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, revokecnt;
 130
 131         if (ttyhook_hashook(tp, getc_inject))
 132                 /* buffer is inaccessible */
 133                 return (0);
 134
 135         while (ttyoutq_bytesused(&tp->t_outq) > 0) {
 136                 ttydevsw_outwakeup(tp);
 137                 /* Could be handled synchronously. */
 138                 bytesused = ttyoutq_bytesused(&tp->t_outq);
 139                 if (bytesused == 0)
 140                         return (0);
 141
 142                 /* Wait for data to be drained. */
 143                 if (leaving) {
 144                         revokecnt = tp->t_revokecnt;
 145                         error = tty_timedwait(tp, &tp->t_outwait, hz);
 146                         switch (error) {
 147                         case ERESTART:
 148                                 if (revokecnt != tp->t_revokecnt)
 149                                         error = 0;
 150                                 break;
 151                         case EWOULDBLOCK:
 152                                 if (ttyoutq_bytesused(&tp->t_outq) < bytesused)
 153                                         error = 0;
 154                                 break;
 155                         }
 156                 } else
 157                         error = tty_wait(tp, &tp->t_outwait);
 158
 159                 if (error)
 160                         return (error);
 161         }
 162
 163         return (0);
 164 }
 165
 166 /*
 167  * Though ttydev_enter() and ttydev_leave() seem to be related, they
 168  * don't have to be used together. ttydev_enter() is used by the cdev
 169  * operations to prevent an actual operation from being processed when
 170  * the TTY has been abandoned. ttydev_leave() is used by ttydev_open()
 171  * and ttydev_close() to determine whether per-TTY data should be
 172  * deallocated.
 173  */
 174
 175 static __inline int
 176 ttydev_enter(struct tty *tp)
 177 {
 178         tty_lock(tp);
 179
 180         if (tty_gone(tp) || !tty_opened(tp)) {
 181                 /* Device is already gone. */
 182                 tty_unlock(tp);
 183                 return (ENXIO);
 184         }
 185
 186         return (0);
 187 }
 188
 189 static void
 190 ttydev_leave(struct tty *tp)
 191 {
 192         tty_lock_assert(tp, MA_OWNED);
 193
 194         if (tty_opened(tp) || tp->t_flags & TF_OPENCLOSE) {
 195                 /* Device is still opened somewhere. */
 196                 tty_unlock(tp);
 197                 return;
 198         }
 199
 200         tp->t_flags |= TF_OPENCLOSE;
 201
 202         /* Stop asynchronous I/O. */
 203         funsetown(&tp->t_sigio);
 204
 205         /* Remove console TTY. */
 206         if (constty == tp)
 207                 constty_clear();
 208
 209         /* Drain any output. */
 210         MPASS((tp->t_flags & TF_STOPPED) == 0);
 211         if (!tty_gone(tp))
 212                 tty_drain(tp, 1);
 213
 214         ttydisc_close(tp);
 215
 216         /* Destroy associated buffers already. */
 217         ttyinq_free(&tp->t_inq);
 218         tp->t_inlow = 0;
 219         ttyoutq_free(&tp->t_outq);
 220         tp->t_outlow = 0;
 221
 222         knlist_clear(&tp->t_inpoll.si_note, 1);
 223         knlist_clear(&tp->t_outpoll.si_note, 1);
 224
 225         if (!tty_gone(tp))
 226                 ttydevsw_close(tp);
 227
 228         tp->t_flags &= ~TF_OPENCLOSE;
 229         cv_broadcast(&tp->t_dcdwait);
 230         tty_rel_free(tp);
 231 }
 232
 233 /*
 234  * Operations that are exposed through the character device in /dev.
 235  */
 236 static int
 237 ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 238 {
 239         struct tty *tp;
 240         int error = 0;
 241
 242         while ((tp = dev->si_drv1) == NULL) {
 243                 error = tsleep(&dev->si_drv1, PCATCH, "ttdrv1", 1);
 244                 if (error != EWOULDBLOCK)
 245                         return (error);
 246         }
 247
 248         tty_lock(tp);
 249         if (tty_gone(tp)) {
 250                 /* Device is already gone. */
 251                 tty_unlock(tp);
 252                 return (ENXIO);
 253         }
 254
 255         /*
 256          * Block when other processes are currently opening or closing
 257          * the TTY.
 258          */
 259         while (tp->t_flags & TF_OPENCLOSE) {
 260                 error = tty_wait(tp, &tp->t_dcdwait);
 261                 if (error != 0) {
 262                         tty_unlock(tp);
 263                         return (error);
 264                 }
 265         }
 266         tp->t_flags |= TF_OPENCLOSE;
 267
 268         /*
 269          * Make sure the "tty" and "cua" device cannot be opened at the
 270          * same time.
 271          */
 272         if (TTY_CALLOUT(tp, dev)) {
 273                 if (tp->t_flags & TF_OPENED_IN) {
 274                         error = EBUSY;
 275                         goto done;
 276                 }
 277         } else {
 278                 if (tp->t_flags & TF_OPENED_OUT) {
 279                         error = EBUSY;
 280                         goto done;
 281                 }
 282         }
 283
 284         if (tp->t_flags & TF_EXCLUDE && priv_check(td, PRIV_TTY_EXCLUSIVE)) {
 285                 error = EBUSY;
 286                 goto done;
 287         }
 288
 289         if (!tty_opened(tp)) {
 290                 /* Set proper termios flags. */
 291                 if (TTY_CALLOUT(tp, dev))
 292                         tp->t_termios = tp->t_termios_init_out;
 293                 else
 294                         tp->t_termios = tp->t_termios_init_in;
 295                 ttydevsw_param(tp, &tp->t_termios);
 296                 /* Prevent modem control on callout devices and /dev/console. */
 297                 if (TTY_CALLOUT(tp, dev) || dev == dev_console)
 298                         tp->t_termios.c_cflag |= CLOCAL;
 299
 300                 ttydevsw_modem(tp, SER_DTR|SER_RTS, 0);
 301
 302                 error = ttydevsw_open(tp);
 303                 if (error != 0)
 304                         goto done;
 305
 306                 ttydisc_open(tp);
 307                 tty_watermarks(tp); /* XXXGL: drops lock */
 308         }
 309
 310         /* Wait for Carrier Detect. */
 311         if ((oflags & O_NONBLOCK) == 0 &&
 312             (tp->t_termios.c_cflag & CLOCAL) == 0) {
 313                 while ((ttydevsw_modem(tp, 0, 0) & SER_DCD) == 0) {
 314                         error = tty_wait(tp, &tp->t_dcdwait);
 315                         if (error != 0)
 316                                 goto done;
 317                 }
 318         }
 319
 320         if (dev == dev_console)
 321                 tp->t_flags |= TF_OPENED_CONS;
 322         else if (TTY_CALLOUT(tp, dev))
 323                 tp->t_flags |= TF_OPENED_OUT;
 324         else
 325                 tp->t_flags |= TF_OPENED_IN;
 326
 327 done:   tp->t_flags &= ~TF_OPENCLOSE;
 328         cv_broadcast(&tp->t_dcdwait);
 329         ttydev_leave(tp);
 330
 331         return (error);
 332 }
 333
 334 static int
 335 ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
 336 {
 337         struct tty *tp = dev->si_drv1;
 338
 339         tty_lock(tp);
 340
 341         /*
 342          * Don't actually close the device if it is being used as the
 343          * console.
 344          */
 345         MPASS((tp->t_flags & TF_OPENED) != TF_OPENED);
 346         if (dev == dev_console)
 347                 tp->t_flags &= ~TF_OPENED_CONS;
 348         else
 349                 tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);
 350
 351         if (tp->t_flags & TF_OPENED) {
 352                 tty_unlock(tp);
 353                 return (0);
 354         }
 355
 356         /*
 357          * This can only be called once. The callin and the callout
 358          * devices cannot be opened at the same time.
 359          */
 360         tp->t_flags &= ~(TF_EXCLUDE|TF_STOPPED);
 361
 362         /* Properly wake up threads that are stuck - revoke(). */
 363         tp->t_revokecnt++;
 364         tty_wakeup(tp, FREAD|FWRITE);
 365         cv_broadcast(&tp->t_bgwait);
 366         cv_broadcast(&tp->t_dcdwait);
 367
 368         ttydev_leave(tp);
 369
 370         return (0);
 371 }
 372
 373 static __inline int
 374 tty_is_ctty(struct tty *tp, struct proc *p)
 375 {
 376         tty_lock_assert(tp, MA_OWNED);
 377
 378         return (p->p_session == tp->t_session && p->p_flag & P_CONTROLT);
 379 }
 380
 381 int
 382 tty_wait_background(struct tty *tp, struct thread *td, int sig)
 383 {
 384         struct proc *p = td->td_proc;
 385         struct pgrp *pg;
 386         ksiginfo_t ksi;
 387         int error;
 388
 389         MPASS(sig == SIGTTIN || sig == SIGTTOU);
 390         tty_lock_assert(tp, MA_OWNED);
 391
 392         for (;;) {
 393                 PROC_LOCK(p);
 394                 /*
 395                  * The process should only sleep, when:
 396                  * - This terminal is the controling terminal
 397                  * - Its process group is not the foreground process
 398                  *   group
 399                  * - The parent process isn't waiting for the child to
 400                  *   exit
 401                  * - the signal to send to the process isn't masked
 402                  */
 403                 if (!tty_is_ctty(tp, p) || p->p_pgrp == tp->t_pgrp) {
 404                         /* Allow the action to happen. */
 405                         PROC_UNLOCK(p);
 406                         return (0);
 407                 }
 408
 409                 if (SIGISMEMBER(p->p_sigacts->ps_sigignore, sig) ||
 410                     SIGISMEMBER(td->td_sigmask, sig)) {
 411                         /* Only allow them in write()/ioctl(). */
 412                         PROC_UNLOCK(p);
 413                         return (sig == SIGTTOU ? 0 : EIO);
 414                 }
 415
 416                 pg = p->p_pgrp;
 417                 if (p->p_flag & P_PPWAIT || pg->pg_jobc == 0) {
 418                         /* Don't allow the action to happen. */
 419                         PROC_UNLOCK(p);
 420                         return (EIO);
 421                 }
 422                 PROC_UNLOCK(p);
 423
 424                 /*
 425                  * Send the signal and sleep until we're the new
 426                  * foreground process group.
