crypto/openssl/crypto/des/enc_writ.c

   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 (len < 0)
 100         return -1;
 101
 102     if (outbuf == NULL) {
 103         outbuf = OPENSSL_malloc(BSIZE + HDRSIZE);
 104         if (outbuf == NULL)
 105             return (-1);
 106     }
 107     /*
 108      * If we are sending less than 8 bytes, the same char will look the same
 109      * if we don't pad it out with random bytes
 110      */
 111     if (start) {
 112         start = 0;
 113     }
 114
 115     /* lets recurse if we want to send the data in small chunks */
 116     if (len > MAXWRITE) {
 117         j = 0;
 118         for (i = 0; i < len; i += k) {
 119             k = DES_enc_write(fd, &(buf[i]),
 120                               ((len - i) > MAXWRITE) ? MAXWRITE : (len - i),
 121                               sched, iv);
 122             if (k < 0)
 123                 return (k);
 124             else
 125                 j += k;
 126         }
 127         return (j);
 128     }
 129
 130     /* write length first */
 131     p = outbuf;
 132     l2n(len, p);
 133
 134     /* pad short strings */
 135     if (len < 8) {
 136         cp = shortbuf;
 137         memcpy(shortbuf, buf, len);
 138         if (RAND_pseudo_bytes(shortbuf + len, 8 - len) < 0) {
 139             return -1;
 140         }
 141         rnum = 8;
 142     } else {
 143         cp = buf;
 144         rnum = ((len + 7) / 8 * 8); /* round up to nearest eight */
 145     }
 146
 147     if (DES_rw_mode & DES_PCBC_MODE)
 148         DES_pcbc_encrypt(cp, &(outbuf[HDRSIZE]), (len < 8) ? 8 : len, sched,
 149                          iv, DES_ENCRYPT);
 150     else
 151         DES_cbc_encrypt(cp, &(outbuf[HDRSIZE]), (len < 8) ? 8 : len, sched,
 152                         iv, DES_ENCRYPT);
 153
 154     /* output */
 155     outnum = rnum + HDRSIZE;
 156
 157     for (j = 0; j < outnum; j += i) {
 158         /*
 159          * eay 26/08/92 I was not doing writing from where we got up to.
 160          */
 161 # ifndef _WIN32
 162         i = write(fd, (void *)&(outbuf[j]), outnum - j);
 163 # else
 164         i = _write(fd, (void *)&(outbuf[j]), outnum - j);
 165 # endif
 166         if (i == -1) {
 167 # ifdef EINTR
 168             if (errno == EINTR)
 169                 i = 0;
 170             else
 171 # endif
 172                 /*
 173                  * This is really a bad error - very bad It will stuff-up
 174                  * both ends.
 175                  */
 176                 return (-1);
 177         }
 178     }
 179
 180     return (len);
 181 #endif                          /* OPENSSL_NO_POSIX_IO */
 182 }