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IABSD.fr/src/sys/kern/tty_pty.c
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- sys/kern/tty_pty.c
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/* $OpenBSD: tty_pty.c,v 1.115 2024/11/05 06:03:19 jsg Exp $ */ /* $NetBSD: tty_pty.c,v 1.33.4.1 1996/06/02 09:08:11 mrg 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') */ #include <sys/param.h> #include <sys/systm.h> #include <sys/namei.h> #include <sys/mount.h> #include <sys/ioctl.h> #include <sys/proc.h> #include <sys/tty.h> #include <sys/fcntl.h> #include <sys/file.h> #include <sys/filedesc.h> #include <sys/uio.h> #include <sys/kernel.h> #include <sys/malloc.h> #include <sys/vnode.h> #include <sys/signalvar.h> #include <sys/conf.h> #include <sys/stat.h> #include <sys/sysctl.h> #include <sys/pledge.h> #include <sys/rwlock.h> #define BUFSIZ 100 /* Chunk size iomoved to/from user */ /* * pts == /dev/tty[p-zP-T][0-9a-zA-Z] * ptc == /dev/pty[p-zP-T][0-9a-zA-Z] */ /* XXX this needs to come from somewhere sane, and work with MAKEDEV */ #define TTY_LETTERS "pqrstuvwxyzPQRST" #define TTY_SUFFIX "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" static int pts_major; struct pt_softc { struct tty *pt_tty; int pt_flags; struct selinfo pt_selr, pt_selw; u_char pt_send; u_char pt_ucntl; char pty_pn[11]; char pty_sn[11]; }; #define NPTY_MIN 8 /* number of initial ptys */ #define NPTY_MAX 992 /* maximum number of ptys supported */ static struct pt_softc **pt_softc = NULL; /* pty array */ static int npty = 0; /* size of pty array */ static int maxptys = NPTY_MAX; /* maximum number of ptys */ /* for pty array */ struct rwlock pt_softc_lock = RWLOCK_INITIALIZER("ptarrlk"); #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); struct tty *ptytty(dev_t); void ptsstart(struct tty *); int sysctl_pty(int *, u_int, void *, size_t *, void *, size_t); void filt_ptcrdetach(struct knote *); int filt_ptcread(struct knote *, long); void filt_ptcwdetach(struct knote *); int filt_ptcwrite(struct knote *, long); int filt_ptcexcept(struct knote *, long); static struct pt_softc **ptyarralloc(int); static int check_pty(int); static gid_t tty_gid = TTY_GID; void ptydevname(int, struct pt_softc *); dev_t pty_getfree(void); void ptmattach(int); int ptmopen(dev_t, int, int, struct proc *); int ptmclose(dev_t, int, int, struct proc *); int ptmioctl(dev_t, u_long, caddr_t, int, struct proc *p); static int ptm_vn_open(struct nameidata *); void ptydevname(int minor, struct pt_softc *pti) { char buf[11] = "/dev/XtyXX"; int i, j; i = minor / (sizeof(TTY_SUFFIX) - 1); j = minor % (sizeof(TTY_SUFFIX) - 1); if (i >= sizeof(TTY_LETTERS) - 1) { pti->pty_pn[0] = '\0'; pti->pty_sn[0] = '\0'; return; } buf[5] = 'p'; buf[8] = TTY_LETTERS[i]; buf[9] = TTY_SUFFIX[j]; memcpy(pti->pty_pn, buf, sizeof(buf)); buf[5] = 't'; memcpy(pti->pty_sn, buf, sizeof(buf)); } /* * Allocate and zero array of nelem elements. */ struct pt_softc ** ptyarralloc(int nelem) { struct pt_softc **pt; pt = mallocarray(nelem, sizeof(struct pt_softc *), M_DEVBUF, M_WAITOK|M_ZERO); return pt; } /* * Check if the minor is correct and ensure necessary structures * are properly allocated. */ int check_pty(int dev) { struct pt_softc *pti; int minor = minor(dev); rw_enter_write(&pt_softc_lock); if (minor >= npty) { struct pt_softc **newpt; int newnpty; /* check if the requested pty can be granted */ if (minor >= maxptys) goto limit_reached; /* grow