1*0Sstevel@tonic-gate /* crypto/des/enc_read.c */
2*0Sstevel@tonic-gate /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3*0Sstevel@tonic-gate * All rights reserved.
4*0Sstevel@tonic-gate *
5*0Sstevel@tonic-gate * This package is an SSL implementation written
6*0Sstevel@tonic-gate * by Eric Young (eay@cryptsoft.com).
7*0Sstevel@tonic-gate * The implementation was written so as to conform with Netscapes SSL.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * This library is free for commercial and non-commercial use as long as
10*0Sstevel@tonic-gate * the following conditions are aheared to. The following conditions
11*0Sstevel@tonic-gate * apply to all code found in this distribution, be it the RC4, RSA,
12*0Sstevel@tonic-gate * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13*0Sstevel@tonic-gate * included with this distribution is covered by the same copyright terms
14*0Sstevel@tonic-gate * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15*0Sstevel@tonic-gate *
16*0Sstevel@tonic-gate * Copyright remains Eric Young's, and as such any Copyright notices in
17*0Sstevel@tonic-gate * the code are not to be removed.
18*0Sstevel@tonic-gate * If this package is used in a product, Eric Young should be given attribution
19*0Sstevel@tonic-gate * as the author of the parts of the library used.
20*0Sstevel@tonic-gate * This can be in the form of a textual message at program startup or
21*0Sstevel@tonic-gate * in documentation (online or textual) provided with the package.
22*0Sstevel@tonic-gate *
23*0Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without
24*0Sstevel@tonic-gate * modification, are permitted provided that the following conditions
25*0Sstevel@tonic-gate * are met:
26*0Sstevel@tonic-gate * 1. Redistributions of source code must retain the copyright
27*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer.
28*0Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright
29*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the
30*0Sstevel@tonic-gate * documentation and/or other materials provided with the distribution.
31*0Sstevel@tonic-gate * 3. All advertising materials mentioning features or use of this software
32*0Sstevel@tonic-gate * must display the following acknowledgement:
33*0Sstevel@tonic-gate * "This product includes cryptographic software written by
34*0Sstevel@tonic-gate * Eric Young (eay@cryptsoft.com)"
35*0Sstevel@tonic-gate * The word 'cryptographic' can be left out if the rouines from the library
36*0Sstevel@tonic-gate * being used are not cryptographic related :-).
37*0Sstevel@tonic-gate * 4. If you include any Windows specific code (or a derivative thereof) from
38*0Sstevel@tonic-gate * the apps directory (application code) you must include an acknowledgement:
39*0Sstevel@tonic-gate * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40*0Sstevel@tonic-gate *
41*0Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42*0Sstevel@tonic-gate * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43*0Sstevel@tonic-gate * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44*0Sstevel@tonic-gate * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45*0Sstevel@tonic-gate * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46*0Sstevel@tonic-gate * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47*0Sstevel@tonic-gate * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48*0Sstevel@tonic-gate * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49*0Sstevel@tonic-gate * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50*0Sstevel@tonic-gate * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51*0Sstevel@tonic-gate * SUCH DAMAGE.
52*0Sstevel@tonic-gate *
53*0Sstevel@tonic-gate * The licence and distribution terms for any publically available version or
54*0Sstevel@tonic-gate * derivative of this code cannot be changed. i.e. this code cannot simply be
55*0Sstevel@tonic-gate * copied and put under another distribution licence
56*0Sstevel@tonic-gate * [including the GNU Public Licence.]
57*0Sstevel@tonic-gate */
58*0Sstevel@tonic-gate
59*0Sstevel@tonic-gate #include <stdio.h>
60*0Sstevel@tonic-gate #include <errno.h>
61*0Sstevel@tonic-gate #include "cryptlib.h"
62*0Sstevel@tonic-gate #include "des_locl.h"
63*0Sstevel@tonic-gate
64*0Sstevel@tonic-gate /* This has some uglies in it but it works - even over sockets. */
65*0Sstevel@tonic-gate /*extern int errno;*/
66*0Sstevel@tonic-gate OPENSSL_IMPLEMENT_GLOBAL(int,DES_rw_mode)=DES_PCBC_MODE;
67*0Sstevel@tonic-gate
68*0Sstevel@tonic-gate
69*0Sstevel@tonic-gate /*
70*0Sstevel@tonic-gate * WARNINGS:
71*0Sstevel@tonic-gate *
72*0Sstevel@tonic-gate * - The data format used by DES_enc_write() and DES_enc_read()
73*0Sstevel@tonic-gate * has a cryptographic weakness: When asked to write more
74*0Sstevel@tonic-gate * than MAXWRITE bytes, DES_enc_write will split the data
75*0Sstevel@tonic-gate * into several chunks that are all encrypted
76*0Sstevel@tonic-gate * using the same IV. So don't use these functions unless you
77*0Sstevel@tonic-gate * are sure you know what you do (in which case you might
78*0Sstevel@tonic-gate * not want to use them anyway).
