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  kqinfo pt_kqr, pt_kqw;
 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         int uminor_no;
 321
 322         tp = dev->si_tty;
 323         uminor_no = dev->si_uminor;
 324         err = (*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
 325         ptsstop(tp, FREAD|FWRITE);
 326         (void) ttyclose(tp); /* clears t_state */
 327         tp->t_state |= TS_ZOMBIE;
 328
 329 #ifdef UNIX98_PTYS
 330         /*
 331          * Unix98 pty stuff.
 332          * On close of the slave, we unset the corresponding flag, and if the master
 333          * isn't open anymore, we destroy the slave and unset the unit.
 334          */
 335         ptydebug(1, "ptsclose=%s | unix98? %s\n", dev->si_name,
 336             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 337
 338         if (pti->pt_flags2 & PF_UNIX98) {
 339                 pti->pt_flags2 &= ~PF_SOPEN;
 340                 KKASSERT((pti->pt_flags2 & PF_SOPEN) == 0);
 341                 ptydebug(1, "master open? %s\n",
 342                     (pti->pt_flags2 & PF_MOPEN)?"yes":"no");
 343
 344                 if (!(pti->pt_flags2 & PF_SOPEN) &&
 345                     !(pti->pt_flags2 & PF_MOPEN)) {
 346                         destroy_dev(dev);
 347                         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(pty),
 348                                                uminor_no);
 349                         ttyunregister(&pti->pt_tty);
 350                         kfree(pti, M_PTY);
 351                 }
 352         }
 353 #endif
 354
 355         return (err);
 356 }
 357
 358 static  int
 359 ptsread(struct dev_read_args *ap)
 360 {
 361         cdev_t dev = ap->a_head.a_dev;
 362         struct proc *p = curproc;
 363         struct tty *tp = dev->si_tty;
 364         struct pt_ioctl *pti = dev->si_drv1;
 365         struct lwp *lp;
 366
 367         int error = 0;
 368
 369         lp = curthread->td_lwp;
 370
 371 again:
 372         if (pti->pt_flags & PF_REMOTE) {
 373                 while (isbackground(p, tp)) {
 374                         if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
 375                             SIGISMEMBER(lp->lwp_sigmask, SIGTTIN) ||
 376                             p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT)
 377                                 return (EIO);
 378                         pgsignal(p->p_pgrp, SIGTTIN, 1);
 379                         error = ttysleep(tp, &lbolt, PCATCH, "ptsbg", 0);
 380                         if (error)
 381                                 return (error);
 382                 }
 383                 if (tp->t_canq.c_cc == 0) {
 384                         if (ap->a_ioflag & IO_NDELAY)
 385                                 return (EWOULDBLOCK);
 386                         error = ttysleep(tp, TSA_PTS_READ(tp), PCATCH,
 387                                          "ptsin", 0);
 388                         if (error)
 389                                 return (error);
 390                         goto again;
 391                 }
 392                 while (tp->t_canq.c_cc > 1 && ap->a_uio->uio_resid > 0)
 393                         if (ureadc(clist_getc(&tp->t_canq), ap->a_uio) < 0) {
 394                                 error = EFAULT;
 395                                 break;
 396                         }
 397                 if (tp->t_canq.c_cc == 1)
 398                         clist_getc(&tp->t_canq);
 399                 if (tp->t_canq.c_cc)
 400                         return (error);
 401         } else
 402                 if (tp->t_oproc)
 403                         error = (*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag);
 404         ptcwakeup(tp, FWRITE);
 405         return (error);
 406 }
 407
 408 /*
 409  * Write to pseudo-tty.
 410  * Wakeups of controlling tty will happen
 411  * indirectly, when tty driver calls ptsstart.
 412  */
 413 static  int
 414 ptswrite(struct dev_write_args *ap)
 415 {
 416         cdev_t dev = ap->a_head.a_dev;
 417         struct tty *tp;
 418
 419         tp = dev->si_tty;
 420         if (tp->t_oproc == 0)
 421                 return (EIO);
 422         return ((*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag));
 423 }
 424
 425 /*
 426  * Start output on pseudo-tty.
 427  * Wake up process selecting or sleeping for input from controlling tty.
