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         error = (*linesw[tp->t_line].l_open)(dev, tp);
 292         if (error == 0)
 293                 ptcwakeup(tp, FREAD|FWRITE);
 294
 295 #ifdef UNIX98_PTYS
 296         /*
 297          * Unix98 pty stuff.
 298          * On open of the slave, we set the corresponding flag in the common
 299          * struct.
 300          */
 301         ptydebug(1, "ptsopen=%s | unix98? %s\n", dev->si_name,
 302             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 303
 304         if ((!error) && (pti->pt_flags2 & PF_UNIX98)) {
 305                 pti->pt_flags2 |= PF_SOPEN;
 306         }
 307 #endif
 308
 309         return (error);
 310 }
 311
 312 static  int
 313 ptsclose(struct dev_close_args *ap)
 314 {
 315         cdev_t dev = ap->a_head.a_dev;
 316         struct tty *tp;
 317         struct pt_ioctl *pti = dev->si_drv1;
 318         int err;
 319
 320         tp = dev->si_tty;
 321         err = (*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
 322         ptsstop(tp, FREAD|FWRITE);
 323         (void) ttyclose(tp); /* clears t_state */
 324         tp->t_state |= TS_ZOMBIE;
 325
 326 #ifdef UNIX98_PTYS
 327         /*
 328          * Unix98 pty stuff.
 329          * On close of the slave, we unset the corresponding flag, and if the master
 330          * isn't open anymore, we destroy the slave and unset the unit.
 331          */
 332         ptydebug(1, "ptsclose=%s | unix98? %s\n", dev->si_name,
 333             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 334
 335         if (pti->pt_flags2 & PF_UNIX98) {
 336                 pti->pt_flags2 &= ~PF_SOPEN;
 337                 KKASSERT((pti->pt_flags2 & PF_SOPEN) == 0);
 338                 ptydebug(1, "master open? %s\n",
 339                     (pti->pt_flags2 & PF_MOPEN)?"yes":"no");
 340
 341                 if (!(pti->pt_flags2 & PF_SOPEN) && !(pti->pt_flags2 & PF_MOPEN)) {
 342                         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(pty), dev->si_uminor);
 343                         destroy_dev(dev);
 344                 }
 345         }
 346 #endif
 347
 348         return (err);
 349 }
 350
 351 static  int
 352 ptsread(struct dev_read_args *ap)
 353 {
 354         cdev_t dev = ap->a_head.a_dev;
 355         struct proc *p = curproc;
 356         struct tty *tp = dev->si_tty;
 357         struct pt_ioctl *pti = dev->si_drv1;
 358         struct lwp *lp;
 359
 360         int error = 0;
 361
 362         lp = curthread->td_lwp;
 363
 364 again:
 365         if (pti->pt_flags & PF_REMOTE) {
 366                 while (isbackground(p, tp)) {
 367                         if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
 368                             SIGISMEMBER(lp->lwp_sigmask, SIGTTIN) ||
 369                             p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT)
 370                                 return (EIO);
 371                         pgsignal(p->p_pgrp, SIGTTIN, 1);
 372                         error = ttysleep(tp, &lbolt, PCATCH, "ptsbg", 0);
 373                         if (error)
 374                                 return (error);
 375                 }
 376                 if (tp->t_canq.c_cc == 0) {
 377                         if (ap->a_ioflag & IO_NDELAY)
 378                                 return (EWOULDBLOCK);
 379                         error = ttysleep(tp, TSA_PTS_READ(tp), PCATCH,
 380                                          "ptsin", 0);
 381                         if (error)
 382                                 return (error);
 383                         goto again;
 384                 }
 385                 while (tp->t_canq.c_cc > 1 && ap->a_uio->uio_resid > 0)
 386                         if (ureadc(clist_getc(&tp->t_canq), ap->a_uio) < 0) {
 387                                 error = EFAULT;
 388                                 break;
 389                         }
 390                 if (tp->t_canq.c_cc == 1)
 391                         clist_getc(&tp->t_canq);
 392                 if (tp->t_canq.c_cc)
 393                         return (error);
 394         } else
 395                 if (tp->t_oproc)
 396                         error = (*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag);
 397         ptcwakeup(tp, FWRITE);
 398         return (error);
 399 }
 400
 401 /*
 402  * Write to pseudo-tty.
