Ansify some function definitions that were previously overlooked.
[dragonfly.git] / libexec / telnetd / telnetd.c
CommitLineData
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1/*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
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32 *
33 * @(#)telnetd.c 8.4 (Berkeley) 5/30/95
068e7061 34 * $FreeBSD: src/crypto/telnet/telnetd/telnetd.c,v 1.11.2.5 2002/04/13 10:59:09 markm Exp $
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35 */
36
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37#include "telnetd.h"
38#include "pathnames.h"
39
40#include <sys/mman.h>
41#include <err.h>
42#include <libutil.h>
43#include <paths.h>
44#include <termcap.h>
45#include <utmp.h>
46
47#include <arpa/inet.h>
48
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49#ifdef AUTHENTICATION
50#include <libtelnet/auth.h>
51int auth_level = 0;
52#endif
53#ifdef ENCRYPTION
54#include <libtelnet/encrypt.h>
55#endif
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56#include <libtelnet/misc.h>
57
58char remote_hostname[MAXHOSTNAMELEN];
59size_t utmp_len = sizeof(remote_hostname) - 1;
60int registerd_host_only = 0;
61
62
63/*
64 * I/O data buffers,
65 * pointers, and counters.
66 */
67char ptyibuf[BUFSIZ], *ptyip = ptyibuf;
68char ptyibuf2[BUFSIZ];
69
70int readstream(int, char *, int);
71void doit(struct sockaddr *);
72int terminaltypeok(char *);
73
74int hostinfo = 1; /* do we print login banner? */
75
76int debug = 0;
77int keepalive = 1;
78const char *altlogin;
79
80void doit(struct sockaddr *);
81int terminaltypeok(char *);
82void startslave(char *, int, char *);
83extern void usage(void);
84static void _gettermname(void);
85
86/*
87 * The string to pass to getopt(). We do it this way so
88 * that only the actual options that we support will be
89 * passed off to getopt().
90 */
91char valid_opts[] = {
92 'd', ':', 'h', 'k', 'n', 'p', ':', 'S', ':', 'u', ':', 'U',
93 '4', '6',
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94#ifdef AUTHENTICATION
95 'a', ':', 'X', ':',
96#endif
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97#ifdef BFTPDAEMON
98 'B',
99#endif
100#ifdef DIAGNOSTICS
101 'D', ':',
102#endif
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103#ifdef ENCRYPTION
104 'e', ':',
105#endif
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106#ifdef LINEMODE
107 'l',
108#endif
109 '\0'
110};
111
112int family = AF_INET;
113
114#ifndef MAXHOSTNAMELEN
115#define MAXHOSTNAMELEN 256
116#endif /* MAXHOSTNAMELEN */
117
118char *hostname;
119char host_name[MAXHOSTNAMELEN];
120
121extern void telnet(int, int, char *);
122
123int level;
124char user_name[256];
125
126int
127main(int argc, char *argv[])
128{
129 struct sockaddr_storage from;
130 int on = 1, fromlen;
131 int ch;
132#if defined(IPPROTO_IP) && defined(IP_TOS)
133 int tos = -1;
134#endif
135
136 pfrontp = pbackp = ptyobuf;
137 netip = netibuf;
138 nfrontp = nbackp = netobuf;
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139#ifdef ENCRYPTION
140 nclearto = 0;
141#endif /* ENCRYPTION */
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142
143 /*
144 * This initialization causes linemode to default to a configuration
145 * that works on all telnet clients, including the FreeBSD client.
146 * This is not quite the same as the telnet client issuing a "mode
147 * character" command, but has most of the same benefits, and is
148 * preferable since some clients (like usofts) don't have the
149 * mode character command anyway and linemode breaks things.
150 * The most notable symptom of fix is that csh "set filec" operations
151 * like <ESC> (filename completion) and ^D (choices) keys now work
152 * in telnet sessions and can be used more than once on the same line.
153 * CR/LF handling is also corrected in some termio modes. This
154 * change resolves problem reports bin/771 and bin/1037.
155 */
156
157 linemode=1; /*Default to mode that works on bulk of clients*/
158
159 while ((ch = getopt(argc, argv, valid_opts)) != -1) {
160 switch(ch) {
161
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162#ifdef AUTHENTICATION
163 case 'a':
164 /*
165 * Check for required authentication level
166 */
167 if (strcmp(optarg, "debug") == 0) {
168 extern int auth_debug_mode;
169 auth_debug_mode = 1;
170 } else if (strcasecmp(optarg, "none") == 0) {
171 auth_level = 0;
172 } else if (strcasecmp(optarg, "other") == 0) {
173 auth_level = AUTH_OTHER;
174 } else if (strcasecmp(optarg, "user") == 0) {
175 auth_level = AUTH_USER;
176 } else if (strcasecmp(optarg, "valid") == 0) {
177 auth_level = AUTH_VALID;
178 } else if (strcasecmp(optarg, "off") == 0) {
179 /*
180 * This hack turns off authentication
181 */
182 auth_level = -1;
183 } else {
184 warnx("unknown authorization level for -a");
185 }
186 break;
187#endif /* AUTHENTICATION */
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188
189#ifdef BFTPDAEMON
190 case 'B':
191 bftpd++;
192 break;
193#endif /* BFTPDAEMON */
194
195 case 'd':
196 if (strcmp(optarg, "ebug") == 0) {
197 debug++;
198 break;
199 }
200 usage();
201 /* NOTREACHED */
202 break;
203
204#ifdef DIAGNOSTICS
205 case 'D':
206 /*
207 * Check for desired diagnostics capabilities.
