sys/kern/tty.c

   1 /*-
   2  * Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Portions of this software were developed under sponsorship from Snow
   6  * B.V., the Netherlands.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include <sys/cdefs.h>
  31 __FBSDID("$FreeBSD$");
  32
  33 #include "opt_capsicum.h"
  34 #include "opt_compat.h"
  35
  36 #include <sys/param.h>
  37 #include <sys/capsicum.h>
  38 #include <sys/conf.h>
  39 #include <sys/cons.h>
  40 #include <sys/fcntl.h>
  41 #include <sys/file.h>
  42 #include <sys/filedesc.h>
  43 #include <sys/filio.h>
  44 #ifdef COMPAT_43TTY
  45 #include <sys/ioctl_compat.h>
  46 #endif /* COMPAT_43TTY */
  47 #include <sys/kernel.h>
  48 #include <sys/limits.h>
  49 #include <sys/malloc.h>
  50 #include <sys/mount.h>
  51 #include <sys/poll.h>
  52 #include <sys/priv.h>
  53 #include <sys/proc.h>
  54 #include <sys/serial.h>
  55 #include <sys/signal.h>
  56 #include <sys/stat.h>
  57 #include <sys/sx.h>
  58 #include <sys/sysctl.h>
  59 #include <sys/systm.h>
  60 #include <sys/tty.h>
  61 #include <sys/ttycom.h>
  62 #define TTYDEFCHARS
  63 #include <sys/ttydefaults.h>
  64 #undef TTYDEFCHARS
  65 #include <sys/ucred.h>
  66 #include <sys/vnode.h>
  67
  68 #include <machine/stdarg.h>
  69
  70 static MALLOC_DEFINE(M_TTY, "tty", "tty device");
  71
  72 static void tty_rel_free(struct tty *tp);
  73
  74 static TAILQ_HEAD(, tty) tty_list = TAILQ_HEAD_INITIALIZER(tty_list);
  75 static struct sx tty_list_sx;
  76 SX_SYSINIT(tty_list, &tty_list_sx, "tty list");
  77 static unsigned int tty_list_count = 0;
  78
  79 /* Character device of /dev/console. */
  80 static struct cdev      *dev_console;
  81 static const char       *dev_console_filename;
  82
  83 /*
  84  * Flags that are supported and stored by this implementation.
  85  */
  86 #define TTYSUP_IFLAG    (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK|ISTRIP|\
  87                         INLCR|IGNCR|ICRNL|IXON|IXOFF|IXANY|IMAXBEL)
  88 #define TTYSUP_OFLAG    (OPOST|ONLCR|TAB3|ONOEOT|OCRNL|ONOCR|ONLRET)
  89 #define TTYSUP_LFLAG    (ECHOKE|ECHOE|ECHOK|ECHO|ECHONL|ECHOPRT|\
  90                         ECHOCTL|ISIG|ICANON|ALTWERASE|IEXTEN|TOSTOP|\
  91                         FLUSHO|NOKERNINFO|NOFLSH)
  92 #define TTYSUP_CFLAG    (CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\
  93                         HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\
  94                         CDSR_OFLOW|CCAR_OFLOW)
  95
  96 #define TTY_CALLOUT(tp,d) (dev2unit(d) & TTYUNIT_CALLOUT)
  97
  98 /*
  99  * Set TTY buffer sizes.
 100  */
 101
 102 #define TTYBUF_MAX      65536
 103
 104 static void
 105 tty_watermarks(struct tty *tp)
 106 {
 107         size_t bs = 0;
 108
 109         /* Provide an input buffer for 0.2 seconds of data. */
 110         if (tp->t_termios.c_cflag & CREAD)
 111                 bs = MIN(tp->t_termios.c_ispeed / 5, TTYBUF_MAX);
 112         ttyinq_setsize(&tp->t_inq, tp, bs);
 113
 114         /* Set low watermark at 10% (when 90% is available). */
 115         tp->t_inlow = (ttyinq_getallocatedsize(&tp->t_inq) * 9) / 10;
 116
 117         /* Provide an output buffer for 0.2 seconds of data. */
 118         bs = MIN(tp->t_termios.c_ospeed / 5, TTYBUF_MAX);
 119         ttyoutq_setsize(&tp->t_outq, tp, bs);
 120
 121         /* Set low watermark at 10% (when 90% is available). */
 122         tp->t_outlow = (ttyoutq_getallocatedsize(&tp->t_outq) * 9) / 10;
 123 }
 124
 125 static int
 126 tty_drain(struct tty *tp, int leaving)
 127 {
 128         size_t bytesused;
 129         int error;
 130
 131         if (ttyhook_hashook(tp, getc_inject))
 132                 /* buffer is inaccessible */
 133                 return (0);
 134
 135         while (ttyoutq_bytesused(&tp->t_outq) > 0 || ttydevsw_busy(tp)) {
 136                 ttydevsw_outwakeup(tp);
 137                 /* Could be handled synchronously. */
 138                 bytesused = ttyoutq_bytesused(&tp->t_outq);
 139                 if (bytesused == 0 && !ttydevsw_busy(tp))
 140                         return (0);
 141
 142                 /* Wait for data to be drained. */
 143                 if (leaving) {
 144                         error = tty_timedwait(tp, &tp->t_outwait, hz);
 145                         if (error == EWOULDBLOCK &&
 146                             ttyoutq_bytesused(&tp->t_outq) < bytesused)
 147                                 error = 0;
 148                 } else
 149                         error = tty_wait(tp, &tp->t_outwait);
 150
 151                 if (error)
 152                         return (error);
 153         }
 154
 155         return (0);
 156 }
 157
 158 /*
 159  * Though ttydev_enter() and ttydev_leave() seem to be related, they
 160  * don't have to be used together. ttydev_enter() is used by the cdev
 161  * operations to prevent an actual operation from being processed when
 162  * the TTY has been abandoned. ttydev_leave() is used by ttydev_open()
 163  * and ttydev_close() to determine whether per-TTY data should be
 164  * deallocated.
 165  */
 166
 167 static __inline int
 168 ttydev_enter(struct tty *tp)
 169 {
 170
 171         tty_lock(tp);
 172
 173         if (tty_gone(tp) || !tty_opened(tp)) {
 174                 /* Device is already gone. */
 175                 tty_unlock(tp);
 176                 return (ENXIO);
 177         }
 178
 179         return (0);
 180 }
 181
 182 static void
 183 ttydev_leave(struct tty *tp)
 184 {
 185
 186         tty_lock_assert(tp, MA_OWNED);
 187
 188         if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
 189                 /* Device is still opened somewhere. */
 190                 tty_unlock(tp);
 191                 return;
 192         }
 193
 194         tp->t_flags |= TF_OPENCLOSE;
 195
 196         /* Stop asynchronous I/O. */
 197         funsetown(&tp->t_sigio);
 198
 199         /* Remove console TTY. */
 200         if (constty == tp)
 201                 constty_clear();
 202
 203         /* Drain any output. */
 204         if (!tty_gone(tp))
 205                 tty_drain(tp, 1);
 206
 207         ttydisc_close(tp);
 208
 209         /* Free i/o queues now since they might be large. */
 210         ttyinq_free(&tp->t_inq);
 211         tp->t_inlow = 0;
 212         ttyoutq_free(&tp->t_outq);
 213         tp->t_outlow = 0;
 214
 215         knlist_clear(&tp->t_inpoll.si_note, 1);
 216         knlist_clear(&tp->t_outpoll.si_note, 1);
 217
 218         if (!tty_gone(tp))
 219                 ttydevsw_close(tp);
 220
 221         tp->t_flags &= ~TF_OPENCLOSE;
 222         cv_broadcast(&tp->t_dcdwait);
 223         tty_rel_free(tp);
 224 }
 225
 226 /*
 227  * Operations that are exposed through the character device in /dev.
 228  */
 229 static int
 230 ttydev_open(struct cdev *dev, int oflags, int devtype __unused,
 231     struct thread *td)
 232 {
 233         struct tty *tp;
 234         int error;
 235
 236         tp = dev->si_drv1;
 237         error = 0;
 238         tty_lock(tp);
 239         if (tty_gone(tp)) {
 240                 /* Device is already gone. */
 241                 tty_unlock(tp);
 242                 return (ENXIO);
 243         }
 244
 245         /*
 246          * Block when other processes are currently opening or closing
 247          * the TTY.
 248          */
 249         while (tp->t_flags & TF_OPENCLOSE) {
 250                 error = tty_wait(tp, &tp->t_dcdwait);
 251                 if (error != 0) {
 252                         tty_unlock(tp);
 253                         return (error);
 254                 }
 255         }
 256         tp->t_flags |= TF_OPENCLOSE;
 257
 258         /*
 259          * Make sure the "tty" and "cua" device cannot be opened at the
 260          * same time.  The console is a "tty" device.
