1/* crypto/rc2/rc2_cbc.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 <openssl/rc2.h> 60#include "rc2_locl.h" 61 62void RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long length, 63 RC2_KEY *ks, unsigned char *iv, int encrypt) 64{ 65 register unsigned long tin0, tin1; 66 register unsigned long tout0, tout1, xor0, xor1; 67 register long l = length; 68 unsigned long tin[2]; 69 70 if (encrypt) { 71 c2l(iv, tout0); 72 c2l(iv, tout1); 73 iv -= 8; 74 for (l -= 8; l >= 0; l -= 8) { 75 c2l(in, tin0); 76 c2l(in, tin1); 77 tin0 ^= tout0; 78 tin1 ^= tout1; 79 tin[0] = tin0; 80 tin[1] = tin1; 81 RC2_encrypt(tin, ks); 82 tout0 = tin[0]; 83 l2c(tout0, out); 84 tout1 = tin[1]; 85 l2c(tout1, out); 86 } 87 if (l != -8) { 88 c2ln(in, tin0, tin1, l + 8); 89 tin0 ^= tout0; 90 tin1 ^= tout1; 91 tin[0] = tin0; 92 tin[1] = tin1; 93 RC2_encrypt(tin, ks); 94 tout0 = tin[0]; 95 l2c(tout0, out); 96 tout1 = tin[1]; 97 l2c(tout1, out); 98 } 99 l2c(tout0, iv); 100 l2c(tout1, iv); 101 } else { 102 c2l(iv, xor0); 103 c2l(iv, xor1); 104 iv -= 8; 105 for (l -= 8; l >= 0; l -= 8) { 106 c2l(in, tin0); 107 tin[0] = tin0; 108 c2l(in, tin1); 109 tin[1] = tin1; 110 RC2_decrypt(tin, ks); 111 tout0 = tin[0] ^ xor0; 112 tout1 = tin[1] ^ xor1; 113 l2c(tout0, out); 114 l2c(tout1, out); 115 xor0 = tin0; 116 xor1 = tin1; 117 } 118 if (l != -8) { 119 c2l(in, tin0); 120 tin[0] = tin0; 121 c2l(in, tin1); 122 tin[1] = tin1; 123 RC2_decrypt(tin, ks); 124 tout0 = tin[0] ^ xor0; 125 tout1 = tin[1] ^ xor1; 126 l2cn(tout0, tout1, out, l + 8); 127 xor0 = tin0; 128 xor1 = tin1; 129 } 130 l2c(xor0, iv); 131 l2c(xor1, iv); 132 } 133 tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0; 134 tin[0] = tin[1] = 0; 135} 136 137void RC2_encrypt(unsigned long *d, RC2_KEY *key) 138{ 139 int i, n; 140 register RC2_INT *p0, *p1; 141 register RC2_INT x0, x1, x2, x3, t; 142 unsigned long l; 143 144 l = d[0]; 145 x0 = (RC2_INT) l & 0xffff; 146 x1 = (RC2_INT) (l >> 16L); 147 l = d[1]; 148 x2 = (RC2_INT) l & 0xffff; 149 x3 = (RC2_INT) (l >> 16L); 150 151 n = 3; 152 i = 5; 153 154 p0 = p1 = &(key->data[0]); 155 for (;;) { 156 t = (x0 + (x1 & ~x3) + (x2 & x3) + *(p0++)) & 0xffff; 157 x0 = (t << 1) | (t >> 15); 158 t = (x1 + (x2 & ~x0) + (x3 & x0) + *(p0++)) & 0xffff; 159 x1 = (t << 2) | (t >> 14); 160 t = (x2 + (x3 & ~x1) + (x0 & x1) + *(p0++)) & 0xffff; 161 x2 = (t << 3) | (t >> 13); 162 t = (x3 + (x0 & ~x2) + (x1 & x2) + *(p0++)) & 0xffff; 163 x3 = (t << 5) | (t >> 11); 164 165 if (--i == 0) { 166 if (--n == 0) 167 break; 168 i = (n == 2) ? 6 : 5; 169 170 x0 += p1[x3 & 0x3f]; 171 x1 += p1[x0 & 0x3f]; 172 x2 += p1[x1 & 0x3f]; 173 x3 += p1[x2 & 0x3f]; 174 } 175 } 176 177 d[0] = 178 (unsigned long)(x0 & 0xffff) | ((unsigned long)(x1 & 0xffff) << 16L); 179 d[1] = 180 (unsigned long)(x2 & 0xffff) | ((unsigned long)(x3 & 0xffff) << 16L); 181} 182 183void RC2_decrypt(unsigned long *d, RC2_KEY *key) 184{ 185 int i, n; 186 register RC2_INT *p0, *p1; 187 register RC2_INT x0, x1, x2, x3, t; 188 unsigned long l; 189 190 l = d[0]; 191 x0 = (RC2_INT) l & 0xffff; 192 x1 = (RC2_INT) (l >> 16L); 193 l = d[1]; 194 x2 = (RC2_INT) l & 0xffff; 195 x3 = (RC2_INT) (l >> 16L); 196 197 n = 3; 198 i = 5; 199 200 p0 = &(key->data[63]); 201 p1 = &(key->data[0]); 202 for (;;) { 203 t = ((x3 << 11) | (x3 >> 5)) & 0xffff; 204 x3 = (t - (x0 & ~x2) - (x1 & x2) - *(p0--)) & 0xffff; 205 t = ((x2 << 13) | (x2 >> 3)) & 0xffff; 206 x2 = (t - (x3 & ~x1) - (x0 & x1) - *(p0--)) & 0xffff; 207 t = ((x1 << 14) | (x1 >> 2)) & 0xffff; 208 x1 = (t - (x2 & ~x0) - (x3 & x0) - *(p0--)) & 0xffff; 209 t = ((x0 << 15) | (x0 >> 1)) & 0xffff; 210 x0 = (t - (x1 & ~x3) - (x2 & x3) - *(p0--)) & 0xffff; 211 212 if (--i == 0) { 213 if (--n == 0) 214 break; 215 i = (n == 2) ? 6 : 5; 216 217 x3 = (x3 - p1[x2 & 0x3f]) & 0xffff; 218 x2 = (x2 - p1[x1 & 0x3f]) & 0xffff; 219 x1 = (x1 - p1[x0 & 0x3f]) & 0xffff; 220 x0 = (x0 - p1[x3 & 0x3f]) & 0xffff; 221 } 222 } 223 224 d[0] = 225 (unsigned long)(x0 & 0xffff) | ((unsigned long)(x1 & 0xffff) << 16L); 226 d[1] = 227 (unsigned long)(x2 & 0xffff) | ((unsigned long)(x3 & 0xffff) << 16L); 228} 229