/* camellia-invert-key.c
 *
 * Inverting a key means reversing order of subkeys.
 */

/* nettle, low-level cryptographics library
 *
 * Copyright (C) 2010 Niels Möller
 *  
 * The nettle 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 nettle 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 nettle library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02111-1301, USA.
 */

#if HAVE_CONFIG_H
# include "config.h"
#endif

#include "camellia-internal.h"

#define SWAP(a, b) \
do { uint64_t t_swap = (a); (a) = (b); (b) = t_swap; } while(0)

void
_camellia_invert_key(unsigned nkeys,
		     uint64_t *dst, const uint64_t *src)
{
  unsigned i;
  if (dst == src)
    for (i = 0; i < nkeys - 1 - i; i++)
	SWAP (dst[i], dst[nkeys - 1- i]);
  else
    for (i = 0; i < nkeys; i++)
      dst[i] = src[nkeys - 1 - i];
}