/*
* 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 at 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 *crcp, const u8 *data, unsigned int len,
u8 *out)
{
*(__u16 *)out = crc_t10dif_generic(*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_desc_ctx *ctx = shash_desc_ctx(desc);
return __chksum_finup(&ctx->crc, 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)
{
int ret;
ret = crypto_register_shash(&alg);
return ret;
}
static void __exit crct10dif_mod_fini(void)
{
crypto_unregister_shash(&alg);
}
module_init(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("crct10dif");
