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AgeCommit message (Expand)Author
2015-08-16Move FAQ to the web.Rich Salz
2015-08-13Fix FAQ formatting for new website.Rich Salz
2015-05-05Update multi-thread FAQRich Salz
2014-12-03New location on website for binaries.Rich Salz
2014-08-19PR2401: Typos in FAQJeffrey Walton
2014-07-03Close 3170, remove reference to Ariel Glenn's old 0.9.8 docRich Salz
2014-04-25Remove latest version, it's pretty redundant and just one more thingMark J. Cox
2014-04-04Update FAQ.Dr. Stephen Henson
2014-01-08update FAQDr. Stephen Henson
2013-12-28FAQ: why SIGILL?Andy Polyakov
2013-11-11Update FAQDr. Stephen Henson
2013-11-10Update FAQ with PGP note.Dr. Stephen Henson
2013-10-20Remove gratuitous patent referencesSteve Marquess
2013-09-08Remove ancient PATENTS section and FAQ reference.Dr. Stephen Henson
2013-09-05misspellings fixes by https://github.com/vlajos/misspell_fixerVeres Lajos
2013-08-14Add the server 'hang' issue to the FAQDr. Stephen Henson
2013-02-12Upate FAQ.Dr. Stephen Henson
2013-02-11update FAQDr. Stephen Henson
2013-02-11FAQ/README: we are now using Git instead of CVSLutz Jaenicke
2012-05-10update FAQDr. Stephen Henson
2012-04-26update FAQDr. Stephen Henson
2012-04-22correct old FAQ answersDr. Stephen Henson
2012-04-19update FAQDr. Stephen Henson
2012-04-05add FAQ about version numbersDr. Stephen Henson
2012-03-14update FAQ, NEWSDr. Stephen Henson
2012-01-04update FAQDr. Stephen Henson
2011-09-06Update FAQ.Dr. Stephen Henson
2011-02-08OCSP stapling fix (OpenSSL 0.9.8r/1.0.0d)Bodo Möller
2010-12-02update FAQDr. Stephen Henson
2010-12-02use right version this time in FAQDr. Stephen Henson
2010-12-02update FAQDr. Stephen Henson
2010-10-04Typo, PR#2346Dr. Stephen Henson
2010-06-01update FAQDr. Stephen Henson
2010-04-14update FAQDr. Stephen Henson
2010-03-31fix FAQ (again)Dr. Stephen Henson
2010-03-30update FAQDr. Stephen Henson
2010-03-30fix FAQDr. Stephen Henson
2010-03-30update FAQDr. Stephen Henson
2010-03-30update FAQDr. Stephen Henson
2010-03-30update HEAD FAQDr. Stephen Henson
2010-03-25update FAQDr. Stephen Henson
2010-02-26oops, use correct dateDr. Stephen Henson
2010-02-25update FAQDr. Stephen Henson
2009-10-23ClarificationDr. Stephen Henson
2009-10-23Add an FAQ.Dr. Stephen Henson
2009-06-24Update FAQ with note about online docs.Dr. Stephen Henson
2009-03-25Update FAQ.Dr. Stephen Henson
2009-01-07Update FAQ.Dr. Stephen Henson
2008-09-15Update FAQ.Dr. Stephen Henson
2008-08-06Correct the FAQ and the threads man page re: CRYPTO_THREADID changes.Geoff Thorpe
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/*
 * Aug 8, 2011 Bob Pearson with help from Joakim Tjernlund and George Spelvin
 * cleaned up code to current version of sparse and added the slicing-by-8
 * algorithm to the closely similar existing slicing-by-4 algorithm.
 *
 * Oct 15, 2000 Matt Domsch <Matt_Domsch@dell.com>
 * Nicer crc32 functions/docs submitted by linux@horizon.com.  Thanks!
 * Code was from the public domain, copyright abandoned.  Code was
 * subsequently included in the kernel, thus was re-licensed under the
 * GNU GPL v2.
 *
 * Oct 12, 2000 Matt Domsch <Matt_Domsch@dell.com>
 * Same crc32 function was used in 5 other places in the kernel.
 * I made one version, and deleted the others.
 * There are various incantations of crc32().  Some use a seed of 0 or ~0.
 * Some xor at the end with ~0.  The generic crc32() function takes
 * seed as an argument, and doesn't xor at the end.  Then individual
 * users can do whatever they need.
 *   drivers/net/smc9194.c uses seed ~0, doesn't xor with ~0.
 *   fs/jffs2 uses seed 0, doesn't xor with ~0.
 *   fs/partitions/efi.c uses seed ~0, xor's with ~0.
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2.  See the file COPYING for more details.
 */