 403  * Wakeups of controlling tty will happen
 404  * indirectly, when tty driver calls ptsstart.
 405  */
 406 static  int
 407 ptswrite(struct dev_write_args *ap)
 408 {
 409         cdev_t dev = ap->a_head.a_dev;
 410         struct tty *tp;
 411
 412         tp = dev->si_tty;
 413         if (tp->t_oproc == 0)
 414                 return (EIO);
 415         return ((*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag));
 416 }
 417
 418 /*
 419  * Start output on pseudo-tty.
 420  * Wake up process selecting or sleeping for input from controlling tty.
 421  */
 422 static void
 423 ptsstart(struct tty *tp)
 424 {
 425         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 426
 427         if (tp->t_state & TS_TTSTOP)
 428                 return;
 429         if (pti->pt_flags & PF_STOPPED) {
 430                 pti->pt_flags &= ~PF_STOPPED;
 431                 pti->pt_send = TIOCPKT_START;
 432         }
 433         ptcwakeup(tp, FREAD);
 434 }
 435
 436 static void
 437 ptcwakeup(struct tty *tp, int flag)
 438 {
 439         if (flag & FREAD) {
 440                 wakeup(TSA_PTC_READ(tp));
 441                 KNOTE(&tp->t_rsel.si_note, 0);
 442         }
 443         if (flag & FWRITE) {
 444                 wakeup(TSA_PTC_WRITE(tp));
 445                 KNOTE(&tp->t_wsel.si_note, 0);
 446         }
 447 }
 448
 449 static  int
 450 ptcopen(struct dev_open_args *ap)
 451 {
 452         cdev_t dev = ap->a_head.a_dev;
 453         struct tty *tp;
 454         struct pt_ioctl *pti;
 455
 456         if (!dev->si_drv1)
 457                 ptyinit(minor(dev));
 458         if (!dev->si_drv1)
 459                 return(ENXIO);
 460         pti = dev->si_drv1;
 461         if (pti->pt_prison && pti->pt_prison != ap->a_cred->cr_prison)
 462                 return(EBUSY);
 463         tp = dev->si_tty;
 464         if (tp->t_oproc)
 465                 return (EIO);
 466         tp->t_oproc = ptsstart;
 467         tp->t_stop = ptsstop;
 468         (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 469         tp->t_lflag &= ~EXTPROC;
 470         pti->pt_prison = ap->a_cred->cr_prison;
 471         pti->pt_flags = 0;
 472         pti->pt_send = 0;
 473         pti->pt_ucntl = 0;
 474
 475         pti->devs->si_uid = ap->a_cred->cr_uid;
 476         pti->devs->si_gid = 0;
 477         pti->devs->si_perms = 0600;
 478         pti->devc->si_uid = ap->a_cred->cr_uid;
 479         pti->devc->si_gid = 0;
 480         pti->devc->si_perms = 0600;
 481
 482 #ifdef UNIX98_PTYS
 483         /*
 484          * Unix98 pty stuff.
 485          * On open of the master, we set the corresponding flag in the common
 486          * struct.
 487          */
 488         ptydebug(1, "ptcopen=%s (master) | unix98? %s\n", dev->si_name,
 489             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 490
 491         if (pti->pt_flags2 & PF_UNIX98) {
 492                 pti->pt_flags2 |= PF_MOPEN;
 493         }
 494 #endif
 495
 496         return (0);
 497 }
 498
 499 static  int
 500 ptcclose(struct dev_close_args *ap)
 501 {
 502         cdev_t dev = ap->a_head.a_dev;
 503         struct tty *tp;
 504         struct pt_ioctl *pti = dev->si_drv1;
 505
 506         tp = dev->si_tty;
 507         (void)(*linesw[tp->t_line].l_modem)(tp, 0);
 508
 509 #ifdef UNIX98_PTYS
 510         /*
 511          * Unix98 pty stuff.
 512          * On close of the master, we unset the corresponding flag in the common
 513          * struct asap.
