enc_writ.c revision 68651
155714Skris/* crypto/des/enc_writ.c */ 255714Skris/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 355714Skris * All rights reserved. 455714Skris * 555714Skris * This package is an SSL implementation written 655714Skris * by Eric Young (eay@cryptsoft.com). 755714Skris * The implementation was written so as to conform with Netscapes SSL. 855714Skris * 955714Skris * This library is free for commercial and non-commercial use as long as 1055714Skris * the following conditions are aheared to. The following conditions 1155714Skris * apply to all code found in this distribution, be it the RC4, RSA, 1255714Skris * lhash, DES, etc., code; not just the SSL code. The SSL documentation 1355714Skris * included with this distribution is covered by the same copyright terms 1455714Skris * except that the holder is Tim Hudson (tjh@cryptsoft.com). 1555714Skris * 1655714Skris * Copyright remains Eric Young's, and as such any Copyright notices in 1755714Skris * the code are not to be removed. 1855714Skris * If this package is used in a product, Eric Young should be given attribution 1955714Skris * as the author of the parts of the library used. 2055714Skris * This can be in the form of a textual message at program startup or 2155714Skris * in documentation (online or textual) provided with the package. 2255714Skris * 2355714Skris * Redistribution and use in source and binary forms, with or without 2455714Skris * modification, are permitted provided that the following conditions 2555714Skris * are met: 2655714Skris * 1. Redistributions of source code must retain the copyright 2755714Skris * notice, this list of conditions and the following disclaimer. 2855714Skris * 2. Redistributions in binary form must reproduce the above copyright 2955714Skris * notice, this list of conditions and the following disclaimer in the 3055714Skris * documentation and/or other materials provided with the distribution. 3155714Skris * 3. All advertising materials mentioning features or use of this software 3255714Skris * must display the following acknowledgement: 3355714Skris * "This product includes cryptographic software written by 3455714Skris * Eric Young (eay@cryptsoft.com)" 3555714Skris * The word 'cryptographic' can be left out if the rouines from the library 3655714Skris * being used are not cryptographic related :-). 3755714Skris * 4. If you include any Windows specific code (or a derivative thereof) from 3855714Skris * the apps directory (application code) you must include an acknowledgement: 3955714Skris * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 4055714Skris * 4155714Skris * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 4255714Skris * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 4355714Skris * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 4455714Skris * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 4555714Skris * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 4655714Skris * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 4755714Skris * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 4855714Skris * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 4955714Skris * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 5055714Skris * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 5155714Skris * SUCH DAMAGE. 5255714Skris * 5355714Skris * The licence and distribution terms for any publically available version or 5455714Skris * derivative of this code cannot be changed. i.e. this code cannot simply be 5555714Skris * copied and put under another distribution licence 5655714Skris * [including the GNU Public Licence.] 5755714Skris */ 5855714Skris 5955714Skris#include <errno.h> 6055714Skris#include <time.h> 6155714Skris#include <stdio.h> 6255714Skris#include "cryptlib.h" 6355714Skris#include "des_locl.h" 6455714Skris#include <openssl/rand.h> 6555714Skris 6655714Skris/* 6755714Skris * WARNINGS: 6855714Skris * 6955714Skris * - The data format used by des_enc_write() and des_enc_read() 7055714Skris * has a cryptographic weakness: When asked to write more 7155714Skris * than MAXWRITE bytes, des_enc_write will split the data 7255714Skris * into several chunks that are all encrypted 7355714Skris * using the same IV. So don't use these functions unless you 7455714Skris * are sure you know what you do (in which case you might 7555714Skris * not want to use them anyway). 7655714Skris * 7755714Skris * - This code cannot handle non-blocking sockets. 7855714Skris */ 7955714Skris 8055714Skrisint des_enc_write(int fd, const void *_buf, int len, 8155714Skris des_key_schedule sched, des_cblock *iv) 8255714Skris { 8355714Skris#ifdef _LIBC 8455714Skris extern unsigned long time(); 8555714Skris extern int write(); 8655714Skris#endif 8755714Skris const unsigned char *buf=_buf; 8855714Skris long rnum; 8955714Skris int i,j,k,outnum; 9055714Skris static unsigned char *outbuf=NULL; 9155714Skris unsigned char shortbuf[8]; 9255714Skris unsigned char *p; 9355714Skris const unsigned char *cp; 9455714Skris static int start=1; 9555714Skris 9655714Skris if (outbuf == NULL) 9755714Skris { 9868651Skris outbuf=OPENSSL_malloc(BSIZE+HDRSIZE); 9955714Skris if (outbuf == NULL) return(-1); 10055714Skris } 10155714Skris /* If we are sending less than 8 bytes, the same char will look 10255714Skris * the same if we don't pad it out with random bytes */ 10355714Skris if (start) 10455714Skris { 10555714Skris start=0; 10655714Skris } 10755714Skris 10855714Skris /* lets recurse if we want to send the data in small chunks */ 10955714Skris if (len > MAXWRITE) 11055714Skris { 11155714Skris j=0; 11255714Skris for (i=0; i<len; i+=k) 11355714Skris { 11455714Skris k=des_enc_write(fd,&(buf[i]), 11555714Skris ((len-i) > MAXWRITE)?MAXWRITE:(len-i),sched,iv); 11655714Skris if (k < 0) 11755714Skris return(k); 11855714Skris else 11955714Skris j+=k; 12055714Skris } 12155714Skris return(j); 12255714Skris } 12355714Skris 12455714Skris /* write length first */ 12555714Skris p=outbuf; 12655714Skris l2n(len,p); 12755714Skris 12855714Skris /* pad short strings */ 12955714Skris if (len < 8) 13055714Skris { 13155714Skris cp=shortbuf; 13255714Skris memcpy(shortbuf,buf,len); 13359191Skris RAND_pseudo_bytes(shortbuf+len, 8-len); 13455714Skris rnum=8; 13555714Skris } 13655714Skris else 13755714Skris { 13859191Skris cp=buf; 13955714Skris rnum=((len+7)/8*8); /* round up to nearest eight */ 14055714Skris } 14155714Skris 14255714Skris if (des_rw_mode & DES_PCBC_MODE) 14355714Skris des_pcbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv, 14455714Skris DES_ENCRYPT); 14555714Skris else 14655714Skris des_cbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv, 14755714Skris DES_ENCRYPT); 14855714Skris 14955714Skris /* output */ 15055714Skris outnum=rnum+HDRSIZE; 15155714Skris 15255714Skris for (j=0; j<outnum; j+=i) 15355714Skris { 15455714Skris /* eay 26/08/92 I was not doing writing from where we 15559191Skris * got up to. */ 15659191Skris i=write(fd,(void *)&(outbuf[j]),outnum-j); 15755714Skris if (i == -1) 15855714Skris { 15959191Skris#ifdef EINTR 16055714Skris if (errno == EINTR) 16155714Skris i=0; 16259191Skris else 16359191Skris#endif 16459191Skris /* This is really a bad error - very bad 16555714Skris * It will stuff-up both ends. */ 16655714Skris return(-1); 16755714Skris } 16855714Skris } 16955714Skris 17055714Skris return(len); 17155714Skris } 172