1 /* crypto/des/ofb64enc.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 /* The input and output encrypted as though 64bit ofb mode is being 62 * used. The extra state information to record how much of the 63 * 64bit block we have used is contained in *num; 64 */ 65 void DES_ofb64_encrypt(register const unsigned char *in, 66 register unsigned char *out, long length, 67 DES_key_schedule *schedule, DES_cblock *ivec, int *num) 68 { 69 register DES_LONG v0,v1,t; 70 register int n= *num; 71 register long l=length; 72 DES_cblock d; 73 register unsigned char *dp; 74 DES_LONG ti[2]; 75 unsigned char *iv; 76 int save=0; 77 78 iv = &(*ivec)[0]; 79 c2l(iv,v0); 80 c2l(iv,v1); 81 ti[0]=v0; 82 ti[1]=v1; 83 dp=d; 84 l2c(v0,dp); 85 l2c(v1,dp); 86 while (l--) 87 { 88 if (n == 0) 89 { 90 DES_encrypt1(ti,schedule,DES_ENCRYPT); 91 dp=d; 92 t=ti[0]; l2c(t,dp); 93 t=ti[1]; l2c(t,dp); 94 save++; 95 } 96 *(out++)= *(in++)^d[n]; 97 n=(n+1)&0x07; 98 } 99 if (save) 100 { 101 v0=ti[0]; 102 v1=ti[1]; 103 iv = &(*ivec)[0]; 104 l2c(v0,iv); 105 l2c(v1,iv); 106 } 107 t=v0=v1=ti[0]=ti[1]=0; 108 *num=n; 109 } 110 111
