1 /*
2 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
3 * Use is subject to license terms.
4 */
5
6 #pragma ident "%Z%%M% %I% %E% SMI"
7
8 /*
9 * Copyright (c) 1988, 1990, 1993
10 * The Regents of the University of California. All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 */
40
41 #ifndef lint
42 static char sccsid[] = "@(#)telnet.c 8.1 (Berkeley) 6/6/93";
43 #endif /* not lint */
44
45 #include <netdb.h>
46 #include <sys/types.h>
47
48 #include <curses.h>
49 #include <signal.h>
50 /*
51 * By the way, we need to include curses.h before telnet.h since,
52 * among other things, telnet.h #defines 'DO', which is a variable
53 * declared in curses.h.
54 */
55
56 #include <arpa/telnet.h>
57
58 #include <ctype.h>
59
60 #include "ring.h"
61
62 #include "defines.h"
63 #include "externs.h"
64 #include "types.h"
65 #include "general.h"
66
67 #include "auth.h"
68 #include "encrypt.h"
69
70 #define strip(x) ((x)&0x7f)
71
72 /* Buffer for sub-options */
73 static unsigned char subbuffer[SUBBUFSIZE];
74 static unsigned char *subpointer;
75 static unsigned char *subend;
76
77 #define SB_CLEAR() subpointer = subbuffer;
78 #define SB_TERM() { subend = subpointer; SB_CLEAR(); }
79 #define SB_ACCUM(c) if (subpointer < (subbuffer+sizeof (subbuffer))) { \
80 *subpointer++ = (c); \
81 }
82
83 #define SB_GET() ((*subpointer++)&0xff)
84 #define SB_PEEK() ((*subpointer)&0xff)
85 #define SB_EOF() (subpointer >= subend)
86 #define SB_LEN() (subend - subpointer)
87
88 char options[SUBBUFSIZE]; /* The combined options */
89 char do_dont_resp[SUBBUFSIZE];
90 char will_wont_resp[SUBBUFSIZE];
91
92 int eight = 0;
93 int autologin = 0; /* Autologin anyone? */
94 int skiprc = 0;
95 int connected;
96 int showoptions;
97 static int ISend; /* trying to send network data in */
98 int debug = 0;
99 int crmod;
100 int netdata; /* Print out network data flow */
101 int crlf; /* Should '\r' be mapped to <CR><LF> (or <CR><NUL>)? */
102 int telnetport;
103 int SYNCHing; /* we are in TELNET SYNCH mode */
104 int flushout; /* flush output */
105 int autoflush = 0; /* flush output when interrupting? */
106 int autosynch; /* send interrupt characters with SYNCH? */
107 int localflow; /* we handle flow control locally */
108 int restartany; /* if flow control enabled, restart on any character */
109 int localchars; /* we recognize interrupt/quit */
110 int donelclchars; /* the user has set "localchars" */
111 int donebinarytoggle; /* the user has put us in binary */
112 int dontlecho; /* do we suppress local echoing right now? */
113 int eof_pending = 0; /* we received a genuine EOF on input, send IAC-EOF */
114 int globalmode;
115
116 /* spin while waiting for authentication */
117 boolean_t scheduler_lockout_tty = B_FALSE;
118 int encrypt_flag = 0;
119 int forwardable_flag = 0;
120 int forward_flag = 0;
121 boolean_t wantencryption = B_FALSE;
122
123 char *prompt = 0;
124
125 cc_t escape;
126 cc_t rlogin;
127 boolean_t escape_valid = B_TRUE;
128 #ifdef KLUDGELINEMODE
129 cc_t echoc;
130 #endif
131
132 /*
133 * Telnet receiver states for fsm
134 */
135 #define TS_DATA 0
136 #define TS_IAC 1
137 #define TS_WILL 2
138 #define TS_WONT 3
139 #define TS_DO 4
140 #define TS_DONT 5
141 #define TS_CR 6
142 #define TS_SB 7 /* sub-option collection */
143 #define TS_SE 8 /* looking for sub-option end */
144
145 static int telrcv_state;
146 #ifdef OLD_ENVIRON
147 static unsigned char telopt_environ = TELOPT_NEW_ENVIRON;
148 #else
149 #define telopt_environ TELOPT_NEW_ENVIRON
150 #endif
151
152 jmp_buf toplevel = { 0 };
153 jmp_buf peerdied;
154
155 static int flushline;
156 int linemode;
157
158 int reqd_linemode = 0; /* Set if either new or old line mode in */
159 /* effect since before initial negotiations */
160
161 #ifdef KLUDGELINEMODE
162 int kludgelinemode = 1;
163 #endif
164
165 /*
166 * The following are some clocks used to decide how to interpret
167 * the relationship between various variables.
168 */
169
170 Clocks clocks;
171
172 #ifdef notdef
173 Modelist modelist[] = {
174 { "telnet command mode", COMMAND_LINE },
175 { "character-at-a-time mode", 0 },
176 { "character-at-a-time mode (local echo)", LOCAL_ECHO|LOCAL_CHARS },
177 { "line-by-line mode (remote echo)", LINE | LOCAL_CHARS },
178 { "line-by-line mode", LINE | LOCAL_ECHO | LOCAL_CHARS },
179 { "line-by-line mode (local echoing suppressed)", LINE | LOCAL_CHARS },
180 { "3270 mode", 0 },
181 };
182 #endif
183
184 static void willoption(int);
185 static void wontoption(int);
186 static void lm_will(unsigned char *, int);
187 static void lm_wont(unsigned char *, int);
188 static void lm_do(unsigned char *, int);
189 static void lm_dont(unsigned char *, int);
190 static void slc_init(void);
191 static void slc_import(int);
192 static void slc_export(void);
193 static void slc_start_reply(size_t);
194 static void slc_add_reply(unsigned char, unsigned char, cc_t);
195 static void slc_end_reply(void);
196 static void slc(unsigned char *, int);
197 static int slc_update(void);
198 static void env_opt(unsigned char *, int);
199 static void env_opt_start(void);
200 static void sendeof(void);
201 static int is_unique(register char *, register char **, register char **);
202
203 /*
204 * Initialize telnet environment.
205 */
206
207 int
init_telnet()208 init_telnet()
209 {
210 if (env_init() == 0)
211 return (0);
212
213 SB_CLEAR();
214 ClearArray(options);
215
216 connected = ISend = localflow = donebinarytoggle = 0;
217 restartany = -1;
218
219 SYNCHing = 0;
220
221 /* Don't change NetTrace */
222
223 escape = CONTROL(']');
224 rlogin = _POSIX_VDISABLE;
225 #ifdef KLUDGELINEMODE
226 echoc = CONTROL('E');
227 #endif
228
229 flushline = 1;
230 telrcv_state = TS_DATA;
231
232 return (1);
233 }
234
235
236 #ifdef notdef
237 #include <varargs.h>
238
239 /*VARARGS*/
240 static void
printring(va_alist)241 printring(va_alist)
242 va_dcl
243 {
244 va_list ap;
245 char buffer[100]; /* where things go */
246 char *ptr;
247 char *format;
248 char *string;
249 Ring *ring;
250 int i;
251
252 va_start(ap);
253
254 ring = va_arg(ap, Ring *);
255 format = va_arg(ap, char *);
256 ptr = buffer;
257
258 while ((i = *format++) != 0) {
259 if (i == '%') {
260 i = *format++;
261 switch (i) {
262 case 'c':
263 *ptr++ = va_arg(ap, int);
264 break;
265 case 's':
266 string = va_arg(ap, char *);
267 ring_supply_data(ring, buffer, ptr-buffer);
268 ring_supply_data(ring, string, strlen(string));
269 ptr = buffer;
270 break;
271 case 0:
272 ExitString("printring: trailing %%.\n",
273 EXIT_FAILURE);
274 /*NOTREACHED*/
275 default:
276 ExitString("printring: unknown format "
277 "character.\n", EXIT_FAILURE);
278 /*NOTREACHED*/
279 }
280 } else {
281 *ptr++ = i;
282 }
283 }
284 ring_supply_data(ring, buffer, ptr-buffer);
285 }
286 #endif
287
288 /*
289 * These routines are in charge of sending option negotiations
290 * to the other side.
291 *
292 * The basic idea is that we send the negotiation if either side
293 * is in disagreement as to what the current state should be.
294 */
295
296 void
send_do(c,init)297 send_do(c, init)
298 register int c, init;
299 {
300 if (init) {
301 if (((do_dont_resp[c] == 0) && my_state_is_do(c)) ||
302 my_want_state_is_do(c))
303 return;
304 set_my_want_state_do(c);
305 do_dont_resp[c]++;
306 }
307 NET2ADD(IAC, DO);
308 NETADD(c);
309 printoption("SENT", DO, c);
310 }
311
312 void
send_dont(c,init)313 send_dont(c, init)
314 register int c, init;
315 {
316 if (init) {
317 if (((do_dont_resp[c] == 0) && my_state_is_dont(c)) ||
318 my_want_state_is_dont(c))
319 return;
320 set_my_want_state_dont(c);
321 do_dont_resp[c]++;
322 }
323 NET2ADD(IAC, DONT);
324 NETADD(c);
325 printoption("SENT", DONT, c);
326 }
327
328 void
send_will(c,init)329 send_will(c, init)
330 register int c, init;
331 {
332 if (init) {
333 if (((will_wont_resp[c] == 0) && my_state_is_will(c)) ||
334 my_want_state_is_will(c))
335 return;
336 set_my_want_state_will(c);
337 will_wont_resp[c]++;
338 }
339 NET2ADD(IAC, WILL);
340 NETADD(c);
341 printoption("SENT", WILL, c);
342 }
343
344 void
send_wont(c,init)345 send_wont(c, init)
346 register int c, init;
347 {
348 if (init) {
349 if (((will_wont_resp[c] == 0) && my_state_is_wont(c)) ||
350 my_want_state_is_wont(c))
351 return;
352 set_my_want_state_wont(c);
353 will_wont_resp[c]++;
354 }
355 NET2ADD(IAC, WONT);
356 NETADD(c);
357 printoption("SENT", WONT, c);
358 }
359
360
361 static void
willoption(option)362 willoption(option)
363 int option;
364 {
365 int new_state_ok = 0;
366
367 if (do_dont_resp[option]) {
368 --do_dont_resp[option];
369 if (do_dont_resp[option] && my_state_is_do(option))
370 --do_dont_resp[option];
371 }
372
373 if ((do_dont_resp[option] == 0) && my_want_state_is_dont(option)) {
374
375 switch (option) {
376
377 case TELOPT_ECHO:
378 case TELOPT_SGA:
379 if (reqd_linemode && my_state_is_dont(option)) {
380 break;
381 }
382 /* FALLTHROUGH */
383 case TELOPT_BINARY:
384 settimer(modenegotiated);
385 /* FALLTHROUGH */
386 case TELOPT_STATUS:
387 case TELOPT_AUTHENTICATION:
388 /* FALLTHROUGH */
389 case TELOPT_ENCRYPT:
390 new_state_ok = 1;
391 break;
392
393 case TELOPT_TM:
394 if (flushout)
395 flushout = 0;
396 /*
397 * Special case for TM. If we get back a WILL,
398 * pretend we got back a WONT.
