sys/kern/tty_pty.c

   1 /*
   2  * Copyright (c) 1982, 1986, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)tty_pty.c   8.4 (Berkeley) 2/20/95
  34  * $FreeBSD: src/sys/kern/tty_pty.c,v 1.74.2.4 2002/02/20 19:58:13 dillon Exp $
  35  * $DragonFly: src/sys/kern/tty_pty.c,v 1.21 2008/08/13 10:29:38 swildner Exp $
  36  */
  37
  38 /*
  39  * Pseudo-teletype Driver
  40  * (Actually two drivers, requiring two dev_ops structures)
  41  */
  42 #include "use_pty.h"            /* XXX */
  43 #include "opt_compat.h"
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
  48 #include <sys/ioctl_compat.h>
  49 #endif
  50 #include <sys/proc.h>
  51 #include <sys/priv.h>
  52 #include <sys/tty.h>
  53 #include <sys/conf.h>
  54 #include <sys/fcntl.h>
  55 #include <sys/kernel.h>
  56 #include <sys/vnode.h>
  57 #include <sys/signalvar.h>
  58 #include <sys/malloc.h>
  59 #include <sys/device.h>
  60 #include <sys/thread2.h>
  61 #include <sys/devfs.h>
  62 #include <sys/stat.h>
  63 #include <sys/sysctl.h>
  64
  65 #define UNIX98_PTYS     1
  66
  67 MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
  68
  69 static void ptsstart (struct tty *tp);
  70 static void ptsstop (struct tty *tp, int rw);
  71 static void ptcwakeup (struct tty *tp, int flag);
  72 static void ptyinit (int n);
  73 static int  filt_ptcread (struct knote *kn, long hint);
  74 static void filt_ptcrdetach (struct knote *kn);
  75 static int  filt_ptcwrite (struct knote *kn, long hint);
  76 static void filt_ptcwdetach (struct knote *kn);
  77
  78 static  d_open_t        ptsopen;
  79 static  d_close_t       ptsclose;
  80 static  d_read_t        ptsread;
  81 static  d_write_t       ptswrite;
  82 static  d_ioctl_t       ptyioctl;
  83 static  d_open_t        ptcopen;
  84 static  d_close_t       ptcclose;
  85 static  d_read_t        ptcread;
  86 static  d_write_t       ptcwrite;
  87 static  d_kqfilter_t    ptckqfilter;
  88
  89 #ifdef UNIX98_PTYS
  90 DEVFS_DECLARE_CLONE_BITMAP(pty);
  91
  92 static  d_clone_t       ptyclone;
  93
  94 static int      pty_debug_level = 0;
  95
  96 static struct dev_ops pts98_ops = {
  97         { "pts98", 0, D_TTY | D_KQFILTER },
  98         .d_open =       ptsopen,
  99         .d_close =      ptsclose,
 100         .d_read =       ptsread,
 101         .d_write =      ptswrite,
 102         .d_ioctl =      ptyioctl,
 103         .d_kqfilter =   ttykqfilter,
 104         .d_revoke =     ttyrevoke
 105 };
 106
 107 static struct dev_ops ptc98_ops = {
 108         { "ptc98", 0, D_TTY | D_KQFILTER | D_MASTER },
 109         .d_open =       ptcopen,
 110         .d_close =      ptcclose,
 111         .d_read =       ptcread,
 112         .d_write =      ptcwrite,
 113         .d_ioctl =      ptyioctl,
 114         .d_kqfilter =   ptckqfilter,
 115         .d_revoke =     ttyrevoke
 116 };
 117 #endif
 118
 119 #define CDEV_MAJOR_S    5
 120 static struct dev_ops pts_ops = {
 121         { "pts", CDEV_MAJOR_S, D_TTY | D_KQFILTER },
 122         .d_open =       ptsopen,
 123         .d_close =      ptsclose,
 124         .d_read =       ptsread,
 125         .d_write =      ptswrite,
 126         .d_ioctl =      ptyioctl,
 127         .d_kqfilter =   ttykqfilter,
 128         .d_revoke =     ttyrevoke
 129 };
 130
 131 #define CDEV_MAJOR_C    6
 132 static struct dev_ops ptc_ops = {
 133         { "ptc", CDEV_MAJOR_C, D_TTY | D_KQFILTER | D_MASTER },
 134         .d_open =       ptcopen,
 135         .d_close =      ptcclose,
 136         .d_read =       ptcread,
 137         .d_write =      ptcwrite,
 138         .d_ioctl =      ptyioctl,
 139         .d_kqfilter =   ptckqfilter,
 140         .d_revoke =     ttyrevoke
 141 };
 142
 143 #define BUFSIZ 100              /* Chunk size iomoved to/from user */
 144
 145 struct  pt_ioctl {
 146         int     pt_flags;
 147         int     pt_flags2;
 148         struct  selinfo pt_selr, pt_selw;
 149         u_char  pt_send;
 150         u_char  pt_ucntl;
 151         struct tty pt_tty;
 152         cdev_t  devs, devc;
 153         struct  prison *pt_prison;
 154 };
 155
 156 #define PF_PKT          0x08            /* packet mode */
 157 #define PF_STOPPED      0x10            /* user told stopped */
 158 #define PF_REMOTE       0x20            /* remote and flow controlled input */
 159 #define PF_NOSTOP       0x40
 160 #define PF_UCNTL        0x80            /* user control mode */
 161
 162 #define PF_UNIX98       0x01
 163 #define PF_SOPEN        0x02
 164 #define PF_MOPEN        0x04
 165
 166 static int
 167 ptydebug(int level, char *fmt, ...)
