xref: /freebsd/crypto/heimdal/appl/telnet/telnetd/telnetd.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
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.
32  */
33 
34 #include "telnetd.h"
35 
36 RCSID("$Id: telnetd.c,v 1.69.6.1 2004/03/22 18:17:25 lha Exp $");
37 
38 #ifdef _SC_CRAY_SECURE_SYS
39 #include <sys/sysv.h>
40 #include <sys/secdev.h>
41 #include <sys/secparm.h>
42 #include <sys/usrv.h>
43 int	secflag;
44 char	tty_dev[16];
45 struct	secdev dv;
46 struct	sysv sysv;
47 struct	socksec ss;
48 #endif	/* _SC_CRAY_SECURE_SYS */
49 
50 #ifdef AUTHENTICATION
51 int	auth_level = 0;
52 #endif
53 
54 extern	int utmp_len;
55 int	registerd_host_only = 0;
56 
57 #undef NOERROR
58 
59 #ifdef	STREAMSPTY
60 # include <stropts.h>
61 # include <termios.h>
62 #ifdef HAVE_SYS_UIO_H
63 #include <sys/uio.h>
64 #endif /* HAVE_SYS_UIO_H */
65 #ifdef HAVE_SYS_STREAM_H
66 #include <sys/stream.h>
67 #endif
68 
69 #ifdef _AIX
70 #include <sys/termio.h>
71 #endif
72 # ifdef HAVE_SYS_STRTTY_H
73 # include <sys/strtty.h>
74 # endif
75 # ifdef HAVE_SYS_STR_TTY_H
76 # include <sys/str_tty.h>
77 # endif
78 /* make sure we don't get the bsd version */
79 /* what is this here for? solaris? /joda */
80 # ifdef HAVE_SYS_TTY_H
81 # include "/usr/include/sys/tty.h"
82 # endif
83 # ifdef HAVE_SYS_PTYVAR_H
84 # include <sys/ptyvar.h>
85 # endif
86 
87 /*
88  * Because of the way ptyibuf is used with streams messages, we need
89  * ptyibuf+1 to be on a full-word boundary.  The following wierdness
90  * is simply to make that happen.
91  */
92 long	ptyibufbuf[BUFSIZ/sizeof(long)+1];
93 char	*ptyibuf = ((char *)&ptyibufbuf[1])-1;
94 char	*ptyip = ((char *)&ptyibufbuf[1])-1;
95 char	ptyibuf2[BUFSIZ];
96 unsigned char ctlbuf[BUFSIZ];
97 struct	strbuf strbufc, strbufd;
98 
99 int readstream(int, char*, int);
100 
101 #else	/* ! STREAMPTY */
102 
103 /*
104  * I/O data buffers,
105  * pointers, and counters.
106  */
107 char	ptyibuf[BUFSIZ], *ptyip = ptyibuf;
108 char	ptyibuf2[BUFSIZ];
109 
110 #endif /* ! STREAMPTY */
111 
112 int	hostinfo = 1;			/* do we print login banner? */
113 
114 #ifdef	_CRAY
115 extern int      newmap; /* nonzero if \n maps to ^M^J */
116 int	lowpty = 0, highpty;	/* low, high pty numbers */
117 #endif /* CRAY */
118 
119 int debug = 0;
120 int keepalive = 1;
121 char *progname;
122 
123 static void usage (void);
124 
125 /*
126  * The string to pass to getopt().  We do it this way so
127  * that only the actual options that we support will be
128  * passed off to getopt().
129  */
130 char valid_opts[] = "Bd:hklnS:u:UL:y"
131 #ifdef AUTHENTICATION
132 		    "a:X:z"
133 #endif
134 #ifdef DIAGNOSTICS
135 		    "D:"
136 #endif
137 #ifdef _CRAY
138 		    "r:"
139 #endif
140 		    ;
141 
142 static void doit(struct sockaddr*, int);
143 
144 #ifdef ENCRYPTION
145 extern int des_check_key;
146 #endif
147 
148 int
149 main(int argc, char **argv)
150 {
151     struct sockaddr_storage __ss;
152     struct sockaddr *sa = (struct sockaddr *)&__ss;
153     int on = 1;
154     socklen_t sa_size;
155     int ch;
156 #if	defined(IPPROTO_IP) && defined(IP_TOS)
157     int tos = -1;
158 #endif
159 #ifdef ENCRYPTION
160     des_check_key = 1;	/* Kludge for Mac NCSA telnet 2.6 /bg */
161 #endif
162     pfrontp = pbackp = ptyobuf;
163     netip = netibuf;
164     nfrontp = nbackp = netobuf;
165 
166     setprogname(argv[0]);
167 
168     progname = *argv;
169 #ifdef ENCRYPTION
170     nclearto = 0;
171 #endif
172 
173 #ifdef _CRAY
174     /*
175      * Get number of pty's before trying to process options,
176      * which may include changing pty range.
177      */
178     highpty = getnpty();
179 #endif /* CRAY */
180 
181     if (argc == 2 && strcmp(argv[1], "--version") == 0) {
182 	print_version(NULL);
183 	exit(0);
184     }
185 
186     while ((ch = getopt(argc, argv, valid_opts)) != -1) {
187 	switch(ch) {
188 
189 #ifdef	AUTHENTICATION
190 	case 'a':
191 	    /*
192 	     * Check for required authentication level
193 	     */
194 	    if (strcmp(optarg, "debug") == 0) {
195 		auth_debug_mode = 1;
196 	    } else if (strcasecmp(optarg, "none") == 0) {
197 		auth_level = 0;
198 	    } else if (strcasecmp(optarg, "otp") == 0) {
199 		auth_level = 0;
200 		require_otp = 1;
201 	    } else if (strcasecmp(optarg, "other") == 0) {
202 		auth_level = AUTH_OTHER;
203 	    } else if (strcasecmp(optarg, "user") == 0) {
204 		auth_level = AUTH_USER;
205 	    } else if (strcasecmp(optarg, "valid") == 0) {
206 		auth_level = AUTH_VALID;
207 	    } else if (strcasecmp(optarg, "off") == 0) {
208 		/*
209 		 * This hack turns off authentication
210 		 */
211 		auth_level = -1;
212 	    } else {
213 		fprintf(stderr,
214 			"telnetd: unknown authorization level for -a\n");
215 	    }
216 	    break;
217 #endif	/* AUTHENTICATION */
218 
219 	case 'B': /* BFTP mode is not supported any more */
220 	    break;
221 	case 'd':
222 	    if (strcmp(optarg, "ebug") == 0) {
223 		debug++;
224 		break;
225 	    }
226 	    usage();
227 	    /* NOTREACHED */
228 	    break;
229 
230 #ifdef DIAGNOSTICS
231 	case 'D':
232 	    /*
233 	     * Check for desired diagnostics capabilities.