 427                  */
 428                 if (sig != 0) {
 429                         ksiginfo_init(&ksi);
 430                         ksi.ksi_code = SI_KERNEL;
 431                         ksi.ksi_signo = sig;
 432                         sig = 0;
 433                 }
 434                 PGRP_LOCK(pg);
 435                 pgsignal(pg, ksi.ksi_signo, 1, &ksi);
 436                 PGRP_UNLOCK(pg);
 437
 438                 error = tty_wait(tp, &tp->t_bgwait);
 439                 if (error)
 440                         return (error);
 441         }
 442 }
 443
 444 static int
 445 ttydev_read(struct cdev *dev, struct uio *uio, int ioflag)
 446 {
 447         struct tty *tp = dev->si_drv1;
 448         int error;
 449
 450         error = ttydev_enter(tp);
 451         if (error)
 452                 goto done;
 453         error = ttydisc_read(tp, uio, ioflag);
 454         tty_unlock(tp);
 455
 456         /*
 457          * The read() call should not throw an error when the device is
 458          * being destroyed. Silently convert it to an EOF.
 459          */
 460 done:   if (error == ENXIO)
 461                 error = 0;
 462         return (error);
 463 }
 464
 465 static int
 466 ttydev_write(struct cdev *dev, struct uio *uio, int ioflag)
 467 {
 468         struct tty *tp = dev->si_drv1;
 469         int error;
 470
 471         error = ttydev_enter(tp);
 472         if (error)
 473                 return (error);
 474
 475         if (tp->t_termios.c_lflag & TOSTOP) {
 476                 error = tty_wait_background(tp, curthread, SIGTTOU);
 477                 if (error)
 478                         goto done;
 479         }
 480
 481         if (ioflag & IO_NDELAY && tp->t_flags & TF_BUSY_OUT) {
 482                 /* Allow non-blocking writes to bypass serialization. */
 483                 error = ttydisc_write(tp, uio, ioflag);
 484         } else {
 485                 /* Serialize write() calls. */
 486                 while (tp->t_flags & TF_BUSY_OUT) {
 487                         error = tty_wait(tp, &tp->t_outserwait);
 488                         if (error)
 489                                 goto done;
 490                 }
 491
 492                 tp->t_flags |= TF_BUSY_OUT;
 493                 error = ttydisc_write(tp, uio, ioflag);
 494                 tp->t_flags &= ~TF_BUSY_OUT;
 495                 cv_signal(&tp->t_outserwait);
 496         }
 497
 498 done:   tty_unlock(tp);
 499         return (error);
 500 }
 501
 502 static int
 503 ttydev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 504     struct thread *td)
 505 {
 506         struct tty *tp = dev->si_drv1;
 507         int error;
 508
 509         error = ttydev_enter(tp);
 510         if (error)
 511                 return (error);
 512
 513         switch (cmd) {
 514         case TIOCCBRK:
 515         case TIOCCONS:
 516         case TIOCDRAIN:
 517         case TIOCEXCL:
 518         case TIOCFLUSH:
 519         case TIOCNXCL:
 520         case TIOCSBRK:
 521         case TIOCSCTTY:
 522         case TIOCSETA:
 523         case TIOCSETAF:
 524         case TIOCSETAW:
 525         case TIOCSPGRP:
 526         case TIOCSTART:
 527         case TIOCSTAT:
 528         case TIOCSTI:
 529         case TIOCSTOP:
 530         case TIOCSWINSZ:
 531 #if 0
 532         case TIOCSDRAINWAIT:
 533         case TIOCSETD:
 534 #endif
 535 #ifdef COMPAT_43TTY
 536         case  TIOCLBIC:
 537         case  TIOCLBIS:
 538         case  TIOCLSET:
 539         case  TIOCSETC:
 540         case OTIOCSETD:
 541         case  TIOCSETN:
 542         case  TIOCSETP:
 543         case  TIOCSLTC:
 544 #endif /* COMPAT_43TTY */
 545                 /*
 546                  * If the ioctl() causes the TTY to be modified, let it
 547                  * wait in the background.
 548                  */
 549                 error = tty_wait_background(tp, curthread, SIGTTOU);
 550                 if (error)
 551                         goto done;
 552         }
 553
 554         if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
 555                 struct termios *old = &tp->t_termios;
 556                 struct termios *new = (struct termios *)data;
 557                 struct termios *lock = TTY_CALLOUT(tp, dev) ?
 558                     &tp->t_termios_lock_out : &tp->t_termios_lock_in;
 559                 int cc;
 560
 561                 /*
 562                  * Lock state devices.  Just overwrite the values of the
 563                  * commands that are currently in use.
 564                  */
 565                 new->c_iflag = (old->c_iflag & lock->c_iflag) |
 566                     (new->c_iflag & ~lock->c_iflag);
 567                 new->c_oflag = (old->c_oflag & lock->c_oflag) |
 568                     (new->c_oflag & ~lock->c_oflag);
 569                 new->c_cflag = (old->c_cflag & lock->c_cflag) |
 570                     (new->c_cflag & ~lock->c_cflag);
 571                 new->c_lflag = (old->c_lflag & lock->c_lflag) |
 572                     (new->c_lflag & ~lock->c_lflag);
 573                 for (cc = 0; cc < NCCS; ++cc)
 574                         if (lock->c_cc[cc])
 575                                 new->c_cc[cc] = old->c_cc[cc];
 576                 if (lock->c_ispeed)
 577                         new->c_ispeed = old->c_ispeed;
 578                 if (lock->c_ospeed)
 579                         new->c_ospeed = old->c_ospeed;
 580         }
 581
 582         error = tty_ioctl(tp, cmd, data, fflag, td);
 583 done:   tty_unlock(tp);
 584
 585         return (error);
 586 }
 587
 588 static int
 589 ttydev_poll(struct cdev *dev, int events, struct thread *td)
 590 {
 591         struct tty *tp = dev->si_drv1;
 592         int error, revents = 0;
 593
 594         error = ttydev_enter(tp);
 595         if (error)
 596                 return ((events & (POLLIN|POLLRDNORM)) | POLLHUP);
 597
 598         if (events & (POLLIN|POLLRDNORM)) {
 599                 /* See if we can read something. */
 600                 if (ttydisc_read_poll(tp) > 0)
 601                         revents |= events & (POLLIN|POLLRDNORM);
 602         }
 603
 604         if (tp->t_flags & TF_ZOMBIE) {
 605                 /* Hangup flag on zombie state. */
 606                 revents |= POLLHUP;
 607         } else if (events & (POLLOUT|POLLWRNORM)) {
 608                 /* See if we can write something. */
 609                 if (ttydisc_write_poll(tp) > 0)
 610                         revents |= events & (POLLOUT|POLLWRNORM);
 611         }
 612
 613         if (revents == 0) {
 614                 if (events & (POLLIN|POLLRDNORM))
 615                         selrecord(td, &tp->t_inpoll);
 616                 if (events & (POLLOUT|POLLWRNORM))
 617                         selrecord(td, &tp->t_outpoll);
 618         }
 619
 620         tty_unlock(tp);
 621
 622         return (revents);
 623 }
 624
 625 static int
 626 ttydev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
 627     int nprot, vm_memattr_t *memattr)
 628 {
 629         struct tty *tp = dev->si_drv1;
 630         int error;
 631
 632         /* Handle mmap() through the driver. */
 633
 634         error = ttydev_enter(tp);
 635         if (error)
 636                 return (-1);
 637         error = ttydevsw_mmap(tp, offset, paddr, nprot, memattr);
 638         tty_unlock(tp);
 639
 640         return (error);
 641 }
 642
 643 /*
 644  * kqueue support.
