1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2008 Ed Schouten <[email protected]>
5 * All rights reserved.
6 *
7 * Portions of this software were developed under sponsorship from Snow
8 * B.V., the Netherlands.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34
35 #include "opt_capsicum.h"
36
37 #include <sys/param.h>
38 #include <sys/capsicum.h>
39 #include <sys/conf.h>
40 #include <sys/cons.h>
41 #include <sys/fcntl.h>
42 #include <sys/file.h>
43 #include <sys/filedesc.h>
44 #include <sys/filio.h>
45 #ifdef COMPAT_43TTY
46 #include <sys/ioctl_compat.h>
47 #endif /* COMPAT_43TTY */
48 #include <sys/kernel.h>
49 #include <sys/limits.h>
50 #include <sys/malloc.h>
51 #include <sys/mount.h>
52 #include <sys/poll.h>
53 #include <sys/priv.h>
54 #include <sys/proc.h>
55 #include <sys/serial.h>
56 #include <sys/signal.h>
57 #include <sys/stat.h>
58 #include <sys/sx.h>
59 #include <sys/sysctl.h>
60 #include <sys/systm.h>
61 #include <sys/tty.h>
62 #include <sys/ttycom.h>
63 #define TTYDEFCHARS
64 #include <sys/ttydefaults.h>
65 #undef TTYDEFCHARS
66 #include <sys/ucred.h>
67 #include <sys/vnode.h>
68
69 #include <machine/stdarg.h>
70
71 static MALLOC_DEFINE(M_TTY, "tty", "tty device");
72
73 static void tty_rel_free(struct tty *tp);
74
75 static TAILQ_HEAD(, tty) tty_list = TAILQ_HEAD_INITIALIZER(tty_list);
76 static struct sx tty_list_sx;
77 SX_SYSINIT(tty_list, &tty_list_sx, "tty list");
78 static unsigned int tty_list_count = 0;
79
80 /* Character device of /dev/console. */
81 static struct cdev *dev_console;
82 static const char *dev_console_filename;
83
84 /*
85 * Flags that are supported and stored by this implementation.
86 */
87 #define TTYSUP_IFLAG (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK|ISTRIP|\
88 INLCR|IGNCR|ICRNL|IXON|IXOFF|IXANY|IMAXBEL)
89 #define TTYSUP_OFLAG (OPOST|ONLCR|TAB3|ONOEOT|OCRNL|ONOCR|ONLRET)
90 #define TTYSUP_LFLAG (ECHOKE|ECHOE|ECHOK|ECHO|ECHONL|ECHOPRT|\
91 ECHOCTL|ISIG|ICANON|ALTWERASE|IEXTEN|TOSTOP|\
92 FLUSHO|NOKERNINFO|NOFLSH)
93 #define TTYSUP_CFLAG (CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\
94 HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\
95 CDSR_OFLOW|CCAR_OFLOW)
96
97 #define TTY_CALLOUT(tp,d) (dev2unit(d) & TTYUNIT_CALLOUT)
98
99 static int tty_drainwait = 5 * 60;
100 SYSCTL_INT(_kern, OID_AUTO, tty_drainwait, CTLFLAG_RWTUN,
101 &tty_drainwait, 0, "Default output drain timeout in seconds");
102
103 /*
104 * Set TTY buffer sizes.
105 */
106
107 #define TTYBUF_MAX 65536
108
109 /*
110 * Allocate buffer space if necessary, and set low watermarks, based on speed.
111 * Note that the ttyxxxq_setsize() functions may drop and then reacquire the tty
112 * lock during memory allocation. They will return ENXIO if the tty disappears
113 * while unlocked.
114 */
115 static int
tty_watermarks(struct tty * tp)116 tty_watermarks(struct tty *tp)
117 {
118 size_t bs = 0;
119 int error;
120
121 /* Provide an input buffer for 2 seconds of data. */
122 if (tp->t_termios.c_cflag & CREAD)
123 bs = MIN(tp->t_termios.c_ispeed / 5, TTYBUF_MAX);
124 error = ttyinq_setsize(&tp->t_inq, tp, bs);
125 if (error != 0)
126 return (error);
127
128 /* Set low watermark at 10% (when 90% is available). */
129 tp->t_inlow = (ttyinq_getallocatedsize(&tp->t_inq) * 9) / 10;
130
131 /* Provide an output buffer for 2 seconds of data. */
132 bs = MIN(tp->t_termios.c_ospeed / 5, TTYBUF_MAX);
133 error = ttyoutq_setsize(&tp->t_outq, tp, bs);
134 if (error != 0)
135 return (error);
136
137 /* Set low watermark at 10% (when 90% is available). */
138 tp->t_outlow = (ttyoutq_getallocatedsize(&tp->t_outq) * 9) / 10;
139
140 return (0);
141 }
142
143 static int
tty_drain(struct tty * tp,int leaving)144 tty_drain(struct tty *tp, int leaving)
145 {
146 sbintime_t timeout_at;
147 size_t bytes;
148 int error;
149
150 if (ttyhook_hashook(tp, getc_inject))
151 /* buffer is inaccessible */
152 return (0);
153
154 /*
155 * For close(), use the recent historic timeout of "1 second without
156 * making progress". For tcdrain(), use t_drainwait as the timeout,
157 * with zero meaning "no timeout" which gives POSIX behavior.
158 */
159 if (leaving)
160 timeout_at = getsbinuptime() + SBT_1S;
161 else if (tp->t_drainwait != 0)
162 timeout_at = getsbinuptime() + SBT_1S * tp->t_drainwait;
163 else
164 timeout_at = 0;
165
166 /*
167 * Poll the output buffer and the hardware for completion, at 10 Hz.
168 * Polling is required for devices which are not able to signal an
169 * interrupt when the transmitter becomes idle (most USB serial devs).
170 * The unusual structure of this loop ensures we check for busy one more
171 * time after tty_timedwait() returns EWOULDBLOCK, so that success has
172 * higher priority than timeout if the IO completed in the last 100mS.
173 */
174 error = 0;
175 bytes = ttyoutq_bytesused(&tp->t_outq);
176 for (;;) {
177 if (ttyoutq_bytesused(&tp->t_outq) == 0 && !ttydevsw_busy(tp))
178 return (0);
179 if (error != 0)
180 return (error);
181 ttydevsw_outwakeup(tp);
182 error = tty_timedwait(tp, &tp->t_outwait, hz / 10);
183 if (error != 0 && error != EWOULDBLOCK)
184 return (error);
185 else if (timeout_at == 0 || getsbinuptime() < timeout_at)
186 error = 0;
187 else if (leaving && ttyoutq_bytesused(&tp->t_outq) < bytes) {
188 /* In close, making progress, grant an extra second. */
189 error = 0;
190 timeout_at += SBT_1S;
191 bytes = ttyoutq_bytesused(&tp->t_outq);
192 }
193 }
194 }
195
196 /*
197 * Though ttydev_enter() and ttydev_leave() seem to be related, they
198 * don't have to be used together. ttydev_enter() is used by the cdev
199 * operations to prevent an actual operation from being processed when
200 * the TTY has been abandoned. ttydev_leave() is used by ttydev_open()
201 * and ttydev_close() to determine whether per-TTY data should be
202 * deallocated.
203 */
204
205 static __inline int
ttydev_enter(struct tty * tp)206 ttydev_enter(struct tty *tp)
207 {
208
209 tty_lock(tp);
210
211 if (tty_gone(tp) || !tty_opened(tp)) {
212 /* Device is already gone. */
213 tty_unlock(tp);
214 return (ENXIO);
215 }
216
217 return (0);
218 }
219
220 static void
ttydev_leave(struct tty * tp)221 ttydev_leave(struct tty *tp)
222 {
223
224 tty_lock_assert(tp, MA_OWNED);
225
226 if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
227 /* Device is still opened somewhere. */
228 tty_unlock(tp);
229 return;
230 }
231
232 tp->t_flags |= TF_OPENCLOSE;
233
234 /* Remove console TTY. */
235 if (constty == tp)
236 constty_clear();
237
238 /* Drain any output. */
239 if (!tty_gone(tp))
240 tty_drain(tp, 1);
241
242 ttydisc_close(tp);
243
244 /* Free i/o queues now since they might be large. */
245 ttyinq_free(&tp->t_inq);
246 tp->t_inlow = 0;
247 ttyoutq_free(&tp->t_outq);
248 tp->t_outlow = 0;
249
250 knlist_clear(&tp->t_inpoll.si_note, 1);
251 knlist_clear(&tp->t_outpoll.si_note, 1);
252
253 if (!tty_gone(tp))
254 ttydevsw_close(tp);
255
256 tp->t_flags &= ~TF_OPENCLOSE;
257 cv_broadcast(&tp->t_dcdwait);
258 tty_rel_free(tp);
259 }
260
261 /*
262 * Operations that are exposed through the character device in /dev.
263 */
264 static int
ttydev_open(struct cdev * dev,int oflags,int devtype __unused,struct thread * td)265 ttydev_open(struct cdev *dev, int oflags, int devtype __unused,
266 struct thread *td)
267 {
268 struct tty *tp;
269 int error;
270
271 tp = dev->si_drv1;
272 error = 0;
273 tty_lock(tp);
274 if (tty_gone(tp)) {
275 /* Device is already gone. */
276 tty_unlock(tp);
277 return (ENXIO);
278 }
279
280 /*
281 * Block when other processes are currently opening or closing
282 * the TTY.
283 */
284 while (tp->t_flags & TF_OPENCLOSE) {
285 error = tty_wait(tp, &tp->t_dcdwait);
286 if (error != 0) {
287 tty_unlock(tp);
288 return (error);
289 }
290 }
291 tp->t_flags |= TF_OPENCLOSE;
292
293 /*
294 * Make sure the "tty" and "cua" device cannot be opened at the
295 * same time. The console is a "tty" device.
