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 #ifdef _LIBC
84 extern unsigned long time();
85 extern int write();
86 #endif
87 const unsigned char *buf=_buf;
88 long rnum;
89 int i,j,k,outnum;
90 static unsigned char *outbuf=NULL;
91 unsigned char shortbuf[8];
92 unsigned char *p;
93 const unsigned char *cp;
94 static int start=1;
95
96 if (outbuf == NULL)
97 {
98 outbuf=OPENSSL_malloc(BSIZE+HDRSIZE);
99 if (outbuf == NULL) return(-1);
100 }
101 /* If we are sending less than 8 bytes, the same char will look
102 * the same if we don't pad it out with random bytes */
103 if (start)
104 {
105 start=0;
106 }
107
108 /* lets recurse if we want to send the data in small chunks */
109 if (len > MAXWRITE)
110 {
111 j=0;
112 for (i=0; i<len; i+=k)
113 {
114 k=DES_enc_write(fd,&(buf[i]),
115 ((len-i) > MAXWRITE)?MAXWRITE:(len-i),sched,iv);
116 if (k < 0)
117 return(k);
118 else
119 j+=k;
120 }
121 return(j);
122 }
123
124 /* write length first */
125 p=outbuf;
126 l2n(len,p);
127
128 /* pad short strings */
129 if (len < 8)
130 {
131 cp=shortbuf;
132 memcpy(shortbuf,buf,len);
133 RAND_pseudo_bytes(shortbuf+len, 8-len);
134 rnum=8;
135 }
136 else
137 {
138 cp=buf;
139 rnum=((len+7)/8*8); /* round up to nearest eight */
140 }
141
142 if (DES_rw_mode & DES_PCBC_MODE)
143 DES_pcbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv,
144 DES_ENCRYPT);
145 else
146 DES_cbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv,
147 DES_ENCRYPT);
148
149 /* output */
150 outnum=rnum+HDRSIZE;
151
152 for (j=0; j<outnum; j+=i)
153 {
154 /* eay 26/08/92 I was not doing writing from where we
155 * got up to. */
156 #ifndef _WIN32
157 i=write(fd,(void *)&(outbuf[j]),outnum-j);
158 #else
159 i=_write(fd,(void *)&(outbuf[j]),outnum-j);
160 #endif
161 if (i == -1)
162 {
163 #ifdef EINTR
164 if (errno == EINTR)
165 i=0;
166 else
167 #endif
168 /* This is really a bad error - very bad
169 * It will stuff-up both ends. */
170 return(-1);
171 }
172 }
173
174 return(len);
175 }
176