arch/x86/crypto/sha1_ssse3_glue.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * Glue code for the SHA1 Secure Hash Algorithm assembler implementation using
   5  * Supplemental SSE3 instructions.
   6  *
   7  * This file is based on sha1_generic.c
   8  *
   9  * Copyright (c) Alan Smithee.
  10  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
  11  * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
  12  * Copyright (c) Mathias Krause <minipli@googlemail.com>
  13  * Copyright (c) Chandramouli Narayanan <mouli@linux.intel.com>
  14  *
  15  * This program is free software; you can redistribute it and/or modify it
  16  * under the terms of the GNU General Public License as published by the Free
  17  * Software Foundation; either version 2 of the License, or (at your option)
  18  * any later version.
  19  *
  20  */
  21
  22 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  23
  24 #include <crypto/internal/hash.h>
  25 #include <linux/init.h>
  26 #include <linux/module.h>
  27 #include <linux/mm.h>
  28 #include <linux/cryptohash.h>
  29 #include <linux/types.h>
  30 #include <crypto/sha.h>
  31 #include <crypto/sha1_base.h>
  32 #include <asm/fpu/api.h>
  33
  34
  35 asmlinkage void sha1_transform_ssse3(u32 *digest, const char *data,
  36                                      unsigned int rounds);
  37 #ifdef CONFIG_AS_AVX
  38 asmlinkage void sha1_transform_avx(u32 *digest, const char *data,
  39                                    unsigned int rounds);
  40 #endif
  41 #ifdef CONFIG_AS_AVX2
  42 #define SHA1_AVX2_BLOCK_OPTSIZE 4       /* optimal 4*64 bytes of SHA1 blocks */
  43
  44 asmlinkage void sha1_transform_avx2(u32 *digest, const char *data,
  45                                     unsigned int rounds);
  46 #endif
  47
  48 static void (*sha1_transform_asm)(u32 *, const char *, unsigned int);
  49
  50 static int sha1_ssse3_update(struct shash_desc *desc, const u8 *data,
  51                              unsigned int len)
  52 {
  53         struct sha1_state *sctx = shash_desc_ctx(desc);
  54
  55         if (!irq_fpu_usable() ||
  56             (sctx->count % SHA1_BLOCK_SIZE) + len < SHA1_BLOCK_SIZE)
  57                 return crypto_sha1_update(desc, data, len);
  58
  59         /* make sure casting to sha1_block_fn() is safe */
  60         BUILD_BUG_ON(offsetof(struct sha1_state, state) != 0);
  61
  62         kernel_fpu_begin();
  63         sha1_base_do_update(desc, data, len,
  64                             (sha1_block_fn *)sha1_transform_asm);
  65         kernel_fpu_end();
  66
  67         return 0;
  68 }
  69
  70 static int sha1_ssse3_finup(struct shash_desc *desc, const u8 *data,
  71                               unsigned int len, u8 *out)
  72 {
  73         if (!irq_fpu_usable())
  74                 return crypto_sha1_finup(desc, data, len, out);
  75
  76         kernel_fpu_begin();
  77         if (len)
  78                 sha1_base_do_update(desc, data, len,
  79                                     (sha1_block_fn *)sha1_transform_asm);
  80         sha1_base_do_finalize(desc, (sha1_block_fn *)sha1_transform_asm);
  81         kernel_fpu_end();
  82
  83         return sha1_base_finish(desc, out);
  84 }
  85
  86 /* Add padding and return the message digest. */
  87 static int sha1_ssse3_final(struct shash_desc *desc, u8 *out)
  88 {
  89         return sha1_ssse3_finup(desc, NULL, 0, out);
  90 }
  91
  92 #ifdef CONFIG_AS_AVX2
  93 static void sha1_apply_transform_avx2(u32 *digest, const char *data,
  94                                 unsigned int rounds)
  95 {
  96         /* Select the optimal transform based on data block size */
  97         if (rounds >= SHA1_AVX2_BLOCK_OPTSIZE)
  98                 sha1_transform_avx2(digest, data, rounds);
  99         else
 100                 sha1_transform_avx(digest, data, rounds);
 101 }
 102 #endif
 103
 104 static struct shash_alg alg = {
 105         .digestsize     =       SHA1_DIGEST_SIZE,
 106         .init           =       sha1_base_init,
 107         .update         =       sha1_ssse3_update,
 108         .final          =       sha1_ssse3_final,
 109         .finup          =       sha1_ssse3_finup,
 110         .descsize       =       sizeof(struct sha1_state),
 111         .base           =       {
 112                 .cra_name       =       "sha1",
 113                 .cra_driver_name=       "sha1-ssse3",
 114                 .cra_priority   =       150,
 115                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 116                 .cra_blocksize  =       SHA1_BLOCK_SIZE,
 117                 .cra_module     =       THIS_MODULE,
 118         }
 119 };
 120
 121 #ifdef CONFIG_AS_AVX
 122 static bool __init avx_usable(void)
 123 {
 124         if (!cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, NULL)) {
 125                 if (cpu_has_avx)
 126                         pr_info("AVX detected but unusable.\n");
 127                 return false;
 128         }
 129
 130         return true;
 131 }
 132
 133 #ifdef CONFIG_AS_AVX2
 134 static bool __init avx2_usable(void)
 135 {
 136         if (avx_usable() && cpu_has_avx2 && boot_cpu_has(X86_FEATURE_BMI1) &&
 137             boot_cpu_has(X86_FEATURE_BMI2))
 138                 return true;
 139
 140         return false;
 141 }
 142 #endif
 143 #endif
 144
 145 static int __init sha1_ssse3_mod_init(void)
 146 {
 147         char *algo_name;
 148
 149         /* test for SSSE3 first */
 150         if (cpu_has_ssse3) {
 151                 sha1_transform_asm = sha1_transform_ssse3;
 152                 algo_name = "SSSE3";
 153         }
 154
 155 #ifdef CONFIG_AS_AVX
 156         /* allow AVX to override SSSE3, it's a little faster */
 157         if (avx_usable()) {
 158                 sha1_transform_asm = sha1_transform_avx;
 159                 algo_name = "AVX";
 160 #ifdef CONFIG_AS_AVX2
 161                 /* allow AVX2 to override AVX, it's a little faster */
 162                 if (avx2_usable()) {
 163                         sha1_transform_asm = sha1_apply_transform_avx2;
 164                         algo_name = "AVX2";
 165                 }
 166 #endif
 167         }
 168 #endif
 169
 170         if (sha1_transform_asm) {
 171                 pr_info("Using %s optimized SHA-1 implementation\n", algo_name);
 172                 return crypto_register_shash(&alg);
 173         }
 174         pr_info("Neither AVX nor AVX2 nor SSSE3 is available/usable.\n");
 175
 176         return -ENODEV;
 177 }
 178
 179 static void __exit sha1_ssse3_mod_fini(void)
 180 {
 181         crypto_unregister_shash(&alg);
 182 }
 183
 184 module_init(sha1_ssse3_mod_init);
 185 module_exit(sha1_ssse3_mod_fini);
 186
 187 MODULE_LICENSE("GPL");
 188 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm, Supplemental SSE3 accelerated");
 189
 190 MODULE_ALIAS_CRYPTO("sha1");