 168 {
 169         __va_list ap;
 170
 171         __va_start(ap, fmt);
 172         if (level <= pty_debug_level)
 173                 kvprintf(fmt, ap);
 174         __va_end(ap);
 175
 176         return 0;
 177 }
 178
 179 /*
 180  * This function creates and initializes a pts/ptc pair
 181  *
 182  * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
 183  * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
 184  *
 185  * XXX: define and add mapping of upper minor bits to allow more
 186  *      than 256 ptys.
 187  */
 188 static void
 189 ptyinit(int n)
 190 {
 191         cdev_t devs, devc;
 192         char *names = "pqrsPQRS";
 193         struct pt_ioctl *pt;
 194
 195         /* For now we only map the lower 8 bits of the minor */
 196         if (n & ~0xff)
 197                 return;
 198
 199         pt = kmalloc(sizeof(*pt), M_PTY, M_WAITOK | M_ZERO);
 200         pt->devs = devs = make_dev(&pts_ops, n,
 201             0, 0, 0666, "tty%c%r", names[n / 32], n % 32);
 202         pt->devc = devc = make_dev(&ptc_ops, n,
 203             0, 0, 0666, "pty%c%r", names[n / 32], n % 32);
 204
 205         devs->si_drv1 = devc->si_drv1 = pt;
 206         devs->si_tty = devc->si_tty = &pt->pt_tty;
 207         devs->si_flags |= SI_OVERRIDE;  /* uid, gid, perms from dev */
 208         devc->si_flags |= SI_OVERRIDE;  /* uid, gid, perms from dev */
 209         pt->pt_tty.t_dev = devs;
 210         ttyregister(&pt->pt_tty);
 211 }
 212
 213 #ifdef UNIX98_PTYS
 214 static int
 215 ptyclone(struct dev_clone_args *ap)
 216 {
 217         int unit;
 218         struct pt_ioctl *pt;
 219
 220         /*
 221          * Limit the number of unix98 pty (slave) devices to 1000, as
 222          * the utmp(5) format only allows for 8 bytes for the tty,
 223          * "pts/XXX".
 224          * If this limit is reached, we don't clone and return error
 225          * to devfs.
 226          */
 227         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(pty), 1000);
 228
 229         if (unit < 0) {
 230                 ap->a_dev = NULL;
 231                 return 1;
 232         }
 233
 234         pt = kmalloc(sizeof(*pt), M_PTY, M_WAITOK | M_ZERO);
 235
 236         pt->devc = ap->a_dev = make_only_dev(&ptc98_ops, unit, ap->a_cred->cr_ruid,
 237             0, 0600, "ptm/%d", unit);
 238         pt->devs = make_dev(&pts98_ops, unit, ap->a_cred->cr_ruid, GID_TTY, 0620,
 239             "pts/%d", unit);
 240
 241         pt->devs->si_flags |= SI_OVERRIDE;      /* uid, gid, perms from dev */
 242         pt->devc->si_flags |= SI_OVERRIDE;      /* uid, gid, perms from dev */
 243
 244         pt->devs->si_drv1 = pt->devc->si_drv1 = pt;
 245         pt->devs->si_tty = pt->devc->si_tty = &pt->pt_tty;
 246         pt->pt_tty.t_dev = pt->devs;
 247         pt->pt_flags2 |= PF_UNIX98;
 248
 249         ttyregister(&pt->pt_tty);
 250
 251         return 0;
 252 }
 253 #endif
 254
 255 /*ARGSUSED*/
 256 static  int
 257 ptsopen(struct dev_open_args *ap)
 258 {
 259         cdev_t dev = ap->a_head.a_dev;
 260         struct tty *tp;
 261         int error;
 262         struct pt_ioctl *pti;
 263
 264         if (!dev->si_drv1)
 265                 ptyinit(minor(dev));
 266         if (!dev->si_drv1)
 267                 return(ENXIO);
 268         pti = dev->si_drv1;
 269         tp = dev->si_tty;
 270         if ((tp->t_state & TS_ISOPEN) == 0) {
 271                 ttychars(tp);           /* Set up default chars */
 272                 tp->t_iflag = TTYDEF_IFLAG;
 273                 tp->t_oflag = TTYDEF_OFLAG;
 274                 tp->t_lflag = TTYDEF_LFLAG;
 275                 tp->t_cflag = TTYDEF_CFLAG;
 276                 tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
 277         } else if ((tp->t_state & TS_XCLUDE) && priv_check_cred(ap->a_cred, PRIV_ROOT, 0)) {
 278                 return (EBUSY);
 279         } else if (pti->pt_prison != ap->a_cred->cr_prison) {
 280                 return (EBUSY);
 281         }
 282         if (tp->t_oproc)                        /* Ctrlr still around. */
 283                 (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 284         while ((tp->t_state & TS_CARR_ON) == 0) {
 285                 if (ap->a_oflags & FNONBLOCK)
 286                         break;
 287                 error = ttysleep(tp, TSA_CARR_ON(tp), PCATCH, "ptsopn", 0);
 288                 if (error)
 289                         return (error);
 290         }
 291         tp->t_state &= ~TS_ZOMBIE;
 292         error = (*linesw[tp->t_line].l_open)(dev, tp);
 293         if (error == 0)
 294                 ptcwakeup(tp, FREAD|FWRITE);
 295
 296 #ifdef UNIX98_PTYS
 297         /*
 298          * Unix98 pty stuff.