 645  */
 646
 647 static void
 648 tty_kqops_read_detach(struct knote *kn)
 649 {
 650         struct tty *tp = kn->kn_hook;
 651
 652         knlist_remove(&tp->t_inpoll.si_note, kn, 0);
 653 }
 654
 655 static int
 656 tty_kqops_read_event(struct knote *kn, long hint)
 657 {
 658         struct tty *tp = kn->kn_hook;
 659
 660         tty_lock_assert(tp, MA_OWNED);
 661
 662         if (tty_gone(tp) || tp->t_flags & TF_ZOMBIE) {
 663                 kn->kn_flags |= EV_EOF;
 664                 return (1);
 665         } else {
 666                 kn->kn_data = ttydisc_read_poll(tp);
 667                 return (kn->kn_data > 0);
 668         }
 669 }
 670
 671 static void
 672 tty_kqops_write_detach(struct knote *kn)
 673 {
 674         struct tty *tp = kn->kn_hook;
 675
 676         knlist_remove(&tp->t_outpoll.si_note, kn, 0);
 677 }
 678
 679 static int
 680 tty_kqops_write_event(struct knote *kn, long hint)
 681 {
 682         struct tty *tp = kn->kn_hook;
 683
 684         tty_lock_assert(tp, MA_OWNED);
 685
 686         if (tty_gone(tp)) {
 687                 kn->kn_flags |= EV_EOF;
 688                 return (1);
 689         } else {
 690                 kn->kn_data = ttydisc_write_poll(tp);
 691                 return (kn->kn_data > 0);
 692         }
 693 }
 694
 695 static struct filterops tty_kqops_read = {
 696         .f_isfd = 1,
 697         .f_detach = tty_kqops_read_detach,
 698         .f_event = tty_kqops_read_event,
 699 };
 700 static struct filterops tty_kqops_write = {
 701         .f_isfd = 1,
 702         .f_detach = tty_kqops_write_detach,
 703         .f_event = tty_kqops_write_event,
 704 };
 705
 706 static int
 707 ttydev_kqfilter(struct cdev *dev, struct knote *kn)
 708 {
 709         struct tty *tp = dev->si_drv1;
 710         int error;
 711
 712         error = ttydev_enter(tp);
 713         if (error)
 714                 return (error);
 715
 716         switch (kn->kn_filter) {
 717         case EVFILT_READ:
 718                 kn->kn_hook = tp;
 719                 kn->kn_fop = &tty_kqops_read;
 720                 knlist_add(&tp->t_inpoll.si_note, kn, 1);
 721                 break;
 722         case EVFILT_WRITE:
 723                 kn->kn_hook = tp;
 724                 kn->kn_fop = &tty_kqops_write;
 725                 knlist_add(&tp->t_outpoll.si_note, kn, 1);
 726                 break;
 727         default:
 728                 error = EINVAL;
 729                 break;
 730         }
 731
 732         tty_unlock(tp);
 733         return (error);
 734 }
 735
 736 static struct cdevsw ttydev_cdevsw = {
 737         .d_version      = D_VERSION,
 738         .d_open         = ttydev_open,
 739         .d_close        = ttydev_close,
 740         .d_read         = ttydev_read,
 741         .d_write        = ttydev_write,
 742         .d_ioctl        = ttydev_ioctl,
 743         .d_kqfilter     = ttydev_kqfilter,
 744         .d_poll         = ttydev_poll,
 745         .d_mmap         = ttydev_mmap,
 746         .d_name         = "ttydev",
 747         .d_flags        = D_TTY,
 748 };
 749
 750 /*
 751  * Init/lock-state devices
 752  */
 753
 754 static int
 755 ttyil_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 756 {
 757         struct tty *tp;
 758         int error = 0;
 759
 760         while ((tp = dev->si_drv1) == NULL) {
 761                 error = tsleep(&dev->si_drv1, PCATCH, "ttdrv1", 1);
 762                 if (error != EWOULDBLOCK)
 763                         return (error);
 764         }
 765         tty_lock(tp);
 766         if (tty_gone(tp))
 767                 error = ENODEV;
 768         tty_unlock(tp);
 769
 770         return (error);
 771 }
 772
 773 static int
 774 ttyil_close(struct cdev *dev, int flag, int mode, struct thread *td)
 775 {
 776         return (0);
 777 }
 778
 779 static int
 780 ttyil_rdwr(struct cdev *dev, struct uio *uio, int ioflag)
 781 {
 782         return (ENODEV);
 783 }
 784
 785 static int
 786 ttyil_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
 787     struct thread *td)
 788 {
 789         struct tty *tp = dev->si_drv1;
 790         int error;
 791
 792         tty_lock(tp);
 793         if (tty_gone(tp)) {
 794                 error = ENODEV;
 795                 goto done;
 796         }
 797
 798         error = ttydevsw_cioctl(tp, dev2unit(dev), cmd, data, td);
 799         if (error != ENOIOCTL)
 800                 goto done;
 801         error = 0;
 802
 803         switch (cmd) {
 804         case TIOCGETA:
 805                 /* Obtain terminal flags through tcgetattr(). */
 806                 *(struct termios*)data = *(struct termios*)dev->si_drv2;
 807                 break;
 808         case TIOCSETA:
 809                 /* Set terminal flags through tcsetattr(). */
 810                 error = priv_check(td, PRIV_TTY_SETA);
 811                 if (error)
 812                         break;
 813                 *(struct termios*)dev->si_drv2 = *(struct termios*)data;
 814                 break;
 815         case TIOCGETD:
 816                 *(int *)data = TTYDISC;
 817                 break;
 818         case TIOCGWINSZ:
 819                 bzero(data, sizeof(struct winsize));
 820                 break;
 821         default:
 822                 error = ENOTTY;
 823         }
 824
 825 done:   tty_unlock(tp);
 826         return (error);
 827 }
 828
 829 static struct cdevsw ttyil_cdevsw = {
 830         .d_version      = D_VERSION,
 831         .d_open         = ttyil_open,
 832         .d_close        = ttyil_close,
 833         .d_read         = ttyil_rdwr,
 834         .d_write        = ttyil_rdwr,
 835         .d_ioctl        = ttyil_ioctl,
 836         .d_name         = "ttyil",
 837         .d_flags        = D_TTY,
 838 };
 839
 840 static void
 841 tty_init_termios(struct tty *tp)
 842 {
 843         struct termios *t = &tp->t_termios_init_in;
 844
 845         t->c_cflag = TTYDEF_CFLAG;
 846         t->c_iflag = TTYDEF_IFLAG;
 847         t->c_lflag = TTYDEF_LFLAG;
 848         t->c_oflag = TTYDEF_OFLAG;
 849         t->c_ispeed = TTYDEF_SPEED;
 850         t->c_ospeed = TTYDEF_SPEED;
 851         memcpy(&t->c_cc, ttydefchars, sizeof ttydefchars);
 852
 853         tp->t_termios_init_out = *t;
 854 }
 855
 856 void
 857 tty_init_console(struct tty *tp, speed_t s)
 858 {
 859         struct termios *ti = &tp->t_termios_init_in;
 860         struct termios *to = &tp->t_termios_init_out;
 861
 862         if (s != 0) {
 863                 ti->c_ispeed = ti->c_ospeed = s;
 864                 to->c_ispeed = to->c_ospeed = s;
 865         }
 866
 867         ti->c_cflag |= CLOCAL;
 868         to->c_cflag |= CLOCAL;
 869 }
 870
 871 /*
 872  * Standard device routine implementations, mostly meant for
 873  * pseudo-terminal device drivers. When a driver creates a new terminal
 874  * device class, missing routines are patched.
 875  */
 876
 877 static int
 878 ttydevsw_defopen(struct tty *tp)
 879 {
 880
 881         return (0);
 882 }
 883
 884 static void
 885 ttydevsw_defclose(struct tty *tp)
 886 {
 887 }
 888
 889 static void
 890 ttydevsw_defoutwakeup(struct tty *tp)
 891 {
 892
 893         panic("Terminal device has output, while not implemented");
 894 }
 895
 896 static void
 897 ttydevsw_definwakeup(struct tty *tp)
 898 {
 899 }
 900
 901 static int
 902 ttydevsw_defioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
 903 {
 904
 905         return (ENOIOCTL);
 906 }
 907
 908 static int
 909 ttydevsw_defcioctl(struct tty *tp, int unit, u_long cmd, caddr_t data, struct thread *td)
 910 {
 911
 912         return (ENOIOCTL);
 913 }
 914
 915 static int
 916 ttydevsw_defparam(struct tty *tp, struct termios *t)
 917 {
 918
 919         /*
 920          * Allow the baud rate to be adjusted for pseudo-devices, but at
 921          * least restrict it to 115200 to prevent excessive buffer
 922          * usage.  Also disallow 0, to prevent foot shooting.
 923          */
 924         if (t->c_ispeed < B50)
 925                 t->c_ispeed = B50;
 926         else if (t->c_ispeed > B115200)
 927                 t->c_ispeed = B115200;
 928         if (t->c_ospeed < B50)
 929                 t->c_ospeed = B50;
 930         else if (t->c_ospeed > B115200)
 931                 t->c_ospeed = B115200;
 932         t->c_cflag |= CREAD;
 933
 934         return (0);
 935 }
 936
 937 static int
 938 ttydevsw_defmodem(struct tty *tp, int sigon, int sigoff)
 939 {
 940
 941         /* Simulate a carrier to make the TTY layer happy. */
 942         return (SER_DCD);
 943 }
 944
 945 static int
 946 ttydevsw_defmmap(struct tty *tp, vm_ooffset_t offset, vm_paddr_t *paddr,
 947     int nprot, vm_memattr_t *memattr)
 948 {
 949
 950         return (-1);
 951 }
 952
 953 static void
 954 ttydevsw_defpktnotify(struct tty *tp, char event)
 955 {
 956 }
 957
 958 static void
 959 ttydevsw_deffree(void *softc)
 960 {
 961
 962         panic("Terminal device freed without a free-handler");
 963 }
 964
 965 /*
 966  * TTY allocation and deallocation. TTY devices can be deallocated when
 967  * the driver doesn't use it anymore, when the TTY isn't a session's
 968  * controlling TTY and when the device node isn't opened through devfs.
