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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 
DES_enc_write(int fd,const void * _buf,int len,DES_key_schedule * sched,DES_cblock * iv)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 	}
180