296 */
297 if (TTY_CALLOUT(tp, dev)) {
298 if (tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) {
299 error = EBUSY;
300 goto done;
301 }
302 } else {
303 if (tp->t_flags & TF_OPENED_OUT) {
304 error = EBUSY;
305 goto done;
306 }
307 }
308
309 if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
310 error = EBUSY;
311 goto done;
312 }
313
314 if (!tty_opened(tp)) {
315 /* Set proper termios flags. */
316 if (TTY_CALLOUT(tp, dev))
317 tp->t_termios = tp->t_termios_init_out;
318 else
319 tp->t_termios = tp->t_termios_init_in;
320 ttydevsw_param(tp, &tp->t_termios);
321 /* Prevent modem control on callout devices and /dev/console. */
322 if (TTY_CALLOUT(tp, dev) || dev == dev_console)
323 tp->t_termios.c_cflag |= CLOCAL;
324
325 ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
326
327 error = ttydevsw_open(tp);
328 if (error != 0)
329 goto done;
330
331 ttydisc_open(tp);
332 error = tty_watermarks(tp);
333 if (error != 0)
334 goto done;
335 }
336
337 /* Wait for Carrier Detect. */
338 if ((oflags & O_NONBLOCK) == 0 &&
339 (tp->t_termios.c_cflag & CLOCAL) == 0) {
340 while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
341 error = tty_wait(tp, &tp->t_dcdwait);
342 if (error != 0)
343 goto done;
344 }
345 }
346
347 if (dev == dev_console)
348 tp->t_flags |= TF_OPENED_CONS;
349 else if (TTY_CALLOUT(tp, dev))
350 tp->t_flags |= TF_OPENED_OUT;
351 else
352 tp->t_flags |= TF_OPENED_IN;
353 MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
354 (tp->t_flags & TF_OPENED_OUT) == 0);
355
356 done: tp->t_flags &= ~TF_OPENCLOSE;
357 cv_broadcast(&tp->t_dcdwait);
358 ttydev_leave(tp);
359
360 return (error);
361 }
362
363 static int
ttydev_close(struct cdev * dev,int fflag,int devtype __unused,struct thread * td __unused)364 ttydev_close(struct cdev *dev, int fflag, int devtype __unused,
365 struct thread *td __unused)
366 {
367 struct tty *tp = dev->si_drv1;
368
369 tty_lock(tp);
370
371 /*
372 * Don't actually close the device if it is being used as the
373 * console.
374 */
375 MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
376 (tp->t_flags & TF_OPENED_OUT) == 0);
377 if (dev == dev_console)
378 tp->t_flags &= ~TF_OPENED_CONS;
379 else
380 tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
381
382 if (tp->t_flags & TF_OPENED) {
383 tty_unlock(tp);
384 return (0);
385 }
386
387 /* If revoking, flush output now to avoid draining it later. */
388 if (fflag & FREVOKE)
389 tty_flush(tp, FWRITE);
390
391 tp->t_flags &= ~TF_EXCLUDE;
392
393 /* Properly wake up threads that are stuck - revoke(). */
394 tp->t_revokecnt++;
395 tty_wakeup(tp, FREAD|FWRITE);
396 cv_broadcast(&tp->t_bgwait);
397 cv_broadcast(&tp->t_dcdwait);
398
399 ttydev_leave(tp);
400
401 return (0);
402 }
403
404 static __inline int
tty_is_ctty(struct tty * tp,struct proc * p)405 tty_is_ctty(struct tty *tp, struct proc *p)
406 {
407
408 tty_lock_assert(tp, MA_OWNED);
409
410 return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
411 }
412
413 int
tty_wait_background(struct tty * tp,struct thread * td,int sig)414 tty_wait_background(struct tty *tp, struct thread *td, int sig)
415 {
416 struct proc *p = td->td_proc;
417 struct pgrp *pg;
418 ksiginfo_t ksi;
419 int error;
420
421 MPASS(sig == SIGTTIN || sig == SIGTTOU);
422 tty_lock_assert(tp, MA_OWNED);
423
424 for (;;) {
425 PROC_LOCK(p);
426 /*
427 * The process should only sleep, when:
428 * - This terminal is the controlling terminal
429 * - Its process group is not the foreground process
430 * group
431 * - The parent process isn't waiting for the child to
432 * exit
433 * - the signal to send to the process isn't masked
434 */
435 if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
436 /* Allow the action to happen. */
437 PROC_UNLOCK(p);
438 return (0);
439 }
440
441 if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
442 SIGISMEMBER(td->td_sigmask, sig)) {
443 /* Only allow them in write()/ioctl(). */
444 PROC_UNLOCK(p);
445 return (sig == SIGTTOU ? 0 : EIO);
446 }
447
448 pg = p->p_pgrp;
449 if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
450 /* Don't allow the action to happen. */
451 PROC_UNLOCK(p);
452 return (EIO);
453 }
454 PROC_UNLOCK(p);
455
456 /*
457 * Send the signal and sleep until we're the new
458 * foreground process group.
459 */
460 if (sig != 0) {
461 ksiginfo_init(&ksi);
462 ksi.ksi_code = SI_KERNEL;
463 ksi.ksi_signo = sig;
464 sig = 0;
465 }
466 PGRP_LOCK(pg);
467 pgsignal(pg, ksi.ksi_signo, 1, &ksi);
468 PGRP_UNLOCK(pg);
469
470 error = tty_wait(tp, &tp->t_bgwait);
471 if (error)
472 return (error);
473 }
474 }
475
476 static int
ttydev_read(struct cdev * dev,struct uio * uio,int ioflag)477 ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
478 {
479 struct tty *tp = dev->si_drv1;
480 int error;
481
482 error = ttydev_enter(tp);
483 if (error)
484 goto done;
485 error = ttydisc_read(tp, uio, ioflag);
486 tty_unlock(tp);
487
488 /*
489 * The read() call should not throw an error when the device is
490 * being destroyed. Silently convert it to an EOF.
491 */
492 done: if (error == ENXIO)
493 error = 0;
494 return (error);
495 }
496
497 static int
ttydev_write(struct cdev * dev,struct uio * uio,int ioflag)498 ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
499 {
500 struct tty *tp = dev->si_drv1;
501 int error;
502
503 error = ttydev_enter(tp);
504 if (error)
505 return (error);
506
507 if (tp->t_termios.c_lflag & TOSTOP) {
508 error = tty_wait_background(tp, curthread, SIGTTOU);
509 if (error)
510 goto done;
511 }
512
513 if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
514 /* Allow non-blocking writes to bypass serialization. */
515 error = ttydisc_write(tp, uio, ioflag);
516 } else {
517 /* Serialize write() calls. */
518 while (tp->t_flags & TF_BUSY_OUT) {
519 error = tty_wait(tp, &tp->t_outserwait);
520 if (error)
521 goto done;
522 }
523
524 tp->t_flags |= TF_BUSY_OUT;
525 error = ttydisc_write(tp, uio, ioflag);
526 tp->t_flags &= ~TF_BUSY_OUT;
527 cv_signal(&tp->t_outserwait);
528 }
529
530 done: tty_unlock(tp);
531 return (error);
532 }
533
534 static int
ttydev_ioctl(struct cdev * dev,u_long cmd,caddr_t data,int fflag,struct thread * td)535 ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
536 struct thread *td)
537 {
538 struct tty *tp = dev->si_drv1;
539 int error;
540
541 error = ttydev_enter(tp);
542 if (error)
543 return (error);
544
545 switch (cmd) {
546 case TIOCCBRK:
547 case TIOCCONS:
548 case TIOCDRAIN:
549 case TIOCEXCL:
550 case TIOCFLUSH:
551 case TIOCNXCL:
552 case TIOCSBRK:
553 case TIOCSCTTY:
554 case TIOCSETA:
555 case TIOCSETAF:
556 case TIOCSETAW:
557 case TIOCSPGRP:
558 case TIOCSTART:
559 case TIOCSTAT:
560 case TIOCSTI:
561 case TIOCSTOP:
562 case TIOCSWINSZ:
563 #if 0
564 case TIOCSDRAINWAIT:
565 case TIOCSETD:
566 #endif
567 #ifdef COMPAT_43TTY
568 case TIOCLBIC:
569 case TIOCLBIS:
570 case TIOCLSET:
571 case TIOCSETC:
572 case OTIOCSETD:
573 case TIOCSETN:
574 case TIOCSETP:
575 case TIOCSLTC:
576 #endif /* COMPAT_43TTY */
577 /*
578 * If the ioctl() causes the TTY to be modified, let it
579 * wait in the background.
580 */
581 error = tty_wait_background(tp, curthread, SIGTTOU);
582 if (error)
583 goto done;
584 }
585
586 if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
587 struct termios *old = &tp->t_termios;
588 struct termios *new = (struct termios *)data;
589 struct termios *lock = TTY_CALLOUT(tp, dev) ?
590 &tp->t_termios_lock_out : &tp->t_termios_lock_in;
591 int cc;
592
593 /*
594 * Lock state devices. Just overwrite the values of the
595 * commands that are currently in use.
