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
80int 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	}
180