234 	     */
235 	    if (!strcmp(optarg, "report")) {
236 		diagnostic |= TD_REPORT|TD_OPTIONS;
237 	    } else if (!strcmp(optarg, "exercise")) {
238 		diagnostic |= TD_EXERCISE;
239 	    } else if (!strcmp(optarg, "netdata")) {
240 		diagnostic |= TD_NETDATA;
241 	    } else if (!strcmp(optarg, "ptydata")) {
242 		diagnostic |= TD_PTYDATA;
243 	    } else if (!strcmp(optarg, "options")) {
244 		diagnostic |= TD_OPTIONS;
245 	    } else {
246 		usage();
247 		/* NOT REACHED */
248 	    }
249 	    break;
250 #endif /* DIAGNOSTICS */
251 
252 
253 	case 'h':
254 	    hostinfo = 0;
255 	    break;
256 
257 	case 'k': /* Linemode is not supported any more */
258 	case 'l':
259 	    break;
260 
261 	case 'n':
262 	    keepalive = 0;
263 	    break;
264 
265 #ifdef _CRAY
266 	case 'r':
267 	    {
268 		char *strchr();
269 		char *c;
270 
271 		/*
272 		 * Allow the specification of alterations
273 		 * to the pty search range.  It is legal to
274 		 * specify only one, and not change the
275 		 * other from its default.
276 		 */
277 		c = strchr(optarg, '-');
278 		if (c) {
279 		    *c++ = '\0';
280 		    highpty = atoi(c);
281 		}
282 		if (*optarg != '\0')
283 		    lowpty = atoi(optarg);
284 		if ((lowpty > highpty) || (lowpty < 0) ||
285 		    (highpty > 32767)) {
286 		    usage();
287 		    /* NOT REACHED */
288 		}
289 		break;
290 	    }
291 #endif	/* CRAY */
292 
293 	case 'S':
294 #ifdef	HAVE_PARSETOS
295 	    if ((tos = parsetos(optarg, "tcp")) < 0)
296 		fprintf(stderr, "%s%s%s\n",
297 			"telnetd: Bad TOS argument '", optarg,
298 			"'; will try to use default TOS");
299 #else
300 	    fprintf(stderr, "%s%s\n", "TOS option unavailable; ",
301 		    "-S flag not supported\n");
302 #endif
303 	    break;
304 
305 	case 'u': {
306 	    char *eptr;
307 
308 	    utmp_len = strtol(optarg, &eptr, 0);
309 	    if (optarg == eptr)
310 		fprintf(stderr, "telnetd: unknown utmp len (%s)\n", optarg);
311 	    break;
312 	}
313 
314 	case 'U':
315 	    registerd_host_only = 1;
316 	    break;
317 
318 #ifdef	AUTHENTICATION
319 	case 'X':
320 	    /*
321 	     * Check for invalid authentication types
322 	     */
323 	    auth_disable_name(optarg);
324 	    break;
325 #endif
326 	case 'y':
327 	    no_warn = 1;
328 	    break;
329 #ifdef AUTHENTICATION
330 	case 'z':
331 	    log_unauth = 1;
332 	    break;
333 
334 #endif	/* AUTHENTICATION */
335 
336 	case 'L':
337 	    new_login = optarg;
338 	    break;
339 
340 	default:
341 	    fprintf(stderr, "telnetd: %c: unknown option\n", ch);
342 	    /* FALLTHROUGH */
343 	case '?':
344 	    usage();
345 	    /* NOTREACHED */
346 	}
347     }
348 
349     argc -= optind;
350     argv += optind;
351 
352     if (debug) {
353 	int port = 0;
354 	struct servent *sp;
355 
356 	if (argc > 1) {
357 	    usage ();
358 	} else if (argc == 1) {
359 	    sp = roken_getservbyname (*argv, "tcp");
360 	    if (sp)
361 		port = sp->s_port;
362 	    else
363 		port = htons(atoi(*argv));
364 	} else {
365 #ifdef KRB5
366 	    port = krb5_getportbyname (NULL, "telnet", "tcp", 23);
367 #else
368 	    port = k_getportbyname("telnet", "tcp", htons(23));
369 #endif
370 	}
371 	mini_inetd (port);
372     } else if (argc > 0) {
373 	usage();
374 	/* NOT REACHED */
375     }
376 
377 #ifdef _SC_CRAY_SECURE_SYS
378     secflag = sysconf(_SC_CRAY_SECURE_SYS);
379 
380     /*
381      *	Get socket's security label
382      */
383     if (secflag)  {
384 	socklen_t szss = sizeof(ss);
385 	int sock_multi;
386 	socklen_t szi = sizeof(int);
387 
388 	memset(&dv, 0, sizeof(dv));
389 
390 	if (getsysv(&sysv, sizeof(struct sysv)) != 0)
391 	    fatalperror(net, "getsysv");
392 
393 	/*
394 	 *	Get socket security label and set device values
395 	 *	   {security label to be set on ttyp device}
396 	 */
397 #ifdef SO_SEC_MULTI			/* 8.0 code */
398 	if ((getsockopt(0, SOL_SOCKET, SO_SECURITY,
399 			(void *)&ss, &szss) < 0) ||
400 	    (getsockopt(0, SOL_SOCKET, SO_SEC_MULTI,
401 			(void *)&sock_multi, &szi) < 0))
402 	    fatalperror(net, "getsockopt");
403 	else {
404 	    dv.dv_actlvl = ss.ss_actlabel.lt_level;
405 	    dv.dv_actcmp = ss.ss_actlabel.lt_compart;
406 	    if (!sock_multi) {
407 		dv.dv_minlvl = dv.dv_maxlvl = dv.dv_actlvl;
408 		dv.dv_valcmp = dv.dv_actcmp;
409 	    } else {
410 		dv.dv_minlvl = ss.ss_minlabel.lt_level;
