1 /* crypto/des/enc_writ.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 <errno.h>
  60 #include <time.h>
  61 #include <stdio.h>
  62 #include "cryptlib.h"
  63 #include "des_locl.h"
  64 #include <openssl/rand.h>
  65 
  66 /*
  67  * WARNINGS:
  68  *
  69  *  -  The data format used by DES_enc_write() and DES_enc_read()
  70  *     has a cryptographic weakness: When asked to write more
  71  *     than MAXWRITE bytes, DES_enc_write will split the data
  72  *     into several chunks that are all encrypted
  73  *     using the same IV.  So don't use these functions unless you
  74  *     are sure you know what you do (in which case you might
  75  *     not want to use them anyway).
  76  *
  77  *  -  This code cannot handle non-blocking sockets.
  78  */
  79 
  80 int DES_enc_write(int fd, const void *_buf, int len,
  81                   DES_key_schedule *sched, DES_cblock *iv)
  82         {
  83 #if defined(OPENSSL_NO_POSIX_IO)
  84         return (-1);
  85 #else
  86 #ifdef _LIBC
  87         extern unsigned long time();
  88         extern int write();
  89 #endif
  90         const unsigned char *buf=_buf;
  91         long rnum;
  92         int i,j,k,outnum;
  93         static unsigned char *outbuf=NULL;
  94         unsigned char shortbuf[8];
  95         unsigned char *p;
  96         const unsigned char *cp;
  97         static int start=1;
  98 
  99         if (outbuf == NULL)
 100                 {
 101                 outbuf=OPENSSL_malloc(BSIZE+HDRSIZE);
 102                 if (outbuf == NULL) return(-1);
 103                 }
 104         /* If we are sending less than 8 bytes, the same char will look
 105          * the same if we don't pad it out with random bytes */
 106         if (start)
 107                 {
 108                 start=0;
 109                 }
 110 
 111         /* lets recurse if we want to send the data in small chunks */
 112         if (len > MAXWRITE)
 113                 {
 114                 j=0;
 115                 for (i=0; i<len; i+=k)
 116                         {
 117                         k=DES_enc_write(fd,&(buf[i]),
 118                                 ((len-i) > MAXWRITE)?MAXWRITE:(len-i),sched,iv);
 119                         if (k < 0)
 120                                 return(k);
 121                         else
 122                                 j+=k;
 123                         }
 124                 return(j);
 125                 }
 126 
 127         /* write length first */
 128         p=outbuf;
 129         l2n(len,p);
 130 
 131         /* pad short strings */
 132         if (len < 8)
 133                 {
 134                 cp=shortbuf;
 135                 memcpy(shortbuf,buf,len);
 136                 RAND_pseudo_bytes(shortbuf+len, 8-len);
 137                 rnum=8;
 138                 }
 139         else
 140                 {
 141                 cp=buf;
 142                 rnum=((len+7)/8*8); /* round up to nearest eight */
 143                 }
 144 
 145         if (DES_rw_mode & DES_PCBC_MODE)
 146                 DES_pcbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv,
 147                                  DES_ENCRYPT);
 148         else
 149                 DES_cbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv,
 150                                 DES_ENCRYPT);
 151 
 152         /* output */
 153         outnum=rnum+HDRSIZE;
 154 
 155         for (j=0; j<outnum; j+=i)
 156                 {
 157                 /* eay 26/08/92 I was not doing writing from where we
 158                  * got up to. */
 159 #ifndef _WIN32
 160                 i=write(fd,(void *)&(outbuf[j]),outnum-j);
 161 #else
 162                 i=_write(fd,(void *)&(outbuf[j]),outnum-j);
 163 #endif
 164                 if (i == -1)
 165                         {
 166 #ifdef EINTR
 167                         if (errno == EINTR)
 168                                 i=0;
 169                         else
 170 #endif
 171                                 /* This is really a bad error - very bad
 172                                  * It will stuff-up both ends. */
 173                                 return(-1);
 174                         }
 175                 }
 176 
 177         return(len);
 178 #endif /* OPENSSL_NO_POSIX_IO */
 179         }