1 /* crypto/des/pcbc_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 "des_locl.h" 60 61 void des_pcbc_encrypt(const unsigned char *input, unsigned char *output, 62 long length, des_key_schedule schedule, des_cblock *ivec, int enc) 63 { 64 register DES_LONG sin0,sin1,xor0,xor1,tout0,tout1; 65 DES_LONG tin[2]; 66 const unsigned char *in; 67 unsigned char *out,*iv; 68 69 in=input; 70 out=output; 71 iv = &(*ivec)[0]; 72 73 if (enc) 74 { 75 c2l(iv,xor0); 76 c2l(iv,xor1); 77 for (; length>0; length-=8) 78 { 79 if (length >= 8) 80 { 81 c2l(in,sin0); 82 c2l(in,sin1); 83 } 84 else 85 c2ln(in,sin0,sin1,length); 86 tin[0]=sin0^xor0; 87 tin[1]=sin1^xor1; 88 des_encrypt1((DES_LONG *)tin,schedule,DES_ENCRYPT); 89 tout0=tin[0]; 90 tout1=tin[1]; 91 xor0=sin0^tout0; 92 xor1=sin1^tout1; 93 l2c(tout0,out); 94 l2c(tout1,out); 95 } 96 } 97 else 98 { 99 c2l(iv,xor0); c2l(iv,xor1); 100 for (; length>0; length-=8) 101 { 102 c2l(in,sin0); 103 c2l(in,sin1); 104 tin[0]=sin0; 105 tin[1]=sin1; 106 des_encrypt1((DES_LONG *)tin,schedule,DES_DECRYPT); 107 tout0=tin[0]^xor0; 108 tout1=tin[1]^xor1; 109 if (length >= 8) 110 { 111 l2c(tout0,out); 112 l2c(tout1,out); 113 } 114 else 115 l2cn(tout0,tout1,out,length); 116 xor0=tout0^sin0; 117 xor1=tout1^sin1; 118 } 119 } 120 tin[0]=tin[1]=0; 121 sin0=sin1=xor0=xor1=tout0=tout1=0; 122 } 123