 261          */
 262         if (TTY_CALLOUT(tp, dev)) {
 263                 if (tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) {
 264                         error = EBUSY;
 265                         goto done;
 266                 }
 267         } else {
 268                 if (tp->t_flags & TF_OPENED_OUT) {
 269                         error = EBUSY;
 270                         goto done;
 271                 }
 272         }
 273
 274         if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
 275                 error = EBUSY;
 276                 goto done;
 277         }
 278
 279         if (!tty_opened(tp)) {
 280                 /* Set proper termios flags. */
 281                 if (TTY_CALLOUT(tp, dev))
 282                         tp->t_termios = tp->t_termios_init_out;
 283                 else
 284                         tp->t_termios = tp->t_termios_init_in;
 285                 ttydevsw_param(tp, &tp->t_termios);
 286                 /* Prevent modem control on callout devices and /dev/console. */
 287                 if (TTY_CALLOUT(tp, dev) || dev == dev_console)
 288                         tp->t_termios.c_cflag |= CLOCAL;
 289
 290                 ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
 291
 292                 error = ttydevsw_open(tp);
 293                 if (error != 0)
 294                         goto done;
 295
 296                 ttydisc_open(tp);
 297                 tty_watermarks(tp); /* XXXGL: drops lock */
 298         }
 299
 300         /* Wait for Carrier Detect. */
 301         if ((oflags & O_NONBLOCK) == 0 &&
 302             (tp->t_termios.c_cflag & CLOCAL) == 0) {
 303                 while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
 304                         error = tty_wait(tp, &tp->t_dcdwait);
 305                         if (error != 0)
 306                                 goto done;
 307                 }
 308         }
 309
 310         if (dev == dev_console)
 311                 tp->t_flags |= TF_OPENED_CONS;
 312         else if (TTY_CALLOUT(tp, dev))
 313                 tp->t_flags |= TF_OPENED_OUT;
 314         else
 315                 tp->t_flags |= TF_OPENED_IN;
 316         MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
 317             (tp->t_flags & TF_OPENED_OUT) == 0);
 318
 319 done:   tp->t_flags &= ~TF_OPENCLOSE;
 320         cv_broadcast(&tp->t_dcdwait);
 321         ttydev_leave(tp);
 322
 323         return (error);
 324 }
 325
 326 static int
 327 ttydev_close(struct cdev *dev, int fflag, int devtype __unused,
 328     struct thread *td __unused)
 329 {
 330         struct tty *tp = dev->si_drv1;
 331
 332         tty_lock(tp);
 333
 334         /*
 335          * Don't actually close the device if it is being used as the
 336          * console.
 337          */
 338         MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
 339             (tp->t_flags & TF_OPENED_OUT) == 0);
 340         if (dev == dev_console)
 341                 tp->t_flags &= ~TF_OPENED_CONS;
 342         else
 343                 tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
 344
 345         if (tp->t_flags & TF_OPENED) {
 346                 tty_unlock(tp);
 347                 return (0);
 348         }
 349
 350         /* If revoking, flush output now to avoid draining it later. */
 351         if (fflag & FREVOKE)
 352                 tty_flush(tp, FWRITE);
 353
 354         tp->t_flags &= ~TF_EXCLUDE;
 355
 356         /* Properly wake up threads that are stuck - revoke(). */
 357         tp->t_revokecnt++;
 358         tty_wakeup(tp, FREAD|FWRITE);
 359         cv_broadcast(&tp->t_bgwait);
 360         cv_broadcast(&tp->t_dcdwait);
 361
 362         ttydev_leave(tp);
 363
 364         return (0);
 365 }
 366
 367 static __inline int
 368 tty_is_ctty(struct tty *tp, struct proc *p)
 369 {
 370
 371         tty_lock_assert(tp, MA_OWNED);
 372
 373         return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
 374 }
 375
 376 int
 377 tty_wait_background(struct tty *tp, struct thread *td, int sig)
 378 {
 379         struct proc *p = td->td_proc;
 380         struct pgrp *pg;
 381         ksiginfo_t ksi;
 382         int error;
 383
 384         MPASS(sig == SIGTTIN || sig == SIGTTOU);
 385         tty_lock_assert(tp, MA_OWNED);
 386
 387         for (;;) {
 388                 PROC_LOCK(p);
 389                 /*
 390                  * The process should only sleep, when:
 391                  * - This terminal is the controlling terminal
 392                  * - Its process group is not the foreground process
 393                  *   group
 394                  * - The parent process isn't waiting for the child to
 395                  *   exit
 396                  * - the signal to send to the process isn't masked
 397                  */
 398                 if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
 399                         /* Allow the action to happen. */
 400                         PROC_UNLOCK(p);
 401                         return (0);
 402                 }
 403
 404                 if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
 405                     SIGISMEMBER(td->td_sigmask, sig)) {
 406                         /* Only allow them in write()/ioctl(). */
 407                         PROC_UNLOCK(p);
 408                         return (sig == SIGTTOU ? 0 : EIO);
 409                 }
 410
 411                 pg = p->p_pgrp;
 412                 if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
 413                         /* Don't allow the action to happen. */
 414                         PROC_UNLOCK(p);
 415                         return (EIO);
 416                 }
 417                 PROC_UNLOCK(p);
 418
 419                 /*
 420                  * Send the signal and sleep until we're the new
 421                  * foreground process group.
 422                  */
 423                 if (sig != 0) {
 424                         ksiginfo_init(&ksi);
 425                         ksi.ksi_code = SI_KERNEL;
 426                         ksi.ksi_signo = sig;
 427                         sig = 0;
 428                 }
 429                 PGRP_LOCK(pg);
 430                 pgsignal(pg, ksi.ksi_signo, 1, &ksi);
 431                 PGRP_UNLOCK(pg);
 432
 433                 error = tty_wait(tp, &tp->t_bgwait);
 434                 if (error)
 435                         return (error);
 436         }
 437 }
 438
 439 static int
 440 ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
 441 {
 442         struct tty *tp = dev->si_drv1;
 443         int error;
 444
 445         error = ttydev_enter(tp);
 446         if (error)
 447                 goto done;
 448         error = ttydisc_read(tp, uio, ioflag);
 449         tty_unlock(tp);
 450
 451         /*
 452          * The read() call should not throw an error when the device is
 453          * being destroyed. Silently convert it to an EOF.
 454          */
 455 done:   if (error == ENXIO)
 456                 error = 0;
 457         return (error);
 458 }
 459
 460 static int
 461 ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
 462 {
 463         struct tty *tp = dev->si_drv1;
 464         int error;
 465
 466         error = ttydev_enter(tp);
 467         if (error)
 468                 return (error);
 469
 470         if (tp->t_termios.c_lflag & TOSTOP) {
 471                 error = tty_wait_background(tp, curthread, SIGTTOU);
 472                 if (error)
 473                         goto done;
 474         }
 475
 476         if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
 477                 /* Allow non-blocking writes to bypass serialization. */
 478                 error = ttydisc_write(tp, uio, ioflag);
 479         } else {
 480                 /* Serialize write() calls. */
 481                 while (tp->t_flags & TF_BUSY_OUT) {
 482                         error = tty_wait(tp, &tp->t_outserwait);
 483                         if (error)
 484                                 goto done;
 485                 }
 486
 487                 tp->t_flags |= TF_BUSY_OUT;
 488                 error = ttydisc_write(tp, uio, ioflag);
 489                 tp->t_flags &= ~TF_BUSY_OUT;
 490                 cv_signal(&tp->t_outserwait);
 491         }
 492
 493 done:   tty_unlock(tp);
 494         return (error);
 495 }
 496
 497 static int
 498 ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 499     struct thread *td)
 500 {
 501         struct tty *tp = dev->si_drv1;
 502         int error;
 503
 504         error = ttydev_enter(tp);
 505         if (error)
 506                 return (error);
 507
 508         switch (cmd) {
 509         case TIOCCBRK:
 510         case TIOCCONS:
 511         case TIOCDRAIN:
 512         case TIOCEXCL:
 513         case TIOCFLUSH:
 514         case TIOCNXCL:
 515         case TIOCSBRK:
 516         case TIOCSCTTY:
 517         case TIOCSETA:
 518         case TIOCSETAF:
 519         case TIOCSETAW:
 520         case TIOCSPGRP:
 521         case TIOCSTART:
 522         case TIOCSTAT:
 523         case TIOCSTI:
 524         case TIOCSTOP:
 525         case TIOCSWINSZ:
 526 #if 0
 527         case TIOCSDRAINWAIT:
 528         case TIOCSETD:
 529 #endif
 530 #ifdef COMPAT_43TTY
 531         case  TIOCLBIC:
 532         case  TIOCLBIS:
 533         case  TIOCLSET:
 534         case  TIOCSETC:
 535         case OTIOCSETD:
 536         case  TIOCSETN:
 537         case  TIOCSETP:
 538         case  TIOCSLTC:
 539 #endif /* COMPAT_43TTY */
 540                 /*
 541                  * If the ioctl() causes the TTY to be modified, let it
 542                  * wait in the background.
 543                  */
 544                 error = tty_wait_background(tp, curthread, SIGTTOU);
 545                 if (error)
 546                         goto done;
 547         }
 548
 549         if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
 550                 struct termios *old = &tp->t_termios;
 551                 struct termios *new = (struct termios *)data;
 552                 struct termios *lock = TTY_CALLOUT(tp, dev) ?
 553                     &tp->t_termios_lock_out : &tp->t_termios_lock_in;
 554                 int cc;
 555
 556                 /*
 557                  * Lock state devices.  Just overwrite the values of the
 558                  * commands that are currently in use.
