From 871480933a1c28f8a9fed4c4d34d06c439a7a422 Mon Sep 17 00:00:00 2001 From: Srikant Patnaik Date: Sun, 11 Jan 2015 12:28:04 +0530 Subject: Moved, renamed, and deleted files The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure. --- lib/libcrc32c.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 lib/libcrc32c.c (limited to 'lib/libcrc32c.c') diff --git a/lib/libcrc32c.c b/lib/libcrc32c.c new file mode 100644 index 00000000..244f5480 --- /dev/null +++ b/lib/libcrc32c.c @@ -0,0 +1,81 @@ +/* + * CRC32C + *@Article{castagnoli-crc, + * author = { Guy Castagnoli and Stefan Braeuer and Martin Herrman}, + * title = {{Optimization of Cyclic Redundancy-Check Codes with 24 + * and 32 Parity Bits}}, + * journal = IEEE Transactions on Communication, + * year = {1993}, + * volume = {41}, + * number = {6}, + * pages = {}, + * month = {June}, + *} + * Used by the iSCSI driver, possibly others, and derived from the + * the iscsi-crc.c module of the linux-iscsi driver at + * http://linux-iscsi.sourceforge.net. + * + * Following the example of lib/crc32, this function is intended to be + * flexible and useful for all users. Modules that currently have their + * own crc32c, but hopefully may be able to use this one are: + * net/sctp (please add all your doco to here if you change to + * use this one!) + * + * + * Copyright (c) 2004 Cisco Systems, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include +#include +#include +#include +#include + +static struct crypto_shash *tfm; + +u32 crc32c(u32 crc, const void *address, unsigned int length) +{ + struct { + struct shash_desc shash; + char ctx[crypto_shash_descsize(tfm)]; + } desc; + int err; + + desc.shash.tfm = tfm; + desc.shash.flags = 0; + *(u32 *)desc.ctx = crc; + + err = crypto_shash_update(&desc.shash, address, length); + BUG_ON(err); + + return *(u32 *)desc.ctx; +} + +EXPORT_SYMBOL(crc32c); + +static int __init libcrc32c_mod_init(void) +{ + tfm = crypto_alloc_shash("crc32c", 0, 0); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + return 0; +} + +static void __exit libcrc32c_mod_fini(void) +{ + crypto_free_shash(tfm); +} + +module_init(libcrc32c_mod_init); +module_exit(libcrc32c_mod_fini); + +MODULE_AUTHOR("Clay Haapala "); +MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations"); +MODULE_LICENSE("GPL"); -- cgit