208 */
209 if (!strcmp(optarg, "report")) {
210 diagnostic |= TD_REPORT|TD_OPTIONS;
211 } else if (!strcmp(optarg, "exercise")) {
212 diagnostic |= TD_EXERCISE;
213 } else if (!strcmp(optarg, "netdata")) {
214 diagnostic |= TD_NETDATA;
215 } else if (!strcmp(optarg, "ptydata")) {
216 diagnostic |= TD_PTYDATA;
217 } else if (!strcmp(optarg, "options")) {
218 diagnostic |= TD_OPTIONS;
219 } else {
220 usage();
221 /* NOT REACHED */
222 }
223 break;
224#endif /* DIAGNOSTICS */
225
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226#ifdef ENCRYPTION
227 case 'e':
228 if (strcmp(optarg, "debug") == 0) {
229 extern int encrypt_debug_mode;
230 encrypt_debug_mode = 1;
231 break;
232 }
233 usage();
234 /* NOTREACHED */
235 break;
236#endif /* ENCRYPTION */
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237
238 case 'h':
239 hostinfo = 0;
240 break;
241
242#ifdef LINEMODE
243 case 'l':
244 alwayslinemode = 1;
245 break;
246#endif /* LINEMODE */
247
248 case 'k':
249#if defined(LINEMODE) && defined(KLUDGELINEMODE)
250 lmodetype = NO_AUTOKLUDGE;
251#else
252 /* ignore -k option if built without kludge linemode */
253#endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
254 break;
255
256 case 'n':
257 keepalive = 0;
258 break;
259
260 case 'p':
261 altlogin = optarg;
262 break;
263
264 case 'S':
265#ifdef HAS_GETTOS
266 if ((tos = parsetos(optarg, "tcp")) < 0)
267 warnx("%s%s%s",
268 "bad TOS argument '", optarg,
269 "'; will try to use default TOS");
270#else
271 warnx("TOS option unavailable; -S flag not supported");
272#endif
273 break;
274
275 case 'u':
276 utmp_len = (size_t)atoi(optarg);
277 if (utmp_len >= sizeof(remote_hostname))
278 utmp_len = sizeof(remote_hostname) - 1;
279 break;
280
281 case 'U':
282 registerd_host_only = 1;
283 break;
284
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285#ifdef AUTHENTICATION
286 case 'X':
287 /*
288 * Check for invalid authentication types
289 */
290 auth_disable_name(optarg);
291 break;
292#endif /* AUTHENTICATION */
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293
294 case '4':
295 family = AF_INET;
296 break;
297
298#ifdef INET6
299 case '6':
300 family = AF_INET6;
301 break;
302#endif
303
304 default:
305 warnx("%c: unknown option", ch);
306 /* FALLTHROUGH */
307 case '?':
308 usage();
309 /* NOTREACHED */
310 }
311 }
312
313 argc -= optind;
314 argv += optind;
315
316 if (debug) {
317 int s, ns, foo, error;
318 const char *service = "telnet";
319 struct addrinfo hints, *res;
320
321 if (argc > 1) {
322 usage();
323 /* NOT REACHED */
324 } else if (argc == 1)
325 service = *argv;
326
327 memset(&hints, 0, sizeof(hints));
328 hints.ai_flags = AI_PASSIVE;
329 hints.ai_family = family;
330 hints.ai_socktype = SOCK_STREAM;
331 hints.ai_protocol = 0;
332 error = getaddrinfo(NULL, service, &hints, &res);
333
334 if (error) {
335 errx(1, "tcp/%s: %s\n", service, gai_strerror(error));
336 if (error == EAI_SYSTEM)
337 errx(1, "tcp/%s: %s\n", service, strerror(errno));
338 usage();
339 }
340
341 s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
342 if (s < 0)
343 err(1, "socket");
344 (void) setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
345 (char *)&on, sizeof(on));
346 if (bind(s, res->ai_addr, res->ai_addrlen) < 0)
347 err(1, "bind");
348 if (listen(s, 1) < 0)
349 err(1, "listen");
350 foo = res->ai_addrlen;
351 ns = accept(s, res->ai_addr, &foo);
352 if (ns < 0)
353 err(1, "accept");
354 (void) dup2(ns, 0);
355 (void) close(ns);
356 (void) close(s);
357#ifdef convex
358 } else if (argc == 1) {
359 ; /* VOID*/ /* Just ignore the host/port name */
360#endif
361 } else if (argc > 0) {
362 usage();
363 /* NOT REACHED */
364 }
365
366 openlog("telnetd", LOG_PID | LOG_ODELAY, LOG_DAEMON);
367 fromlen = sizeof (from);
368 if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0) {
369 warn("getpeername");
370 _exit(1);
371 }
372 if (keepalive &&
373 setsockopt(0, SOL_SOCKET, SO_KEEPALIVE,
374 (char *)&on, sizeof (on)) < 0) {
375 syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