399 */
400 set_my_want_state_dont(option);
401 set_my_state_dont(option);
402 return; /* Never reply to TM will's/wont's */
403
404 case TELOPT_LINEMODE:
405 default:
406 break;
407 }
408
409 if (new_state_ok) {
410 set_my_want_state_do(option);
411 send_do(option, 0);
412 setconnmode(0); /* possibly set new tty mode */
413 } else {
414 do_dont_resp[option]++;
415 send_dont(option, 0);
416 }
417 }
418 set_my_state_do(option);
419 if (option == TELOPT_ENCRYPT)
420 encrypt_send_support();
421 }
422
423 static void
wontoption(option)424 wontoption(option)
425 int option;
426 {
427 if (do_dont_resp[option]) {
428 --do_dont_resp[option];
429 if (do_dont_resp[option] && my_state_is_dont(option))
430 --do_dont_resp[option];
431 }
432
433 if ((do_dont_resp[option] == 0) && my_want_state_is_do(option)) {
434
435 switch (option) {
436
437 #ifdef KLUDGELINEMODE
438 case TELOPT_SGA:
439 if (!kludgelinemode)
440 break;
441 /* FALLTHROUGH */
442 #endif
443 case TELOPT_ECHO:
444 settimer(modenegotiated);
445 break;
446
447 case TELOPT_TM:
448 if (flushout)
449 flushout = 0;
450 set_my_want_state_dont(option);
451 set_my_state_dont(option);
452 return; /* Never reply to TM will's/wont's */
453
454 default:
455 break;
456 }
457 set_my_want_state_dont(option);
458 if (my_state_is_do(option))
459 send_dont(option, 0);
460 setconnmode(0); /* Set new tty mode */
461 } else if (option == TELOPT_TM) {
462 /*
463 * Special case for TM.
464 */
465 if (flushout)
466 flushout = 0;
467 set_my_want_state_dont(option);
468 }
469 set_my_state_dont(option);
470 }
471
472 static void
dooption(option)473 dooption(option)
474 int option;
475 {
476 int new_state_ok = 0;
477
478 if (will_wont_resp[option]) {
479 --will_wont_resp[option];
480 if (will_wont_resp[option] && my_state_is_will(option))
481 --will_wont_resp[option];
482 }
483
484 if (will_wont_resp[option] == 0) {
485 if (my_want_state_is_wont(option)) {
486
487 switch (option) {
488
489 case TELOPT_TM:
490 /*
491 * Special case for TM. We send a WILL,
492 * but pretend we sent WONT.
493 */
494 send_will(option, 0);
495 set_my_want_state_wont(TELOPT_TM);
496 set_my_state_wont(TELOPT_TM);
497 return;
498
499 case TELOPT_BINARY: /* binary mode */
500 case TELOPT_NAWS: /* window size */
501 case TELOPT_TSPEED: /* terminal speed */
502 case TELOPT_LFLOW: /* local flow control */
503 case TELOPT_TTYPE: /* terminal type option */
504 case TELOPT_SGA: /* no big deal */
505 case TELOPT_ENCRYPT: /* encryption variable option */
506 new_state_ok = 1;
507 break;
508
509 case TELOPT_NEW_ENVIRON:
510 /* New environment variable option */
511 #ifdef OLD_ENVIRON
512 if (my_state_is_will(TELOPT_OLD_ENVIRON))
513 /* turn off the old */
514 send_wont(TELOPT_OLD_ENVIRON, 1);
515 goto env_common;
516 case TELOPT_OLD_ENVIRON:
517 /* Old environment variable option */
518 if (my_state_is_will(TELOPT_NEW_ENVIRON))
519 /* Don't enable if new one is in use! */
520 break;
521 env_common:
522 telopt_environ = option;
523 #endif
524 new_state_ok = 1;
525 break;
526
527 case TELOPT_AUTHENTICATION:
528 if (autologin)
529 new_state_ok = 1;
530 break;
531
532 case TELOPT_XDISPLOC: /* X Display location */
533 if (env_getvalue((unsigned char *)"DISPLAY"))
534 new_state_ok = 1;
535 break;
536
537 case TELOPT_LINEMODE:
538 #ifdef KLUDGELINEMODE
539 kludgelinemode = 0;
540 send_do(TELOPT_SGA, 1);
541 #endif
542 set_my_want_state_will(TELOPT_LINEMODE);
543 send_will(option, 0);
544 set_my_state_will(TELOPT_LINEMODE);
545 slc_init();
546 return;
547
548 case TELOPT_ECHO: /* We're never going to echo... */
549 default:
550 break;
551 }
552
553 if (new_state_ok) {
554 set_my_want_state_will(option);
555 send_will(option, 0);
556 setconnmode(0); /* Set new tty mode */
557 } else {
558 will_wont_resp[option]++;
559 send_wont(option, 0);
560 }
561 } else {
562 /*
563 * Handle options that need more things done after the
564 * other side has acknowledged the option.
565 */
566 switch (option) {
567 case TELOPT_LINEMODE:
568 #ifdef KLUDGELINEMODE
569 kludgelinemode = 0;
570 send_do(TELOPT_SGA, 1);
571 #endif
572 set_my_state_will(option);
573 slc_init();
574 send_do(TELOPT_SGA, 0);
575 return;
576 }
577 }
578 }
579 set_my_state_will(option);
580 }
581
582 static void
dontoption(option)583 dontoption(option)
584 int option;
585 {
586
587 if (will_wont_resp[option]) {
588 --will_wont_resp[option];
589 if (will_wont_resp[option] && my_state_is_wont(option))
590 --will_wont_resp[option];
591 }
592
593 if ((will_wont_resp[option] == 0) && my_want_state_is_will(option)) {
594 switch (option) {
595 case TELOPT_LINEMODE:
596 linemode = 0; /* put us back to the default state */
597 break;
598 #ifdef OLD_ENVIRON
599 case TELOPT_NEW_ENVIRON:
600 /*
601 * The new environ option wasn't recognized, try
602 * the old one.
603 */
604 send_will(TELOPT_OLD_ENVIRON, 1);
605 telopt_environ = TELOPT_OLD_ENVIRON;
606 break;
607 #endif
608 }
609 /* we always accept a DONT */
610 set_my_want_state_wont(option);
611 if (my_state_is_will(option))
612 send_wont(option, 0);
613 setconnmode(0); /* Set new tty mode */
614 }
615 set_my_state_wont(option);
616 }
617
618 /*
619 * Given a buffer returned by tgetent(), this routine will turn
620 * the pipe seperated list of names in the buffer into an array
621 * of pointers to null terminated names. We toss out any bad,
622 * duplicate, or verbose names (names with spaces).
623 */
624
625 static char *name_unknown = "UNKNOWN";
626 static char *unknown[] = { 0, 0 };
627
628 static char **
mklist(buf,name)629 mklist(buf, name)
630 char *buf, *name;
631 {
632 register int n;
633 register char c, *cp, **argvp, *cp2, **argv, **avt;
634
635 if (name) {
636 if (strlen(name) > 40u) {
637 name = 0;
638 unknown[0] = name_unknown;
639 } else {
640 unknown[0] = name;
641 upcase(name);
642 }
643 } else
644 unknown[0] = name_unknown;
645 /*
646 * Count up the number of names.
647 */
648 for (n = 1, cp = buf; *cp && *cp != ':'; cp++) {
649 if (*cp == '|')
650 n++;
651 }
652 /*
653 * Allocate an array to put the name pointers into
654 */
655 argv = malloc((n+3)*sizeof (char *));
656 if (argv == 0)
657 return (unknown);
658
659 /*
660 * Fill up the array of pointers to names.
661 */
662 *argv = 0;
663 argvp = argv+1;
664 n = 0;
665 for (cp = cp2 = buf; (c = *cp) != NULL; cp++) {
666 if (c == '|' || c == ':') {
667 *cp++ = '\0';
668 /*
669 * Skip entries that have spaces or are over 40
670 * characters long. If this is our environment
671 * name, then put it up front. Otherwise, as
672 * long as this is not a duplicate name (case
673 * insensitive) add it to the list.
674 */
675 if (n || (cp - cp2 > 41))
676 /* EMPTY */;
677 else if (name && (strncasecmp(name, cp2, cp-cp2) == 0))
678 *argv = cp2;
679 else if (is_unique(cp2, argv+1, argvp))
680 *argvp++ = cp2;
681 if (c == ':')
682 break;
683 /*
684 * Skip multiple delimiters. Reset cp2 to
685 * the beginning of the next name. Reset n,
686 * the flag for names with spaces.
687 */
688 while ((c = *cp) == '|')
689 cp++;
690 cp2 = cp;
691 n = 0;
692 }
693 /*
694 * Skip entries with spaces or non-ascii values.
695 * Convert lower case letters to upper case.
696 */
697 if ((c == ' ') || !isascii(c))
698 n = 1;
699 else if (islower(c))
700 *cp = toupper(c);
701 }
702
703 /*
704 * Check for an old V6 2 character name. If the second
705 * name points to the beginning of the buffer, and is
706 * only 2 characters long, move it to the end of the array.
707 */
708 if ((argv[1] == buf) && (strlen(argv[1]) == 2)) {
709 --argvp;
710 for (avt = &argv[1]; avt < argvp; avt++)
711 *avt = *(avt+1);
712 *argvp++ = buf;
713 }
714
715 /*
716 * Duplicate last name, for TTYPE option, and null
717 * terminate the array. If we didn't find a match on
718 * our terminal name, put that name at the beginning.