411 		dv.dv_maxlvl = ss.ss_maxlabel.lt_level;
412 		dv.dv_valcmp = ss.ss_maxlabel.lt_compart;
413 	    }
414 	    dv.dv_devflg = 0;
415 	}
416 #else /* SO_SEC_MULTI */		/* 7.0 code */
417 	if (getsockopt(0, SOL_SOCKET, SO_SECURITY,
418 		       (void *)&ss, &szss) >= 0) {
419 	    dv.dv_actlvl = ss.ss_slevel;
420 	    dv.dv_actcmp = ss.ss_compart;
421 	    dv.dv_minlvl = ss.ss_minlvl;
422 	    dv.dv_maxlvl = ss.ss_maxlvl;
423 	    dv.dv_valcmp = ss.ss_maxcmp;
424 	}
425 #endif /* SO_SEC_MULTI */
426     }
427 #endif	/* _SC_CRAY_SECURE_SYS */
428 
429     roken_openlog("telnetd", LOG_PID | LOG_ODELAY, LOG_DAEMON);
430     sa_size = sizeof (__ss);
431     if (getpeername(STDIN_FILENO, sa, &sa_size) < 0) {
432 	fprintf(stderr, "%s: ", progname);
433 	perror("getpeername");
434 	_exit(1);
435     }
436     if (keepalive &&
437 	setsockopt(STDIN_FILENO, SOL_SOCKET, SO_KEEPALIVE,
438 		   (void *)&on, sizeof (on)) < 0) {
439 	syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
440     }
441 
442 #if	defined(IPPROTO_IP) && defined(IP_TOS) && defined(HAVE_SETSOCKOPT)
443     {
444 # ifdef HAVE_GETTOSBYNAME
445 	struct tosent *tp;
446 	if (tos < 0 && (tp = gettosbyname("telnet", "tcp")))
447 	    tos = tp->t_tos;
448 # endif
449 	if (tos < 0)
450 	    tos = 020;	/* Low Delay bit */
451 	if (tos
452 	    && sa->sa_family == AF_INET
453 	    && (setsockopt(STDIN_FILENO, IPPROTO_IP, IP_TOS,
454 			   (void *)&tos, sizeof(tos)) < 0)
455 	    && (errno != ENOPROTOOPT) )
456 	    syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
457     }
458 #endif	/* defined(IPPROTO_IP) && defined(IP_TOS) */
459     net = STDIN_FILENO;
460     doit(sa, sa_size);
461     /* NOTREACHED */
462     return 0;
463 }  /* end of main */
464 
465 static void
466 usage(void)
467 {
468     fprintf(stderr, "Usage: telnetd");
469 #ifdef	AUTHENTICATION
470     fprintf(stderr, " [-a (debug|other|otp|user|valid|off|none)]\n\t");
471 #endif
472     fprintf(stderr, " [-debug]");
473 #ifdef DIAGNOSTICS
474     fprintf(stderr, " [-D (options|report|exercise|netdata|ptydata)]\n\t");
475 #endif
476 #ifdef	AUTHENTICATION
477     fprintf(stderr, " [-edebug]");
478 #endif
479     fprintf(stderr, " [-h]");
480     fprintf(stderr, " [-L login]");
481     fprintf(stderr, " [-n]");
482 #ifdef	_CRAY
483     fprintf(stderr, " [-r[lowpty]-[highpty]]");
484 #endif
485     fprintf(stderr, "\n\t");
486 #ifdef	HAVE_GETTOSBYNAME
487     fprintf(stderr, " [-S tos]");
488 #endif
489 #ifdef	AUTHENTICATION
490     fprintf(stderr, " [-X auth-type] [-y] [-z]");
491 #endif
492     fprintf(stderr, " [-u utmp_hostname_length] [-U]");
493     fprintf(stderr, " [port]\n");
494     exit(1);
495 }
496 
497 /*
498  * getterminaltype
499  *
500  *	Ask the other end to send along its terminal type and speed.
501  * Output is the variable terminaltype filled in.
502  */
503 static unsigned char ttytype_sbbuf[] = {
504     IAC, SB, TELOPT_TTYPE, TELQUAL_SEND, IAC, SE
505 };
506 
507 int
508 getterminaltype(char *name, size_t name_sz)
509 {
510     int retval = -1;
511 
512     settimer(baseline);
513 #ifdef AUTHENTICATION
514     /*
515      * Handle the Authentication option before we do anything else.
516      */
517     send_do(TELOPT_AUTHENTICATION, 1);
518     while (his_will_wont_is_changing(TELOPT_AUTHENTICATION))
519 	ttloop();
520     if (his_state_is_will(TELOPT_AUTHENTICATION)) {
521 	retval = auth_wait(name, name_sz);
522     }
523 #endif
524 
525 #ifdef ENCRYPTION
526     send_will(TELOPT_ENCRYPT, 1);
527     send_do(TELOPT_ENCRYPT, 1);	/* esc@magic.fi */
528 #endif
529     send_do(TELOPT_TTYPE, 1);
530     send_do(TELOPT_TSPEED, 1);
531     send_do(TELOPT_XDISPLOC, 1);
532     send_do(TELOPT_NEW_ENVIRON, 1);
533     send_do(TELOPT_OLD_ENVIRON, 1);
534     while (
535 #ifdef ENCRYPTION
536 	   his_do_dont_is_changing(TELOPT_ENCRYPT) ||
537 #endif
538 	   his_will_wont_is_changing(TELOPT_TTYPE) ||
539 	   his_will_wont_is_changing(TELOPT_TSPEED) ||
540 	   his_will_wont_is_changing(TELOPT_XDISPLOC) ||
541 	   his_will_wont_is_changing(TELOPT_NEW_ENVIRON) ||
542 	   his_will_wont_is_changing(TELOPT_OLD_ENVIRON)) {
543 	ttloop();
544     }
545 #ifdef ENCRYPTION
546     /*
547      * Wait for the negotiation of what type of encryption we can
548      * send with.  If autoencrypt is not set, this will just return.
