arch/x86/crypto/sha256_ssse3_glue.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * Glue code for the SHA256 Secure Hash Algorithm assembler
   5  * implementation using supplemental SSE3 / AVX / AVX2 instructions.
   6  *
   7  * This file is based on sha256_generic.c
   8  *
   9  * Copyright (C) 2013 Intel Corporation.
  10  *
  11  * Author:
  12  *     Tim Chen <tim.c.chen@linux.intel.com>
  13  *
  14  * This program is free software; you can redistribute it and/or modify it
  15  * under the terms of the GNU General Public License as published by the Free
  16  * Software Foundation; either version 2 of the License, or (at your option)
  17  * any later version.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  20  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  22  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  23  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  24  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  25  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  26  * SOFTWARE.
  27  */
  28
  29
  30 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  31
  32 #include <crypto/internal/hash.h>
  33 #include <linux/init.h>
  34 #include <linux/module.h>
  35 #include <linux/mm.h>
  36 #include <linux/cryptohash.h>
  37 #include <linux/types.h>
  38 #include <crypto/sha.h>
  39 #include <crypto/sha256_base.h>
  40 #include <asm/fpu/api.h>
  41 #include <linux/string.h>
  42
  43 asmlinkage void sha256_transform_ssse3(u32 *digest, const char *data,
  44                                        u64 rounds);
  45 #ifdef CONFIG_AS_AVX
  46 asmlinkage void sha256_transform_avx(u32 *digest, const char *data,
  47                                      u64 rounds);
  48 #endif
  49 #ifdef CONFIG_AS_AVX2
  50 asmlinkage void sha256_transform_rorx(u32 *digest, const char *data,
  51                                       u64 rounds);
  52 #endif
  53
  54 static void (*sha256_transform_asm)(u32 *, const char *, u64);
  55
  56 static int sha256_ssse3_update(struct shash_desc *desc, const u8 *data,
  57                              unsigned int len)
  58 {
  59         struct sha256_state *sctx = shash_desc_ctx(desc);
  60
  61         if (!irq_fpu_usable() ||
  62             (sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
  63                 return crypto_sha256_update(desc, data, len);
  64
  65         /* make sure casting to sha256_block_fn() is safe */
  66         BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0);
  67
  68         kernel_fpu_begin();
  69         sha256_base_do_update(desc, data, len,
  70                               (sha256_block_fn *)sha256_transform_asm);
  71         kernel_fpu_end();
  72
  73         return 0;
  74 }
  75
  76 static int sha256_ssse3_finup(struct shash_desc *desc, const u8 *data,
  77                               unsigned int len, u8 *out)
  78 {
  79         if (!irq_fpu_usable())
  80                 return crypto_sha256_finup(desc, data, len, out);
  81
  82         kernel_fpu_begin();
  83         if (len)
  84                 sha256_base_do_update(desc, data, len,
  85                                       (sha256_block_fn *)sha256_transform_asm);
  86         sha256_base_do_finalize(desc, (sha256_block_fn *)sha256_transform_asm);
  87         kernel_fpu_end();
  88
  89         return sha256_base_finish(desc, out);
  90 }
  91
  92 /* Add padding and return the message digest. */
  93 static int sha256_ssse3_final(struct shash_desc *desc, u8 *out)
  94 {
  95         return sha256_ssse3_finup(desc, NULL, 0, out);
  96 }
  97
  98 static struct shash_alg algs[] = { {
  99         .digestsize     =       SHA256_DIGEST_SIZE,
 100         .init           =       sha256_base_init,
 101         .update         =       sha256_ssse3_update,
 102         .final          =       sha256_ssse3_final,
 103         .finup          =       sha256_ssse3_finup,
 104         .descsize       =       sizeof(struct sha256_state),
 105         .base           =       {
 106                 .cra_name       =       "sha256",
 107                 .cra_driver_name =      "sha256-ssse3",
 108                 .cra_priority   =       150,
 109                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 110                 .cra_blocksize  =       SHA256_BLOCK_SIZE,
 111                 .cra_module     =       THIS_MODULE,
 112         }
 113 }, {
 114         .digestsize     =       SHA224_DIGEST_SIZE,
 115         .init           =       sha224_base_init,
 116         .update         =       sha256_ssse3_update,
 117         .final          =       sha256_ssse3_final,
 118         .finup          =       sha256_ssse3_finup,
 119         .descsize       =       sizeof(struct sha256_state),
 120         .base           =       {
 121                 .cra_name       =       "sha224",
 122                 .cra_driver_name =      "sha224-ssse3",
 123                 .cra_priority   =       150,
 124                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 125                 .cra_blocksize  =       SHA224_BLOCK_SIZE,
 126                 .cra_module     =       THIS_MODULE,
 127         }
 128 } };
 129
 130 #ifdef CONFIG_AS_AVX
 131 static bool __init avx_usable(void)
 132 {
 133         if (!cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, NULL)) {
 134                 if (cpu_has_avx)
 135                         pr_info("AVX detected but unusable.\n");
 136                 return false;
 137         }
 138
 139         return true;
 140 }
 141 #endif
 142
 143 static int __init sha256_ssse3_mod_init(void)
 144 {
 145         /* test for SSSE3 first */
 146         if (cpu_has_ssse3)
 147                 sha256_transform_asm = sha256_transform_ssse3;
 148
 149 #ifdef CONFIG_AS_AVX
 150         /* allow AVX to override SSSE3, it's a little faster */
 151         if (avx_usable()) {
 152 #ifdef CONFIG_AS_AVX2
 153                 if (boot_cpu_has(X86_FEATURE_AVX2) && boot_cpu_has(X86_FEATURE_BMI2))
 154                         sha256_transform_asm = sha256_transform_rorx;
 155                 else
 156 #endif
 157                         sha256_transform_asm = sha256_transform_avx;
 158         }
 159 #endif
 160
 161         if (sha256_transform_asm) {
 162 #ifdef CONFIG_AS_AVX
 163                 if (sha256_transform_asm == sha256_transform_avx)
 164                         pr_info("Using AVX optimized SHA-256 implementation\n");
 165 #ifdef CONFIG_AS_AVX2
 166                 else if (sha256_transform_asm == sha256_transform_rorx)
 167                         pr_info("Using AVX2 optimized SHA-256 implementation\n");
 168 #endif
 169                 else
 170 #endif
 171                         pr_info("Using SSSE3 optimized SHA-256 implementation\n");
 172                 return crypto_register_shashes(algs, ARRAY_SIZE(algs));
 173         }
 174         pr_info("Neither AVX nor SSSE3 is available/usable.\n");
 175
 176         return -ENODEV;
 177 }
 178
 179 static void __exit sha256_ssse3_mod_fini(void)
 180 {
 181         crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
 182 }
 183
 184 module_init(sha256_ssse3_mod_init);
 185 module_exit(sha256_ssse3_mod_fini);
 186
 187 MODULE_LICENSE("GPL");
 188 MODULE_DESCRIPTION("SHA256 Secure Hash Algorithm, Supplemental SSE3 accelerated");
 189
 190 MODULE_ALIAS_CRYPTO("sha256");
 191 MODULE_ALIAS_CRYPTO("sha224");