MAX_ADLER_DIGEST ? MAX_ADLER_DIGEST : bufLen;
354: bufLen -= clen;
355:
356: do {
357: s1 += (u_int) *psBuf++;
358: s2 += s1;
359: } while (--clen);
360:
361: s1 %= crc_modAdler;
362: s2 %= crc_modAdler;
363: }
364:
365: crc_Errno ^= crc_Errno;
366: return (s2 << 16) | s1;
367: }
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