crypto/des.h

   1 /* des.h
   2  *
   3  * The des block cipher. And triple des.
   4  */
   5
   6 /* nettle, low-level cryptographics library
   7  *
   8  * Copyright (C) 1992, 2001, Dana L. How, Niels Möller
   9  *
  10  * The nettle library is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 of the License, or (at your
  13  * option) any later version.
  14  *
  15  * The nettle library is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  17  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  18  * License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with the nettle library; see the file COPYING.LIB.  If not, write to
  22  * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  23  * MA 02111-1307, USA.
  24  */
  25
  26 /*
  27  *      des - fast & portable DES encryption & decryption.
  28  *      Copyright (C) 1992  Dana L. How
  29  *      Please see the file `../lib/descore.README' for the complete copyright
  30  *      notice.
  31  *
  32  * Slightly edited by Niels Möller, 1997
  33  */
  34
  35 #ifndef NETTLE_DES_H_INCLUDED
  36 #define NETTLE_DES_H_INCLUDED
  37
  38 /* Namespace mangling.
  39  *
  40  * FIXME: In the long run, all nettle symbols should probably have the
  41  * prefix nettle_, with the appropriate header file defining
  42  * shorthands. */
  43
  44 #define des_set_key nettle_des_set_key
  45
  46 #include <inttypes.h>
  47
  48 #define DES_KEY_SIZE 8
  49 #define DES_BLOCK_SIZE 8
  50
  51 /* Expanded key length */
  52 #define _DES_KEY_LENGTH 32
  53
  54 enum des_error { DES_OK, DES_BAD_PARITY, DES_WEAK_KEY };
  55
  56 struct des_ctx
  57 {
  58   uint32_t key[_DES_KEY_LENGTH];
  59   enum des_error status;
  60 };
  61
  62 /* On success, returns 1 and sets ctx->status to DES_OK (zero). On
  63  * error, returns 0 and sets ctx->status accordingly. */
  64 int
  65 des_set_key(struct des_ctx *ctx, const uint8_t *key);
  66
  67 void
  68 des_encrypt(struct des_ctx *ctx,
  69             unsigned length, uint8_t *dst,
  70             const uint8_t *src);
  71 void
  72 des_decrypt(struct des_ctx *ctx,
  73             unsigned length, uint8_t *dst,
  74             const uint8_t *src);
  75
  76 void
  77 des_fix_parity(unsigned length, uint8_t *dst,
  78                const uint8_t *src);
  79
  80 #define DES3_KEY_SIZE 24
  81 #define DES3_BLOCK_SIZE DES_BLOCK_SIZE
  82
  83 struct des3_ctx
  84 {
  85   struct des_ctx des[3];
  86   enum des_error status;
  87 };
  88
  89
  90 /* On success, returns 1 and sets ctx->status to DES_OK (zero). On
  91  * error, returns 0 and sets ctx->status accordingly. */
  92 int
  93 des3_set_key(struct des3_ctx *ctx, const uint8_t *key);
  94
  95 void
  96 des3_encrypt(struct des3_ctx *ctx,
  97             unsigned length, uint8_t *dst,
  98             const uint8_t *src);
  99 void
 100 des3_decrypt(struct des3_ctx *ctx,
 101             unsigned length, uint8_t *dst,
 102             const uint8_t *src);
 103
 104 #endif /* NETTLE_DES_H_INCLUDED */