376 }
377
378#if defined(IPPROTO_IP) && defined(IP_TOS)
379 if (from.ss_family == AF_INET) {
380# if defined(HAS_GETTOS)
381 struct tosent *tp;
382 if (tos < 0 && (tp = gettosbyname("telnet", "tcp")))
383 tos = tp->t_tos;
384# endif
385 if (tos < 0)
386 tos = 020; /* Low Delay bit */
387 if (tos
388 && (setsockopt(0, IPPROTO_IP, IP_TOS,
389 (char *)&tos, sizeof(tos)) < 0)
390 && (errno != ENOPROTOOPT) )
391 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
392 }
393#endif /* defined(IPPROTO_IP) && defined(IP_TOS) */
394 net = 0;
395 doit((struct sockaddr *)&from);
396 /* NOTREACHED */
397 return(0);
398} /* end of main */
399
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400void
401usage(void)
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402{
403 fprintf(stderr, "usage: telnetd");
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404#ifdef AUTHENTICATION
405 fprintf(stderr, " [-a (debug|other|user|valid|off|none)]\n\t");
406#endif
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407#ifdef BFTPDAEMON
408 fprintf(stderr, " [-B]");
409#endif
410 fprintf(stderr, " [-debug]");
411#ifdef DIAGNOSTICS
412 fprintf(stderr, " [-D (options|report|exercise|netdata|ptydata)]\n\t");
413#endif
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414#ifdef AUTHENTICATION
415 fprintf(stderr, " [-edebug]");
416#endif
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417 fprintf(stderr, " [-h]");
418#if defined(LINEMODE) && defined(KLUDGELINEMODE)
419 fprintf(stderr, " [-k]");
420#endif
421#ifdef LINEMODE
422 fprintf(stderr, " [-l]");
423#endif
424 fprintf(stderr, " [-n]");
425 fprintf(stderr, "\n\t");
426#ifdef HAS_GETTOS
427 fprintf(stderr, " [-S tos]");
428#endif
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429#ifdef AUTHENTICATION
430 fprintf(stderr, " [-X auth-type]");
431#endif
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432 fprintf(stderr, " [-u utmp_hostname_length] [-U]");
433 fprintf(stderr, " [port]\n");
434 exit(1);
435}
436
437/*
438 * getterminaltype
439 *
440 * Ask the other end to send along its terminal type and speed.
441 * Output is the variable terminaltype filled in.
442 */
443static unsigned char ttytype_sbbuf[] = {
444 IAC, SB, TELOPT_TTYPE, TELQUAL_SEND, IAC, SE
445};
446
447
068e7061 448#ifndef AUTHENTICATION
984263bc 449#define undef2 __unused
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450#else
451#define undef2
452#endif
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453
454static int
455getterminaltype(char *name undef2)
456{
457 int retval = -1;
458
459 settimer(baseline);
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460#ifdef AUTHENTICATION
461 /*
462 * Handle the Authentication option before we do anything else.
463 */
464 send_do(TELOPT_AUTHENTICATION, 1);
465 while (his_will_wont_is_changing(TELOPT_AUTHENTICATION))
466 ttloop();
467 if (his_state_is_will(TELOPT_AUTHENTICATION)) {
468 retval = auth_wait(name);
469 }
470#endif
984263bc 471
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472#ifdef ENCRYPTION
473 send_will(TELOPT_ENCRYPT, 1);
474#endif /* ENCRYPTION */
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475 send_do(TELOPT_TTYPE, 1);
476 send_do(TELOPT_TSPEED, 1);
477 send_do(TELOPT_XDISPLOC, 1);
478 send_do(TELOPT_NEW_ENVIRON, 1);
479 send_do(TELOPT_OLD_ENVIRON, 1);
480 while (
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481#ifdef ENCRYPTION
482 his_do_dont_is_changing(TELOPT_ENCRYPT) ||
483#endif /* ENCRYPTION */
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484 his_will_wont_is_changing(TELOPT_TTYPE) ||
485 his_will_wont_is_changing(TELOPT_TSPEED) ||
486 his_will_wont_is_changing(TELOPT_XDISPLOC) ||
487 his_will_wont_is_changing(TELOPT_NEW_ENVIRON) ||
488 his_will_wont_is_changing(TELOPT_OLD_ENVIRON)) {
489 ttloop();
490 }
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491#ifdef ENCRYPTION
492 /*
493 * Wait for the negotiation of what type of encryption we can
494 * send with. If autoencrypt is not set, this will just return.