 514          */
 515         pti->pt_flags2 &= ~PF_MOPEN;
 516 #endif
 517
 518         /*
 519          * XXX MDMBUF makes no sense for ptys but would inhibit the above
 520          * l_modem().  CLOCAL makes sense but isn't supported.   Special
 521          * l_modem()s that ignore carrier drop make no sense for ptys but
 522          * may be in use because other parts of the line discipline make
 523          * sense for ptys.  Recover by doing everything that a normal
 524          * ttymodem() would have done except for sending a SIGHUP.
 525          */
 526         if (tp->t_state & TS_ISOPEN) {
 527                 tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
 528                 tp->t_state |= TS_ZOMBIE;
 529                 ttyflush(tp, FREAD | FWRITE);
 530         }
 531         tp->t_oproc = 0;                /* mark closed */
 532
 533         pti = dev->si_drv1;
 534         pti->pt_prison = NULL;
 535         pti->devs->si_uid = 0;
 536         pti->devs->si_gid = 0;
 537         pti->devs->si_perms = 0666;
 538         pti->devc->si_uid = 0;
 539         pti->devc->si_gid = 0;
 540         pti->devc->si_perms = 0666;
 541
 542 #ifdef UNIX98_PTYS
 543         /*
 544          * Unix98 pty stuff.
 545          * On close of the master, we destroy the master and, if no slaves are open,
 546          * we destroy the slave device and unset the unit.
 547          */
 548         ptydebug(1, "ptcclose=%s (master) | unix98? %s\n", dev->si_name,
 549             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 550         if (pti->pt_flags2 & PF_UNIX98) {
 551                 KKASSERT((pti->pt_flags2 & PF_MOPEN) == 0);
 552                 destroy_dev(dev);
 553                 pti->devc = NULL;
 554
 555                 if (!(pti->pt_flags2 & PF_SOPEN)) {
 556                         ptydebug(1, "ptcclose: slaves are not open\n");
 557                         destroy_dev(pti->devs);
 558                         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(pty), dev->si_uminor);
 559                 }
 560         }
 561 #endif
 562
 563         return (0);
 564 }
 565
 566 static  int
 567 ptcread(struct dev_read_args *ap)
 568 {
 569         cdev_t dev = ap->a_head.a_dev;
 570         struct tty *tp = dev->si_tty;
 571         struct pt_ioctl *pti = dev->si_drv1;
 572         char buf[BUFSIZ];
 573         int error = 0, cc;
 574
 575         /*
 576          * We want to block until the slave
 577          * is open, and there's something to read;
 578          * but if we lost the slave or we're NBIO,
 579          * then return the appropriate error instead.
 580          */
 581         for (;;) {
 582                 if (tp->t_state&TS_ISOPEN) {
 583                         if (pti->pt_flags&PF_PKT && pti->pt_send) {
 584                                 error = ureadc((int)pti->pt_send, ap->a_uio);
 585                                 if (error)
 586                                         return (error);
 587                                 if (pti->pt_send & TIOCPKT_IOCTL) {
 588                                         cc = (int)szmin(ap->a_uio->uio_resid,
 589                                                         sizeof(tp->t_termios));
 590                                         uiomove((caddr_t)&tp->t_termios, cc,
 591                                                 ap->a_uio);
 592                                 }
 593                                 pti->pt_send = 0;
 594                                 return (0);
 595                         }
 596                         if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
 597                                 error = ureadc((int)pti->pt_ucntl, ap->a_uio);
 598                                 if (error)
 599                                         return (error);
 600                                 pti->pt_ucntl = 0;
 601                                 return (0);
 602                         }
 603                         if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
 604                                 break;
 605                 }
 606                 if ((tp->t_state & TS_CONNECTED) == 0)
 607                         return (0);     /* EOF */
 608                 if (ap->a_ioflag & IO_NDELAY)
 609                         return (EWOULDBLOCK);
 610                 error = tsleep(TSA_PTC_READ(tp), PCATCH, "ptcin", 0);
 611                 if (error)
 612                         return (error);
 613         }
 614         if (pti->pt_flags & (PF_PKT|PF_UCNTL))
 615                 error = ureadc(0, ap->a_uio);
 616         while (ap->a_uio->uio_resid > 0 && error == 0) {
 617                 cc = q_to_b(&tp->t_outq, buf,
 618                             (int)szmin(ap->a_uio->uio_resid, BUFSIZ));
 619                 if (cc <= 0)
 620                         break;
 621                 error = uiomove(buf, (size_t)cc, ap->a_uio);
 622         }
 623         ttwwakeup(tp);
 624         return (error);
 625 }
 626
 627 static  void
 628 ptsstop(struct tty *tp, int flush)
 629 {
 630         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 631         int flag;
 632
 633         /* note: FLUSHREAD and FLUSHWRITE already ok */
 634         if (flush == 0) {
 635                 flush = TIOCPKT_STOP;
 636                 pti->pt_flags |= PF_STOPPED;
 637         } else
 638                 pti->pt_flags &= ~PF_STOPPED;
 639         pti->pt_send |= flush;
 640         /* change of perspective */
 641         flag = 0;
 642         if (flush & FREAD)
 643                 flag |= FWRITE;
 644         if (flush & FWRITE)
 645                 flag |= FREAD;
 646         ptcwakeup(tp, flag);
 647 }
 648
 649 /*
 650  * kqueue ops for pseudo-terminals.