 299          * On open of the slave, we set the corresponding flag in the common
 300          * struct.
 301          */
 302         ptydebug(1, "ptsopen=%s | unix98? %s\n", dev->si_name,
 303             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 304
 305         if ((!error) && (pti->pt_flags2 & PF_UNIX98)) {
 306                 pti->pt_flags2 |= PF_SOPEN;
 307         }
 308 #endif
 309
 310         return (error);
 311 }
 312
 313 static  int
 314 ptsclose(struct dev_close_args *ap)
 315 {
 316         cdev_t dev = ap->a_head.a_dev;
 317         struct tty *tp;
 318         struct pt_ioctl *pti = dev->si_drv1;
 319         int err;
 320
 321         tp = dev->si_tty;
 322         err = (*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
 323         ptsstop(tp, FREAD|FWRITE);
 324         (void) ttyclose(tp); /* clears t_state */
 325         tp->t_state |= TS_ZOMBIE;
 326
 327 #ifdef UNIX98_PTYS
 328         /*
 329          * Unix98 pty stuff.
 330          * On close of the slave, we unset the corresponding flag, and if the master
 331          * isn't open anymore, we destroy the slave and unset the unit.
 332          */
 333         ptydebug(1, "ptsclose=%s | unix98? %s\n", dev->si_name,
 334             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 335
 336         if (pti->pt_flags2 & PF_UNIX98) {
 337                 pti->pt_flags2 &= ~PF_SOPEN;
 338                 KKASSERT((pti->pt_flags2 & PF_SOPEN) == 0);
 339                 ptydebug(1, "master open? %s\n",
 340                     (pti->pt_flags2 & PF_MOPEN)?"yes":"no");
 341
 342                 if (!(pti->pt_flags2 & PF_SOPEN) && !(pti->pt_flags2 & PF_MOPEN)) {
 343                         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(pty), dev->si_uminor);
 344                         destroy_dev(dev);
 345                 }
 346         }
 347 #endif
 348
 349         return (err);
 350 }
 351
 352 static  int
 353 ptsread(struct dev_read_args *ap)
 354 {
 355         cdev_t dev = ap->a_head.a_dev;
 356         struct proc *p = curproc;
 357         struct tty *tp = dev->si_tty;
 358         struct pt_ioctl *pti = dev->si_drv1;
 359         struct lwp *lp;
 360
 361         int error = 0;
 362
 363         lp = curthread->td_lwp;
 364
 365 again:
 366         if (pti->pt_flags & PF_REMOTE) {
 367                 while (isbackground(p, tp)) {
 368                         if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
 369                             SIGISMEMBER(lp->lwp_sigmask, SIGTTIN) ||
 370                             p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT)
 371                                 return (EIO);
 372                         pgsignal(p->p_pgrp, SIGTTIN, 1);
 373                         error = ttysleep(tp, &lbolt, PCATCH, "ptsbg", 0);
 374                         if (error)
 375                                 return (error);
 376                 }
 377                 if (tp->t_canq.c_cc == 0) {
 378                         if (ap->a_ioflag & IO_NDELAY)
 379                                 return (EWOULDBLOCK);
 380                         error = ttysleep(tp, TSA_PTS_READ(tp), PCATCH,
 381                                          "ptsin", 0);
 382                         if (error)
 383                                 return (error);
 384                         goto again;
 385                 }
 386                 while (tp->t_canq.c_cc > 1 && ap->a_uio->uio_resid > 0)
 387                         if (ureadc(clist_getc(&tp->t_canq), ap->a_uio) < 0) {
 388                                 error = EFAULT;
 389                                 break;
 390                         }
 391                 if (tp->t_canq.c_cc == 1)
 392                         clist_getc(&tp->t_canq);
 393                 if (tp->t_canq.c_cc)
 394                         return (error);
 395         } else
 396                 if (tp->t_oproc)
 397                         error = (*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag);
 398         ptcwakeup(tp, FWRITE);
 399         return (error);
 400 }
 401
 402 /*
 403  * Write to pseudo-tty.