549      */
550     if (his_state_is_will(TELOPT_ENCRYPT)) {
551 	encrypt_wait();
552     }
553 #endif
554     if (his_state_is_will(TELOPT_TSPEED)) {
555 	static unsigned char sb[] =
556 	{ IAC, SB, TELOPT_TSPEED, TELQUAL_SEND, IAC, SE };
557 
558 	telnet_net_write (sb, sizeof sb);
559 	DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
560     }
561     if (his_state_is_will(TELOPT_XDISPLOC)) {
562 	static unsigned char sb[] =
563 	{ IAC, SB, TELOPT_XDISPLOC, TELQUAL_SEND, IAC, SE };
564 
565 	telnet_net_write (sb, sizeof sb);
566 	DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
567     }
568     if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
569 	static unsigned char sb[] =
570 	{ IAC, SB, TELOPT_NEW_ENVIRON, TELQUAL_SEND, IAC, SE };
571 
572 	telnet_net_write (sb, sizeof sb);
573 	DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
574     }
575     else if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
576 	static unsigned char sb[] =
577 	{ IAC, SB, TELOPT_OLD_ENVIRON, TELQUAL_SEND, IAC, SE };
578 
579 	telnet_net_write (sb, sizeof sb);
580 	DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
581     }
582     if (his_state_is_will(TELOPT_TTYPE)) {
583 
584 	telnet_net_write (ttytype_sbbuf, sizeof ttytype_sbbuf);
585 	DIAG(TD_OPTIONS, printsub('>', ttytype_sbbuf + 2,
586 				  sizeof ttytype_sbbuf - 2););
587     }
588     if (his_state_is_will(TELOPT_TSPEED)) {
589 	while (sequenceIs(tspeedsubopt, baseline))
590 	    ttloop();
591     }
592     if (his_state_is_will(TELOPT_XDISPLOC)) {
593 	while (sequenceIs(xdisplocsubopt, baseline))
594 	    ttloop();
595     }
596     if (his_state_is_will(TELOPT_NEW_ENVIRON)) {
597 	while (sequenceIs(environsubopt, baseline))
598 	    ttloop();
599     }
600     if (his_state_is_will(TELOPT_OLD_ENVIRON)) {
601 	while (sequenceIs(oenvironsubopt, baseline))
602 	    ttloop();
603     }
604     if (his_state_is_will(TELOPT_TTYPE)) {
605 	char first[256], last[256];
606 
607 	while (sequenceIs(ttypesubopt, baseline))
608 	    ttloop();
609 
610 	/*
611 	 * If the other side has already disabled the option, then
612 	 * we have to just go with what we (might) have already gotten.
613 	 */
614 	if (his_state_is_will(TELOPT_TTYPE) && !terminaltypeok(terminaltype)) {
615 	    strlcpy(first, terminaltype, sizeof(first));
616 	    for(;;) {
617 		/*
618 		 * Save the unknown name, and request the next name.
619 		 */
620 		strlcpy(last, terminaltype, sizeof(last));
621 		_gettermname();
622 		if (terminaltypeok(terminaltype))
623 		    break;
624 		if ((strncmp(last, terminaltype, sizeof(last)) == 0) ||
625 		    his_state_is_wont(TELOPT_TTYPE)) {
626 		    /*
627 		     * We've hit the end.  If this is the same as
628 		     * the first name, just go with it.
629 		     */
630 		    if (strncmp(first, terminaltype, sizeof(first)) == 0)
631 			break;
632 		    /*
633 		     * Get the terminal name one more time, so that
634 		     * RFC1091 compliant telnets will cycle back to
635 		     * the start of the list.
636 		     */
637 		    _gettermname();
638 		    if (strncmp(first, terminaltype, sizeof(first)) != 0)
639 			strcpy(terminaltype, first);
640 		    break;
641 		}
642 	    }
643 	}
644     }
645     return(retval);
646 }  /* end of getterminaltype */
647 
648 void
649 _gettermname(void)
650 {
651     /*
652      * If the client turned off the option,
653      * we can't send another request, so we
654      * just return.
655      */
656     if (his_state_is_wont(TELOPT_TTYPE))
657 	return;
658     settimer(baseline);
659     telnet_net_write (ttytype_sbbuf, sizeof ttytype_sbbuf);
660     DIAG(TD_OPTIONS, printsub('>', ttytype_sbbuf + 2,
661 			      sizeof ttytype_sbbuf - 2););
662     while (sequenceIs(ttypesubopt, baseline))
663 	ttloop();
664 }
665 
666 int
667 terminaltypeok(char *s)
668 {
669     return 1;
670 }
671 
672 
673 char host_name[MaxHostNameLen];
674 char remote_host_name[MaxHostNameLen];
675 char remote_utmp_name[MaxHostNameLen];
676 
677 /*
678  * Get a pty, scan input lines.
679  */
680 static void
681 doit(struct sockaddr *who, int who_len)
682 {
683     int level;
684     int ptynum;
685     char user_name[256];
686     int error;
687 
688     /*
689      * Find an available pty to use.
690      */
691     ourpty = getpty(&ptynum);
692     if (ourpty < 0)
693 	fatal(net, "All network ports in use");
694 
695 #ifdef _SC_CRAY_SECURE_SYS
696     /*
697      *	set ttyp line security label
698      */
699     if (secflag) {
700 	char slave_dev[16];
701 
702 	snprintf(tty_dev, sizeof(tty_dev), "/dev/pty/%03d", ptynum);
703 	if (setdevs(tty_dev, &dv) < 0)
704 	    fatal(net, "cannot set pty security");
705 	snprintf(slave_dev, sizeof(slave_dev), "/dev/ttyp%03d", ptynum);
706 	if (setdevs(slave_dev, &dv) < 0)
707 	    fatal(net, "cannot set tty security");
708     }
709 #endif	/* _SC_CRAY_SECURE_SYS */
710 
711     error = getnameinfo_verified (who, who_len,
712 				  remote_host_name,
713 				  sizeof(remote_host_name),
714 				  NULL, 0,
715 				  registerd_host_only ? NI_NAMEREQD : 0);
716     if (error)
717 	fatal(net, "Couldn't resolve your address into a host name.\r\n\
718 Please contact your net administrator");
719 
720     gethostname(host_name, sizeof (host_name));
721 
722     strlcpy (remote_utmp_name, remote_host_name, sizeof(remote_utmp_name));
723 
724     /* Only trim if too long (and possible) */
725     if (strlen(remote_utmp_name) > utmp_len) {
726 	char *domain = strchr(host_name, '.');
727 	char *p = strchr(remote_utmp_name, '.');
728 	if (domain != NULL && p != NULL && (strcmp(p, domain) == 0))
729 	    *p = '\0'; /* remove domain part */
730     }
731 
732     /*
733      * If hostname still doesn't fit utmp, use ipaddr.