719 */
720 cp = *(argvp-1);
721 *argvp++ = cp;
722 *argvp = 0;
723
724 if (*argv == 0) {
725 if (name)
726 *argv = name;
727 else {
728 --argvp;
729 for (avt = argv; avt < argvp; avt++)
730 *avt = *(avt+1);
731 }
732 }
733 if (*argv)
734 return (argv);
735 else
736 return (unknown);
737 }
738
739 static int
is_unique(name,as,ae)740 is_unique(name, as, ae)
741 register char *name, **as, **ae;
742 {
743 register char **ap;
744 register int n;
745
746 n = strlen(name) + 1;
747 for (ap = as; ap < ae; ap++)
748 if (strncasecmp(*ap, name, n) == 0)
749 return (0);
750 return (1);
751 }
752
753 #define termbuf ttytype
754 extern char ttytype[];
755
756 int resettermname = 1;
757
758 static char *
gettermname(void)759 gettermname(void)
760 {
761 char *tname;
762 static char **tnamep = 0;
763 static char **next;
764 int err;
765
766 if (resettermname) {
767 resettermname = 0;
768 if (tnamep && tnamep != unknown)
769 free(tnamep);
770 tname = (char *)env_getvalue((unsigned char *)"TERM");
771 if ((tname != NULL) && (setupterm(tname, 1, &err) == 0)) {
772 tnamep = mklist(termbuf, tname);
773 } else {
774 if (tname && (strlen(tname) <= 40u)) {
775 unknown[0] = tname;
776 upcase(tname);
777 } else
778 unknown[0] = name_unknown;
779 tnamep = unknown;
780 }
781 next = tnamep;
782 }
783 if (*next == 0)
784 next = tnamep;
785 return (*next++);
786 }
787 /*
788 * suboption()
789 *
790 * Look at the sub-option buffer, and try to be helpful to the other
791 * side.
792 *
793 * Currently we recognize:
794 *
795 * Terminal type, send request.
796 * Terminal speed (send request).
797 * Local flow control (is request).
798 * Linemode
799 */
800
801 static void
suboption()802 suboption()
803 {
804 unsigned char subchar;
805
806 printsub('<', subbuffer, SB_LEN()+2);
807 switch (subchar = SB_GET()) {
808 case TELOPT_TTYPE:
809 if (my_want_state_is_wont(TELOPT_TTYPE))
810 return;
811 if (SB_EOF() || SB_GET() != TELQUAL_SEND) {
812 return;
813 } else {
814 char *name;
815 unsigned char temp[50];
816 int len, bytes;
817
818 name = gettermname();
819 len = strlen(name) + 4 + 2;
820 bytes = snprintf((char *)temp, sizeof (temp),
821 "%c%c%c%c%s%c%c", IAC, SB,
822 TELOPT_TTYPE, TELQUAL_IS, name, IAC, SE);
823 if ((len < NETROOM()) && (bytes < sizeof (temp))) {
824 ring_supply_data(&netoring, temp, len);
825 printsub('>', &temp[2], len-2);
826 } else {
827 ExitString("No room in buffer for "
828 "terminal type.\n", EXIT_FAILURE);
829 /*NOTREACHED*/
830 }
831 }
832 break;
833 case TELOPT_TSPEED:
834 if (my_want_state_is_wont(TELOPT_TSPEED))
835 return;
836 if (SB_EOF())
837 return;
838 if (SB_GET() == TELQUAL_SEND) {
839 int ospeed, ispeed;
840 unsigned char temp[50];
841 int len, bytes;
842
843 TerminalSpeeds(&ispeed, &ospeed);
844
845 bytes = snprintf((char *)temp, sizeof (temp),
846 "%c%c%c%c%d,%d%c%c", IAC, SB,
847 TELOPT_TSPEED, TELQUAL_IS, ospeed, ispeed, IAC, SE);
848 len = strlen((char *)temp+4) + 4; /* temp[3] is 0 ... */
849
850 if ((len < NETROOM()) && (bytes < sizeof (temp))) {
851 ring_supply_data(&netoring, temp, len);
852 printsub('>', temp+2, len - 2);
853 }
854 else
855 (void) printf(
856 "telnet: not enough room in buffer "
857 "for terminal speed option reply\n");
858 }
859 break;
860 case TELOPT_LFLOW:
861 if (my_want_state_is_wont(TELOPT_LFLOW))
862 return;
863 if (SB_EOF())
864 return;
865 switch (SB_GET()) {
866 case LFLOW_RESTART_ANY:
867 restartany = 1;
868 break;
869 case LFLOW_RESTART_XON:
870 restartany = 0;
871 break;
872 case LFLOW_ON:
873 localflow = 1;
874 break;
875 case LFLOW_OFF:
876 localflow = 0;
877 break;
878 default:
879 return;
880 }
881 setcommandmode();
882 setconnmode(0);
883 break;
884
885 case TELOPT_LINEMODE:
886 if (my_want_state_is_wont(TELOPT_LINEMODE))
887 return;
888 if (SB_EOF())
889 return;
890 switch (SB_GET()) {
891 case WILL:
892 lm_will(subpointer, SB_LEN());
893 break;
894 case WONT:
895 lm_wont(subpointer, SB_LEN());
896 break;
897 case DO:
898 lm_do(subpointer, SB_LEN());
899 break;
900 case DONT:
901 lm_dont(subpointer, SB_LEN());
902 break;
903 case LM_SLC:
904 slc(subpointer, SB_LEN());
905 break;
906 case LM_MODE:
907 lm_mode(subpointer, SB_LEN(), 0);
908 break;
909 default:
910 break;
911 }
912 break;
913
914 #ifdef OLD_ENVIRON
915 case TELOPT_OLD_ENVIRON:
916 #endif
917 case TELOPT_NEW_ENVIRON:
918 if (SB_EOF())
919 return;
920 switch (SB_PEEK()) {
921 case TELQUAL_IS:
922 case TELQUAL_INFO:
923 if (my_want_state_is_dont(subchar))
924 return;
925 break;
926 case TELQUAL_SEND:
927 if (my_want_state_is_wont(subchar)) {
928 return;
929 }
930 break;
931 default:
932 return;
933 }
934 env_opt(subpointer, SB_LEN());
935 break;
936
937 case TELOPT_XDISPLOC:
938 if (my_want_state_is_wont(TELOPT_XDISPLOC))
939 return;
940 if (SB_EOF())
941 return;
942 if (SB_GET() == TELQUAL_SEND) {
943 unsigned char temp[50], *dp;
944 int len, bytes;
945
946 if ((dp = env_getvalue((unsigned char *)"DISPLAY")) ==
947 NULL) {
948 /*
949 * Something happened, we no longer have a
950 * DISPLAY variable. So, turn off the option.
951 */
952 send_wont(TELOPT_XDISPLOC, 1);
953 break;
954 }
955 bytes = snprintf((char *)temp, sizeof (temp),
956 "%c%c%c%c%s%c%c", IAC, SB,
957 TELOPT_XDISPLOC, TELQUAL_IS, dp, IAC, SE);
958 len = strlen((char *)temp+4) + 4; /* temp[3] is 0 ... */
959
960 if ((len < NETROOM()) && (bytes < sizeof (temp))) {
961 ring_supply_data(&netoring, temp, len);
962 printsub('>', temp+2, len - 2);
963 }
964 else
965 (void) printf(
966 "telnet: not enough room in buffer"
967 " for display location option reply\n");
968 }
969 break;
970
971 case TELOPT_AUTHENTICATION: {
972 if (!autologin)
973 break;
974 if (SB_EOF())
975 return;
976 switch (SB_GET()) {
977 case TELQUAL_SEND:
978 if (my_want_state_is_wont(TELOPT_AUTHENTICATION))
979 return;
980 auth_send(subpointer, SB_LEN());
981 break;
982 case TELQUAL_REPLY:
983 if (my_want_state_is_wont(TELOPT_AUTHENTICATION))
984 return;
985 auth_reply(subpointer, SB_LEN());
986 break;
987 }
988 }
989 break;
990
991 case TELOPT_ENCRYPT:
992 if (SB_EOF())
993 return;
994 switch (SB_GET()) {
995 case ENCRYPT_START:
996 if (my_want_state_is_dont(TELOPT_ENCRYPT))
997 return;
998 encrypt_start(subpointer, SB_LEN());
999 break;
1000 case ENCRYPT_END:
1001 if (my_want_state_is_dont(TELOPT_ENCRYPT))
1002 return;
1003 encrypt_end();
1004 break;
1005 case ENCRYPT_SUPPORT:
1006 if (my_want_state_is_wont(TELOPT_ENCRYPT))
1007 return;
1008 encrypt_support(subpointer, SB_LEN());
1009 break;
1010 case ENCRYPT_REQSTART:
1011 if (my_want_state_is_wont(TELOPT_ENCRYPT))
1012 return;
1013 encrypt_request_start(subpointer, SB_LEN());
1014 break;
1015 case ENCRYPT_REQEND:
1016 if (my_want_state_is_wont(TELOPT_ENCRYPT))
1017 return;
1018 /*
1019 * We can always send an REQEND so that we cannot
1020 * get stuck encrypting. We should only get this
1021 * if we have been able to get in the correct mode
1022 * anyhow.
