x86/crypto/crct10dif-pclmul_glue.c

0001 /*
0002  * Cryptographic API.
0003  *
0004  * T10 Data Integrity Field CRC16 Crypto Transform using PCLMULQDQ Instructions
0005  *
0006  * Copyright (C) 2013 Intel Corporation
0007  * Author: Tim Chen <tim.c.chen@linux.intel.com>
0008  *
0009  * This program is free software; you can redistribute it and/or modify it
0010  * under the terms of the GNU General Public License as published by the Free
0011  * Software Foundation; either version 2 of the License, or (at your option)
0012  * any later version.
0013  *
0014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
0015  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
0016  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
0017  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
0018  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
0019  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
0020  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
0021  * SOFTWARE.
0022  *
0023  */
0024
0025 #include <linux/types.h>
0026 #include <linux/module.h>
0027 #include <linux/crc-t10dif.h>
0028 #include <crypto/internal/hash.h>
0029 #include <crypto/internal/simd.h>
0030 #include <linux/init.h>
0031 #include <linux/string.h>
0032 #include <linux/kernel.h>
0033 #include <asm/cpufeatures.h>
0034 #include <asm/cpu_device_id.h>
0035 #include <asm/simd.h>
0036
0037 asmlinkage u16 crc_t10dif_pcl(u16 init_crc, const u8 *buf, size_t len);
0038
0039 struct chksum_desc_ctx {
0040     __u16 crc;
0041 };
0042
0043 static int chksum_init(struct shash_desc *desc)
0044 {
0045     struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
0046
0047     ctx->crc = 0;
0048
0049     return 0;
0050 }
0051
0052 static int chksum_update(struct shash_desc *desc, const u8 *data,
0053              unsigned int length)
0054 {
0055     struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
0056
0057     if (length >= 16 && crypto_simd_usable()) {
0058         kernel_fpu_begin();
0059         ctx->crc = crc_t10dif_pcl(ctx->crc, data, length);
0060         kernel_fpu_end();
0061     } else
0062         ctx->crc = crc_t10dif_generic(ctx->crc, data, length);
0063     return 0;
0064 }
0065
0066 static int chksum_final(struct shash_desc *desc, u8 *out)
0067 {
0068     struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
0069
0070     *(__u16 *)out = ctx->crc;
0071     return 0;
0072 }
0073
0074 static int __chksum_finup(__u16 crc, const u8 *data, unsigned int len, u8 *out)
0075 {
0076     if (len >= 16 && crypto_simd_usable()) {
0077         kernel_fpu_begin();
0078         *(__u16 *)out = crc_t10dif_pcl(crc, data, len);
0079         kernel_fpu_end();
0080     } else
0081         *(__u16 *)out = crc_t10dif_generic(crc, data, len);
0082     return 0;
0083 }
0084
0085 static int chksum_finup(struct shash_desc *desc, const u8 *data,
0086             unsigned int len, u8 *out)
0087 {
0088     struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
0089
0090     return __chksum_finup(ctx->crc, data, len, out);
0091 }
0092
0093 static int chksum_digest(struct shash_desc *desc, const u8 *data,
0094              unsigned int length, u8 *out)
0095 {
0096     return __chksum_finup(0, data, length, out);
0097 }
0098
0099 static struct shash_alg alg = {
0100     .digestsize     =   CRC_T10DIF_DIGEST_SIZE,
0101     .init       =   chksum_init,
0102     .update     =   chksum_update,
0103     .final      =   chksum_final,
0104     .finup      =   chksum_finup,
0105     .digest     =   chksum_digest,
0106     .descsize       =   sizeof(struct chksum_desc_ctx),
0107     .base           =   {
0108         .cra_name       =   "crct10dif",
0109         .cra_driver_name    =   "crct10dif-pclmul",
0110         .cra_priority       =   200,
0111         .cra_blocksize      =   CRC_T10DIF_BLOCK_SIZE,
0112         .cra_module     =   THIS_MODULE,
0113     }
0114 };
0115
0116 static const struct x86_cpu_id crct10dif_cpu_id[] = {
0117     X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL),
0118     {}
0119 };
0120 MODULE_DEVICE_TABLE(x86cpu, crct10dif_cpu_id);
0121
0122 static int __init crct10dif_intel_mod_init(void)
0123 {
0124     if (!x86_match_cpu(crct10dif_cpu_id))
0125         return -ENODEV;
0126
0127     return crypto_register_shash(&alg);
0128 }
0129
0130 static void __exit crct10dif_intel_mod_fini(void)
0131 {
0132     crypto_unregister_shash(&alg);
0133 }
0134
0135 module_init(crct10dif_intel_mod_init);
0136 module_exit(crct10dif_intel_mod_fini);
0137
0138 MODULE_AUTHOR("Tim Chen <tim.c.chen@linux.intel.com>");
0139 MODULE_DESCRIPTION("T10 DIF CRC calculation accelerated with PCLMULQDQ.");
0140 MODULE_LICENSE("GPL");
0141
0142 MODULE_ALIAS_CRYPTO("crct10dif");
0143 MODULE_ALIAS_CRYPTO("crct10dif-pclmul");