 559                  */
 560                 new->c_iflag = (old->c_iflag & lock->c_iflag) |
 561                     (new->c_iflag & ~lock->c_iflag);
 562                 new->c_oflag = (old->c_oflag & lock->c_oflag) |
 563                     (new->c_oflag & ~lock->c_oflag);
 564                 new->c_cflag = (old->c_cflag & lock->c_cflag) |
 565                     (new->c_cflag & ~lock->c_cflag);
 566                 new->c_lflag = (old->c_lflag & lock->c_lflag) |
 567                     (new->c_lflag & ~lock->c_lflag);
 568                 for (cc = 0; cc < NCCS; ++cc)
 569                         if (lock->c_cc[cc])
 570                                 new->c_cc[cc] = old->c_cc[cc];
 571                 if (lock->c_ispeed)
 572                         new->c_ispeed = old->c_ispeed;
 573                 if (lock->c_ospeed)
 574                         new->c_ospeed = old->c_ospeed;
 575         }
 576
 577         error = tty_ioctl(tp, cmd, data, fflag, td);
 578 done:   tty_unlock(tp);
 579
 580         return (error);
 581 }
 582
 583 static int
 584 ttydev_poll(struct cdev *dev, int events, struct thread *td)
 585 {
 586         struct tty *tp = dev->si_drv1;
 587         int error, revents = 0;
 588
 589         error = ttydev_enter(tp);
 590         if (error)
 591                 return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
 592
 593         if (events & (POLLIN|POLLRDNORM)) {
 594                 /* See if we can read something. */
 595                 if (ttydisc_read_poll(tp) > 0)
 596                         revents |= events & (POLLIN|POLLRDNORM);
 597         }
 598
 599         if (tp->t_flags & TF_ZOMBIE) {
 600                 /* Hangup flag on zombie state. */
 601                 revents |= POLLHUP;
 602         } else if (events & (POLLOUT|POLLWRNORM)) {
 603                 /* See if we can write something. */
 604                 if (ttydisc_write_poll(tp) > 0)
 605                         revents |= events & (POLLOUT|POLLWRNORM);
 606         }
 607
 608         if (revents == 0) {
 609                 if (events & (POLLIN|POLLRDNORM))
 610                         selrecord(td, &tp->t_inpoll);
 611                 if (events & (POLLOUT|POLLWRNORM))
 612                         selrecord(td, &tp->t_outpoll);
 613         }
 614
 615         tty_unlock(tp);
 616
 617         return (revents);
 618 }
 619
 620 static int
 621 ttydev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
 622     int nprot, vm_memattr_t *memattr)
 623 {
 624         struct tty *tp = dev->si_drv1;
 625         int error;
 626
 627         /* Handle mmap() through the driver. */
 628
 629         error = ttydev_enter(tp);
 630         if (error)
 631                 return (-1);
 632         error = ttydevsw_mmap(tp, offset, paddr, nprot, memattr);
 633         tty_unlock(tp);
 634
 635         return (error);
 636 }
 637
 638 /*
 639  * kqueue support.
 640  */
 641
 642 static void
 643 tty_kqops_read_detach(struct knote *kn)
 644 {
 645         struct tty *tp = kn->kn_hook;
 646
 647         knlist_remove(&tp->t_inpoll.si_note, kn, 0);
 648 }
 649
 650 static int
 651 tty_kqops_read_event(struct knote *kn, long hint __unused)
 652 {
 653         struct tty *tp = kn->kn_hook;
 654
 655         tty_lock_assert(tp, MA_OWNED);
 656
 657         if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
 658                 kn->kn_flags |= EV_EOF;
 659                 return (1);
 660         } else {
 661                 kn->kn_data = ttydisc_read_poll(tp);
 662                 return (kn->kn_data > 0);
 663         }
 664 }
 665
 666 static void
 667 tty_kqops_write_detach(struct knote *kn)
 668 {
 669         struct tty *tp = kn->kn_hook;
 670
 671         knlist_remove(&tp->t_outpoll.si_note, kn, 0);
 672 }
 673
 674 static int
 675 tty_kqops_write_event(struct knote *kn, long hint __unused)
 676 {
 677         struct tty *tp = kn->kn_hook;
 678
 679         tty_lock_assert(tp, MA_OWNED);
 680
 681         if (tty_gone(tp)) {
 682                 kn->kn_flags |= EV_EOF;
 683                 return (1);
 684         } else {
 685                 kn->kn_data = ttydisc_write_poll(tp);
 686                 return (kn->kn_data > 0);
 687         }
 688 }
 689
 690 static struct filterops tty_kqops_read = {
 691         .f_isfd = 1,
 692         .f_detach = tty_kqops_read_detach,
 693         .f_event = tty_kqops_read_event,
 694 };
 695
 696 static struct filterops tty_kqops_write = {
 697         .f_isfd = 1,
 698         .f_detach = tty_kqops_write_detach,
 699         .f_event = tty_kqops_write_event,
 700 };
 701
 702 static int
 703 ttydev_kqfilter(struct cdev *dev, struct knote *kn)
 704 {
 705         struct tty *tp = dev->si_drv1;
 706         int error;
 707
 708         error = ttydev_enter(tp);
 709         if (error)
 710                 return (error);
 711
 712         switch (kn->kn_filter) {
 713         case EVFILT_READ:
 714                 kn->kn_hook = tp;
 715                 kn->kn_fop = &tty_kqops_read;
 716                 knlist_add(&tp->t_inpoll.si_note, kn, 1);
 717                 break;
 718         case EVFILT_WRITE:
 719                 kn->kn_hook = tp;
 720                 kn->kn_fop = &tty_kqops_write;
 721                 knlist_add(&tp->t_outpoll.si_note, kn, 1);
 722                 break;
 723         default:
 724                 error = EINVAL;
 725                 break;
 726         }
 727
 728         tty_unlock(tp);
 729         return (error);
 730 }
 731
 732 static struct cdevsw ttydev_cdevsw = {
 733         .d_version      = D_VERSION,
 734         .d_open         = ttydev_open,
 735         .d_close        = ttydev_close,
 736         .d_read         = ttydev_read,
 737         .d_write        = ttydev_write,
 738         .d_ioctl        = ttydev_ioctl,
 739         .d_kqfilter     = ttydev_kqfilter,
 740         .d_poll         = ttydev_poll,
 741         .d_mmap         = ttydev_mmap,
 742         .d_name         = "ttydev",
 743         .d_flags        = D_TTY,
 744 };
 745
 746 /*
 747  * Init/lock-state devices
 748  */
 749
 750 static int
 751 ttyil_open(struct cdev *dev, int oflags __unused, int devtype __unused,
 752     struct thread *td)
 753 {
 754         struct tty *tp;
 755         int error;
 756
 757         tp = dev->si_drv1;
 758         error = 0;
 759         tty_lock(tp);
 760         if (tty_gone(tp))
 761                 error = ENODEV;
 762         tty_unlock(tp);
 763
 764         return (error);
 765 }
 766
 767 static int
 768 ttyil_close(struct cdev *dev __unused, int flag __unused, int mode __unused,
 769     struct thread *td __unused)
 770 {
 771
 772         return (0);
 773 }
 774
 775 static int
 776 ttyil_rdwr(struct cdev *dev __unused, struct uio *uio __unused,
 777     int ioflag __unused)
 778 {
 779
 780         return (ENODEV);
 781 }
 782
 783 static int
 784 ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 785     struct thread *td)
 786 {
 787         struct tty *tp = dev->si_drv1;
 788         int error;
 789
 790         tty_lock(tp);
 791         if (tty_gone(tp)) {
 792                 error = ENODEV;
 793                 goto done;
 794         }
 795
 796         error = ttydevsw_cioctl(tp, dev2unit(dev), cmd, data, td);
 797         if (error != ENOIOCTL)
 798                 goto done;
 799         error = 0;
 800
 801         switch (cmd) {
 802         case TIOCGETA:
 803                 /* Obtain terminal flags through tcgetattr(). */
 804                 *(struct termios*)data = *(struct termios*)dev->si_drv2;
 805                 break;
 806         case TIOCSETA:
 807                 /* Set terminal flags through tcsetattr(). */
 808                 error = priv_check(td, PRIV_TTY_SETA);
 809                 if (error)
 810                         break;
 811                 *(struct termios*)dev->si_drv2 = *(struct termios*)data;
 812                 break;
 813         case TIOCGETD:
 814                 *(int *)data = TTYDISC;
 815                 break;
 816         case TIOCGWINSZ:
 817                 bzero(data, sizeof(struct winsize));
 818                 break;
 819         default:
 820                 error = ENOTTY;
 821         }
 822
 823 done:   tty_unlock(tp);
 824         return (error);
 825 }
 826
 827 static struct cdevsw ttyil_cdevsw = {
 828         .d_version      = D_VERSION,
 829         .d_open         = ttyil_open,
 830         .d_close        = ttyil_close,
 831         .d_read         = ttyil_rdwr,
 832         .d_write        = ttyil_rdwr,
 833         .d_ioctl        = ttyil_ioctl,
 834         .d_name         = "ttyil",
 835         .d_flags        = D_TTY,
 836 };
 837
 838 static void
 839 tty_init_termios(struct tty *tp)
 840 {
 841         struct termios *t = &tp->t_termios_init_in;
 842
 843         t->c_cflag = TTYDEF_CFLAG;
 844         t->c_iflag = TTYDEF_IFLAG;
 845         t->c_lflag = TTYDEF_LFLAG;
 846         t->c_oflag = TTYDEF_OFLAG;
 847         t->c_ispeed = TTYDEF_SPEED;
 848         t->c_ospeed = TTYDEF_SPEED;
 849         memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
 850
 851         tp->t_termios_init_out = *t;
 852 }
 853
 854 void
 855 tty_init_console(struct tty *tp, speed_t s)
 856 {
 857         struct termios *ti = &tp->t_termios_init_in;
 858         struct termios *to = &tp->t_termios_init_out;
 859
 860         if (s != 0) {
 861                 ti->c_ispeed = ti->c_ospeed = s;
 862                 to->c_ispeed = to->c_ospeed = s;
 863         }
 864
 865         ti->c_cflag |= CLOCAL;
 866         to->c_cflag |= CLOCAL;
 867 }
 868
 869 /*
 870  * Standard device routine implementations, mostly meant for
 871  * pseudo-terminal device drivers. When a driver creates a new terminal
 872  * device class, missing routines are patched.