 969  */
 970
 971 struct tty *
 972 tty_alloc(struct ttydevsw *tsw, void *sc)
 973 {
 974
 975         return (tty_alloc_mutex(tsw, sc, NULL));
 976 }
 977
 978 struct tty *
 979 tty_alloc_mutex(struct ttydevsw *tsw, void *sc, struct mtx *mutex)
 980 {
 981         struct tty *tp;
 982
 983         /* Make sure the driver defines all routines. */
 984 #define PATCH_FUNC(x) do {                              \
 985         if (tsw->tsw_ ## x == NULL)                     \
 986                 tsw->tsw_ ## x = ttydevsw_def ## x;     \
 987 } while (0)
 988         PATCH_FUNC(open);
 989         PATCH_FUNC(close);
 990         PATCH_FUNC(outwakeup);
 991         PATCH_FUNC(inwakeup);
 992         PATCH_FUNC(ioctl);
 993         PATCH_FUNC(cioctl);
 994         PATCH_FUNC(param);
 995         PATCH_FUNC(modem);
 996         PATCH_FUNC(mmap);
 997         PATCH_FUNC(pktnotify);
 998         PATCH_FUNC(free);
 999 #undef PATCH_FUNC
1000
1001         tp = malloc(sizeof(struct tty), M_TTY, M_WAITOK|M_ZERO);
1002         tp->t_devsw = tsw;
1003         tp->t_devswsoftc = sc;
1004         tp->t_flags = tsw->tsw_flags;
1005
1006         tty_init_termios(tp);
1007
1008         cv_init(&tp->t_inwait, "ttyin");
1009         cv_init(&tp->t_outwait, "ttyout");
1010         cv_init(&tp->t_outserwait, "ttyosr");
1011         cv_init(&tp->t_bgwait, "ttybg");
1012         cv_init(&tp->t_dcdwait, "ttydcd");
1013
1014         /* Allow drivers to use a custom mutex to lock the TTY. */
1015         if (mutex != NULL) {
1016                 tp->t_mtx = mutex;
1017         } else {
1018                 tp->t_mtx = &tp->t_mtxobj;
1019                 mtx_init(&tp->t_mtxobj, "ttymtx", NULL, MTX_DEF);
1020         }
1021
1022         knlist_init_mtx(&tp->t_inpoll.si_note, tp->t_mtx);
1023         knlist_init_mtx(&tp->t_outpoll.si_note, tp->t_mtx);
1024
1025         return (tp);
1026 }
1027
1028 static void
1029 tty_dealloc(void *arg)
1030 {
1031         struct tty *tp = arg;
1032
1033         /* Make sure we haven't leaked buffers. */
1034         MPASS(ttyinq_getsize(&tp->t_inq) == 0);
1035         MPASS(ttyoutq_getsize(&tp->t_outq) == 0);
1036
1037         seldrain(&tp->t_inpoll);
1038         seldrain(&tp->t_outpoll);
1039         knlist_destroy(&tp->t_inpoll.si_note);
1040         knlist_destroy(&tp->t_outpoll.si_note);
1041
1042         cv_destroy(&tp->t_inwait);
1043         cv_destroy(&tp->t_outwait);
1044         cv_destroy(&tp->t_bgwait);
1045         cv_destroy(&tp->t_dcdwait);
1046         cv_destroy(&tp->t_outserwait);
1047
1048         if (tp->t_mtx == &tp->t_mtxobj)
1049                 mtx_destroy(&tp->t_mtxobj);
1050         ttydevsw_free(tp);
1051         free(tp, M_TTY);
1052 }
1053
1054 static void
1055 tty_rel_free(struct tty *tp)
1056 {
1057         struct cdev *dev;
1058
1059         tty_lock_assert(tp, MA_OWNED);
1060
1061 #define TF_ACTIVITY     (TF_GONE|TF_OPENED|TF_HOOK|TF_OPENCLOSE)
1062         if (tp->t_sessioncnt != 0 || (tp->t_flags & TF_ACTIVITY) != TF_GONE) {
1063                 /* TTY is still in use. */
1064                 tty_unlock(tp);
1065                 return;
1066         }
1067
1068         /* TTY can be deallocated. */
1069         dev = tp->t_dev;
1070         tp->t_dev = NULL;
1071         tty_unlock(tp);
1072
1073         if (dev != NULL) {
1074                 sx_xlock(&tty_list_sx);
1075                 TAILQ_REMOVE(&tty_list, tp, t_list);
1076                 tty_list_count--;
1077                 sx_xunlock(&tty_list_sx);
1078                 destroy_dev_sched_cb(dev, tty_dealloc, tp);
1079         }
1080 }
1081
1082 void
1083 tty_rel_pgrp(struct tty *tp, struct pgrp *pg)
1084 {
1085         MPASS(tp->t_sessioncnt > 0);
1086         tty_lock_assert(tp, MA_OWNED);
1087
1088         if (tp->t_pgrp == pg)
1089                 tp->t_pgrp = NULL;
1090
1091         tty_unlock(tp);
1092 }
1093
1094 void
1095 tty_rel_sess(struct tty *tp, struct session *sess)
1096 {
1097         MPASS(tp->t_sessioncnt > 0);
1098
1099         /* Current session has left. */
1100         if (tp->t_session == sess) {
1101                 tp->t_session = NULL;
1102                 MPASS(tp->t_pgrp == NULL);
1103         }
1104         tp->t_sessioncnt--;
1105         tty_rel_free(tp);
1106 }
1107
1108 void
1109 tty_rel_gone(struct tty *tp)
1110 {
1111         MPASS(!tty_gone(tp));
1112
1113         /* Simulate carrier removal. */
1114         ttydisc_modem(tp, 0);
1115
1116         /* Wake up all blocked threads. */
1117         tty_wakeup(tp, FREAD|FWRITE);
1118         cv_broadcast(&tp->t_bgwait);
1119         cv_broadcast(&tp->t_dcdwait);
1120
1121         tp->t_flags |= TF_GONE;
1122         tty_rel_free(tp);
1123 }
1124
1125 /*
1126  * Exposing information about current TTY's through sysctl
1127  */
1128
1129 static void
1130 tty_to_xtty(struct tty *tp, struct xtty *xt)
1131 {
1132         tty_lock_assert(tp, MA_OWNED);
1133
1134         xt->xt_size = sizeof(struct xtty);
1135         xt->xt_insize = ttyinq_getsize(&tp->t_inq);
1136         xt->xt_incc = ttyinq_bytescanonicalized(&tp->t_inq);
1137         xt->xt_inlc = ttyinq_bytesline(&tp->t_inq);
1138         xt->xt_inlow = tp->t_inlow;
1139         xt->xt_outsize = ttyoutq_getsize(&tp->t_outq);
1140         xt->xt_outcc = ttyoutq_bytesused(&tp->t_outq);
1141         xt->xt_outlow = tp->t_outlow;
1142         xt->xt_column = tp->t_column;
1143         xt->xt_pgid = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
1144         xt->xt_sid = tp->t_session ? tp->t_session->s_sid : 0;
1145         xt->xt_flags = tp->t_flags;
1146         xt->xt_dev = tp->t_dev ? dev2udev(tp->t_dev) : NODEV;
1147 }
1148
1149 static int
1150 sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
1151 {
1152         unsigned long lsize;
1153         struct xtty *xtlist, *xt;
1154         struct tty *tp;
1155         int error;
1156
1157         sx_slock(&tty_list_sx);
1158         lsize = tty_list_count * sizeof(struct xtty);
1159         if (lsize == 0) {
1160                 sx_sunlock(&tty_list_sx);
1161                 return (0);
1162         }
1163
1164         xtlist = xt = malloc(lsize, M_TTY, M_WAITOK);
1165
1166         TAILQ_FOREACH(tp, &tty_list, t_list) {
1167                 tty_lock(tp);
1168                 tty_to_xtty(tp, xt);
1169                 tty_unlock(tp);
1170                 xt++;
1171         }
1172         sx_sunlock(&tty_list_sx);
1173
1174         error = SYSCTL_OUT(req, xtlist, lsize);
1175         free(xtlist, M_TTY);
1176         return (error);
1177 }
1178
1179 SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
1180         0, 0, sysctl_kern_ttys, "S,xtty", "List of TTYs");
1181
1182 /*
1183  * Device node creation. Device has been set up, now we can expose it to
1184  * the user.
1185  */
1186
1187 static int
1188 tty_vmakedevf(struct tty *tp, struct ucred *cred, int flags,
1189     const char *fmt, va_list ap)
1190 {
1191         struct cdev *dev, *init, *lock, *cua, *cinit, *clock;
1192         const char *prefix = "tty";
1193         char name[SPECNAMELEN - 3]; /* for "tty" and "cua". */
1194         uid_t uid;
1195         gid_t gid;
1196         mode_t mode;
1197         int error;
1198
1199         /* Remove "tty" prefix from devices like PTY's. */
1200         if (tp->t_flags & TF_NOPREFIX)
1201                 prefix = "";
1202
1203         vsnrprintf(name, sizeof name, 32, fmt, ap);
1204
1205         if (cred == NULL) {
1206                 /* System device. */
1207                 uid = UID_ROOT;
1208                 gid = GID_WHEEL;
1209                 mode = S_IRUSR|S_IWUSR;
1210         } else {
1211                 /* User device. */
1212                 uid = cred->cr_ruid;
1213                 gid = GID_TTY;
1214                 mode = S_IRUSR|S_IWUSR|S_IWGRP;
1215         }
1216
1217         flags = flags & TTYMK_CLONING ? MAKEDEV_REF : 0;
1218         flags |= MAKEDEV_CHECKNAME;
1219
1220         /* Master call-in device. */
1221         error = make_dev_p(flags, &dev, &ttydev_cdevsw, cred, uid, gid, mode,
1222             "%s%s", prefix, name);
1223         if (error)
1224                 return (error);
1225         dev->si_drv1 = tp;
1226         wakeup(&dev->si_drv1);
1227         tp->t_dev = dev;
1228
1229         init = lock = cua = cinit = clock = NULL;
1230
1231         /* Slave call-in devices. */
1232         if (tp->t_flags & TF_INITLOCK) {
1233                 error = make_dev_p(flags, &init, &ttyil_cdevsw, cred, uid,
1234                     gid, mode, "%s%s.init", prefix, name);
1235                 if (error)
1236                         goto fail;
1237                 dev_depends(dev, init);
1238                 dev2unit(init) = TTYUNIT_INIT;
1239                 init->si_drv1 = tp;
1240                 wakeup(&init->si_drv1);
1241                 init->si_drv2 = &tp->t_termios_init_in;
1242
1243                 error = make_dev_p(flags, &lock, &ttyil_cdevsw, cred, uid,
1244                     gid, mode, "%s%s.lock", prefix, name);
1245                 if (error)
1246                         goto fail;
1247                 dev_depends(dev, lock);
1248                 dev2unit(lock) = TTYUNIT_LOCK;
1249                 lock->si_drv1 = tp;
1250                 wakeup(&lock->si_drv1);
1251                 lock->si_drv2 = &tp->t_termios_lock_in;
1252         }
1253
1254         /* Call-out devices. */
1255         if (tp->t_flags & TF_CALLOUT) {
1256                 error = make_dev_p(flags, &cua, &ttydev_cdevsw, cred,
1257                     UID_UUCP, GID_DIALER, 0660, "cua%s", name);
1258                 if (error)
1259                         goto fail;
1260                 dev_depends(dev, cua);
1261                 dev2unit(cua) = TTYUNIT_CALLOUT;
1262                 cua->si_drv1 = tp;
1263                 wakeup(&cua->si_drv1);
1264
1265                 /* Slave call-out devices. */
1266                 if (tp->t_flags & TF_INITLOCK) {
1267                         error = make_dev_p(flags, &cinit, &ttyil_cdevsw, cred,
1268                             UID_UUCP, GID_DIALER, 0660, "cua%s.init", name);
1269                         if (error)
1270                                 goto fail;
1271                         dev_depends(dev, cinit);
1272                         dev2unit(cinit) = TTYUNIT_CALLOUT | TTYUNIT_INIT;
1273                         cinit->si_drv1 = tp;
1274                         wakeup(&cinit->si_drv1);
1275                         cinit->si_drv2 = &tp->t_termios_init_out;
1276
1277                         error = make_dev_p(flags, &clock, &ttyil_cdevsw, cred,
1278                             UID_UUCP, GID_DIALER, 0660, "cua%s.lock", name);
1279                         if (error)
1280                                 goto fail;
1281                         dev_depends(dev, clock);
1282                         dev2unit(clock) = TTYUNIT_CALLOUT | TTYUNIT_LOCK;
1283                         clock->si_drv1 = tp;
1284                         wakeup(&clock->si_drv1);
1285                         clock->si_drv2 = &tp->t_termios_lock_out;
1286                 }
1287         }
1288
1289         sx_xlock(&tty_list_sx);
1290         TAILQ_INSERT_TAIL(&tty_list, tp, t_list);
1291         tty_list_count++;
1292         sx_xunlock(&tty_list_sx);
1293
1294         return (0);
1295
1296 fail:
1297         destroy_dev(dev);
1298         if (init)
1299                 destroy_dev(init);
1300         if (lock)
1301                 destroy_dev(lock);
1302         if (cinit)
1303                 destroy_dev(cinit);
1304         if (clock)
1305                 destroy_dev(clock);
1306
1307         return (error);
1308 }
1309
1310 int
1311 tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
1312     const char *fmt, ...)
