2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
34 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
39 static const char sccsid[] = "@(#)termstat.c 8.2 (Berkeley) 5/30/95";
45 #include <libtelnet/encrypt.h>
51 int def_tspeed = -1, def_rspeed = -1;
53 int def_row = 0, def_col = 0;
56 static int _terminit = 0;
63 * This function handles all management of linemode.
65 * Linemode allows the client to do the local editing of data
66 * and send only complete lines to the server. Linemode state is
67 * based on the state of the pty driver. If the pty is set for
68 * external processing, then we can use linemode. Further, if we
69 * can use real linemode, then we can look at the edit control bits
70 * in the pty to determine what editing the client should do.
72 * Linemode support uses the following state flags to keep track of
73 * current and desired linemode state.
74 * alwayslinemode : true if -l was specified on the telnetd
75 * command line. It means to have linemode on as much as
78 * lmodetype: signifies whether the client can
79 * handle real linemode, or if use of kludgeomatic linemode
80 * is preferred. It will be set to one of the following:
81 * REAL_LINEMODE : use linemode option
82 * NO_KLUDGE : don't initiate kludge linemode.
83 * KLUDGE_LINEMODE : use kludge linemode
84 * NO_LINEMODE : client is ignorant of linemode
86 * linemode, uselinemode : linemode is true if linemode
87 * is currently on, uselinemode is the state that we wish
88 * to be in. If another function wishes to turn linemode
89 * on or off, it sets or clears uselinemode.
91 * editmode, useeditmode : like linemode/uselinemode, but
92 * these contain the edit mode states (edit and trapsig).
94 * The state variables correspond to some of the state information
97 * In real linemode, this corresponds to whether the pty
98 * expects external processing of incoming data.
99 * In kludge linemode, this more closely corresponds to the
100 * whether normal processing is on or not. (ICANON in
101 * system V, or COOKED mode in BSD.)
102 * If the -l option was specified (alwayslinemode), then
103 * an attempt is made to force external processing on at
106 * The following heuristics are applied to determine linemode
107 * handling within the server.
108 * 1) Early on in starting up the server, an attempt is made
109 * to negotiate the linemode option. If this succeeds
110 * then lmodetype is set to REAL_LINEMODE and all linemode
111 * processing occurs in the context of the linemode option.
112 * 2) If the attempt to negotiate the linemode option failed,
113 * and the "-k" (don't initiate kludge linemode) isn't set,
114 * then we try to use kludge linemode. We test for this
115 * capability by sending "do Timing Mark". If a positive
116 * response comes back, then we assume that the client
117 * understands kludge linemode (ech!) and the
118 * lmodetype flag is set to KLUDGE_LINEMODE.
119 * 3) Otherwise, linemode is not supported at all and
120 * lmodetype remains set to NO_LINEMODE (which happens
121 * to be 0 for convenience).
122 * 4) At any time a command arrives that implies a higher
123 * state of linemode support in the client, we move to that
126 * A short explanation of kludge linemode is in order here.
127 * 1) The heuristic to determine support for kludge linemode
128 * is to send a do timing mark. We assume that a client
129 * that supports timing marks also supports kludge linemode.
130 * A risky proposition at best.
131 * 2) Further negotiation of linemode is done by changing the
132 * the server's state regarding SGA. If server will SGA,
133 * then linemode is off, if server won't SGA, then linemode
139 int need_will_echo = 0;
142 * Check for changes to flow control if client supports it.
147 * Check linemode on/off state
149 uselinemode = tty_linemode();
152 * If alwayslinemode is on, and pty is changing to turn it off, then
153 * force linemode back on.
155 if (alwayslinemode && linemode && !uselinemode) {
157 tty_setlinemode(uselinemode);
162 * Check for state of BINARY options.
164 * We only need to do the binary dance if we are actually going
165 * to use linemode. As this confuses some telnet clients
166 * that don't support linemode, and doesn't gain us
167 * anything, we don't do it unless we're doing linemode.
168 * -Crh (henrich@msu.edu)
171 if (tty_isbinaryin()) {
172 if (his_want_state_is_wont(TELOPT_BINARY))
173 send_do(TELOPT_BINARY, 1);
175 if (his_want_state_is_will(TELOPT_BINARY))
176 send_dont(TELOPT_BINARY, 1);
179 if (tty_isbinaryout()) {
180 if (my_want_state_is_wont(TELOPT_BINARY))
181 send_will(TELOPT_BINARY, 1);
183 if (my_want_state_is_will(TELOPT_BINARY))
184 send_wont(TELOPT_BINARY, 1);
190 * If the terminal is not echoing, but editing is enabled,
191 * something like password input is going to happen, so
192 * if we the other side is not currently sending encrypted
193 * data, ask the other side to start encrypting.