 873  */
 874
 875 static int
 876 ttydevsw_defopen(struct tty *tp __unused)
 877 {
 878
 879         return (0);
 880 }
 881
 882 static void
 883 ttydevsw_defclose(struct tty *tp __unused)
 884 {
 885
 886 }
 887
 888 static void
 889 ttydevsw_defoutwakeup(struct tty *tp __unused)
 890 {
 891
 892         panic("Terminal device has output, while not implemented");
 893 }
 894
 895 static void
 896 ttydevsw_definwakeup(struct tty *tp __unused)
 897 {
 898
 899 }
 900
 901 static int
 902 ttydevsw_defioctl(struct tty *tp __unused, u_long cmd __unused,
 903     caddr_t data __unused, struct thread *td __unused)
 904 {
 905
 906         return (ENOIOCTL);
 907 }
 908
 909 static int
 910 ttydevsw_defcioctl(struct tty *tp __unused, int unit __unused,
 911     u_long cmd __unused, caddr_t data __unused, struct thread *td __unused)
 912 {
 913
 914         return (ENOIOCTL);
 915 }
 916
 917 static int
 918 ttydevsw_defparam(struct tty *tp __unused, struct termios *t)
 919 {
 920
 921         /*
 922          * Allow the baud rate to be adjusted for pseudo-devices, but at
 923          * least restrict it to 115200 to prevent excessive buffer
 924          * usage.  Also disallow 0, to prevent foot shooting.
 925          */
 926         if (t->c_ispeed < B50)
 927                 t->c_ispeed = B50;
 928         else if (t->c_ispeed > B115200)
 929                 t->c_ispeed = B115200;
 930         if (t->c_ospeed < B50)
 931                 t->c_ospeed = B50;
 932         else if (t->c_ospeed > B115200)
 933                 t->c_ospeed = B115200;
 934         t->c_cflag |= CREAD;
 935
 936         return (0);
 937 }
 938
 939 static int
 940 ttydevsw_defmodem(struct tty *tp __unused, int sigon __unused,
 941     int sigoff __unused)
 942 {
 943
 944         /* Simulate a carrier to make the TTY layer happy. */
 945         return (SER_DCD);
 946 }
 947
 948 static int
 949 ttydevsw_defmmap(struct tty *tp __unused, vm_ooffset_t offset __unused,
 950     vm_paddr_t *paddr __unused, int nprot __unused,
 951     vm_memattr_t *memattr __unused)
 952 {
 953
 954         return (-1);
 955 }
 956
 957 static void
 958 ttydevsw_defpktnotify(struct tty *tp __unused, char event __unused)
 959 {
 960
 961 }
 962
 963 static void
 964 ttydevsw_deffree(void *softc __unused)
 965 {
 966
 967         panic("Terminal device freed without a free-handler");
 968 }
 969
 970 static bool
 971 ttydevsw_defbusy(struct tty *tp __unused)
 972 {
 973
 974         return (FALSE);
 975 }
 976
 977 /*
 978  * TTY allocation and deallocation. TTY devices can be deallocated when
 979  * the driver doesn't use it anymore, when the TTY isn't a session's
 980  * controlling TTY and when the device node isn't opened through devfs.
 981  */
 982
 983 struct tty *
 984 tty_alloc(struct ttydevsw *tsw, void *sc)
 985 {
 986
 987         return (tty_alloc_mutex(tsw, sc, NULL));
 988 }
 989
 990 struct tty *
 991 tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
 992 {
 993         struct tty *tp;
 994
 995         /* Make sure the driver defines all routines. */
 996 #define PATCH_FUNC(x) do {                              \
 997         if (tsw->tsw_ ## x == NULL)                     \
 998                 tsw->tsw_ ## x = ttydevsw_def ## x;     \
 999 } while (0)
1000         PATCH_FUNC(open);
1001         PATCH_FUNC(close);
1002         PATCH_FUNC(outwakeup);
1003         PATCH_FUNC(inwakeup);
1004         PATCH_FUNC(ioctl);
1005         PATCH_FUNC(cioctl);
1006         PATCH_FUNC(param);
1007         PATCH_FUNC(modem);
1008         PATCH_FUNC(mmap);
1009         PATCH_FUNC(pktnotify);
1010         PATCH_FUNC(free);
1011         PATCH_FUNC(busy);
1012 #undef PATCH_FUNC
1013
1014         tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
1015         tp->t_devsw = tsw;
1016         tp->t_devswsoftc = sc;
1017         tp->t_flags = tsw->tsw_flags;
1018
1019         tty_init_termios(tp);
1020
1021         cv_init(&tp->t_inwait, "ttyin");
1022         cv_init(&tp->t_outwait, "ttyout");
1023         cv_init(&tp->t_outserwait, "ttyosr");
1024         cv_init(&tp->t_bgwait, "ttybg");
1025         cv_init(&tp->t_dcdwait, "ttydcd");
1026
1027         /* Allow drivers to use a custom mutex to lock the TTY. */
1028         if (mutex != NULL) {
1029                 tp->t_mtx = mutex;
1030         } else {
1031                 tp->t_mtx = &tp->t_mtxobj;
1032                 mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
1033         }
1034
1035         knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
1036         knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
1037
1038         return (tp);
1039 }
1040
1041 static void
1042 tty_dealloc(void *arg)
1043 {
1044         struct tty *tp = arg;
1045
1046         /*
1047          * ttyydev_leave() usually frees the i/o queues earlier, but it is
1048          * not always called between queue allocation and here.  The queues
1049          * may be allocated by ioctls on a pty control device without the
1050          * corresponding pty slave device ever being open, or after it is
1051          * closed.
1052          */
1053         ttyinq_free(&tp->t_inq);
1054         ttyoutq_free(&tp->t_outq);
1055         seldrain(&tp->t_inpoll);
1056         seldrain(&tp->t_outpoll);
1057         knlist_destroy(&tp->t_inpoll.si_note);
1058         knlist_destroy(&tp->t_outpoll.si_note);
1059
1060         cv_destroy(&tp->t_inwait);
1061         cv_destroy(&tp->t_outwait);
1062         cv_destroy(&tp->t_bgwait);
1063         cv_destroy(&tp->t_dcdwait);
1064         cv_destroy(&tp->t_outserwait);
1065
1066         if (tp->t_mtx == &tp->t_mtxobj)
1067                 mtx_destroy(&tp->t_mtxobj);
1068         ttydevsw_free(tp);
1069         free(tp, M_TTY);
1070 }
1071
1072 static void
1073 tty_rel_free(struct tty *tp)
1074 {
1075         struct cdev *dev;
1076
1077         tty_lock_assert(tp, MA_OWNED);
1078
1079 #define TF_ACTIVITY     (TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
1080         if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
1081                 /* TTY is still in use. */
1082                 tty_unlock(tp);
1083                 return;
1084         }
1085
1086         /* TTY can be deallocated. */
1087         dev = tp->t_dev;
1088         tp->t_dev = NULL;
1089         tty_unlock(tp);
1090
1091         if (dev != NULL) {
1092                 sx_xlock(&tty_list_sx);
1093                 TAILQ_REMOVE(&tty_list, tp, t_list);
1094                 tty_list_count--;
1095                 sx_xunlock(&tty_list_sx);
1096                 destroy_dev_sched_cb(dev, tty_dealloc, tp);
1097         }
1098 }
1099
1100 void
1101 tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
1102 {
1103
1104         MPASS(tp->t_sessioncnt > 0);
1105         tty_lock_assert(tp, MA_OWNED);
1106
1107         if (tp->t_pgrp == pg)
1108                 tp->t_pgrp = NULL;
1109
1110         tty_unlock(tp);
1111 }
1112
1113 void
1114 tty_rel_sess(struct tty *tp, struct session *sess)
1115 {
1116
1117         MPASS(tp->t_sessioncnt > 0);
1118
1119         /* Current session has left. */
1120         if (tp->t_session == sess) {
1121                 tp->t_session = NULL;
1122                 MPASS(tp->t_pgrp == NULL);
1123         }
1124         tp->t_sessioncnt--;
1125         tty_rel_free(tp);
1126 }
1127
1128 void
1129 tty_rel_gone(struct tty *tp)
1130 {
1131
1132         MPASS(!tty_gone(tp));
1133
1134         /* Simulate carrier removal. */
1135         ttydisc_modem(tp, 0);
1136
1137         /* Wake up all blocked threads. */
1138         tty_wakeup(tp, FREAD|FWRITE);
1139         cv_broadcast(&tp->t_bgwait);
1140         cv_broadcast(&tp->t_dcdwait);
1141
1142         tp->t_flags |= TF_GONE;
1143         tty_rel_free(tp);
1144 }
1145
1146 /*
1147  * Exposing information about current TTY's through sysctl
1148  */
1149
1150 static void
1151 tty_to_xtty(struct tty *tp, struct xtty *xt)
1152 {
1153
1154         tty_lock_assert(tp, MA_OWNED);
1155
1156         xt->xt_size = sizeof(struct xtty);
1157         xt->xt_insize = ttyinq_getsize(&tp->t_inq);
1158         xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
1159         xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
1160         xt->xt_inlow = tp->t_inlow;
1161         xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
1162         xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
1163         xt->xt_outlow = tp->t_outlow;
1164         xt->xt_column = tp->t_column;
1165         xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
1166         xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
1167         xt->xt_flags = tp->t_flags;
1168         xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
1169 }
1170
1171 static int
1172 sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
1173 {
1174         unsigned long lsize;
1175         struct xtty *xtlist, *xt;
1176         struct tty *tp;
1177         int error;
1178
1179         sx_slock(&tty_list_sx);
1180         lsize = tty_list_count * sizeof(struct xtty);
1181         if (lsize == 0) {
1182                 sx_sunlock(&tty_list_sx);
1183                 return (0);
1184         }
1185
1186         xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
1187
1188         TAILQ_FOREACH(tp, &tty_list, t_list) {
1189                 tty_lock(tp);
1190                 tty_to_xtty(tp, xt);
1191                 tty_unlock(tp);
1192                 xt++;
1193         }
1194         sx_sunlock(&tty_list_sx);
1195
1196         error = SYSCTL_OUT(req, xtlist, lsize);
1197         free(xtlist, M_TTY);
1198         return (error);
1199 }
1200
1201 SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
1202         0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
1203
1204 /*
1205  * Device node creation. Device has been set up, now we can expose it to
1206  * the user.