79*0Sstevel@tonic-gate *
80*0Sstevel@tonic-gate * - This code cannot handle non-blocking sockets.
81*0Sstevel@tonic-gate *
82*0Sstevel@tonic-gate * - This function uses an internal state and thus cannot be
83*0Sstevel@tonic-gate * used on multiple files.
84*0Sstevel@tonic-gate */
85*0Sstevel@tonic-gate
86*0Sstevel@tonic-gate
DES_enc_read(int fd,void * buf,int len,DES_key_schedule * sched,DES_cblock * iv)87*0Sstevel@tonic-gate int DES_enc_read(int fd, void *buf, int len, DES_key_schedule *sched,
88*0Sstevel@tonic-gate DES_cblock *iv)
89*0Sstevel@tonic-gate {
90*0Sstevel@tonic-gate /* data to be unencrypted */
91*0Sstevel@tonic-gate int net_num=0;
92*0Sstevel@tonic-gate static unsigned char *net=NULL;
93*0Sstevel@tonic-gate /* extra unencrypted data
94*0Sstevel@tonic-gate * for when a block of 100 comes in but is des_read one byte at
95*0Sstevel@tonic-gate * a time. */
96*0Sstevel@tonic-gate static unsigned char *unnet=NULL;
97*0Sstevel@tonic-gate static int unnet_start=0;
98*0Sstevel@tonic-gate static int unnet_left=0;
99*0Sstevel@tonic-gate static unsigned char *tmpbuf=NULL;
100*0Sstevel@tonic-gate int i;
101*0Sstevel@tonic-gate long num=0,rnum;
102*0Sstevel@tonic-gate unsigned char *p;
103*0Sstevel@tonic-gate
104*0Sstevel@tonic-gate if (tmpbuf == NULL)
105*0Sstevel@tonic-gate {
106*0Sstevel@tonic-gate tmpbuf=OPENSSL_malloc(BSIZE);
107*0Sstevel@tonic-gate if (tmpbuf == NULL) return(-1);
108*0Sstevel@tonic-gate }
109*0Sstevel@tonic-gate if (net == NULL)
110*0Sstevel@tonic-gate {
111*0Sstevel@tonic-gate net=OPENSSL_malloc(BSIZE);
112*0Sstevel@tonic-gate if (net == NULL) return(-1);
113*0Sstevel@tonic-gate }
114*0Sstevel@tonic-gate if (unnet == NULL)
115*0Sstevel@tonic-gate {
116*0Sstevel@tonic-gate unnet=OPENSSL_malloc(BSIZE);
117*0Sstevel@tonic-gate if (unnet == NULL) return(-1);
118*0Sstevel@tonic-gate }
119*0Sstevel@tonic-gate /* left over data from last decrypt */
120*0Sstevel@tonic-gate if (unnet_left != 0)
121*0Sstevel@tonic-gate {
122*0Sstevel@tonic-gate if (unnet_left < len)
123*0Sstevel@tonic-gate {
124*0Sstevel@tonic-gate /* we still still need more data but will return
125*0Sstevel@tonic-gate * with the number of bytes we have - should always
126*0Sstevel@tonic-gate * check the return value */
127*0Sstevel@tonic-gate memcpy(buf,&(unnet[unnet_start]),
128*0Sstevel@tonic-gate unnet_left);
129*0Sstevel@tonic-gate /* eay 26/08/92 I had the next 2 lines
130*0Sstevel@tonic-gate * reversed :-( */
131*0Sstevel@tonic-gate i=unnet_left;
132*0Sstevel@tonic-gate unnet_start=unnet_left=0;
133*0Sstevel@tonic-gate }
134*0Sstevel@tonic-gate else
135*0Sstevel@tonic-gate {
136*0Sstevel@tonic-gate memcpy(buf,&(unnet[unnet_start]),len);
137*0Sstevel@tonic-gate unnet_start+=len;
138*0Sstevel@tonic-gate unnet_left-=len;
139*0Sstevel@tonic-gate i=len;
140*0Sstevel@tonic-gate }
141*0Sstevel@tonic-gate return(i);
142*0Sstevel@tonic-gate }
143*0Sstevel@tonic-gate
144*0Sstevel@tonic-gate /* We need to get more data. */
145*0Sstevel@tonic-gate if (len > MAXWRITE) len=MAXWRITE;
146*0Sstevel@tonic-gate
147*0Sstevel@tonic-gate /* first - get the length */
148*0Sstevel@tonic-gate while (net_num < HDRSIZE)
149*0Sstevel@tonic-gate {
150*0Sstevel@tonic-gate i=read(fd,(void *)&(net[net_num]),HDRSIZE-net_num);
151*0Sstevel@tonic-gate #ifdef EINTR
152*0Sstevel@tonic-gate if ((i == -1) && (errno == EINTR)) continue;
153*0Sstevel@tonic-gate #endif
154*0Sstevel@tonic-gate if (i <= 0) return(0);
155*0Sstevel@tonic-gate net_num+=i;
156*0Sstevel@tonic-gate }
157*0Sstevel@tonic-gate
158*0Sstevel@tonic-gate /* we now have at net_num bytes in net */
159*0Sstevel@tonic-gate p=net;
160*0Sstevel@tonic-gate /* num=0; */
161*0Sstevel@tonic-gate n2l(p,num);
162*0Sstevel@tonic-gate /* num should be rounded up to the next group of eight
163*0Sstevel@tonic-gate * we make sure that we have read a multiple of 8 bytes from the net.