195 if (his_state_is_will(TELOPT_ENCRYPT)) {
196 static int enc_passwd = 0;
197 if (uselinemode && !tty_isecho() && tty_isediting()
198 && (enc_passwd == 0) && !decrypt_input) {
199 encrypt_send_request_start();
201 } else if (enc_passwd) {
202 encrypt_send_request_end();
206 #endif /* ENCRYPTION */
209 * Do echo mode handling as soon as we know what the
210 * linemode is going to be.
211 * If the pty has echo turned off, then tell the client that
212 * the server will echo. If echo is on, then the server
213 * will echo if in character mode, but in linemode the
214 * client should do local echoing. The state machine will
215 * not send anything if it is unnecessary, so don't worry
218 * If we need to send the WILL ECHO (because echo is off),
219 * then delay that until after we have changed the MODE.
220 * This way, when the user is turning off both editing
221 * and echo, the client will get editing turned off first.
222 * This keeps the client from going into encryption mode
223 * and then right back out if it is doing auto-encryption
224 * when passwords are being typed.
228 send_wont(TELOPT_ECHO, 1);
231 #ifdef KLUDGELINEMODE
232 if (lmodetype == KLUDGE_OK)
233 lmodetype = KLUDGE_LINEMODE;
238 * If linemode is being turned off, send appropriate
239 * command and then we're all done.
241 if (!uselinemode && linemode) {
242 # ifdef KLUDGELINEMODE
243 if (lmodetype == REAL_LINEMODE) {
244 # endif /* KLUDGELINEMODE */
245 send_dont(TELOPT_LINEMODE, 1);
246 # ifdef KLUDGELINEMODE
247 } else if (lmodetype == KLUDGE_LINEMODE)
248 send_will(TELOPT_SGA, 1);
249 # endif /* KLUDGELINEMODE */
250 send_will(TELOPT_ECHO, 1);
251 linemode = uselinemode;
255 # ifdef KLUDGELINEMODE
257 * If using real linemode check edit modes for possible later use.
258 * If we are in kludge linemode, do the SGA negotiation.
260 if (lmodetype == REAL_LINEMODE) {
261 # endif /* KLUDGELINEMODE */
264 useeditmode |= MODE_EDIT;
266 useeditmode |= MODE_TRAPSIG;
268 useeditmode |= MODE_SOFT_TAB;
270 useeditmode |= MODE_LIT_ECHO;
271 # ifdef KLUDGELINEMODE
272 } else if (lmodetype == KLUDGE_LINEMODE) {
273 if (tty_isediting() && uselinemode)
274 send_wont(TELOPT_SGA, 1);
276 send_will(TELOPT_SGA, 1);
278 # endif /* KLUDGELINEMODE */
281 * Negotiate linemode on if pty state has changed to turn it on.
282 * Send appropriate command and send along edit mode, then all done.
284 if (uselinemode && !linemode) {
285 # ifdef KLUDGELINEMODE
286 if (lmodetype == KLUDGE_LINEMODE) {
287 send_wont(TELOPT_SGA, 1);
288 } else if (lmodetype == REAL_LINEMODE) {
289 # endif /* KLUDGELINEMODE */
290 send_do(TELOPT_LINEMODE, 1);
291 /* send along edit modes */
292 output_data("%c%c%c%c%c%c%c", IAC, SB,
293 TELOPT_LINEMODE, LM_MODE, useeditmode,
295 editmode = useeditmode;
296 # ifdef KLUDGELINEMODE
298 # endif /* KLUDGELINEMODE */
299 linemode = uselinemode;
303 # ifdef KLUDGELINEMODE
305 * None of what follows is of any value if not using
308 if (lmodetype < REAL_LINEMODE)
310 # endif /* KLUDGELINEMODE */
312 if (linemode && his_state_is_will(TELOPT_LINEMODE)) {
314 * If edit mode changed, send edit mode.
316 if (useeditmode != editmode) {
318 * Send along appropriate edit mode mask.
320 output_data("%c%c%c%c%c%c%c", IAC, SB,
321 TELOPT_LINEMODE, LM_MODE, useeditmode,
323 editmode = useeditmode;
328 * Check for changes to special characters in use.
337 send_will(TELOPT_ECHO, 1);
339 * Some things should be deferred until after the pty state has
340 * been set by the local process. Do those things that have been
341 * deferred now. This only happens once.
343 if (_terminit == 0) {
352 } /* end of localstat */
353 #endif /* LINEMODE */
358 * Check for changes to flow control
363 if (his_state_is_will(TELOPT_LFLOW)) {
364 if (tty_flowmode() != flowmode) {
365 flowmode = tty_flowmode();
366 output_data("%c%c%c%c%c%c",
367 IAC, SB, TELOPT_LFLOW,
368 flowmode ? LFLOW_ON : LFLOW_OFF,
371 if (tty_restartany() != restartany) {
372 restartany = tty_restartany();
373 output_data("%c%c%c%c%c%c",
374 IAC, SB, TELOPT_LFLOW,
375 restartany ? LFLOW_RESTART_ANY
385 * Process linemode related requests from the client.