 428  */
 429 static void
 430 ptsstart(struct tty *tp)
 431 {
 432         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 433
 434         if (tp->t_state & TS_TTSTOP)
 435                 return;
 436         if (pti->pt_flags & PF_STOPPED) {
 437                 pti->pt_flags &= ~PF_STOPPED;
 438                 pti->pt_send = TIOCPKT_START;
 439         }
 440         ptcwakeup(tp, FREAD);
 441 }
 442
 443 static void
 444 ptcwakeup(struct tty *tp, int flag)
 445 {
 446         if (flag & FREAD) {
 447                 wakeup(TSA_PTC_READ(tp));
 448                 KNOTE(&tp->t_rkq.ki_note, 0);
 449         }
 450         if (flag & FWRITE) {
 451                 wakeup(TSA_PTC_WRITE(tp));
 452                 KNOTE(&tp->t_wkq.ki_note, 0);
 453         }
 454 }
 455
 456 static  int
 457 ptcopen(struct dev_open_args *ap)
 458 {
 459         cdev_t dev = ap->a_head.a_dev;
 460         struct tty *tp;
 461         struct pt_ioctl *pti;
 462
 463         if (!dev->si_drv1)
 464                 ptyinit(minor(dev));
 465         if (!dev->si_drv1)
 466                 return(ENXIO);
 467         pti = dev->si_drv1;
 468         if (pti->pt_prison && pti->pt_prison != ap->a_cred->cr_prison)
 469                 return(EBUSY);
 470         tp = dev->si_tty;
 471         if (tp->t_oproc)
 472                 return (EIO);
 473         tp->t_oproc = ptsstart;
 474         tp->t_stop = ptsstop;
 475         (void)(*linesw[tp->t_line].l_modem)(tp, 1);
 476         tp->t_lflag &= ~EXTPROC;
 477         pti->pt_prison = ap->a_cred->cr_prison;
 478         pti->pt_flags = 0;
 479         pti->pt_send = 0;
 480         pti->pt_ucntl = 0;
 481
 482         pti->devs->si_uid = ap->a_cred->cr_uid;
 483         pti->devs->si_gid = 0;
 484         pti->devs->si_perms = 0600;
 485         pti->devc->si_uid = ap->a_cred->cr_uid;
 486         pti->devc->si_gid = 0;
 487         pti->devc->si_perms = 0600;
 488
 489 #ifdef UNIX98_PTYS
 490         /*
 491          * Unix98 pty stuff.
 492          * On open of the master, we set the corresponding flag in the common
 493          * struct.
 494          */
 495         ptydebug(1, "ptcopen=%s (master) | unix98? %s\n", dev->si_name,
 496             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 497
 498         if (pti->pt_flags2 & PF_UNIX98) {
 499                 pti->pt_flags2 |= PF_MOPEN;
 500         }
 501 #endif
 502
 503         return (0);
 504 }
 505
 506 static  int
 507 ptcclose(struct dev_close_args *ap)
 508 {
 509         cdev_t dev = ap->a_head.a_dev;
 510         struct tty *tp;
 511         struct pt_ioctl *pti = dev->si_drv1;
 512         int uminor_no;
 513
 514         tp = dev->si_tty;
 515         uminor_no = dev->si_uminor;
 516         (void)(*linesw[tp->t_line].l_modem)(tp, 0);
 517
 518 #ifdef UNIX98_PTYS
 519         /*
 520          * Unix98 pty stuff.
 521          * On close of the master, we unset the corresponding flag in the common
 522          * struct asap.
 523          */
 524         pti->pt_flags2 &= ~PF_MOPEN;
 525 #endif
 526
 527         /*
 528          * XXX MDMBUF makes no sense for ptys but would inhibit the above
 529          * l_modem().  CLOCAL makes sense but isn't supported.   Special
 530          * l_modem()s that ignore carrier drop make no sense for ptys but
 531          * may be in use because other parts of the line discipline make
 532          * sense for ptys.  Recover by doing everything that a normal
 533          * ttymodem() would have done except for sending a SIGHUP.