/* see: Documentation/crc32.txt for a description of algorithms */

#include <linux/crc32.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/sched.h>
#include "crc32defs.h"

#if CRC_LE_BITS > 8
# define tole(x) ((__force u32) cpu_to_le32(x))
#else
# define tole(x) (x)
#endif

#if CRC_BE_BITS > 8
# define tobe(x) ((__force u32) cpu_to_be32(x))
#else
# define tobe(x) (x)
#endif

#include "crc32table.h"

MODULE_AUTHOR("Matt Domsch <Matt_Domsch@dell.com>");
MODULE_DESCRIPTION("Various CRC32 calculations");
MODULE_LICENSE("GPL");

#if CRC_LE_BITS > 8 || CRC_BE_BITS > 8

/* implements slicing-by-4 or slicing-by-8 algorithm */
static inline u32 __pure
crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 (*tab)[256])
{
# ifdef __LITTLE_ENDIAN
#  define DO_CRC(x) crc = t0[(crc ^ (x)) & 255] ^ (crc >> 8)
#  define DO_CRC4 (t3[(q) & 255] ^ t2[(q >> 8) & 255] ^ \
		   t1[(q >> 16) & 255] ^ t0[(q >> 24) & 255])
#  define DO_CRC8 (t7[(q) & 255] ^ t6[(q >> 8) & 255] ^ \
		   t5[(q >> 16) & 255] ^ t4[(q >> 24) & 255])
# else
#  define DO_CRC(x) crc = t0[((crc >> 24) ^ (x)) & 255] ^ (crc << 8)
#  define DO_CRC4 (t0[(q) & 255] ^ t1[(q >> 8) & 255] ^ \
		   t2[(q >> 16) & 255] ^ t3[(q >> 24) & 255])
#  define DO_CRC8 (t4[(q) & 255] ^ t5[(q >> 8) & 255] ^ \
		   t6[(q >> 16) & 255] ^ t7[(q >> 24) & 255])
# endif
	const u32 *b;
	size_t    rem_len;
# ifdef CONFIG_X86
	size_t i;
# endif
	const u32 *t0=tab[0], *t1=tab[1], *t2=tab[2], *t3=tab[3];
# if CRC_LE_BITS != 32
	const u32 *t4 = tab[4], *t5 = tab[5], *t6 = tab[6], *t7 = tab[7];
# endif
	u32 q;

	/* Align it */
	if (unlikely((long)buf & 3 && len)) {
		do {
			DO_CRC(*buf++);
		} while ((--len) && ((long)buf)&3);
	}

# if CRC_LE_BITS == 32
	rem_len = len & 3;
	len = len >> 2;
# else
	rem_len = len & 7;
	len = len >> 3;
# endif

	b = (const u32 *)buf;
# ifdef CONFIG_X86
	--b;
	for (i = 0; i < len; i++) {
# else
	for (--b; len; --len) {
# endif
		q = crc ^ *++b; /* use pre increment for speed */
# if CRC_LE_BITS == 32
		crc = DO_CRC4;
# else
		crc = DO_CRC8;
		q = *++b;
		crc ^= DO_CRC4;
# endif
	}
	len = rem_len;
	/* And the last few bytes */
	if (len) {
		u8 *p = (u8 *)(b + 1) - 1;
# ifdef CONFIG_X86
		for (i = 0; i < len; i++)
			DO_CRC(*++p); /* use pre increment for speed */
# else
		do {
			DO_CRC(*++p); /* use pre increment for speed */
		} while (--len);
# endif
	}
	return crc;
#undef DO_CRC
#undef DO_CRC4
#undef DO_CRC8
}
#endif


/**
 * crc32_le_generic() - Calculate bitwise little-endian Ethernet AUTODIN II
 *			CRC32/CRC32C
 * @crc: seed value for computation.  ~0 for Ethernet, s