1313 {
1314         va_list ap;
1315         int error;
1316
1317         va_start(ap, fmt);
1318         error = tty_vmakedevf(tp, cred, flags, fmt, ap);
1319         va_end(ap);
1320
1321         return (error);
1322 }
1323
1324 void
1325 tty_makedev(struct tty *tp, struct ucred *cred, const char *fmt, ...)
1326 {
1327         va_list ap;
1328
1329         va_start(ap, fmt);
1330         (void) tty_vmakedevf(tp, cred, 0, fmt, ap);
1331         va_end(ap);
1332 }
1333
1334 /*
1335  * Signalling processes.
1336  */
1337
1338 void
1339 tty_signal_sessleader(struct tty *tp, int sig)
1340 {
1341         struct proc *p;
1342
1343         tty_lock_assert(tp, MA_OWNED);
1344         MPASS(sig >= 1 && sig < NSIG);
1345
1346         /* Make signals start output again. */
1347         tp->t_flags &= ~TF_STOPPED;
1348
1349         if (tp->t_session != NULL && tp->t_session->s_leader != NULL) {
1350                 p = tp->t_session->s_leader;
1351                 PROC_LOCK(p);
1352                 kern_psignal(p, sig);
1353                 PROC_UNLOCK(p);
1354         }
1355 }
1356
1357 void
1358 tty_signal_pgrp(struct tty *tp, int sig)
1359 {
1360         ksiginfo_t ksi;
1361
1362         tty_lock_assert(tp, MA_OWNED);
1363         MPASS(sig >= 1 && sig < NSIG);
1364
1365         /* Make signals start output again. */
1366         tp->t_flags &= ~TF_STOPPED;
1367
1368         if (sig == SIGINFO && !(tp->t_termios.c_lflag & NOKERNINFO))
1369                 tty_info(tp);
1370         if (tp->t_pgrp != NULL) {
1371                 ksiginfo_init(&ksi);
1372                 ksi.ksi_signo = sig;
1373                 ksi.ksi_code = SI_KERNEL;
1374                 PGRP_LOCK(tp->t_pgrp);
1375                 pgsignal(tp->t_pgrp, sig, 1, &ksi);
1376                 PGRP_UNLOCK(tp->t_pgrp);
1377         }
1378 }
1379
1380 void
1381 tty_wakeup(struct tty *tp, int flags)
1382 {
1383         if (tp->t_flags & TF_ASYNC && tp->t_sigio != NULL)
1384                 pgsigio(&tp->t_sigio, SIGIO, (tp->t_session != NULL));
1385
1386         if (flags & FWRITE) {
1387                 cv_broadcast(&tp->t_outwait);
1388                 selwakeup(&tp->t_outpoll);
1389                 KNOTE_LOCKED(&tp->t_outpoll.si_note, 0);
1390         }
1391         if (flags & FREAD) {
1392                 cv_broadcast(&tp->t_inwait);
1393                 selwakeup(&tp->t_inpoll);
1394                 KNOTE_LOCKED(&tp->t_inpoll.si_note, 0);
1395         }
1396 }
1397
1398 int
1399 tty_wait(struct tty *tp, struct cv *cv)
1400 {
1401         int error;
1402         int revokecnt = tp->t_revokecnt;
1403
1404         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1405         MPASS(!tty_gone(tp));
1406
1407         error = cv_wait_sig(cv, tp->t_mtx);
1408
1409         /* Bail out when the device slipped away. */
1410         if (tty_gone(tp))
1411                 return (ENXIO);
1412
1413         /* Restart the system call when we may have been revoked. */
1414         if (tp->t_revokecnt != revokecnt)
1415                 return (ERESTART);
1416
1417         return (error);
1418 }
1419
1420 int
1421 tty_timedwait(struct tty *tp, struct cv *cv, int hz)
1422 {
1423         int error;
1424         int revokecnt = tp->t_revokecnt;
1425
1426         tty_lock_assert(tp, MA_OWNED|MA_NOTRECURSED);
1427         MPASS(!tty_gone(tp));
1428
1429         error = cv_timedwait_sig(cv, tp->t_mtx, hz);
1430
1431         /* Bail out when the device slipped away. */
1432         if (tty_gone(tp))
1433                 return (ENXIO);
1434
1435         /* Restart the system call when we may have been revoked. */
1436         if (tp->t_revokecnt != revokecnt)
1437                 return (ERESTART);
1438
1439         return (error);
1440 }
1441
1442 void
1443 tty_flush(struct tty *tp, int flags)
1444 {
1445         if (flags & FWRITE) {
1446                 tp->t_flags &= ~TF_HIWAT_OUT;
1447                 ttyoutq_flush(&tp->t_outq);
1448                 tty_wakeup(tp, FWRITE);
1449                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHWRITE);
1450         }
1451         if (flags & FREAD) {
1452                 tty_hiwat_in_unblock(tp);
1453                 ttyinq_flush(&tp->t_inq);
1454                 ttydevsw_inwakeup(tp);
1455                 ttydevsw_pktnotify(tp, TIOCPKT_FLUSHREAD);
1456         }
1457 }
1458
1459 void
1460 tty_set_winsize(struct tty *tp, const struct winsize *wsz)
1461 {
1462
1463         if (memcmp(&tp->t_winsize, wsz, sizeof(*wsz)) == 0)
1464                 return;
1465         tp->t_winsize = *wsz;
1466         tty_signal_pgrp(tp, SIGWINCH);
1467 }
1468
1469 static int
1470 tty_generic_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
1471     struct thread *td)
1472 {
1473         int error;
1474
1475         switch (cmd) {
1476         /*
1477          * Modem commands.
1478          * The SER_* and TIOCM_* flags are the same, but one bit
1479          * shifted. I don't know why.
1480          */
1481         case TIOCSDTR:
1482                 ttydevsw_modem(tp, SER_DTR, 0);
1483                 return (0);
1484         case TIOCCDTR:
1485                 ttydevsw_modem(tp, 0, SER_DTR);
1486                 return (0);
1487         case TIOCMSET: {
1488                 int bits = *(int *)data;
1489                 ttydevsw_modem(tp,
1490                     (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1,
1491                     ((~bits) & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1492                 return (0);
1493         }
1494         case TIOCMBIS: {
1495                 int bits = *(int *)data;
1496                 ttydevsw_modem(tp, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1, 0);
1497                 return (0);
1498         }
1499         case TIOCMBIC: {
1500                 int bits = *(int *)data;
1501                 ttydevsw_modem(tp, 0, (bits & (TIOCM_DTR | TIOCM_RTS)) >> 1);
1502                 return (0);
1503         }
1504         case TIOCMGET:
1505                 *(int *)data = TIOCM_LE + (ttydevsw_modem(tp, 0, 0) << 1);
1506                 return (0);
1507
1508         case FIOASYNC:
1509                 if (*(int *)data)
1510                         tp->t_flags |= TF_ASYNC;
1511                 else
1512                         tp->t_flags &= ~TF_ASYNC;
1513                 return (0);
1514         case FIONBIO:
1515                 /* This device supports non-blocking operation. */
1516                 return (0);
1517         case FIONREAD:
1518                 *(int *)data = ttyinq_bytescanonicalized(&tp->t_inq);
1519                 return (0);
1520         case FIONWRITE:
1521         case TIOCOUTQ:
1522                 *(int *)data = ttyoutq_bytesused(&tp->t_outq);
1523                 return (0);
1524         case FIOSETOWN:
1525                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1526                         /* Not allowed to set ownership. */
1527                         return (ENOTTY);
1528
1529                 /* Temporarily unlock the TTY to set ownership. */
1530                 tty_unlock(tp);
1531                 error = fsetown(*(int *)data, &tp->t_sigio);
1532                 tty_lock(tp);
1533                 return (error);
1534         case FIOGETOWN:
1535                 if (tp->t_session != NULL && !tty_is_ctty(tp, td->td_proc))
1536                         /* Not allowed to set ownership. */
1537                         return (ENOTTY);
1538
1539                 /* Get ownership. */
1540                 *(int *)data = fgetown(&tp->t_sigio);
1541                 return (0);
1542         case TIOCGETA:
1543                 /* Obtain terminal flags through tcgetattr(). */
1544                 *(struct termios*)data = tp->t_termios;
1545                 return (0);
1546         case TIOCSETA:
1547         case TIOCSETAW:
1548         case TIOCSETAF: {
1549                 struct termios *t = data;
1550
1551                 /*
1552                  * Who makes up these funny rules? According to POSIX,
1553                  * input baud rate is set equal to the output baud rate
1554                  * when zero.