 404  * Wakeups of controlling tty will happen
 405  * indirectly, when tty driver calls ptsstart.
 406  */
 407 static  int
 408 ptswrite(struct dev_write_args *ap)
 409 {
 410         cdev_t dev = ap->a_head.a_dev;
 411         struct tty *tp;
 412
 413         tp = dev->si_tty;
 414         if (tp->t_oproc == 0)
 415                 return (EIO);
 416         return ((*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag));
 417 }
 418
 419 /*
 420  * Start output on pseudo-tty.
 421  * Wake up process selecting or sleeping for input from controlling tty.
 422  */
 423 static void
 424 ptsstart(struct tty *tp)
 425 {
 426         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 427
 428         if (tp->t_state & TS_TTSTOP)
 429                 return;
 430         if (pti->pt_flags & PF_STOPPED) {
 431                 pti->pt_flags &= ~PF_STOPPED;
 432                 pti->pt_send = TIOCPKT_START;
 433         }
 434         ptcwakeup(tp, FREAD);
 435 }
 436
 437 static void
 438 ptcwakeup(struct tty *tp, int flag)
 439 {
 440         if (flag & FREAD) {
 441                 wakeup(TSA_PTC_READ(tp));
 442                 KNOTE(&tp->t_rsel.si_note, 0);
 443         }
 444         if (flag & FWRITE) {
 445                 wakeup(TSA_PTC_WRITE(tp));
 446                 KNOTE(&tp->t_wsel.si_note, 0);
 447         }
 448 }
 449
 450 static  int
 451 ptcopen(struct dev_open_args *ap)
 452 {
 453         cdev_t dev = ap->a_head.a_dev;
 454         struct tty *tp;
 455         struct pt_ioctl *pti;
 456
 457         if (!dev->si_drv1)
 458                 ptyinit(minor(dev));
 459         if (!dev->si_drv1)
 460                 return(ENXIO);
 461         pti = dev->si_drv1;
 462         if (pti->pt_prison && pti->pt_prison != ap->a_cred->cr_prison)
 463                 return(EBUSY);
 464         tp = dev->si_tty;
 465         if (tp->t_oproc)
 466                 return (EIO);
 467         tp->t_oproc = ptsstart;
 468         tp->t_stop = ptsstop;
 469         (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 470         tp->t_lflag &= ~EXTPROC;
 471         pti->pt_prison = ap->a_cred->cr_prison;
 472         pti->pt_flags = 0;
 473         pti->pt_send = 0;
 474         pti->pt_ucntl = 0;
 475
 476         pti->devs->si_uid = ap->a_cred->cr_uid;
 477         pti->devs->si_gid = 0;
 478         pti->devs->si_perms = 0600;
 479         pti->devc->si_uid = ap->a_cred->cr_uid;
 480         pti->devc->si_gid = 0;
 481         pti->devc->si_perms = 0600;
 482
 483 #ifdef UNIX98_PTYS
 484         /*
 485          * Unix98 pty stuff.
 486          * On open of the master, we set the corresponding flag in the common
 487          * struct.
 488          */
 489         ptydebug(1, "ptcopen=%s (master) | unix98? %s\n", dev->si_name,
 490             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 491
 492         if (pti->pt_flags2 & PF_UNIX98) {
 493                 pti->pt_flags2 |= PF_MOPEN;
 494         }
 495 #endif
 496
 497         return (0);
 498 }
 499
 500 static  int
 501 ptcclose(struct dev_close_args *ap)
 502 {
 503         cdev_t dev = ap->a_head.a_dev;
 504         struct tty *tp;
 505         struct pt_ioctl *pti = dev->si_drv1;
 506
 507         tp = dev->si_tty;
 508         (void)(*linesw[tp->t_line].l_modem)(tp, 0);
 509
 510 #ifdef UNIX98_PTYS
 511         /*
 512          * Unix98 pty stuff.
 513          * On close of the master, we unset the corresponding flag in the common
 514          * struct asap.
 515          */
 516         pti->pt_flags2 &= ~PF_MOPEN;
 517 #endif
 518
 519         /*
 520          * XXX MDMBUF makes no sense for ptys but would inhibit the above
 521          * l_modem().  CLOCAL makes sense but isn't supported.   Special
 522          * l_modem()s that ignore carrier drop make no sense for ptys but
 523          * may be in use because other parts of the line discipline make
 524          * sense for ptys.  Recover by doing everything that a normal
 525          * ttymodem() would have done except for sending a SIGHUP.