596 */
597 new->c_iflag = (old->c_iflag & lock->c_iflag) |
598 (new->c_iflag & ~lock->c_iflag);
599 new->c_oflag = (old->c_oflag & lock->c_oflag) |
600 (new->c_oflag & ~lock->c_oflag);
601 new->c_cflag = (old->c_cflag & lock->c_cflag) |
602 (new->c_cflag & ~lock->c_cflag);
603 new->c_lflag = (old->c_lflag & lock->c_lflag) |
604 (new->c_lflag & ~lock->c_lflag);
605 for (cc = 0; cc < NCCS; ++cc)
606 if (lock->c_cc[cc])
607 new->c_cc[cc] = old->c_cc[cc];
608 if (lock->c_ispeed)
609 new->c_ispeed = old->c_ispeed;
610 if (lock->c_ospeed)
611 new->c_ospeed = old->c_ospeed;
612 }
613
614 error = tty_ioctl(tp, cmd, data, fflag, td);
615 done: tty_unlock(tp);
616
617 return (error);
618 }
619
620 static int
ttydev_poll(struct cdev * dev,int events,struct thread * td)621 ttydev_poll(struct cdev *dev, int events, struct thread *td)
622 {
623 struct tty *tp = dev->si_drv1;
624 int error, revents = 0;
625
626 error = ttydev_enter(tp);
627 if (error)
628 return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
629
630 if (events & (POLLIN|POLLRDNORM)) {
631 /* See if we can read something. */
632 if (ttydisc_read_poll(tp) > 0)
633 revents |= events & (POLLIN|POLLRDNORM);
634 }
635
636 if (tp->t_flags & TF_ZOMBIE) {
637 /* Hangup flag on zombie state. */
638 revents |= POLLHUP;
639 } else if (events & (POLLOUT|POLLWRNORM)) {
640 /* See if we can write something. */
641 if (ttydisc_write_poll(tp) > 0)
642 revents |= events & (POLLOUT|POLLWRNORM);
643 }
644
645 if (revents == 0) {
646 if (events & (POLLIN|POLLRDNORM))
647 selrecord(td, &tp->t_inpoll);
648 if (events & (POLLOUT|POLLWRNORM))
649 selrecord(td, &tp->t_outpoll);
650 }
651
652 tty_unlock(tp);
653
654 return (revents);
655 }
656
657 static int
ttydev_mmap(struct cdev * dev,vm_ooffset_t offset,vm_paddr_t * paddr,int nprot,vm_memattr_t * memattr)658 ttydev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
659 int nprot, vm_memattr_t *memattr)
660 {
661 struct tty *tp = dev->si_drv1;
662 int error;
663
664 /* Handle mmap() through the driver. */
665
666 error = ttydev_enter(tp);
667 if (error)
668 return (-1);
669 error = ttydevsw_mmap(tp, offset, paddr, nprot, memattr);
670 tty_unlock(tp);
671
672 return (error);
673 }
674
675 /*
676 * kqueue support.
677 */
678
679 static void
tty_kqops_read_detach(struct knote * kn)680 tty_kqops_read_detach(struct knote *kn)
681 {
682 struct tty *tp = kn->kn_hook;
683
684 knlist_remove(&tp->t_inpoll.si_note, kn, 0);
685 }
686
687 static int
tty_kqops_read_event(struct knote * kn,long hint __unused)688 tty_kqops_read_event(struct knote *kn, long hint __unused)
689 {
690 struct tty *tp = kn->kn_hook;
691
692 tty_lock_assert(tp, MA_OWNED);
693
694 if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
695 kn->kn_flags |= EV_EOF;
696 return (1);
697 } else {
698 kn->kn_data = ttydisc_read_poll(tp);
699 return (kn->kn_data > 0);
700 }
701 }
702
703 static void
tty_kqops_write_detach(struct knote * kn)704 tty_kqops_write_detach(struct knote *kn)
705 {
706 struct tty *tp = kn->kn_hook;
707
708 knlist_remove(&tp->t_outpoll.si_note, kn, 0);
709 }
710
711 static int
tty_kqops_write_event(struct knote * kn,long hint __unused)712 tty_kqops_write_event(struct knote *kn, long hint __unused)
713 {
714 struct tty *tp = kn->kn_hook;
715
716 tty_lock_assert(tp, MA_OWNED);
717
718 if (tty_gone(tp)) {
719 kn->kn_flags |= EV_EOF;
720 return (1);
721 } else {
722 kn->kn_data = ttydisc_write_poll(tp);
723 return (kn->kn_data > 0);
724 }
725 }
726
727 static struct filterops tty_kqops_read = {
728 .f_isfd = 1,
729 .f_detach = tty_kqops_read_detach,
730 .f_event = tty_kqops_read_event,
731 };
732
733 static struct filterops tty_kqops_write = {
734 .f_isfd = 1,
735 .f_detach = tty_kqops_write_detach,
736 .f_event = tty_kqops_write_event,
737 };
738
739 static int
ttydev_kqfilter(struct cdev * dev,struct knote * kn)740 ttydev_kqfilter(struct cdev *dev, struct knote *kn)
741 {
742 struct tty *tp = dev->si_drv1;
743 int error;
744
745 error = ttydev_enter(tp);
746 if (error)
747 return (error);
748
749 switch (kn->kn_filter) {
750 case EVFILT_READ:
751 kn->kn_hook = tp;
752 kn->kn_fop = &tty_kqops_read;
753 knlist_add(&tp->t_inpoll.si_note, kn, 1);
754 break;
755 case EVFILT_WRITE:
756 kn->kn_hook = tp;
757 kn->kn_fop = &tty_kqops_write;
758 knlist_add(&tp->t_outpoll.si_note, kn, 1);
759 break;
760 default:
761 error = EINVAL;
762 break;
763 }
764
765 tty_unlock(tp);
766 return (error);
767 }
768
769 static struct cdevsw ttydev_cdevsw = {
770 .d_version = D_VERSION,
771 .d_open = ttydev_open,
772 .d_close = ttydev_close,
773 .d_read = ttydev_read,
774 .d_write = ttydev_write,
775 .d_ioctl = ttydev_ioctl,
776 .d_kqfilter = ttydev_kqfilter,
777 .d_poll = ttydev_poll,
778 .d_mmap = ttydev_mmap,
779 .d_name = "ttydev",
780 .d_flags = D_TTY,
781 };
782
783 /*
784 * Init/lock-state devices
785 */
786
787 static int
ttyil_open(struct cdev * dev,int oflags __unused,int devtype __unused,struct thread * td)788 ttyil_open(struct cdev *dev, int oflags __unused, int devtype __unused,
789 struct thread *td)
790 {
791 struct tty *tp;
792 int error;
793
794 tp = dev->si_drv1;
795 error = 0;
796 tty_lock(tp);
797 if (tty_gone(tp))
798 error = ENODEV;
799 tty_unlock(tp);
800
801 return (error);
802 }
803
804 static int
ttyil_close(struct cdev * dev __unused,int flag __unused,int mode __unused,struct thread * td __unused)805 ttyil_close(struct cdev *dev __unused, int flag __unused, int mode __unused,
806 struct thread *td __unused)
807 {
808
809 return (0);
810 }
811
812 static int
ttyil_rdwr(struct cdev * dev __unused,struct uio * uio __unused,int ioflag __unused)813 ttyil_rdwr(struct cdev *dev __unused, struct uio *uio __unused,
814 int ioflag __unused)
815 {
816
817 return (ENODEV);
818 }
819
820 static int
ttyil_ioctl(struct cdev * dev,u_long cmd,caddr_t data,int fflag,struct thread * td)821 ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
822 struct thread *td)
823 {
824 struct tty *tp = dev->si_drv1;
825 int error;
826
827 tty_lock(tp);
828 if (tty_gone(tp)) {
829 error = ENODEV;
830 goto done;
831 }
832
833 error = ttydevsw_cioctl(tp, dev2unit(dev), cmd, data, td);
834 if (error != ENOIOCTL)
835 goto done;
836 error = 0;
837
838 switch (cmd) {
839 case TIOCGETA:
840 /* Obtain terminal flags through tcgetattr(). */
841 *(struct termios*)data = *(struct termios*)dev->si_drv2;
842 break;
843 case TIOCSETA:
844 /* Set terminal flags through tcsetattr(). */
845 error = priv_check(td, PRIV_TTY_SETA);
846 if (error)
847 break;
848 *(struct termios*)dev->si_drv2 = *(struct termios*)data;
849 break;
850 case TIOCGETD:
851 *(int *)data = TTYDISC;
852 break;
853 case TIOCGWINSZ:
854 bzero(data, sizeof(struct winsize));
855 break;
856 default:
857 error = ENOTTY;
858 }
859
860 done: tty_unlock(tp);
861 return (error);
862 }
863
864 static struct cdevsw ttyil_cdevsw = {
865 .d_version = D_VERSION,
866 .d_open = ttyil_open,
867 .d_close = ttyil_close,
868 .d_read = ttyil_rdwr,
869 .d_write = ttyil_rdwr,
870 .d_ioctl = ttyil_ioctl,
871 .d_name = "ttyil",
872 .d_flags = D_TTY,
873 };
874
875 static void
tty_init_termios(struct tty * tp)876 tty_init_termios(struct tty *tp)
877 {
878 struct termios *t = &tp->t_termios_init_in;
879
880 t->c_cflag = TTYDEF_CFLAG;
881 t->c_iflag = TTYDEF_IFLAG;
882 t->c_lflag = TTYDEF_LFLAG;
883 t->c_oflag = TTYDEF_OFLAG;
884 t->c_ispeed = TTYDEF_SPEED;
885 t->c_ospeed = TTYDEF_SPEED;
886 memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
887
888 tp->t_termios_init_out = *t;
889 }
890
891 void
tty_init_console(struct tty * tp,speed_t s)892 tty_init_console(struct tty *tp, speed_t s)
893 {
894 struct termios *ti = &tp->t_termios_init_in;
895 struct termios *to = &tp->t_termios_init_out;
896
897 if (s != 0) {
898 ti->c_ispeed = ti->c_ospeed = s;
899 to->c_ispeed = to->c_ospeed = s;
900 }
901
902 ti->c_cflag |= CLOCAL;
903 to->c_cflag |= CLOCAL;
904 }
905
906 /*
907 * Standard device routine implementations, mostly meant for
908 * pseudo-terminal device drivers. When a driver creates a new terminal
909 * device class, missing routines are patched.