1555                  */
1556                 if (t->c_ispeed == 0)
1557                         t->c_ispeed = t->c_ospeed;
1558
1559                 /* Discard any unsupported bits. */
1560                 t->c_iflag &= TTYSUP_IFLAG;
1561                 t->c_oflag &= TTYSUP_OFLAG;
1562                 t->c_lflag &= TTYSUP_LFLAG;
1563                 t->c_cflag &= TTYSUP_CFLAG;
1564
1565                 /* Set terminal flags through tcsetattr(). */
1566                 if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
1567                         error = tty_drain(tp, 0);
1568                         if (error)
1569                                 return (error);
1570                         if (cmd == TIOCSETAF)
1571                                 tty_flush(tp, FREAD);
1572                 }
1573
1574                 /*
1575                  * Only call param() when the flags really change.
1576                  */
1577                 if ((t->c_cflag & CIGNORE) == 0 &&
1578                     (tp->t_termios.c_cflag != t->c_cflag ||
1579                     ((tp->t_termios.c_iflag ^ t->c_iflag) &
1580                     (IXON|IXOFF|IXANY)) ||
1581                     tp->t_termios.c_ispeed != t->c_ispeed ||
1582                     tp->t_termios.c_ospeed != t->c_ospeed)) {
1583                         error = ttydevsw_param(tp, t);
1584                         if (error)
1585                                 return (error);
1586
1587                         /* XXX: CLOCAL? */
1588
1589                         tp->t_termios.c_cflag = t->c_cflag & ~CIGNORE;
1590                         tp->t_termios.c_ispeed = t->c_ispeed;
1591                         tp->t_termios.c_ospeed = t->c_ospeed;
1592
1593                         /* Baud rate has changed - update watermarks. */
1594                         tty_watermarks(tp);
1595                 }
1596
1597                 /* Copy new non-device driver parameters. */
1598                 tp->t_termios.c_iflag = t->c_iflag;
1599                 tp->t_termios.c_oflag = t->c_oflag;
1600                 tp->t_termios.c_lflag = t->c_lflag;
1601                 memcpy(&tp->t_termios.c_cc, t->c_cc, sizeof t->c_cc);
1602
1603                 ttydisc_optimize(tp);
1604
1605                 if ((t->c_lflag & ICANON) == 0) {
1606                         /*
1607                          * When in non-canonical mode, wake up all
1608                          * readers. Canonicalize any partial input. VMIN
1609                          * and VTIME could also be adjusted.
1610                          */
1611                         ttyinq_canonicalize(&tp->t_inq);
1612                         tty_wakeup(tp, FREAD);
1613                 }
1614
1615                 /*
1616                  * For packet mode: notify the PTY consumer that VSTOP
1617                  * and VSTART may have been changed.
1618                  */
1619                 if (tp->t_termios.c_iflag & IXON &&
1620                     tp->t_termios.c_cc[VSTOP] == CTRL('S') &&
1621                     tp->t_termios.c_cc[VSTART] == CTRL('Q'))
1622                         ttydevsw_pktnotify(tp, TIOCPKT_DOSTOP);
1623                 else
1624                         ttydevsw_pktnotify(tp, TIOCPKT_NOSTOP);
1625                 return (0);
1626         }
1627         case TIOCGETD:
1628                 /* For compatibility - we only support TTYDISC. */
1629                 *(int *)data = TTYDISC;
1630                 return (0);
1631         case TIOCGPGRP:
1632                 if (!tty_is_ctty(tp, td->td_proc))
1633                         return (ENOTTY);
1634
1635                 if (tp->t_pgrp != NULL)
1636                         *(int *)data = tp->t_pgrp->pg_id;
1637                 else
1638                         *(int *)data = NO_PID;
1639                 return (0);
1640         case TIOCGSID:
1641                 if (!tty_is_ctty(tp, td->td_proc))
1642                         return (ENOTTY);
1643
1644                 MPASS(tp->t_session);
1645                 *(int *)data = tp->t_session->s_sid;
1646                 return (0);
1647         case TIOCSCTTY: {
1648                 struct proc *p = td->td_proc;
1649
1650                 /* XXX: This looks awful. */
1651                 tty_unlock(tp);
1652                 sx_xlock(&proctree_lock);
1653                 tty_lock(tp);
1654
1655                 if (!SESS_LEADER(p)) {
1656                         /* Only the session leader may do this. */
1657                         sx_xunlock(&proctree_lock);
1658                         return (EPERM);
1659                 }
1660
1661                 if (tp->t_session != NULL && tp->t_session == p->p_session) {
1662                         /* This is already our controlling TTY. */
1663                         sx_xunlock(&proctree_lock);
1664                         return (0);
1665                 }
1666
1667                 if (p->p_session->s_ttyp != NULL ||
1668                     (tp->t_session != NULL && tp->t_session->s_ttyvp != NULL &&
1669                     tp->t_session->s_ttyvp->v_type != VBAD)) {
1670                         /*
1671                          * There is already a relation between a TTY and
1672                          * a session, or the caller is not the session
1673                          * leader.
1674                          *
1675                          * Allow the TTY to be stolen when the vnode is
1676                          * invalid, but the reference to the TTY is
1677                          * still active.  This allows immediate reuse of
1678                          * TTYs of which the session leader has been
1679                          * killed or the TTY revoked.
1680                          */
1681                         sx_xunlock(&proctree_lock);
1682                         return (EPERM);
1683                 }
1684
1685                 /* Connect the session to the TTY. */
1686                 tp->t_session = p->p_session;
1687                 tp->t_session->s_ttyp = tp;
1688                 tp->t_sessioncnt++;
1689                 sx_xunlock(&proctree_lock);
1690
1691                 /* Assign foreground process group. */
1692                 tp->t_pgrp = p->p_pgrp;
1693                 PROC_LOCK(p);
1694                 p->p_flag |= P_CONTROLT;
1695                 PROC_UNLOCK(p);
1696
1697                 return (0);
1698         }
1699         case TIOCSPGRP: {
1700                 struct pgrp *pg;
1701
1702                 /*
1703                  * XXX: Temporarily unlock the TTY to locate the process
1704                  * group. This code would be lot nicer if we would ever
1705                  * decompose proctree_lock.
1706                  */
1707                 tty_unlock(tp);
1708                 sx_slock(&proctree_lock);
1709                 pg = pgfind(*(int *)data);
1710                 if (pg != NULL)
1711                         PGRP_UNLOCK(pg);
1712                 if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
1713                         sx_sunlock(&proctree_lock);
1714                         tty_lock(tp);
1715                         return (EPERM);
1716                 }
1717                 tty_lock(tp);
1718
1719                 /*
1720                  * Determine if this TTY is the controlling TTY after
1721                  * relocking the TTY.
1722                  */
1723                 if (!tty_is_ctty(tp, td->td_proc)) {
1724                         sx_sunlock(&proctree_lock);
1725                         return (ENOTTY);
1726                 }
1727                 tp->t_pgrp = pg;
1728                 sx_sunlock(&proctree_lock);
1729
1730                 /* Wake up the background process groups. */
1731                 cv_broadcast(&tp->t_bgwait);
1732                 return (0);
1733         }
1734         case TIOCFLUSH: {
1735                 int flags = *(int *)data;
1736
1737                 if (flags == 0)
1738                         flags = (FREAD|FWRITE);
1739                 else
1740                         flags &= (FREAD|FWRITE);
1741                 tty_flush(tp, flags);
1742                 return (0);
1743         }
1744         case TIOCDRAIN:
1745                 /* Drain TTY output. */
1746                 return tty_drain(tp, 0);
1747         case TIOCCONS:
1748                 /* Set terminal as console TTY. */
1749                 if (*(int *)data) {
1750                         error = priv_check(td, PRIV_TTY_CONSOLE);
1751                         if (error)
1752                                 return (error);
1753
1754                         /*
1755                          * XXX: constty should really need to be locked!
1756                          * XXX: allow disconnected constty's to be stolen!
