kernel/arch/arm/crypto/sha2-ce-glue.c

   1 /*
   2  * sha2-ce-glue.c - SHA-224/SHA-256 using ARMv8 Crypto Extensions
   3  *
   4  * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <crypto/internal/hash.h>
  12 #include <crypto/sha.h>
  13 #include <crypto/sha256_base.h>
  14 #include <linux/crypto.h>
  15 #include <linux/module.h>
  16
  17 #include <asm/hwcap.h>
  18 #include <asm/simd.h>
  19 #include <asm/neon.h>
  20 #include <asm/unaligned.h>
  21
  22 #include "sha256_glue.h"
  23
  24 MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
  25 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
  26 MODULE_LICENSE("GPL v2");
  27
  28 asmlinkage void sha2_ce_transform(struct sha256_state *sst, u8 const *src,
  29                                   int blocks);
  30
  31 static int sha2_ce_update(struct shash_desc *desc, const u8 *data,
  32                           unsigned int len)
  33 {
  34         struct sha256_state *sctx = shash_desc_ctx(desc);
  35
  36         if (!may_use_simd() ||
  37             (sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
  38                 return crypto_sha256_arm_update(desc, data, len);
  39
  40         kernel_neon_begin();
  41         sha256_base_do_update(desc, data, len,
  42                               (sha256_block_fn *)sha2_ce_transform);
  43         kernel_neon_end();
  44
  45         return 0;
  46 }
  47
  48 static int sha2_ce_finup(struct shash_desc *desc, const u8 *data,
  49                          unsigned int len, u8 *out)
  50 {
  51         if (!may_use_simd())
  52                 return crypto_sha256_arm_finup(desc, data, len, out);
  53
  54         kernel_neon_begin();
  55         if (len)
  56                 sha256_base_do_update(desc, data, len,
  57                                       (sha256_block_fn *)sha2_ce_transform);
  58         sha256_base_do_finalize(desc, (sha256_block_fn *)sha2_ce_transform);
  59         kernel_neon_end();
  60
  61         return sha256_base_finish(desc, out);
  62 }
  63
  64 static int sha2_ce_final(struct shash_desc *desc, u8 *out)
  65 {
  66         return sha2_ce_finup(desc, NULL, 0, out);
  67 }
  68
  69 static struct shash_alg algs[] = { {
  70         .init                   = sha224_base_init,
  71         .update                 = sha2_ce_update,
  72         .final                  = sha2_ce_final,
  73         .finup                  = sha2_ce_finup,
  74         .descsize               = sizeof(struct sha256_state),
  75         .digestsize             = SHA224_DIGEST_SIZE,
  76         .base                   = {
  77                 .cra_name               = "sha224",
  78                 .cra_driver_name        = "sha224-ce",
  79                 .cra_priority           = 300,
  80                 .cra_flags              = CRYPTO_ALG_TYPE_SHASH,
  81                 .cra_blocksize          = SHA256_BLOCK_SIZE,
  82                 .cra_module             = THIS_MODULE,
  83         }
  84 }, {
  85         .init                   = sha256_base_init,
  86         .update                 = sha2_ce_update,
  87         .final                  = sha2_ce_final,
  88         .finup                  = sha2_ce_finup,
  89         .descsize               = sizeof(struct sha256_state),
  90         .digestsize             = SHA256_DIGEST_SIZE,
  91         .base                   = {
  92                 .cra_name               = "sha256",
  93                 .cra_driver_name        = "sha256-ce",
  94                 .cra_priority           = 300,
  95                 .cra_flags              = CRYPTO_ALG_TYPE_SHASH,
  96                 .cra_blocksize          = SHA256_BLOCK_SIZE,
  97                 .cra_module             = THIS_MODULE,
  98         }
  99 } };
 100
 101 static int __init sha2_ce_mod_init(void)
 102 {
 103         if (!(elf_hwcap2 & HWCAP2_SHA2))
 104                 return -ENODEV;
 105         return crypto_register_shashes(algs, ARRAY_SIZE(algs));
 106 }
 107
 108 static void __exit sha2_ce_mod_fini(void)
 109 {
 110         crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
 111 }
 112
 113 module_init(sha2_ce_mod_init);
 114 module_exit(sha2_ce_mod_fini);