/* $NetBSD: tty_pty.c,v 1.78 2004/05/27 03:56:49 christos Exp $ */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)tty_pty.c 8.4 (Berkeley) 2/20/95 */ /* * Pseudo-teletype Driver * (Actually two drivers, requiring two entries in 'cdevsw') * Additional multiplexor driver /dev/ptm{,x} */ #include __KERNEL_RCSID(0, "$NetBSD: tty_pty.c,v 1.78 2004/05/27 03:56:49 christos Exp $"); #include "opt_compat_sunos.h" #include "pty.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DEFAULT_NPTYS 16 /* default number of initial ptys */ #define DEFAULT_MAXPTYS 992 /* default maximum number of ptys */ #ifdef DEBUG_PTM #define DPRINTF(a) uprintf a #else #define DPRINTF(a) #endif /* Macros to clear/set/test flags. */ #define SET(t, f) (t) |= (f) #define CLR(t, f) (t) &= ~((unsigned)(f)) #define ISSET(t, f) ((t) & (f)) #define BUFSIZ 100 /* Chunk size iomoved to/from user */ /* * pts == /dev/tty[pqrs]? * ptc == /dev/pty[pqrs]? */ #define TTY_TEMPLATE "/dev/XtyXX" #define TTY_NAMESIZE sizeof(TTY_TEMPLATE) /* XXX this needs to come from somewhere sane, and work with MAKEDEV */ #define TTY_LETTERS "pqrstuvwxyzPQRST" #define TTY_OLD_SUFFIX "0123456789abcdef" #define TTY_NEW_SUFFIX "ghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" struct pt_softc { struct tty *pt_tty; int pt_flags; struct selinfo pt_selr, pt_selw; u_char pt_send; u_char pt_ucntl; }; static struct pt_softc **pt_softc = NULL; /* pty array */ static int npty = 0; /* for pstat -t */ static int maxptys = DEFAULT_MAXPTYS; /* maximum number of ptys (sysctable) */ static struct simplelock pt_softc_mutex = SIMPLELOCK_INITIALIZER; #define PF_PKT 0x08 /* packet mode */ #define PF_STOPPED 0x10 /* user told stopped */ #define PF_REMOTE 0x20 /* remote and flow controlled input */ #define PF_NOSTOP 0x40 #define PF_UCNTL 0x80 /* user control mode */ void ptyattach(int); void ptcwakeup(struct tty *, int); void ptsstart(struct tty *); int pty_maxptys(int, int); static struct pt_softc **ptyarralloc(int); static int check_pty(int); #ifdef NPTM static int pts_major; static dev_t pty_getfree(void); static char *pty_makename(char *, dev_t, char); static int pty_grant_slave(struct proc *, dev_t); static int pty_alloc_master(struct proc *, int *, dev_t *); static int pty_alloc_slave(struct proc *, int *, dev_t); static void pty_fill_ptmget(dev_t, int, int, void *); void ptmattach(int); dev_type_open(ptmopen); dev_type_close(ptmclose); dev_type_ioctl(ptmioctl); const struct cdevsw ptm_cdevsw = { ptmopen, ptmclose, noread, nowrite, ptmioctl, nullstop, notty, nopoll, nommap, nokqfilter, D_TTY }; #endif dev_type_open(ptcopen); dev_type_close(ptcclose); dev_type_read(ptcread); dev_type_write(ptcwrite); dev_type_poll(ptcpoll); dev_type_kqfilter(ptckqfilter); dev_type_open(ptsopen); dev_type_close(ptsclose); dev_type_read(ptsread); dev_type_write(ptswrite); dev_type_stop(ptsstop); dev_type_poll(ptspoll); dev_type_ioctl(ptyioctl); dev_type_tty(ptytty); const struct cdevsw ptc_cdevsw = { ptcopen, ptcclose, ptcread, ptcwrite, ptyioctl, nullstop, ptytty, ptcpoll, nommap, ptckqfilter, D_TTY }; const struct cdevsw pts_cdevsw = { ptsopen, ptsclose, ptsread, ptswrite, ptyioctl, ptsstop, ptytty, ptspoll, nommap, ttykqfilter, D_TTY }; #if defined(pmax) const struct cdevsw ptc_ultrix_cdevsw = { ptcopen, ptcclose, ptcread, ptcwrite, ptyioctl, nullstop, ptytty, ptcpoll, nommap, ptckqfilter, D_TTY }; const struct cdevsw pts_ultrix_cdevsw = { ptsopen, ptsclose, ptsread, ptswrite, ptyioctl, ptsstop, ptytty, ptspoll, nommap, ttykqfilter, D_TTY }; #endif /* defined(pmax) */ /* * Allocate and zero array of