734      */
735     if (strlen(remote_utmp_name) > utmp_len) {
736 	error = getnameinfo (who, who_len,
737 			     remote_utmp_name,
738 			     sizeof(remote_utmp_name),
739 			     NULL, 0,
740 			     NI_NUMERICHOST);
741 	if (error)
742 	    fatal(net, "Couldn't get numeric address\r\n");
743     }
744 
745 #ifdef AUTHENTICATION
746     auth_encrypt_init(host_name, remote_host_name, "TELNETD", 1);
747 #endif
748 
749     init_env();
750     /*
751      * get terminal type.
752      */
753     *user_name = 0;
754     level = getterminaltype(user_name, sizeof(user_name));
755     esetenv("TERM", terminaltype ? terminaltype : "network", 1);
756 
757 #ifdef _SC_CRAY_SECURE_SYS
758     if (secflag) {
759 	if (setulvl(dv.dv_actlvl) < 0)
760 	    fatal(net,"cannot setulvl()");
761 	if (setucmp(dv.dv_actcmp) < 0)
762 	    fatal(net, "cannot setucmp()");
763     }
764 #endif	/* _SC_CRAY_SECURE_SYS */
765 
766     /* begin server processing */
767     my_telnet(net, ourpty, remote_host_name, remote_utmp_name,
768 	      level, user_name);
769     /*NOTREACHED*/
770 }  /* end of doit */
771 
772 /* output contents of /etc/issue.net, or /etc/issue */
773 static void
774 show_issue(void)
775 {
776     FILE *f;
777     char buf[128];
778     f = fopen(SYSCONFDIR "/issue.net", "r");
779     if(f == NULL)
780 	f = fopen(SYSCONFDIR "/issue", "r");
781     if(f){
782 	while(fgets(buf, sizeof(buf)-2, f)){
783 	    strcpy(buf + strcspn(buf, "\r\n"), "\r\n");
784 	    writenet((unsigned char*)buf, strlen(buf));
785 	}
786 	fclose(f);
787     }
788 }
789 
790 /*
791  * Main loop.  Select from pty and network, and
792  * hand data to telnet receiver finite state machine.
793  */
794 void
795 my_telnet(int f, int p, const char *host, const char *utmp_host,
796 	  int level, char *autoname)
797 {
798     int on = 1;
799     char *he;
800     char *IM;
801     int nfd;
802     int startslave_called = 0;
803     time_t timeout;
804 
805     /*
806      * Initialize the slc mapping table.
807      */
808     get_slc_defaults();
809 
810     /*
811      * Do some tests where it is desireable to wait for a response.
812      * Rather than doing them slowly, one at a time, do them all
813      * at once.
814      */
815     if (my_state_is_wont(TELOPT_SGA))
816 	send_will(TELOPT_SGA, 1);
817     /*
818      * Is the client side a 4.2 (NOT 4.3) system?  We need to know this
819      * because 4.2 clients are unable to deal with TCP urgent data.
820      *
821      * To find out, we send out a "DO ECHO".  If the remote system
822      * answers "WILL ECHO" it is probably a 4.2 client, and we note
823      * that fact ("WILL ECHO" ==> that the client will echo what
824      * WE, the server, sends it; it does NOT mean that the client will
825      * echo the terminal input).
826      */
827     send_do(TELOPT_ECHO, 1);
828 
829     /*
830      * Send along a couple of other options that we wish to negotiate.
831      */
832     send_do(TELOPT_NAWS, 1);
833     send_will(TELOPT_STATUS, 1);
834     flowmode = 1;		/* default flow control state */
835     restartany = -1;	/* uninitialized... */
836     send_do(TELOPT_LFLOW, 1);
837 
838     /*
839      * Spin, waiting for a response from the DO ECHO.  However,
840      * some REALLY DUMB telnets out there might not respond
841      * to the DO ECHO.  So, we spin looking for NAWS, (most dumb
842      * telnets so far seem to respond with WONT for a DO that
843      * they don't understand...) because by the time we get the
844      * response, it will already have processed the DO ECHO.
845      * Kludge upon kludge.
846      */
847     while (his_will_wont_is_changing(TELOPT_NAWS))
848 	ttloop();
849 
850     /*
851      * But...
852      * The client might have sent a WILL NAWS as part of its
853      * startup code; if so, we'll be here before we get the
854      * response to the DO ECHO.  We'll make the assumption
855      * that any implementation that understands about NAWS
856      * is a modern enough implementation that it will respond
857      * to our DO ECHO request; hence we'll do another spin
858      * waiting for the ECHO option to settle down, which is
859      * what we wanted to do in the first place...
860      */
861     if (his_want_state_is_will(TELOPT_ECHO) &&
862 	his_state_is_will(TELOPT_NAWS)) {
863 	while (his_will_wont_is_changing(TELOPT_ECHO))
864 	    ttloop();
865     }
866     /*
867      * On the off chance that the telnet client is broken and does not
868      * respond to the DO ECHO we sent, (after all, we did send the
869      * DO NAWS negotiation after the DO ECHO, and we won't get here
870      * until a response to the DO NAWS comes back) simulate the
871      * receipt of a will echo.  This will also send a WONT ECHO
872      * to the client, since we assume that the client failed to
873      * respond because it believes that it is already in DO ECHO
874      * mode, which we do not want.