495 */
496 if (his_state_is_will(TELOPT_ENCRYPT)) {
497 encrypt_wait();
498 }
499#endif /* ENCRYPTION */
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500 if (his_state_is_will(TELOPT_TSPEED)) {
501 static unsigned char sb[] =
502 { IAC, SB, TELOPT_TSPEED, TELQUAL_SEND, IAC, SE };
503
504 output_datalen(sb, sizeof sb);
505 DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
506 }
507 if (his_state_is_will(TELOPT_XDISPLOC)) {
508 static unsigned char sb[] =
509 { IAC, SB, TELOPT_XDISPLOC, TELQUAL_SEND, IAC, SE };
510
511 output_datalen(sb, sizeof sb);
512 DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
513 }
514 if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
515 static unsigned char sb[] =
516 { IAC, SB, TELOPT_NEW_ENVIRON, TELQUAL_SEND, IAC, SE };
517
518 output_datalen(sb, sizeof sb);
519 DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
520 }
521 else if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
522 static unsigned char sb[] =
523 { IAC, SB, TELOPT_OLD_ENVIRON, TELQUAL_SEND, IAC, SE };
524
525 output_datalen(sb, sizeof sb);
526 DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
527 }
528 if (his_state_is_will(TELOPT_TTYPE)) {
529
530 output_datalen(ttytype_sbbuf, sizeof ttytype_sbbuf);
531 DIAG(TD_OPTIONS, printsub('>', ttytype_sbbuf + 2,
532 sizeof ttytype_sbbuf - 2););
533 }
534 if (his_state_is_will(TELOPT_TSPEED)) {
535 while (sequenceIs(tspeedsubopt, baseline))
536 ttloop();
537 }
538 if (his_state_is_will(TELOPT_XDISPLOC)) {
539 while (sequenceIs(xdisplocsubopt, baseline))
540 ttloop();
541 }
542 if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
543 while (sequenceIs(environsubopt, baseline))
544 ttloop();
545 }
546 if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
547 while (sequenceIs(oenvironsubopt, baseline))
548 ttloop();
549 }
550 if (his_state_is_will(TELOPT_TTYPE)) {
551 char first[256], last[256];
552
553 while (sequenceIs(ttypesubopt, baseline))
554 ttloop();
555
556 /*
557 * If the other side has already disabled the option, then
558 * we have to just go with what we (might) have already gotten.
559 */
560 if (his_state_is_will(TELOPT_TTYPE) && !terminaltypeok(terminaltype)) {
561 (void) strncpy(first, terminaltype, sizeof(first)-1);
562 first[sizeof(first)-1] = '\0';
563 for(;;) {
564 /*
565 * Save the unknown name, and request the next name.
566 */
567 (void) strncpy(last, terminaltype, sizeof(last)-1);
568 last[sizeof(last)-1] = '\0';
569 _gettermname();
570 if (terminaltypeok(terminaltype))
571 break;
572 if ((strncmp(last, terminaltype, sizeof(last)) == 0) ||
573 his_state_is_wont(TELOPT_TTYPE)) {
574 /*
575 * We've hit the end. If this is the same as
576 * the first name, just go with it.
577 */
578 if (strncmp(first, terminaltype, sizeof(first)) == 0)
579 break;
580 /*
581 * Get the terminal name one more time, so that
582 * RFC1091 compliant telnets will cycle back to
583 * the start of the list.
584 */
585 _gettermname();
586 if (strncmp(first, terminaltype, sizeof(first)) != 0) {
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587 (void) strncpy(terminaltype, first, TERMINAL_TYPE_SIZE-1);
588 terminaltype[TERMINAL_TYPE_SIZE-1] = '\0';
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589 }
590 break;
591 }
592 }
593 }
594 }
595 return(retval);
596} /* end of getterminaltype */
597
598static void
599_gettermname(void)
600{
601 /*
602 * If the client turned off the option,
603 * we can't send another request, so we
604 * just return.
605 */
606 if (his_state_is_wont(TELOPT_TTYPE))
607 return;
608 settimer(baseline);
609 output_datalen(ttytype_sbbuf, sizeof ttytype_sbbuf);
610 DIAG(TD_OPTIONS, printsub('>', ttytype_sbbuf + 2,
611 sizeof ttytype_sbbuf - 2););
612 while (sequenceIs(ttypesubopt, baseline))
613 ttloop();
614}
615
616int
617terminaltypeok(char *s)
618{
619 char buf[1024];
620
621 if (terminaltype == NULL)
622 return(1);
623
624 /*
625 * tgetent() will return 1 if the type is known, and
626 * 0 if it is not known. If it returns -1, it couldn't
627 * open the database. But if we can't open the database,
628 * it won't help to say we failed, because we won't be
629 * able to verify anything else. So, we treat -1 like 1.
630 */
631 if (tgetent(buf, s) == 0)
632 return(0);
633 return(1);
634}
635
636/*
637 * Get a pty, scan input lines.
638 */
639void
640doit(struct sockaddr *who)
641{
642 int err_; /* XXX */
643 int ptynum;
644
645 /*
646 * Find an available pty to use.
