FXRNG_HASH_SZ
rc = blake2b_init(&h->state, FXRNG_HASH_SZ);
fxrng_hash_finish(struct fxrng_hash *h, uint8_t buf[static FXRNG_HASH_SZ], size_t sz)
uint8_t hash[FXRNG_HASH_SZ];
uint8_t hash[FXRNG_HASH_SZ * FXRNG_NPOOLS];
fxrng_hash_finish(&fxent_pool[i], hash + i * FXRNG_HASH_SZ,
FXRNG_HASH_SZ);
fxrng_brng_reseed(hash, n * FXRNG_HASH_SZ);
explicit_bzero(hash, n * FXRNG_HASH_SZ);
uint8_t hash_out[FXRNG_HASH_SZ];
_Static_assert(FX_CHACHA20_KEYSIZE <= FXRNG_HASH_SZ, "");