 534          */
 535         if (tp->t_state & TS_ISOPEN) {
 536                 tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
 537                 tp->t_state |= TS_ZOMBIE;
 538                 ttyflush(tp, FREAD | FWRITE);
 539         }
 540         tp->t_oproc = 0;                /* mark closed */
 541
 542         pti = dev->si_drv1;
 543         pti->pt_prison = NULL;
 544         pti->devs->si_uid = 0;
 545         pti->devs->si_gid = 0;
 546         pti->devs->si_perms = 0666;
 547         pti->devc->si_uid = 0;
 548         pti->devc->si_gid = 0;
 549         pti->devc->si_perms = 0666;
 550
 551 #ifdef UNIX98_PTYS
 552         /*
 553          * Unix98 pty stuff.
 554          * On close of the master, we destroy the master and, if no slaves are open,
 555          * we destroy the slave device and unset the unit.
 556          */
 557         ptydebug(1, "ptcclose=%s (master) | unix98? %s\n", dev->si_name,
 558             (pti->pt_flags2 & PF_UNIX98)?"yes":"no");
 559         if (pti->pt_flags2 & PF_UNIX98) {
 560                 KKASSERT((pti->pt_flags2 & PF_MOPEN) == 0);
 561                 destroy_dev(dev);
 562                 pti->devc = NULL;
 563
 564                 if (!(pti->pt_flags2 & PF_SOPEN)) {
 565                         ptydebug(1, "ptcclose: slaves are not open\n");
 566                         destroy_dev(pti->devs);
 567                         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(pty),
 568                                                uminor_no);
 569                         ttyunregister(&pti->pt_tty);
 570                         kfree(pti, M_PTY);
 571                 }
 572         }
 573 #endif
 574
 575         return (0);
 576 }
 577
 578 static  int
 579 ptcread(struct dev_read_args *ap)
 580 {
 581         cdev_t dev = ap->a_head.a_dev;
 582         struct tty *tp = dev->si_tty;
 583         struct pt_ioctl *pti = dev->si_drv1;
 584         char buf[BUFSIZ];
 585         int error = 0, cc;
 586
 587         /*
 588          * We want to block until the slave
 589          * is open, and there's something to read;
 590          * but if we lost the slave or we're NBIO,
 591          * then return the appropriate error instead.
 592          */
 593         for (;;) {
 594                 if (tp->t_state&TS_ISOPEN) {
 595                         if (pti->pt_flags&PF_PKT && pti->pt_send) {
 596                                 error = ureadc((int)pti->pt_send, ap->a_uio);
 597                                 if (error)
 598                                         return (error);
 599                                 if (pti->pt_send & TIOCPKT_IOCTL) {
 600                                         cc = (int)szmin(ap->a_uio->uio_resid,
 601                                                         sizeof(tp->t_termios));
 602                                         uiomove((caddr_t)&tp->t_termios, cc,
 603                                                 ap->a_uio);
 604                                 }
 605                                 pti->pt_send = 0;
 606                                 return (0);
 607                         }
 608                         if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) {
 609                                 error = ureadc((int)pti->pt_ucntl, ap->a_uio);
 610                                 if (error)
 611                                         return (error);
 612                                 pti->pt_ucntl = 0;
 613                                 return (0);
 614                         }
 615                         if (tp->t_outq.c_cc && (tp->t_state&TS_TTSTOP) == 0)
 616                                 break;
 617                 }
 618                 if ((tp->t_state & TS_CONNECTED) == 0)
 619                         return (0);     /* EOF */
 620                 if (ap->a_ioflag & IO_NDELAY)
 621                         return (EWOULDBLOCK);
 622                 error = tsleep(TSA_PTC_READ(tp), PCATCH, "ptcin", 0);
 623                 if (error)
 624                         return (error);
 625         }
 626         if (pti->pt_flags & (PF_PKT|PF_UCNTL))
 627                 error = ureadc(0, ap->a_uio);
 628         while (ap->a_uio->uio_resid > 0 && error == 0) {
 629                 cc = q_to_b(&tp->t_outq, buf,
 630                             (int)szmin(ap->a_uio->uio_resid, BUFSIZ));
 631                 if (cc <= 0)
 632                         break;
 633                 error = uiomove(buf, (size_t)cc, ap->a_uio);
 634         }
 635         ttwwakeup(tp);
 636         return (error);
 637 }
 638
 639 static  void
 640 ptsstop(struct tty *tp, int flush)
 641 {
 642         struct pt_ioctl *pti = tp->t_dev->si_drv1;
 643         int flag;
 644
 645         /* note: FLUSHREAD and FLUSHWRITE already ok */
 646         if (flush == 0) {
 647                 flush = TIOCPKT_STOP;
 648                 pti->pt_flags |= PF_STOPPED;
 649         } else
 650                 pti->pt_flags &= ~PF_STOPPED;
 651         pti->pt_send |= flush;
 652         /* change of perspective */
 653         flag = 0;
 654         if (flush & FREAD)
 655                 flag |= FWRITE;
 656         if (flush & FWRITE)
 657                 flag |= FREAD;
 658         ptcwakeup(tp, flag);
 659 }
 660
 661 /*
 662  * kqueue ops for pseudo-terminals.