386 * Client can request a change to only one of linemode, editmode or slc's
387 * at a time, and if using kludge linemode, then only linemode may be
391 clientstat(int code, int parm1, int parm2)
395 * Get a copy of terminal characteristics.
400 * Process request from client. code tells what it is.
404 case TELOPT_LINEMODE:
406 * Don't do anything unless client is asking us to change
409 uselinemode = (parm1 == WILL);
410 if (uselinemode != linemode) {
411 # ifdef KLUDGELINEMODE
413 * If using kludge linemode, make sure that
414 * we can do what the client asks.
415 * We can not turn off linemode if alwayslinemode
416 * and the ICANON bit is set.
418 if (lmodetype == KLUDGE_LINEMODE) {
419 if (alwayslinemode && tty_isediting()) {
425 * Quit now if we can't do it.
427 if (uselinemode == linemode)
431 * If using real linemode and linemode is being
432 * turned on, send along the edit mode mask.
434 if (lmodetype == REAL_LINEMODE && uselinemode)
435 # else /* KLUDGELINEMODE */
437 # endif /* KLUDGELINEMODE */
441 useeditmode |= MODE_EDIT;
443 useeditmode |= MODE_TRAPSIG;
445 useeditmode |= MODE_SOFT_TAB;
447 useeditmode |= MODE_LIT_ECHO;
448 output_data("%c%c%c%c%c%c%c", IAC,
449 SB, TELOPT_LINEMODE, LM_MODE,
450 useeditmode, IAC, SE);
451 editmode = useeditmode;
455 tty_setlinemode(uselinemode);
457 linemode = uselinemode;
460 send_will(TELOPT_ECHO, 1);
469 * Client has sent along a mode mask. If it agrees with
470 * what we are currently doing, ignore it; if not, it could
471 * be viewed as a request to change. Note that the server
472 * will change to the modes in an ack if it is different from
473 * what we currently have, but we will not ack the ack.
475 useeditmode &= MODE_MASK;
476 ack = (useeditmode & MODE_ACK);
477 useeditmode &= ~MODE_ACK;
479 if ((changed = (useeditmode ^ editmode))) {
481 * This check is for a timing problem. If the
482 * state of the tty has changed (due to the user
483 * application) we need to process that info
484 * before we write in the state contained in the
485 * ack!!! This gets out the new MODE request,
486 * and when the ack to that command comes back
487 * we'll set it and be in the right mode.
491 if (changed & MODE_EDIT)
492 tty_setedit(useeditmode & MODE_EDIT);
494 if (changed & MODE_TRAPSIG)
495 tty_setsig(useeditmode & MODE_TRAPSIG);
497 if (changed & MODE_SOFT_TAB)
498 tty_setsofttab(useeditmode & MODE_SOFT_TAB);
500 if (changed & MODE_LIT_ECHO)
501 tty_setlitecho(useeditmode & MODE_LIT_ECHO);
506 output_data("%c%c%c%c%c%c%c", IAC,
507 SB, TELOPT_LINEMODE, LM_MODE,
508 useeditmode|MODE_ACK,
512 editmode = useeditmode;
517 } /* end of case LM_MODE */
518 #endif /* LINEMODE */
529 * Defer changing window size until after terminal is
534 #endif /* LINEMODE */
537 * Change window size as requested by client.
542 (void) ioctl(pty, TIOCSWINSZ, (char *)&ws);
544 #endif /* TIOCSWINSZ */
554 * Defer changing the terminal speed.
558 #endif /* LINEMODE */
560 * Change terminal speed as requested by client.
561 * We set the receive speed first, so that if we can't
562 * store separate receive and transmit speeds, the transmit
563 * speed will take precedence.
571 } /* end of case TELOPT_TSPEED */
576 } /* end of switch */
580 } /* end of clientstat */
586 * Some things should not be done until after the login process has started
587 * and all the pty modes are set to what they are supposed to be. This
588 * function is called when the pty state has been processed for the first time.
589 * It calls other functions that do things that were deferred in each module.
596 * local stuff that got deferred.
598 if (def_tspeed != -1) {
599 clientstat(TELOPT_TSPEED, def_tspeed, def_rspeed);
600 def_tspeed = def_rspeed = 0;
604 if (def_col || def_row) {
607 memset((char *)&ws, 0, sizeof(ws));
610 (void) ioctl(pty, TIOCSWINSZ, (char *)&ws);
615 * The only other module that currently defers anything.
619 } /* end of defer_terminit */
624 * Returns true if the pty state has been processed yet.
631 } /* end of terminit */
632 #endif /* LINEMODE */