1757                          */
1758
1759                         if (constty == tp)
1760                                 return (0);
1761                         if (constty != NULL)
1762                                 return (EBUSY);
1763
1764                         tty_unlock(tp);
1765                         constty_set(tp);
1766                         tty_lock(tp);
1767                 } else if (constty == tp) {
1768                         constty_clear();
1769                 }
1770                 return (0);
1771         case TIOCGWINSZ:
1772                 /* Obtain window size. */
1773                 *(struct winsize*)data = tp->t_winsize;
1774                 return (0);
1775         case TIOCSWINSZ:
1776                 /* Set window size. */
1777                 tty_set_winsize(tp, data);
1778                 return (0);
1779         case TIOCEXCL:
1780                 tp->t_flags |= TF_EXCLUDE;
1781                 return (0);
1782         case TIOCNXCL:
1783                 tp->t_flags &= ~TF_EXCLUDE;
1784                 return (0);
1785         case TIOCSTOP:
1786                 tp->t_flags |= TF_STOPPED;
1787                 ttydevsw_pktnotify(tp, TIOCPKT_STOP);
1788                 return (0);
1789         case TIOCSTART:
1790                 tp->t_flags &= ~TF_STOPPED;
1791                 ttydevsw_outwakeup(tp);
1792                 ttydevsw_pktnotify(tp, TIOCPKT_START);
1793                 return (0);
1794         case TIOCSTAT:
1795                 tty_info(tp);
1796                 return (0);
1797         case TIOCSTI:
1798                 if ((fflag & FREAD) == 0 && priv_check(td, PRIV_TTY_STI))
1799                         return (EPERM);
1800                 if (!tty_is_ctty(tp, td->td_proc) &&
1801                     priv_check(td, PRIV_TTY_STI))
1802                         return (EACCES);
1803                 ttydisc_rint(tp, *(char *)data, 0);
1804                 ttydisc_rint_done(tp);
1805                 return (0);
1806         }
1807
1808 #ifdef COMPAT_43TTY
1809         return tty_ioctl_compat(tp, cmd, data, fflag, td);
1810 #else /* !COMPAT_43TTY */
1811         return (ENOIOCTL);
1812 #endif /* COMPAT_43TTY */
1813 }
1814
1815 int
1816 tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag, struct thread *td)
1817 {
1818         int error;
1819
1820         tty_lock_assert(tp, MA_OWNED);
1821
1822         if (tty_gone(tp))
1823                 return (ENXIO);
1824
1825         error = ttydevsw_ioctl(tp, cmd, data, td);
1826         if (error == ENOIOCTL)
1827                 error = tty_generic_ioctl(tp, cmd, data, fflag, td);
1828
1829         return (error);
1830 }
1831
1832 dev_t
1833 tty_udev(struct tty *tp)
1834 {
1835         if (tp->t_dev)
1836                 return dev2udev(tp->t_dev);
1837         else
1838                 return NODEV;
1839 }
1840
1841 int
1842 tty_checkoutq(struct tty *tp)
1843 {
1844
1845         /* 256 bytes should be enough to print a log message. */
1846         return (ttyoutq_bytesleft(&tp->t_outq) >= 256);
1847 }
1848
1849 void
1850 tty_hiwat_in_block(struct tty *tp)
1851 {
1852
1853         if ((tp->t_flags & TF_HIWAT_IN) == 0 &&
1854             tp->t_termios.c_iflag & IXOFF &&
1855             tp->t_termios.c_cc[VSTOP] != _POSIX_VDISABLE) {
1856                 /*
1857                  * Input flow control. Only enter the high watermark when we
1858                  * can successfully store the VSTOP character.
1859                  */
1860                 if (ttyoutq_write_nofrag(&tp->t_outq,
1861                     &tp->t_termios.c_cc[VSTOP], 1) == 0)
1862                         tp->t_flags |= TF_HIWAT_IN;
1863         } else {
1864                 /* No input flow control. */
1865                 tp->t_flags |= TF_HIWAT_IN;
1866         }
1867 }
1868
1869 void
1870 tty_hiwat_in_unblock(struct tty *tp)
1871 {
1872
1873         if (tp->t_flags & TF_HIWAT_IN &&
1874             tp->t_termios.c_iflag & IXOFF &&
1875             tp->t_termios.c_cc[VSTART] != _POSIX_VDISABLE) {
1876                 /*
1877                  * Input flow control. Only leave the high watermark when we
1878                  * can successfully store the VSTART character.
1879                  */
1880                 if (ttyoutq_write_nofrag(&tp->t_outq,
1881                     &tp->t_termios.c_cc[VSTART], 1) == 0)
1882                         tp->t_flags &= ~TF_HIWAT_IN;
1883         } else {
1884                 /* No input flow control. */
1885                 tp->t_flags &= ~TF_HIWAT_IN;
1886         }
1887
1888         if (!tty_gone(tp))
1889                 ttydevsw_inwakeup(tp);
1890 }
1891
1892 /*
1893  * TTY hooks interface.
1894  */
1895
1896 static int
1897 ttyhook_defrint(struct tty *tp, char c, int flags)
1898 {
1899
1900         if (ttyhook_rint_bypass(tp, &c, 1) != 1)
1901                 return (-1);
1902
1903         return (0);
1904 }
1905
1906 int
1907 ttyhook_register(struct tty **rtp, struct proc *p, int fd,
1908     struct ttyhook *th, void *softc)
1909 {
1910         struct tty *tp;
1911         struct file *fp;
1912         struct cdev *dev;
1913         struct cdevsw *cdp;
1914         struct filedesc *fdp;
1915         cap_rights_t rights;
1916         int error, ref;
1917
1918         /* Validate the file descriptor. */
1919         fdp = p->p_fd;
1920         error = fget_unlocked(fdp, fd, cap_rights_init(&rights, CAP_TTYHOOK),
1921             0, &fp, NULL);
1922         if (error != 0)
1923                 return (error);
1924         if (fp->f_ops == &badfileops) {
1925                 error = EBADF;
1926                 goto done1;
1927         }
1928
1929         /*
1930          * Make sure the vnode is bound to a character device.
1931          * Unlocked check for the vnode type is ok there, because we
1932          * only shall prevent calling devvn_refthread on the file that
1933          * never has been opened over a character device.
1934          */
1935         if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
1936                 error = EINVAL;
1937                 goto done1;
1938         }
1939
1940         /* Make sure it is a TTY. */
1941         cdp = devvn_refthread(fp->f_vnode, &dev, &ref);
1942         if (cdp == NULL) {
1943                 error = ENXIO;
1944                 goto done1;
1945         }
1946         if (dev != fp->f_data) {
1947                 error = ENXIO;
1948                 goto done2;
1949         }
1950         if (cdp != &ttydev_cdevsw) {
1951                 error = ENOTTY;
1952                 goto done2;
1953         }
1954         tp = dev->si_drv1;
1955
1956         /* Try to attach the hook to the TTY. */
1957         error = EBUSY;
1958         tty_lock(tp);
1959         MPASS((tp->t_hook == NULL) == ((tp->t_flags & TF_HOOK) == 0));
1960         if (tp->t_flags & TF_HOOK)
1961                 goto done3;
1962
1963         tp->t_flags |= TF_HOOK;
1964         tp->t_hook = th;
1965         tp->t_hooksoftc = softc;
1966         *rtp = tp;
1967         error = 0;
1968
1969         /* Maybe we can switch into bypass mode now. */
1970         ttydisc_optimize(tp);
1971
1972         /* Silently convert rint() calls to rint_bypass() when possible. */
1973         if (!ttyhook_hashook(tp, rint) && ttyhook_hashook(tp, rint_bypass))
1974                 th->th_rint = ttyhook_defrint;
1975
1976 done3:  tty_unlock(tp);
1977 done2:  dev_relthread(dev, ref);
1978 done1:  fdrop(fp, curthread);
1979         return (error);
1980 }
1981
1982 void
1983 ttyhook_unregister(struct tty *tp)
1984 {
1985
1986         tty_lock_assert(tp, MA_OWNED);
1987         MPASS(tp->t_flags & TF_HOOK);
1988
1989         /* Disconnect the hook. */
1990         tp->t_flags &= ~TF_HOOK;
1991         tp->t_hook = NULL;
1992
1993         /* Maybe we need to leave bypass mode. */
1994         ttydisc_optimize(tp);
1995
1996         /* Maybe deallocate the TTY as well. */
1997         tty_rel_free(tp);
1998 }
1999
2000 /*
2001  * /dev/console handling.
2002  */
2003
2004 static int
2005 ttyconsdev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
2006 {
2007         struct tty *tp;
2008
2009         /* System has no console device. */
2010         if (dev_console_filename == NULL)
2011                 return (ENXIO);
2012
2013         /* Look up corresponding TTY by device name. */
2014         sx_slock(&tty_list_sx);
2015         TAILQ_FOREACH(tp, &tty_list, t_list) {
2016                 if (strcmp(dev_console_filename, tty_devname(tp)) == 0) {
2017                         dev_console->si_drv1 = tp;
2018                         break;
2019                 }
2020         }
2021         sx_sunlock(&tty_list_sx);
2022
2023         /* System console has no TTY associated. */
2024         if (dev_console->si_drv1 == NULL)
2025                 return (ENXIO);
2026
2027         return (ttydev_open(dev, oflags, devtype, td));
2028 }
2029
2030 static int
2031 ttyconsdev_write(struct cdev *dev, struct uio *uio, int ioflag)
2032 {
2033
2034         log_console(uio);
2035
2036         return (ttydev_write(dev, uio, ioflag));
2037 }
2038
2039 /*
2040  * /dev/console is a little different than normal TTY's.  When opened,
2041  * it determines which TTY to use.  When data gets written to it, it
2042  * will be logged in the kernel message buffer.
2043  */
2044 static struct cdevsw ttyconsdev_cdevsw = {
2045         .d_version      = D_VERSION,
2046         .d_open         = ttyconsdev_open,
2047         .d_close        = ttydev_close,
2048         .d_read         = ttydev_read,
2049         .d_write        = ttyconsdev_write,
2050         .d_ioctl        = ttydev_ioctl,
2051         .d_kqfilter     = ttydev_kqfilter,
2052         .d_poll         = ttydev_poll,
2053         .d_mmap         = ttydev_mmap,
2054         .d_name         = "ttyconsdev",
2055         .d_flags        = D_TTY,
2056 };
2057
2058 static void
2059 ttyconsdev_init(void *unused)
2060 {
2061
2062         dev_console = make_dev_credf(MAKEDEV_ETERNAL, &ttyconsdev_cdevsw, 0,
2063             NULL, UID_ROOT, GID_WHEEL, 0600, "console");
2064 }
2065
2066 SYSINIT(tty, SI_SUB_DRIVERS, SI_ORDER_FIRST, ttyconsdev_init, NULL);
2067
2068 void
2069 ttyconsdev_select(const char *name)
2070 {
2071
2072         dev_console_filename = name;
2073 }
2074
2075 /*
2076  * Debugging routines.
