crypto/xxhash_generic.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include <crypto/internal/hash.h>
   4 #include <linux/init.h>
   5 #include <linux/module.h>
   6 #include <linux/xxhash.h>
   7 #include <asm/unaligned.h>
   8
   9 #define XXHASH64_BLOCK_SIZE     32
  10 #define XXHASH64_DIGEST_SIZE    8
  11
  12 struct xxhash64_tfm_ctx {
  13         u64 seed;
  14 };
  15
  16 struct xxhash64_desc_ctx {
  17         struct xxh64_state xxhstate;
  18 };
  19
  20 static int xxhash64_setkey(struct crypto_shash *tfm, const u8 *key,
  21                          unsigned int keylen)
  22 {
  23         struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(tfm);
  24
  25         if (keylen != sizeof(tctx->seed))
  26                 return -EINVAL;
  27         tctx->seed = get_unaligned_le64(key);
  28         return 0;
  29 }
  30
  31 static int xxhash64_init(struct shash_desc *desc)
  32 {
  33         struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
  34         struct xxhash64_desc_ctx *dctx = shash_desc_ctx(desc);
  35
  36         xxh64_reset(&dctx->xxhstate, tctx->seed);
  37
  38         return 0;
  39 }
  40
  41 static int xxhash64_update(struct shash_desc *desc, const u8 *data,
  42                          unsigned int length)
  43 {
  44         struct xxhash64_desc_ctx *dctx = shash_desc_ctx(desc);
  45
  46         xxh64_update(&dctx->xxhstate, data, length);
  47
  48         return 0;
  49 }
  50
  51 static int xxhash64_final(struct shash_desc *desc, u8 *out)
  52 {
  53         struct xxhash64_desc_ctx *dctx = shash_desc_ctx(desc);
  54
  55         put_unaligned_le64(xxh64_digest(&dctx->xxhstate), out);
  56
  57         return 0;
  58 }
  59
  60 static int xxhash64_digest(struct shash_desc *desc, const u8 *data,
  61                          unsigned int length, u8 *out)
  62 {
  63         struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
  64
  65         put_unaligned_le64(xxh64(data, length, tctx->seed), out);
  66
  67         return 0;
  68 }
  69
  70 static struct shash_alg alg = {
  71         .digestsize     = XXHASH64_DIGEST_SIZE,
  72         .setkey         = xxhash64_setkey,
  73         .init           = xxhash64_init,
  74         .update         = xxhash64_update,
  75         .final          = xxhash64_final,
  76         .digest         = xxhash64_digest,
  77         .descsize       = sizeof(struct xxhash64_desc_ctx),
  78         .base           = {
  79                 .cra_name        = "xxhash64",
  80                 .cra_driver_name = "xxhash64-generic",
  81                 .cra_priority    = 100,
  82                 .cra_flags       = CRYPTO_ALG_OPTIONAL_KEY,
  83                 .cra_blocksize   = XXHASH64_BLOCK_SIZE,
  84                 .cra_ctxsize     = sizeof(struct xxhash64_tfm_ctx),
  85                 .cra_module      = THIS_MODULE,
  86         }
  87 };
  88
  89 static int __init xxhash_mod_init(void)
  90 {
  91         return crypto_register_shash(&alg);
  92 }
  93
  94 static void __exit xxhash_mod_fini(void)
  95 {
  96         crypto_unregister_shash(&alg);
  97 }
  98
  99 subsys_initcall(xxhash_mod_init);
 100 module_exit(xxhash_mod_fini);
 101
 102 MODULE_AUTHOR("Nikolay Borisov <nborisov@suse.com>");
 103 MODULE_DESCRIPTION("xxhash calculations wrapper for lib/xxhash.c");
 104 MODULE_LICENSE("GPL");
 105 MODULE_ALIAS_CRYPTO("xxhash64");
 106 MODULE_ALIAS_CRYPTO("xxhash64-generic");