lgl/des.h

   1 /* des.h --- DES cipher implementation.
   2  * Copyright (C) 2005, 2007 Free Software Foundation, Inc.
   3  *
   4  * This file is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License as published
   6  * by the Free Software Foundation; either version 2.1, or (at your
   7  * option) any later version.
   8  *
   9  * This file is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public License
  15  * along with this file; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA.
  18  *
  19  */
  20
  21 /* Adapted for gnulib by Simon Josefsson, based on Libgcrypt. */
  22
  23 #ifndef DES_H
  24 # define DES_H
  25
  26 #include <stddef.h>
  27 #include <stdint.h>
  28 #include <stdbool.h>
  29
  30 /*
  31  * Encryption/Decryption context of DES
  32  */
  33 typedef struct
  34 {
  35   uint32_t encrypt_subkeys[32];
  36   uint32_t decrypt_subkeys[32];
  37 } gl_des_ctx;
  38
  39 /*
  40  * Encryption/Decryption context of Triple-DES
  41  */
  42 typedef struct
  43 {
  44   uint32_t encrypt_subkeys[96];
  45   uint32_t decrypt_subkeys[96];
  46 } gl_3des_ctx;
  47
  48 /* Check whether the 8 byte key is weak.  Does not check the parity
  49  * bits of the key but simple ignore them. */
  50 extern bool
  51 gl_des_is_weak_key (const char * key);
  52
  53 /*
  54  * DES
  55  * ---
  56  */
  57
  58 /* Fill a DES context CTX with subkeys calculated from 64bit KEY.
  59  * Does not check parity bits, but simply ignore them.  Does not check
  60  * for weak keys. */
  61 extern void
  62 gl_des_setkey (gl_des_ctx *ctx, const char * key);
  63
  64 /* Fill a DES context CTX with subkeys calculated from 64bit KEY, with
  65  * weak key checking.  Does not check parity bits, but simply ignore
  66  * them. */
  67 extern bool
  68 gl_des_makekey (gl_des_ctx *ctx, const char * key, size_t keylen);
  69
  70 /* Electronic Codebook Mode DES encryption/decryption of data
  71  * according to 'mode'. */
  72 extern void
  73 gl_des_ecb_crypt (gl_des_ctx *ctx, const char * from,  char * to, int mode);
  74
  75 #define gl_des_ecb_encrypt(ctx, from, to)  gl_des_ecb_crypt(ctx, from, to, 0)
  76 #define gl_des_ecb_decrypt(ctx, from, to)  gl_des_ecb_crypt(ctx, from, to, 1)
  77
  78 /* Triple-DES
  79  * ----------
  80  */
  81
  82 /* Fill a Triple-DES context CTX with subkeys calculated from two
  83  * 64bit keys in KEY1 and KEY2.  Does not check the parity bits of the
  84  * keys, but simply ignore them.  Does not check for weak keys. */
  85 extern void
  86 gl_3des_set2keys (gl_3des_ctx *ctx,
  87                   const char * key1,
  88                   const char * key2);
  89
  90 /*
  91  * Fill a Triple-DES context CTX with subkeys calculated from three
  92  * 64bit keys in KEY1, KEY2 and KEY3.  Does not check the parity bits
  93  * of the keys, but simply ignore them.  Does not check for weak
  94  * keys. */
  95 extern void
  96 gl_3des_set3keys (gl_3des_ctx *ctx,
  97                   const char * key1,
  98                   const char * key2,
  99                   const char * key3);
 100
 101 /* Fill a Triple-DES context CTX with subkeys calculated from three
 102  * concatenated 64bit keys in KEY, with weak key checking.  Does not
 103  * check the parity bits of the keys, but simply ignore them. */
 104 extern bool
 105 gl_3des_makekey (gl_3des_ctx *ctx,
 106                  const char * key,
 107                  size_t keylen);
 108
 109 /* Electronic Codebook Mode Triple-DES encryption/decryption of data
 110  * according to 'mode'.  Sometimes this mode is named 'EDE' mode
 111  * (Encryption-Decryption-Encryption). */
 112 extern void
 113 gl_3des_ecb_crypt (gl_3des_ctx *ctx,
 114                    const char * from,
 115                    char * to,
 116                    int mode);
 117
 118 #define gl_3des_ecb_encrypt(ctx, from, to) gl_3des_ecb_crypt(ctx,from,to,0)
 119 #define gl_3des_ecb_decrypt(ctx, from, to) gl_3des_ecb_crypt(ctx,from,to,1)
 120
 121 #endif /* DES_H */