1023 */
1024 encrypt_request_end();
1025 break;
1026 case ENCRYPT_IS:
1027 if (my_want_state_is_dont(TELOPT_ENCRYPT))
1028 return;
1029 encrypt_is(subpointer, SB_LEN());
1030 break;
1031 case ENCRYPT_REPLY:
1032 if (my_want_state_is_wont(TELOPT_ENCRYPT))
1033 return;
1034 encrypt_reply(subpointer, SB_LEN());
1035 break;
1036 case ENCRYPT_ENC_KEYID:
1037 if (my_want_state_is_dont(TELOPT_ENCRYPT))
1038 return;
1039 encrypt_enc_keyid(subpointer, SB_LEN());
1040 break;
1041 case ENCRYPT_DEC_KEYID:
1042 if (my_want_state_is_wont(TELOPT_ENCRYPT))
1043 return;
1044 encrypt_dec_keyid(subpointer, SB_LEN());
1045 break;
1046 default:
1047 break;
1048 }
1049 break;
1050 default:
1051 break;
1052 }
1053 }
1054
1055 static unsigned char str_lm[] = { IAC, SB, TELOPT_LINEMODE, 0, 0, IAC, SE };
1056
1057 static void
lm_will(cmd,len)1058 lm_will(cmd, len)
1059 unsigned char *cmd;
1060 int len;
1061 {
1062 if (len < 1) {
1063 /* Should not happen... */
1064 (void) printf(
1065 "telnet: command missing from linemode WILL request\n");
1066 return;
1067 }
1068 switch (cmd[0]) {
1069 case LM_FORWARDMASK: /* We shouldn't ever get this... */
1070 default:
1071 str_lm[3] = DONT;
1072 str_lm[4] = cmd[0];
1073 if (NETROOM() > sizeof (str_lm)) {
1074 ring_supply_data(&netoring, str_lm, sizeof (str_lm));
1075 printsub('>', &str_lm[2], sizeof (str_lm)-2);
1076 }
1077 else
1078 (void) printf("telnet: not enough room in buffer for"
1079 "reply to linemode WILL request\n");
1080 break;
1081 }
1082 }
1083
1084 static void
lm_wont(cmd,len)1085 lm_wont(cmd, len)
1086 unsigned char *cmd;
1087 int len;
1088 {
1089 if (len < 1) {
1090 /* Should not happen... */
1091 (void) printf(
1092 "telnet: command missing from linemode WONT request\n");
1093 return;
1094 }
1095 switch (cmd[0]) {
1096 case LM_FORWARDMASK: /* We shouldn't ever get this... */
1097 default:
1098 /* We are always DONT, so don't respond */
1099 return;
1100 }
1101 }
1102
1103 static void
lm_do(cmd,len)1104 lm_do(cmd, len)
1105 unsigned char *cmd;
1106 int len;
1107 {
1108 if (len < 1) {
1109 /* Should not happen... */
1110 (void) printf(
1111 "telnet: command missing from linemode DO request\n");
1112 return;
1113 }
1114 switch (cmd[0]) {
1115 case LM_FORWARDMASK:
1116 default:
1117 str_lm[3] = WONT;
1118 str_lm[4] = cmd[0];
1119 if (NETROOM() > sizeof (str_lm)) {
1120 ring_supply_data(&netoring, str_lm, sizeof (str_lm));
1121 printsub('>', &str_lm[2], sizeof (str_lm)-2);
1122 }
1123 else
1124 (void) printf("telnet: not enough room in buffer for"
1125 "reply to linemode DO request\n");
1126 break;
1127 }
1128 }
1129
1130 static void
lm_dont(cmd,len)1131 lm_dont(cmd, len)
1132 unsigned char *cmd;
1133 int len;
1134 {
1135 if (len < 1) {
1136 /* Should not happen... */
1137 (void) printf(
1138 "telnet: command missing from linemode DONT request\n");
1139 return;
1140 }
1141 switch (cmd[0]) {
1142 case LM_FORWARDMASK:
1143 default:
1144 /* we are always WONT, so don't respond */
1145 break;
1146 }
1147 }
1148
1149 static unsigned char str_lm_mode[] = {
1150 IAC, SB, TELOPT_LINEMODE, LM_MODE, 0, IAC, SE
1151 };
1152
1153 void
lm_mode(cmd,len,init)1154 lm_mode(cmd, len, init)
1155 unsigned char *cmd;
1156 int len, init;
1157 {
1158 if (len != 1)
1159 return;
1160 if ((linemode&MODE_MASK&~MODE_ACK) == *cmd)
1161 return;
1162 linemode = *cmd&(MODE_MASK&~MODE_ACK);
1163 str_lm_mode[4] = linemode;
1164 if (!init)
1165 str_lm_mode[4] |= MODE_ACK;
1166 if (NETROOM() > sizeof (str_lm_mode)) {
1167 ring_supply_data(&netoring, str_lm_mode, sizeof (str_lm_mode));
1168 printsub('>', &str_lm_mode[2], sizeof (str_lm_mode)-2);
1169 }
1170 else
1171 (void) printf("telnet: not enough room in buffer for"
1172 "reply to linemode request\n");
1173 setconnmode(0); /* set changed mode */
1174 }
1175
1176
1177
1178 /*
1179 * slc()
1180 * Handle special character suboption of LINEMODE.
1181 */
1182
1183 static struct spc {
1184 cc_t val;
1185 cc_t *valp;
1186 char flags; /* Current flags & level */
1187 char mylevel; /* Maximum level & flags */
1188 } spc_data[NSLC+1];
1189
1190 #define SLC_IMPORT 0
1191 #define SLC_EXPORT 1
1192 #define SLC_RVALUE 2
1193 static int slc_mode = SLC_EXPORT;
1194
1195 static void
slc_init()1196 slc_init()
1197 {
1198 register struct spc *spcp;
1199
1200 localchars = 1;
1201 for (spcp = spc_data; spcp < &spc_data[NSLC+1]; spcp++) {
1202 spcp->val = 0;
1203 spcp->valp = 0;
1204 spcp->flags = spcp->mylevel = SLC_NOSUPPORT;
1205 }
1206
1207 #define initfunc(func, flags) { \
1208 spcp = &spc_data[func]; \
1209 if (spcp->valp = tcval(func)) { \
1210 spcp->val = *spcp->valp; \
1211 spcp->mylevel = SLC_VARIABLE|(flags);\
1212 } else { \
1213 spcp->val = 0; \
1214 spcp->mylevel = SLC_DEFAULT; \
1215 } \
1216 }
1217
1218 initfunc(SLC_SYNCH, 0);
1219 /* No BRK */
1220 initfunc(SLC_AO, 0);
1221 initfunc(SLC_AYT, 0);
1222 /* No EOR */
1223 initfunc(SLC_ABORT, SLC_FLUSHIN|SLC_FLUSHOUT);
1224 initfunc(SLC_EOF, 0);
1225 initfunc(SLC_SUSP, SLC_FLUSHIN);
1226 initfunc(SLC_EC, 0);
1227 initfunc(SLC_EL, 0);
1228 initfunc(SLC_EW, 0);
1229 initfunc(SLC_RP, 0);
1230 initfunc(SLC_LNEXT, 0);
1231 initfunc(SLC_XON, 0);
1232 initfunc(SLC_XOFF, 0);
1233 initfunc(SLC_FORW1, 0);
1234 #ifdef USE_TERMIO
1235 initfunc(SLC_FORW2, 0);
1236 /* No FORW2 */
1237 #endif
1238
1239 initfunc(SLC_IP, SLC_FLUSHIN|SLC_FLUSHOUT);
1240 #undef initfunc
1241
1242 if (slc_mode == SLC_EXPORT)
1243 slc_export();
1244 else
1245 slc_import(1);
1246
1247 }
1248
1249 void
slcstate()1250 slcstate()
1251 {
1252 (void) printf("Special characters are %s values\n",
1253 slc_mode == SLC_IMPORT ? "remote default" :
1254 slc_mode == SLC_EXPORT ? "local" :
1255 "remote");
1256 }
1257
1258 void
slc_mode_export()1259 slc_mode_export()
1260 {
1261 slc_mode = SLC_EXPORT;
1262 if (my_state_is_will(TELOPT_LINEMODE))
1263 slc_export();
1264 }
1265
1266 void
slc_mode_import(def)1267 slc_mode_import(def)
1268 int def;
1269 {
1270 slc_mode = def ? SLC_IMPORT : SLC_RVALUE;
1271 if (my_state_is_will(TELOPT_LINEMODE))
1272 slc_import(def);
1273 }
1274
1275 static unsigned char slc_import_val[] = {
1276 IAC, SB, TELOPT_LINEMODE, LM_SLC, 0, SLC_VARIABLE, 0, IAC, SE
1277 };
1278 static unsigned char slc_import_def[] = {
1279 IAC, SB, TELOPT_LINEMODE, LM_SLC, 0, SLC_DEFAULT, 0, IAC, SE
1280 };
1281
1282 static void
slc_import(def)1283 slc_import(def)
1284 int def;
1285 {
1286 if (NETROOM() > sizeof (slc_import_val)) {
1287 if (def) {
1288 ring_supply_data(&netoring, slc_import_def,
1289 sizeof (slc_import_def));
1290 printsub('>', &slc_import_def[2],
1291 sizeof (slc_import_def)-2);
1292 } else {
1293 ring_supply_data(&netoring, slc_import_val,
1294 sizeof (slc_import_val));
1295 printsub('>', &slc_import_val[2],
1296 sizeof (slc_import_val)-2);
1297 }
1298 }
1299 else
1300 (void) printf(
1301 "telnet: not enough room in buffer for slc import"
1302 " request\n");
1303 }
1304
1305 static uchar_t *slc_reply = NULL;
1306 static uchar_t *slc_replyp = NULL;
1307 /*
1308 * The SLC reply consists of: IAC, SB, TELOPT_LINEMODE, LM_SLC,
1309 * SLC triplets[], IAC, SE. i.e. it has a 'wrapper' of 6 control characters.
1310 */
1311 #define SLC_WRAPPER_SIZE 6
1312
1313 static void
slc_export()1314 slc_export()
1315 {
1316 register struct spc *spcp;
1317
1318 TerminalDefaultChars();
1319
1320 slc_start_reply(NSLC * 3); /* 3 bytes needed per triplet */
1321 for (spcp = &spc_data[1]; spcp < &spc_data[NSLC+1]; spcp++) {
1322 if (spcp->mylevel != SLC_NOSUPPORT) {
1323 if (spcp->val == (cc_t)(_POSIX_VDISABLE))
1324 spcp->flags = SLC_NOSUPPORT;
1325 else
1326 spcp->flags = spcp->mylevel;
1327 if (spcp->valp)
1328 spcp->val = *spcp->valp;
1329 slc_add_reply(spcp - spc_data, spcp->flags, spcp->val);
1330 }
1331 }
1332 slc_end_reply();
1333 (void) slc_update();
1334 setconnmode(1); /* Make sure the character values are set */
1335 }
1336
1337 static void
slc(cp,len)1338 slc(cp, len)
1339 register unsigned char *cp;
1340 int len;
1341 {
1342 register struct spc *spcp;
1343 register int func, level;
1344
1345 slc_start_reply(len);
1346
1347 for (; len >= 3; len -= 3, cp += 3) {
1348
1349 func = cp[SLC_FUNC];
1350
1351 if (func == 0) {
1352 /*
1353 * Client side: always ignore 0 function.