nelem elements. */ static struct pt_softc ** ptyarralloc(nelem) int nelem; { struct pt_softc **pt; nelem += 10; pt = malloc(nelem * sizeof *pt, M_DEVBUF, M_WAITOK | M_ZERO); return pt; } /* * Check if the minor is correct and ensure necessary structures * are properly allocated. */ static int check_pty(int ptn) { struct pt_softc *pti; if (ptn >= npty) { struct pt_softc **newpt, **oldpt; int newnpty; /* check if the requested pty can be granted */ if (ptn >= maxptys) { limit_reached: tablefull("pty", "increase kern.maxptys"); return (ENXIO); } /* Allocate a larger pty array */ for (newnpty = npty; newnpty <= ptn;) newnpty *= 2; if (newnpty > maxptys) newnpty = maxptys; newpt = ptyarralloc(newnpty); /* * Now grab the pty array mutex - we need to ensure * that the pty array is consistent while copying it's * content to newly allocated, larger space; we also * need to be safe against pty_maxptys(). */ simple_lock(&pt_softc_mutex); if (newnpty >= maxptys) { /* limit cut away beneath us... */ newnpty = maxptys; if (ptn >= newnpty) { simple_unlock(&pt_softc_mutex); free(newpt, M_DEVBUF); goto limit_reached; } } /* * If the pty array was not enlarged while we were waiting * for mutex, copy current contents of pt_softc[] to newly * allocated array and start using the new bigger array. */ if (newnpty > npty) { memcpy(newpt, pt_softc, npty*sizeof(struct pt_softc *)); oldpt = pt_softc; pt_softc = newpt; npty = newnpty; } else { /* was enlarged when waited for lock, free new space */ oldpt = newpt; } simple_unlock(&pt_softc_mutex); free(oldpt, M_DEVBUF); } /* * If the entry is not yet allocated, allocate one. The mutex is * needed so that the state of pt_softc[] array is consistant * in case it has been lengthened above. */ if (!pt_softc[ptn]) { MALLOC(pti, struct pt_softc *, sizeof(struct pt_softc), M_DEVBUF, M_WAITOK); memset(pti, 0, sizeof(struct pt_softc)); pti->pt_tty = ttymalloc(); simple_lock(&pt_softc_mutex); /* * Check the entry again - it might have been * added while we were waiting for mutex. */ if (!pt_softc[ptn]) { tty_attach(pti->pt_tty); pt_softc[ptn] = pti; } else { ttyfree(pti->pt_tty); free(pti, M_DEVBUF); } simple_unlock(&pt_softc_mutex); } return (0); } /* * Set maxpty in thread-safe way. Returns 0 in case of error, otherwise * new value of maxptys. */ int pty_maxptys(newmax, set) int newmax, set; { if (!set) return (maxptys); /* * We have to grab the pt_softc lock, so that we would pick correct * value of npty (might be modified in check_pty()). */ simple_lock(&pt_softc_mutex); /* * The value cannot be set to value lower than the highest pty * number ever allocated. */ if (newmax >= npty) maxptys = newmax; else newmax = 0; simple_unlock(&pt_softc_mutex); return newmax; } /* * Establish n (or default if n is 1) ptys in the system. */ void ptyattach(n) int n; { /* maybe should allow 0 => none? */ if (n <= 1) n = DEFAULT_NPTYS; pt_softc = ptyarralloc(n); npty = n; } /*ARGSUSED*/ int ptsopen(dev, flag, devtype, p) dev_t dev; int flag, devtype; struct proc *p; { struct pt_softc *pti; struct tty *tp; int error; int ptn = minor(dev); int s; if ((error = check_pty(ptn))) return (error); pti = pt_softc[ptn]; tp = pti->pt_tty; if (!ISSET(tp->t_state, TS_ISOPEN)) { ttychars(tp); /* Set up default chars */ tp->t_iflag = TTYDEF_IFLAG; tp->t_oflag = TTYDEF_OFLAG; tp->t_lflag = TTYDEF_LFLAG; tp->t_cflag = TTYDEF_CFLAG; tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; ttsetwater(tp); /* would be done in xxparam() */ } else if (ISSET(tp->t_state, TS_XCLUDE) && p->p_ucred->cr_uid != 0) return (EBUSY); if (tp->t_oproc) /* Ctrlr