647 */
648#ifndef convex
649 pty = getpty(&ptynum);
650 if (pty < 0)
651 fatal(net, "All network ports in use");
652#else
653 for (;;) {
654 char *lp;
655
656 if ((lp = getpty()) == NULL)
657 fatal(net, "Out of ptys");
658
659 if ((pty = open(lp, 2)) >= 0) {
660 strlcpy(line,lp,sizeof(line));
661 line[5] = 't';
662 break;
663 }
664 }
665#endif
666
667 /* get name of connected client */
668 if (realhostname_sa(remote_hostname, sizeof(remote_hostname) - 1,
669 who, who->sa_len) == HOSTNAME_INVALIDADDR && registerd_host_only)
670 fatal(net, "Couldn't resolve your address into a host name.\r\n\
671 Please contact your net administrator");
672 remote_hostname[sizeof(remote_hostname) - 1] = '\0';
673
674 trimdomain(remote_hostname, UT_HOSTSIZE);
675 if (!isdigit(remote_hostname[0]) && strlen(remote_hostname) > utmp_len)
676 err_ = getnameinfo(who, who->sa_len, remote_hostname,
677 sizeof(remote_hostname), NULL, 0,
678 NI_NUMERICHOST|NI_WITHSCOPEID);
679 /* XXX: do 'err_' check */
680
681 (void) gethostname(host_name, sizeof(host_name) - 1);
682 host_name[sizeof(host_name) - 1] = '\0';
683 hostname = host_name;
684
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685#ifdef AUTHENTICATION
686#ifdef ENCRYPTION
687/* The above #ifdefs should actually be "or"'ed, not "and"'ed.
688 * This is a byproduct of needing "#ifdef" and not "#if defined()"
689 * for unifdef. XXX MarkM
690 */
691 auth_encrypt_init(hostname, remote_hostname, "TELNETD", 1);
692#endif
693#endif
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694
695 init_env();
696 /*
697 * get terminal type.
698 */
699 *user_name = 0;
700 level = getterminaltype(user_name);
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701 if (setenv("TERM", terminaltype ? terminaltype : "network", 1) == -1)
702 syslog(LOG_ERR, "setenv: cannot set TERM=%s: %m", terminaltype ? terminaltype : "network");
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703
704 telnet(net, pty, remote_hostname); /* begin server process */
705
706 /*NOTREACHED*/
707} /* end of doit */
708
709/*
710 * Main loop. Select from pty and network, and
711 * hand data to telnet receiver finite state machine.
712 */
713void
714telnet(int f, int p, char *host)
715{
716 int on = 1;
717#define TABBUFSIZ 512
718 char defent[TABBUFSIZ];
719 char defstrs[TABBUFSIZ];
720#undef TABBUFSIZ
721 char *HE;
722 char *HN;
723 char *IM;
724 int nfd;
725
726 /*
727 * Initialize the slc mapping table.
728 */
729 get_slc_defaults();
730
731 /*
732 * Do some tests where it is desireable to wait for a response.
733 * Rather than doing them slowly, one at a time, do them all
734 * at once.
735 */
736 if (my_state_is_wont(TELOPT_SGA))
737 send_will(TELOPT_SGA, 1);
738 /*
739 * Is the client side a 4.2 (NOT 4.3) system? We need to know this
740 * because 4.2 clients are unable to deal with TCP urgent data.
741 *
742 * To find out, we send out a "DO ECHO". If the remote system
743 * answers "WILL ECHO" it is probably a 4.2 client, and we note
744 * that fact ("WILL ECHO" ==> that the client will echo what
745 * WE, the server, sends it; it does NOT mean that the client will
746 * echo the terminal input).
747 */
748 send_do(TELOPT_ECHO, 1);
749
750#ifdef LINEMODE
751 if (his_state_is_wont(TELOPT_LINEMODE)) {
752 /* Query the peer for linemode support by trying to negotiate
753 * the linemode option.
754 */
755 linemode = 0;
756 editmode = 0;
757 send_do(TELOPT_LINEMODE, 1); /* send do linemode */
758 }
759#endif /* LINEMODE */
760
761 /*
762 * Send along a couple of other options that we wish to negotiate.
763 */
764 send_do(TELOPT_NAWS, 1);
765 send_will(TELOPT_STATUS, 1);
766 flowmode = 1; /* default flow control state */
767 restartany = -1; /* uninitialized... */
768 send_do(TELOPT_LFLOW, 1);
769
770 /*
771 * Spin, waiting for a response from the DO ECHO. However,
772 * some REALLY DUMB telnets out there might not respond
773 * to the DO ECHO. So, we spin looking for NAWS, (most dumb
774 * telnets so far seem to respond with WONT for a DO that
775 * they don't understand...) because by the time we get the
776 * response, it will already have processed the DO ECHO.
777 * Kludge upon kludge.
778 */
779 while (his_will_wont_is_changing(TELOPT_NAWS))
780 ttloop();
781
782 /*
783 * But...
784 * The client might have sent a WILL NAWS as part of its
785 * startup code; if so, we'll be here before we get the
786 * response to the DO ECHO. We'll make the assumption
787 * that any implementation that understands about NAWS
788 * is a modern enough implementation that it will respond
789 * to our DO ECHO request; hence we'll do another spin
790 * waiting for the ECHO option to settle down, which is
791 * what we wanted to do in the first place...
