| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Implementation of double- and triple-DES |
| 4 | * |
| 5 | * (c) 1999 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Catacomb. |
| 11 | * |
| 12 | * Catacomb is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * Catacomb is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with Catacomb; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | /*----- Header files ------------------------------------------------------*/ |
| 29 | |
| 30 | #include <assert.h> |
| 31 | #include <stdio.h> |
| 32 | #include <stdlib.h> |
| 33 | #include <string.h> |
| 34 | |
| 35 | #include <mLib/bits.h> |
| 36 | |
| 37 | #include "blkc.h" |
| 38 | #include "des-base.h" |
| 39 | #include "des.h" |
| 40 | #include "des3.h" |
| 41 | #include "gcipher.h" |
| 42 | |
| 43 | /*----- Global variables --------------------------------------------------*/ |
| 44 | |
| 45 | const octet des3_keysz[] = { KSZ_SET, 21, 7, 8, 14, 16, 24, 0 }; |
| 46 | |
| 47 | /*----- Main code ---------------------------------------------------------*/ |
| 48 | |
| 49 | /* --- @des3_init@ --- * |
| 50 | * |
| 51 | * Arguments: @des3_ctx *k@ = pointer to key block |
| 52 | * @const void *buf@ = pointer to key buffer |
| 53 | * @size_t sz@ = size of key material |
| 54 | * |
| 55 | * Returns: --- |
| 56 | * |
| 57 | * Use: Initializes a DES key buffer. The key buffer may have length |
| 58 | * 7, 8, 14, 16, 21, or 24. These correspond to one, two or |
| 59 | * three DES keys, either packed or unpacked (i.e., still |
| 60 | * containing parity bits). |
| 61 | */ |
| 62 | |
| 63 | void des3_init(des3_ctx *k, const void *buf, size_t sz) |
| 64 | { |
| 65 | size_t step; |
| 66 | const octet *p = buf; |
| 67 | |
| 68 | KSZ_ASSERT(des3, sz); |
| 69 | |
| 70 | if (sz % 7 == 0) |
| 71 | step = 7; |
| 72 | else |
| 73 | step = 8; |
| 74 | |
| 75 | des_init(&k->a, p, step); |
| 76 | if (sz > 8) p += step; |
| 77 | des_init(&k->b, p, step); |
| 78 | if (sz > 16) p += step; else p = buf; |
| 79 | des_init(&k->c, p, step); |
| 80 | } |
| 81 | |
| 82 | /* --- @des3_eblk@, @des3_dblk@ --- * |
| 83 | * |
| 84 | * Arguments: @const des3_ctx *k@ = pointer to key block |
| 85 | * @const uint32 s[2]@ = pointer to source block |
| 86 | * @uint32 d[2]@ = pointer to destination block |
| 87 | * |
| 88 | * Returns: --- |
| 89 | * |
| 90 | * Use: Low-level block encryption and decryption. |
| 91 | */ |
| 92 | |
| 93 | void des3_eblk(const des3_ctx *k, const uint32 *s, uint32 *d) |
| 94 | { |
| 95 | uint32 x = s[0], y = s[1]; |
| 96 | DES_IP(x, y); |
| 97 | DES_EBLK(k->a.k, x, y, x, y); |
| 98 | DES_DBLK(k->b.k, x, y, x, y); |
| 99 | DES_EBLK(k->c.k, x, y, x, y); |
| 100 | DES_IPINV(x, y); |
| 101 | d[0] = x, d[1] = y; |
| 102 | } |
| 103 | |
| 104 | void des3_dblk(const des3_ctx *k, const uint32 *s, uint32 *d) |
| 105 | { |
| 106 | uint32 x = s[0], y = s[1]; |
| 107 | DES_IP(x, y); |
| 108 | DES_DBLK(k->c.k, x, y, x, y); |
| 109 | DES_EBLK(k->b.k, x, y, x, y); |
| 110 | DES_DBLK(k->a.k, x, y, x, y); |
| 111 | DES_IPINV(x, y); |
| 112 | d[0] = x, d[1] = y; |
| 113 | } |
| 114 | |
| 115 | BLKC_TEST(DES3, des3) |
| 116 | |
| 117 | /*----- That's all, folks -------------------------------------------------*/ |