pty array by powers of two, up to maxptys */ for (newnpty = npty; newnpty <= minor; newnpty *= 2) ; if (newnpty > maxptys) newnpty = maxptys; newpt = ptyarralloc(newnpty); memcpy(newpt, pt_softc, npty * sizeof(struct pt_softc *)); free(pt_softc, M_DEVBUF, npty * sizeof(struct pt_softc *)); pt_softc = newpt; npty = newnpty; } /* * If the entry is not yet allocated, allocate one. */ if (!pt_softc[minor]) { pti = malloc(sizeof(struct pt_softc), M_DEVBUF, M_WAITOK|M_ZERO); pti->pt_tty = ttymalloc(1000000); pti->pt_tty->t_dev = dev; ptydevname(minor, pti); pt_softc[minor] = pti; } rw_exit_write(&pt_softc_lock); return (0); limit_reached: rw_exit_write(&pt_softc_lock); tablefull("pty"); return (ENXIO); } /* * Establish n (or default if n is 1) ptys in the system. */ void ptyattach(int n) { /* maybe should allow 0 => none? */ if (n <= 1) n = NPTY_MIN; pt_softc = ptyarralloc(n); npty = n; /* * If we have pty, we need ptm too. */ ptmattach(1); } int ptsopen(dev_t dev, int flag, int devtype, struct proc *p) { struct pt_softc *pti; struct tty *tp; int error; if ((error = check_pty(dev))) return (error); pti = pt_softc[minor(dev)]; tp = pti->pt_tty; if ((tp->t_state & TS_ISOPEN) == 0) { tp->t_state |= TS_WOPEN; 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 = B115200; ttsetwater(tp); /* would be done in xxparam() */ } else if (tp->t_state & TS_XCLUDE && suser(p) != 0) return (EBUSY); if (tp->t_oproc) /* Ctrlr still around. */ tp->t_state |= TS_CARR_ON; while ((tp->t_state & TS_CARR_ON) == 0) { tp->t_state |= TS_WOPEN; if (flag & FNONBLOCK) break; error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH, ttopen); if (error) return (error); } error = (*linesw[tp->t_line].l_open)(dev, tp, p); ptcwakeup(tp, FREAD|FWRITE); return (error); } int ptsclose(dev_t dev, int flag, int mode, struct proc *p) { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int error; error = (*linesw[tp->t_line].l_close)(tp, flag, p); error |= ttyclose(tp); ptcwakeup(tp, FREAD|FWRITE); return (error); } int ptsread(dev_t dev, struct uio *uio, int flag) { struct proc *p = curproc; struct process *pr = p->p_p; struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int error = 0; again: if (pti->pt_flags & PF_REMOTE) { while (isbackground(pr, tp)) { if (sigismasked(p, SIGTTIN) || pr->ps_pgrp->pg_jobc == 0 || pr->ps_flags & PS_PPWAIT) return (EIO); pgsignal(pr->ps_pgrp, SIGTTIN, 1); error = ttysleep(tp, &lbolt, TTIPRI | PCATCH, ttybg); if (error) return (error); } if (tp->t_canq.c_cc == 0) { if (flag & IO_NDELAY) return (EWOULDBLOCK); error = ttysleep(tp, &tp->t_canq, TTIPRI | PCATCH, ttyin); if (error) return (error); goto again; } while (tp->t_canq.c_cc > 1 && uio->uio_resid > 0) if (ureadc(getc(&tp->t_canq), uio) < 0) { error = EFAULT; break; } if (tp->t_canq.c_cc == 1) (void) getc(&tp->t_canq); if (tp->t_canq.c_cc) return (error); } else if (tp->t_oproc) error = (*linesw[tp->t_line].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_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 == NULL) return (EIO); return ((*linesw[tp->t_line].l_write)(tp, uio, flag)); } /* * Start output on pseudo-tty. * Wake up process polling or sleeping for input from controlling tty. */ void ptsstart(struct tty *tp) { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; if (tp->t_state & TS_TTSTOP) return; if (pti->pt_flags & PF_STOPPED) { pti->pt_flags &= ~PF_STOPPED; pti->pt_send = TIOCPKT_START; } ptcwakeup(tp, FREAD); } int