/* * Cryptographic API. * * T10 Data Integrity Field CRC16 Crypto Transform * * Copyright (c) 2007 Oracle Corporation. All rights reserved. * Written by Martin K. Petersen <martin.petersen@oracle.com> * Copyright (C) 2013 Intel Corporation * Author: Tim Chen <tim.c.chen@linux.intel.com> * * 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. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * */ #include <linux/module.h> #include <linux/crc-t10dif.h> #include <crypto/internal/hash.h> #include <linux/init.h> #include <linux/kernel.h> struct chksum_desc_ctx { __u16 crc; }; /* * Steps through buffer one byte at a time, calculates reflected * crc using table. */ static int chksum_init(struct shash_desc *desc) { struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); ctx->crc = 0; 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 = crc_t10dif_generic(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); *(__u16 *)out = ctx->crc; return 0; } static int __chksum_finup(__u16 crc, const u8 *data, unsigned int len, u8 *out) { *(__u16 *)out = crc_t10dif_generic(crc, 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) { return __chksum_finup(0, data, length, out); } static struct shash_alg alg = { .digestsize = CRC_T10DIF_DIGEST_SIZE, .init = chksum_init, .update = chksum_update, .final = chksum_final, .finup = chksum_finup, .digest = chksum_digest, .descsize = sizeof(struct chksum_desc_ctx), .base = { .cra_name = "crct10dif", .cra_driver_name = "crct10dif-generic", .cra_priority = 100, .cra_blocksize = CRC_T10DIF_BLOCK_SIZE, .cra_module = THIS_MODULE, } }; static int __init crct10dif_mod_init(void) { return crypto_register_shash(&alg); } static void __exit crct10dif_mod_fini(void) { crypto_unregister_shash(&alg); } subsys_initcall(crct10dif_mod_init); module_exit(crct10dif_mod_fini); MODULE_AUTHOR("Tim Chen <tim.c.chen@linux.intel.com>"); MODULE_DESCRIPTION("T10 DIF CRC calculation."); MODULE_LICENSE("GPL"); MODULE_ALIAS_CRYPTO("crct10dif"); MODULE_ALIAS_CRYPTO("crct10dif-generic");