1354 */
1355 continue;
1356 }
1357 if (func > NSLC) {
1358 if ((cp[SLC_FLAGS] & SLC_LEVELBITS) != SLC_NOSUPPORT)
1359 slc_add_reply(func, SLC_NOSUPPORT, 0);
1360 continue;
1361 }
1362
1363 spcp = &spc_data[func];
1364
1365 level = cp[SLC_FLAGS]&(SLC_LEVELBITS|SLC_ACK);
1366
1367 if ((cp[SLC_VALUE] == (unsigned char)spcp->val) &&
1368 ((level&SLC_LEVELBITS) == (spcp->flags&SLC_LEVELBITS))) {
1369 continue;
1370 }
1371
1372 if (level == (SLC_DEFAULT|SLC_ACK)) {
1373 /*
1374 * This is an error condition, the SLC_ACK
1375 * bit should never be set for the SLC_DEFAULT
1376 * level. Our best guess to recover is to
1377 * ignore the SLC_ACK bit.
1378 */
1379 cp[SLC_FLAGS] &= ~SLC_ACK;
1380 }
1381
1382 if (level == ((spcp->flags&SLC_LEVELBITS)|SLC_ACK)) {
1383 spcp->val = (cc_t)cp[SLC_VALUE];
1384 spcp->flags = cp[SLC_FLAGS]; /* include SLC_ACK */
1385 continue;
1386 }
1387
1388 level &= ~SLC_ACK;
1389
1390 if (level <= (spcp->mylevel&SLC_LEVELBITS)) {
1391 spcp->flags = cp[SLC_FLAGS]|SLC_ACK;
1392 spcp->val = (cc_t)cp[SLC_VALUE];
1393 }
1394 if (level == SLC_DEFAULT) {
1395 if ((spcp->mylevel&SLC_LEVELBITS) != SLC_DEFAULT)
1396 spcp->flags = spcp->mylevel;
1397 else
1398 spcp->flags = SLC_NOSUPPORT;
1399 }
1400 slc_add_reply(func, spcp->flags, spcp->val);
1401 }
1402 slc_end_reply();
1403 if (slc_update())
1404 setconnmode(1); /* set the new character values */
1405 }
1406
1407 void
slc_check()1408 slc_check()
1409 {
1410 register struct spc *spcp;
1411
1412 slc_start_reply(NSLC * 3); /* 3 bytes needed per triplet */
1413 for (spcp = &spc_data[1]; spcp < &spc_data[NSLC+1]; spcp++) {
1414 if (spcp->valp && spcp->val != *spcp->valp) {
1415 spcp->val = *spcp->valp;
1416 if (spcp->val == (cc_t)(_POSIX_VDISABLE))
1417 spcp->flags = SLC_NOSUPPORT;
1418 else
1419 spcp->flags = spcp->mylevel;
1420 slc_add_reply(spcp - spc_data, spcp->flags, spcp->val);
1421 }
1422 }
1423 slc_end_reply();
1424 setconnmode(1);
1425 }
1426
1427 static void
slc_start_reply(size_t len)1428 slc_start_reply(size_t len)
1429 {
1430 /*
1431 * SLC triplets may contain escaped characters, allow for
1432 * worst case by allocating 2 bytes for every character.
1433 */
1434 slc_reply = realloc(slc_reply, (len * 2) + SLC_WRAPPER_SIZE);
1435 if (slc_reply == NULL) {
1436 fprintf(stderr, "telnet: error allocating SLC reply memory\n");
1437 return;
1438 }
1439 slc_replyp = slc_reply;
1440 *slc_replyp++ = IAC;
1441 *slc_replyp++ = SB;
1442 *slc_replyp++ = TELOPT_LINEMODE;
1443 *slc_replyp++ = LM_SLC;
1444 }
1445
1446 static void
slc_add_reply(unsigned char func,unsigned char flags,cc_t value)1447 slc_add_reply(unsigned char func, unsigned char flags, cc_t value)
1448 {
1449 if ((*slc_replyp++ = func) == IAC)
1450 *slc_replyp++ = IAC;
1451 if ((*slc_replyp++ = flags) == IAC)
1452 *slc_replyp++ = IAC;
1453 if ((*slc_replyp++ = (unsigned char)value) == IAC)
1454 *slc_replyp++ = IAC;
1455 }
1456
1457 static void
slc_end_reply()1458 slc_end_reply()
1459 {
1460 register int len;
1461
1462 *slc_replyp++ = IAC;
1463 *slc_replyp++ = SE;
1464 len = slc_replyp - slc_reply;
1465 if (len <= SLC_WRAPPER_SIZE)
1466 return;
1467 if (NETROOM() > len) {
1468 ring_supply_data(&netoring, slc_reply, slc_replyp - slc_reply);
1469 printsub('>', &slc_reply[2], slc_replyp - slc_reply - 2);
1470 }
1471 else
1472 (void) printf("telnet: not enough room in buffer for slc end "
1473 "reply\n");
1474 }
1475
1476 static int
slc_update()1477 slc_update()
1478 {
1479 register struct spc *spcp;
1480 int need_update = 0;
1481
1482 for (spcp = &spc_data[1]; spcp < &spc_data[NSLC+1]; spcp++) {
1483 if (!(spcp->flags&SLC_ACK))
1484 continue;
1485 spcp->flags &= ~SLC_ACK;
1486 if (spcp->valp && (*spcp->valp != spcp->val)) {
1487 *spcp->valp = spcp->val;
1488 need_update = 1;
1489 }
1490 }
1491 return (need_update);
1492 }
1493
1494 #ifdef OLD_ENVIRON
1495 #ifdef ENV_HACK
1496 /*
1497 * Earlier version of telnet/telnetd from the BSD code had
1498 * the definitions of VALUE and VAR reversed. To ensure
1499 * maximum interoperability, we assume that the server is
1500 * an older BSD server, until proven otherwise. The newer
1501 * BSD servers should be able to handle either definition,
1502 * so it is better to use the wrong values if we don't
1503 * know what type of server it is.
1504 */
1505 int env_auto = 1;
1506 int old_env_var = OLD_ENV_VAR;
1507 int old_env_value = OLD_ENV_VALUE;
1508 #else
1509 #define old_env_var OLD_ENV_VAR
1510 #define old_env_value OLD_ENV_VALUE
1511 #endif
1512 #endif
1513
1514 static void
env_opt(buf,len)1515 env_opt(buf, len)
1516 register unsigned char *buf;
1517 register int len;
1518 {
1519 register unsigned char *ep = 0, *epc = 0;
1520 register int i;
1521
1522 switch (buf[0]&0xff) {
1523 case TELQUAL_SEND:
1524 env_opt_start();
1525 if (len == 1) {
1526 env_opt_add(NULL);
1527 } else for (i = 1; i < len; i++) {
1528 switch (buf[i]&0xff) {
1529 #ifdef OLD_ENVIRON
1530 case OLD_ENV_VAR:
1531 #ifdef ENV_HACK
1532 if (telopt_environ == TELOPT_OLD_ENVIRON &&
1533 env_auto) {
1534 /* Server has the same definitions */
1535 old_env_var = OLD_ENV_VAR;
1536 old_env_value = OLD_ENV_VALUE;
1537 }
1538 /* FALLTHROUGH */
1539 #endif
1540 case OLD_ENV_VALUE:
1541 /*
1542 * Although OLD_ENV_VALUE is not legal, we will
1543 * still recognize it, just in case it is an
1544 * old server that has VAR & VALUE mixed up...
1545 */
1546 /* FALLTHROUGH */
1547 #else
1548 case NEW_ENV_VAR:
1549 #endif
1550 case ENV_USERVAR:
1551 if (ep) {
1552 *epc = 0;
1553 env_opt_add(ep);
1554 }
1555 ep = epc = &buf[i+1];
1556 break;
1557 case ENV_ESC:
1558 i++;
1559 /*FALLTHROUGH*/
1560 default:
1561 if (epc)
1562 *epc++ = buf[i];
1563 break;
1564 }
1565 }
1566 if (ep) {
1567 *epc = 0;
1568 env_opt_add(ep);
1569 }
1570 env_opt_end(1);
1571 break;
1572
1573 case TELQUAL_IS:
1574 case TELQUAL_INFO:
1575 /* Ignore for now. We shouldn't get it anyway. */
1576 break;
1577
1578 default:
1579 break;
1580 }
1581 }
1582
1583 static unsigned char *opt_reply;
1584 static unsigned char *opt_replyp;
1585 static unsigned char *opt_replyend;
1586 #define OPT_REPLY_INITIAL_SIZE 256
1587 /*
1588 * The opt reply consists of: IAC, SB, telopt_environ, TELQUAL_IS,
1589 * value, IAC, SE. i.e. it has a 'wrapper' of 6 control characters.
1590 */
1591 #define OPT_WRAPPER_SIZE 6
1592
1593 static void
env_opt_start()1594 env_opt_start()
1595 {
1596 opt_reply = realloc(opt_reply, OPT_REPLY_INITIAL_SIZE);
1597 if (opt_reply == NULL) {
1598 (void) printf(
1599 "telnet: error allocating environment option memory\n");
1600 opt_reply = opt_replyp = opt_replyend = NULL;
1601 return;
1602 }
1603 opt_replyp = opt_reply;
1604 opt_replyend = opt_reply + OPT_REPLY_INITIAL_SIZE;
1605 *opt_replyp++ = IAC;
1606 *opt_replyp++ = SB;
1607 *opt_replyp++ = telopt_environ;
1608 *opt_replyp++ = TELQUAL_IS;
1609 }
1610
1611 void
env_opt_start_info()1612 env_opt_start_info()
1613 {
1614 env_opt_start();
1615 if (opt_replyp)
1616 opt_replyp[-1] = TELQUAL_INFO;
1617 }
1618
1619 void
env_opt_add(ep)1620 env_opt_add(ep)
1621 register unsigned char *ep;
1622 {
1623 register unsigned char *vp, c;
1624 int opt_reply_size;
1625 int opt_reply_used;
1626
1627 if (opt_reply == NULL) /* XXX */
1628 return; /* XXX */
1629
1630 if (ep == NULL || *ep == '\0') {
1631 /* Send user defined variables first. */
1632 (void) env_default(1, 0);
1633 while (ep = env_default(0, 0))
1634 env_opt_add(ep);
1635
1636 /* Now add the list of well know variables. */
1637 (void) env_default(1, 1);
1638 while (ep = env_default(0, 1))
1639 env_opt_add(ep);
1640 return;
1641 }
1642 vp = env_getvalue(ep);
1643
1644 /*
1645 * Calculate space required for opt_reply and allocate more if required.
