diff options
Diffstat (limited to 'crypto/crc32c.c')
| -rw-r--r-- | crypto/crc32c.c | 172 |
1 files changed, 0 insertions, 172 deletions
diff --git a/crypto/crc32c.c b/crypto/crc32c.c deleted file mode 100644 index 06f7018c9d95..000000000000 --- a/crypto/crc32c.c +++ /dev/null @@ -1,172 +0,0 @@ -/* - * Cryptographic API. - * - * CRC32C chksum - * - *@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!) - * <endoflist> - * - * Copyright (c) 2004 Cisco Systems, Inc. - * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au> - * - * 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 <crypto/internal/hash.h> -#include <linux/init.h> -#include <linux/module.h> -#include <linux/string.h> -#include <linux/kernel.h> -#include <linux/crc32.h> - -#define CHKSUM_BLOCK_SIZE 1 -#define CHKSUM_DIGEST_SIZE 4 - -struct chksum_ctx { - u32 key; -}; - -struct chksum_desc_ctx { - u32 crc; -}; - -/* - * Steps through buffer one byte at at time, calculates reflected - * crc using table. - */ - -static int chksum_init(struct shash_desc *desc) -{ - struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); - struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - - ctx->crc = mctx->key; - - return 0; -} - -/* - * Setting the seed allows arbitrary accumulators and flexible XOR policy - * If your algorithm starts with ~0, then XOR with ~0 before you set - * the seed. - */ -static int chksum_setkey(struct crypto_shash *tfm, const u8 *key, - unsigned int keylen) -{ - struct chksum_ctx *mctx = crypto_shash_ctx(tfm); - - if (keylen != sizeof(mctx->key)) { - crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); - return -EINVAL; - } - mctx->key = le32_to_cpu(*(__le32 *)key); - return 0; -} - -static int chksum_update(struct shash_desc *desc, const u8 *data, - unsigned int length) -{ - struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - - ctx->crc = __crc32c_le(ctx->crc, data, length); - return 0; -} - -static int chksum_final(struct shash_desc *desc, u8 *out) -{ - struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - - *(__le32 *)out = ~cpu_to_le32p(&ctx->crc); - return 0; -} - -static int __chksum_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *out) -{ - *(__le32 *)out = ~cpu_to_le32(__crc32c_le(*crcp, data, len)); - return 0; -} - -static int chksum_finup(struct shash_desc *desc, const u8 *data, - unsigned int len, u8 *out) -{ - struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - - return __chksum_finup(&ctx->crc, data, len, out); -} - -static int chksum_digest(struct shash_desc *desc, const u8 *data, - unsigned int length, u8 *out) -{ - struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); - - return __chksum_finup(&mctx->key, data, length, out); -} - -static int crc32c_cra_init(struct crypto_tfm *tfm) -{ - struct chksum_ctx *mctx = crypto_tfm_ctx(tfm); - - mctx->key = ~0; - return 0; -} - -static struct shash_alg alg = { - .digestsize = CHKSUM_DIGEST_SIZE, - .setkey = chksum_setkey, - .init = chksum_init, - .update = chksum_update, - .final = chksum_final, - .finup = chksum_finup, - .digest = chksum_digest, - .descsize = sizeof(struct chksum_desc_ctx), - .base = { - .cra_name = "crc32c", - .cra_driver_name = "crc32c-generic", - .cra_priority = 100, - .cra_blocksize = CHKSUM_BLOCK_SIZE, - .cra_alignmask = 3, - .cra_ctxsize = sizeof(struct chksum_ctx), - .cra_module = THIS_MODULE, - .cra_init = crc32c_cra_init, - } -}; - -static int __init crc32c_mod_init(void) -{ - return crypto_register_shash(&alg); -} - -static void __exit crc32c_mod_fini(void) -{ - crypto_unregister_shash(&alg); -} - -module_init(crc32c_mod_init); -module_exit(crc32c_mod_fini); - -MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>"); -MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations wrapper for lib/crc32c"); -MODULE_LICENSE("GPL"); |