910 */
911
912 static int
ttydevsw_defopen(struct tty * tp __unused)913 ttydevsw_defopen(struct tty *tp __unused)
914 {
915
916 return (0);
917 }
918
919 static void
ttydevsw_defclose(struct tty * tp __unused)920 ttydevsw_defclose(struct tty *tp __unused)
921 {
922
923 }
924
925 static void
ttydevsw_defoutwakeup(struct tty * tp __unused)926 ttydevsw_defoutwakeup(struct tty *tp __unused)
927 {
928
929 panic("Terminal device has output, while not implemented");
930 }
931
932 static void
ttydevsw_definwakeup(struct tty * tp __unused)933 ttydevsw_definwakeup(struct tty *tp __unused)
934 {
935
936 }
937
938 static int
ttydevsw_defioctl(struct tty * tp __unused,u_long cmd __unused,caddr_t data __unused,struct thread * td __unused)939 ttydevsw_defioctl(struct tty *tp __unused, u_long cmd __unused,
940 caddr_t data __unused, struct thread *td __unused)
941 {
942
943 return (ENOIOCTL);
944 }
945
946 static int
ttydevsw_defcioctl(struct tty * tp __unused,int unit __unused,u_long cmd __unused,caddr_t data __unused,struct thread * td __unused)947 ttydevsw_defcioctl(struct tty *tp __unused, int unit __unused,
948 u_long cmd __unused, caddr_t data __unused, struct thread *td __unused)
949 {
950
951 return (ENOIOCTL);
952 }
953
954 static int
ttydevsw_defparam(struct tty * tp __unused,struct termios * t)955 ttydevsw_defparam(struct tty *tp __unused, struct termios *t)
956 {
957
958 /*
959 * Allow the baud rate to be adjusted for pseudo-devices, but at
960 * least restrict it to 115200 to prevent excessive buffer
961 * usage. Also disallow 0, to prevent foot shooting.
962 */
963 if (t->c_ispeed < B50)
964 t->c_ispeed = B50;
965 else if (t->c_ispeed > B115200)
966 t->c_ispeed = B115200;
967 if (t->c_ospeed < B50)
968 t->c_ospeed = B50;
969 else if (t->c_ospeed > B115200)
970 t->c_ospeed = B115200;
971 t->c_cflag |= CREAD;
972
973 return (0);
974 }
975
976 static int
ttydevsw_defmodem(struct tty * tp __unused,int sigon __unused,int sigoff __unused)977 ttydevsw_defmodem(struct tty *tp __unused, int sigon __unused,
978 int sigoff __unused)
979 {
980
981 /* Simulate a carrier to make the TTY layer happy. */
982 return (SER_DCD);
983 }
984
985 static int
ttydevsw_defmmap(struct tty * tp __unused,vm_ooffset_t offset __unused,vm_paddr_t * paddr __unused,int nprot __unused,vm_memattr_t * memattr __unused)986 ttydevsw_defmmap(struct tty *tp __unused, vm_ooffset_t offset __unused,
987 vm_paddr_t *paddr __unused, int nprot __unused,
988 vm_memattr_t *memattr __unused)
989 {
990
991 return (-1);
992 }
993
994 static void
ttydevsw_defpktnotify(struct tty * tp __unused,char event __unused)995 ttydevsw_defpktnotify(struct tty *tp __unused, char event __unused)
996 {
997
998 }
999
1000 static void
ttydevsw_deffree(void * softc __unused)1001 ttydevsw_deffree(void *softc __unused)
1002 {
1003
1004 panic("Terminal device freed without a free-handler");
1005 }
1006
1007 static bool
ttydevsw_defbusy(struct tty * tp __unused)1008 ttydevsw_defbusy(struct tty *tp __unused)
1009 {
1010
1011 return (FALSE);
1012 }
1013
1014 /*
1015 * TTY allocation and deallocation. TTY devices can be deallocated when
1016 * the driver doesn't use it anymore, when the TTY isn't a session's
1017 * controlling TTY and when the device node isn't opened through devfs.
1018 */
1019
1020 struct tty *
tty_alloc(struct ttydevsw * tsw,void * sc)1021 tty_alloc(struct ttydevsw *tsw, void *sc)
1022 {
1023
1024 return (tty_alloc_mutex(tsw, sc, NULL));
1025 }
1026
1027 struct tty *
tty_alloc_mutex(struct ttydevsw * tsw,void * sc,struct mtx * mutex)1028 tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
1029 {
1030 struct tty *tp;
1031
1032 /* Make sure the driver defines all routines. */
1033 #define PATCH_FUNC(x) do { \
1034 if (tsw->tsw_ ## x == NULL) \
1035 tsw->tsw_ ## x = ttydevsw_def ## x; \
1036 } while (0)
1037 PATCH_FUNC(open);
1038 PATCH_FUNC(close);
1039 PATCH_FUNC(outwakeup);
1040 PATCH_FUNC(inwakeup);
1041 PATCH_FUNC(ioctl);
1042 PATCH_FUNC(cioctl);
1043 PATCH_FUNC(param);
1044 PATCH_FUNC(modem);
1045 PATCH_FUNC(mmap);
1046 PATCH_FUNC(pktnotify);
1047 PATCH_FUNC(free);
1048 PATCH_FUNC(busy);
1049 #undef PATCH_FUNC
1050
1051 tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
1052 tp->t_devsw = tsw;
1053 tp->t_devswsoftc = sc;
1054 tp->t_flags = tsw->tsw_flags;
1055 tp->t_drainwait = tty_drainwait;
1056
1057 tty_init_termios(tp);
1058
1059 cv_init(&tp->t_inwait, "ttyin");
1060 cv_init(&tp->t_outwait, "ttyout");
1061 cv_init(&tp->t_outserwait, "ttyosr");
1062 cv_init(&tp->t_bgwait, "ttybg");
1063 cv_init(&tp->t_dcdwait, "ttydcd");
1064
1065 /* Allow drivers to use a custom mutex to lock the TTY. */
1066 if (mutex != NULL) {
1067 tp->t_mtx = mutex;
1068 } else {
1069 tp->t_mtx = &tp->t_mtxobj;
1070 mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
1071 }
1072
1073 knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
1074 knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
1075
1076 return (tp);
1077 }
1078
1079 static void
tty_dealloc(void * arg)1080 tty_dealloc(void *arg)
1081 {
1082 struct tty *tp = arg;
1083
1084 /*
1085 * ttyydev_leave() usually frees the i/o queues earlier, but it is
1086 * not always called between queue allocation and here. The queues
1087 * may be allocated by ioctls on a pty control device without the
1088 * corresponding pty slave device ever being open, or after it is
1089 * closed.
1090 */
1091 ttyinq_free(&tp->t_inq);
1092 ttyoutq_free(&tp->t_outq);
1093 seldrain(&tp->t_inpoll);
1094 seldrain(&tp->t_outpoll);
1095 knlist_destroy(&tp->t_inpoll.si_note);
1096 knlist_destroy(&tp->t_outpoll.si_note);
1097
1098 cv_destroy(&tp->t_inwait);
1099 cv_destroy(&tp->t_outwait);
1100 cv_destroy(&tp->t_bgwait);
1101 cv_destroy(&tp->t_dcdwait);
1102 cv_destroy(&tp->t_outserwait);
1103
1104 if (tp->t_mtx == &tp->t_mtxobj)
1105 mtx_destroy(&tp->t_mtxobj);
1106 ttydevsw_free(tp);
1107 free(tp, M_TTY);
1108 }
1109
1110 static void
tty_rel_free(struct tty * tp)1111 tty_rel_free(struct tty *tp)
1112 {
1113 struct cdev *dev;
1114
1115 tty_lock_assert(tp, MA_OWNED);
1116
1117 #define TF_ACTIVITY (TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
1118 if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
1119 /* TTY is still in use. */
1120 tty_unlock(tp);
1121 return;
1122 }
1123
1124 /* Stop asynchronous I/O. */
1125 funsetown(&tp->t_sigio);
1126
1127 /* TTY can be deallocated. */
1128 dev = tp->t_dev;
1129 tp->t_dev = NULL;
1130 tty_unlock(tp);
1131
1132 if (dev != NULL) {
1133 sx_xlock(&tty_list_sx);
1134 TAILQ_REMOVE(&tty_list, tp, t_list);
1135 tty_list_count--;
1136 sx_xunlock(&tty_list_sx);
1137 destroy_dev_sched_cb(dev, tty_dealloc, tp);
1138 }
1139 }
1140
1141 void
tty_rel_pgrp(struct tty * tp,struct pgrp * pg)1142 tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
1143 {
1144
1145 MPASS(tp->t_sessioncnt > 0);
1146 tty_lock_assert(tp, MA_OWNED);
1147
1148 if (tp->t_pgrp == pg)
1149 tp->t_pgrp = NULL;
1150
1151 tty_unlock(tp);
1152 }
1153
1154 void
tty_rel_sess(struct tty * tp,struct session * sess)1155 tty_rel_sess(struct tty *tp, struct session *sess)
1156 {
1157
1158 MPASS(tp->t_sessioncnt > 0);
1159
1160 /* Current session has left. */
1161 if (tp->t_session == sess) {
1162 tp->t_session = NULL;
1163 MPASS(tp->t_pgrp == NULL);
1164 }
1165 tp->t_sessioncnt--;
1166 tty_rel_free(tp);
1167 }
1168
1169 void
tty_rel_gone(struct tty * tp)1170 tty_rel_gone(struct tty *tp)
1171 {
1172
1173 MPASS(!tty_gone(tp));
1174
1175 /* Simulate carrier removal. */
1176 ttydisc_modem(tp, 0);
1177
1178 /* Wake up all blocked threads. */
1179 tty_wakeup(tp, FREAD|FWRITE);
1180 cv_broadcast(&tp->t_bgwait);
1181 cv_broadcast(&tp->t_dcdwait);
1182
1183 tp->t_flags |= TF_GONE;
1184 tty_rel_free(tp);
1185 }
1186
1187 /*
1188 * Exposing information about current TTY's through sysctl
1189 */
1190
1191 static void
tty_to_xtty(struct tty * tp,struct xtty * xt)1192 tty_to_xtty(struct tty *tp, struct xtty *xt)
1193 {
1194
1195 tty_lock_assert(tp, MA_OWNED);
1196
1197 xt->xt_size = sizeof(struct xtty);
1198 xt->xt_insize = ttyinq_getsize(&tp->t_inq);
1199 xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
1200 xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
1201 xt->xt_inlow = tp->t_inlow;
1202 xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
1203 xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
1204 xt->xt_outlow = tp->t_outlow;
1205 xt->xt_column = tp->t_column;
1206 xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
1207 xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
1208 xt->xt_flags = tp->t_flags;
1209 xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : (uint32_t)NODEV;
1210 }
1211
1212 static int
sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)1213 sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
1214 {
1215 unsigned long lsize;
1216 struct xtty *xtlist, *xt;
1217 struct tty *tp;
1218 int error;
1219
1220 sx_slock(&tty_list_sx);
1221 lsize = tty_list_count * sizeof(struct xtty);
1222 if (lsize == 0) {
1223 sx_sunlock(&tty_list_sx);
1224 return (0);
1225 }
1226
1227 xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
1228
1229 TAILQ_FOREACH(tp, &tty_list, t_list) {
1230 tty_lock(tp);
1231 tty_to_xtty(tp, xt);
1232 tty_unlock(tp);
1233 xt++;
1234 }
1235 sx_sunlock(&tty_list_sx);
1236
1237 error = SYSCTL_OUT(req, xtlist, lsize);
1238 free(xtlist, M_TTY);
1239 return (error);
1240 }
1241
1242 SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
1243 0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
1244
1245 /*
1246 * Device node creation. Device has been set up, now we can expose it to
1247 * the user.