1207  */
1208
1209 int
1210 tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
1211     const char *fmt, ...)
1212 {
1213         va_list ap;
1214         struct make_dev_args args;
1215         struct cdev *dev, *init, *lock, *cua, *cinit, *clock;
1216         const char *prefix = "tty";
1217         char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
1218         uid_t uid;
1219         gid_t gid;
1220         mode_t mode;
1221         int error;
1222
1223         /* Remove "tty" prefix from devices like PTY's. */
1224         if (tp->t_flags & TF_NOPREFIX)
1225                 prefix = "";
1226
1227         va_start(ap, fmt);
1228         vsnrprintf(name, sizeof name, 32, fmt, ap);
1229         va_end(ap);
1230
1231         if (cred == NULL) {
1232                 /* System device. */
1233                 uid = UID_ROOT;
1234                 gid = GID_WHEEL;
1235                 mode = S_IRUSR|S_IWUSR;
1236         } else {
1237                 /* User device. */
1238                 uid = cred->cr_ruid;
1239                 gid = GID_TTY;
1240                 mode = S_IRUSR|S_IWUSR|S_IWGRP;
1241         }
1242
1243         flags = flags & TTYMK_CLONING ? MAKEDEV_REF : 0;
1244         flags |= MAKEDEV_CHECKNAME;
1245
1246         /* Master call-in device. */
1247         make_dev_args_init(&args);
1248         args.mda_flags = flags;
1249         args.mda_devsw = &ttydev_cdevsw;
1250         args.mda_cr = cred;
1251         args.mda_uid = uid;
1252         args.mda_gid = gid;
1253         args.mda_mode = mode;
1254         args.mda_si_drv1 = tp;
1255         error = make_dev_s(&args, &dev, "%s%s", prefix, name);
1256         if (error != 0)
1257                 return (error);
1258         tp->t_dev = dev;
1259
1260         init = lock = cua = cinit = clock = NULL;
1261
1262         /* Slave call-in devices. */
1263         if (tp->t_flags & TF_INITLOCK) {
1264                 args.mda_devsw = &ttyil_cdevsw;
1265                 args.mda_unit = TTYUNIT_INIT;
1266                 args.mda_si_drv1 = tp;
1267                 args.mda_si_drv2 = &tp->t_termios_init_in;
1268                 error = make_dev_s(&args, &init, "%s%s.init", prefix, name);
1269                 if (error != 0)
1270                         goto fail;
1271                 dev_depends(dev, init);
1272
1273                 args.mda_unit = TTYUNIT_LOCK;
1274                 args.mda_si_drv2 = &tp->t_termios_lock_in;
1275                 error = make_dev_s(&args, &lock, "%s%s.lock", prefix, name);
1276                 if (error != 0)
1277                         goto fail;
1278                 dev_depends(dev, lock);
1279         }
1280
1281         /* Call-out devices. */
1282         if (tp->t_flags & TF_CALLOUT) {
1283                 make_dev_args_init(&args);
1284                 args.mda_flags = flags;
1285                 args.mda_devsw = &ttydev_cdevsw;
1286                 args.mda_cr = cred;
1287                 args.mda_uid = UID_UUCP;
1288                 args.mda_gid = GID_DIALER;
1289                 args.mda_mode = 0660;
1290                 args.mda_unit = TTYUNIT_CALLOUT;
1291                 args.mda_si_drv1 = tp;
1292                 error = make_dev_s(&args, &cua, "cua%s", name);
1293                 if (error != 0)
1294                         goto fail;
1295                 dev_depends(dev, cua);
1296
1297                 /* Slave call-out devices. */
1298                 if (tp->t_flags & TF_INITLOCK) {
1299                         args.mda_devsw = &ttyil_cdevsw;
1300                         args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_INIT;
1301                         args.mda_si_drv2 = &tp->t_termios_init_out;
1302                         error = make_dev_s(&args, &cinit, "cua%s.init", name);
1303                         if (error != 0)
1304                                 goto fail;
1305                         dev_depends(dev, cinit);
1306
1307                         args.mda_unit = TTYUNIT_CALLOUT | TTYUNIT_LOCK;
1308                         args.mda_si_drv2 = &tp->t_termios_lock_out;
1309                         error = make_dev_s(&args, &clock, "cua%s.lock", name);
1310                         if (error != 0)
1311                                 goto fail;
1312                         dev_depends(dev, clock);
1313                 }
1314         }
1315
1316         sx_xlock(&tty_list_sx);
1317         TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
1318         tty_list_count++;
1319         sx_xunlock(&tty_list_sx);
1320
1321         return (0);
1322
1323 fail:
1324         destroy_dev(dev);
1325         if (init)
1326                 destroy_dev(init);
1327         if (lock)
1328                 destroy_dev(lock);
1329         if (cinit)
1330                 destroy_dev(cinit);
1331         if (clock)
1332                 destroy_dev(clock);
1333
1334         return (error);
1335 }
1336
1337 /*
1338  * Signalling processes.
1339  */
1340
1341 void
1342 tty_signal_sessleader(struct tty *tp, int sig)
1343 {
1344         struct proc *p;
1345
1346         tty_lock_assert(tp, MA_OWNED);
1347         MPASS(sig >= 1 && sig < NSIG);
1348
1349         /* Make signals start output again. */
1350         tp->t_flags &= ~TF_STOPPED;
1351
1352         if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
1353                 p = tp->t_session->s_leader;
1354                 PROC_LOCK(p);
1355                 kern_psignal(p, sig);
1356                 PROC_UNLOCK(p);
1357         }
1358 }
1359
1360 void
1361 tty_signal_pgrp(struct tty *tp, int sig)
1362 {
1363         ksiginfo_t ksi;
1364
1365         tty_lock_assert(tp, MA_OWNED);
1366         MPASS(sig >= 1 && sig < NSIG);
1367
1368         /* Make signals start output again. */
1369         tp->t_flags &= ~TF_STOPPED;
1370
1371         if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
1372                 tty_info(tp);
1373         if (tp->t_pgrp != NULL) {
1374                 ksiginfo_init(&ksi);
1375                 ksi.ksi_signo = sig;
1376                 ksi.ksi_code = SI_KERNEL;
1377                 PGRP_LOCK(tp->t_pgrp);
1378                 pgsignal(tp->t_pgrp, sig, 1, &ksi);
1379                 PGRP_UNLOCK(tp->t_pgrp);
1380         }
1381 }
1382
1383 void
1384 tty_wakeup(struct tty *tp, int flags)
1385 {
1386
1387         if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
1388                 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
1389
1390         if (flags & FWRITE) {
1391                 cv_broadcast(&tp->t_outwait);
1392                 selwakeup(&tp->t_outpoll);
1393                 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
1394         }
1395         if (flags & FREAD) {
1396                 cv_broadcast(&tp->t_inwait);
1397                 selwakeup(&tp->t_inpoll);
1398                 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
1399         }
1400 }
1401
1402 int
1403 tty_wait(struct tty *tp, struct cv *cv)
1404 {
1405         int error;
1406         int revokecnt = tp->t_revokecnt;
1407
1408         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1409         MPASS(!tty_gone(tp));
1410
1411         error = cv_wait_sig(cv, tp->t_mtx);
1412
1413         /* Bail out when the device slipped away. */
1414         if (tty_gone(tp))
1415                 return (ENXIO);
1416
1417         /* Restart the system call when we may have been revoked. */
1418         if (tp->t_revokecnt != revokecnt)
1419                 return (ERESTART);
1420
1421         return (error);
1422 }
1423
1424 int
1425 tty_timedwait(struct tty *tp, struct cv *cv, int hz)
1426 {
1427         int error;
1428         int revokecnt = tp->t_revokecnt;
1429
1430         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1431         MPASS(!tty_gone(tp));
1432
1433         error = cv_timedwait_sig(cv, tp->t_mtx, hz);
1434
1435         /* Bail out when the device slipped away. */
1436         if (tty_gone(tp))
1437                 return (ENXIO);
1438
1439         /* Restart the system call when we may have been revoked. */
1440         if (tp->t_revokecnt != revokecnt)
1441                 return (ERESTART);
1442
1443         return (error);
1444 }
1445
1446 void
1447 tty_flush(struct tty *tp, int flags)
1448 {
1449
1450         if (flags & FWRITE) {
1451                 tp->t_flags &= ~TF_HIWAT_OUT;
1452                 ttyoutq_flush(&tp->t_outq);
1453                 tty_wakeup(tp, FWRITE);
1454                 if (!tty_gone(tp)) {
1455                         ttydevsw_outwakeup(tp);
1456                         ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
1457                 }
1458         }
1459         if (flags & FREAD) {
1460                 tty_hiwat_in_unblock(tp);
1461                 ttyinq_flush(&tp->t_inq);
1462                 tty_wakeup(tp, FREAD);
1463                 if (!tty_gone(tp)) {
1464                         ttydevsw_inwakeup(tp);
1465                         ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
1466                 }
1467         }
1468 }
1469
1470 void
1471 tty_set_winsize(struct tty *tp, const struct winsize *wsz)
1472 {
1473
1474         if (memcmp(&tp->t_winsize, wsz, sizeof(*wsz)) == 0)
1475                 return;
1476         tp->t_winsize = *wsz;
1477         tty_signal_pgrp(tp, SIGWINCH);
1478 }
1479
1480 static int
1481 tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
1482     struct thread *td)
1483 {
1484         int error;
1485
1486         switch (cmd) {
1487         /*
1488          * Modem commands.
