release/src/router/nettle/salsa20.h

   1 /* salsa20.h
   2  *
   3  * The Salsa20 stream cipher.
   4  */
   5
   6 /* nettle, low-level cryptographics library
   7  *
   8  * Copyright (C) 2012 Simon Josefsson
   9  * Copyright (C) 2001 Niels Möller
  10  *
  11  * The nettle library is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU Lesser General Public License as published by
  13  * the Free Software Foundation; either version 2.1 of the License, or (at your
  14  * option) any later version.
  15  *
  16  * The nettle library is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  18  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  19  * License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with the nettle library; see the file COPYING.LIB.  If not, write to
  23  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  24  * MA 02111-1301, USA.
  25  */
  26
  27 #ifndef NETTLE_SALSA20_H_INCLUDED
  28 #define NETTLE_SALSA20_H_INCLUDED
  29
  30 #include "nettle-types.h"
  31
  32 #ifdef __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 /* Name mangling */
  37 #define salsa20_set_key nettle_salsa20_set_key
  38 #define salsa20_set_iv nettle_salsa20_set_iv
  39 #define salsa20_crypt nettle_salsa20_crypt
  40 #define _salsa20_core _nettle_salsa20_core
  41
  42 #define salsa20r12_crypt nettle_salsa20r12_crypt
  43
  44 /* Minimum and maximum keysizes, and a reasonable default. In
  45  * octets.*/
  46 #define SALSA20_MIN_KEY_SIZE 16
  47 #define SALSA20_MAX_KEY_SIZE 32
  48 #define SALSA20_KEY_SIZE 32
  49 #define SALSA20_BLOCK_SIZE 64
  50
  51 #define SALSA20_IV_SIZE 8
  52
  53 #define _SALSA20_INPUT_LENGTH 16
  54
  55 struct salsa20_ctx
  56 {
  57   /* Indices 1-4 and 11-14 holds the key (two identical copies for the
  58      shorter key size), indices 0, 5, 10, 15 are constant, indices 6, 7
  59      are the IV, and indices 8, 9 are the block counter:
  60
  61      C K K K
  62      K C I I
  63      B B C K
  64      K K K C
  65   */
  66   uint32_t input[_SALSA20_INPUT_LENGTH];
  67 };
  68
  69 void
  70 salsa20_set_key(struct salsa20_ctx *ctx,
  71                 unsigned length, const uint8_t *key);
  72
  73 void
  74 salsa20_set_iv(struct salsa20_ctx *ctx, const uint8_t *iv);
  75
  76 void
  77 salsa20_crypt(struct salsa20_ctx *ctx,
  78               unsigned length, uint8_t *dst,
  79               const uint8_t *src);
  80
  81 void
  82 salsa20r12_crypt(struct salsa20_ctx *ctx,
  83                  unsigned length, uint8_t *dst,
  84                  const uint8_t *src);
  85
  86 void
  87 _salsa20_core(uint32_t *dst, const uint32_t *src, unsigned rounds);
  88
  89 #ifdef __cplusplus
  90 }
  91 #endif
  92
  93 #endif /* NETTLE_SALSA20_H_INCLUDED */