1248 */
1249
1250 int
tty_makedevf(struct tty * tp,struct ucred * cred,int flags,const char * fmt,...)1251 tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
1252 const char *fmt, ...)
1253 {
1254 va_list ap;
1255 struct make_dev_args args;
1256 struct cdev *dev, *init, *lock, *cua, *cinit, *clock;
1257 const char *prefix = "tty";
1258 char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
1259 uid_t uid;
1260 gid_t gid;
1261 mode_t mode;
1262 int error;
1263
1264 /* Remove "tty" prefix from devices like PTY's. */
1265 if (tp->t_flags & TF_NOPREFIX)
1266 prefix = "";
1267
1268 va_start(ap, fmt);
1269 vsnrprintf(name, sizeof name, 32, fmt, ap);
1270 va_end(ap);
1271
1272 if (cred == NULL) {
1273 /* System device. */
1274 uid = UID_ROOT;
1275 gid = GID_WHEEL;
1276 mode = S_IRUSR|S_IWUSR;
1277 } else {
1278 /* User device. */
1279 uid = cred->cr_ruid;
1280 gid = GID_TTY;
1281 mode = S_IRUSR|S_IWUSR|S_IWGRP;
1282 }
1283
1284 flags = flags & TTYMK_CLONING ? MAKEDEV_REF : 0;
1285 flags |= MAKEDEV_CHECKNAME;
1286
1287 /* Master call-in device. */
1288 make_dev_args_init(&args);
1289 args.mda_flags = flags;
1290 args.mda_devsw = &ttydev_cdevsw;
1291 args.mda_cr = cred;
1292 args.mda_uid = uid;
1293 args.mda_gid = gid;
1294 args.mda_mode = mode;
1295 args.mda_si_drv1 = tp;
1296 error = make_dev_s(&args, &dev, "%s%s", prefix, name);
1297 if (error != 0)
1298 return (error);
1299 tp->t_dev = dev;
1300
1301 init = lock = cua = cinit = clock = NULL;
1302
1303 /* Slave call-in devices. */
1304 if (tp->t_flags & TF_INITLOCK) {
1305 args.mda_devsw = &ttyil_cdevsw;
1306 args.mda_unit = TTYUNIT_INIT;
1307 args.mda_si_drv1 = tp;
1308 args.mda_si_drv2 = &tp->t_termios_init_in;
1309 error = make_dev_s(&args, &init, "%s%s.init", prefix, name);
1310 if (error != 0)
1311 goto fail;
1312 dev_depends(dev, init);
1313
1314 args.mda_unit = TTYUNIT_LOCK;
1315 args.mda_si_drv2 = &tp->t_termios_lock_in;
1316 error = make_dev_s(&args, &lock, "%s%s.lock", prefix, name);
1317 if (error != 0)
1318 goto fail;
1319 dev_depends(dev, lock);
1320 }
1321
1322 /* Call-out devices. */
1323 if (tp->t_flags & TF_CALLOUT) {
1324 make_dev_args_init(&args);
1325 args.mda_flags = flags;
1326 args.mda_devsw = &ttydev_cdevsw;
1327 args.mda_cr = cred;
1328 args.mda_uid = UID_UUCP;
1329 args.mda_gid = GID_DIALER;
1330 args.mda_mode = 0660;
1331 args.mda_unit = TTYUNIT_CALLOUT;
1332 args.mda_si_drv1 = tp;
1333 error = make_dev_s(&args, &cua, "cua%s", name);
1334 if (error != 0)
1335 goto fail;
1336 dev_depends(dev, cua);
1337
1338 /* Slave call-out devices. */
1339 if (tp->t_flags & TF_INITLOCK) {
1340 args.mda_devsw = &ttyil_cdevsw;
1341 args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_INIT;
1342 args.mda_si_drv2 = &tp->t_termios_init_out;
1343 error = make_dev_s(&args, &cinit, "cua%s.init", name);
1344 if (error != 0)
1345 goto fail;
1346 dev_depends(dev, cinit);
1347
1348 args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_LOCK;
1349 args.mda_si_drv2 = &tp->t_termios_lock_out;
1350 error = make_dev_s(&args, &clock, "cua%s.lock", name);
1351 if (error != 0)
1352 goto fail;
1353 dev_depends(dev, clock);
1354 }
1355 }
1356
1357 sx_xlock(&tty_list_sx);
1358 TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
1359 tty_list_count++;
1360 sx_xunlock(&tty_list_sx);
1361
1362 return (0);
1363
1364 fail:
1365 destroy_dev(dev);
1366 if (init)
1367 destroy_dev(init);
1368 if (lock)
1369 destroy_dev(lock);
1370 if (cinit)
1371 destroy_dev(cinit);
1372 if (clock)
1373 destroy_dev(clock);
1374
1375 return (error);
1376 }
1377
1378 /*
1379 * Signalling processes.
1380 */
1381
1382 void
tty_signal_sessleader(struct tty * tp,int sig)1383 tty_signal_sessleader(struct tty *tp, int sig)
1384 {
1385 struct proc *p;
1386
1387 tty_lock_assert(tp, MA_OWNED);
1388 MPASS(sig >= 1 && sig < NSIG);
1389
1390 /* Make signals start output again. */
1391 tp->t_flags &= ~TF_STOPPED;
1392
1393 if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
1394 p = tp->t_session->s_leader;
1395 PROC_LOCK(p);
1396 kern_psignal(p, sig);
1397 PROC_UNLOCK(p);
1398 }
1399 }
1400
1401 void
tty_signal_pgrp(struct tty * tp,int sig)1402 tty_signal_pgrp(struct tty *tp, int sig)
1403 {
1404 ksiginfo_t ksi;
1405
1406 tty_lock_assert(tp, MA_OWNED);
1407 MPASS(sig >= 1 && sig < NSIG);
1408
1409 /* Make signals start output again. */
1410 tp->t_flags &= ~TF_STOPPED;
1411
1412 if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
1413 tty_info(tp);
1414 if (tp->t_pgrp != NULL) {
1415 ksiginfo_init(&ksi);
1416 ksi.ksi_signo = sig;
1417 ksi.ksi_code = SI_KERNEL;
1418 PGRP_LOCK(tp->t_pgrp);
1419 pgsignal(tp->t_pgrp, sig, 1, &ksi);
1420 PGRP_UNLOCK(tp->t_pgrp);
1421 }
1422 }
1423
1424 void
tty_wakeup(struct tty * tp,int flags)1425 tty_wakeup(struct tty *tp, int flags)
1426 {
1427
1428 if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
1429 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
1430
1431 if (flags & FWRITE) {
1432 cv_broadcast(&tp->t_outwait);
1433 selwakeup(&tp->t_outpoll);
1434 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
1435 }
1436 if (flags & FREAD) {
1437 cv_broadcast(&tp->t_inwait);
1438 selwakeup(&tp->t_inpoll);
1439 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
1440 }
1441 }
1442
1443 int
tty_wait(struct tty * tp,struct cv * cv)1444 tty_wait(struct tty *tp, struct cv *cv)
1445 {
1446 int error;
1447 int revokecnt = tp->t_revokecnt;
1448
1449 tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1450 MPASS(!tty_gone(tp));
1451
1452 error = cv_wait_sig(cv, tp->t_mtx);
1453
1454 /* Bail out when the device slipped away. */
1455 if (tty_gone(tp))
1456 return (ENXIO);
1457
1458 /* Restart the system call when we may have been revoked. */
1459 if (tp->t_revokecnt != revokecnt)
1460 return (ERESTART);
1461
1462 return (error);
1463 }
1464
1465 int
tty_timedwait(struct tty * tp,struct cv * cv,int hz)1466 tty_timedwait(struct tty *tp, struct cv *cv, int hz)
1467 {
1468 int error;
1469 int revokecnt = tp->t_revokecnt;
1470
1471 tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1472 MPASS(!tty_gone(tp));
1473
1474 error = cv_timedwait_sig(cv, tp->t_mtx, hz);
1475
1476 /* Bail out when the device slipped away. */
1477 if (tty_gone(tp))
1478 return (ENXIO);
1479
1480 /* Restart the system call when we may have been revoked. */
1481 if (tp->t_revokecnt != revokecnt)
1482 return (ERESTART);
1483
1484 return (error);
1485 }
1486
1487 void
tty_flush(struct tty * tp,int flags)1488 tty_flush(struct tty *tp, int flags)
1489 {
1490
1491 if (flags & FWRITE) {
1492 tp->t_flags &= ~TF_HIWAT_OUT;
1493 ttyoutq_flush(&tp->t_outq);
1494 tty_wakeup(tp, FWRITE);
1495 if (!tty_gone(tp)) {
1496 ttydevsw_outwakeup(tp);
1497 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
1498 }
1499 }
1500 if (flags & FREAD) {
1501 tty_hiwat_in_unblock(tp);
1502 ttyinq_flush(&tp->t_inq);
1503 tty_wakeup(tp, FREAD);
1504 if (!tty_gone(tp)) {
1505 ttydevsw_inwakeup(tp);
1506 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
1507 }
1508 }
1509 }
1510
1511 void
tty_set_winsize(struct tty * tp,const struct winsize * wsz)1512 tty_set_winsize(struct tty *tp, const struct winsize *wsz)
1513 {
1514
1515 if (memcmp(&tp->t_winsize, wsz, sizeof(*wsz)) == 0)
1516 return;
1517 tp->t_winsize = *wsz;
1518 tty_signal_pgrp(tp, SIGWINCH);
1519 }
1520
1521 static int
tty_generic_ioctl(struct tty * tp,u_long cmd,void * data,int fflag,struct thread * td)1522 tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
1523 struct thread *td)
1524 {
1525 int error;
1526
1527 switch (cmd) {
1528 /*
1529 * Modem commands.