still around. */ SET(tp->t_state, TS_CARR_ON); if (!ISSET(flag, O_NONBLOCK)) { s = spltty(); TTY_LOCK(tp); while (!ISSET(tp->t_state, TS_CARR_ON)) { tp->t_wopen++; error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH, ttopen, 0); tp->t_wopen--; if (error) { TTY_UNLOCK(tp); splx(s); return (error); } } TTY_UNLOCK(tp); splx(s); } error = (*tp->t_linesw->l_open)(dev, tp); ptcwakeup(tp, FREAD|FWRITE); return (error); } int ptsclose(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int error; error = (*tp->t_linesw->l_close)(tp, flag); error |= ttyclose(tp); ptcwakeup(tp, FREAD|FWRITE); return (error); } int ptsread(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct proc *p = curproc; struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int error = 0; int cc; int s; again: if (pti->pt_flags & PF_REMOTE) { while (isbackground(p, tp)) { if (sigismasked(p, SIGTTIN) || p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT) return (EIO); pgsignal(p->p_pgrp, SIGTTIN, 1); s = spltty(); TTY_LOCK(tp); error = ttysleep(tp, (caddr_t)&lbolt, TTIPRI | PCATCH | PNORELOCK, ttybg, 0); splx(s); if (error) return (error); } s = spltty(); TTY_LOCK(tp); if (tp->t_canq.c_cc == 0) { if (flag & IO_NDELAY) { TTY_UNLOCK(tp); splx(s); return (EWOULDBLOCK); } error = ttysleep(tp, (caddr_t)&tp->t_canq, TTIPRI | PCATCH | PNORELOCK, ttyin, 0); if (error) return (error); goto again; } while(error == 0 && tp->t_canq.c_cc > 1 && uio->uio_resid > 0) { TTY_UNLOCK(tp); splx(s); error = ureadc(getc(&tp->t_canq), uio); s = spltty(); TTY_LOCK(tp); /* Re-check terminal state here? */ } if (tp->t_canq.c_cc == 1) (void) getc(&tp->t_canq); cc = tp->t_canq.c_cc; TTY_UNLOCK(tp); splx(s); if (cc) return (error); } else if (tp->t_oproc) error = (*tp->t_linesw->l_read)(tp, uio, flag); ptcwakeup(tp, FWRITE); return (error); } /* * Write to pseudo-tty. * Wakeups of controlling tty will happen * indirectly, when tty driver calls ptsstart. */ int ptswrite(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; if (tp->t_oproc == 0) return (EIO); return ((*tp->t_linesw->l_write)(tp, uio, flag)); } /* * Poll pseudo-tty. */ int ptspoll(dev, events, p) dev_t dev; int events; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; if (tp->t_oproc == 0) return (EIO); return ((*tp->t_linesw->l_poll)(tp, events, p)); } /* * Start output on pseudo-tty. * Wake up process polling or sleeping for input from controlling tty. * Called with tty slock held. */ void ptsstart(tp) struct tty *tp; { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; if (ISSET(tp->t_state, TS_TTSTOP)) return; if (pti->pt_flags & PF_STOPPED) { pti->pt_flags &= ~PF_STOPPED; pti->pt_send = TIOCPKT_START; } selnotify(&pti->pt_selr, NOTE_SUBMIT); wakeup((caddr_t)&tp->t_outq.c_cf); } /* * Stop output. * Called with tty slock held. */ void ptsstop(tp, flush) struct tty *tp; int flush; { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; /* note: FLUSHREAD and FLUSHWRITE already ok */ if (flush == 0) { flush = TIOCPKT_STOP; pti->pt_flags |= PF_STOPPED; } else pti->pt_flags &= ~PF_STOPPED; pti->pt_send |= flush; /* change of perspective */ if (flush & FREAD) { selnotify(&pti->pt_selw, NOTE_SUBMIT); wakeup((caddr_t)&tp->t_rawq.c_cf); } if (flush & FWRITE) { selnotify(&pti->pt_selr, NOTE_SUBMIT); wakeup((caddr_t)&tp->t_outq.c_cf); } } void ptcwakeup(tp, flag) struct tty *tp; int flag; { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; int s; s = spltty(); TTY_LOCK(tp); if (flag & FREAD) { selnotify(&pti->pt_selr, NOTE_SUBMIT); wakeup((caddr_t)&tp->t_outq.c_cf); } if (flag & FWRITE) { selnotify(&pti->pt_selw, NOTE_SUBMIT); wakeup((caddr_t)&tp->t_rawq.c_cf); } TTY_UNLOCK(tp); splx(s); } /*ARGSUSED*/ int ptcopen(dev, flag, devtype, p) dev_t dev; int flag, devtype; struct proc *p; { struct pt_softc *pti; struct tty *tp; int error; int ptn = minor(dev); int s; if ((error = check_pty(ptn))) return (error); pti = pt_softc[ptn]; tp = pti->pt_tty; s = spltty(); TTY_LOCK(tp); if (tp->t_oproc) { TTY_UNLOCK(tp); splx(s); return (EIO); } tp->t_oproc = ptsstart; TTY_UNLOCK(tp); splx(s); (void)(*tp->t_linesw->l_modem)(tp, 1); CLR(tp->t_lflag, EXTPROC); pti->pt_flags = 0; pti->pt_send = 0; pti->pt_ucntl = 0; return (0); } /*ARGSUSED*/ int ptcclose(dev, flag, devtype, p) dev_t dev; int flag, devtype; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int s; (void)(*tp->t_linesw->l_modem)(tp, 0); CLR(tp->t_state, TS_CARR_ON); s = spltty(); TTY_LOCK(tp); tp->t_oproc = 0; /* mark closed */ TTY_UNLOCK(tp); splx(s); return (0); } int ptcread(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; u_char buf[BUFSIZ]; int error = 0, cc; int s; /* * We want to block until the slave * is open, and there's something to read; * but if we lost the slave or we're NBIO, * then return the appropriate error instead. */ s = spltty(); TTY_LOCK(tp); for (;;) { if (ISSET(tp->t_state, TS_ISOPEN)) { if (pti->pt_flags & PF_PKT && pti->pt_send) { TTY_UNLOCK(tp); splx(s); error = ureadc((int)pti->pt_send, uio); if (error) return (error); /* * Since we don't have the tty locked, there's * a risk of messing up `t_termios'. This is * relevant only if the tty got closed and then * opened again while we were out uiomoving. */ if (pti->pt_send & TIOCPKT_IOCTL) { cc = min(uio->uio_resid, sizeof(tp->t_termios)); uiomove((caddr_t) &tp->t_termios, cc, uio); } pti->pt_send = 0; return (0); } if (pti->pt_flags & PF_UCNTL && pti->pt_ucntl) { TTY_UNLOCK(tp); splx(s); error = ureadc((int)pti->pt_ucntl, uio); if (error) return (error); pti->pt_ucntl = 0; return (0); } if (tp->t_outq.c_cc && !ISSET(tp->t_state, TS_TTSTOP)) break; } if (!ISSET(tp->t_state, TS_CARR_ON)) { error = 0; /* EOF */ goto out; } if (flag & IO_NDELAY) { error = EWOULDBLOCK; goto out; } error = ltsleep((caddr_t)&tp->t_outq.c_cf, TTIPRI | PCATCH, ttyin, 0, &tp->t_slock); if (error) goto out; } if (pti->pt_flags & (PF_PKT|PF_UCNTL)) { TTY_UNLOCK(tp); splx(s); error = ureadc(0, uio); s = spltty(); TTY_LOCK(tp); if (error == 0 && !ISSET(tp->t_state, TS_ISOPEN)) error = EIO; } while (uio->uio_resid > 0 && error == 0) { cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ)); if (cc <= 0) break; TTY_UNLOCK(tp); splx(s); error = uiomove(buf, cc, uio); s = spltty(); TTY_LOCK(tp); if (error == 0 && !ISSET(tp->t_state, TS_ISOPEN)) error = EIO; } if (tp->t_outq.c_cc <= tp->t_lowat) { if (ISSET(tp->t_state, TS_ASLEEP)) { CLR(tp->t_state, TS_ASLEEP); wakeup((caddr_t)&tp->t_outq); } selnotify(&tp->t_wsel, NOTE_SUBMIT); } out: TTY_UNLOCK(tp); splx(s); return (error); } int ptcwrite(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; u_char *cp = NULL; int cc = 0; u_char locbuf[BUFSIZ]; int cnt = 0; int error = 0; int s; again: s = spltty(); TTY_LOCK(tp); if (!ISSET(tp->t_state, TS_ISOPEN)) goto block; if (pti->pt_flags & PF_REMOTE) { if (tp->t_canq.c_cc) goto block; while (uio->uio_resid > 0 && tp->t_canq.c_cc < TTYHOG - 1) { if (cc == 0) { cc = min(uio->uio_resid, BUFSIZ); cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc); cp = locbuf; TTY_UNLOCK(tp); splx(s); error = uiomove((caddr_t)cp, cc, uio); if (error) return (error); s = spltty(); TTY_LOCK(tp); /* check again for safety */ if (!ISSET(tp->t_state, TS_ISOPEN)) { error = EIO; goto out; } } if (cc) (void) b_to_q(cp, cc, &tp->t_canq); cc = 0; } (void) putc(0, &tp->t_canq); ttwakeup(tp); wakeup((caddr_t)&tp->t_canq); error = 0; goto out; } while (uio->uio_resid > 0) { if (cc == 0) { cc = min(uio->uio_resid, BUFSIZ); cp = locbuf; TTY_UNLOCK(tp); splx(s); error = uiomove((caddr_t)cp, cc, uio); if (error) return (error); s = spltty(); TTY_LOCK(tp); /* check again for safety */ if (!ISSET(tp->t_state, TS_ISOPEN)) { error = EIO; goto out; } } while (cc > 0) { if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 && (tp->t_canq.c_cc > 0 || !ISSET(tp->t_lflag, ICANON))) { wakeup((caddr_t)&tp->t_rawq); goto block; } /* XXX - should change l_rint to be called with lock * see also tty.c:ttyinput_wlock() */ TTY_UNLOCK(tp); splx(s); (*tp->t_linesw->l_rint)(*cp++, tp); s = spltty(); TTY_LOCK(tp); cnt++; cc--; } cc = 0; } error = 0; goto out; block: /* * Come here to wait for slave to open, for space * in outq, or space in rawq. */ if (!ISSET(tp->t_state, TS_CARR_ON)) { error = EIO; goto out; } if (flag & IO_NDELAY) { /* adjust for data copied in but not written */ uio->uio_resid += cc; error = cnt == 0 ? EWOULDBLOCK : 0; goto out; } error = ltsleep((caddr_t)&tp->t_rawq.c_cf, TTOPRI | PCATCH | PNORELOCK, ttyout, 0, &tp->t_slock); splx(s); if (error) { /* adjust for data copied in but not written */ uio->uio_resid += cc; return (error); } goto again; out: TTY_UNLOCK(tp); splx(s); return (error); } int ptcpoll(dev, events, p) dev_t dev; int events; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int revents = 0; int s = splsoftclock(); if (events & (POLLIN | POLLRDNORM)) if (ISSET(tp->t_state, TS_ISOPEN) && ((tp->t_outq.c_cc > 0 && !ISSET(tp->t_state, TS_TTSTOP)) || ((pti->pt_flags & PF_PKT) && pti->pt_send) || ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))) revents |= events & (POLLIN | POLLRDNORM); if (events & (POLLOUT | POLLWRNORM)) if (ISSET(tp->t_state, TS_ISOPEN) && ((pti->pt_flags & PF_REMOTE) ? (tp->t_canq.c_cc == 0) : ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) || (tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON))))) revents |= events & (POLLOUT | POLLWRNORM); if (events & POLLHUP) if (!ISSET(tp->t_state, TS_CARR_ON)) revents |= POLLHUP; if (revents == 0) { if (events & (POLLIN | POLLHUP | POLLRDNORM)) selrecord(p, &pti->pt_selr); if (events & (POLLOUT | POLLWRNORM)) selrecord(p, &pti->pt_selw); } splx(s); return (revents); } static void filt_ptcrdetach(struct knote *kn) { struct pt_softc *pti; int s; pti = kn->kn_hook; s = spltty(); SLIST_REMOVE(&pti->pt_selr.sel_klist, kn, knote, kn_selnext); splx(s); } static int filt_ptcread(struct knote *kn, long hint) { struct pt_softc *pti; struct tty *tp; int canread; pti = kn->kn_hook; tp = pti->pt_tty; canread = (ISSET(tp->t_state, TS_ISOPEN) && ((tp->t_outq.c_cc > 0 && !ISSET(tp->t_state, TS_TTSTOP)) || ((pti->pt_flags & PF_PKT) && pti->pt_send) || ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))); if (canread) { /* * c_cc is number of characters after output post-processing; * the amount of data actually read(2) depends on * setting of input flags for the terminal. */ kn->kn_data = tp->t_outq.c_cc; if (((pti->pt_flags & PF_PKT) && pti->pt_send) || ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)) kn->kn_data++; } return (canread); } static void filt_ptcwdetach(struct knote *kn) { struct pt_softc *pti; int s; pti = kn->kn_hook; s = spltty(); SLIST_REMOVE(&pti->pt_selw.sel_klist, kn, knote, kn_selnext); splx(s); } static int filt_ptcwrite(struct knote *kn, long