 526          */
 527         if (tp->t_state & TS_ISOPEN) {
 528                 tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
 529                 tp->t_state |= TS_ZOMBIE;
 530                 ttyflush(tp, FREAD | FWRITE);
 531         }
 532         tp->t_oproc = 0;                /* mark closed */
 533
 534         pti = dev->si_drv1;
 535         pti->pt_prison = NULL;
 536         pti->devs->si_uid = 0;
 537         pti->devs->si_gid = 0;
 538         pti->devs->si_perms = 0666;
 539         pti->devc->si_uid = 0;
 540         pti->devc->si_gid = 0;
 541         pti->devc->si_perms = 0666;
 542
 543 #ifdef UNIX98_PTYS
 544         /*
 545          * Unix98 pty stuff.
 546          * On close of the master, we destroy the master and, if no slaves are open,
 547          * we destroy the slave device and unset the unit.
 548          */
 549         ptydebug(1, "ptcclose=%s (master) | unix98? %s\n", dev->si_name,
 550             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 551         if (pti->pt_flags2 & PF_UNIX98) {
 552                 KKASSERT((pti->pt_flags2 & PF_MOPEN) == 0);
 553                 destroy_dev(dev);
 554                 pti->devc = NULL;
 555
 556                 if (!(pti->pt_flags2 & PF_SOPEN)) {
 557                         ptydebug(1, "ptcclose: slaves are not open\n");
 558                         destroy_dev(pti->devs);
 559                         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(pty), dev->si_uminor);
 560                 }
 561         }
 562 #endif
 563
 564         return (0);
 565 }
 566
 567 static  int
 568 ptcread(struct dev_read_args *ap)
 569 {
 570         cdev_t dev = ap->a_head.a_dev;
 571         struct tty *tp = dev->si_tty;
 572         struct pt_ioctl *pti = dev->si_drv1;
 573         char buf[BUFSIZ];
 574         int error = 0, cc;
 575
 576         /*
 577          * We want to block until the slave
 578          * is open, and there's something to read;
 579          * but if we lost the slave or we're NBIO,
 580          * then return the appropriate error instead.
 581          */
 582         for (;;) {
 583                 if (tp->t_state&TS_ISOPEN) {
 584                         if (pti->pt_flags&PF_PKT && pti->pt_send) {
 585                                 error = ureadc((int)pti->pt_send, ap->a_uio);
 586                                 if (error)
 587                                         return (error);
 588                                 if (pti->pt_send & TIOCPKT_IOCTL) {
 589                                         cc = (int)szmin(ap->a_uio->uio_resid,
 590                                                         sizeof(tp->t_termios));
 591                                         uiomove((caddr_t)&tp->t_termios, cc,
 592                                                 ap->a_uio);
 593                                 }
 594                                 pti->pt_send = 0;
 595                                 return (0);
 596                         }
 597                         if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
 598                                 error = ureadc((int)pti->pt_ucntl, ap->a_uio);
 599                                 if (error)
 600                                         return (error);
 601                                 pti->pt_ucntl = 0;
 602                                 return (0);
 603                         }
 604                         if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
 605                                 break;
 606                 }
 607                 if ((tp->t_state & TS_CONNECTED) == 0)
 608                         return (0);     /* EOF */
 609                 if (ap->a_ioflag & IO_NDELAY)
 610                         return (EWOULDBLOCK);
 611                 error = tsleep(TSA_PTC_READ(tp), PCATCH, "ptcin", 0);
 612                 if (error)
 613                         return (error);
 614         }
 615         if (pti->pt_flags & (PF_PKT|PF_UCNTL))
 616                 error = ureadc(0, ap->a_uio);
 617         while (ap->a_uio->uio_resid > 0 && error == 0) {
 618                 cc = q_to_b(&tp->t_outq, buf,
 619                             (int)szmin(ap->a_uio->uio_resid, BUFSIZ));
 620                 if (cc <= 0)
 621                         break;
 622                 error = uiomove(buf, (size_t)cc, ap->a_uio);
 623         }
 624         ttwwakeup(tp);
 625         return (error);
 626 }
 627
 628 static  void
 629 ptsstop(struct tty *tp, int flush)
 630 {
 631         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 632         int flag;
 633
 634         /* note: FLUSHREAD and FLUSHWRITE already ok */
 635         if (flush == 0) {
 636                 flush = TIOCPKT_STOP;
 637                 pti->pt_flags |= PF_STOPPED;
 638         } else
 639                 pti->pt_flags &= ~PF_STOPPED;
 640         pti->pt_send |= flush;
 641         /* change of perspective */
 642         flag = 0;
 643         if (flush & FREAD)
 644                 flag |= FWRITE;
 645         if (flush & FWRITE)
 646                 flag |= FREAD;
 647         ptcwakeup(tp, flag);
 648 }
 649
 650 /*
 651  * kqueue ops for pseudo-terminals.
