1 /* $NetBSD: termstat.c,v 1.13 2003/08/07 09:46:52 agc Exp $ */
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 #include <sys/cdefs.h>
35 static char sccsid
[] = "@(#)termstat.c 8.2 (Berkeley) 5/30/95";
37 __RCSID("$NetBSD: termstat.c,v 1.13 2003/08/07 09:46:52 agc Exp $");
44 #include <libtelnet/encrypt.h>
50 int def_tspeed
= -1, def_rspeed
= -1;
51 int def_row
= 0, def_col
= 0;
53 static int _terminit
= 0;
61 * This function handles all management of linemode.
63 * Linemode allows the client to do the local editing of data
64 * and send only complete lines to the server. Linemode state is
65 * based on the state of the pty driver. If the pty is set for
66 * external processing, then we can use linemode. Further, if we
67 * can use real linemode, then we can look at the edit control bits
68 * in the pty to determine what editing the client should do.
70 * Linemode support uses the following state flags to keep track of
71 * current and desired linemode state.
72 * alwayslinemode : true if -l was specified on the telnetd
73 * command line. It means to have linemode on as much as
76 * lmodetype: signifies whether the client can
77 * handle real linemode, or if use of kludgeomatic linemode
78 * is preferred. It will be set to one of the following:
79 * REAL_LINEMODE : use linemode option
80 * NO_KLUDGE : don't initiate kludge linemode.
81 * KLUDGE_LINEMODE : use kludge linemode
82 * NO_LINEMODE : client is ignorant of linemode
84 * linemode, uselinemode : linemode is true if linemode
85 * is currently on, uselinemode is the state that we wish
86 * to be in. If another function wishes to turn linemode
87 * on or off, it sets or clears uselinemode.
89 * editmode, useeditmode : like linemode/uselinemode, but
90 * these contain the edit mode states (edit and trapsig).
92 * The state variables correspond to some of the state information
95 * In real linemode, this corresponds to whether the pty
96 * expects external processing of incoming data.
97 * In kludge linemode, this more closely corresponds to the
98 * whether normal processing is on or not. (ICANON in
99 * system V, or COOKED mode in BSD.)
100 * If the -l option was specified (alwayslinemode), then
101 * an attempt is made to force external processing on at
104 * The following heuristics are applied to determine linemode
105 * handling within the server.
106 * 1) Early on in starting up the server, an attempt is made
107 * to negotiate the linemode option. If this succeeds
108 * then lmodetype is set to REAL_LINEMODE and all linemode
109 * processing occurs in the context of the linemode option.
110 * 2) If the attempt to negotiate the linemode option failed,
111 * and the "-k" (don't initiate kludge linemode) isn't set,
112 * then we try to use kludge linemode. We test for this
113 * capability by sending "do Timing Mark". If a positive
114 * response comes back, then we assume that the client
115 * understands kludge linemode (ech!) and the
116 * lmodetype flag is set to KLUDGE_LINEMODE.
117 * 3) Otherwise, linemode is not supported at all and
118 * lmodetype remains set to NO_LINEMODE (which happens
119 * to be 0 for convenience).
120 * 4) At any time a command arrives that implies a higher
121 * state of linemode support in the client, we move to that
124 * A short explanation of kludge linemode is in order here.
125 * 1) The heuristic to determine support for kludge linemode
126 * is to send a do timing mark. We assume that a client
127 * that supports timing marks also supports kludge linemode.
128 * A risky proposition at best.
129 * 2) Further negotiation of linemode is done by changing the
130 * the server's state regarding SGA. If server will SGA,
131 * then linemode is off, if server won't SGA, then linemode
137 int need_will_echo
= 0;
141 * Check for state of BINARY options.
143 if (tty_isbinaryin()) {
144 if (his_want_state_is_wont(TELOPT_BINARY
))
145 send_do(TELOPT_BINARY
, 1);
147 if (his_want_state_is_will(TELOPT_BINARY
))
148 send_dont(TELOPT_BINARY
, 1);
151 if (tty_isbinaryout()) {
152 if (my_want_state_is_wont(TELOPT_BINARY
))
153 send_will(TELOPT_BINARY
, 1);
155 if (my_want_state_is_will(TELOPT_BINARY
))
156 send_wont(TELOPT_BINARY
, 1);
160 * Check for changes to flow control if client supports it.
165 * Check linemode on/off state
167 uselinemode
= tty_linemode();
170 * If alwayslinemode is on, and pty is changing to turn it off, then
171 * force linemode back on.
173 if (alwayslinemode
&& linemode
&& !uselinemode
) {
175 tty_setlinemode(uselinemode
);
180 * If the terminal is not echoing, but editing is enabled,
181 * something like password input is going to happen, so
182 * if we the other side is not currently sending encrypted
183 * data, ask the other side to start encrypting.