ptsstop(struct tty *tp, int flush) { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; int flag; /* 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 */ flag = 0; if (flush & FREAD) flag |= FWRITE; if (flush & FWRITE) flag |= FREAD; ptcwakeup(tp, flag); return 0; } void ptcwakeup(struct tty *tp, int flag) { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; if (flag & FREAD) { selwakeup(&pti->pt_selr); wakeup(&tp->t_outq.c_cf); } if (flag & FWRITE) { selwakeup(&pti->pt_selw); wakeup(&tp->t_rawq.c_cf); } } int ptcopen(dev_t, int, int, struct proc *); int ptcopen(dev_t dev, int flag, int devtype, struct proc *p) { struct pt_softc *pti; struct tty *tp; int error; if ((error = check_pty(dev))) return (error); pti = pt_softc[minor(dev)]; tp = pti->pt_tty; if (tp->t_oproc) return (EIO); tp->t_oproc = ptsstart; (void)(*linesw[tp->t_line].l_modem)(tp, 1); tp->t_lflag &= ~EXTPROC; pti->pt_flags = 0; pti->pt_send = 0; pti->pt_ucntl = 0; return (0); } int ptcclose(dev_t dev, int flag, int devtype, struct proc *p) { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; (void)(*linesw[tp->t_line].l_modem)(tp, 0); tp->t_state &= ~TS_CARR_ON; tp->t_oproc = NULL; /* mark closed */ return (0); } int ptcread(dev_t dev, struct uio *uio, int flag) { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; char buf[BUFSIZ]; int error = 0, cc, bufcc = 0; /* * 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. */ for (;;) { if (tp->t_state & TS_ISOPEN) { if (pti->pt_flags & PF_PKT && pti->pt_send) { error = ureadc((int)pti->pt_send, uio); if (error) return (error); if (pti->pt_send & TIOCPKT_IOCTL) { cc = MIN(uio->uio_resid, sizeof(tp->t_termios)); error = uiomove(&tp->t_termios, cc, uio); if (error) return (error); } pti->pt_send = 0; return (0); } if (pti->pt_flags & PF_UCNTL && pti->pt_ucntl) { error = ureadc((int)pti->pt_ucntl, uio); if (error) return (error); pti->pt_ucntl = 0; return (0); } if (tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) break; } if ((tp->t_state & TS_CARR_ON) == 0) return (0); /* EOF */ if (flag & IO_NDELAY) return (EWOULDBLOCK); error = tsleep_nsec(&tp->t_outq.c_cf, TTIPRI | PCATCH, ttyin, INFSLP); if (error) return (error); } if (pti->pt_flags & (PF_PKT|PF_UCNTL)) error = ureadc(0, uio); while (uio->uio_resid > 0 && error == 0) { cc = MIN(uio->uio_resid, BUFSIZ); cc = q_to_b(&tp->t_outq, buf, cc); if (cc > bufcc) bufcc = cc; if (cc <= 0) break; error = uiomove(buf, cc, uio); } ttwakeupwr(tp); if (bufcc) explicit_bzero(buf, bufcc); return (error); } int ptcwrite(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, bufcc = 0; u_char buf[BUFSIZ]; size_t cnt = 0; int error = 0; again: if ((tp->t_state & TS_ISOPEN) == 0) 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(tp) - 1) { if (cc == 0) { cc = MIN(uio->uio_resid, BUFSIZ); cc = min(cc, TTYHOG(tp) - 1 - tp->t_canq.c_cc); if (cc > bufcc) bufcc = cc; cp = buf; error = uiomove(cp, cc, uio); if (error) goto done; /* check again for safety */ if ((tp->t_state & TS_ISOPEN) == 0) { error = EIO; goto done; } } if (cc) (void) b_to_q((char *)cp, cc, &tp->t_canq); cc = 0; } (void) putc(0, &tp->t_canq); ttwakeup(tp); wakeup(&tp->t_canq); goto done; } do { if (cc == 0) { cc = MIN(uio->uio_resid, BUFSIZ); if (cc > bufcc) bufcc = cc; cp = buf; error = uiomove(cp, cc, uio); if (error) goto done; /* check again for safety */ if ((tp->t_state & TS_ISOPEN) == 0) { error = EIO; goto done; } } bufcc = cc; while (cc > 0) { if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG(tp) - 2 && (tp->t_canq.c_cc > 0 || !ISSET(tp->t_lflag, ICANON))) { wakeup(&tp->t_rawq); goto block; } if ((*linesw[tp->t_line].l_rint)(*cp++, tp) == 1 && tsleep(tp, TTIPRI | PCATCH, "ttyretype", 1) == EINTR) goto interrupt; cnt++; cc--; } cc = 0; } while (uio->uio_resid > 0); goto done; block: /* * Come here to wait for slave to open, for space * in outq, or space in rawq. */ if ((tp->t_state & TS_CARR_ON) == 0) { error = EIO; goto done; } if (flag & IO_NDELAY) { /* adjust for data copied in but not written */ uio->uio_resid += cc; if (cnt == 0) error = EWOULDBLOCK; goto done; } error = tsleep_nsec(&tp->t_rawq.c_cf, TTOPRI | PCATCH, ttyout, INFSLP); if (error == 0) goto again; interrupt: /* adjust for data copied in but not written */ uio->uio_resid += cc; done: if (bufcc) explicit_bzero(buf, bufcc); return (error); } void filt_ptcrdetach(struct knote *kn) { struct pt_softc *pti = (struct pt_softc *)kn->kn_hook; int s; s = spltty(); klist_remove_locked(&pti->pt_selr.si_note, kn); splx(s); } int filt_ptcread(struct knote *kn, long hint) { struct pt_softc *pti = (struct pt_softc *)kn->kn_hook; struct tty *tp; int active; tp = pti->pt_tty; kn->kn_data = 0; if (ISSET(tp->t_state, TS_ISOPEN)) { if (!ISSET(tp->t_state, TS_TTSTOP)) 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++; } active = (kn->kn_data > 0); if (!ISSET(tp->t_state, TS_CARR_ON)) { kn->kn_flags |= EV_EOF; if (kn->kn_flags & __EV_POLL) kn->kn_flags |= __EV_HUP; active = 1; } else { kn->kn_flags &= ~(EV_EOF | __EV_HUP); } return (active); } void filt_ptcwdetach(struct knote *kn) { struct pt_softc *pti = (struct pt_softc *)kn->kn_hook; int s; s = spltty(); klist_remove_locked(&pti->pt_selw.si_note, kn); splx(s); } int filt_ptcwrite(struct knote *kn, long hint) { struct pt_softc *pti = (struct pt_softc *)kn->kn_hook; struct tty *tp; int active; tp = pti->pt_tty; kn->kn_data = 0; if (ISSET(tp->t_state, TS_ISOPEN)) { if (ISSET(pti->pt_flags, PF_REMOTE)) { if (tp->t_canq.c_cc == 0) kn->kn_data = tp->t_canq.c_cn; } else if ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG(tp)-2) || (tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON))) kn->kn_data = tp->t_canq.c_cn - (tp->t_rawq.c_cc + tp->t_canq.c_cc); } active = (kn->kn_data > 0); /* Write-side HUP condition is only for poll(2) and select(2). */ if (kn->kn_flags & (__EV_POLL | __EV_SELECT)) { if (!ISSET(tp->t_state, TS_CARR_ON)) { kn->kn_flags |= __EV_HUP; active = 1; } else { kn->kn_flags &= ~__EV_HUP; } } return (active); } int filt_ptcexcept(struct knote *kn, long hint) { struct pt_softc *pti = (struct pt_softc *)kn->kn_hook; struct tty *tp; int active = 0; tp = pti->pt_tty; if (kn->kn_sfflags & NOTE_OOB) { /* If in packet or user control mode, check for data. */ if (((pti->pt_flags & PF_PKT) && pti->pt_send) || ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl)) { kn->kn_fflags |= NOTE_OOB; kn->kn_data = 1; active = 1; } } if (kn->kn_flags & __EV_POLL) { if (!ISSET(tp->t_state, TS_CARR_ON)) { kn->kn_flags |= __EV_HUP; active = 1; } else { kn->kn_flags &= ~__EV_HUP; } } return (active); } const struct filterops ptcread_filtops = { .f_flags = FILTEROP_ISFD, .f_attach = NULL, .f_detach = filt_ptcrdetach, .f_event = filt_ptcread, }; const struct filterops ptcwrite_filtops = { .f_flags = FILTEROP_ISFD, .f_attach = NULL, .f_detach = filt_ptcwdetach, .f_event = filt_ptcwrite, }; const