1646 * Assume worst case that every character is escaped, so needs 2 bytes.
1647 */
1648 opt_reply_used = opt_replyp - opt_reply; /* existing contents */
1649 opt_reply_size = opt_reply_used + OPT_WRAPPER_SIZE +
1650 (2 * (strlen((char *)ep))) +
1651 (vp == NULL ? 0 : (2 * strlen((char *)vp)));
1652
1653 if (opt_reply_size > (opt_replyend - opt_reply)) {
1654 opt_reply = realloc(opt_reply, opt_reply_size);
1655 if (opt_reply == NULL) {
1656 (void) printf(
1657 "telnet: can't allocate environment option "
1658 "reply\n");
1659 opt_reply = opt_replyp = opt_replyend = NULL;
1660 return;
1661 }
1662 opt_replyp = opt_reply + opt_reply_used;
1663 opt_replyend = opt_reply + opt_reply_size;
1664 }
1665
1666 if (opt_welldefined((char *)ep))
1667 #ifdef OLD_ENVIRON
1668 if (telopt_environ == TELOPT_OLD_ENVIRON)
1669 *opt_replyp++ = old_env_var;
1670 else
1671 #endif
1672 *opt_replyp++ = NEW_ENV_VAR;
1673 else
1674 *opt_replyp++ = ENV_USERVAR;
1675 for (;;) {
1676 while ((c = *ep++) != NULL) {
1677 switch (c&0xff) {
1678 case IAC:
1679 *opt_replyp++ = IAC;
1680 break;
1681 case NEW_ENV_VAR:
1682 case NEW_ENV_VALUE:
1683 case ENV_ESC:
1684 case ENV_USERVAR:
1685 *opt_replyp++ = ENV_ESC;
1686 break;
1687 }
1688 *opt_replyp++ = c;
1689 }
1690 if ((ep = vp) != NULL) {
1691 #ifdef OLD_ENVIRON
1692 if (telopt_environ == TELOPT_OLD_ENVIRON)
1693 *opt_replyp++ = old_env_value;
1694 else
1695 #endif
1696 *opt_replyp++ = NEW_ENV_VALUE;
1697 vp = NULL;
1698 } else
1699 break;
1700 }
1701 }
1702
1703 int
opt_welldefined(ep)1704 opt_welldefined(ep)
1705 char *ep;
1706 {
1707 if ((strcmp(ep, "USER") == 0) ||
1708 (strcmp(ep, "DISPLAY") == 0) ||
1709 (strcmp(ep, "PRINTER") == 0) ||
1710 (strcmp(ep, "SYSTEMTYPE") == 0) ||
1711 (strcmp(ep, "JOB") == 0) ||
1712 (strcmp(ep, "ACCT") == 0))
1713 return (1);
1714 return (0);
1715 }
1716 void
env_opt_end(emptyok)1717 env_opt_end(emptyok)
1718 register int emptyok;
1719 {
1720 register int len;
1721
1722 len = opt_replyp - opt_reply + 2;
1723 if (emptyok || len > OPT_WRAPPER_SIZE) {
1724 *opt_replyp++ = IAC;
1725 *opt_replyp++ = SE;
1726 if (NETROOM() > len) {
1727 ring_supply_data(&netoring, opt_reply, len);
1728 printsub('>', &opt_reply[2], len - 2);
1729 }
1730 else
1731 (void) printf("telnet: not enough room in buffer for "
1732 "environment option end reply\n");
1733 }
1734 if (opt_reply) {
1735 free(opt_reply);
1736 opt_reply = opt_replyp = opt_replyend = NULL;
1737 }
1738 }
1739
1740
1741
1742 int
telrcv()1743 telrcv()
1744 {
1745 register int c;
1746 register int scc;
1747 register unsigned char *sbp;
1748 int count;
1749 int returnValue = 0;
1750 int min_room = 0;
1751
1752 scc = 0;
1753 count = 0;
1754 while (--min_room > 2 || (min_room = TTYROOM()) > 2) {
1755 if (scc == 0) {
1756 if (count) {
1757 ring_consumed(&netiring, count);
1758 returnValue = 1;
1759 count = 0;
1760 }
1761 sbp = netiring.consume;
1762 scc = ring_full_consecutive(&netiring);
1763 if (scc == 0) {
1764 /* No more data coming in */
1765 break;
1766 }
1767 }
1768
1769 c = *sbp++ & 0xff, scc--; count++;
1770
1771 if (decrypt_input)
1772 c = (*decrypt_input)(c);
1773
1774 switch (telrcv_state) {
1775
1776 case TS_CR:
1777 telrcv_state = TS_DATA;
1778 if (c == '\0') {
1779 break; /* Ignore \0 after CR */
1780 } else if ((c == '\n') &&
1781 my_want_state_is_dont(TELOPT_ECHO) && !crmod) {
1782 TTYADD(c);
1783 break;
1784 }
1785 /* FALLTHROUGH */
1786
1787 case TS_DATA:
1788 if (c == IAC) {
1789 telrcv_state = TS_IAC;
1790 break;
1791 }
1792 /*
1793 * The 'crmod' hack (see following) is needed
1794 * since we can't * set CRMOD on output only.
1795 * Machines like MULTICS like to send \r without
1796 * \n; since we must turn off CRMOD to get proper
1797 * input, the mapping is done here (sigh).
1798 */
1799 if ((c == '\r') &&
1800 my_want_state_is_dont(TELOPT_BINARY)) {
1801 if (scc > 0) {
1802 c = *sbp&0xff;
1803
1804 if (decrypt_input)
1805 c = (*decrypt_input)(c);
1806
1807 if (c == 0) {
1808 sbp++, scc--; count++;
1809 /* a "true" CR */
1810 TTYADD('\r');
1811 } else if (my_want_state_is_dont(
1812 TELOPT_ECHO) && (c == '\n')) {
1813 sbp++, scc--; count++;
1814 TTYADD('\n');
1815 } else {
1816
1817 if (decrypt_input)
1818 (*decrypt_input)(-1);
1819
1820 TTYADD('\r');
1821 if (crmod) {
1822 TTYADD('\n');
1823 }
1824 }
1825 } else {
1826 telrcv_state = TS_CR;
1827 TTYADD('\r');
1828 if (crmod) {
1829 TTYADD('\n');
1830 }
1831 }
1832 } else {
1833 TTYADD(c);
1834 }
1835 continue;
1836
1837 case TS_IAC:
1838 process_iac:
1839 switch (c) {
1840
1841 case WILL:
1842 telrcv_state = TS_WILL;
1843 continue;
1844
1845 case WONT:
1846 telrcv_state = TS_WONT;
1847 continue;
1848
1849 case DO:
1850 telrcv_state = TS_DO;
1851 continue;
1852
1853 case DONT:
1854 telrcv_state = TS_DONT;
1855 continue;
1856
1857 case DM:
1858 /*
1859 * We may have missed an urgent notification,
1860 * so make sure we flush whatever is in the
1861 * buffer currently.
1862 */
1863 printoption("RCVD", IAC, DM);
1864 SYNCHing = 1;
1865 if (ttyflush(1) == -2) {
1866 /* This will not return. */
1867 fatal_tty_error("write");
1868 }
1869 SYNCHing = stilloob();
1870 settimer(gotDM);
1871 break;
1872
1873 case SB:
1874 SB_CLEAR();
1875 telrcv_state = TS_SB;
1876 continue;
1877
1878 case IAC:
1879 TTYADD(IAC);
1880 break;
1881
1882 case NOP:
1883 case GA:
1884 default:
1885 printoption("RCVD", IAC, c);
1886 break;
1887 }
1888 telrcv_state = TS_DATA;
1889 continue;
1890
1891 case TS_WILL:
1892 printoption("RCVD", WILL, c);
1893 willoption(c);
1894 telrcv_state = TS_DATA;
1895 continue;
1896
1897 case TS_WONT:
1898 printoption("RCVD", WONT, c);
1899 wontoption(c);
1900 telrcv_state = TS_DATA;
1901 continue;
1902
1903 case TS_DO:
1904 printoption("RCVD", DO, c);
1905 dooption(c);
1906 if (c == TELOPT_NAWS) {
1907 sendnaws();
1908 } else if (c == TELOPT_LFLOW) {
1909 localflow = 1;
1910 setcommandmode();
1911 setconnmode(0);
1912 }
1913 telrcv_state = TS_DATA;
1914 continue;
1915
1916 case TS_DONT:
1917 printoption("RCVD", DONT, c);
1918 dontoption(c);
1919 flushline = 1;
1920 setconnmode(0); /* set new tty mode (maybe) */
1921 telrcv_state = TS_DATA;
1922 continue;
1923
1924 case TS_SB:
1925 if (c == IAC) {
1926 telrcv_state = TS_SE;
1927 } else {
1928 SB_ACCUM(c);
1929 }
1930 continue;
1931
1932 case TS_SE:
1933 if (c != SE) {
1934 if (c != IAC) {
1935 /*
1936 * This is an error. We only expect to get
1937 * "IAC IAC" or "IAC SE". Several things may
1938 * have happend. An IAC was not doubled, the
1939 * IAC SE was left off, or another option got
1940 * inserted into the suboption are all possibilities.
1941 * If we assume that the IAC was not doubled,
1942 * and really the IAC SE was left off, we could
1943 * get into an infinate loop here. So, instead,
1944 * we terminate the suboption, and process the
1945 * partial suboption if we can.