185 if (his_state_is_will(TELOPT_ENCRYPT
)) {
186 static int enc_passwd
= 0;
187 if (uselinemode
&& !tty_isecho() && tty_isediting()
188 && (enc_passwd
== 0) && !decrypt_input
) {
189 encrypt_send_request_start();
191 } else if (enc_passwd
) {
192 encrypt_send_request_end();
196 #endif /* ENCRYPTION */
199 * Do echo mode handling as soon as we know what the
200 * linemode is going to be.
201 * If the pty has echo turned off, then tell the client that
202 * the server will echo. If echo is on, then the server
203 * will echo if in character mode, but in linemode the
204 * client should do local echoing. The state machine will
205 * not send anything if it is unnecessary, so don't worry
208 * If we need to send the WILL ECHO (because echo is off),
209 * then delay that until after we have changed the MODE.
210 * This way, when the user is turning off both editing
211 * and echo, the client will get editing turned off first.
212 * This keeps the client from going into encryption mode
213 * and then right back out if it is doing auto-encryption
214 * when passwords are being typed.
218 send_wont(TELOPT_ECHO
, 1);
221 #ifdef KLUDGELINEMODE
222 if (lmodetype
== KLUDGE_OK
)
223 lmodetype
= KLUDGE_LINEMODE
;
228 * If linemode is being turned off, send appropriate
229 * command and then we're all done.
231 if (!uselinemode
&& linemode
) {
232 # ifdef KLUDGELINEMODE
233 if (lmodetype
== REAL_LINEMODE
) {
234 # endif /* KLUDGELINEMODE */
235 send_dont(TELOPT_LINEMODE
, 1);
236 # ifdef KLUDGELINEMODE
237 } else if (lmodetype
== KLUDGE_LINEMODE
)
238 send_will(TELOPT_SGA
, 1);
239 # endif /* KLUDGELINEMODE */
240 send_will(TELOPT_ECHO
, 1);
241 linemode
= uselinemode
;
245 # ifdef KLUDGELINEMODE
247 * If using real linemode check edit modes for possible later use.
248 * If we are in kludge linemode, do the SGA negotiation.
250 if (lmodetype
== REAL_LINEMODE
) {
251 # endif /* KLUDGELINEMODE */
254 useeditmode
|= MODE_EDIT
;
256 useeditmode
|= MODE_TRAPSIG
;
258 useeditmode
|= MODE_SOFT_TAB
;
260 useeditmode
|= MODE_LIT_ECHO
;
261 # ifdef KLUDGELINEMODE
262 } else if (lmodetype
== KLUDGE_LINEMODE
) {
263 if (tty_isediting() && uselinemode
)
264 send_wont(TELOPT_SGA
, 1);
266 send_will(TELOPT_SGA
, 1);
268 # endif /* KLUDGELINEMODE */
271 * Negotiate linemode on if pty state has changed to turn it on.
272 * Send appropriate command and send along edit mode, then all done.
274 if (uselinemode
&& !linemode
) {
275 # ifdef KLUDGELINEMODE
276 if (lmodetype
== KLUDGE_LINEMODE
) {
277 send_wont(TELOPT_SGA
, 1);
278 } else if (lmodetype
== REAL_LINEMODE
) {
279 # endif /* KLUDGELINEMODE */
280 send_do(TELOPT_LINEMODE
, 1);
281 /* send along edit modes */
282 (void) output_data("%c%c%c%c%c%c%c", IAC
, SB
,
283 TELOPT_LINEMODE
, LM_MODE
, useeditmode
,
285 editmode
= useeditmode
;
286 # ifdef KLUDGELINEMODE
288 # endif /* KLUDGELINEMODE */
289 linemode
= uselinemode
;
293 # ifdef KLUDGELINEMODE
295 * None of what follows is of any value if not using
298 if (lmodetype
< REAL_LINEMODE
)
300 # endif /* KLUDGELINEMODE */
302 if (linemode
&& his_state_is_will(TELOPT_LINEMODE
)) {
304 * If edit mode changed, send edit mode.
306 if (useeditmode
!= editmode
) {
308 * Send along appropriate edit mode mask.
310 (void) output_data("%c%c%c%c%c%c%c", IAC
, SB
,
311 TELOPT_LINEMODE
, LM_MODE
, useeditmode
,
313 editmode
= useeditmode
;
318 * Check for changes to special characters in use.
327 send_will(TELOPT_ECHO
, 1);
329 * Some things should be deferred until after the pty state has
330 * been set by the local process. Do those things that have been
331 * deferred now. This only happens once.
333 if (_terminit
== 0) {
342 } /* end of localstat */
343 #endif /* LINEMODE */
348 * Check for changes to flow control
353 if (his_state_is_will(TELOPT_LFLOW
)) {
354 if (tty_flowmode() != flowmode
) {
355 flowmode
= tty_flowmode();
356 (void) output_data("%c%c%c%c%c%c",
357 IAC
, SB
, TELOPT_LFLOW
,
358 flowmode
? LFLOW_ON
: LFLOW_OFF
,
361 if (tty_restartany() != restartany
) {
362 restartany
= tty_restartany();
363 (void) output_data("%c%c%c%c%c%c",
364 IAC
, SB
, TELOPT_LFLOW
,
365 restartany
? LFLOW_RESTART_ANY
375 * Process linemode related requests from the client.