792 */
793 if (his_want_state_is_will(TELOPT_ECHO) &&
794 his_state_is_will(TELOPT_NAWS)) {
795 while (his_will_wont_is_changing(TELOPT_ECHO))
796 ttloop();
797 }
798 /*
799 * On the off chance that the telnet client is broken and does not
800 * respond to the DO ECHO we sent, (after all, we did send the
801 * DO NAWS negotiation after the DO ECHO, and we won't get here
802 * until a response to the DO NAWS comes back) simulate the
803 * receipt of a will echo. This will also send a WONT ECHO
804 * to the client, since we assume that the client failed to
805 * respond because it believes that it is already in DO ECHO
806 * mode, which we do not want.
807 */
808 if (his_want_state_is_will(TELOPT_ECHO)) {
809 DIAG(TD_OPTIONS, output_data("td: simulating recv\r\n"));
810 willoption(TELOPT_ECHO);
811 }
812
813 /*
814 * Finally, to clean things up, we turn on our echo. This
815 * will break stupid 4.2 telnets out of local terminal echo.
816 */
817
818 if (my_state_is_wont(TELOPT_ECHO))
819 send_will(TELOPT_ECHO, 1);
820
821 /*
822 * Turn on packet mode
823 */
824 (void) ioctl(p, TIOCPKT, (char *)&on);
825
826#if defined(LINEMODE) && defined(KLUDGELINEMODE)
827 /*
828 * Continuing line mode support. If client does not support
829 * real linemode, attempt to negotiate kludge linemode by sending
830 * the do timing mark sequence.
831 */
832 if (lmodetype < REAL_LINEMODE)
833 send_do(TELOPT_TM, 1);
834#endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
835
836 /*
837 * Call telrcv() once to pick up anything received during
838 * terminal type negotiation, 4.2/4.3 determination, and
839 * linemode negotiation.
840 */
841 telrcv();
842
843 (void) ioctl(f, FIONBIO, (char *)&on);
844 (void) ioctl(p, FIONBIO, (char *)&on);
845
846#if defined(SO_OOBINLINE)
847 (void) setsockopt(net, SOL_SOCKET, SO_OOBINLINE,
848 (char *)&on, sizeof on);
849#endif /* defined(SO_OOBINLINE) */
850
851#ifdef SIGTSTP
852 (void) signal(SIGTSTP, SIG_IGN);
853#endif
854#ifdef SIGTTOU
855 /*
856 * Ignoring SIGTTOU keeps the kernel from blocking us
857 * in ttioct() in /sys/tty.c.
858 */
859 (void) signal(SIGTTOU, SIG_IGN);
860#endif
861
862 (void) signal(SIGCHLD, cleanup);
863
864#ifdef TIOCNOTTY
865 {
866 int t;
867 t = open(_PATH_TTY, O_RDWR);
868 if (t >= 0) {
60233e58 869 (void) ioctl(t, TIOCNOTTY, NULL);
984263bc
MD
870 (void) close(t);
871 }
872 }
873#endif
874
875 /*
876 * Show banner that getty never gave.
877 *
878 * We put the banner in the pty input buffer. This way, it
879 * gets carriage return null processing, etc., just like all
880 * other pty --> client data.
881 */
882
883 if (getent(defent, "default") == 1) {
884 char *cp=defstrs;
885
886 HE = Getstr("he", &cp);
887 HN = Getstr("hn", &cp);
888 IM = Getstr("im", &cp);
889 if (HN && *HN)
890 (void) strlcpy(host_name, HN, sizeof(host_name));
678e8cc6 891 if (IM == NULL)
984263bc
MD
892 IM = strdup("");
893 } else {
894 IM = strdup(DEFAULT_IM);
678e8cc6 895 HE = NULL;
984263bc
MD
896 }
897 edithost(HE, host_name);
898 if (hostinfo && *IM)
899 putf(IM, ptyibuf2);
900
901 if (pcc)
902 (void) strncat(ptyibuf2, ptyip, pcc+1);
903 ptyip = ptyibuf2;
904 pcc = strlen(ptyip);
905#ifdef LINEMODE
906 /*
907 * Last check to make sure all our states are correct.
908 */
909 init_termbuf();
910 localstat();
911#endif /* LINEMODE */
912
913 DIAG(TD_REPORT, output_data("td: Entering processing loop\r\n"));
914
915 /*
916 * Startup the login process on the slave side of the terminal
917 * now. We delay this until here to insure option negotiation
918 * is complete.