1530 * The SER_* and TIOCM_* flags are the same, but one bit
1531 * shifted. I don't know why.
1532 */
1533 case TIOCSDTR:
1534 ttydevsw_modem(tp, SER_DTR, 0);
1535 return (0);
1536 case TIOCCDTR:
1537 ttydevsw_modem(tp, 0, SER_DTR);
1538 return (0);
1539 case TIOCMSET: {
1540 int bits = *(int *)data;
1541 ttydevsw_modem(tp,
1542 (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
1543 ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1544 return (0);
1545 }
1546 case TIOCMBIS: {
1547 int bits = *(int *)data;
1548 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
1549 return (0);
1550 }
1551 case TIOCMBIC: {
1552 int bits = *(int *)data;
1553 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1554 return (0);
1555 }
1556 case TIOCMGET:
1557 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
1558 return (0);
1559
1560 case FIOASYNC:
1561 if (*(int *)data)
1562 tp->t_flags |= TF_ASYNC;
1563 else
1564 tp->t_flags &= ~TF_ASYNC;
1565 return (0);
1566 case FIONBIO:
1567 /* This device supports non-blocking operation. */
1568 return (0);
1569 case FIONREAD:
1570 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
1571 return (0);
1572 case FIONWRITE:
1573 case TIOCOUTQ:
1574 *(int *)data = ttyoutq_bytesused(&tp->t_outq);
1575 return (0);
1576 case FIOSETOWN:
1577 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1578 /* Not allowed to set ownership. */
1579 return (ENOTTY);
1580
1581 /* Temporarily unlock the TTY to set ownership. */
1582 tty_unlock(tp);
1583 error = fsetown(*(int *)data, &tp->t_sigio);
1584 tty_lock(tp);
1585 return (error);
1586 case FIOGETOWN:
1587 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1588 /* Not allowed to set ownership. */
1589 return (ENOTTY);
1590
1591 /* Get ownership. */
1592 *(int *)data = fgetown(&tp->t_sigio);
1593 return (0);
1594 case TIOCGETA:
1595 /* Obtain terminal flags through tcgetattr(). */
1596 *(struct termios*)data = tp->t_termios;
1597 return (0);
1598 case TIOCSETA:
1599 case TIOCSETAW:
1600 case TIOCSETAF: {
1601 struct termios *t = data;
1602
1603 /*
1604 * Who makes up these funny rules? According to POSIX,
1605 * input baud rate is set equal to the output baud rate
1606 * when zero.
1607 */
1608 if (t->c_ispeed == 0)
1609 t->c_ispeed = t->c_ospeed;
1610
1611 /* Discard any unsupported bits. */
1612 t->c_iflag &= TTYSUP_IFLAG;
1613 t->c_oflag &= TTYSUP_OFLAG;
1614 t->c_lflag &= TTYSUP_LFLAG;
1615 t->c_cflag &= TTYSUP_CFLAG;
1616
1617 /* Set terminal flags through tcsetattr(). */
1618 if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
1619 error = tty_drain(tp, 0);
1620 if (error)
1621 return (error);
1622 if (cmd == TIOCSETAF)
1623 tty_flush(tp, FREAD);
1624 }
1625
1626 /*
1627 * Only call param() when the flags really change.
1628 */
1629 if ((t->c_cflag & CIGNORE) == 0 &&
1630 (tp->t_termios.c_cflag != t->c_cflag ||
1631 ((tp->t_termios.c_iflag ^ t->c_iflag) &
1632 (IXON|IXOFF|IXANY)) ||
1633 tp->t_termios.c_ispeed != t->c_ispeed ||
1634 tp->t_termios.c_ospeed != t->c_ospeed)) {
1635 error = ttydevsw_param(tp, t);
1636 if (error)
1637 return (error);
1638
1639 /* XXX: CLOCAL? */
1640
1641 tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
1642 tp->t_termios.c_ispeed = t->c_ispeed;
1643 tp->t_termios.c_ospeed = t->c_ospeed;
1644
1645 /* Baud rate has changed - update watermarks. */
1646 error = tty_watermarks(tp);
1647 if (error)
1648 return (error);
1649 }
1650
1651 /* Copy new non-device driver parameters. */
1652 tp->t_termios.c_iflag = t->c_iflag;
1653 tp->t_termios.c_oflag = t->c_oflag;
1654 tp->t_termios.c_lflag = t->c_lflag;
1655 memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
1656
1657 ttydisc_optimize(tp);
1658
1659 if ((t->c_lflag & ICANON) == 0) {
1660 /*
1661 * When in non-canonical mode, wake up all
1662 * readers. Canonicalize any partial input. VMIN
1663 * and VTIME could also be adjusted.
1664 */
1665 ttyinq_canonicalize(&tp->t_inq);
1666 tty_wakeup(tp, FREAD);
1667 }
1668
1669 /*
1670 * For packet mode: notify the PTY consumer that VSTOP
1671 * and VSTART may have been changed.
1672 */
1673 if (tp->t_termios.c_iflag & IXON &&
1674 tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
1675 tp->t_termios.c_cc[VSTART] == CTRL('Q'))
1676 ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
1677 else
1678 ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
1679 return (0);
1680 }
1681 case TIOCGETD:
1682 /* For compatibility - we only support TTYDISC. */
1683 *(int *)data = TTYDISC;
1684 return (0);
1685 case TIOCGPGRP:
1686 if (!tty_is_ctty(tp, td->td_proc))
1687 return (ENOTTY);
1688
1689 if (tp->t_pgrp != NULL)
1690 *(int *)data = tp->t_pgrp->pg_id;
1691 else
1692 *(int *)data = NO_PID;
1693 return (0);
1694 case TIOCGSID:
1695 if (!tty_is_ctty(tp, td->td_proc))
1696 return (ENOTTY);
1697
1698 MPASS(tp->t_session);
1699 *(int *)data = tp->t_session->s_sid;
1700 return (0);
1701 case TIOCSCTTY: {
1702 struct proc *p = td->td_proc;
1703
1704 /* XXX: This looks awful. */
1705 tty_unlock(tp);
1706 sx_xlock(&proctree_lock);
1707 tty_lock(tp);
1708
1709 if (!SESS_LEADER(p)) {
1710 /* Only the session leader may do this. */
1711 sx_xunlock(&proctree_lock);
1712 return (EPERM);
1713 }
1714
1715 if (tp->t_session != NULL && tp->t_session == p->p_session) {
1716 /* This is already our controlling TTY. */
1717 sx_xunlock(&proctree_lock);
1718 return (0);
1719 }
1720
1721 if (p->p_session->s_ttyp != NULL ||
1722 (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
1723 tp->t_session->s_ttyvp->v_type != VBAD)) {
1724 /*
1725 * There is already a relation between a TTY and
1726 * a session, or the caller is not the session
1727 * leader.
1728 *
1729 * Allow the TTY to be stolen when the vnode is
1730 * invalid, but the reference to the TTY is
1731 * still active. This allows immediate reuse of
1732 * TTYs of which the session leader has been
1733 * killed or the TTY revoked.
1734 */
1735 sx_xunlock(&proctree_lock);
1736 return (EPERM);
1737 }
1738
1739 /* Connect the session to the TTY. */
1740 tp->t_session = p->p_session;
1741 tp->t_session->s_ttyp = tp;
1742 tp->t_sessioncnt++;
1743 sx_xunlock(&proctree_lock);
1744
1745 /* Assign foreground process group. */
1746 tp->t_pgrp = p->p_pgrp;
1747 PROC_LOCK(p);
1748 p->p_flag |= P_CONTROLT;
1749 PROC_UNLOCK(p);
1750
1751 return (0);
1752 }
1753 case TIOCSPGRP: {
1754 struct pgrp *pg;
1755
1756 /*
1757 * XXX: Temporarily unlock the TTY to locate the process
1758 * group. This code would be lot nicer if we would ever
1759 * decompose proctree_lock.
1760 */
1761 tty_unlock(tp);
1762 sx_slock(&proctree_lock);
1763 pg = pgfind(*(int *)data);
1764 if (pg != NULL)
1765 PGRP_UNLOCK(pg);
1766 if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
1767 sx_sunlock(&proctree_lock);
1768 tty_lock(tp);
1769 return (EPERM);
1770 }
1771 tty_lock(tp);
1772
1773 /*
1774 * Determine if this TTY is the controlling TTY after
1775 * relocking the TTY.
