/* Arc4random definition used on TLS.
Copyright (C) 2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
. */
#ifndef _CHACHA20_H
#define _CHACHA20_H
#include
#include
/* Internal ChaCha20 state. */
#define CHACHA20_STATE_LEN 16
#define CHACHA20_BLOCK_SIZE 64
/* Maximum number bytes until reseed (16 MB). */
#define CHACHA20_RESEED_SIZE (16 * 1024 * 1024)
/* Internal arc4random buffer, used on each feedback step so offer some
backtracking protection and to allow better used of vectorized
chacha20 implementations. */
#define CHACHA20_BUFSIZE (8 * CHACHA20_BLOCK_SIZE)
_Static_assert (CHACHA20_BUFSIZE >= CHACHA20_BLOCK_SIZE + CHACHA20_BLOCK_SIZE,
"CHACHA20_BUFSIZE < CHACHA20_BLOCK_SIZE + CHACHA20_BLOCK_SIZE");
struct arc4random_state_t
{
uint32_t ctx[CHACHA20_STATE_LEN];
size_t have;
size_t count;
uint8_t buf[CHACHA20_BUFSIZE];
};
#endif