919 */
920 startslave(host, level, user_name);
921
922 nfd = ((f > p) ? f : p) + 1;
923 for (;;) {
924 fd_set ibits, obits, xbits;
925 int c;
926
927 if (ncc < 0 && pcc < 0)
928 break;
929
930 FD_ZERO(&ibits);
931 FD_ZERO(&obits);
932 FD_ZERO(&xbits);
933 /*
934 * Never look for input if there's still
935 * stuff in the corresponding output buffer
936 */
937 if (nfrontp - nbackp || pcc > 0) {
938 FD_SET(f, &obits);
939 } else {
940 FD_SET(p, &ibits);
941 }
942 if (pfrontp - pbackp || ncc > 0) {
943 FD_SET(p, &obits);
944 } else {
945 FD_SET(f, &ibits);
946 }
947 if (!SYNCHing) {
948 FD_SET(f, &xbits);
949 }
60233e58 950 if ((c = select(nfd, &ibits, &obits, &xbits, NULL)) < 1) {
984263bc
MD
951 if (c == -1) {
952 if (errno == EINTR) {
953 continue;
954 }
955 }
956 sleep(5);
957 continue;
958 }
959
960 /*
961 * Any urgent data?
962 */
963 if (FD_ISSET(net, &xbits)) {
964 SYNCHing = 1;
965 }
966
967 /*
968 * Something to read from the network...
969 */
970 if (FD_ISSET(net, &ibits)) {
971#if !defined(SO_OOBINLINE)
972 /*
973 * In 4.2 (and 4.3 beta) systems, the
974 * OOB indication and data handling in the kernel
975 * is such that if two separate TCP Urgent requests
976 * come in, one byte of TCP data will be overlaid.
977 * This is fatal for Telnet, but we try to live
978 * with it.
979 *
980 * In addition, in 4.2 (and...), a special protocol
981 * is needed to pick up the TCP Urgent data in
982 * the correct sequence.
983 *
984 * What we do is: if we think we are in urgent
985 * mode, we look to see if we are "at the mark".
986 * If we are, we do an OOB receive. If we run
987 * this twice, we will do the OOB receive twice,
988 * but the second will fail, since the second
989 * time we were "at the mark", but there wasn't
990 * any data there (the kernel doesn't reset
991 * "at the mark" until we do a normal read).
992 * Once we've read the OOB data, we go ahead
993 * and do normal reads.
994 *
995 * There is also another problem, which is that
996 * since the OOB byte we read doesn't put us
997 * out of OOB state, and since that byte is most
998 * likely the TELNET DM (data mark), we would
999 * stay in the TELNET SYNCH (SYNCHing) state.
1000 * So, clocks to the rescue. If we've "just"
1001 * received a DM, then we test for the
1002 * presence of OOB data when the receive OOB
1003 * fails (and AFTER we did the normal mode read
1004 * to clear "at the mark").
1005 */
1006 if (SYNCHing) {
1007 int atmark;
1008
1009 (void) ioctl(net, SIOCATMARK, (char *)&atmark);
1010 if (atmark) {
1011 ncc = recv(net, netibuf, sizeof (netibuf), MSG_OOB);
1012 if ((ncc == -1) && (errno == EINVAL)) {
1013 ncc = read(net, netibuf, sizeof (netibuf));
1014 if (sequenceIs(didnetreceive, gotDM)) {
1015 SYNCHing = stilloob(net);
1016 }
1017 }
1018 } else {
1019 ncc = read(net, netibuf, sizeof (netibuf));
1020 }
1021 } else {
1022 ncc = read(net, netibuf, sizeof (netibuf));
1023 }
1024 settimer(didnetreceive);
1025#else /* !defined(SO_OOBINLINE)) */
1026 ncc = read(net, netibuf, sizeof (netibuf));
1027#endif /* !defined(SO_OOBINLINE)) */
1028 if (ncc < 0 && errno == EWOULDBLOCK)
1029 ncc = 0;
1030 else {
1031 if (ncc <= 0) {
1032 break;
1033 }
1034 netip = netibuf;
1035 }
1036 DIAG((TD_REPORT | TD_NETDATA),
1037 output_data("td: netread %d chars\r\n", ncc));
1038 DIAG(TD_NETDATA, printdata("nd", netip, ncc));
1039 }
1040
1041 /*
1042 * Something to read from the pty...
1043 */
1044 if (FD_ISSET(p, &ibits)) {
1045 pcc = read(p, ptyibuf, BUFSIZ);
1046 /*
1047 * On some systems, if we try to read something
1048 * off the master side before the slave side is
1049 * opened, we get EIO.
1050 */
1051 if (pcc < 0 && (errno == EWOULDBLOCK ||
1052#ifdef EAGAIN
1053 errno == EAGAIN ||
1054#endif
1055 errno == EIO)) {
1056 pcc = 0;
1057 } else {
1058 if (pcc <= 0)
1059 break;
1060#ifdef LINEMODE
1061 /*
1062 * If ioctl from pty, pass it through net
1063 */
1064 if (ptyibuf[0] & TIOCPKT_IOCTL) {
1065 copy_termbuf(ptyibuf+1, pcc-1);
1066 localstat();
1067 pcc = 1;
1068 }
1069#endif /* LINEMODE */
1070 if (ptyibuf[0] & TIOCPKT_FLUSHWRITE) {
1071 netclear(); /* clear buffer back */
1072#ifndef NO_URGENT
1073 /*
1074 * There are client telnets on some
1075 * operating systems get screwed up
1076 * royally if we send them urgent
1077 * mode data.
