crypto/blake2s_generic.c

   1 // SPDX-License-Identifier: GPL-2.0 OR MIT
   2 /*
   3  * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
   4  */
   5
   6 #include <crypto/internal/blake2s.h>
   7 #include <crypto/internal/hash.h>
   8
   9 #include <linux/types.h>
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12
  13 static int crypto_blake2s_setkey(struct crypto_shash *tfm, const u8 *key,
  14                                  unsigned int keylen)
  15 {
  16         struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(tfm);
  17
  18         if (keylen == 0 || keylen > BLAKE2S_KEY_SIZE)
  19                 return -EINVAL;
  20
  21         memcpy(tctx->key, key, keylen);
  22         tctx->keylen = keylen;
  23
  24         return 0;
  25 }
  26
  27 static int crypto_blake2s_init(struct shash_desc *desc)
  28 {
  29         struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
  30         struct blake2s_state *state = shash_desc_ctx(desc);
  31         const int outlen = crypto_shash_digestsize(desc->tfm);
  32
  33         if (tctx->keylen)
  34                 blake2s_init_key(state, outlen, tctx->key, tctx->keylen);
  35         else
  36                 blake2s_init(state, outlen);
  37
  38         return 0;
  39 }
  40
  41 static int crypto_blake2s_update(struct shash_desc *desc, const u8 *in,
  42                                  unsigned int inlen)
  43 {
  44         struct blake2s_state *state = shash_desc_ctx(desc);
  45         const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
  46
  47         if (unlikely(!inlen))
  48                 return 0;
  49         if (inlen > fill) {
  50                 memcpy(state->buf + state->buflen, in, fill);
  51                 blake2s_compress_generic(state, state->buf, 1, BLAKE2S_BLOCK_SIZE);
  52                 state->buflen = 0;
  53                 in += fill;
  54                 inlen -= fill;
  55         }
  56         if (inlen > BLAKE2S_BLOCK_SIZE) {
  57                 const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
  58                 /* Hash one less (full) block than strictly possible */
  59                 blake2s_compress_generic(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE);
  60                 in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
  61                 inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
  62         }
  63         memcpy(state->buf + state->buflen, in, inlen);
  64         state->buflen += inlen;
  65
  66         return 0;
  67 }
  68
  69 static int crypto_blake2s_final(struct shash_desc *desc, u8 *out)
  70 {
  71         struct blake2s_state *state = shash_desc_ctx(desc);
  72
  73         blake2s_set_lastblock(state);
  74         memset(state->buf + state->buflen, 0,
  75                BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
  76         blake2s_compress_generic(state, state->buf, 1, state->buflen);
  77         cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
  78         memcpy(out, state->h, state->outlen);
  79         memzero_explicit(state, sizeof(*state));
  80
  81         return 0;
  82 }
  83
  84 #define BLAKE2S_ALG(name, driver_name, digest_size)                     \
  85         {                                                               \
  86                 .base.cra_name          = name,                         \
  87                 .base.cra_driver_name   = driver_name,                  \
  88                 .base.cra_priority      = 100,                          \
  89                 .base.cra_flags         = CRYPTO_ALG_OPTIONAL_KEY,      \
  90                 .base.cra_blocksize     = BLAKE2S_BLOCK_SIZE,           \
  91                 .base.cra_ctxsize       = sizeof(struct blake2s_tfm_ctx), \
  92                 .base.cra_module        = THIS_MODULE,                  \
  93                 .digestsize             = digest_size,                  \
  94                 .setkey                 = crypto_blake2s_setkey,        \
  95                 .init                   = crypto_blake2s_init,          \
  96                 .update                 = crypto_blake2s_update,        \
  97                 .final                  = crypto_blake2s_final,         \
  98                 .descsize               = sizeof(struct blake2s_state), \
  99         }
 100
 101 static struct shash_alg blake2s_algs[] = {
 102         BLAKE2S_ALG("blake2s-128", "blake2s-128-generic",
 103                     BLAKE2S_128_HASH_SIZE),
 104         BLAKE2S_ALG("blake2s-160", "blake2s-160-generic",
 105                     BLAKE2S_160_HASH_SIZE),
 106         BLAKE2S_ALG("blake2s-224", "blake2s-224-generic",
 107                     BLAKE2S_224_HASH_SIZE),
 108         BLAKE2S_ALG("blake2s-256", "blake2s-256-generic",
 109                     BLAKE2S_256_HASH_SIZE),
 110 };
 111
 112 static int __init blake2s_mod_init(void)
 113 {
 114         return crypto_register_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
 115 }
 116
 117 static void __exit blake2s_mod_exit(void)
 118 {
 119         crypto_unregister_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
 120 }
 121
 122 subsys_initcall(blake2s_mod_init);
 123 module_exit(blake2s_mod_exit);
 124
 125 MODULE_ALIAS_CRYPTO("blake2s-128");
 126 MODULE_ALIAS_CRYPTO("blake2s-128-generic");
 127 MODULE_ALIAS_CRYPTO("blake2s-160");
 128 MODULE_ALIAS_CRYPTO("blake2s-160-generic");
 129 MODULE_ALIAS_CRYPTO("blake2s-224");
 130 MODULE_ALIAS_CRYPTO("blake2s-224-generic");
 131 MODULE_ALIAS_CRYPTO("blake2s-256");
 132 MODULE_ALIAS_CRYPTO("blake2s-256-generic");
 133 MODULE_LICENSE("GPL v2");