struct filterops ptcexcept_filtops = { .f_flags = FILTEROP_ISFD, .f_attach = NULL, .f_detach = filt_ptcrdetach, .f_event = filt_ptcexcept, }; 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.si_note; kn->kn_fop = &ptcread_filtops; break; case EVFILT_WRITE: klist = &pti->pt_selw.si_note; kn->kn_fop = &ptcwrite_filtops; break; case EVFILT_EXCEPT: klist = &pti->pt_selr.si_note; kn->kn_fop = &ptcexcept_filtops; break; default: return (EINVAL); } kn->kn_hook = (caddr_t)pti; s = spltty(); klist_insert_locked(klist, kn); splx(s); return (0); } struct tty * ptytty(dev_t dev) { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; return (tp); } int ptyioctl(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; u_char *cc = tp->t_cc; int stop, error; /* * 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); } tp->t_lflag |= EXTPROC; } else { if ((tp->t_lflag & EXTPROC) && (pti->pt_flags & PF_PKT)) { pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); } tp->t_lflag &= ~EXTPROC; } return(0); } else if (cdevsw[major(dev)].d_open == ptcopen) switch (cmd) { 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; ttyflush(tp, FREAD|FWRITE); return (0); case TIOCSETD: case TIOCSETA: case TIOCSETAW: case TIOCSETAF: ndflush(&tp->t_outq, tp->t_outq.c_cc); break; case TIOCSIG: if (*(unsigned int *)data >= NSIG || *(unsigned int *)data == 0) return(EINVAL); if ((tp->t_lflag & NOFLSH) == 0) ttyflush(tp, FREAD|FWRITE); pgsignal(tp->t_pgrp, *(unsigned int *)data, 1); if ((*(unsigned int *)data == SIGINFO) && ((tp->t_lflag & NOKERNINFO) == 0)) ttyinfo(tp); return (0); case FIONREAD: /* * FIONREAD on the master side must return the amount * in the output queue rather than the input. */ *(int *)data = tp->t_outq.c_cc; return (0); } error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p); if (error < 0) error = ttioctl(tp, cmd, data, flag, p); if (error < 0) { /* * Translate TIOCSBRK/TIOCCBRK to user mode ioctls to * let the master interpret BREAK conditions. */ switch (cmd) { case TIOCSBRK: cmd = UIOCCMD(TIOCUCNTL_SBRK); break; case TIOCCBRK: cmd = UIOCCMD(TIOCUCNTL_CBRK); break; default: break; } if (pti->pt_flags & PF_UCNTL && (cmd & ~0xff) == UIOCCMD(0)) { if (cmd & 0xff) { pti->pt_ucntl = (u_char)cmd; ptcwakeup(tp, FREAD); } return (0); } error = ENOTTY; } /* * If external processing and packet mode send ioctl packet. */ if ((tp->t_lflag & EXTPROC) && (pti->pt_flags & PF_PKT)) { switch (cmd) { case TIOCSETA: case TIOCSETAW: case TIOCSETAF: pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); default: break; } } stop = (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); } /* * Return pty-related information. */ int sysctl_pty(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { if (namelen != 1) return (ENOTDIR); switch (name[0]) { default: return (EOPNOTSUPP); } /* NOTREACHED */ } /* * Check if a pty is free to use. */ static 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; rw_enter_read(&pt_softc_lock); isfree = pty_isfree_locked(minor); rw_exit_read(&pt_softc_lock); return(isfree); } dev_t pty_getfree(void) { int i; rw_enter_read(&pt_softc_lock); for (i = 0; i < npty; i++) { if (pty_isfree_locked(i)) break; } rw_exit_read(&pt_softc_lock); 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 proc *p = ndp->ni_cnd.cn_proc; struct ucred *cred; struct vattr vattr; struct vnode *vp; 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); if (!error) { /* update