1489          * The SER_* and TIOCM_* flags are the same, but one bit
1490          * shifted. I don't know why.
1491          */
1492         case TIOCSDTR:
1493                 ttydevsw_modem(tp, SER_DTR, 0);
1494                 return (0);
1495         case TIOCCDTR:
1496                 ttydevsw_modem(tp, 0, SER_DTR);
1497                 return (0);
1498         case TIOCMSET: {
1499                 int bits = *(int *)data;
1500                 ttydevsw_modem(tp,
1501                     (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
1502                     ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1503                 return (0);
1504         }
1505         case TIOCMBIS: {
1506                 int bits = *(int *)data;
1507                 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
1508                 return (0);
1509         }
1510         case TIOCMBIC: {
1511                 int bits = *(int *)data;
1512                 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1513                 return (0);
1514         }
1515         case TIOCMGET:
1516                 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
1517                 return (0);
1518
1519         case FIOASYNC:
1520                 if (*(int *)data)
1521                         tp->t_flags |= TF_ASYNC;
1522                 else
1523                         tp->t_flags &= ~TF_ASYNC;
1524                 return (0);
1525         case FIONBIO:
1526                 /* This device supports non-blocking operation. */
1527                 return (0);
1528         case FIONREAD:
1529                 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
1530                 return (0);
1531         case FIONWRITE:
1532         case TIOCOUTQ:
1533                 *(int *)data = ttyoutq_bytesused(&tp->t_outq);
1534                 return (0);
1535         case FIOSETOWN:
1536                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1537                         /* Not allowed to set ownership. */
1538                         return (ENOTTY);
1539
1540                 /* Temporarily unlock the TTY to set ownership. */
1541                 tty_unlock(tp);
1542                 error = fsetown(*(int *)data, &tp->t_sigio);
1543                 tty_lock(tp);
1544                 return (error);
1545         case FIOGETOWN:
1546                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1547                         /* Not allowed to set ownership. */
1548                         return (ENOTTY);
1549
1550                 /* Get ownership. */
1551                 *(int *)data = fgetown(&tp->t_sigio);
1552                 return (0);
1553         case TIOCGETA:
1554                 /* Obtain terminal flags through tcgetattr(). */
1555                 *(struct termios*)data = tp->t_termios;
1556                 return (0);
1557         case TIOCSETA:
1558         case TIOCSETAW:
1559         case TIOCSETAF: {
1560                 struct termios *t = data;
1561
1562                 /*
1563                  * Who makes up these funny rules? According to POSIX,
1564                  * input baud rate is set equal to the output baud rate
1565                  * when zero.
1566                  */
1567                 if (t->c_ispeed == 0)
1568                         t->c_ispeed = t->c_ospeed;
1569
1570                 /* Discard any unsupported bits. */
1571                 t->c_iflag &= TTYSUP_IFLAG;
1572                 t->c_oflag &= TTYSUP_OFLAG;
1573                 t->c_lflag &= TTYSUP_LFLAG;
1574                 t->c_cflag &= TTYSUP_CFLAG;
1575
1576                 /* Set terminal flags through tcsetattr(). */
1577                 if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
1578                         error = tty_drain(tp, 0);
1579                         if (error)
1580                                 return (error);
1581                         if (cmd == TIOCSETAF)
1582                                 tty_flush(tp, FREAD);
1583                 }
1584
1585                 /*
1586                  * Only call param() when the flags really change.
1587                  */
1588                 if ((t->c_cflag & CIGNORE) == 0 &&
1589                     (tp->t_termios.c_cflag != t->c_cflag ||
1590                     ((tp->t_termios.c_iflag ^ t->c_iflag) &
1591                     (IXON|IXOFF|IXANY)) ||
1592                     tp->t_termios.c_ispeed != t->c_ispeed ||
1593                     tp->t_termios.c_ospeed != t->c_ospeed)) {
1594                         error = ttydevsw_param(tp, t);
1595                         if (error)
1596                                 return (error);
1597
1598                         /* XXX: CLOCAL? */
1599
1600                         tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
1601                         tp->t_termios.c_ispeed = t->c_ispeed;
1602                         tp->t_termios.c_ospeed = t->c_ospeed;
1603
1604                         /* Baud rate has changed - update watermarks. */
1605                         tty_watermarks(tp);
1606                 }
1607
1608                 /* Copy new non-device driver parameters. */
1609                 tp->t_termios.c_iflag = t->c_iflag;
1610                 tp->t_termios.c_oflag = t->c_oflag;
1611                 tp->t_termios.c_lflag = t->c_lflag;
1612                 memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
1613
1614                 ttydisc_optimize(tp);
1615
1616                 if ((t->c_lflag & ICANON) == 0) {
1617                         /*
1618                          * When in non-canonical mode, wake up all
1619                          * readers. Canonicalize any partial input. VMIN
1620                          * and VTIME could also be adjusted.
1621                          */
1622                         ttyinq_canonicalize(&tp->t_inq);
1623                         tty_wakeup(tp, FREAD);
1624                 }
1625
1626                 /*
1627                  * For packet mode: notify the PTY consumer that VSTOP
1628                  * and VSTART may have been changed.
1629                  */
1630                 if (tp->t_termios.c_iflag & IXON &&
1631                     tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
1632                     tp->t_termios.c_cc[VSTART] == CTRL('Q'))
1633                         ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
1634                 else
1635                         ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
1636                 return (0);
1637         }
1638         case TIOCGETD:
1639                 /* For compatibility - we only support TTYDISC. */
1640                 *(int *)data = TTYDISC;
1641                 return (0);
1642         case TIOCGPGRP:
1643                 if (!tty_is_ctty(tp, td->td_proc))
1644                         return (ENOTTY);
1645
1646                 if (tp->t_pgrp != NULL)
1647                         *(int *)data = tp->t_pgrp->pg_id;
1648                 else
1649                         *(int *)data = NO_PID;
1650                 return (0);
1651         case TIOCGSID:
1652                 if (!tty_is_ctty(tp, td->td_proc))
1653                         return (ENOTTY);
1654
1655                 MPASS(tp->t_session);
1656                 *(int *)data = tp->t_session->s_sid;
1657                 return (0);
1658         case TIOCSCTTY: {
1659                 struct proc *p = td->td_proc;
1660
1661                 /* XXX: This looks awful. */
1662                 tty_unlock(tp);
1663                 sx_xlock(&proctree_lock);
1664                 tty_lock(tp);
1665
1666                 if (!SESS_LEADER(p)) {
1667                         /* Only the session leader may do this. */
1668                         sx_xunlock(&proctree_lock);
1669                         return (EPERM);
1670                 }
1671
1672                 if (tp->t_session != NULL && tp->t_session == p->p_session) {
1673                         /* This is already our controlling TTY. */
1674                         sx_xunlock(&proctree_lock);
1675                         return (0);
1676                 }
1677
1678                 if (p->p_session->s_ttyp != NULL ||
1679                     (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
1680                     tp->t_session->s_ttyvp->v_type != VBAD)) {
1681                         /*
1682                          * There is already a relation between a TTY and
1683                          * a session, or the caller is not the session
1684                          * leader.
1685                          *
1686                          * Allow the TTY to be stolen when the vnode is
1687                          * invalid, but the reference to the TTY is
1688                          * still active.  This allows immediate reuse of
1689                          * TTYs of which the session leader has been
1690                          * killed or the TTY revoked.
1691                          */
1692                         sx_xunlock(&proctree_lock);
1693                         return (EPERM);
1694                 }
1695
1696                 /* Connect the session to the TTY. */
1697                 tp->t_session = p->p_session;
1698                 tp->t_session->s_ttyp = tp;
1699                 tp->t_sessioncnt++;
1700                 sx_xunlock(&proctree_lock);
1701
1702                 /* Assign foreground process group. */
1703                 tp->t_pgrp = p->p_pgrp;
1704                 PROC_LOCK(p);
1705                 p->p_flag |= P_CONTROLT;
1706                 PROC_UNLOCK(p);
1707
1708                 return (0);
1709         }
1710         case TIOCSPGRP: {
1711                 struct pgrp *pg;
1712
1713                 /*
1714                  * XXX: Temporarily unlock the TTY to locate the process
1715                  * group. This code would be lot nicer if we would ever
1716                  * decompose proctree_lock.
1717                  */
1718                 tty_unlock(tp);
1719                 sx_slock(&proctree_lock);
1720                 pg = pgfind(*(int *)data);
1721                 if (pg != NULL)
1722                         PGRP_UNLOCK(pg);
1723                 if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
1724                         sx_sunlock(&proctree_lock);
1725                         tty_lock(tp);
1726                         return (EPERM);
1727                 }
1728                 tty_lock(tp);
1729
1730                 /*
1731                  * Determine if this TTY is the controlling TTY after
1732                  * relocking the TTY.