1776 */
1777 if (!tty_is_ctty(tp, td->td_proc)) {
1778 sx_sunlock(&proctree_lock);
1779 return (ENOTTY);
1780 }
1781 tp->t_pgrp = pg;
1782 sx_sunlock(&proctree_lock);
1783
1784 /* Wake up the background process groups. */
1785 cv_broadcast(&tp->t_bgwait);
1786 return (0);
1787 }
1788 case TIOCFLUSH: {
1789 int flags = *(int *)data;
1790
1791 if (flags == 0)
1792 flags = (FREAD|FWRITE);
1793 else
1794 flags &= (FREAD|FWRITE);
1795 tty_flush(tp, flags);
1796 return (0);
1797 }
1798 case TIOCDRAIN:
1799 /* Drain TTY output. */
1800 return tty_drain(tp, 0);
1801 case TIOCGDRAINWAIT:
1802 *(int *)data = tp->t_drainwait;
1803 return (0);
1804 case TIOCSDRAINWAIT:
1805 error = priv_check(td, PRIV_TTY_DRAINWAIT);
1806 if (error == 0)
1807 tp->t_drainwait = *(int *)data;
1808 return (error);
1809 case TIOCCONS:
1810 /* Set terminal as console TTY. */
1811 if (*(int *)data) {
1812 error = priv_check(td, PRIV_TTY_CONSOLE);
1813 if (error)
1814 return (error);
1815
1816 /*
1817 * XXX: constty should really need to be locked!
1818 * XXX: allow disconnected constty's to be stolen!
1819 */
1820
1821 if (constty == tp)
1822 return (0);
1823 if (constty != NULL)
1824 return (EBUSY);
1825
1826 tty_unlock(tp);
1827 constty_set(tp);
1828 tty_lock(tp);
1829 } else if (constty == tp) {
1830 constty_clear();
1831 }
1832 return (0);
1833 case TIOCGWINSZ:
1834 /* Obtain window size. */
1835 *(struct winsize*)data = tp->t_winsize;
1836 return (0);
1837 case TIOCSWINSZ:
1838 /* Set window size. */
1839 tty_set_winsize(tp, data);
1840 return (0);
1841 case TIOCEXCL:
1842 tp->t_flags |= TF_EXCLUDE;
1843 return (0);
1844 case TIOCNXCL:
1845 tp->t_flags &= ~TF_EXCLUDE;
1846 return (0);
1847 case TIOCSTOP:
1848 tp->t_flags |= TF_STOPPED;
1849 ttydevsw_pktnotify(tp, TIOCPKT_STOP);
1850 return (0);
1851 case TIOCSTART:
1852 tp->t_flags &= ~TF_STOPPED;
1853 ttydevsw_outwakeup(tp);
1854 ttydevsw_pktnotify(tp, TIOCPKT_START);
1855 return (0);
1856 case TIOCSTAT:
1857 tty_info(tp);
1858 return (0);
1859 case TIOCSTI:
1860 if ((fflag & FREAD) == 0 && priv_check(td, PRIV_TTY_STI))
1861 return (EPERM);
1862 if (!tty_is_ctty(tp, td->td_proc) &&
1863 priv_check(td, PRIV_TTY_STI))
1864 return (EACCES);
1865 ttydisc_rint(tp, *(char *)data, 0);
1866 ttydisc_rint_done(tp);
1867 return (0);
1868 }
1869
1870 #ifdef COMPAT_43TTY
1871 return tty_ioctl_compat(tp, cmd, data, fflag, td);
1872 #else /* !COMPAT_43TTY */
1873 return (ENOIOCTL);
1874 #endif /* COMPAT_43TTY */
1875 }
1876
1877 int
tty_ioctl(struct tty * tp,u_long cmd,void * data,int fflag,struct thread * td)1878 tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag, struct thread *td)
1879 {
1880 int error;
1881
1882 tty_lock_assert(tp, MA_OWNED);
1883
1884 if (tty_gone(tp))
1885 return (ENXIO);
1886
1887 error = ttydevsw_ioctl(tp, cmd, data, td);
1888 if (error == ENOIOCTL)
1889 error = tty_generic_ioctl(tp, cmd, data, fflag, td);
1890
1891 return (error);
1892 }
1893
1894 dev_t
tty_udev(struct tty * tp)1895 tty_udev(struct tty *tp)
1896 {
1897
1898 if (tp->t_dev)
1899 return (dev2udev(tp->t_dev));
1900 else
1901 return (NODEV);
1902 }
1903
1904 int
tty_checkoutq(struct tty * tp)1905 tty_checkoutq(struct tty *tp)
1906 {
1907
1908 /* 256 bytes should be enough to print a log message. */
1909 return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
1910 }
1911
1912 void
tty_hiwat_in_block(struct tty * tp)1913 tty_hiwat_in_block(struct tty *tp)
1914 {
1915
1916 if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
1917 tp->t_termios.c_iflag & IXOFF &&
1918 tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
1919 /*
1920 * Input flow control. Only enter the high watermark when we
1921 * can successfully store the VSTOP character.
1922 */
1923 if (ttyoutq_write_nofrag(&tp->t_outq,
1924 &tp->t_termios.c_cc[VSTOP], 1) == 0)
1925 tp->t_flags |= TF_HIWAT_IN;
1926 } else {
1927 /* No input flow control. */
1928 tp->t_flags |= TF_HIWAT_IN;
1929 }
1930 }
1931
1932 void
tty_hiwat_in_unblock(struct tty * tp)1933 tty_hiwat_in_unblock(struct tty *tp)
1934 {
1935
1936 if (tp->t_flags & TF_HIWAT_IN &&
1937 tp->t_termios.c_iflag & IXOFF &&
1938 tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
1939 /*
1940 * Input flow control. Only leave the high watermark when we
1941 * can successfully store the VSTART character.
1942 */
1943 if (ttyoutq_write_nofrag(&tp->t_outq,
1944 &tp->t_termios.c_cc[VSTART], 1) == 0)
1945 tp->t_flags &= ~TF_HIWAT_IN;
1946 } else {
1947 /* No input flow control. */
1948 tp->t_flags &= ~TF_HIWAT_IN;
1949 }
1950
1951 if (!tty_gone(tp))
1952 ttydevsw_inwakeup(tp);
1953 }
1954
1955 /*
1956 * TTY hooks interface.
1957 */
1958
1959 static int
ttyhook_defrint(struct tty * tp,char c,int flags)1960 ttyhook_defrint(struct tty *tp, char c, int flags)
1961 {
1962
1963 if (ttyhook_rint_bypass(tp, &c, 1) != 1)
1964 return (-1);
1965
1966 return (0);
1967 }
1968
1969 int
ttyhook_register(struct tty ** rtp,struct proc * p,int fd,struct ttyhook * th,void * softc)1970 ttyhook_register(struct tty **rtp, struct proc *p, int fd, struct ttyhook *th,
1971 void *softc)
1972 {
1973 struct tty *tp;
1974 struct file *fp;
1975 struct cdev *dev;
1976 struct cdevsw *cdp;
1977 struct filedesc *fdp;
1978 cap_rights_t rights;
1979 int error, ref;
1980
1981 /* Validate the file descriptor. */
1982 fdp = p->p_fd;
1983 error = fget_unlocked(fdp, fd, cap_rights_init(&rights, CAP_TTYHOOK),
1984 &fp, NULL);
1985 if (error != 0)
1986 return (error);
1987 if (fp->f_ops == &badfileops) {
1988 error = EBADF;
1989 goto done1;
1990 }
1991
1992 /*
1993 * Make sure the vnode is bound to a character device.
1994 * Unlocked check for the vnode type is ok there, because we
1995 * only shall prevent calling devvn_refthread on the file that
1996 * never has been opened over a character device.
1997 */
1998 if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
1999 error = EINVAL;
2000 goto done1;
2001 }
2002
2003 /* Make sure it is a TTY. */
2004 cdp = devvn_refthread(fp->f_vnode, &dev, &ref);
2005 if (cdp == NULL) {
2006 error = ENXIO;
2007 goto done1;
2008 }
2009 if (dev != fp->f_data) {
2010 error = ENXIO;
2011 goto done2;
2012 }
2013 if (cdp != &ttydev_cdevsw) {
2014 error = ENOTTY;
2015 goto done2;
2016 }
2017 tp = dev->si_drv1;
2018
2019 /* Try to attach the hook to the TTY. */
2020 error = EBUSY;
2021 tty_lock(tp);
2022 MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
2023 if (tp->t_flags & TF_HOOK)
2024 goto done3;
2025
2026 tp->t_flags |= TF_HOOK;
2027 tp->t_hook = th;
2028 tp->t_hooksoftc = softc;
2029 *rtp = tp;
2030 error = 0;
2031
2032 /* Maybe we can switch into bypass mode now. */
2033 ttydisc_optimize(tp);
2034
2035 /* Silently convert rint() calls to rint_bypass() when possible. */
2036 if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
2037 th->th_rint = ttyhook_defrint;
2038
2039 done3: tty_unlock(tp);
2040 done2: dev_relthread(dev, ref);
2041 done1: fdrop(fp, curthread);
2042 return (error);
2043 }
2044
2045 void
ttyhook_unregister(struct tty * tp)2046 ttyhook_unregister(struct tty *tp)
2047 {
2048
2049 tty_lock_assert(tp, MA_OWNED);
2050 MPASS(tp->t_flags & TF_HOOK);
2051
2052 /* Disconnect the hook. */
2053 tp->t_flags &= ~TF_HOOK;
2054 tp->t_hook = NULL;
2055
2056 /* Maybe we need to leave bypass mode. */
2057 ttydisc_optimize(tp);
2058
2059 /* Maybe deallocate the TTY as well. */
2060 tty_rel_free(tp);
2061 }
2062
2063 /*
2064 * /dev/console handling.
2065 */
2066
2067 static int
ttyconsdev_open(struct cdev * dev,int oflags,int devtype,struct thread * td)2068 ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
2069 {
2070 struct tty *tp;
2071
2072 /* System has no console device. */
2073 if (dev_console_filename == NULL)
2074 return (ENXIO);
2075
2076 /* Look up corresponding TTY by device name. */
2077 sx_slock(&tty_list_sx);
2078 TAILQ_FOREACH(tp, &tty_list, t_list) {
2079 if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
2080 dev_console->si_drv1 = tp;
2081 break;
2082 }
2083 }
2084 sx_sunlock(&tty_list_sx);
2085
2086 /* System console has no TTY associated. */
2087 if (dev_console->si_drv1 == NULL)
2088 return (ENXIO);
2089
2090 return (ttydev_open(dev, oflags, devtype, td));
2091 }
2092
2093 static int
ttyconsdev_write(struct cdev * dev,struct uio * uio,int ioflag)2094 ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
2095 {
2096
2097 log_console(uio);
2098
2099 return (ttydev_write(dev, uio, ioflag));
2100 }
2101
2102 /*
2103 * /dev/console is a little different than normal TTY's. When opened,
2104 * it determines which TTY to use. When data gets written to it, it
2105 * will be logged in the kernel message buffer.
