arch/arm/crypto/nhpoly1305-neon-glue.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
   4  * (NEON accelerated version)
   5  *
   6  * Copyright 2018 Google LLC
   7  */
   8
   9 #include <asm/neon.h>
  10 #include <asm/simd.h>
  11 #include <crypto/internal/hash.h>
  12 #include <crypto/internal/simd.h>
  13 #include <crypto/nhpoly1305.h>
  14 #include <linux/module.h>
  15
  16 asmlinkage void nh_neon(const u32 *key, const u8 *message, size_t message_len,
  17                         u8 hash[NH_HASH_BYTES]);
  18
  19 /* wrapper to avoid indirect call to assembly, which doesn't work with CFI */
  20 static void _nh_neon(const u32 *key, const u8 *message, size_t message_len,
  21                      __le64 hash[NH_NUM_PASSES])
  22 {
  23         nh_neon(key, message, message_len, (u8 *)hash);
  24 }
  25
  26 static int nhpoly1305_neon_update(struct shash_desc *desc,
  27                                   const u8 *src, unsigned int srclen)
  28 {
  29         if (srclen < 64 || !crypto_simd_usable())
  30                 return crypto_nhpoly1305_update(desc, src, srclen);
  31
  32         do {
  33                 unsigned int n = min_t(unsigned int, srclen, SZ_4K);
  34
  35                 kernel_neon_begin();
  36                 crypto_nhpoly1305_update_helper(desc, src, n, _nh_neon);
  37                 kernel_neon_end();
  38                 src += n;
  39                 srclen -= n;
  40         } while (srclen);
  41         return 0;
  42 }
  43
  44 static struct shash_alg nhpoly1305_alg = {
  45         .base.cra_name          = "nhpoly1305",
  46         .base.cra_driver_name   = "nhpoly1305-neon",
  47         .base.cra_priority      = 200,
  48         .base.cra_ctxsize       = sizeof(struct nhpoly1305_key),
  49         .base.cra_module        = THIS_MODULE,
  50         .digestsize             = POLY1305_DIGEST_SIZE,
  51         .init                   = crypto_nhpoly1305_init,
  52         .update                 = nhpoly1305_neon_update,
  53         .final                  = crypto_nhpoly1305_final,
  54         .setkey                 = crypto_nhpoly1305_setkey,
  55         .descsize               = sizeof(struct nhpoly1305_state),
  56 };
  57
  58 static int __init nhpoly1305_mod_init(void)
  59 {
  60         if (!(elf_hwcap & HWCAP_NEON))
  61                 return -ENODEV;
  62
  63         return crypto_register_shash(&nhpoly1305_alg);
  64 }
  65
  66 static void __exit nhpoly1305_mod_exit(void)
  67 {
  68         crypto_unregister_shash(&nhpoly1305_alg);
  69 }
  70
  71 module_init(nhpoly1305_mod_init);
  72 module_exit(nhpoly1305_mod_exit);
  73
  74 MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (NEON-accelerated)");
  75 MODULE_LICENSE("GPL v2");
  76 MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
  77 MODULE_ALIAS_CRYPTO("nhpoly1305");
  78 MODULE_ALIAS_CRYPTO("nhpoly1305-neon");