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 2011/04/28 20:28:20 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
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: //
76: // Error maintenance functions ...
77: //
78:
79: // crc_GetErrno() Get error code of last operation
80: inline int crc_GetErrno()
81: {
82: return crc_Errno;
83: }
84:
85: // crc_GetError() Get error text of last operation
86: inline const char *crc_GetError()
87: {
88: return crc_Error;
89: }
90:
91: // crcSetErr() Set error to variables for internal use!!!
92: inline void crcSetErr(int eno, char *estr, ...)
93: {
94: va_list lst;
95:
96: crc_Errno = eno;
97: memset(crc_Error, 0, MAX_STR + 1);
98: va_start(lst, estr);
99: vsnprintf(crc_Error, MAX_STR + 1, estr, lst);
100: va_end(lst);
101: }
102:
103: // ----------------------------------------------------------
104:
105: /*
106: * crcReflect() Reflect all bits of number
107: * @crcNum = Number for reflection
108: * @crcBits = Number width bits
109: * return: -1 error, !=-1 reflecting number
110: */
111: inline u_int
112: crcReflect(u_int crcNum, u_char crcBits)
113: {
114: register u_int i, j, rev;
115:
116: for (i = (u_int) 1 << (crcBits - 1), j = 1, rev ^= rev; i; i >>= 1, j <<= 1)
117: if (crcNum & i)
118: rev |= j;
119:
120: crc_Errno ^= crc_Errno;
121: return rev;
122: }
123:
124: /*
125: * crcCalc() Generic CRC calculation function for many sub variants of CRC algorithms
126: * @psBuf = Data for calculation
127: * @bufLen = Length of data
128: * @crcBits = CRC algorithm bits (1, 4, 5, 6, 7, 8, 10, 11, 12, 15, 16, 24, 30, 32)
129: * @RevOpts = Options for computation (REVOPTS_REVERTBYTE, REVOPTS_REVERTCRC)
130: * @initCRC = Initial CRC value
131: * @xorCRC = Last xor CRC value
132: * return: -1 error, !=-1 CRC checksum
133: */
134: inline u_int
135: crcCalc(u_char * __restrict psBuf, u_int bufLen, u_char crcBits, u_char RevOpts, u_int initCRC, u_int xorCRC)
136: {
137: const u_int bits = sizeof(int) * 8 - crcBits;
138: u_int poly, crchibit, crc;
139: register u_int i, j, b, ch;
140:
141: if (!psBuf) {
142: crc_Errno = 1;
143: strlcpy(crc_Error, "crcCalc(): Invalid parameters!", MAX_STR + 1);
144: return -1;
145: }
146:
147: switch (crcBits) {
148: case 1:
149: poly = crc_Poly[0].poly_num;
150: break;
151: case 4:
152: poly = crc_Poly[1].poly_num;
153: break;
154: case 5:
155: poly = crc_Poly[2].poly_num;
156: break;
157: case 6:
158: poly = crc_Poly[3].poly_num;
159: break;
160: case 7:
161: poly = crc_Poly[4].poly_num;
162: break;
163: case 8:
164: poly = crc_Poly[5].poly_num;
165: break;
166: case 10:
167: poly = crc_Poly[6].poly_num;
168: break;
169: case 11:
170: poly = crc_Poly[7].poly_num;
171: break;
172: case 12:
173: poly = crc_Poly[8].poly_num;
174: break;
175: case 15:
176: poly = crc_Poly[9].poly_num;
177: break;
178: case 16:
179: poly = crc_Poly[10].poly_num;
180: break;
181: case 24:
182: poly = crc_Poly[11].poly_num;
183: break;
184: case 30:
185: poly = crc_Poly[12].poly_num;
186: break;
187: case 32:
188: poly = crc_Poly[13].poly_num;
189: break;
190: default:
191: crc_Errno = 2;
192: strlcpy(crc_Error, "crcCalc(): Unsupported CRC method!!!", MAX_STR + 1);
193: return -1;
194: }
195: poly <<= bits;
196:
197: crchibit = (u_int) 1 << (crcBits - 1);
198: crchibit <<= bits;
199: crc = initCRC << bits;
200:
201: for (i = 0; i < bufLen; i++) {
202: ch = (u_int) *psBuf++;
203: if (RevOpts & REVOPTS_REVERTBYTE)
204: ch = crcReflect(ch, 8);
205:
206: for (j = 0x80; j; j >>= 1) {
207: b = crc & crchibit;
208: crc <<= 1;
209:
210: if (ch & j)
211: b ^= crchibit;
212: if (b)
213: crc ^= poly;
214: }
215: }
216:
217: if (RevOpts & REVOPTS_REVERTCRC)
218: crc = crcReflect(crc, sizeof(int) * 8);
219: crc ^= xorCRC << bits;
220: crc &= (((crchibit - 1) << 1) | 1);
221: if (!(RevOpts & REVOPTS_REVERTCRC))
222: crc >>= bits;
223:
224: crc_Errno ^= crc_Errno;
225: return crc;
226: }
227:
228: // ----------------------------------------------------------
229:
230: /*
231: * crcIP() Checksum in IP communication
232: * @nBuf = Data for calculation
233: * @bufLen = Length of data
234: * return: -1 error, !=-1 Checksum
235: */
236: inline u_short
237: crcIP(u_short * __restrict nBuf, int bufLen)
238: {
239: register u_int sum;
240:
241: if (!nBuf) {
242: crc_Errno = 1;
243: strlcpy(crc_Error, "crcIP(): Invalid parameters!", MAX_STR + 1);
244: return -1;
245: }
246:
247: for (sum = 0; bufLen; bufLen--)
248: sum += *nBuf++;
249:
250: sum = (sum >> 16) + (sum & 0xFFFF);
251: sum += sum >> 16;
252:
253: crc_Errno ^= crc_Errno;
254: return (u_short) ~sum;
255: }
256:
257: /*
258: * crcFletcher16() Fletcher-16 Checksum computing
259: * @nBuf = Data for calculation
260: * @bufLen = Length of data
261: * return: -1 error, !=-1 Checksum
262: */
263: inline u_short
264: crcFletcher16(u_short * __restrict nBuf, int bufLen)
265: {
266: register u_short s1, s2;
267: register u_int clen;
268:
269: if (!nBuf) {
270: crc_Errno = 1;
271: strlcpy(crc_Error, "crcFletcher16(): Invalid parameters!", MAX_STR + 1);
272: return -1;
273: }
274:
275: s1 = s2 = 0xFF;
276: while (bufLen) {
277: clen = bufLen > MAX_FLETCHER16_DIGEST ? MAX_FLETCHER16_DIGEST : bufLen;
278: bufLen -= clen;
279:
280: do {
281: s1 += (u_short) *nBuf++;
282: s2 += s1;
283: } while (--clen);
284:
285: s1 = (s1 >> 8) + (s1 & 0xFF);
286: s2 = (s2 >> 8) + (s2 & 0xFF);
287: }
288:
289: crc_Errno ^= crc_Errno;
290: return (s2 << 8) | s1;
291: }
292:
293: /*
294: * crcFletcher() Fletcher-32 Checksum computing
295: * @nBuf = Data for calculation
296: * @bufLen = Length of data
297: * return: -1 error, !=-1 Checksum
298: */
299: inline u_int
300: crcFletcher(u_short * __restrict nBuf, int bufLen)
301: {
302: register u_int s1, s2, clen;
303:
304: if (!nBuf) {
305: crc_Errno = 1;
306: strlcpy(crc_Error, "crcFletcher(): Invalid parameters!", MAX_STR + 1);
307: return -1;
308: }
309:
310: s1 = s2 = 0xFFFF;
311: while (bufLen) {
312: clen = bufLen > MAX_FLETCHER_DIGEST ? MAX_FLETCHER_DIGEST : bufLen;
313: bufLen -= clen;
314:
315: do {
316: s1 += (u_int) *nBuf++;
317: s2 += s1;
318: } while (--clen);
319:
320: s1 = (s1 >> 16) + (s1 & 0xFFFF);
321: s2 = (s2 >> 16) + (s2 & 0xFFFF);
322: }
323:
324: crc_Errno ^= crc_Errno;
325: return (s2 << 16) | s1;
326: }
327:
328: /*
329: * crcAdler() crcAdler-32 Checksum computing
330: * @psBuf = Data for calculation
331: * @bufLen = Length of data
332: * return: -1 error, !=-1 Checksum
333: */
334: inline u_int
335: crcAdler(u_char * __restrict psBuf, int bufLen)
336: {
337: register u_int s1, s2, clen;
338:
339: if (!psBuf) {
340: crc_Errno = 1;
341: strlcpy(crc_Error, "crcAdler(): Invalid parameters!", MAX_STR + 1);
342: return -1;
343: }
344:
345: s1 = 1L;
346: s2 ^= s2;
347: while (bufLen) {
348: clen = bufLen > MAX_ADLER_DIGEST ? MAX_ADLER_DIGEST : bufLen;
349: bufLen -= clen;
350:
351: do {
352: s1 += (u_int) *psBuf++;
353: s2 += s1;
354: } while (--clen);
355:
356: s1 %= crc_modAdler;
357: s2 %= crc_modAdler;
358: }
359:
360: crc_Errno ^= crc_Errno;
361: return (s2 << 16) | s1;
362: }
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