2106 */
2107 static struct cdevsw ttyconsdev_cdevsw = {
2108 .d_version = D_VERSION,
2109 .d_open = ttyconsdev_open,
2110 .d_close = ttydev_close,
2111 .d_read = ttydev_read,
2112 .d_write = ttyconsdev_write,
2113 .d_ioctl = ttydev_ioctl,
2114 .d_kqfilter = ttydev_kqfilter,
2115 .d_poll = ttydev_poll,
2116 .d_mmap = ttydev_mmap,
2117 .d_name = "ttyconsdev",
2118 .d_flags = D_TTY,
2119 };
2120
2121 static void
ttyconsdev_init(void * unused __unused)2122 ttyconsdev_init(void *unused __unused)
2123 {
2124
2125 dev_console = make_dev_credf(MAKEDEV_ETERNAL, &ttyconsdev_cdevsw, 0,
2126 NULL, UID_ROOT, GID_WHEEL, 0600, "console");
2127 }
2128
2129 SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
2130
2131 void
ttyconsdev_select(const char * name)2132 ttyconsdev_select(const char *name)
2133 {
2134
2135 dev_console_filename = name;
2136 }
2137
2138 /*
2139 * Debugging routines.
2140 */
2141
2142 #include "opt_ddb.h"
2143 #ifdef DDB
2144 #include <ddb/ddb.h>
2145 #include <ddb/db_sym.h>
2146
2147 static const struct {
2148 int flag;
2149 char val;
2150 } ttystates[] = {
2151 #if 0
2152 { TF_NOPREFIX, 'N' },
2153 #endif
2154 { TF_INITLOCK, 'I' },
2155 { TF_CALLOUT, 'C' },
2156
2157 /* Keep these together -> 'Oi' and 'Oo'. */
2158 { TF_OPENED, 'O' },
2159 { TF_OPENED_IN, 'i' },
2160 { TF_OPENED_OUT, 'o' },
2161 { TF_OPENED_CONS, 'c' },
2162
2163 { TF_GONE, 'G' },
2164 { TF_OPENCLOSE, 'B' },
2165 { TF_ASYNC, 'Y' },
2166 { TF_LITERAL, 'L' },
2167
2168 /* Keep these together -> 'Hi' and 'Ho'. */
2169 { TF_HIWAT, 'H' },
2170 { TF_HIWAT_IN, 'i' },
2171 { TF_HIWAT_OUT, 'o' },
2172
2173 { TF_STOPPED, 'S' },
2174 { TF_EXCLUDE, 'X' },
2175 { TF_BYPASS, 'l' },
2176 { TF_ZOMBIE, 'Z' },
2177 { TF_HOOK, 's' },
2178
2179 /* Keep these together -> 'bi' and 'bo'. */
2180 { TF_BUSY, 'b' },
2181 { TF_BUSY_IN, 'i' },
2182 { TF_BUSY_OUT, 'o' },
2183
2184 { 0, '\0'},
2185 };
2186
2187 #define TTY_FLAG_BITS \
2188 "\20\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN" \
2189 "\5OPENED_OUT\6OPENED_CONS\7GONE\10OPENCLOSE" \
2190 "\11ASYNC\12LITERAL\13HIWAT_IN\14HIWAT_OUT" \
2191 "\15STOPPED\16EXCLUDE\17BYPASS\20ZOMBIE" \
2192 "\21HOOK\22BUSY_IN\23BUSY_OUT"
2193
2194 #define DB_PRINTSYM(name, addr) \
2195 db_printf("%s " #name ": ", sep); \
2196 db_printsym((db_addr_t) addr, DB_STGY_ANY); \
2197 db_printf("\n");
2198
2199 static void
_db_show_devsw(const char * sep,const struct ttydevsw * tsw)2200 _db_show_devsw(const char *sep, const struct ttydevsw *tsw)
2201 {
2202
2203 db_printf("%sdevsw: ", sep);
2204 db_printsym((db_addr_t)tsw, DB_STGY_ANY);
2205 db_printf(" (%p)\n", tsw);
2206 DB_PRINTSYM(open, tsw->tsw_open);
2207 DB_PRINTSYM(close, tsw->tsw_close);
2208 DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
2209 DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
2210 DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
2211 DB_PRINTSYM(param, tsw->tsw_param);
2212 DB_PRINTSYM(modem, tsw->tsw_modem);
2213 DB_PRINTSYM(mmap, tsw->tsw_mmap);
2214 DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
2215 DB_PRINTSYM(free, tsw->tsw_free);
2216 }
2217
2218 static void
_db_show_hooks(const char * sep,const struct ttyhook * th)2219 _db_show_hooks(const char *sep, const struct ttyhook *th)
2220 {
2221
2222 db_printf("%shook: ", sep);
2223 db_printsym((db_addr_t)th, DB_STGY_ANY);
2224 db_printf(" (%p)\n", th);
2225 if (th == NULL)
2226 return;
2227 DB_PRINTSYM(rint, th->th_rint);
2228 DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
2229 DB_PRINTSYM(rint_done, th->th_rint_done);
2230 DB_PRINTSYM(rint_poll, th->th_rint_poll);
2231 DB_PRINTSYM(getc_inject, th->th_getc_inject);
2232 DB_PRINTSYM(getc_capture, th->th_getc_capture);
2233 DB_PRINTSYM(getc_poll, th->th_getc_poll);
2234 DB_PRINTSYM(close, th->th_close);
2235 }
2236
2237 static void
_db_show_termios(const char * name,const struct termios * t)2238 _db_show_termios(const char *name, const struct termios *t)
2239 {
2240
2241 db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
2242 "lflag 0x%x ispeed %u ospeed %u\n", name,
2243 t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
2244 t->c_ispeed, t->c_ospeed);
2245 }
2246
2247 /* DDB command to show TTY statistics. */
DB_SHOW_COMMAND(tty,db_show_tty)2248 DB_SHOW_COMMAND(tty, db_show_tty)
2249 {
2250 struct tty *tp;
2251
2252 if (!have_addr) {
2253 db_printf("usage: show tty <addr>\n");
2254 return;
2255 }
2256 tp = (struct tty *)addr;
2257
2258 db_printf("%p: %s\n", tp, tty_devname(tp));
2259 db_printf("\tmtx: %p\n", tp->t_mtx);
2260 db_printf("\tflags: 0x%b\n", tp->t_flags, TTY_FLAG_BITS);
2261 db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
2262
2263 /* Buffering mechanisms. */
2264 db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
2265 "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
2266 tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
2267 tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
2268 db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
2269 &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
2270 tp->t_outq.to_nblocks, tp->t_outq.to_quota);
2271 db_printf("\tinlow: %zu\n", tp->t_inlow);
2272 db_printf("\toutlow: %zu\n", tp->t_outlow);
2273 _db_show_termios("\ttermios", &tp->t_termios);
2274 db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
2275 tp->t_winsize.ws_row, tp->t_winsize.ws_col,
2276 tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
2277 db_printf("\tcolumn: %u\n", tp->t_column);
2278 db_printf("\twritepos: %u\n", tp->t_writepos);
2279 db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
2280
2281 /* Init/lock-state devices. */
2282 _db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
2283 _db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
2284 _db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
2285 _db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
2286
2287 /* Hooks */
2288 _db_show_devsw("\t", tp->t_devsw);
2289 _db_show_hooks("\t", tp->t_hook);
2290
2291 /* Process info. */
2292 db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
2293 tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
2294 tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
2295 db_printf("\tsession: %p", tp->t_session);
2296 if (tp->t_session != NULL)
2297 db_printf(" count %u leader %p tty %p sid %d login %s",
2298 tp->t_session->s_count, tp->t_session->s_leader,
2299 tp->t_session->s_ttyp, tp->t_session->s_sid,
2300 tp->t_session->s_login);
2301 db_printf("\n");
2302 db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
2303 db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
2304 db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
2305 db_printf("\tdev: %p\n", tp->t_dev);
2306 }
2307
2308 /* DDB command to list TTYs. */
DB_SHOW_ALL_COMMAND(ttys,db_show_all_ttys)2309 DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
2310 {
2311 struct tty *tp;
2312 size_t isiz, osiz;
2313 int i, j;
2314
2315 /* Make the output look like `pstat -t'. */
2316 db_printf("PTR ");
2317 #if defined(__LP64__)
2318 db_printf(" ");
2319 #endif
2320 db_printf(" LINE INQ CAN LIN LOW OUTQ USE LOW "
2321 "COL SESS PGID STATE\n");
2322
2323 TAILQ_FOREACH(tp, &tty_list, t_list) {
2324 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
2325 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
2326
2327 db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d "
2328 "%5d ", tp, tty_devname(tp), isiz,
2329 tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
2330 tp->t_inq.ti_end - tp->t_inq.ti_linestart,
2331 isiz - tp->t_inlow, osiz,
2332 tp->t_outq.to_end - tp->t_outq.to_begin,
2333 osiz - tp->t_outlow, MIN(tp->t_column, 99999),
2334 tp->t_session ? tp->t_session->s_sid : 0,
2335 tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
2336
2337 /* Flag bits. */
2338 for (i = j = 0; ttystates[i].flag; i++)
2339 if (tp->t_flags & ttystates[i].flag) {
2340 db_printf("%c", ttystates[i].val);
2341 j++;
2342 }
2343 if (j == 0)
2344 db_printf("-");
2345 db_printf("\n");
2346 }
2347 }
2348 #endif /* DDB */
2349