1946 */
1947 SB_ACCUM(IAC);
1948 SB_ACCUM(c);
1949 subpointer -= 2;
1950 SB_TERM();
1951
1952 printoption("In SUBOPTION processing, "
1953 "RCVD", IAC, c);
1954 suboption(); /* handle sub-option */
1955 telrcv_state = TS_IAC;
1956 goto process_iac;
1957 }
1958 SB_ACCUM(c);
1959 telrcv_state = TS_SB;
1960 } else {
1961 SB_ACCUM(IAC);
1962 SB_ACCUM(SE);
1963 subpointer -= 2;
1964 SB_TERM();
1965 suboption(); /* handle sub-option */
1966 telrcv_state = TS_DATA;
1967 }
1968 }
1969 }
1970 if (count)
1971 ring_consumed(&netiring, count);
1972 return (returnValue||count);
1973 }
1974
1975 static int bol = 1, local = 0;
1976
1977 int
rlogin_susp()1978 rlogin_susp()
1979 {
1980 if (local) {
1981 local = 0;
1982 bol = 1;
1983 command(0, "z\n", 2);
1984 return (1);
1985 }
1986 return (0);
1987 }
1988
1989 static int
telsnd()1990 telsnd()
1991 {
1992 int tcc;
1993 int count;
1994 int returnValue = 0;
1995 unsigned char *tbp;
1996
1997 tcc = 0;
1998 count = 0;
1999 while (NETROOM() > 2) {
2000 register int sc;
2001 register int c;
2002
2003 if (tcc == 0) {
2004 if (count) {
2005 ring_consumed(&ttyiring, count);
2006 returnValue = 1;
2007 count = 0;
2008 }
2009 tbp = ttyiring.consume;
2010 tcc = ring_full_consecutive(&ttyiring);
2011 if (tcc == 0) {
2012 break;
2013 }
2014 }
2015 c = *tbp++ & 0xff, sc = strip(c), tcc--; count++;
2016 if (rlogin != _POSIX_VDISABLE) {
2017 if (bol) {
2018 bol = 0;
2019 if (sc == rlogin) {
2020 local = 1;
2021 continue;
2022 }
2023 } else if (local) {
2024 local = 0;
2025 if (sc == '.' || c == termEofChar) {
2026 bol = 1;
2027 command(0, "close\n", 6);
2028 continue;
2029 }
2030 if (sc == termSuspChar) {
2031 bol = 1;
2032 command(0, "z\n", 2);
2033 continue;
2034 }
2035 if (sc == escape) {
2036 command(0, (char *)tbp, tcc);
2037 bol = 1;
2038 count += tcc;
2039 tcc = 0;
2040 flushline = 1;
2041 break;
2042 }
2043 if (sc != rlogin) {
2044 ++tcc;
2045 --tbp;
2046 --count;
2047 c = sc = rlogin;
2048 }
2049 }
2050 if ((sc == '\n') || (sc == '\r'))
2051 bol = 1;
2052 } else if (sc == escape && escape_valid) {
2053 /*
2054 * Double escape is a pass through of a single
2055 * escape character.
2056 */
2057 if (tcc && strip(*tbp) == escape) {
2058 tbp++;
2059 tcc--;
2060 count++;
2061 bol = 0;
2062 } else {
2063 command(0, (char *)tbp, tcc);
2064 bol = 1;
2065 count += tcc;
2066 tcc = 0;
2067 flushline = 1;
2068 break;
2069 }
2070 } else
2071 bol = 0;
2072 #ifdef KLUDGELINEMODE
2073 if (kludgelinemode && (globalmode&MODE_EDIT) && (sc == echoc)) {
2074 if (tcc > 0 && strip(*tbp) == echoc) {
2075 tcc--; tbp++; count++;
2076 } else {
2077 dontlecho = !dontlecho;
2078 settimer(echotoggle);
2079 setconnmode(0);
2080 flushline = 1;
2081 break;
2082 }
2083 }
2084 #endif
2085 if (MODE_LOCAL_CHARS(globalmode)) {
2086 if (TerminalSpecialChars(sc) == 0) {
2087 bol = 1;
2088 break;
2089 }
2090 }
2091 if (my_want_state_is_wont(TELOPT_BINARY)) {
2092 switch (c) {
2093 case '\n':
2094 /*
2095 * If we are in CRMOD mode (\r ==> \n)
2096 * on our local machine, then probably
2097 * a newline (unix) is CRLF (TELNET).
2098 */
2099 if (MODE_LOCAL_CHARS(globalmode)) {
2100 NETADD('\r');
2101 }
2102 NETADD('\n');
2103 bol = flushline = 1;
2104 break;
2105 case '\r':
2106 if (!crlf) {
2107 NET2ADD('\r', '\0');
2108 } else {
2109 NET2ADD('\r', '\n');
2110 }
2111 bol = flushline = 1;
2112 break;
2113 case IAC:
2114 NET2ADD(IAC, IAC);
2115 break;
2116 default:
2117 NETADD(c);
2118 break;
2119 }
2120 } else if (c == IAC) {
2121 NET2ADD(IAC, IAC);
2122 } else {
2123 NETADD(c);
2124 }
2125 }
2126 if (count)
2127 ring_consumed(&ttyiring, count);
2128 return (returnValue||count); /* Non-zero if we did anything */
2129 }
2130
2131 /*
2132 * Scheduler()
2133 *
2134 * Try to do something.
2135 *
2136 * If we do something useful, return 1; else return 0.
2137 *
2138 */
2139
2140
2141 int
Scheduler(block)2142 Scheduler(block)
2143 int block; /* should we block in the select ? */
2144 {
2145 /*
2146 * One wants to be a bit careful about setting returnValue
2147 * to one, since a one implies we did some useful work,
2148 * and therefore probably won't be called to block next
2149 * time (TN3270 mode only).
2150 */
2151 int returnValue;
2152 int netin, netout, netex, ttyin, ttyout;
2153
2154 /* Decide which rings should be processed */
2155
2156 netout = ring_full_count(&netoring) &&
2157 (flushline ||
2158 (my_want_state_is_wont(TELOPT_LINEMODE)
2159 #ifdef KLUDGELINEMODE
2160 /* X */ && (!kludgelinemode || my_want_state_is_do(TELOPT_SGA))
2161 #endif
2162 /* XXX */) ||
2163 my_want_state_is_will(TELOPT_BINARY));
2164 ttyout = ring_full_count(&ttyoring);
2165
2166 ttyin = (ring_empty_count(&ttyiring) && !eof_pending);
2167
2168 netin = !ISend && ring_empty_count(&netiring);
2169
2170 netex = !SYNCHing;
2171
2172 if (scheduler_lockout_tty) {
2173 ttyin = ttyout = 0;
2174 }
2175
2176 /* Call to system code to process rings */
2177
2178 returnValue = process_rings(netin, netout, netex, ttyin, ttyout,
2179 !block);
2180
2181 /* Now, look at the input rings, looking for work to do. */
2182
2183 if (ring_full_count(&ttyiring)) {
2184 returnValue |= telsnd();
2185 } else {
2186 /*
2187 * If ttyiring is empty, check to see if there is a real EOF
2188 * pending. If so, we can maybe do the EOF write now.
2189 */
2190 if (eof_pending) {
2191 eof_pending = 0;
2192 sendeof();
2193 }
2194 }
2195
2196 if (ring_full_count(&netiring)) {
2197 returnValue |= telrcv();
2198 }
2199 return (returnValue);
2200 }
2201
2202 /*
2203 * Select from tty and network...
2204 */
2205 void
telnet(user)2206 telnet(user)
2207 char *user;
2208 {
2209 sys_telnet_init();
2210
2211 {
2212 static char local_host[MAXHOSTNAMELEN] = { 0 };
2213
2214 if (!local_host[0]) {
2215 (void) gethostname(local_host, sizeof (local_host));
2216 local_host[sizeof (local_host)-1] = 0;
2217 }
2218 auth_encrypt_init(local_host, hostname, "TELNET");
2219 auth_encrypt_user(user);
2220 }
2221
2222 if (autologin)
2223 send_will(TELOPT_AUTHENTICATION, 1);
2224
2225 if (telnetport || wantencryption) {
2226 send_do(TELOPT_ENCRYPT, 1);
2227 send_will(TELOPT_ENCRYPT, 1);
2228 }
2229
2230 if (telnetport) {
2231 if (!reqd_linemode)
2232 send_do(TELOPT_SGA, 1);
2233 send_will(TELOPT_TTYPE, 1);
2234 send_will(TELOPT_NAWS, 1);
2235 send_will(TELOPT_TSPEED, 1);
2236 send_will(TELOPT_LFLOW, 1);
2237 if (!reqd_linemode)
2238 send_will(TELOPT_LINEMODE, 1);
2239 send_will(TELOPT_NEW_ENVIRON, 1);
2240 send_do(TELOPT_STATUS, 1);
2241 if (env_getvalue((unsigned char *)"DISPLAY"))
2242 send_will(TELOPT_XDISPLOC, 1);
2243 if (eight)
2244 tel_enter_binary(eight);
2245 }
2246
2247 /*
2248 * Note: we assume a tie to the authentication option here. This
2249 * is necessary so that authentication fails, we don't spin
2250 * forever.
2251 */
2252 if (wantencryption) {
2253 boolean_t printed_encrypt = B_FALSE;
2254 extern boolean_t auth_has_failed;
2255 time_t timeout = time(0) + 60;
2256
2257 send_do(TELOPT_ENCRYPT, 1);
2258 send_will(TELOPT_ENCRYPT, 1);
2259 for (;;) {
2260 if (my_want_state_is_wont(TELOPT_AUTHENTICATION)) {
2261 (void) printf(gettext(
2262 "\nServer refused to negotiate "
2263 "authentication, which is required\n"
2264 "for encryption. Good-bye.\n\r"));
2265 Exit(EXIT_FAILURE);
2266 }
2267 if (auth_has_failed) {
2268 (void) printf(gettext(
2269 "\nAuthentication negotation has failed, "
2270 "which is required for\n"
2271 "encryption. Good-bye.\n\r"));
2272 Exit(EXIT_FAILURE);
2273 }
2274 if (my_want_state_is_dont(TELOPT_ENCRYPT) ||
2275 my_want_state_is_wont(TELOPT_ENCRYPT)) {
2276 (void) printf(gettext(
2277 "\nServer refused to negotiate encryption. "
2278 "Good-bye.\n\r"));
2279 Exit(EXIT_FAILURE);
2280 }
2281 if (encrypt_is_encrypting())
2282 break;
2283
2284 if (time(0) > timeout) {
2285 (void) printf(gettext(
2286 "\nEncryption could not be enabled. "
2287 "Good-bye.\n\r"));
2288 Exit(EXIT_FAILURE);
2289 }
2290 if (printed_encrypt == B_FALSE) {
2291 printed_encrypt = B_TRUE;
2292 (void) printf(gettext(
2293 "Waiting for encryption to be negotiated...\n"));
2294 /*
2295 * Turn on MODE_TRAPSIG and then turn off localchars
2296 * so that ^C will cause telnet to exit.