 663  */
 664 static struct filterops ptcread_filtops =
 665         { FILTEROP_ISFD, NULL, filt_ptcrdetach, filt_ptcread };
 666 static struct filterops ptcwrite_filtops =
 667         { FILTEROP_ISFD, NULL, filt_ptcwdetach, filt_ptcwrite };
 668
 669 static  int
 670 ptckqfilter(struct dev_kqfilter_args *ap)
 671 {
 672         cdev_t dev = ap->a_head.a_dev;
 673         struct knote *kn = ap->a_kn;
 674         struct tty *tp = dev->si_tty;
 675         struct klist *klist;
 676
 677         ap->a_result = 0;
 678         switch (kn->kn_filter) {
 679         case EVFILT_READ:
 680                 klist = &tp->t_rkq.ki_note;
 681                 kn->kn_fop = &ptcread_filtops;
 682                 break;
 683         case EVFILT_WRITE:
 684                 klist = &tp->t_wkq.ki_note;
 685                 kn->kn_fop = &ptcwrite_filtops;
 686                 break;
 687         default:
 688                 ap->a_result = EOPNOTSUPP;
 689                 return (0);
 690         }
 691
 692         kn->kn_hook = (caddr_t)dev;
 693         knote_insert(klist, kn);
 694         return (0);
 695 }
 696
 697 static int
 698 filt_ptcread (struct knote *kn, long hint)
 699 {
 700         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 701         struct pt_ioctl *pti = ((cdev_t)kn->kn_hook)->si_drv1;
 702
 703         if (tp->t_state & TS_ZOMBIE) {
 704                 kn->kn_flags |= EV_EOF;
 705                 return (1);
 706         }
 707
 708         if ((tp->t_state & TS_ISOPEN) &&
 709             ((tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) ||
 710              ((pti->pt_flags & PF_PKT) && pti->pt_send) ||
 711              ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))) {
 712                 kn->kn_data = tp->t_outq.c_cc;
 713                 return(1);
 714         } else {
 715                 return(0);
 716         }
 717 }
 718
 719 static int
 720 filt_ptcwrite (struct knote *kn, long hint)
 721 {
 722         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 723         struct pt_ioctl *pti = ((cdev_t)kn->kn_hook)->si_drv1;
 724
 725         if (tp->t_state & TS_ZOMBIE) {
 726                 kn->kn_flags |= EV_EOF;
 727                 return (1);
 728         }
 729
 730         if (tp->t_state & TS_ISOPEN &&
 731             ((pti->pt_flags & PF_REMOTE) ?
