rc2_cbc.c revision 68652
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 { 72 c2l(iv,tout0); 73 c2l(iv,tout1); 74 iv-=8; 75 for (l-=8; l>=0; l-=8) 76 { 77 c2l(in,tin0); 78 c2l(in,tin1); 79 tin0^=tout0; 80 tin1^=tout1; 81 tin[0]=tin0; 82 tin[1]=tin1; 83 RC2_encrypt(tin,ks); 84 tout0=tin[0]; l2c(tout0,out); 85 tout1=tin[1]; l2c(tout1,out); 86 } 87 if (l != -8) 88 { 89 c2ln(in,tin0,tin1,l+8); 90 tin0^=tout0; 91 tin1^=tout1; 92 tin[0]=tin0; 93 tin[1]=tin1; 94 RC2_encrypt(tin,ks); 95 tout0=tin[0]; l2c(tout0,out); 96 tout1=tin[1]; l2c(tout1,out); 97 } 98 l2c(tout0,iv); 99 l2c(tout1,iv); 100 } 101 else 102 { 103 c2l(iv,xor0); 104 c2l(iv,xor1); 105 iv-=8; 106 for (l-=8; l>=0; l-=8) 107 { 108 c2l(in,tin0); tin[0]=tin0; 109 c2l(in,tin1); 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 { 120 c2l(in,tin0); tin[0]=tin0; 121 c2l(in,tin1); tin[1]=tin1; 122 RC2_decrypt(tin,ks); 123 tout0=tin[0]^xor0; 124 tout1=tin[1]^xor1; 125 l2cn(tout0,tout1,out,l+8); 126 xor0=tin0; 127 xor1=tin1; 128 } 129 l2c(xor0,iv); 130 l2c(xor1,iv); 131 } 132 tin0=tin1=tout0=tout1=xor0=xor1=0; 133 tin[0]=tin[1]=0; 134 } 135 136void RC2_encrypt(unsigned long *d, RC2_KEY *key) 137 { 138 int i,n; 139 register RC2_INT *p0,*p1; 140 register RC2_INT x0,x1,x2,x3,t; 141 unsigned long l; 142 143 l=d[0]; 144 x0=(RC2_INT)l&0xffff; 145 x1=(RC2_INT)(l>>16L); 146 l=d[1]; 147 x2=(RC2_INT)l&0xffff; 148 x3=(RC2_INT)(l>>16L); 149 150 n=3; 151 i=5; 152 153 p0=p1= &(key->data[0]); 154 for (;;) 155 { 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 { 167 if (--n == 0) 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]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L); 178 d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L); 179 } 180 181void RC2_decrypt(unsigned long *d, RC2_KEY *key) 182 { 183 int i,n; 184 register RC2_INT *p0,*p1; 185 register RC2_INT x0,x1,x2,x3,t; 186 unsigned long l; 187 188 l=d[0]; 189 x0=(RC2_INT)l&0xffff; 190 x1=(RC2_INT)(l>>16L); 191 l=d[1]; 192 x2=(RC2_INT)l&0xffff; 193 x3=(RC2_INT)(l>>16L); 194 195 n=3; 196 i=5; 197 198 p0= &(key->data[63]); 199 p1= &(key->data[0]); 200 for (;;) 201 { 202 t=((x3<<11)|(x3>>5))&0xffff; 203 x3=(t-(x0& ~x2)-(x1&x2)- *(p0--))&0xffff; 204 t=((x2<<13)|(x2>>3))&0xffff; 205 x2=(t-(x3& ~x1)-(x0&x1)- *(p0--))&0xffff; 206 t=((x1<<14)|(x1>>2))&0xffff; 207 x1=(t-(x2& ~x0)-(x3&x0)- *(p0--))&0xffff; 208 t=((x0<<15)|(x0>>1))&0xffff; 209 x0=(t-(x1& ~x3)-(x2&x3)- *(p0--))&0xffff; 210 211 if (--i == 0) 212 { 213 if (--n == 0) break; 214 i=(n == 2)?6:5; 215 216 x3=(x3-p1[x2&0x3f])&0xffff; 217 x2=(x2-p1[x1&0x3f])&0xffff; 218 x1=(x1-p1[x0&0x3f])&0xffff; 219 x0=(x0-p1[x3&0x3f])&0xffff; 220 } 221 } 222 223 d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L); 224 d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L); 225 } 226 227