 652  */
 653 static struct filterops ptcread_filtops =
 654         { 1, NULL, filt_ptcrdetach, filt_ptcread };
 655 static struct filterops ptcwrite_filtops =
 656         { 1, NULL, filt_ptcwdetach, filt_ptcwrite };
 657
 658 static  int
 659 ptckqfilter(struct dev_kqfilter_args *ap)
 660 {
 661         cdev_t dev = ap->a_head.a_dev;
 662         struct knote *kn = ap->a_kn;
 663         struct tty *tp = dev->si_tty;
 664         struct klist *klist;
 665
 666         ap->a_result = 0;
 667         switch (kn->kn_filter) {
 668         case EVFILT_READ:
 669                 klist = &tp->t_rsel.si_note;
 670                 kn->kn_fop = &ptcread_filtops;
 671                 break;
 672         case EVFILT_WRITE:
 673                 klist = &tp->t_wsel.si_note;
 674                 kn->kn_fop = &ptcwrite_filtops;
 675                 break;
 676         default:
 677                 ap->a_result = EOPNOTSUPP;
 678                 return (0);
 679         }
 680
 681         kn->kn_hook = (caddr_t)dev;
 682
 683         crit_enter();
 684         SLIST_INSERT_HEAD(klist, kn, kn_selnext);
 685         crit_exit();
 686
 687         return (0);
 688 }
 689
 690 static int
 691 filt_ptcread (struct knote *kn, long hint)
 692 {
 693         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 694         struct pt_ioctl *pti = ((cdev_t)kn->kn_hook)->si_drv1;
 695
 696         if (tp->t_state & TS_ZOMBIE) {
 697                 kn->kn_flags |= EV_EOF;
 698                 return (1);
 699         }
 700
 701         if ((tp->t_state & TS_ISOPEN) &&
 702             ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
 703              ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
 704              ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))) {
 705                 kn->kn_data = tp->t_outq.c_cc;
 706                 return(1);
 707         } else {
 708                 return(0);
 709         }
 710 }
 711
 712 static int
 713 filt_ptcwrite (struct knote *kn, long hint)
 714 {
 715         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 716         struct pt_ioctl *pti = ((cdev_t)kn->kn_hook)->si_drv1;
 717
 718         if (tp->t_state & TS_ZOMBIE) {
 719                 kn->kn_flags |= EV_EOF;
 720                 return (1);
 721         }
 722
 723         if (tp->t_state & TS_ISOPEN &&
 724             ((pti->pt_flags & PF_REMOTE) ?
 725              (tp->t_canq.c_cc == 0) :
 726              ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
 727               (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON))))) {
 728                 kn->kn_data = tp->t_canq.c_cc + tp->t_rawq.c_cc;
 729                 return(1);
 730         } else {
 731                 return(0);
 732         }
 733 }
 734
 735 static void
 736 filt_ptcrdetach (struct knote *kn)
 737 {
 738         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 739
 740         crit_enter();
 741         SLIST_REMOVE(&tp->t_rsel.si_note, kn, knote, kn_selnext);
 742         crit_exit();
 743 }
 744
 745 static void
 746 filt_ptcwdetach (struct knote *kn)
 747 {
 748         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 749
 750         crit_enter();
 751         SLIST_REMOVE(&tp->t_wsel.si_note, kn, knote, kn_selnext);
 752         crit_exit();
 753 }
 754
 755 /*
 756  * I/O ops
 757  */
 758 static  int
 759 ptcwrite(struct dev_write_args *ap)
 760 {
 761         cdev_t dev = ap->a_head.a_dev;
 762         struct tty *tp = dev->si_tty;
 763         u_char *cp = 0;
 764         int cc = 0;
 765         u_char locbuf[BUFSIZ];
 766         int cnt = 0;
 767         struct pt_ioctl *pti = dev->si_drv1;
 768         int error = 0;
 769
 770 again:
 771         if ((tp->t_state&TS_ISOPEN) == 0)
 772                 goto block;
 773         if (pti->pt_flags & PF_REMOTE) {
 774                 if (tp->t_canq.c_cc)
 775                         goto block;
 776                 while ((ap->a_uio->uio_resid > 0 || cc > 0) &&
 777                        tp->t_canq.c_cc < TTYHOG - 1) {
 778                         if (cc == 0) {
 779                                 cc = (int)szmin(ap->a_uio->uio_resid, BUFSIZ);
 780                                 cc = imin(cc, TTYHOG - 1 - tp->t_canq.c_cc);
 781                                 cp = locbuf;
 782                                 error = uiomove(cp, (size_t)cc, ap->a_uio);
 783                                 if (error)
 784                                         return (error);
 785                                 /* check again for safety */
 786                                 if ((tp->t_state & TS_ISOPEN) == 0) {
 787                                         /* adjust as usual */
 788                                         ap->a_uio->uio_resid += cc;
 789                                         return (EIO);
 790                                 }
 791                         }
 792                         if (cc > 0) {
 793                                 cc = b_to_q((char *)cp, cc, &tp->t_canq);
 794                                 /*
 795                                  * XXX we don't guarantee that the canq size
 796                                  * is >= TTYHOG, so the above b_to_q() may
 797                                  * leave some bytes uncopied.  However, space
 798                                  * is guaranteed for the null terminator if
 799                                  * we don't fail here since (TTYHOG - 1) is
 800                                  * not a multiple of CBSIZE.