atime/mtime */ vattr_null(&vattr); getnanotime(&vattr.va_atime); vattr.va_mtime = vattr.va_atime; vattr.va_vaflags |= VA_UTIMES_NULL; (void)VOP_SETATTR(vp, &vattr, p->p_ucred, p); } crfree(cred); if (error) goto bad; vp->v_writecount++; return (0); bad: vput(vp); return (error); } void ptmattach(int n) { /* find the major and minor of the pty devices */ int i; for (i = 0; i < nchrdev; i++) if (cdevsw[i].d_open == ptsopen) break; if (i == nchrdev) panic("ptmattach: Can't find pty slave in cdevsw"); pts_major = i; } int ptmopen(dev_t dev, int flag, int mode, struct proc *p) { return(0); } int ptmclose(dev_t dev, int flag, int mode, struct proc *p) { return (0); } int ptmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p) { dev_t newdev; struct pt_softc * pti; struct nameidata cnd, snd; struct filedesc *fdp = p->p_fd; struct file *cfp = NULL, *sfp = NULL; int cindx, sindx, error; uid_t uid; gid_t gid; struct vattr vattr; struct ucred *cred; struct ptmget *ptm = (struct ptmget *)data; switch (cmd) { case PTMGET: fdplock(fdp); /* Grab two filedescriptors. */ if ((error = falloc(p, &cfp, &cindx)) != 0) { fdpunlock(fdp); break; } if ((error = falloc(p, &sfp, &sindx)) != 0) { fdremove(fdp, cindx); fdpunlock(fdp); closef(cfp, p); break; } fdpunlock(fdp); retry: /* Find and open a free master pty. */ newdev = pty_getfree(); if ((error = check_pty(newdev))) goto bad; pti = pt_softc[minor(newdev)]; NDINIT(&cnd, LOOKUP, NOFOLLOW|LOCKLEAF|KERNELPATH, UIO_SYSSPACE, pti->pty_pn, p); cnd.ni_pledge = PLEDGE_RPATH | PLEDGE_WPATH; if ((error = ptm_vn_open(&cnd)) != 0) { /* * Check if the master open failed because we lost * the race to grab it. */ if (error == EIO && !pty_isfree(minor(newdev))) goto retry; goto bad; } cfp->f_flag = FREAD|FWRITE; cfp->f_type = DTYPE_VNODE; cfp->f_ops = &vnops; cfp->f_data = (caddr_t) cnd.ni_vp; VOP_UNLOCK(cnd.ni_vp); /* * 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(&snd, LOOKUP, NOFOLLOW|LOCKLEAF|KERNELPATH, UIO_SYSSPACE, pti->pty_sn, p); snd.ni_pledge = PLEDGE_RPATH | PLEDGE_WPATH; if ((error = namei(&snd)) != 0) goto bad; if ((snd.ni_vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { gid = tty_gid; /* get real uid */ uid = p->p_ucred->cr_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(snd.ni_vp, &vattr, cred, p); crfree(cred); if (error) { vput(snd.ni_vp); goto bad; } } VOP_UNLOCK(snd.ni_vp); if (snd.ni_vp->v_usecount > 1 || (snd.ni_vp->v_flag & (VALIASED))) VOP_REVOKE(snd.ni_vp, REVOKEALL); /* * The vnode is useless after the revoke, we need to * namei again. */ vrele(snd.ni_vp); NDINIT(&snd, LOOKUP, NOFOLLOW|LOCKLEAF|KERNELPATH, UIO_SYSSPACE, pti->pty_sn, p); snd.ni_pledge = PLEDGE_RPATH | PLEDGE_WPATH; /* now open it */ if ((error = ptm_vn_open(&snd)) != 0) goto bad; sfp->f_flag = FREAD|FWRITE; sfp->f_type = DTYPE_VNODE; sfp->f_ops = &vnops; sfp->f_data = (caddr_t) snd.ni_vp; VOP_UNLOCK(snd.ni_vp); /* now, put the indexen and names into struct ptmget */ ptm->cfd = cindx; ptm->sfd = sindx; memcpy(ptm->cn, pti->pty_pn, sizeof(pti->pty_pn)); memcpy(ptm->sn, pti->pty_sn, sizeof(pti->pty_sn)); /* insert files now that we've passed all errors */ fdplock(fdp); fdinsert(fdp, cindx, 0, cfp); fdinsert(fdp, sindx, 0, sfp); fdpunlock(fdp); FRELE(cfp, p); FRELE(sfp, p); break; default: error = EINVAL; break; } return (error); bad: fdplock(fdp); fdremove(fdp, cindx); fdremove(fdp, sindx); fdpunlock(fdp); closef(cfp, p); closef(sfp, p); return (error); }