 651  */
 652 static struct filterops ptcread_filtops =
 653         { 1, NULL, filt_ptcrdetach, filt_ptcread };
 654 static struct filterops ptcwrite_filtops =
 655         { 1, NULL, filt_ptcwdetach, filt_ptcwrite };
 656
 657 static  int
 658 ptckqfilter(struct dev_kqfilter_args *ap)
 659 {
 660         cdev_t dev = ap->a_head.a_dev;
 661         struct knote *kn = ap->a_kn;
 662         struct tty *tp = dev->si_tty;
 663         struct klist *klist;
 664
 665         ap->a_result = 0;
 666         switch (kn->kn_filter) {
 667         case EVFILT_READ:
 668                 klist = &tp->t_rsel.si_note;
 669                 kn->kn_fop = &ptcread_filtops;
 670                 break;
 671         case EVFILT_WRITE:
 672                 klist = &tp->t_wsel.si_note;
 673                 kn->kn_fop = &ptcwrite_filtops;
 674                 break;
 675         default:
 676                 ap->a_result = EOPNOTSUPP;
 677                 return (0);
 678         }
 679
 680         kn->kn_hook = (caddr_t)dev;
 681
 682         crit_enter();
 683         SLIST_INSERT_HEAD(klist, kn, kn_selnext);
 684         crit_exit();
 685
 686         return (0);
 687 }
 688
 689 static int
 690 filt_ptcread (struct knote *kn, long hint)
 691 {
 692         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 693         struct pt_ioctl *pti = ((cdev_t)kn->kn_hook)->si_drv1;
 694
 695         if (tp->t_state & TS_ZOMBIE) {
 696                 kn->kn_flags |= EV_EOF;
 697                 return (1);
 698         }
 699
 700         if ((tp->t_state & TS_ISOPEN) &&
 701             ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
 702              ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
 703              ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))) {
 704                 kn->kn_data = tp->t_outq.c_cc;
 705                 return(1);
 706         } else {
 707                 return(0);
 708         }
 709 }
 710
 711 static int
 712 filt_ptcwrite (struct knote *kn, long hint)
 713 {
 714         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 715         struct pt_ioctl *pti = ((cdev_t)kn->kn_hook)->si_drv1;
 716
 717         if (tp->t_state & TS_ZOMBIE) {
 718                 kn->kn_flags |= EV_EOF;
 719                 return (1);
 720         }
 721
 722         if (tp->t_state & TS_ISOPEN &&
 723             ((pti->pt_flags & PF_REMOTE) ?