hint) { struct pt_softc *pti; struct tty *tp; int canwrite; int nwrite; pti = kn->kn_hook; tp = pti->pt_tty; canwrite = (ISSET(tp->t_state, TS_ISOPEN) && ((pti->pt_flags & PF_REMOTE) ? (tp->t_canq.c_cc == 0) : ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) || (tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON))))); if (canwrite) { if (pti->pt_flags & PF_REMOTE) nwrite = tp->t_canq.c_cn; else { /* this is guaranteed to be > 0 due to above check */ nwrite = tp->t_canq.c_cn - (tp->t_rawq.c_cc + tp->t_canq.c_cc); } kn->kn_data = nwrite; } return (canwrite); } static const struct filterops ptcread_filtops = { 1, NULL, filt_ptcrdetach, filt_ptcread }; static const struct filterops ptcwrite_filtops = { 1, NULL, filt_ptcwdetach, filt_ptcwrite }; int ptckqfilter(dev_t dev, struct knote *kn) { struct pt_softc *pti = pt_softc[minor(dev)]; struct klist *klist; int s; switch (kn->kn_filter) { case EVFILT_READ: klist = &pti->pt_selr.sel_klist; kn->kn_fop = &ptcread_filtops; break; case EVFILT_WRITE: klist = &pti->pt_selw.sel_klist; kn->kn_fop = &ptcwrite_filtops; break; default: return (1); } kn->kn_hook = pti; s = spltty(); SLIST_INSERT_HEAD(klist, kn, kn_selnext); splx(s); return (0); } struct tty * ptytty(dev) dev_t dev; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; return (tp); } /*ARGSUSED*/ int ptyioctl(dev, cmd, data, flag, p) dev_t dev; u_long cmd; caddr_t data; int flag; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; const struct cdevsw *cdev; u_char *cc = tp->t_cc; int stop, error, sig; int s; cdev = cdevsw_lookup(dev); /* * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG. * ttywflush(tp) will hang if there are characters in the outq. */ if (cmd == TIOCEXT) { /* * When the EXTPROC bit is being toggled, we need * to send an TIOCPKT_IOCTL if the packet driver * is turned on. */ if (*(int *)data) { if (pti->pt_flags & PF_PKT) { pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); } SET(tp->t_lflag, EXTPROC); } else { if (ISSET(tp->t_lflag, EXTPROC) && (pti->pt_flags & PF_PKT)) { pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); } CLR(tp->t_lflag, EXTPROC); } return(0); } if (cdev != NULL && cdev->d_open == ptcopen) switch (cmd) { #ifdef NPTM case TIOCGRANTPT: return pty_grant_slave(p, dev); case TIOCPTSNAME: pty_fill_ptmget(dev, -1, -1, data); return 0; #endif case TIOCGPGRP: /* * We avoid calling ttioctl on the controller since, * in that case, tp must be the controlling terminal. */ *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; return (0); case TIOCPKT: if (*(int *)data) { if (pti->pt_flags & PF_UCNTL) return (EINVAL); pti->pt_flags |= PF_PKT; } else pti->pt_flags &= ~PF_PKT; return (0); case TIOCUCNTL: if (*(int *)data) { if (pti->pt_flags & PF_PKT) return (EINVAL); pti->pt_flags |= PF_UCNTL; } else pti->pt_flags &= ~PF_UCNTL; return (0); case TIOCREMOTE: if (*(int *)data) pti->pt_flags |= PF_REMOTE; else pti->pt_flags &= ~PF_REMOTE; s = spltty(); TTY_LOCK(tp); ttyflush(tp, FREAD|FWRITE); TTY_UNLOCK(tp); splx(s); return (0); #ifdef COMPAT_OLDTTY case TIOCSETP: case TIOCSETN: #endif case TIOCSETD: case TIOCSETA: case TIOCSETAW: case TIOCSETAF: TTY_LOCK(tp); ndflush(&tp->t_outq, tp->t_outq.c_cc); TTY_UNLOCK(tp); break; case TIOCSIG: sig = (int)(long)*(caddr_t *)data; if (sig <= 0 || sig >= NSIG) return (EINVAL); TTY_LOCK(tp); if (!ISSET(tp->t_lflag, NOFLSH)) ttyflush(tp, FREAD|FWRITE); if ((sig == SIGINFO) && (!ISSET(tp->t_lflag, NOKERNINFO))) ttyinfo(tp); TTY_UNLOCK(tp); pgsignal(tp->t_pgrp, sig, 1); return(0); } error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p); if (error == EPASSTHROUGH) error = ttioctl(tp, cmd, data, flag, p); if (error == EPASSTHROUGH) { if (pti->pt_flags & PF_UCNTL && (cmd & ~0xff) == UIOCCMD(0)) { if (cmd & 0xff) { pti->pt_ucntl = (u_char)cmd; ptcwakeup(tp, FREAD); } return (0); } } /* * If external processing and packet mode send ioctl packet. */ if (ISSET(tp->t_lflag, EXTPROC) && (pti->pt_flags & PF_PKT)) { switch(cmd) { case TIOCSETA: case TIOCSETAW: case TIOCSETAF: #ifdef COMPAT_OLDTTY case TIOCSETP: case TIOCSETN: case TIOCSETC: case TIOCSLTC: case TIOCLBIS: case TIOCLBIC: case TIOCLSET: #endif pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); default: break; } } stop = ISSET(tp->t_iflag, IXON) && CCEQ(cc[VSTOP], CTRL('s')) && CCEQ(cc[VSTART], CTRL('q')); if (pti->pt_flags & PF_NOSTOP) { if (stop) { pti->pt_send &= ~TIOCPKT_NOSTOP; pti->pt_send |= TIOCPKT_DOSTOP; pti->pt_flags &= ~PF_NOSTOP; ptcwakeup(tp, FREAD); } } else { if (!stop) { pti->pt_send &= ~TIOCPKT_DOSTOP; pti->pt_send |= TIOCPKT_NOSTOP; pti->pt_flags |= PF_NOSTOP; ptcwakeup(tp, FREAD); } } return (error); } #ifdef NPTM /* * Check if a pty is free to use. */ static __inline int pty_isfree_locked(int minor) { struct pt_softc *pt = pt_softc[minor]; return (pt == NULL || pt->pt_tty == NULL || pt->pt_tty->t_oproc == NULL); } static int pty_isfree(int minor) { int isfree; simple_lock(&pt_softc_mutex); isfree = pty_isfree_locked(minor); simple_unlock(&pt_softc_mutex); return(isfree); } static char * pty_makename(char *buf, dev_t dev, char c) { size_t nt; dev_t minor = minor(dev); (void)memcpy(buf, TTY_TEMPLATE, TTY_NAMESIZE); buf[5] = c; if (minor < 256) { nt = sizeof(TTY_OLD_SUFFIX) - 1; buf[8] = TTY_LETTERS[minor / nt]; buf[9] = TTY_OLD_SUFFIX[minor % nt]; } else { minor -= 256; nt = sizeof(TTY_NEW_SUFFIX) - sizeof(TTY_OLD_SUFFIX); buf[8] = TTY_LETTERS[minor / nt]; buf[9] = TTY_NEW_SUFFIX[minor % nt]; } return buf; } static dev_t pty_getfree(void) { int i; simple_lock(&pt_softc_mutex); for (i = 0; i < npty; i++) { if (pty_isfree_locked(i)) break; } simple_unlock(&pt_softc_mutex); return (makedev(pts_major, i)); } /* * Hacked up version of vn_open. We _only_ handle ptys and only open * them with FREAD|FWRITE and never deal with creat or stuff like that. * * We need it because we have to fake up root credentials to open the pty. */ static int ptm_vn_open(struct nameidata *ndp) { struct vnode *vp; struct proc *p = ndp->ni_cnd.cn_proc; struct ucred *cred; int error; if ((error = namei(ndp)) != 0) return (error); vp = ndp->ni_vp; if (vp->v_type != VCHR) { error = EINVAL; goto bad; } /* * Get us a fresh cred with root privileges. */ cred = crget(); error = VOP_OPEN(vp, FREAD|FWRITE, cred, p); crfree(cred); if (error) goto bad; vp->v_writecount++; return (0); bad: vput(vp); return (error); } static int pty_alloc_master(struct proc *p, int *fd, dev_t *dev) { int error; struct nameidata nd; struct pt_softc *pti; struct file *fp; int md; char name[TTY_NAMESIZE]; if ((error = falloc(p, &fp, fd)) != 0) { DPRINTF(("falloc %d\n", error)); return error; } retry: /* Find and open a free master pty. */ *dev = pty_getfree(); md = minor(*dev); if ((error = check_pty(md)) != 0) { DPRINTF(("ckeck_pty %d\n", error)); goto bad; } pti = pt_softc[md]; NDINIT(&nd, LOOKUP, NOFOLLOW|LOCKLEAF, UIO_SYSSPACE, pty_makename(name, *dev, 'p'), p); if ((error = ptm_vn_open(&nd)) != 0) { /* * Check if the master open failed because we lost * the race to grab it. */ if (error == EIO && !pty_isfree(md)) goto retry; DPRINTF(("check_pty %d\n", error)); goto bad; } fp->f_flag = FREAD|FWRITE; fp->f_type = DTYPE_VNODE; fp->f_ops = &vnops; fp->f_data = nd.ni_vp; VOP_UNLOCK(nd.ni_vp, 0); FILE_SET_MATURE(fp); FILE_UNUSE(fp, p); return 0; bad: FILE_UNUSE(fp, p); fdremove(p->p_fd, *fd); ffree(fp); return error; } static int pty_grant_slave(struct proc *p, dev_t dev) { int error; struct nameidata nd; char name[TTY_NAMESIZE]; /* * Open the slave. * namei -> setattr -> unlock -> revoke -> vrele -> * namei -> open -> unlock * Three stage rocket: * 1. Change the owner and permissions on the slave. * 2. Revoke all the users of the slave. * 3. open the slave. */ NDINIT(&nd, LOOKUP, NOFOLLOW|LOCKLEAF, UIO_SYSSPACE, pty_makename(name, dev, 't'), p); if ((error = namei(&nd)) != 0) { DPRINTF(("namei %d\n", error)); return error; } if ((nd.ni_vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { struct vattr vattr; struct ucred *cred; gid_t gid = _TTY_GID; /* get real uid */ uid_t uid = p->p_cred->p_ruid; VATTR_NULL(&vattr); vattr.va_uid = uid; vattr.va_gid = gid; vattr.va_mode = (S_IRUSR|S_IWUSR|S_IWGRP) & ALLPERMS; /* Get a fake cred to pretend we're root. */ cred = crget(); error = VOP_SETATTR(nd.ni_vp, &vattr, cred, p); crfree(cred); if (error) { DPRINTF(("setattr %d\n", error)); VOP_UNLOCK(nd.ni_vp, 0); vrele(nd.ni_vp); return error; } } VOP_UNLOCK(nd.ni_vp, 0); if (nd.ni_vp->v_usecount > 1 || (nd.ni_vp->v_flag & (VALIASED | VLAYER))) VOP_REVOKE(nd.ni_vp, REVOKEALL); /* * The vnode is useless after the revoke, we need to * namei again. */ vrele(nd.ni_vp); return 0; } static int pty_alloc_slave(struct proc *p, int *fd, dev_t dev) { int error; struct file *fp; struct nameidata nd; char name[TTY_NAMESIZE]; /* Grab a filedescriptor for the slave */ if ((error = falloc(p, &fp, fd)) != 0) { DPRINTF(("falloc %d\n", error)); return error; } NDINIT(&nd, LOOKUP, NOFOLLOW|LOCKLEAF, UIO_SYSSPACE, pty_makename(name, dev, 't'), p); /* now open it */ if ((error = ptm_vn_open(&nd)) != 0) { DPRINTF(("vn_open %d\n", error)); FILE_UNUSE(fp, p); fdremove(p->p_fd, *fd); ffree(fp); return error; } fp->f_flag = FREAD|FWRITE; fp->f_type = DTYPE_VNODE; fp->f_ops = &vnops; fp->f_data = nd.ni_vp; VOP_UNLOCK(nd.ni_vp, 0); FILE_SET_MATURE(fp); FILE_UNUSE(fp, p); return 0; } static void pty_fill_ptmget(dev_t dev, int cfd, int sfd, void *data) { struct ptmget *ptm = data; ptm->cfd = cfd; ptm->sfd = sfd; (void)pty_makename(ptm->cn, dev, 'p'); (void)pty_makename(ptm->sn, dev, 't'); } void /*ARGSUSED*/ ptmattach(int n) { /* find the major and minor of the pty devices */ if ((pts_major = cdevsw_lookup_major(&pts_cdevsw)) == -1) panic("ptmattach: Can't find pty slave in cdevsw"); } int /*ARGSUSED*/ ptmopen(dev_t dev, int flag, int mode, struct proc *p) { int error; int fd; switch(minor(dev)) { case 0: /* /dev/ptmx */ if ((error = pty_alloc_master(p, &fd, &dev)) != 0) return error; curlwp->l_dupfd = fd; return ENXIO; case 1: /* /dev/ptm */ return 0; default: return ENODEV; } } int /*ARGSUSED*/ ptmclose(dev_t dev, int flag, int mode, struct proc *p) { return (0); } int /*ARGSUSED*/ ptmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p) { int error; dev_t newdev; int cfd, sfd; struct file *fp; error = 0; switch (cmd) { case TIOCPTMGET: if ((error = pty_alloc_master(p, &cfd, &newdev)) != 0) goto bad; if ((error = pty_grant_slave(p, newdev)) != 0) goto bad; if ((error = pty_alloc_slave(p, &sfd, newdev)) != 0) goto bad; /* now, put the indices and names into struct ptmget */ pty_fill_ptmget(newdev, cfd, sfd, data); return 0; default: DPRINTF(("ptmioctl EINVAL\n")); return EINVAL; } bad: fp = fd_getfile(p->p_fd, cfd); fdremove(p->p_fd, cfd); ffree(fp); return error; } #endif