arch/x86/crypto/nhpoly1305-avx2-glue.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
   4  * (AVX2 accelerated version)
   5  *
   6  * Copyright 2018 Google LLC
   7  */
   8
   9 #include <crypto/internal/hash.h>
  10 #include <crypto/nhpoly1305.h>
  11 #include <linux/module.h>
  12 #include <asm/fpu/api.h>
  13
  14 asmlinkage void nh_avx2(const u32 *key, const u8 *message, size_t message_len,
  15                         u8 hash[NH_HASH_BYTES]);
  16
  17 /* wrapper to avoid indirect call to assembly, which doesn't work with CFI */
  18 static void _nh_avx2(const u32 *key, const u8 *message, size_t message_len,
  19                      __le64 hash[NH_NUM_PASSES])
  20 {
  21         nh_avx2(key, message, message_len, (u8 *)hash);
  22 }
  23
  24 static int nhpoly1305_avx2_update(struct shash_desc *desc,
  25                                   const u8 *src, unsigned int srclen)
  26 {
  27         if (srclen < 64 || !irq_fpu_usable())
  28                 return crypto_nhpoly1305_update(desc, src, srclen);
  29
  30         do {
  31                 unsigned int n = min_t(unsigned int, srclen, PAGE_SIZE);
  32
  33                 kernel_fpu_begin();
  34                 crypto_nhpoly1305_update_helper(desc, src, n, _nh_avx2);
  35                 kernel_fpu_end();
  36                 src += n;
  37                 srclen -= n;
  38         } while (srclen);
  39         return 0;
  40 }
  41
  42 static struct shash_alg nhpoly1305_alg = {
  43         .base.cra_name          = "nhpoly1305",
  44         .base.cra_driver_name   = "nhpoly1305-avx2",
  45         .base.cra_priority      = 300,
  46         .base.cra_ctxsize       = sizeof(struct nhpoly1305_key),
  47         .base.cra_module        = THIS_MODULE,
  48         .digestsize             = POLY1305_DIGEST_SIZE,
  49         .init                   = crypto_nhpoly1305_init,
  50         .update                 = nhpoly1305_avx2_update,
  51         .final                  = crypto_nhpoly1305_final,
  52         .setkey                 = crypto_nhpoly1305_setkey,
  53         .descsize               = sizeof(struct nhpoly1305_state),
  54 };
  55
  56 static int __init nhpoly1305_mod_init(void)
  57 {
  58         if (!boot_cpu_has(X86_FEATURE_AVX2) ||
  59             !boot_cpu_has(X86_FEATURE_OSXSAVE))
  60                 return -ENODEV;
  61
  62         return crypto_register_shash(&nhpoly1305_alg);
  63 }
  64
  65 static void __exit nhpoly1305_mod_exit(void)
  66 {
  67         crypto_unregister_shash(&nhpoly1305_alg);
  68 }
  69
  70 module_init(nhpoly1305_mod_init);
  71 module_exit(nhpoly1305_mod_exit);
  72
  73 MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (AVX2-accelerated)");
  74 MODULE_LICENSE("GPL v2");
  75 MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
  76 MODULE_ALIAS_CRYPTO("nhpoly1305");
  77 MODULE_ALIAS_CRYPTO("nhpoly1305-avx2");