 724              (tp->t_canq.c_cc == 0) :
 725              ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
 726               (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON))))) {
 727                 kn->kn_data = tp->t_canq.c_cc + tp->t_rawq.c_cc;
 728                 return(1);
 729         } else {
 730                 return(0);
 731         }
 732 }
 733
 734 static void
 735 filt_ptcrdetach (struct knote *kn)
 736 {
 737         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 738
 739         crit_enter();
 740         SLIST_REMOVE(&tp->t_rsel.si_note, kn, knote, kn_selnext);
 741         crit_exit();
 742 }
 743
 744 static void
 745 filt_ptcwdetach (struct knote *kn)
 746 {
 747         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 748
 749         crit_enter();
 750         SLIST_REMOVE(&tp->t_wsel.si_note, kn, knote, kn_selnext);
 751         crit_exit();
 752 }
 753
 754 /*
 755  * I/O ops
 756  */
 757 static  int
 758 ptcwrite(struct dev_write_args *ap)
 759 {
 760         cdev_t dev = ap->a_head.a_dev;
 761         struct tty *tp = dev->si_tty;
 762         u_char *cp = 0;
 763         int cc = 0;
 764         u_char locbuf[BUFSIZ];
 765         int cnt = 0;
 766         struct pt_ioctl *pti = dev->si_drv1;
 767         int error = 0;
 768
 769 again:
 770         if ((tp->t_state&TS_ISOPEN) == 0)
 771                 goto block;
 772         if (pti->pt_flags & PF_REMOTE) {
 773                 if (tp->t_canq.c_cc)
 774                         goto block;
 775                 while ((ap->a_uio->uio_resid > 0 || cc > 0) &&
 776                        tp->t_canq.c_cc < TTYHOG - 1) {
 777                         if (cc == 0) {
 778                                 cc = (int)szmin(ap->a_uio->uio_resid, BUFSIZ);
 779                                 cc = imin(cc, TTYHOG - 1 - tp->t_canq.c_cc);
 780                                 cp = locbuf;
 781                                 error = uiomove(cp, (size_t)cc, ap->a_uio);
 782                                 if (error)
 783                                         return (error);
 784                                 /* check again for safety */
 785                                 if ((tp->t_state & TS_ISOPEN) == 0) {
 786                                         /* adjust as usual */
 787                                         ap->a_uio->uio_resid += cc;
 788                                         return (EIO);
 789                                 }
 790                         }
 791                         if (cc > 0) {
 792                                 cc = b_to_q((char *)cp, cc, &tp->t_canq);
 793                                 /*
 794                                  * XXX we don't guarantee that the canq size
 795                                  * is >= TTYHOG, so the above b_to_q() may
 796                                  * leave some bytes uncopied.  However, space
 797                                  * is guaranteed for the null terminator if
 798                                  * we don't fail here since (TTYHOG - 1) is
 799                                  * not a multiple of CBSIZE.
 800                                  */
 801                                 if (cc > 0)
 802                                         break;
 803                         }
 804                 }
 805                 /* adjust for data copied in but not written */
 806                 ap->a_uio->uio_resid += cc;
 807                 clist_putc(0, &tp->t_canq);
 808                 ttwakeup(tp);
 809                 wakeup(TSA_PTS_READ(tp));
 810                 return (0);
 811         }
 812         while (ap->a_uio->uio_resid > 0 || cc > 0) {
 813                 if (cc == 0) {
 814                         cc = (int)szmin(ap->a_uio->uio_resid, BUFSIZ);
 815                         cp = locbuf;
 816                         error = uiomove(cp, (size_t)cc, ap->a_uio);
 817                         if (error)
 818                                 return (error);
 819                         /* check again for safety */
 820                         if ((tp->t_state & TS_ISOPEN) == 0) {
 821                                 /* adjust for data copied in but not written */
 822                                 ap->a_uio->uio_resid += cc;
 823                                 return (EIO);
 824                         }
 825                 }
 826                 while (cc > 0) {
 827                         if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
 828                            (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
 829                                 wakeup(TSA_HUP_OR_INPUT(tp));
 830                                 goto block;
 831                         }
 832                         (*linesw[tp->t_line].l_rint)(*cp++, tp);
 833                         cnt++;
 834                         cc--;
 835                 }
 836                 cc = 0;
 837         }
 838         return (0);
 839 block:
 840         /*
 841          * Come here to wait for slave to open, for space
 842          * in outq, or space in rawq, or an empty canq.