2077  */
2078
2079 #include "opt_ddb.h"
2080 #ifdef DDB
2081 #include <ddb/ddb.h>
2082 #include <ddb/db_sym.h>
2083
2084 static struct {
2085         int flag;
2086         char val;
2087 } ttystates[] = {
2088 #if 0
2089         { TF_NOPREFIX,          'N' },
2090 #endif
2091         { TF_INITLOCK,          'I' },
2092         { TF_CALLOUT,           'C' },
2093
2094         /* Keep these together -> 'Oi' and 'Oo'. */
2095         { TF_OPENED,            'O' },
2096         { TF_OPENED_IN,         'i' },
2097         { TF_OPENED_OUT,        'o' },
2098         { TF_OPENED_CONS,       'c' },
2099
2100         { TF_GONE,              'G' },
2101         { TF_OPENCLOSE,         'B' },
2102         { TF_ASYNC,             'Y' },
2103         { TF_LITERAL,           'L' },
2104
2105         /* Keep these together -> 'Hi' and 'Ho'. */
2106         { TF_HIWAT,             'H' },
2107         { TF_HIWAT_IN,          'i' },
2108         { TF_HIWAT_OUT,         'o' },
2109
2110         { TF_STOPPED,           'S' },
2111         { TF_EXCLUDE,           'X' },
2112         { TF_BYPASS,            'l' },
2113         { TF_ZOMBIE,            'Z' },
2114         { TF_HOOK,              's' },
2115
2116         /* Keep these together -> 'bi' and 'bo'. */
2117         { TF_BUSY,              'b' },
2118         { TF_BUSY_IN,           'i' },
2119         { TF_BUSY_OUT,          'o' },
2120
2121         { 0,                    '\0'},
2122 };
2123
2124 #define TTY_FLAG_BITS \
2125         "\20\1NOPREFIX\2INITLOCK\3CALLOUT\4OPENED_IN\5OPENED_OUT\6GONE" \
2126         "\7OPENCLOSE\10ASYNC\11LITERAL\12HIWAT_IN\13HIWAT_OUT\14STOPPED" \
2127         "\15EXCLUDE\16BYPASS\17ZOMBIE\20HOOK"
2128
2129 #define DB_PRINTSYM(name, addr) \
2130         db_printf("%s  " #name ": ", sep); \
2131         db_printsym((db_addr_t) addr, DB_STGY_ANY); \
2132         db_printf("\n");
2133
2134 static void
2135 _db_show_devsw(const char *sep, const struct ttydevsw *tsw)
2136 {
2137         db_printf("%sdevsw: ", sep);
2138         db_printsym((db_addr_t)tsw, DB_STGY_ANY);
2139         db_printf(" (%p)\n", tsw);
2140         DB_PRINTSYM(open, tsw->tsw_open);
2141         DB_PRINTSYM(close, tsw->tsw_close);
2142         DB_PRINTSYM(outwakeup, tsw->tsw_outwakeup);
2143         DB_PRINTSYM(inwakeup, tsw->tsw_inwakeup);
2144         DB_PRINTSYM(ioctl, tsw->tsw_ioctl);
2145         DB_PRINTSYM(param, tsw->tsw_param);
2146         DB_PRINTSYM(modem, tsw->tsw_modem);
2147         DB_PRINTSYM(mmap, tsw->tsw_mmap);
2148         DB_PRINTSYM(pktnotify, tsw->tsw_pktnotify);
2149         DB_PRINTSYM(free, tsw->tsw_free);
2150 }
2151 static void
2152 _db_show_hooks(const char *sep, const struct ttyhook *th)
2153 {
2154         db_printf("%shook: ", sep);
2155         db_printsym((db_addr_t)th, DB_STGY_ANY);
2156         db_printf(" (%p)\n", th);
2157         if (th == NULL)
2158                 return;
2159         DB_PRINTSYM(rint, th->th_rint);
2160         DB_PRINTSYM(rint_bypass, th->th_rint_bypass);
2161         DB_PRINTSYM(rint_done, th->th_rint_done);
2162         DB_PRINTSYM(rint_poll, th->th_rint_poll);
2163         DB_PRINTSYM(getc_inject, th->th_getc_inject);
2164         DB_PRINTSYM(getc_capture, th->th_getc_capture);
2165         DB_PRINTSYM(getc_poll, th->th_getc_poll);
2166         DB_PRINTSYM(close, th->th_close);
2167 }
2168
2169 static void
2170 _db_show_termios(const char *name, const struct termios *t)
2171 {
2172
2173         db_printf("%s: iflag 0x%x oflag 0x%x cflag 0x%x "
2174             "lflag 0x%x ispeed %u ospeed %u\n", name,
2175             t->c_iflag, t->c_oflag, t->c_cflag, t->c_lflag,
2176             t->c_ispeed, t->c_ospeed);
2177 }
2178
2179 /* DDB command to show TTY statistics. */
2180 DB_SHOW_COMMAND(tty, db_show_tty)
2181 {
2182         struct tty *tp;
2183
2184         if (!have_addr) {
2185                 db_printf("usage: show tty <addr>\n");
2186                 return;
2187         }
2188         tp = (struct tty *)addr;
2189
2190         db_printf("0x%p: %s\n", tp, tty_devname(tp));
2191         db_printf("\tmtx: %p\n", tp->t_mtx);
2192         db_printf("\tflags: %b\n", tp->t_flags, TTY_FLAG_BITS);
2193         db_printf("\trevokecnt: %u\n", tp->t_revokecnt);
2194
2195         /* Buffering mechanisms. */
2196         db_printf("\tinq: %p begin %u linestart %u reprint %u end %u "
2197             "nblocks %u quota %u\n", &tp->t_inq, tp->t_inq.ti_begin,
2198             tp->t_inq.ti_linestart, tp->t_inq.ti_reprint, tp->t_inq.ti_end,
2199             tp->t_inq.ti_nblocks, tp->t_inq.ti_quota);
2200         db_printf("\toutq: %p begin %u end %u nblocks %u quota %u\n",
2201             &tp->t_outq, tp->t_outq.to_begin, tp->t_outq.to_end,
2202             tp->t_outq.to_nblocks, tp->t_outq.to_quota);
2203         db_printf("\tinlow: %zu\n", tp->t_inlow);
2204         db_printf("\toutlow: %zu\n", tp->t_outlow);
2205         _db_show_termios("\ttermios", &tp->t_termios);
2206         db_printf("\twinsize: row %u col %u xpixel %u ypixel %u\n",
2207             tp->t_winsize.ws_row, tp->t_winsize.ws_col,
2208             tp->t_winsize.ws_xpixel, tp->t_winsize.ws_ypixel);
2209         db_printf("\tcolumn: %u\n", tp->t_column);
2210         db_printf("\twritepos: %u\n", tp->t_writepos);
2211         db_printf("\tcompatflags: 0x%x\n", tp->t_compatflags);
2212
2213         /* Init/lock-state devices. */
2214         _db_show_termios("\ttermios_init_in", &tp->t_termios_init_in);
2215         _db_show_termios("\ttermios_init_out", &tp->t_termios_init_out);
2216         _db_show_termios("\ttermios_lock_in", &tp->t_termios_lock_in);
2217         _db_show_termios("\ttermios_lock_out", &tp->t_termios_lock_out);
2218
2219         /* Hooks */
2220         _db_show_devsw("\t", tp->t_devsw);
2221         _db_show_hooks("\t", tp->t_hook);
2222
2223         /* Process info. */
2224         db_printf("\tpgrp: %p gid %d jobc %d\n", tp->t_pgrp,
2225             tp->t_pgrp ? tp->t_pgrp->pg_id : 0,
2226             tp->t_pgrp ? tp->t_pgrp->pg_jobc : 0);
2227         db_printf("\tsession: %p", tp->t_session);
2228         if (tp->t_session != NULL)
2229             db_printf(" count %u leader %p tty %p sid %d login %s",
2230                 tp->t_session->s_count, tp->t_session->s_leader,
2231                 tp->t_session->s_ttyp, tp->t_session->s_sid,
2232                 tp->t_session->s_login);
2233         db_printf("\n");
2234         db_printf("\tsessioncnt: %u\n", tp->t_sessioncnt);
2235         db_printf("\tdevswsoftc: %p\n", tp->t_devswsoftc);
2236         db_printf("\thooksoftc: %p\n", tp->t_hooksoftc);
2237         db_printf("\tdev: %p\n", tp->t_dev);
2238 }
2239
2240 /* DDB command to list TTYs. */
2241 DB_SHOW_ALL_COMMAND(ttys, db_show_all_ttys)
2242 {
2243         struct tty *tp;
2244         size_t isiz, osiz;
2245         int i, j;
2246
2247         /* Make the output look like `pstat -t'. */
2248         db_printf("PTR        ");
2249 #if defined(__LP64__)
2250         db_printf("        ");
2251 #endif
2252         db_printf("      LINE   INQ  CAN  LIN  LOW  OUTQ  USE  LOW   "
2253             "COL  SESS  PGID STATE\n");
2254
2255         TAILQ_FOREACH(tp, &tty_list, t_list) {
2256                 isiz = tp->t_inq.ti_nblocks * TTYINQ_DATASIZE;
2257                 osiz = tp->t_outq.to_nblocks * TTYOUTQ_DATASIZE;
2258
2259                 db_printf("%p %10s %5zu %4u %4u %4zu %5zu %4u %4zu %5u %5d %5d ",
2260                     tp,
2261                     tty_devname(tp),
2262                     isiz,
2263                     tp->t_inq.ti_linestart - tp->t_inq.ti_begin,
2264                     tp->t_inq.ti_end - tp->t_inq.ti_linestart,
2265                     isiz - tp->t_inlow,
2266                     osiz,
2267                     tp->t_outq.to_end - tp->t_outq.to_begin,
2268                     osiz - tp->t_outlow,
2269                     MIN(tp->t_column, 99999),
2270                     tp->t_session ? tp->t_session->s_sid : 0,
2271                     tp->t_pgrp ? tp->t_pgrp->pg_id : 0);
2272
2273                 /* Flag bits. */
2274                 for (i = j = 0; ttystates[i].flag; i++)
2275                         if (tp->t_flags & ttystates[i].flag) {
2276                                 db_printf("%c", ttystates[i].val);
2277                                 j++;
2278                         }
2279                 if (j == 0)
2280                         db_printf("-");
2281                 db_printf("\n");
2282         }
2283 }
2284 #endif /* DDB */