875      */
876     if (his_want_state_is_will(TELOPT_ECHO)) {
877 	DIAG(TD_OPTIONS,
878 	     {output_data("td: simulating recv\r\n");
879 	     });
880 	willoption(TELOPT_ECHO);
881     }
882 
883     /*
884      * Finally, to clean things up, we turn on our echo.  This
885      * will break stupid 4.2 telnets out of local terminal echo.
886      */
887 
888     if (my_state_is_wont(TELOPT_ECHO))
889 	send_will(TELOPT_ECHO, 1);
890 
891 #ifdef TIOCPKT
892 #ifdef	STREAMSPTY
893     if (!really_stream)
894 #endif
895 	/*
896 	 * Turn on packet mode
897 	 */
898 	ioctl(p, TIOCPKT, (char *)&on);
899 #endif
900 
901 
902     /*
903      * Call telrcv() once to pick up anything received during
904      * terminal type negotiation, 4.2/4.3 determination, and
905      * linemode negotiation.
906      */
907     telrcv();
908 
909     ioctl(f, FIONBIO, (char *)&on);
910     ioctl(p, FIONBIO, (char *)&on);
911 
912 #if	defined(SO_OOBINLINE) && defined(HAVE_SETSOCKOPT)
913     setsockopt(net, SOL_SOCKET, SO_OOBINLINE,
914 	       (void *)&on, sizeof on);
915 #endif	/* defined(SO_OOBINLINE) */
916 
917 #ifdef	SIGTSTP
918     signal(SIGTSTP, SIG_IGN);
919 #endif
920 #ifdef	SIGTTOU
921     /*
922      * Ignoring SIGTTOU keeps the kernel from blocking us
923      * in ttioct() in /sys/tty.c.
924      */
925     signal(SIGTTOU, SIG_IGN);
926 #endif
927 
928     signal(SIGCHLD, cleanup);
929 
930 #ifdef  TIOCNOTTY
931     {
932 	int t;
933 	t = open(_PATH_TTY, O_RDWR);
934 	if (t >= 0) {
935 	    ioctl(t, TIOCNOTTY, (char *)0);
936 	    close(t);
937 	}
938     }
939 #endif
940 
941     show_issue();
942     /*
943      * Show banner that getty never gave.
944      *
945      * We put the banner in the pty input buffer.  This way, it
946      * gets carriage return null processing, etc., just like all
947      * other pty --> client data.
948      */
949 
950     if (getenv("USER"))
951 	hostinfo = 0;
952 
953     IM = DEFAULT_IM;
954     he = 0;
955     edithost(he, host_name);
956     if (hostinfo && *IM)
957 	putf(IM, ptyibuf2);
958 
959     if (pcc)
960 	strncat(ptyibuf2, ptyip, pcc+1);
961     ptyip = ptyibuf2;
962     pcc = strlen(ptyip);
963 
964     DIAG(TD_REPORT, {
965 	output_data("td: Entering processing loop\r\n");
966     });
967 
968 
969     nfd = ((f > p) ? f : p) + 1;
970     timeout = time(NULL) + 5;
971     for (;;) {
972 	fd_set ibits, obits, xbits;
973 	int c;
974 
975 	/* wait for encryption to be turned on, but don't wait
976            indefinitely */
977 	if(!startslave_called && (!encrypt_delay() || timeout > time(NULL))){
978 	    startslave_called = 1;
979 	    startslave(host, utmp_host, level, autoname);
980 	}
981 
982 	if (ncc < 0 && pcc < 0)
983 	    break;
984 
985 	FD_ZERO(&ibits);
986 	FD_ZERO(&obits);
987 	FD_ZERO(&xbits);
988 
989 	if (f >= FD_SETSIZE
990 	    || p >= FD_SETSIZE)
991 	    fatal(net, "fd too large");
992 
993 	/*
994 	 * Never look for input if there's still
995 	 * stuff in the corresponding output buffer
996 	 */
997 	if (nfrontp - nbackp || pcc > 0) {
998 	    FD_SET(f, &obits);
999 	} else {
1000 	    FD_SET(p, &ibits);
1001 	}
1002 	if (pfrontp - pbackp || ncc > 0) {
1003 	    FD_SET(p, &obits);
1004 	} else {
1005 	    FD_SET(f, &ibits);
1006 	}
1007 	if (!SYNCHing) {
1008 	    FD_SET(f, &xbits);
1009 	}
1010 	if ((c = select(nfd, &ibits, &obits, &xbits,
1011 			(struct timeval *)0)) < 1) {
1012 	    if (c == -1) {
1013 		if (errno == EINTR) {
1014 		    continue;
1015 		}
1016 	    }
1017 	    sleep(5);
1018 	    continue;
1019 	}
1020 
1021 	/*
1022 	 * Any urgent data?
1023 	 */
1024 	if (FD_ISSET(net, &xbits)) {
1025 	    SYNCHing = 1;
1026 	}
1027 
1028 	/*
1029 	 * Something to read from the network...
1030 	 */
1031 	if (FD_ISSET(net, &ibits)) {
1032 #ifndef SO_OOBINLINE
1033 	    /*
1034 	     * In 4.2 (and 4.3 beta) systems, the
1035 	     * OOB indication and data handling in the kernel
1036 	     * is such that if two separate TCP Urgent requests
1037 	     * come in, one byte of TCP data will be overlaid.
1038 	     * This is fatal for Telnet, but we try to live
1039 	     * with it.
1040 	     *
1041 	     * In addition, in 4.2 (and...), a special protocol
1042 	     * is needed to pick up the TCP Urgent data in
1043 	     * the correct sequence.
1044 	     *
1045 	     * What we do is:  if we think we are in urgent
1046 	     * mode, we look to see if we are "at the mark".
1047 	     * If we are, we do an OOB receive.  If we run
1048 	     * this twice, we will do the OOB receive twice,
1049 	     * but the second will fail, since the second
1050 	     * time we were "at the mark", but there wasn't
1051 	     * any data there (the kernel doesn't reset
1052 	     * "at the mark" until we do a normal read).
1053 	     * Once we've read the OOB data, we go ahead
1054 	     * and do normal reads.