1733                  */
1734                 if (!tty_is_ctty(tp, td->td_proc)) {
1735                         sx_sunlock(&proctree_lock);
1736                         return (ENOTTY);
1737                 }
1738                 tp->t_pgrp = pg;
1739                 sx_sunlock(&proctree_lock);
1740
1741                 /* Wake up the background process groups. */
1742                 cv_broadcast(&tp->t_bgwait);
1743                 return (0);
1744         }
1745         case TIOCFLUSH: {
1746                 int flags = *(int *)data;
1747
1748                 if (flags == 0)
1749                         flags = (FREAD|FWRITE);
1750                 else
1751                         flags &= (FREAD|FWRITE);
1752                 tty_flush(tp, flags);
1753                 return (0);
1754         }
1755         case TIOCDRAIN:
1756                 /* Drain TTY output. */
1757                 return tty_drain(tp, 0);
1758         case TIOCCONS:
1759                 /* Set terminal as console TTY. */
1760                 if (*(int *)data) {
1761                         error = priv_check(td, PRIV_TTY_CONSOLE);
1762                         if (error)
1763                                 return (error);
1764
1765                         /*
1766                          * XXX: constty should really need to be locked!
1767                          * XXX: allow disconnected constty's to be stolen!
1768                          */
1769
1770                         if (constty == tp)
1771                                 return (0);
1772                         if (constty != NULL)
1773                                 return (EBUSY);
1774
1775                         tty_unlock(tp);
1776                         constty_set(tp);
1777                         tty_lock(tp);
1778                 } else if (constty == tp) {
1779                         constty_clear();
1780                 }
1781                 return (0);
1782         case TIOCGWINSZ:
1783                 /* Obtain window size. */
1784                 *(struct winsize*)data = tp->t_winsize;
1785                 return (0);
1786         case TIOCSWINSZ:
1787                 /* Set window size. */
1788                 tty_set_winsize(tp, data);
1789                 return (0);
1790         case TIOCEXCL:
1791                 tp->t_flags |= TF_EXCLUDE;
1792                 return (0);
1793         case TIOCNXCL:
1794                 tp->t_flags &= ~TF_EXCLUDE;
1795                 return (0);
1796         case TIOCSTOP:
1797                 tp->t_flags |= TF_STOPPED;
1798                 ttydevsw_pktnotify(tp, TIOCPKT_STOP);
1799                 return (0);
1800         case TIOCSTART:
1801                 tp->t_flags &= ~TF_STOPPED;
1802                 ttydevsw_outwakeup(tp);
1803                 ttydevsw_pktnotify(tp, TIOCPKT_START);
1804                 return (0);
1805         case TIOCSTAT:
1806                 tty_info(tp);
1807                 return (0);
1808         case TIOCSTI:
1809                 if ((fflag & FREAD) == 0 && priv_check(td, PRIV_TTY_STI))
1810                         return (EPERM);
1811                 if (!tty_is_ctty(tp, td->td_proc) &&
1812                     priv_check(td, PRIV_TTY_STI))
1813                         return (EACCES);
1814                 ttydisc_rint(tp, *(char *)data, 0);
1815                 ttydisc_rint_done(tp);
1816                 return (0);
1817         }
1818
1819 #ifdef COMPAT_43TTY
1820         return tty_ioctl_compat(tp, cmd, data, fflag, td);
1821 #else /* !COMPAT_43TTY */
1822         return (ENOIOCTL);
1823 #endif /* COMPAT_43TTY */
1824 }
1825
1826 int
1827 tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag, struct thread *td)
1828 {
1829         int error;
1830
1831         tty_lock_assert(tp, MA_OWNED);
1832
1833         if (tty_gone(tp))
1834                 return (ENXIO);
1835
1836         error = ttydevsw_ioctl(tp, cmd, data, td);
1837         if (error == ENOIOCTL)
1838                 error = tty_generic_ioctl(tp, cmd, data, fflag, td);
1839
1840         return (error);
1841 }
1842
1843 dev_t
1844 tty_udev(struct tty *tp)
1845 {
1846
1847         if (tp->t_dev)
1848                 return (dev2udev(tp->t_dev));
1849         else
1850                 return (NODEV);
1851 }
1852
1853 int
1854 tty_checkoutq(struct tty *tp)
1855 {
1856
1857         /* 256 bytes should be enough to print a log message. */
1858         return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
1859 }
1860
1861 void
1862 tty_hiwat_in_block(struct tty *tp)
1863 {
1864
1865         if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
1866             tp->t_termios.c_iflag & IXOFF &&
1867             tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
1868                 /*
1869                  * Input flow control. Only enter the high watermark when we
1870                  * can successfully store the VSTOP character.
1871                  */
1872                 if (ttyoutq_write_nofrag(&tp->t_outq,
1873                     &tp->t_termios.c_cc[VSTOP], 1) == 0)
1874                         tp->t_flags |= TF_HIWAT_IN;
1875         } else {
1876                 /* No input flow control. */
1877                 tp->t_flags |= TF_HIWAT_IN;
1878         }
1879 }
1880
1881 void
1882 tty_hiwat_in_unblock(struct tty *tp)
1883 {
1884
1885         if (tp->t_flags & TF_HIWAT_IN &&
1886             tp->t_termios.c_iflag & IXOFF &&
1887             tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
1888                 /*
1889                  * Input flow control. Only leave the high watermark when we
1890                  * can successfully store the VSTART character.
1891                  */
1892                 if (ttyoutq_write_nofrag(&tp->t_outq,
1893                     &tp->t_termios.c_cc[VSTART], 1) == 0)
1894                         tp->t_flags &= ~TF_HIWAT_IN;
1895         } else {
1896                 /* No input flow control. */
1897                 tp->t_flags &= ~TF_HIWAT_IN;
1898         }
1899
1900         if (!tty_gone(tp))
1901                 ttydevsw_inwakeup(tp);
1902 }
1903
1904 /*
1905  * TTY hooks interface.
1906  */
1907
1908 static int
1909 ttyhook_defrint(struct tty *tp, char c, int flags)
1910 {
1911
1912         if (ttyhook_rint_bypass(tp, &c, 1) != 1)
1913                 return (-1);
1914
1915         return (0);
1916 }
1917
1918 int
1919 ttyhook_register(struct tty **rtp, struct proc *p, int fd, struct ttyhook *th,
1920     void *softc)
1921 {
1922         struct tty *tp;
1923         struct file *fp;
1924         struct cdev *dev;
1925         struct cdevsw *cdp;
1926         struct filedesc *fdp;
1927         cap_rights_t rights;
1928         int error, ref;
1929
1930         /* Validate the file descriptor. */
1931         fdp = p->p_fd;
1932         error = fget_unlocked(fdp, fd, cap_rights_init(&rights, CAP_TTYHOOK),
1933             &fp, NULL);
1934         if (error != 0)
1935                 return (error);
1936         if (fp->f_ops == &badfileops) {
1937                 error = EBADF;
1938                 goto done1;
1939         }
1940
1941         /*
1942          * Make sure the vnode is bound to a character device.
1943          * Unlocked check for the vnode type is ok there, because we
1944          * only shall prevent calling devvn_refthread on the file that
1945          * never has been opened over a character device.
1946          */
1947         if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
1948                 error = EINVAL;
1949                 goto done1;
1950         }
1951
1952         /* Make sure it is a TTY. */
1953         cdp = devvn_refthread(fp->f_vnode, &dev, &ref);
1954         if (cdp == NULL) {
1955                 error = ENXIO;
1956                 goto done1;
1957         }
1958         if (dev != fp->f_data) {
1959                 error = ENXIO;
1960                 goto done2;
1961         }
1962         if (cdp != &ttydev_cdevsw) {
1963                 error = ENOTTY;
1964                 goto done2;
1965         }
1966         tp = dev->si_drv1;
1967
1968         /* Try to attach the hook to the TTY. */
1969         error = EBUSY;
1970         tty_lock(tp);
1971         MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
1972         if (tp->t_flags & TF_HOOK)
1973                 goto done3;
1974
1975         tp->t_flags |= TF_HOOK;
1976         tp->t_hook = th;
1977         tp->t_hooksoftc = softc;
1978         *rtp = tp;
1979         error = 0;
1980
1981         /* Maybe we can switch into bypass mode now. */
1982         ttydisc_optimize(tp);
1983
1984         /* Silently convert rint() calls to rint_bypass() when possible. */
1985         if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
1986                 th->th_rint = ttyhook_defrint;
1987
1988 done3:  tty_unlock(tp);
1989 done2:  dev_relthread(dev, ref);
1990 done1:  fdrop(fp, curthread);
1991         return (error);
1992 }
1993
1994 void
1995 ttyhook_unregister(struct tty *tp)
1996 {
1997
1998         tty_lock_assert(tp, MA_OWNED);
1999         MPASS(tp->t_flags & TF_HOOK);
2000
2001         /* Disconnect the hook. */
2002         tp->t_flags &= ~TF_HOOK;
2003         tp->t_hook = NULL;
2004
2005         /* Maybe we need to leave bypass mode. */
2006         ttydisc_optimize(tp);
2007
2008         /* Maybe deallocate the TTY as well. */
2009         tty_rel_free(tp);
2010 }
2011
2012 /*
2013  * /dev/console handling.
2014  */
2015
2016 static int
2017 ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
2018 {
2019         struct tty *tp;
2020
2021         /* System has no console device. */
2022         if (dev_console_filename == NULL)
2023                 return (ENXIO);
2024
2025         /* Look up corresponding TTY by device name. */
2026         sx_slock(&tty_list_sx);
2027         TAILQ_FOREACH(tp, &tty_list, t_list) {
2028                 if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
2029                         dev_console->si_drv1 = tp;
2030                         break;
2031                 }
2032         }
2033         sx_sunlock(&tty_list_sx);
2034
2035         /* System console has no TTY associated. */
2036         if (dev_console->si_drv1 == NULL)
2037                 return (ENXIO);
2038
2039         return (ttydev_open(dev, oflags, devtype, td));
2040 }
2041
2042 static int
2043 ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
2044 {
2045
2046         log_console(uio);
2047
2048         return (ttydev_write(dev, uio, ioflag));
2049 }
2050
2051 /*
2052  * /dev/console is a little different than normal TTY's.  When opened,
2053  * it determines which TTY to use.  When data gets written to it, it
2054  * will be logged in the kernel message buffer.