164*0Sstevel@tonic-gate */
165*0Sstevel@tonic-gate if ((num > MAXWRITE) || (num < 0)) /* error */
166*0Sstevel@tonic-gate return(-1);
167*0Sstevel@tonic-gate rnum=(num < 8)?8:((num+7)/8*8);
168*0Sstevel@tonic-gate
169*0Sstevel@tonic-gate net_num=0;
170*0Sstevel@tonic-gate while (net_num < rnum)
171*0Sstevel@tonic-gate {
172*0Sstevel@tonic-gate i=read(fd,(void *)&(net[net_num]),rnum-net_num);
173*0Sstevel@tonic-gate #ifdef EINTR
174*0Sstevel@tonic-gate if ((i == -1) && (errno == EINTR)) continue;
175*0Sstevel@tonic-gate #endif
176*0Sstevel@tonic-gate if (i <= 0) return(0);
177*0Sstevel@tonic-gate net_num+=i;
178*0Sstevel@tonic-gate }
179*0Sstevel@tonic-gate
180*0Sstevel@tonic-gate /* Check if there will be data left over. */
181*0Sstevel@tonic-gate if (len < num)
182*0Sstevel@tonic-gate {
183*0Sstevel@tonic-gate if (DES_rw_mode & DES_PCBC_MODE)
184*0Sstevel@tonic-gate DES_pcbc_encrypt(net,unnet,num,sched,iv,DES_DECRYPT);
185*0Sstevel@tonic-gate else
186*0Sstevel@tonic-gate DES_cbc_encrypt(net,unnet,num,sched,iv,DES_DECRYPT);
187*0Sstevel@tonic-gate memcpy(buf,unnet,len);
188*0Sstevel@tonic-gate unnet_start=len;
189*0Sstevel@tonic-gate unnet_left=num-len;
190*0Sstevel@tonic-gate
191*0Sstevel@tonic-gate /* The following line is done because we return num
192*0Sstevel@tonic-gate * as the number of bytes read. */
193*0Sstevel@tonic-gate num=len;
194*0Sstevel@tonic-gate }
195*0Sstevel@tonic-gate else
196*0Sstevel@tonic-gate {
197*0Sstevel@tonic-gate /* >output is a multiple of 8 byes, if len < rnum
198*0Sstevel@tonic-gate * >we must be careful. The user must be aware that this
199*0Sstevel@tonic-gate * >routine will write more bytes than he asked for.
200*0Sstevel@tonic-gate * >The length of the buffer must be correct.
201*0Sstevel@tonic-gate * FIXED - Should be ok now 18-9-90 - eay */
202*0Sstevel@tonic-gate if (len < rnum)
203*0Sstevel@tonic-gate {
204*0Sstevel@tonic-gate
205*0Sstevel@tonic-gate if (DES_rw_mode & DES_PCBC_MODE)
206*0Sstevel@tonic-gate DES_pcbc_encrypt(net,tmpbuf,num,sched,iv,
207*0Sstevel@tonic-gate DES_DECRYPT);
208*0Sstevel@tonic-gate else
209*0Sstevel@tonic-gate DES_cbc_encrypt(net,tmpbuf,num,sched,iv,
210*0Sstevel@tonic-gate DES_DECRYPT);
211*0Sstevel@tonic-gate
212*0Sstevel@tonic-gate /* eay 26/08/92 fix a bug that returned more
213*0Sstevel@tonic-gate * bytes than you asked for (returned len bytes :-( */
214*0Sstevel@tonic-gate memcpy(buf,tmpbuf,num);
215*0Sstevel@tonic-gate }
216*0Sstevel@tonic-gate else
217*0Sstevel@tonic-gate {
218*0Sstevel@tonic-gate if (DES_rw_mode & DES_PCBC_MODE)
219*0Sstevel@tonic-gate DES_pcbc_encrypt(net,buf,num,sched,iv,
220*0Sstevel@tonic-gate DES_DECRYPT);
221*0Sstevel@tonic-gate else
222*0Sstevel@tonic-gate DES_cbc_encrypt(net,buf,num,sched,iv,
223*0Sstevel@tonic-gate DES_DECRYPT);
224*0Sstevel@tonic-gate }
225*0Sstevel@tonic-gate }
226*0Sstevel@tonic-gate return num;
227*0Sstevel@tonic-gate }
228*0Sstevel@tonic-gate
229