2297 */
2298 TerminalNewMode(getconnmode()|MODE_TRAPSIG);
2299 intr_waiting = 1;
2300 }
2301 if (intr_happened) {
2302 (void) printf(gettext(
2303 "\nUser requested an interrupt. Good-bye.\n\r"));
2304 Exit(EXIT_FAILURE);
2305 }
2306 telnet_spin();
2307 }
2308 if (printed_encrypt) {
2309 (void) printf(gettext("done.\n"));
2310 intr_waiting = 0;
2311 setconnmode(0);
2312 }
2313 }
2314
2315 for (;;) {
2316 int schedValue;
2317
2318 while ((schedValue = Scheduler(0)) != 0) {
2319 if (schedValue == -1) {
2320 setcommandmode();
2321 return;
2322 }
2323 }
2324
2325 if (Scheduler(1) == -1) {
2326 setcommandmode();
2327 return;
2328 }
2329 }
2330 }
2331
2332 #if 0 /* XXX - this not being in is a bug */
2333 /*
2334 * nextitem()
2335 *
2336 * Return the address of the next "item" in the TELNET data
2337 * stream. This will be the address of the next character if
2338 * the current address is a user data character, or it will
2339 * be the address of the character following the TELNET command
2340 * if the current address is a TELNET IAC ("I Am a Command")
2341 * character.
2342 */
2343
2344 static char *
2345 nextitem(current)
2346 char *current;
2347 {
2348 if ((*current&0xff) != IAC) {
2349 return (current+1);
2350 }
2351 switch (*(current+1)&0xff) {
2352 case DO:
2353 case DONT:
2354 case WILL:
2355 case WONT:
2356 return (current+3);
2357 case SB: /* loop forever looking for the SE */
2358 {
2359 register char *look = current+2;
2360
2361 for (;;) {
2362 if ((*look++&0xff) == IAC) {
2363 if ((*look++&0xff) == SE) {
2364 return (look);
2365 }
2366 }
2367 }
2368 }
2369 default:
2370 return (current+2);
2371 }
2372 }
2373 #endif /* 0 */
2374
2375 /*
2376 * netclear()
2377 *
2378 * We are about to do a TELNET SYNCH operation. Clear
2379 * the path to the network.
2380 *
2381 * Things are a bit tricky since we may have sent the first
2382 * byte or so of a previous TELNET command into the network.
2383 * So, we have to scan the network buffer from the beginning
2384 * until we are up to where we want to be.
2385 *
2386 * A side effect of what we do, just to keep things
2387 * simple, is to clear the urgent data pointer. The principal
2388 * caller should be setting the urgent data pointer AFTER calling
2389 * us in any case.
2390 */
2391
2392 static void
netclear()2393 netclear()
2394 {
2395 #if 0 /* XXX */
2396 register char *thisitem, *next;
2397 char *good;
2398 #define wewant(p) ((nfrontp > p) && ((*p&0xff) == IAC) && \
2399 ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
2400
2401 thisitem = netobuf;
2402
2403 while ((next = nextitem(thisitem)) <= netobuf.send) {
2404 thisitem = next;
2405 }
2406
2407 /* Now, thisitem is first before/at boundary. */
2408
2409 good = netobuf; /* where the good bytes go */
2410
2411 while (netoring.add > thisitem) {
2412 if (wewant(thisitem)) {
2413 int length;
2414
2415 next = thisitem;
2416 do {
2417 next = nextitem(next);
2418 } while (wewant(next) && (nfrontp > next));
2419 length = next-thisitem;
2420 memcpy(good, thisitem, length);
2421 good += length;
2422 thisitem = next;
2423 } else {
2424 thisitem = nextitem(thisitem);
2425 }
2426 }
2427
2428 #endif /* 0 */
2429 }
2430
2431 /*
2432 * These routines add various telnet commands to the data stream.
2433 */
2434
2435 /*
2436 * doflush - Send do timing mark (for network connection flush) & then
2437 * get rid of anything in the output buffer. Return -1 if there was a
2438 * non-EWOULDBLOCK error on the tty flush, and otherwise return 0.
2439 */
2440 static int
doflush()2441 doflush()
2442 {
2443 NET2ADD(IAC, DO);
2444 NETADD(TELOPT_TM);
2445 flushline = 1;
2446 flushout = 1;
2447
2448 /* Drop pending tty output */
2449 if (ttyflush(1) == -2)
2450 return (-1);
2451
2452 /* do printoption AFTER flush, otherwise the output gets tossed... */
2453 printoption("SENT", DO, TELOPT_TM);
2454 return (0);
2455 }
2456
2457 int
xmitAO()2458 xmitAO()
2459 {
2460 NET2ADD(IAC, AO);
2461 printoption("SENT", IAC, AO);
2462 if (autoflush) {
2463 if (doflush() == -1)
2464 return (-1);
2465 }
2466 return (0);
2467 }
2468
2469
2470 void
xmitEL()2471 xmitEL()
2472 {
2473 NET2ADD(IAC, EL);
2474 printoption("SENT", IAC, EL);
2475 }
2476
2477 void
xmitEC()2478 xmitEC()
2479 {
2480 NET2ADD(IAC, EC);
2481 printoption("SENT", IAC, EC);
2482 }
2483
2484
2485 int
dosynch()2486 dosynch()
2487 {
2488 netclear(); /* clear the path to the network */
2489 NETADD(IAC);
2490 setneturg();
2491 NETADD(DM);
2492 printoption("SENT", IAC, DM);
2493 return (1);
2494 }
2495
2496 int want_status_response = 0;
2497
2498 int
get_status()2499 get_status()
2500 {
2501 unsigned char tmp[16];
2502 register unsigned char *cp;
2503
2504 if (my_want_state_is_dont(TELOPT_STATUS)) {
2505 (void) printf("Remote side does not support STATUS option\n");
2506 return (0);
2507 }
2508 cp = tmp;
2509
2510 *cp++ = IAC;
2511 *cp++ = SB;
2512 *cp++ = TELOPT_STATUS;
2513 *cp++ = TELQUAL_SEND;
2514 *cp++ = IAC;
2515 *cp++ = SE;
2516 if (NETROOM() >= cp - tmp) {
2517 ring_supply_data(&netoring, tmp, cp-tmp);
2518 printsub('>', tmp+2, cp - tmp - 2);
2519 }
2520 ++want_status_response;
2521 return (1);
2522 }
2523
2524 void
intp()2525 intp()
2526 {
2527 NET2ADD(IAC, IP);
2528 printoption("SENT", IAC, IP);
2529 flushline = 1;
2530 if (autoflush) {
2531 /* Ignore return as we're ending off anyway. */
2532 (void) doflush();
2533 }
2534 if (autosynch) {
2535 (void) dosynch();
2536 }
2537 }
2538
2539 int
sendbrk()2540 sendbrk()
2541 {
2542 NET2ADD(IAC, BREAK);
2543 printoption("SENT", IAC, BREAK);
2544 flushline = 1;
2545 if (autoflush) {
2546 if (doflush() == -1)
2547 return (-1);
2548 }
2549 if (autosynch) {
2550 (void) dosynch();
2551 }
2552 return (0);
2553 }
2554
2555 void
sendabort()2556 sendabort()
2557 {
2558 NET2ADD(IAC, ABORT);
2559 printoption("SENT", IAC, ABORT);
2560 flushline = 1;
2561 if (autoflush) {
2562 /*
2563 * Since sendabort() gets called while aborting,
2564 * ignore the doflush() return
2565 */
2566 (void) doflush();
2567 }
2568 if (autosynch) {
2569 (void) dosynch();
2570 }
2571 }
2572
2573 void
sendsusp()2574 sendsusp()
2575 {
2576 NET2ADD(IAC, SUSP);
2577 printoption("SENT", IAC, SUSP);
2578 flushline = 1;
2579 if (autoflush) {
2580 if (doflush() == -1) {
2581 /* The following will not return. */
2582 fatal_tty_error("write");
2583 }
2584 }
2585 if (autosynch) {
2586 (void) dosynch();
2587 }
2588 }
2589
2590 static void
sendeof()2591 sendeof()
2592 {
2593 NET2ADD(IAC, xEOF);
2594 printoption("SENT", IAC, xEOF);
2595 }
2596
2597 /*
2598 * Send a window size update to the remote system.
2599 */
2600
2601 void
sendnaws()2602 sendnaws()
2603 {
2604 unsigned short rows, cols;
2605 unsigned char tmp[16];
2606 register unsigned char *cp;
2607
2608 if (my_state_is_wont(TELOPT_NAWS))
2609 return;
2610
2611 #define PUTSHORT(cp, x) { if ((*cp++ = ((x)>>8)&0xff) == IAC) *cp++ = IAC; \
2612 if ((*cp++ = ((x))&0xff) == IAC) *cp++ = IAC; }
2613
2614 if (TerminalWindowSize(&rows, &cols) == 0) { /* Failed */
2615 return;
2616 }
2617
2618 cp = tmp;
2619
2620 *cp++ = IAC;
2621 *cp++ = SB;
2622 *cp++ = TELOPT_NAWS;
2623 PUTSHORT(cp, cols);
2624 PUTSHORT(cp, rows);
2625 *cp++ = IAC;
2626 *cp++ = SE;
2627 if (NETROOM() >= cp - tmp) {
2628 ring_supply_data(&netoring, tmp, cp-tmp);
2629 printsub('>', tmp+2, cp - tmp - 2);
2630 }
2631 }
2632
2633 void
tel_enter_binary(rw)2634 tel_enter_binary(rw)
2635 int rw;
2636 {
2637 if (rw&1)
2638 send_do(TELOPT_BINARY, 1);
2639 if (rw&2)
2640 send_will(TELOPT_BINARY, 1);
2641 }
2642
2643 void
tel_leave_binary(rw)2644 tel_leave_binary(rw)
2645 int rw;
2646 {
2647 if (rw&1)
2648 send_dont(TELOPT_BINARY, 1);
2649 if (rw&2)
2650 send_wont(TELOPT_BINARY, 1);
2651 }
2652