376 * Client can request a change to only one of linemode, editmode or slc's
377 * at a time, and if using kludge linemode, then only linemode may be
381 clientstat(int code
, int parm1
, int parm2
)
385 * Get a copy of terminal characteristics.
390 * Process request from client. code tells what it is.
394 case TELOPT_LINEMODE
:
396 * Don't do anything unless client is asking us to change
399 uselinemode
= (parm1
== WILL
);
400 if (uselinemode
!= linemode
) {
401 # ifdef KLUDGELINEMODE
403 * If using kludge linemode, make sure that
404 * we can do what the client asks.
405 * We can not turn off linemode if alwayslinemode
406 * and the ICANON bit is set.
408 if (lmodetype
== KLUDGE_LINEMODE
) {
409 if (alwayslinemode
&& tty_isediting()) {
415 * Quit now if we can't do it.
417 if (uselinemode
== linemode
)
421 * If using real linemode and linemode is being
422 * turned on, send along the edit mode mask.
424 if (lmodetype
== REAL_LINEMODE
&& uselinemode
)
425 # else /* KLUDGELINEMODE */
427 # endif /* KLUDGELINEMODE */
431 useeditmode
|= MODE_EDIT
;
433 useeditmode
|= MODE_TRAPSIG
;
435 useeditmode
|= MODE_SOFT_TAB
;
437 useeditmode
|= MODE_LIT_ECHO
;
438 (void) output_data("%c%c%c%c%c%c%c", IAC
,
439 SB
, TELOPT_LINEMODE
, LM_MODE
,
440 useeditmode
, IAC
, SE
);
441 editmode
= useeditmode
;
445 tty_setlinemode(uselinemode
);
447 linemode
= uselinemode
;
450 send_will(TELOPT_ECHO
, 1);
459 * Client has sent along a mode mask. If it agrees with
460 * what we are currently doing, ignore it; if not, it could
461 * be viewed as a request to change. Note that the server
462 * will change to the modes in an ack if it is different from
463 * what we currently have, but we will not ack the ack.
465 useeditmode
&= MODE_MASK
;
466 ack
= (useeditmode
& MODE_ACK
);
467 useeditmode
&= ~MODE_ACK
;
469 if ((changed
= (useeditmode
^ editmode
))) {
471 * This check is for a timing problem. If the
472 * state of the tty has changed (due to the user
473 * application) we need to process that info
474 * before we write in the state contained in the
475 * ack!!! This gets out the new MODE request,
476 * and when the ack to that command comes back
477 * we'll set it and be in the right mode.
481 if (changed
& MODE_EDIT
)
482 tty_setedit(useeditmode
& MODE_EDIT
);
484 if (changed
& MODE_TRAPSIG
)
485 tty_setsig(useeditmode
& MODE_TRAPSIG
);
487 if (changed
& MODE_SOFT_TAB
)
488 tty_setsofttab(useeditmode
& MODE_SOFT_TAB
);
490 if (changed
& MODE_LIT_ECHO
)
491 tty_setlitecho(useeditmode
& MODE_LIT_ECHO
);
496 (void) output_data("%c%c%c%c%c%c%c", IAC
,
497 SB
, TELOPT_LINEMODE
, LM_MODE
,
498 useeditmode
|MODE_ACK
,
502 editmode
= useeditmode
;
507 } /* end of case LM_MODE */
508 #endif /* LINEMODE */
518 * Defer changing window size until after terminal is
523 #endif /* LINEMODE */
526 * Change window size as requested by client.
531 (void) ioctl(pty
, TIOCSWINSZ
, (char *)&ws
);
542 * Defer changing the terminal speed.
546 #endif /* LINEMODE */
548 * Change terminal speed as requested by client.
549 * We set the receive speed first, so that if we can't
550 * store separate receive and transmit speeds, the transmit
551 * speed will take precedence.
559 } /* end of case TELOPT_TSPEED */
564 } /* end of switch */
569 } /* end of clientstat */
576 * Some things should not be done until after the login process has started
577 * and all the pty modes are set to what they are supposed to be. This
578 * function is called when the pty state has been processed for the first time.
579 * It calls other functions that do things that were deferred in each module.
586 * local stuff that got deferred.
588 if (def_tspeed
!= -1) {
589 clientstat(TELOPT_TSPEED
, def_tspeed
, def_rspeed
);
590 def_tspeed
= def_rspeed
= 0;
593 if (def_col
|| def_row
) {
596 memset((char *)&ws
, 0, sizeof(ws
));
599 (void) ioctl(pty
, TIOCSWINSZ
, (char *)&ws
);
603 * The only other module that currently defers anything.
607 } /* end of defer_terminit */
612 * Returns true if the pty state has been processed yet.
619 } /* end of terminit */
620 #endif /* LINEMODE */