1055 	     *
1056 	     * There is also another problem, which is that
1057 	     * since the OOB byte we read doesn't put us
1058 	     * out of OOB state, and since that byte is most
1059 	     * likely the TELNET DM (data mark), we would
1060 	     * stay in the TELNET SYNCH (SYNCHing) state.
1061 	     * So, clocks to the rescue.  If we've "just"
1062 	     * received a DM, then we test for the
1063 	     * presence of OOB data when the receive OOB
1064 	     * fails (and AFTER we did the normal mode read
1065 	     * to clear "at the mark").
1066 	     */
1067 	    if (SYNCHing) {
1068 		int atmark;
1069 
1070 		ioctl(net, SIOCATMARK, (char *)&atmark);
1071 		if (atmark) {
1072 		    ncc = recv(net, netibuf, sizeof (netibuf), MSG_OOB);
1073 		    if ((ncc == -1) && (errno == EINVAL)) {
1074 			ncc = read(net, netibuf, sizeof (netibuf));
1075 			if (sequenceIs(didnetreceive, gotDM)) {
1076 			    SYNCHing = stilloob(net);
1077 			}
1078 		    }
1079 		} else {
1080 		    ncc = read(net, netibuf, sizeof (netibuf));
1081 		}
1082 	    } else {
1083 		ncc = read(net, netibuf, sizeof (netibuf));
1084 	    }
1085 	    settimer(didnetreceive);
1086 #else	/* !defined(SO_OOBINLINE)) */
1087 	    ncc = read(net, netibuf, sizeof (netibuf));
1088 #endif	/* !defined(SO_OOBINLINE)) */
1089 	    if (ncc < 0 && errno == EWOULDBLOCK)
1090 		ncc = 0;
1091 	    else {
1092 		if (ncc <= 0) {
1093 		    break;
1094 		}
1095 		netip = netibuf;
1096 	    }
1097 	    DIAG((TD_REPORT | TD_NETDATA), {
1098 		output_data("td: netread %d chars\r\n", ncc);
1099 		});
1100 	    DIAG(TD_NETDATA, printdata("nd", netip, ncc));
1101 	}
1102 
1103 	/*
1104 	 * Something to read from the pty...
1105 	 */
1106 	if (FD_ISSET(p, &ibits)) {
1107 #ifdef STREAMSPTY
1108 	    if (really_stream)
1109 		pcc = readstream(p, ptyibuf, BUFSIZ);
1110 	    else
1111 #endif
1112 		pcc = read(p, ptyibuf, BUFSIZ);
1113 
1114 	    /*
1115 	     * On some systems, if we try to read something
1116 	     * off the master side before the slave side is
1117 	     * opened, we get EIO.
1118 	     */
1119 	    if (pcc < 0 && (errno == EWOULDBLOCK ||
1120 #ifdef	EAGAIN
1121 			    errno == EAGAIN ||
1122 #endif
1123 			    errno == EIO)) {
1124 		pcc = 0;
1125 	    } else {
1126 		if (pcc <= 0)
1127 		    break;
1128 		if (ptyibuf[0] & TIOCPKT_FLUSHWRITE) {
1129 		    netclear();	/* clear buffer back */
1130 #ifndef	NO_URGENT
1131 		    /*
1132 		     * There are client telnets on some
1133 		     * operating systems get screwed up
1134 		     * royally if we send them urgent
1135 		     * mode data.
1136 		     */
1137 		    output_data ("%c%c", IAC, DM);
1138 
1139 		    neturg = nfrontp-1; /* off by one XXX */
1140 		    DIAG(TD_OPTIONS,
1141 			 printoption("td: send IAC", DM));
1142 
1143 #endif
1144 		}
1145 		if (his_state_is_will(TELOPT_LFLOW) &&
1146 		    (ptyibuf[0] &
1147 		     (TIOCPKT_NOSTOP|TIOCPKT_DOSTOP))) {
1148 		    int newflow =
1149 			ptyibuf[0] & TIOCPKT_DOSTOP ? 1 : 0;
1150 		    if (newflow != flowmode) {
1151 			flowmode = newflow;
1152 			output_data("%c%c%c%c%c%c",
1153 				    IAC, SB, TELOPT_LFLOW,
1154 				    flowmode ? LFLOW_ON
1155 				    : LFLOW_OFF,
1156 				    IAC, SE);
1157 			DIAG(TD_OPTIONS, printsub('>',
1158 						  (unsigned char *)nfrontp-4,
1159 						  4););
1160 		    }
1161 		}
1162 		pcc--;
1163 		ptyip = ptyibuf+1;
1164 	    }
1165 	}
1166 
1167 	while (pcc > 0) {
1168 	    if ((&netobuf[BUFSIZ] - nfrontp) < 3)
1169 		break;
1170 	    c = *ptyip++ & 0377, pcc--;
1171 	    if (c == IAC)
1172 		*nfrontp++ = c;
1173 	    *nfrontp++ = c;
1174 	    if ((c == '\r') && (my_state_is_wont(TELOPT_BINARY))) {
1175 		if (pcc > 0 && ((*ptyip & 0377) == '\n')) {
1176 		    *nfrontp++ = *ptyip++ & 0377;
1177 		    pcc--;
1178 		} else
1179 		    *nfrontp++ = '\0';
1180 	    }
1181 	}
1182 
1183 	if (FD_ISSET(f, &obits) && (nfrontp - nbackp) > 0)
1184 	    netflush();
1185 	if (ncc > 0)
1186 	    telrcv();
1187 	if (FD_ISSET(p, &obits) && (pfrontp - pbackp) > 0)
1188 	    ptyflush();
1189     }
1190     cleanup(0);
1191 }
1192 
1193 #ifndef	TCSIG
1194 # ifdef	TIOCSIG
1195 #  define TCSIG TIOCSIG
1196 # endif
1197 #endif
1198 
1199 #ifdef	STREAMSPTY
1200 
1201     int flowison = -1;  /* current state of flow: -1 is unknown */
1202 
1203 int
1204 readstream(int p, char *ibuf, int bufsize)
1205 {
1206     int flags = 0;
1207     int ret = 0;