 732              (tp->t_canq.c_cc == 0) :
 733              ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG - 2) ||
 734               (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON))))) {
 735                 kn->kn_data = tp->t_canq.c_cc + tp->t_rawq.c_cc;
 736                 return(1);
 737         } else {
 738                 return(0);
 739         }
 740 }
 741
 742 static void
 743 filt_ptcrdetach (struct knote *kn)
 744 {
 745         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 746
 747         knote_remove(&tp->t_rkq.ki_note, kn);
 748 }
 749
 750 static void
 751 filt_ptcwdetach (struct knote *kn)
 752 {
 753         struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
 754
 755         knote_remove(&tp->t_wkq.ki_note, kn);
 756 }
 757
 758 /*
 759  * I/O ops
 760  */
 761 static  int
 762 ptcwrite(struct dev_write_args *ap)
 763 {
 764         cdev_t dev = ap->a_head.a_dev;
 765         struct tty *tp = dev->si_tty;
 766         u_char *cp = 0;
 767         int cc = 0;
 768         u_char locbuf[BUFSIZ];
 769         int cnt = 0;
 770         struct pt_ioctl *pti = dev->si_drv1;
 771         int error = 0;
 772
 773 again:
 774         if ((tp->t_state&TS_ISOPEN) == 0)
 775                 goto block;
 776         if (pti->pt_flags & PF_REMOTE) {
 777                 if (tp->t_canq.c_cc)
 778                         goto block;
 779                 while ((ap->a_uio->uio_resid > 0 || cc > 0) &&
 780                        tp->t_canq.c_cc < TTYHOG - 1) {
 781                         if (cc == 0) {
 782                                 cc = (int)szmin(ap->a_uio->uio_resid, BUFSIZ);
 783                                 cc = imin(cc, TTYHOG - 1 - tp->t_canq.c_cc);
 784                                 cp = locbuf;
 785                                 error = uiomove(cp, (size_t)cc, ap->a_uio);
 786                                 if (error)
 787                                         return (error);
 788                                 /* check again for safety */
 789                                 if ((tp->t_state & TS_ISOPEN) == 0) {
 790                                         /* adjust as usual */
 791                                         ap->a_uio->uio_resid += cc;
 792                                         return (EIO);
 793                                 }
 794                         }
 795                         if (cc > 0) {
 796                                 cc = b_to_q((char *)cp, cc, &tp->t_canq);
 797                                 /*
 798                                  * XXX we don't guarantee that the canq size
 799                                  * is >= TTYHOG, so the above b_to_q() may
 800                                  * leave some bytes uncopied.  However, space
 801                                  * is guaranteed for the null terminator if
 802                                  * we don't fail here since (TTYHOG - 1) is
 803                                  * not a multiple of CBSIZE.
 804                                  */
 805                                 if (cc > 0)
 806                                         break;
 807                         }
 808                 }
 809                 /* adjust for data copied in but not written */
 810                 ap->a_uio->uio_resid += cc;
 811                 clist_putc(0, &tp->t_canq);
 812                 ttwakeup(tp);
 813                 wakeup(TSA_PTS_READ(tp));
 814                 return (0);
 815         }
 816         while (ap->a_uio->uio_resid > 0 || cc > 0) {
 817                 if (cc == 0) {
 818                         cc = (int)szmin(ap->a_uio->uio_resid, BUFSIZ);
 819                         cp = locbuf;
 820                         error = uiomove(cp, (size_t)cc, ap->a_uio);
 821                         if (error)
 822                                 return (error);
 823                         /* check again for safety */
 824                         if ((tp->t_state & TS_ISOPEN) == 0) {
 825                                 /* adjust for data copied in but not written */
 826                                 ap->a_uio->uio_resid += cc;
 827                                 return (EIO);
 828                         }
 829                 }
 830                 while (cc > 0) {
 831                         if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 &&
 832                            (tp->t_canq.c_cc > 0 || !(tp->t_lflag&ICANON))) {
 833                                 wakeup(TSA_HUP_OR_INPUT(tp));
 834                                 goto block;
 835                         }
 836                         (*linesw[tp->t_line].l_rint)(*cp++, tp);
 837                         cnt++;
 838                         cc--;
 839                 }
 840                 cc = 0;
 841         }
 842         return (0);
 843 block:
 844         /*
 845          * Come here to wait for slave to open, for space
 846          * in outq, or space in rawq, or an empty canq.