 843          */
 844         if ((tp->t_state & TS_CONNECTED) == 0) {
 845                 /* adjust for data copied in but not written */
 846                 ap->a_uio->uio_resid += cc;
 847                 return (EIO);
 848         }
 849         if (ap->a_ioflag & IO_NDELAY) {
 850                 /* adjust for data copied in but not written */
 851                 ap->a_uio->uio_resid += cc;
 852                 if (cnt == 0)
 853                         return (EWOULDBLOCK);
 854                 return (0);
 855         }
 856         error = tsleep(TSA_PTC_WRITE(tp), PCATCH, "ptcout", 0);
 857         if (error) {
 858                 /* adjust for data copied in but not written */
 859                 ap->a_uio->uio_resid += cc;
 860                 return (error);
 861         }
 862         goto again;
 863 }
 864
 865 /*ARGSUSED*/
 866 static  int
 867 ptyioctl(struct dev_ioctl_args *ap)
 868 {
 869         cdev_t dev = ap->a_head.a_dev;
 870         struct tty *tp = dev->si_tty;
 871         struct pt_ioctl *pti = dev->si_drv1;
 872         u_char *cc = tp->t_cc;
 873         int stop, error;
 874
 875         if (dev_dflags(dev) & D_MASTER) {
 876                 switch (ap->a_cmd) {
 877
 878                 case TIOCGPGRP:
 879                         /*
 880                          * We avoid calling ttioctl on the controller since,
 881                          * in that case, tp must be the controlling terminal.
 882                          */
 883                         *(int *)ap->a_data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
 884                         return (0);
 885
 886                 case TIOCPKT:
 887                         if (*(int *)ap->a_data) {
 888                                 if (pti->pt_flags & PF_UCNTL)
 889                                         return (EINVAL);
 890                                 pti->pt_flags |= PF_PKT;
 891                         } else
 892                                 pti->pt_flags &= ~PF_PKT;
 893                         return (0);
 894
 895                 case TIOCUCNTL:
 896                         if (*(int *)ap->a_data) {
 897                                 if (pti->pt_flags & PF_PKT)
 898                                         return (EINVAL);
 899                                 pti->pt_flags |= PF_UCNTL;
 900                         } else
 901                                 pti->pt_flags &= ~PF_UCNTL;
 902                         return (0);
 903
 904                 case TIOCREMOTE:
 905                         if (*(int *)ap->a_data)
 906                                 pti->pt_flags |= PF_REMOTE;
 907                         else
 908                                 pti->pt_flags &= ~PF_REMOTE;
 909                         ttyflush(tp, FREAD|FWRITE);
 910                         return (0);
 911
 912                 case TIOCISPTMASTER:
 913                         if ((pti->pt_flags2 & PF_UNIX98) && (pti->devc == dev))
 914                                 return (0);
 915                         else
 916                                 return (EINVAL);
 917                 }
 918
 919                 /*
 920                  * The rest of the ioctls shouldn't be called until
 921                  * the slave is open.
 922                  */
 923                 if ((tp->t_state & TS_ISOPEN) == 0)
 924                         return (EAGAIN);
 925
 926                 switch (ap->a_cmd) {
 927 #ifdef COMPAT_43
 928                 case TIOCSETP:
 929                 case TIOCSETN:
 930 #endif
 931                 case TIOCSETD:
 932                 case TIOCSETA:
 933                 case TIOCSETAW:
 934                 case TIOCSETAF:
 935                         /*
 936                          * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
 937                          * ttywflush(tp) will hang if there are characters in
 938                          * the outq.
 939                          */
 940                         ndflush(&tp->t_outq, tp->t_outq.c_cc);
 941                         break;
 942
 943                 case TIOCSIG:
 944                         if (*(unsigned int *)ap->a_data >= NSIG ||
 945                             *(unsigned int *)ap->a_data == 0)
 946                                 return(EINVAL);
 947                         if ((tp->t_lflag&NOFLSH) == 0)
 948                                 ttyflush(tp, FREAD|FWRITE);
 949                         pgsignal(tp->t_pgrp, *(unsigned int *)ap->a_data, 1);
 950                         if ((*(unsigned int *)ap->a_data == SIGINFO) &&
 951                             ((tp->t_lflag&NOKERNINFO) == 0))
 952                                 ttyinfo(tp);
 953                         return(0);
 954                 }
 955         }
 956         if (ap->a_cmd == TIOCEXT) {
 957                 /*
 958                  * When the EXTPROC bit is being toggled, we need
 959                  * to send an TIOCPKT_IOCTL if the packet driver
 960                  * is turned on.