1208     struct termios *tsp;
1209 #if 0
1210     struct termio *tp;
1211 #endif
1212     struct iocblk *ip;
1213     char vstop, vstart;
1214     int ixon;
1215     int newflow;
1216 
1217     strbufc.maxlen = BUFSIZ;
1218     strbufc.buf = (char *)ctlbuf;
1219     strbufd.maxlen = bufsize-1;
1220     strbufd.len = 0;
1221     strbufd.buf = ibuf+1;
1222     ibuf[0] = 0;
1223 
1224     ret = getmsg(p, &strbufc, &strbufd, &flags);
1225     if (ret < 0)  /* error of some sort -- probably EAGAIN */
1226 	return(-1);
1227 
1228     if (strbufc.len <= 0 || ctlbuf[0] == M_DATA) {
1229 	/* data message */
1230 	if (strbufd.len > 0) {			/* real data */
1231 	    return(strbufd.len + 1);	/* count header char */
1232 	} else {
1233 	    /* nothing there */
1234 	    errno = EAGAIN;
1235 	    return(-1);
1236 	}
1237     }
1238 
1239     /*
1240      * It's a control message.  Return 1, to look at the flag we set
1241      */
1242 
1243     switch (ctlbuf[0]) {
1244     case M_FLUSH:
1245 	if (ibuf[1] & FLUSHW)
1246 	    ibuf[0] = TIOCPKT_FLUSHWRITE;
1247 	return(1);
1248 
1249     case M_IOCTL:
1250 	ip = (struct iocblk *) (ibuf+1);
1251 
1252 	switch (ip->ioc_cmd) {
1253 #ifdef TCSETS
1254 	case TCSETS:
1255 	case TCSETSW:
1256 	case TCSETSF:
1257 	    tsp = (struct termios *)
1258 		(ibuf+1 + sizeof(struct iocblk));
1259 	    vstop = tsp->c_cc[VSTOP];
1260 	    vstart = tsp->c_cc[VSTART];
1261 	    ixon = tsp->c_iflag & IXON;
1262 	    break;
1263 #endif
1264 #if 0
1265 	case TCSETA:
1266 	case TCSETAW:
1267 	case TCSETAF:
1268 	    tp = (struct termio *) (ibuf+1 + sizeof(struct iocblk));
1269 	    vstop = tp->c_cc[VSTOP];
1270 	    vstart = tp->c_cc[VSTART];
1271 	    ixon = tp->c_iflag & IXON;
1272 	    break;
1273 #endif
1274 	default:
1275 	    errno = EAGAIN;
1276 	    return(-1);
1277 	}
1278 
1279 	newflow =  (ixon && (vstart == 021) && (vstop == 023)) ? 1 : 0;
1280 	if (newflow != flowison) {  /* it's a change */
1281 	    flowison = newflow;
1282 	    ibuf[0] = newflow ? TIOCPKT_DOSTOP : TIOCPKT_NOSTOP;
1283 	    return(1);
1284 	}
1285     }
1286 
1287     /* nothing worth doing anything about */
1288     errno = EAGAIN;
1289     return(-1);
1290 }
1291 #endif /* STREAMSPTY */
1292 
1293 /*
1294  * Send interrupt to process on other side of pty.
1295  * If it is in raw mode, just write NULL;
1296  * otherwise, write intr char.
1297  */
1298 void
1299 interrupt()
1300 {
1301     ptyflush();	/* half-hearted */
1302 
1303 #if defined(STREAMSPTY) && defined(TIOCSIGNAL)
1304     /* Streams PTY style ioctl to post a signal */
1305     if (really_stream)
1306 	{
1307 	    int sig = SIGINT;
1308 	    ioctl(ourpty, TIOCSIGNAL, &sig);
1309 	    ioctl(ourpty, I_FLUSH, FLUSHR);
1310 	}
1311 #else
1312 #ifdef	TCSIG
1313     ioctl(ourpty, TCSIG, (char *)SIGINT);
1314 #else	/* TCSIG */
1315     init_termbuf();
1316     *pfrontp++ = slctab[SLC_IP].sptr ?
1317 	(unsigned char)*slctab[SLC_IP].sptr : '\177';
1318 #endif	/* TCSIG */
1319 #endif
1320 }
1321 
1322 /*
1323  * Send quit to process on other side of pty.
1324  * If it is in raw mode, just write NULL;
1325  * otherwise, write quit char.
1326  */
1327 void
1328 sendbrk()
1329 {
1330     ptyflush();	/* half-hearted */
1331 #ifdef	TCSIG
1332     ioctl(ourpty, TCSIG, (char *)SIGQUIT);
1333 #else	/* TCSIG */
1334     init_termbuf();
1335     *pfrontp++ = slctab[SLC_ABORT].sptr ?
1336 	(unsigned char)*slctab[SLC_ABORT].sptr : '\034';
1337 #endif	/* TCSIG */
1338 }
1339 
1340 void
1341 sendsusp()
1342 {
1343 #ifdef	SIGTSTP
1344     ptyflush();	/* half-hearted */
1345 # ifdef	TCSIG
1346     ioctl(ourpty, TCSIG, (char *)SIGTSTP);
1347 # else	/* TCSIG */
1348     *pfrontp++ = slctab[SLC_SUSP].sptr ?
1349 	(unsigned char)*slctab[SLC_SUSP].sptr : '\032';
1350 # endif	/* TCSIG */
1351 #endif	/* SIGTSTP */
1352 }
1353 
1354 /*
1355  * When we get an AYT, if ^T is enabled, use that.  Otherwise,
1356  * just send back "[Yes]".
1357  */
1358 void
1359 recv_ayt()
1360 {
1361 #if	defined(SIGINFO) && defined(TCSIG)
1362     if (slctab[SLC_AYT].sptr && *slctab[SLC_AYT].sptr != _POSIX_VDISABLE) {
1363 	ioctl(ourpty, TCSIG, (char *)SIGINFO);
1364 	return;
1365     }
1366 #endif
1367     output_data("\r\n[Yes]\r\n");
1368 }
1369 
1370 void
1371 doeof()
1372 {
1373     init_termbuf();
1374 
1375     *pfrontp++ = slctab[SLC_EOF].sptr ?
1376 	(unsigned char)*slctab[SLC_EOF].sptr : '\004';
1377 }
1378