include/crypto/internal/blake2s.h

   1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
   2 /*
   3  * Helper functions for BLAKE2s implementations.
   4  * Keep this in sync with the corresponding BLAKE2b header.
   5  */
   6
   7 #ifndef _CRYPTO_INTERNAL_BLAKE2S_H
   8 #define _CRYPTO_INTERNAL_BLAKE2S_H
   9
  10 #include <crypto/blake2s.h>
  11 #include <crypto/internal/hash.h>
  12 #include <linux/string.h>
  13
  14 void blake2s_compress_generic(struct blake2s_state *state, const u8 *block,
  15                               size_t nblocks, const u32 inc);
  16
  17 void blake2s_compress(struct blake2s_state *state, const u8 *block,
  18                       size_t nblocks, const u32 inc);
  19
  20 bool blake2s_selftest(void);
  21
  22 static inline void blake2s_set_lastblock(struct blake2s_state *state)
  23 {
  24         state->f[0] = -1;
  25 }
  26
  27 /* Helper functions for BLAKE2s shared by the library and shash APIs */
  28
  29 static __always_inline void
  30 __blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen,
  31                  bool force_generic)
  32 {
  33         const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
  34
  35         if (unlikely(!inlen))
  36                 return;
  37         if (inlen > fill) {
  38                 memcpy(state->buf + state->buflen, in, fill);
  39                 if (force_generic)
  40                         blake2s_compress_generic(state, state->buf, 1,
  41                                                  BLAKE2S_BLOCK_SIZE);
  42                 else
  43                         blake2s_compress(state, state->buf, 1,
  44                                          BLAKE2S_BLOCK_SIZE);
  45                 state->buflen = 0;
  46                 in += fill;
  47                 inlen -= fill;
  48         }
  49         if (inlen > BLAKE2S_BLOCK_SIZE) {
  50                 const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
  51                 /* Hash one less (full) block than strictly possible */
  52                 if (force_generic)
  53                         blake2s_compress_generic(state, in, nblocks - 1,
  54                                                  BLAKE2S_BLOCK_SIZE);
  55                 else
  56                         blake2s_compress(state, in, nblocks - 1,
  57                                          BLAKE2S_BLOCK_SIZE);
  58                 in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
  59                 inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
  60         }
  61         memcpy(state->buf + state->buflen, in, inlen);
  62         state->buflen += inlen;
  63 }
  64
  65 static __always_inline void
  66 __blake2s_final(struct blake2s_state *state, u8 *out, bool force_generic)
  67 {
  68         blake2s_set_lastblock(state);
  69         memset(state->buf + state->buflen, 0,
  70                BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
  71         if (force_generic)
  72                 blake2s_compress_generic(state, state->buf, 1, state->buflen);
  73         else
  74                 blake2s_compress(state, state->buf, 1, state->buflen);
  75         cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
  76         memcpy(out, state->h, state->outlen);
  77 }
  78
  79 /* Helper functions for shash implementations of BLAKE2s */
  80
  81 struct blake2s_tfm_ctx {
  82         u8 key[BLAKE2S_KEY_SIZE];
  83         unsigned int keylen;
  84 };
  85
  86 static inline int crypto_blake2s_setkey(struct crypto_shash *tfm,
  87                                         const u8 *key, unsigned int keylen)
  88 {
  89         struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(tfm);
  90
  91         if (keylen == 0 || keylen > BLAKE2S_KEY_SIZE)
  92                 return -EINVAL;
  93
  94         memcpy(tctx->key, key, keylen);
  95         tctx->keylen = keylen;
  96
  97         return 0;
  98 }
  99
 100 static inline int crypto_blake2s_init(struct shash_desc *desc)
 101 {
 102         const struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
 103         struct blake2s_state *state = shash_desc_ctx(desc);
 104         unsigned int outlen = crypto_shash_digestsize(desc->tfm);
 105
 106         __blake2s_init(state, outlen, tctx->key, tctx->keylen);
 107         return 0;
 108 }
 109
 110 static inline int crypto_blake2s_update(struct shash_desc *desc,
 111                                         const u8 *in, unsigned int inlen,
 112                                         bool force_generic)
 113 {
 114         struct blake2s_state *state = shash_desc_ctx(desc);
 115
 116         __blake2s_update(state, in, inlen, force_generic);
 117         return 0;
 118 }
 119
 120 static inline int crypto_blake2s_final(struct shash_desc *desc, u8 *out,
 121                                        bool force_generic)
 122 {
 123         struct blake2s_state *state = shash_desc_ctx(desc);
 124
 125         __blake2s_final(state, out, force_generic);
 126         return 0;
 127 }
 128
 129 #endif /* _CRYPTO_INTERNAL_BLAKE2S_H */