| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: idea.h,v 1.2 1997/08/04 10:24:22 mdw Exp $ |
| 4 | * |
| 5 | * IDEA encryption routines |
| 6 | * Based on Straylight ARM assembler routines |
| 7 | * |
| 8 | * (c) 1996, 1997 Mark Wooding |
| 9 | */ |
| 10 | |
| 11 | /*----- Licensing notice --------------------------------------------------* |
| 12 | * |
| 13 | * This file is part of `become' |
| 14 | * |
| 15 | * `Become' is free software; you can redistribute it and/or modify |
| 16 | * it under the terms of the GNU General Public License as published by |
| 17 | * the Free Software Foundation; either version 2 of the License, or |
| 18 | * (at your option) any later version. |
| 19 | * |
| 20 | * `Become' is distributed in the hope that it will be useful, |
| 21 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 22 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 23 | * GNU General Public License for more details. |
| 24 | * |
| 25 | * You should have received a copy of the GNU General Public License |
| 26 | * along with `become'; if not, write to the Free Software Foundation, |
| 27 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 28 | */ |
| 29 | |
| 30 | /*----- Revision history --------------------------------------------------* |
| 31 | * |
| 32 | * $Log: idea.h,v $ |
| 33 | * Revision 1.2 1997/08/04 10:24:22 mdw |
| 34 | * Sources placed under CVS control. |
| 35 | * |
| 36 | * Revision 1.1 1997/07/21 13:47:48 mdw |
| 37 | * Initial revision |
| 38 | * |
| 39 | */ |
| 40 | |
| 41 | #ifndef IDEA_H |
| 42 | #define IDEA_H |
| 43 | |
| 44 | #ifdef __cplusplus |
| 45 | extern "C" { |
| 46 | #endif |
| 47 | |
| 48 | /*----- Required headers --------------------------------------------------*/ |
| 49 | |
| 50 | #ifndef CONFIG_H |
| 51 | # include "config.h" |
| 52 | #endif |
| 53 | |
| 54 | /*----- Useful constants --------------------------------------------------*/ |
| 55 | |
| 56 | #define IDEA_BLKSIZE (8u) /* Number of bytes in IDEA block */ |
| 57 | #define IDEA_KEYSIZE (16u) /* Number of bytes in IDEA key */ |
| 58 | #define IDEA_EXPKEYSIZE (52u) /* Number of ints in expanded key */ |
| 59 | |
| 60 | /*----- Type definitions --------------------------------------------------*/ |
| 61 | |
| 62 | typedef struct idea_key { |
| 63 | int k[IDEA_EXPKEYSIZE]; /* Subkey array */ |
| 64 | } idea_key; |
| 65 | |
| 66 | /*----- Functions provided ------------------------------------------------*/ |
| 67 | |
| 68 | /* --- @idea_ekeys@ --- * |
| 69 | * |
| 70 | * Arguments: @idea_key *k@ = the expanded key buffer |
| 71 | * @const unsigned char *key@ = the user's key encryption key |
| 72 | * |
| 73 | * Returns: --- |
| 74 | * |
| 75 | * Use: Unpacks an encryption key. |
| 76 | */ |
| 77 | |
| 78 | extern void idea_ekeys(idea_key */*k*/, const unsigned char */*key*/); |
| 79 | |
| 80 | /* --- @idea_invertKey@ --- * |
| 81 | * |
| 82 | * Arguments: @const idea_key *in@ = pointer to input expanded key buffer |
| 83 | * @idea_key *out@ = pointer to output expanded key buffer |
| 84 | * |
| 85 | * Returns: --- |
| 86 | * |
| 87 | * Use: Computes the inverse (decryption) key given an expanded |
| 88 | * IDEA encryption key. |
| 89 | */ |
| 90 | |
| 91 | extern void idea_invertKey(const idea_key */*in*/, idea_key */*out*/); |
| 92 | |
| 93 | /* --- @idea_dkeys@ --- * |
| 94 | * |
| 95 | * Arguments: @idea_key *k@ = the expanded key buffer |
| 96 | * @const unsigned char *key@ = the user's key encryption key |
| 97 | * |
| 98 | * Returns: --- |
| 99 | * |
| 100 | * Use: Unpacks a decryption key. |
| 101 | */ |
| 102 | |
| 103 | extern void idea_dkeys(idea_key */*k*/, const unsigned char */*key*/); |
| 104 | |
| 105 | /* --- @idea_encrypt@ --- * |
| 106 | * |
| 107 | * Arguments: @const idea_key *k@ = key to use |
| 108 | * @const void *src@ = block to encrypt |
| 109 | * @void *dest@ = where to store the result |
| 110 | * |
| 111 | * |
| 112 | * Returns: --- |
| 113 | * |
| 114 | * Use: Encrypts (or decrypts) a block, using the IDEA cryptosystem. |
| 115 | * Since the decryption operation is the same as encryption |
| 116 | * except that a different key buffer is used, this is all we |
| 117 | * need to complete the simple bits. |
| 118 | */ |
| 119 | |
| 120 | extern void idea_encrypt(const idea_key */*k*/, |
| 121 | const void */*src*/, void */*dest*/); |
| 122 | |
| 123 | /*----- That's all, folks -------------------------------------------------*/ |
| 124 | |
| 125 | #ifdef __cplusplus |
| 126 | } |
| 127 | #endif |
| 128 | |
| 129 | #endif |