2055  */
2056 static struct cdevsw ttyconsdev_cdevsw = {
2057         .d_version      = D_VERSION,
2058         .d_open         = ttyconsdev_open,
2059         .d_close        = ttydev_close,
2060         .d_read         = ttydev_read,
2061         .d_write        = ttyconsdev_write,
2062         .d_ioctl        = ttydev_ioctl,
2063         .d_kqfilter     = ttydev_kqfilter,
2064         .d_poll         = ttydev_poll,
2065         .d_mmap         = ttydev_mmap,
2066         .d_name         = "ttyconsdev",
2067         .d_flags        = D_TTY,
2068 };
2069
2070 static void
2071 ttyconsdev_init(void *unused __unused)
2072 {
2073
2074         dev_console = make_dev_credf(MAKEDEV_ETERNAL, &ttyconsdev_cdevsw, 0,
2075             NULL, UID_ROOT, GID_WHEEL, 0600, "console");
2076 }
2077
2078 SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
2079
2080 void
2081 ttyconsdev_select(const char *name)
2082 {
2083
2084         dev_console_filename = name;
2085 }
2086
2087 /*
2088  * Debugging routines.
2089  */
2090
2091 #include "opt_ddb.h"
2092 #ifdef DDB
2093 #include <ddb/ddb.h>
2094 #include <ddb/db_sym.h>
2095
2096 static const struct {
2097         int flag;
2098         char val;
2099 } ttystates[] = {
2100 #if 0
2101         { TF_NOPREFIX,          'N' },
2102 #endif
2103         { TF_INITLOCK,          'I' },
2104         { TF_CALLOUT,           'C' },
2105
2106         /* Keep these together -> 'Oi' and 'Oo'. */
2107         { TF_OPENED,            'O' },
2108         { TF_OPENED_IN,         'i' },
2109         { TF_OPENED_OUT,        'o' },
2110         { TF_OPENED_CONS,       'c' },
2111
2112         { TF_GONE,              'G' },
2113         { TF_OPENCLOSE,         'B' },
2114         { TF_ASYNC,             'Y' },
2115         { TF_LITERAL,           'L' },
2116
2117         /* Keep these together -> 'Hi' and 'Ho'. */
2118         { TF_HIWAT,             'H' },
2119         { TF_HIWAT_IN,          'i' },
2120         { TF_HIWAT_OUT,         'o' },
2121
2122         { TF_STOPPED,           'S' },
2123         { TF_EXCLUDE,           'X' },
2124         { TF_BYPASS,            'l' },
2125         { TF_ZOMBIE,            'Z' },
2126         { TF_HOOK,              's' },
2127
2128         /* Keep these together -> 'bi' and 'bo'. */
2129         { TF_BUSY,              'b' },
2130         { TF_BUSY_IN,           'i' },
2131         { TF_BUSY_OUT,          'o' },
2132
2133         { 0,                    '\0'},
2134 };
2135
2136 #define TTY_FLAG_BITS \
2137         "\20\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN" \
2138         "\5OPENED_OUT\6OPENED_CONS\7GONE\10OPENCLOSE" \
2139         "\11ASYNC\12LITERAL\13HIWAT_IN\14HIWAT_OUT" \
2140         "\15STOPPED\16EXCLUDE\17BYPASS\20ZOMBIE" \
2141         "\21HOOK\22BUSY_IN\23BUSY_OUT"
2142
2143 #define DB_PRINTSYM(name, addr) \
2144         db_printf("%s  " #name ": ", sep); \
2145         db_printsym((db_addr_t) addr, DB_STGY_ANY); \
2146         db_printf("\n");
2147
2148 static void
2149 _db_show_devsw(const char *sep, const struct ttydevsw *tsw)
2150 {
2151
2152         db_printf("%sdevsw: ", sep);
2153         db_printsym((db_addr_t)tsw, DB_STGY_ANY);
2154         db_printf(" (%p)\n", tsw);
2155         DB_PRINTSYM(open, tsw->tsw_open);
2156         DB_PRINTSYM(close, tsw->tsw_close);
2157         DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
2158         DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
2159         DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
2160         DB_PRINTSYM(param, tsw->tsw_param);
2161         DB_PRINTSYM(modem, tsw->tsw_modem);
2162         DB_PRINTSYM(mmap, tsw->tsw_mmap);
2163         DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
2164         DB_PRINTSYM(free, tsw->tsw_free);
2165 }
2166
2167 static void
2168 _db_show_hooks(const char *sep, const struct ttyhook *th)
2169 {
2170
2171         db_printf("%shook: ", sep);
2172         db_printsym((db_addr_t)th, DB_STGY_ANY);
2173         db_printf(" (%p)\n", th);
2174         if (th == NULL)
2175                 return;
2176         DB_PRINTSYM(rint, th->th_rint);
2177         DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
2178         DB_PRINTSYM(rint_done, th->th_rint_done);
2179         DB_PRINTSYM(rint_poll, th->th_rint_poll);
2180         DB_PRINTSYM(getc_inject, th->th_getc_inject);
2181         DB_PRINTSYM(getc_capture, th->th_getc_capture);
2182         DB_PRINTSYM(getc_poll, th->th_getc_poll);
2183         DB_PRINTSYM(close, th->th_close);
2184 }
2185
2186 static void
2187 _db_show_termios(const char *name, const struct termios *t)
2188 {
2189
2190         db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
2191             "lflag 0x%x ispeed %u ospeed %u\n", name,
2192             t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
2193             t->c_ispeed, t->c_ospeed);
2194 }
2195
2196 /* DDB command to show TTY statistics. */
2197 DB_SHOW_COMMAND(tty, db_show_tty)
2198 {
2199         struct tty *tp;
2200
2201         if (!have_addr) {
2202                 db_printf("usage: show tty <addr>\n");
2203                 return;
2204         }
2205         tp = (struct tty *)addr;
2206
2207         db_printf("%p: %s\n", tp, tty_devname(tp));
2208         db_printf("\tmtx: %p\n", tp->t_mtx);
2209         db_printf("\tflags: 0x%b\n", tp->t_flags, TTY_FLAG_BITS);
2210         db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
2211
2212         /* Buffering mechanisms. */
2213         db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
2214             "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
2215             tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
2216             tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
2217         db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
2218             &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
2219             tp->t_outq.to_nblocks, tp->t_outq.to_quota);
2220         db_printf("\tinlow: %zu\n", tp->t_inlow);
2221         db_printf("\toutlow: %zu\n", tp->t_outlow);
2222         _db_show_termios("\ttermios", &tp->t_termios);
2223         db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
2224             tp->t_winsize.ws_row, tp->t_winsize.ws_col,
2225             tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
2226         db_printf("\tcolumn: %u\n", tp->t_column);
2227         db_printf("\twritepos: %u\n", tp->t_writepos);
2228         db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
2229
2230         /* Init/lock-state devices. */
2231         _db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
2232         _db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
2233         _db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
2234         _db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
2235
2236         /* Hooks */
2237         _db_show_devsw("\t", tp->t_devsw);
2238         _db_show_hooks("\t", tp->t_hook);
2239
2240         /* Process info. */
2241         db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
2242             tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
2243             tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
2244         db_printf("\tsession: %p", tp->t_session);
2245         if (tp->t_session != NULL)
2246             db_printf(" count %u leader %p tty %p sid %d login %s",
2247                 tp->t_session->s_count, tp->t_session->s_leader,
2248                 tp->t_session->s_ttyp, tp->t_session->s_sid,
2249                 tp->t_session->s_login);
2250         db_printf("\n");
2251         db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
2252         db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
2253         db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
2254         db_printf("\tdev: %p\n", tp->t_dev);
2255 }
2256
2257 /* DDB command to list TTYs. */
2258 DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
2259 {
2260         struct tty *tp;
2261         size_t isiz, osiz;
2262         int i, j;
2263
2264         /* Make the output look like `pstat -t'. */
2265         db_printf("PTR        ");
2266 #if defined(__LP64__)
2267         db_printf("        ");
2268 #endif
2269         db_printf("      LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   "
2270             "COL  SESS  PGID STATE\n");
2271
2272         TAILQ_FOREACH(tp, &tty_list, t_list) {
2273                 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
2274                 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
2275
2276                 db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d "
2277                     "%5d ", tp, tty_devname(tp), isiz,
2278                     tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
2279                     tp->t_inq.ti_end - tp->t_inq.ti_linestart,
2280                     isiz - tp->t_inlow, osiz,
2281                     tp->t_outq.to_end - tp->t_outq.to_begin,
2282                     osiz - tp->t_outlow, MIN(tp->t_column, 99999),
2283                     tp->t_session ? tp->t_session->s_sid : 0,
2284                     tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
2285
2286                 /* Flag bits. */
2287                 for (i = j = 0; ttystates[i].flag; i++)
2288                         if (tp->t_flags & ttystates[i].flag) {
2289                                 db_printf("%c", ttystates[i].val);
2290                                 j++;
2291                         }
2292                 if (j == 0)
2293                         db_printf("-");
2294                 db_printf("\n");
2295         }
2296 }
2297 #endif /* DDB */