rc5_enc.c revision 296341
1/* crypto/rc5/rc5_enc.c */ 2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59#include <stdio.h> 60#include <openssl/rc5.h> 61#include "rc5_locl.h" 62 63void RC5_32_cbc_encrypt(const unsigned char *in, unsigned char *out, 64 long length, RC5_32_KEY *ks, unsigned char *iv, 65 int encrypt) 66{ 67 register unsigned long tin0, tin1; 68 register unsigned long tout0, tout1, xor0, xor1; 69 register long l = length; 70 unsigned long tin[2]; 71 72 if (encrypt) { 73 c2l(iv, tout0); 74 c2l(iv, tout1); 75 iv -= 8; 76 for (l -= 8; l >= 0; l -= 8) { 77 c2l(in, tin0); 78 c2l(in, tin1); 79 tin0 ^= tout0; 80 tin1 ^= tout1; 81 tin[0] = tin0; 82 tin[1] = tin1; 83 RC5_32_encrypt(tin, ks); 84 tout0 = tin[0]; 85 l2c(tout0, out); 86 tout1 = tin[1]; 87 l2c(tout1, out); 88 } 89 if (l != -8) { 90 c2ln(in, tin0, tin1, l + 8); 91 tin0 ^= tout0; 92 tin1 ^= tout1; 93 tin[0] = tin0; 94 tin[1] = tin1; 95 RC5_32_encrypt(tin, ks); 96 tout0 = tin[0]; 97 l2c(tout0, out); 98 tout1 = tin[1]; 99 l2c(tout1, out); 100 } 101 l2c(tout0, iv); 102 l2c(tout1, iv); 103 } else { 104 c2l(iv, xor0); 105 c2l(iv, xor1); 106 iv -= 8; 107 for (l -= 8; l >= 0; l -= 8) { 108 c2l(in, tin0); 109 tin[0] = tin0; 110 c2l(in, tin1); 111 tin[1] = tin1; 112 RC5_32_decrypt(tin, ks); 113 tout0 = tin[0] ^ xor0; 114 tout1 = tin[1] ^ xor1; 115 l2c(tout0, out); 116 l2c(tout1, out); 117 xor0 = tin0; 118 xor1 = tin1; 119 } 120 if (l != -8) { 121 c2l(in, tin0); 122 tin[0] = tin0; 123 c2l(in, tin1); 124 tin[1] = tin1; 125 RC5_32_decrypt(tin, ks); 126 tout0 = tin[0] ^ xor0; 127 tout1 = tin[1] ^ xor1; 128 l2cn(tout0, tout1, out, l + 8); 129 xor0 = tin0; 130 xor1 = tin1; 131 } 132 l2c(xor0, iv); 133 l2c(xor1, iv); 134 } 135 tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0; 136 tin[0] = tin[1] = 0; 137} 138 139void RC5_32_encrypt(unsigned long *d, RC5_32_KEY *key) 140{ 141 RC5_32_INT a, b, *s; 142 143 s = key->data; 144 145 a = d[0] + s[0]; 146 b = d[1] + s[1]; 147 E_RC5_32(a, b, s, 2); 148 E_RC5_32(a, b, s, 4); 149 E_RC5_32(a, b, s, 6); 150 E_RC5_32(a, b, s, 8); 151 E_RC5_32(a, b, s, 10); 152 E_RC5_32(a, b, s, 12); 153 E_RC5_32(a, b, s, 14); 154 E_RC5_32(a, b, s, 16); 155 if (key->rounds == 12) { 156 E_RC5_32(a, b, s, 18); 157 E_RC5_32(a, b, s, 20); 158 E_RC5_32(a, b, s, 22); 159 E_RC5_32(a, b, s, 24); 160 } else if (key->rounds == 16) { 161 /* Do a full expansion to avoid a jump */ 162 E_RC5_32(a, b, s, 18); 163 E_RC5_32(a, b, s, 20); 164 E_RC5_32(a, b, s, 22); 165 E_RC5_32(a, b, s, 24); 166 E_RC5_32(a, b, s, 26); 167 E_RC5_32(a, b, s, 28); 168 E_RC5_32(a, b, s, 30); 169 E_RC5_32(a, b, s, 32); 170 } 171 d[0] = a; 172 d[1] = b; 173} 174 175void RC5_32_decrypt(unsigned long *d, RC5_32_KEY *key) 176{ 177 RC5_32_INT a, b, *s; 178 179 s = key->data; 180 181 a = d[0]; 182 b = d[1]; 183 if (key->rounds == 16) { 184 D_RC5_32(a, b, s, 32); 185 D_RC5_32(a, b, s, 30); 186 D_RC5_32(a, b, s, 28); 187 D_RC5_32(a, b, s, 26); 188 /* Do a full expansion to avoid a jump */ 189 D_RC5_32(a, b, s, 24); 190 D_RC5_32(a, b, s, 22); 191 D_RC5_32(a, b, s, 20); 192 D_RC5_32(a, b, s, 18); 193 } else if (key->rounds == 12) { 194 D_RC5_32(a, b, s, 24); 195 D_RC5_32(a, b, s, 22); 196 D_RC5_32(a, b, s, 20); 197 D_RC5_32(a, b, s, 18); 198 } 199 D_RC5_32(a, b, s, 16); 200 D_RC5_32(a, b, s, 14); 201 D_RC5_32(a, b, s, 12); 202 D_RC5_32(a, b, s, 10); 203 D_RC5_32(a, b, s, 8); 204 D_RC5_32(a, b, s, 6); 205 D_RC5_32(a, b, s, 4); 206 D_RC5_32(a, b, s, 2); 207 d[0] = a - s[0]; 208 d[1] = b - s[1]; 209} 210