 801                                  */
 802                                 if (cc > 0)
 803                                         break;
 804                         }
 805                 }
 806                 /* adjust for data copied in but not written */
 807                 ap->a_uio->uio_resid += cc;
 808                 clist_putc(0, &tp->t_canq);
 809                 ttwakeup(tp);
 810                 wakeup(TSA_PTS_READ(tp));
 811                 return (0);
 812         }
 813         while (ap->a_uio->uio_resid > 0 || cc > 0) {
 814                 if (cc == 0) {
 815                         cc = (int)szmin(ap->a_uio->uio_resid, BUFSIZ);
 816                         cp = locbuf;
 817                         error = uiomove(cp, (size_t)cc, ap->a_uio);
 818                         if (error)
 819                                 return (error);
 820                         /* check again for safety */
 821                         if ((tp->t_state & TS_ISOPEN) == 0) {
 822                                 /* adjust for data copied in but not written */
 823                                 ap->a_uio->uio_resid += cc;
 824                                 return (EIO);
 825                         }
 826                 }
 827                 while (cc > 0) {
 828                         if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
 829                            (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
 830                                 wakeup(TSA_HUP_OR_INPUT(tp));
 831                                 goto block;
 832                         }
 833                         (*linesw[tp->t_line].l_rint)(*cp++, tp);
 834                         cnt++;
 835                         cc--;
 836                 }
 837                 cc = 0;
 838         }
 839         return (0);
 840 block:
 841         /*
 842          * Come here to wait for slave to open, for space
 843          * in outq, or space in rawq, or an empty canq.
 844          */
 845         if ((tp->t_state & TS_CONNECTED) == 0) {
 846                 /* adjust for data copied in but not written */
 847                 ap->a_uio->uio_resid += cc;
 848                 return (EIO);
 849         }
 850         if (ap->a_ioflag & IO_NDELAY) {
 851                 /* adjust for data copied in but not written */
 852                 ap->a_uio->uio_resid += cc;
 853                 if (cnt == 0)
 854                         return (EWOULDBLOCK);
 855                 return (0);
 856         }
 857         error = tsleep(TSA_PTC_WRITE(tp), PCATCH, "ptcout", 0);
 858         if (error) {
 859                 /* adjust for data copied in but not written */
 860                 ap->a_uio->uio_resid += cc;
 861                 return (error);
 862         }
 863         goto again;
 864 }
 865
 866 /*ARGSUSED*/
 867 static  int
 868 ptyioctl(struct dev_ioctl_args *ap)
 869 {
 870         cdev_t dev = ap->a_head.a_dev;
 871         struct tty *tp = dev->si_tty;
 872         struct pt_ioctl *pti = dev->si_drv1;
 873         u_char *cc = tp->t_cc;
 874         int stop, error;
 875
 876         if (dev_dflags(dev) & D_MASTER) {
 877                 switch (ap->a_cmd) {
 878
 879                 case TIOCGPGRP:
 880                         /*
 881                          * We avoid calling ttioctl on the controller since,
 882                          * in that case, tp must be the controlling terminal.
 883                          */
 884                         *(int *)ap->a_data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
 885                         return (0);
 886
 887                 case TIOCPKT:
 888                         if (*(int *)ap->a_data) {
 889                                 if (pti->pt_flags & PF_UCNTL)
 890                                         return (EINVAL);
 891                                 pti->pt_flags |= PF_PKT;
 892                         } else
 893                                 pti->pt_flags &= ~PF_PKT;
 894                         return (0);
 895
 896                 case TIOCUCNTL:
 897                         if (*(int *)ap->a_data) {
 898                                 if (pti->pt_flags & PF_PKT)
 899                                         return (EINVAL);
 900                                 pti->pt_flags |= PF_UCNTL;
 901                         } else
 902                                 pti->pt_flags &= ~PF_UCNTL;
 903                         return (0);
 904
 905                 case TIOCREMOTE:
 906                         if (*(int *)ap->a_data)
 907                                 pti->pt_flags |= PF_REMOTE;
 908                         else
 909                                 pti->pt_flags &= ~PF_REMOTE;
 910                         ttyflush(tp, FREAD|FWRITE);
 911                         return (0);
 912
 913                 case TIOCISPTMASTER:
 914                         if ((pti->pt_flags2 & PF_UNIX98) && (pti->devc == dev))
 915                                 return (0);
 916                         else
 917                                 return (EINVAL);
 918                 }
 919
 920                 /*
 921                  * The rest of the ioctls shouldn't be called until
 922                  * the slave is open.
 923                  */
 924                 if ((tp->t_state & TS_ISOPEN) == 0)
 925                         return (EAGAIN);
 926
 927                 switch (ap->a_cmd) {
 928 #ifdef COMPAT_43
 929                 case TIOCSETP:
 930                 case TIOCSETN:
 931 #endif
 932                 case TIOCSETD:
 933                 case TIOCSETA:
 934                 case TIOCSETAW:
 935                 case TIOCSETAF:
 936                         /*
 937                          * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
 938                          * ttywflush(tp) will hang if there are characters in
 939                          * the outq.
