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