1078 */
1079 output_data("%c%c", IAC, DM);
1080 neturg = nfrontp-1; /* off by one XXX */
1081 DIAG(TD_OPTIONS,
1082 printoption("td: send IAC", DM));
1083
1084#endif
1085 }
1086 if (his_state_is_will(TELOPT_LFLOW) &&
1087 (ptyibuf[0] &
1088 (TIOCPKT_NOSTOP|TIOCPKT_DOSTOP))) {
1089 int newflow =
1090 ptyibuf[0] & TIOCPKT_DOSTOP ? 1 : 0;
1091 if (newflow != flowmode) {
1092 flowmode = newflow;
1093 output_data("%c%c%c%c%c%c",
1094 IAC, SB, TELOPT_LFLOW,
1095 flowmode ? LFLOW_ON
1096 : LFLOW_OFF,
1097 IAC, SE);
1098 DIAG(TD_OPTIONS, printsub('>',
1099 (unsigned char *)nfrontp-4,
1100 4););
1101 }
1102 }
1103 pcc--;
1104 ptyip = ptyibuf+1;
1105 }
1106 }
1107
1108 while (pcc > 0) {
1109 if ((&netobuf[BUFSIZ] - nfrontp) < 2)
1110 break;
1111 c = *ptyip++ & 0377, pcc--;
1112 if (c == IAC)
1113 output_data("%c", c);
1114 output_data("%c", c);
1115 if ((c == '\r') && (my_state_is_wont(TELOPT_BINARY))) {
1116 if (pcc > 0 && ((*ptyip & 0377) == '\n')) {
1117 output_data("%c", *ptyip++ & 0377);
1118 pcc--;
1119 } else
1120 output_data("%c", '\0');
1121 }
1122 }
1123
1124 if (FD_ISSET(f, &obits) && (nfrontp - nbackp) > 0)
1125 netflush();
1126 if (ncc > 0)
1127 telrcv();
1128 if (FD_ISSET(p, &obits) && (pfrontp - pbackp) > 0)
1129 ptyflush();
1130 }
1131 cleanup(0);
1132} /* end of telnet */
1133
1134#ifndef TCSIG
1135# ifdef TIOCSIG
1136# define TCSIG TIOCSIG
1137# endif
1138#endif
1139
1140/*
1141 * Send interrupt to process on other side of pty.
1142 * If it is in raw mode, just write NULL;
1143 * otherwise, write intr char.
1144 */
1145void
1146interrupt(void)
1147{
1148 ptyflush(); /* half-hearted */
1149
1150#ifdef TCSIG
1151 (void) ioctl(pty, TCSIG, (char *)SIGINT);
1152#else /* TCSIG */
1153 init_termbuf();
1154 *pfrontp++ = slctab[SLC_IP].sptr ?
1155 (unsigned char)*slctab[SLC_IP].sptr : '\177';
1156#endif /* TCSIG */
1157}
1158
1159/*
1160 * Send quit to process on other side of pty.
1161 * If it is in raw mode, just write NULL;
1162 * otherwise, write quit char.
1163 */
1164void
1165sendbrk(void)
1166{
1167 ptyflush(); /* half-hearted */
1168#ifdef TCSIG
1169 (void) ioctl(pty, TCSIG, (char *)SIGQUIT);
1170#else /* TCSIG */
1171 init_termbuf();
1172 *pfrontp++ = slctab[SLC_ABORT].sptr ?
1173 (unsigned char)*slctab[SLC_ABORT].sptr : '\034';
1174#endif /* TCSIG */
1175}
1176
1177void
1178sendsusp(void)
1179{
1180#ifdef SIGTSTP
1181 ptyflush(); /* half-hearted */
1182# ifdef TCSIG
1183 (void) ioctl(pty, TCSIG, (char *)SIGTSTP);
1184# else /* TCSIG */
1185 *pfrontp++ = slctab[SLC_SUSP].sptr ?
1186 (unsigned char)*slctab[SLC_SUSP].sptr : '\032';
1187# endif /* TCSIG */
1188#endif /* SIGTSTP */
1189}
1190
1191/*
1192 * When we get an AYT, if ^T is enabled, use that. Otherwise,
1193 * just send back "[Yes]".
1194 */
1195void
1196recv_ayt(void)
1197{
1198#if defined(SIGINFO) && defined(TCSIG)
1199 if (slctab[SLC_AYT].sptr && *slctab[SLC_AYT].sptr != _POSIX_VDISABLE) {
1200 (void) ioctl(pty, TCSIG, (char *)SIGINFO);
1201 return;
1202 }
1203#endif
1204 output_data("\r\n[Yes]\r\n");
1205}
1206
1207void
1208doeof(void)
1209{
1210 init_termbuf();
1211
1212#if defined(LINEMODE) && defined(USE_TERMIO) && (VEOF == VMIN)
1213 if (!tty_isediting()) {
1214 extern char oldeofc;
1215 *pfrontp++ = oldeofc;
1216 return;
1217 }
1218#endif
1219 *pfrontp++ = slctab[SLC_EOF].sptr ?
1220 (unsigned char)*slctab[SLC_EOF].sptr : '\004';
1221}