arch/x86/crypto/crct10dif-pclmul_glue.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * T10 Data Integrity Field CRC16 Crypto Transform using PCLMULQDQ Instructions
   5  *
   6  * Copyright (C) 2013 Intel Corporation
   7  * Author: Tim Chen <tim.c.chen@linux.intel.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the Free
  11  * Software Foundation; either version 2 of the License, or (at your option)
  12  * any later version.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  18  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  19  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  20  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  *
  23  */
  24
  25 #include <linux/types.h>
  26 #include <linux/module.h>
  27 #include <linux/crc-t10dif.h>
  28 #include <crypto/internal/hash.h>
  29 #include <crypto/internal/simd.h>
  30 #include <linux/init.h>
  31 #include <linux/string.h>
  32 #include <linux/kernel.h>
  33 #include <asm/cpufeatures.h>
  34 #include <asm/cpu_device_id.h>
  35 #include <asm/simd.h>
  36
  37 asmlinkage u16 crc_t10dif_pcl(u16 init_crc, const u8 *buf, size_t len);
  38
  39 struct chksum_desc_ctx {
  40         __u16 crc;
  41 };
  42
  43 static int chksum_init(struct shash_desc *desc)
  44 {
  45         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
  46
  47         ctx->crc = 0;
  48
  49         return 0;
  50 }
  51
  52 static int chksum_update(struct shash_desc *desc, const u8 *data,
  53                          unsigned int length)
  54 {
  55         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
  56
  57         if (length >= 16 && crypto_simd_usable()) {
  58                 kernel_fpu_begin();
  59                 ctx->crc = crc_t10dif_pcl(ctx->crc, data, length);
  60                 kernel_fpu_end();
  61         } else
  62                 ctx->crc = crc_t10dif_generic(ctx->crc, data, length);
  63         return 0;
  64 }
  65
  66 static int chksum_final(struct shash_desc *desc, u8 *out)
  67 {
  68         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
  69
  70         *(__u16 *)out = ctx->crc;
  71         return 0;
  72 }
  73
  74 static int __chksum_finup(__u16 crc, const u8 *data, unsigned int len, u8 *out)
  75 {
  76         if (len >= 16 && crypto_simd_usable()) {
  77                 kernel_fpu_begin();
  78                 *(__u16 *)out = crc_t10dif_pcl(crc, data, len);
  79                 kernel_fpu_end();
  80         } else
  81                 *(__u16 *)out = crc_t10dif_generic(crc, data, len);
  82         return 0;
  83 }
  84
  85 static int chksum_finup(struct shash_desc *desc, const u8 *data,
  86                         unsigned int len, u8 *out)
  87 {
  88         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
  89
  90         return __chksum_finup(ctx->crc, data, len, out);
  91 }
  92
  93 static int chksum_digest(struct shash_desc *desc, const u8 *data,
  94                          unsigned int length, u8 *out)
  95 {
  96         return __chksum_finup(0, data, length, out);
  97 }
  98
  99 static struct shash_alg alg = {
 100         .digestsize             =       CRC_T10DIF_DIGEST_SIZE,
 101         .init           =       chksum_init,
 102         .update         =       chksum_update,
 103         .final          =       chksum_final,
 104         .finup          =       chksum_finup,
 105         .digest         =       chksum_digest,
 106         .descsize               =       sizeof(struct chksum_desc_ctx),
 107         .base                   =       {
 108                 .cra_name               =       "crct10dif",
 109                 .cra_driver_name        =       "crct10dif-pclmul",
 110                 .cra_priority           =       200,
 111                 .cra_blocksize          =       CRC_T10DIF_BLOCK_SIZE,
 112                 .cra_module             =       THIS_MODULE,
 113         }
 114 };
 115
 116 static const struct x86_cpu_id crct10dif_cpu_id[] = {
 117         X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ),
 118         {}
 119 };
 120 MODULE_DEVICE_TABLE(x86cpu, crct10dif_cpu_id);
 121
 122 static int __init crct10dif_intel_mod_init(void)
 123 {
 124         if (!x86_match_cpu(crct10dif_cpu_id))
 125                 return -ENODEV;
 126
 127         return crypto_register_shash(&alg);
 128 }
 129
 130 static void __exit crct10dif_intel_mod_fini(void)
 131 {
 132         crypto_unregister_shash(&alg);
 133 }
 134
 135 module_init(crct10dif_intel_mod_init);
 136 module_exit(crct10dif_intel_mod_fini);
 137
 138 MODULE_AUTHOR("Tim Chen <tim.c.chen@linux.intel.com>");
 139 MODULE_DESCRIPTION("T10 DIF CRC calculation accelerated with PCLMULQDQ.");
 140 MODULE_LICENSE("GPL");
 141
 142 MODULE_ALIAS_CRYPTO("crct10dif");
 143 MODULE_ALIAS_CRYPTO("crct10dif-pclmul");