 847          */
 848         if ((tp->t_state & TS_CONNECTED) == 0) {
 849                 /* adjust for data copied in but not written */
 850                 ap->a_uio->uio_resid += cc;
 851                 return (EIO);
 852         }
 853         if (ap->a_ioflag & IO_NDELAY) {
 854                 /* adjust for data copied in but not written */
 855                 ap->a_uio->uio_resid += cc;
 856                 if (cnt == 0)
 857                         return (EWOULDBLOCK);
 858                 return (0);
 859         }
 860         error = tsleep(TSA_PTC_WRITE(tp), PCATCH, "ptcout", 0);
 861         if (error) {
 862                 /* adjust for data copied in but not written */
 863                 ap->a_uio->uio_resid += cc;
 864                 return (error);
 865         }
 866         goto again;
 867 }
 868
 869 /*ARGSUSED*/
 870 static  int
 871 ptyioctl(struct dev_ioctl_args *ap)
 872 {
 873         cdev_t dev = ap->a_head.a_dev;
 874         struct tty *tp = dev->si_tty;
 875         struct pt_ioctl *pti = dev->si_drv1;
 876         u_char *cc = tp->t_cc;
 877         int stop, error;
 878
 879         if (dev_dflags(dev) & D_MASTER) {
 880                 switch (ap->a_cmd) {
 881
 882                 case TIOCGPGRP:
 883                         /*
 884                          * We avoid calling ttioctl on the controller since,
 885                          * in that case, tp must be the controlling terminal.
 886                          */
 887                         *(int *)ap->a_data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0;
 888                         return (0);
 889
 890                 case TIOCPKT:
 891                         if (*(int *)ap->a_data) {
 892                                 if (pti->pt_flags & PF_UCNTL)
 893                                         return (EINVAL);
 894                                 pti->pt_flags |= PF_PKT;
 895                         } else
 896                                 pti->pt_flags &= ~PF_PKT;
 897                         return (0);
 898
 899                 case TIOCUCNTL:
 900                         if (*(int *)ap->a_data) {
 901                                 if (pti->pt_flags & PF_PKT)
 902                                         return (EINVAL);
 903                                 pti->pt_flags |= PF_UCNTL;
 904                         } else
 905                                 pti->pt_flags &= ~PF_UCNTL;
 906                         return (0);
 907
 908                 case TIOCREMOTE:
 909                         if (*(int *)ap->a_data)
 910                                 pti->pt_flags |= PF_REMOTE;
 911                         else
 912                                 pti->pt_flags &= ~PF_REMOTE;
 913                         ttyflush(tp, FREAD|FWRITE);
 914                         return (0);
 915
 916                 case TIOCISPTMASTER:
 917                         if ((pti->pt_flags2 & PF_UNIX98) && (pti->devc == dev))
 918                                 return (0);
 919                         else
 920                                 return (EINVAL);
 921                 }
 922
 923                 /*
 924                  * The rest of the ioctls shouldn't be called until
 925                  * the slave is open.
 926                  */
 927                 if ((tp->t_state & TS_ISOPEN) == 0)
 928                         return (EAGAIN);
 929
 930                 switch (ap->a_cmd) {
 931 #ifdef COMPAT_43
 932                 case TIOCSETP:
 933                 case TIOCSETN:
 934 #endif
 935                 case TIOCSETD:
 936                 case TIOCSETA:
 937                 case TIOCSETAW:
 938                 case TIOCSETAF:
 939                         /*
 940                          * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
 941                          * ttywflush(tp) will hang if there are characters in
 942                          * the outq.
 943                          */
 944                         ndflush(&tp->t_outq, tp->t_outq.c_cc);
 945                         break;
 946
 947                 case TIOCSIG:
 948                         if (*(unsigned int *)ap->a_data >= NSIG ||
 949                             *(unsigned int *)ap->a_data == 0)
 950                                 return(EINVAL);
 951                         if ((tp->t_lflag&NOFLSH) == 0)
 952                                 ttyflush(tp, FREAD|FWRITE);
 953                         pgsignal(tp->t_pgrp, *(unsigned int *)ap->a_data, 1);
 954                         if ((*(unsigned int *)ap->a_data == SIGINFO) &&
 955                             ((tp->t_lflag&NOKERNINFO) == 0))
 956                                 ttyinfo(tp);
 957                         return(0);
 958                 }
 959         }
 960         if (ap->a_cmd == TIOCEXT) {
 961                 /*
 962                  * When the EXTPROC bit is being toggled, we need
 963                  * to send an TIOCPKT_IOCTL if the packet driver
 964                  * is turned on.
