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/cpufeature.h>
  15 #include <linux/crypto.h>
  16 #include <linux/module.h>
  17
  18 #include <asm/hwcap.h>
  19 #include <asm/simd.h>
  20 #include <asm/neon.h>
  21 #include <asm/unaligned.h>
  22
  23 #include "sha256_glue.h"
  24
  25 MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
  26 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
  27 MODULE_LICENSE("GPL v2");
  28
  29 asmlinkage void sha2_ce_transform(struct sha256_state *sst, u8 const *src,
  30                                   int blocks);
  31
  32 static int sha2_ce_update(struct shash_desc *desc, const u8 *data,
  33                           unsigned int len)
  34 {
  35         struct sha256_state *sctx = shash_desc_ctx(desc);
  36
  37         if (!may_use_simd() ||
  38             (sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
  39                 return crypto_sha256_arm_update(desc, data, len);
  40
  41         kernel_neon_begin();
  42         sha256_base_do_update(desc, data, len,
  43                               (sha256_block_fn *)sha2_ce_transform);
  44         kernel_neon_end();
  45
  46         return 0;
  47 }
  48
  49 static int sha2_ce_finup(struct shash_desc *desc, const u8 *data,
  50                          unsigned int len, u8 *out)
  51 {
  52         if (!may_use_simd())
  53                 return crypto_sha256_arm_finup(desc, data, len, out);
  54
  55         kernel_neon_begin();
  56         if (len)
  57                 sha256_base_do_update(desc, data, len,
  58                                       (sha256_block_fn *)sha2_ce_transform);
  59         sha256_base_do_finalize(desc, (sha256_block_fn *)sha2_ce_transform);
  60         kernel_neon_end();
  61
  62         return sha256_base_finish(desc, out);
  63 }
  64
  65 static int sha2_ce_final(struct shash_desc *desc, u8 *out)
  66 {
  67         return sha2_ce_finup(desc, NULL, 0, out);
  68 }
  69
  70 static struct shash_alg algs[] = { {
  71         .init                   = sha224_base_init,
  72         .update                 = sha2_ce_update,
  73         .final                  = sha2_ce_final,
  74         .finup                  = sha2_ce_finup,
  75         .descsize               = sizeof(struct sha256_state),
  76         .digestsize             = SHA224_DIGEST_SIZE,
  77         .base                   = {
  78                 .cra_name               = "sha224",
  79                 .cra_driver_name        = "sha224-ce",
  80                 .cra_priority           = 300,
  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_blocksize          = SHA256_BLOCK_SIZE,
  96                 .cra_module             = THIS_MODULE,
  97         }
  98 } };
  99
 100 static int __init sha2_ce_mod_init(void)
 101 {
 102         return crypto_register_shashes(algs, ARRAY_SIZE(algs));
 103 }
 104
 105 static void __exit sha2_ce_mod_fini(void)
 106 {
 107         crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
 108 }
 109
 110 module_cpu_feature_match(SHA2, sha2_ce_mod_init);
 111 module_exit(sha2_ce_mod_fini);