 940                          */
 941                         ndflush(&tp->t_outq, tp->t_outq.c_cc);
 942                         break;
 943
 944                 case TIOCSIG:
 945                         if (*(unsigned int *)ap->a_data >= NSIG ||
 946                             *(unsigned int *)ap->a_data == 0)
 947                                 return(EINVAL);
 948                         if ((tp->t_lflag&NOFLSH) == 0)
 949                                 ttyflush(tp, FREAD|FWRITE);
 950                         pgsignal(tp->t_pgrp, *(unsigned int *)ap->a_data, 1);
 951                         if ((*(unsigned int *)ap->a_data == SIGINFO) &&
 952                             ((tp->t_lflag&NOKERNINFO) == 0))
 953                                 ttyinfo(tp);
 954                         return(0);
 955                 }
 956         }
 957         if (ap->a_cmd == TIOCEXT) {
 958                 /*
 959                  * When the EXTPROC bit is being toggled, we need
 960                  * to send an TIOCPKT_IOCTL if the packet driver
 961                  * is turned on.
 962                  */
 963                 if (*(int *)ap->a_data) {
 964                         if (pti->pt_flags & PF_PKT) {
 965                                 pti->pt_send |= TIOCPKT_IOCTL;
 966                                 ptcwakeup(tp, FREAD);
 967                         }
 968                         tp->t_lflag |= EXTPROC;
 969                 } else {
 970                         if ((tp->t_lflag & EXTPROC) &&
 971                             (pti->pt_flags & PF_PKT)) {
 972                                 pti->pt_send |= TIOCPKT_IOCTL;
 973                                 ptcwakeup(tp, FREAD);
 974                         }
 975                         tp->t_lflag &= ~EXTPROC;
 976                 }
 977                 return(0);
 978         }
 979         error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data,
 980                                               ap->a_fflag, ap->a_cred);
 981         if (error == ENOIOCTL)
 982                  error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
 983         if (error == ENOIOCTL) {
 984                 if (pti->pt_flags & PF_UCNTL &&
 985                     (ap->a_cmd & ~0xff) == UIOCCMD(0)) {
 986                         if (ap->a_cmd & 0xff) {
 987                                 pti->pt_ucntl = (u_char)ap->a_cmd;
 988                                 ptcwakeup(tp, FREAD);
 989                         }
 990                         return (0);
 991                 }
 992                 error = ENOTTY;
 993         }
 994         /*
 995          * If external processing and packet mode send ioctl packet.
 996          */
 997         if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
 998                 switch(ap->a_cmd) {
 999                 case TIOCSETA:
1000                 case TIOCSETAW:
1001                 case TIOCSETAF:
1002 #ifdef COMPAT_43
1003                 case TIOCSETP:
1004                 case TIOCSETN:
1005 #endif
1006 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
1007                 case TIOCSETC:
1008                 case TIOCSLTC:
1009                 case TIOCLBIS:
1010                 case TIOCLBIC:
1011                 case TIOCLSET:
1012 #endif
1013                         pti->pt_send |= TIOCPKT_IOCTL;
1014                         ptcwakeup(tp, FREAD);
1015                 default:
1016                         break;
1017                 }
1018         }
1019         stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
1020                 && CCEQ(cc[VSTART], CTRL('q'));
1021         if (pti->pt_flags & PF_NOSTOP) {
1022                 if (stop) {
1023                         pti->pt_send &= ~TIOCPKT_NOSTOP;
1024                         pti->pt_send |= TIOCPKT_DOSTOP;
1025                         pti->pt_flags &= ~PF_NOSTOP;
1026                         ptcwakeup(tp, FREAD);
1027                 }
1028         } else {
1029                 if (!stop) {
1030                         pti->pt_send &= ~TIOCPKT_DOSTOP;
1031                         pti->pt_send |= TIOCPKT_NOSTOP;
1032                         pti->pt_flags |= PF_NOSTOP;
1033                         ptcwakeup(tp, FREAD);
1034                 }
1035         }
1036         return (error);
1037 }
1038
1039
1040 static void ptc_drvinit (void *unused);
1041
1042 #ifdef UNIX98_PTYS
1043 SYSCTL_INT(_kern, OID_AUTO, pty_debug, CTLFLAG_RW, &pty_debug_level,
1044                 0, "Change pty debug level");
1045 #endif
1046
1047 static void
1048 ptc_drvinit(void *unused)
1049 {
1050         int i;
1051
1052 #ifdef UNIX98_PTYS
1053         /*
1054          * Unix98 pty stuff.
1055          * Create the clonable base device.
1056          */
1057         make_autoclone_dev(&ptc_ops, &DEVFS_CLONE_BITMAP(pty), ptyclone,
1058             0, 0, 0666, "ptmx");
1059 #endif
1060
1061         for (i = 0; i < 256; i++) {
1062                 ptyinit(i);
1063         }
1064 }
1065
1066 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)