 965                  */
 966                 if (*(int *)ap->a_data) {
 967                         if (pti->pt_flags & PF_PKT) {
 968                                 pti->pt_send |= TIOCPKT_IOCTL;
 969                                 ptcwakeup(tp, FREAD);
 970                         }
 971                         tp->t_lflag |= EXTPROC;
 972                 } else {
 973                         if ((tp->t_lflag & EXTPROC) &&
 974                             (pti->pt_flags & PF_PKT)) {
 975                                 pti->pt_send |= TIOCPKT_IOCTL;
 976                                 ptcwakeup(tp, FREAD);
 977                         }
 978                         tp->t_lflag &= ~EXTPROC;
 979                 }
 980                 return(0);
 981         }
 982         error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data,
 983                                               ap->a_fflag, ap->a_cred);
 984         if (error == ENOIOCTL)
 985                  error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
 986         if (error == ENOIOCTL) {
 987                 if (pti->pt_flags & PF_UCNTL &&
 988                     (ap->a_cmd & ~0xff) == UIOCCMD(0)) {
 989                         if (ap->a_cmd & 0xff) {
 990                                 pti->pt_ucntl = (u_char)ap->a_cmd;
 991                                 ptcwakeup(tp, FREAD);
 992                         }
 993                         return (0);
 994                 }
 995                 error = ENOTTY;
 996         }
 997         /*
 998          * If external processing and packet mode send ioctl packet.
 999          */
1000         if ((tp->t_lflag&EXTPROC) && (pti->pt_flags & PF_PKT)) {
1001                 switch(ap->a_cmd) {
1002                 case TIOCSETA:
1003                 case TIOCSETAW:
1004                 case TIOCSETAF:
1005 #ifdef COMPAT_43
1006                 case TIOCSETP:
1007                 case TIOCSETN:
1008 #endif
1009 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
1010                 case TIOCSETC:
1011                 case TIOCSLTC:
1012                 case TIOCLBIS:
1013                 case TIOCLBIC:
1014                 case TIOCLSET:
1015 #endif
1016                         pti->pt_send |= TIOCPKT_IOCTL;
1017                         ptcwakeup(tp, FREAD);
1018                 default:
1019                         break;
1020                 }
1021         }
1022         stop = (tp->t_iflag & IXON) && CCEQ(cc[VSTOP], CTRL('s'))
1023                 && CCEQ(cc[VSTART], CTRL('q'));
1024         if (pti->pt_flags & PF_NOSTOP) {
1025                 if (stop) {
1026                         pti->pt_send &= ~TIOCPKT_NOSTOP;
1027                         pti->pt_send |= TIOCPKT_DOSTOP;
1028                         pti->pt_flags &= ~PF_NOSTOP;
1029                         ptcwakeup(tp, FREAD);
1030                 }
1031         } else {
1032                 if (!stop) {
1033                         pti->pt_send &= ~TIOCPKT_DOSTOP;
1034                         pti->pt_send |= TIOCPKT_NOSTOP;
1035                         pti->pt_flags |= PF_NOSTOP;
1036                         ptcwakeup(tp, FREAD);
1037                 }
1038         }
1039         return (error);
1040 }
1041
1042
1043 static void ptc_drvinit (void *unused);
1044
1045 #ifdef UNIX98_PTYS
1046 SYSCTL_INT(_kern, OID_AUTO, pty_debug, CTLFLAG_RW, &pty_debug_level,
1047                 0, "Change pty debug level");
1048 #endif
1049
1050 static void
1051 ptc_drvinit(void *unused)
1052 {
1053         int i;
1054
1055 #ifdef UNIX98_PTYS
1056         /*
1057          * Unix98 pty stuff.
1058          * Create the clonable base device.
1059          */
1060         make_autoclone_dev(&ptc_ops, &DEVFS_CLONE_BITMAP(pty), ptyclone,
1061             0, 0, 0666, "ptmx");
1062 #endif
1063
1064         for (i = 0; i < 256; i++) {
1065                 ptyinit(i);
1066         }
1067 }
1068
1069 SYSINIT(ptcdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR_C,ptc_drvinit,NULL)