 961                  */
 962                 if (*(int *)ap->a_data) {
 963                         if (pti->pt_flags & PF_PKT) {
 964                                 pti->pt_send |= TIOCPKT_IOCTL;
 965                                 ptcwakeup(tp, FREAD);
 966                         }
 967                         tp->t_lflag |= EXTPROC;
 968                 } else {
 969                         if ((tp->t_lflag & EXTPROC) &&
 970                             (pti->pt_flags & PF_PKT)) {
 971                                 pti->pt_send |= TIOCPKT_IOCTL;
 972                                 ptcwakeup(tp, FREAD);
 973                         }
 974                         tp->t_lflag &= ~EXTPROC;
 975                 }
 976                 return(0);
 977         }
 978         error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data,
 979                                               ap->a_fflag, ap->a_cred);
 980         if (error == ENOIOCTL)
 981                  error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
 982         if (error == ENOIOCTL) {
 983                 if (pti->pt_flags & PF_UCNTL &&
 984                     (ap->a_cmd & ~0xff) == UIOCCMD(0)) {
 985                         if (ap->a_cmd & 0xff) {
 986                                 pti->pt_ucntl = (u_char)ap->a_cmd;
 987                                 ptcwakeup(tp, FREAD);
 988                         }
 989                         return (0);
 990                 }
 991                 error = ENOTTY;
 992         }
 993         /*
 994          * If external processing and packet mode send ioctl packet.
 995          */
 996         if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
 997                 switch(ap->a_cmd) {
 998                 case TIOCSETA:
 999                 case TIOCSETAW:
1000                 case TIOCSETAF:
1001 #ifdef COMPAT_43
1002                 case TIOCSETP:
1003                 case TIOCSETN:
1004 #endif
1005 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
1006                 case TIOCSETC:
1007                 case TIOCSLTC:
1008                 case TIOCLBIS:
1009                 case TIOCLBIC:
1010                 case TIOCLSET:
1011 #endif
1012                         pti->pt_send |= TIOCPKT_IOCTL;
1013                         ptcwakeup(tp, FREAD);
1014                 default:
1015                         break;
1016                 }
1017         }
1018         stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
1019                 && CCEQ(cc[VSTART], CTRL('q'));
1020         if (pti->pt_flags & PF_NOSTOP) {
1021                 if (stop) {
1022                         pti->pt_send &= ~TIOCPKT_NOSTOP;
1023                         pti->pt_send |= TIOCPKT_DOSTOP;
1024                         pti->pt_flags &= ~PF_NOSTOP;
1025                         ptcwakeup(tp, FREAD);
1026                 }
1027         } else {
1028                 if (!stop) {
1029                         pti->pt_send &= ~TIOCPKT_DOSTOP;
1030                         pti->pt_send |= TIOCPKT_NOSTOP;
1031                         pti->pt_flags |= PF_NOSTOP;
1032                         ptcwakeup(tp, FREAD);
1033                 }
1034         }
1035         return (error);
1036 }
1037
1038
1039 static void ptc_drvinit (void *unused);
1040
1041 #ifdef UNIX98_PTYS
1042 SYSCTL_INT(_kern, OID_AUTO, pty_debug, CTLFLAG_RW, &pty_debug_level,
1043                 0, "Change pty debug level");
1044 #endif
1045
1046 static void
1047 ptc_drvinit(void *unused)
1048 {
1049         int i;
1050
1051 #ifdef UNIX98_PTYS
1052         /*
1053          * Unix98 pty stuff.
1054          * Create the clonable base device.
1055          */
1056         make_autoclone_dev(&ptc_ops, &DEVFS_CLONE_BITMAP(pty), ptyclone,
1057             0, 0, 0666, "ptmx");
1058 #endif
1059
1060         for (i = 0; i < 256; i++) {
1061                 ptyinit(i);
1062         }
1063 }
1064
1065 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)