Annotation of src/usr.bin/rlogin/des_rw.c, Revision 1.10
1.10 ! millert 1: /* $OpenBSD: des_rw.c,v 1.9 2001/11/19 19:02:16 mpech Exp $ */
1.1 deraadt 2: /* $NetBSD: des_rw.c,v 1.2 1995/03/21 07:58:30 cgd Exp $ */
3:
4: /*-
5: * Copyright (c) 1989, 1993
6: * The Regents of the University of California. All rights reserved.
7: *
8: * Redistribution and use in source and binary forms, with or without
9: * modification, are permitted provided that the following conditions
10: * are met:
11: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
13: * 2. Redistributions in binary form must reproduce the above copyright
14: * notice, this list of conditions and the following disclaimer in the
15: * documentation and/or other materials provided with the distribution.
16: * 3. All advertising materials mentioning features or use of this software
17: * must display the following acknowledgement:
18: * This product includes software developed by the University of
19: * California, Berkeley and its contributors.
20: * 4. Neither the name of the University nor the names of its contributors
21: * may be used to endorse or promote products derived from this software
22: * without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34: * SUCH DAMAGE.
35: */
36:
37: #ifndef lint
38: #if 0
39: static char sccsid[] = "@(#)des_rw.c 8.1 (Berkeley) 6/6/93";
40: #else
1.10 ! millert 41: static char rcsid[] = "$OpenBSD: des_rw.c,v 1.9 2001/11/19 19:02:16 mpech Exp $";
1.1 deraadt 42: #endif
43: #endif /* not lint */
44:
45: #ifdef KERBEROS
46: #include <sys/param.h>
47:
1.7 provos 48: #include <des.h>
1.1 deraadt 49: #include <kerberosIV/krb.h>
50:
51: #include <stdlib.h>
52: #include <string.h>
53: #include <time.h>
54: #include <unistd.h>
1.8 pvalchev 55:
1.10 ! millert 56: void desrw_set_key(des_cblock *, des_key_schedule *);
! 57: void desrw_clear_key(void);
! 58: int des_read(int, char *, int);
! 59: int des_write(int, char *, int);
1.1 deraadt 60:
1.3 tholo 61: static unsigned char des_inbuf[10240], storage[10240], *store_ptr;
1.5 mickey 62: static des_cblock *key;
63: static des_key_schedule *key_schedule;
1.1 deraadt 64:
65: /*
66: * NB: These routines will not function properly if NBIO
67: * is set
68: */
69:
70: /*
71: * des_set_key
72: *
73: * Set des encryption/decryption key for use by the des_read and
74: * des_write routines
75: *
76: * The inkey parameter is actually the DES initial vector,
77: * and the insched is the DES Key unwrapped for faster decryption
78: */
1.3 tholo 79: static int nstored = 0;
1.1 deraadt 80:
1.3 tholo 81: void
82: desrw_set_key(inkey, insched)
1.5 mickey 83: des_cblock *inkey;
84: des_key_schedule*insched;
1.1 deraadt 85: {
86: key = inkey;
1.3 tholo 87: key_schedule = insched;
88: nstored = 0;
1.1 deraadt 89: }
90:
91: void
1.3 tholo 92: desrw_clear_key()
1.1 deraadt 93: {
94: bzero((char *) key, sizeof(C_Block));
95: bzero((char *) key_schedule, sizeof(Key_schedule));
96: }
97:
98:
99: int
100: des_read(fd, buf, len)
101: int fd;
1.9 mpech 102: char *buf;
1.1 deraadt 103: int len;
104: {
1.3 tholo 105: long net_len, rd_len;
1.1 deraadt 106: int nreturned = 0;
107:
108: if (nstored >= len) {
109: (void) bcopy(store_ptr, buf, len);
110: store_ptr += len;
111: nstored -= len;
112: return(len);
113: } else if (nstored) {
114: (void) bcopy(store_ptr, buf, nstored);
115: nreturned += nstored;
116: buf += nstored;
117: len -= nstored;
118: nstored = 0;
119: }
120:
121: if (krb_net_read(fd, (char *)&net_len, sizeof(net_len)) !=
122: sizeof(net_len)) {
123: /* XXX can't read enough, pipe
124: must have closed */
125: return(0);
126: }
127: net_len = ntohl(net_len);
128: if (net_len <= 0 || net_len > sizeof(des_inbuf)) {
129: /* preposterous length; assume out-of-sync; only
130: recourse is to close connection, so return 0 */
131: return(0);
132: }
133: /* the writer tells us how much real data we are getting, but
134: we need to read the pad bytes (8-byte boundary) */
135: rd_len = roundup(net_len, 8);
136: if (krb_net_read(fd, (char *)des_inbuf, rd_len) != rd_len) {
137: /* pipe must have closed, return 0 */
138: return(0);
139: }
1.3 tholo 140: (void) des_pcbc_encrypt((des_cblock *)des_inbuf, /* inbuf */
141: (des_cblock *)storage, /* outbuf */
142: rd_len, /* length */
1.5 mickey 143: *key_schedule, /* DES key */
144: key, /* IV */
1.3 tholo 145: DECRYPT); /* direction */
1.1 deraadt 146:
147: if(net_len < 8)
148: store_ptr = storage + 8 - net_len;
149: else
150: store_ptr = storage;
151:
152: nstored = net_len;
153: if (nstored > len) {
154: (void) bcopy(store_ptr, buf, len);
155: nreturned += len;
156: store_ptr += len;
157: nstored -= len;
158: } else {
159: (void) bcopy(store_ptr, buf, nstored);
160: nreturned += nstored;
161: nstored = 0;
162: }
163:
164: return(nreturned);
165: }
166:
1.3 tholo 167: static unsigned char des_outbuf[10240]; /* > longest write */
1.1 deraadt 168:
169: int
170: des_write(fd, buf, len)
171: int fd;
172: char *buf;
173: int len;
174: {
175: static int seeded = 0;
1.3 tholo 176: static char garbage_buf[8];
1.1 deraadt 177: long net_len, garbage;
178:
179: if(len < 8) {
180: if(!seeded) {
181: seeded = 1;
1.6 dgregor 182: srandom((int) time(NULL));
1.1 deraadt 183: }
184: garbage = random();
185: /* insert random garbage */
186: (void) bcopy(&garbage, garbage_buf, MIN(sizeof(long),8));
187: /* this "right-justifies" the data in the buffer */
188: (void) bcopy(buf, garbage_buf + 8 - len, len);
189: }
190: /* pcbc_encrypt outputs in 8-byte (64 bit) increments */
191:
1.3 tholo 192: (void) des_pcbc_encrypt((des_cblock *)((len < 8) ? garbage_buf : buf),
193: (des_cblock *)des_outbuf,
1.1 deraadt 194: (len < 8) ? 8 : len,
1.5 mickey 195: *key_schedule, /* DES key */
196: key, /* IV */
1.1 deraadt 197: ENCRYPT);
198:
199: /* tell the other end the real amount, but send an 8-byte padded
200: packet */
201: net_len = htonl(len);
202: (void) write(fd, &net_len, sizeof(net_len));
203: (void) write(fd, des_outbuf, roundup(len,8));
204: return(len);
205: }
206: #endif /* KERBEROS */
![[BACK]](/icons/back.gif){kind=icon}
Return to des_rw.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / rlogin