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 #include <asm/xcr.h>
  34 #include <asm/fpu/xstate.h>
  35
  36
  37 asmlinkage void sha1_transform_ssse3(u32 *digest, const char *data,
  38                                      unsigned int rounds);
  39 #ifdef CONFIG_AS_AVX
  40 asmlinkage void sha1_transform_avx(u32 *digest, const char *data,
  41                                    unsigned int rounds);
  42 #endif
  43 #ifdef CONFIG_AS_AVX2
  44 #define SHA1_AVX2_BLOCK_OPTSIZE 4       /* optimal 4*64 bytes of SHA1 blocks */
  45
  46 asmlinkage void sha1_transform_avx2(u32 *digest, const char *data,
  47                                     unsigned int rounds);
  48 #endif
  49
  50 static void (*sha1_transform_asm)(u32 *, const char *, unsigned int);
  51
  52 static int sha1_ssse3_update(struct shash_desc *desc, const u8 *data,
  53                              unsigned int len)
  54 {
  55         struct sha1_state *sctx = shash_desc_ctx(desc);
  56
  57         if (!irq_fpu_usable() ||
  58             (sctx->count % SHA1_BLOCK_SIZE) + len < SHA1_BLOCK_SIZE)
  59                 return crypto_sha1_update(desc, data, len);
  60
  61         /* make sure casting to sha1_block_fn() is safe */
  62         BUILD_BUG_ON(offsetof(struct sha1_state, state) != 0);
  63
  64         kernel_fpu_begin();
  65         sha1_base_do_update(desc, data, len,
  66                             (sha1_block_fn *)sha1_transform_asm);
  67         kernel_fpu_end();
  68
  69         return 0;
  70 }
  71
  72 static int sha1_ssse3_finup(struct shash_desc *desc, const u8 *data,
  73                               unsigned int len, u8 *out)
  74 {
  75         if (!irq_fpu_usable())
  76                 return crypto_sha1_finup(desc, data, len, out);
  77
  78         kernel_fpu_begin();
  79         if (len)
  80                 sha1_base_do_update(desc, data, len,
  81                                     (sha1_block_fn *)sha1_transform_asm);
  82         sha1_base_do_finalize(desc, (sha1_block_fn *)sha1_transform_asm);
  83         kernel_fpu_end();
  84
  85         return sha1_base_finish(desc, out);
  86 }
  87
  88 /* Add padding and return the message digest. */
  89 static int sha1_ssse3_final(struct shash_desc *desc, u8 *out)
  90 {
  91         return sha1_ssse3_finup(desc, NULL, 0, out);
  92 }
  93
  94 #ifdef CONFIG_AS_AVX2
  95 static void sha1_apply_transform_avx2(u32 *digest, const char *data,
  96                                 unsigned int rounds)
  97 {
  98         /* Select the optimal transform based on data block size */
  99         if (rounds >= SHA1_AVX2_BLOCK_OPTSIZE)
 100                 sha1_transform_avx2(digest, data, rounds);
 101         else
 102                 sha1_transform_avx(digest, data, rounds);
 103 }
 104 #endif
 105
 106 static struct shash_alg alg = {
 107         .digestsize     =       SHA1_DIGEST_SIZE,
 108         .init           =       sha1_base_init,
 109         .update         =       sha1_ssse3_update,
 110         .final          =       sha1_ssse3_final,
 111         .finup          =       sha1_ssse3_finup,
 112         .descsize       =       sizeof(struct sha1_state),
 113         .base           =       {
 114                 .cra_name       =       "sha1",
 115                 .cra_driver_name=       "sha1-ssse3",
 116                 .cra_priority   =       150,
 117                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 118                 .cra_blocksize  =       SHA1_BLOCK_SIZE,
 119                 .cra_module     =       THIS_MODULE,
 120         }
 121 };
 122
 123 #ifdef CONFIG_AS_AVX
 124 static bool __init avx_usable(void)
 125 {
 126         u64 xcr0;
 127
 128         if (!cpu_has_avx || !cpu_has_osxsave)
 129                 return false;
 130
 131         xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
 132         if ((xcr0 & (XSTATE_SSE | XSTATE_YMM)) != (XSTATE_SSE | XSTATE_YMM)) {
 133                 pr_info("AVX detected but unusable.\n");
 134
 135                 return false;
 136         }
 137
 138         return true;
 139 }
 140
 141 #ifdef CONFIG_AS_AVX2
 142 static bool __init avx2_usable(void)
 143 {
 144         if (avx_usable() && cpu_has_avx2 && boot_cpu_has(X86_FEATURE_BMI1) &&
 145             boot_cpu_has(X86_FEATURE_BMI2))
 146                 return true;
 147
 148         return false;
 149 }
 150 #endif
 151 #endif
 152
 153 static int __init sha1_ssse3_mod_init(void)
 154 {
 155         char *algo_name;
 156
 157         /* test for SSSE3 first */
 158         if (cpu_has_ssse3) {
 159                 sha1_transform_asm = sha1_transform_ssse3;
 160                 algo_name = "SSSE3";
 161         }
 162
 163 #ifdef CONFIG_AS_AVX
 164         /* allow AVX to override SSSE3, it's a little faster */
 165         if (avx_usable()) {
 166                 sha1_transform_asm = sha1_transform_avx;
 167                 algo_name = "AVX";
 168 #ifdef CONFIG_AS_AVX2
 169                 /* allow AVX2 to override AVX, it's a little faster */
 170                 if (avx2_usable()) {
 171                         sha1_transform_asm = sha1_apply_transform_avx2;
 172                         algo_name = "AVX2";
 173                 }
 174 #endif
 175         }
 176 #endif
 177
 178         if (sha1_transform_asm) {
 179                 pr_info("Using %s optimized SHA-1 implementation\n", algo_name);
 180                 return crypto_register_shash(&alg);
 181         }
 182         pr_info("Neither AVX nor AVX2 nor SSSE3 is available/usable.\n");
 183
 184         return -ENODEV;
 185 }
 186
 187 static void __exit sha1_ssse3_mod_fini(void)
 188 {
 189         crypto_unregister_shash(&alg);
 190 }
 191
 192 module_init(sha1_ssse3_mod_init);
 193 module_exit(sha1_ssse3_mod_fini);
 194
 195 MODULE_LICENSE("GPL");
 196 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm, Supplemental SSE3 accelerated");
 197
 198 MODULE_ALIAS_CRYPTO("sha1");