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|
/* $OpenBSD: tty_pty.c,v 1.75 2016/01/14 09:44:08 sf 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/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/poll.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);
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 minor)
{
struct pt_softc *pti;
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);
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(minor(dev))))
return (error);
pti = pt_softc[minor(dev)];
if (!pti->pt_tty) {
tp = pti->pt_tty = ttymalloc(1000000);
} else
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) != 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, 0);
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 ((pr->ps_sigacts->ps_sigignore & sigmask(SIGTTIN)) ||
(p->p_sigmask & sigmask(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, 0);
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, 0);
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 == 0)
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(minor(dev))))
return (error);
pti = pt_softc[minor(dev)];
if (!pti->pt_tty) {
tp = pti->pt_tty = ttymalloc(1000000);
} else
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 = 0; /* 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 = uiomovei(&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(&tp->t_outq.c_cf, TTIPRI | PCATCH,
ttyin, 0);
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 = uiomovei(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 = uiomovei(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 = uiomovei(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;
}
(*linesw[tp->t_line].l_rint)(*cp++, tp);
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(&tp->t_rawq.c_cf, TTOPRI | PCATCH,
ttyout, 0);
if (error == 0)
goto again;
/* adjust for data copied in but not written */
uio->uio_resid += cc;
done:
if (bufcc)
explicit_bzero(buf, bufcc);
return (error);
}
int
ptcpoll(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, s;
if (!ISSET(tp->t_state, TS_ISOPEN) && ISSET(tp->t_state, TS_CARR_ON))
goto notopen;
if (events & (POLLIN | POLLRDNORM)) {
/*
* Need to protect access to t_outq
*/
s = spltty();
if ((tp->t_outq.c_cc && !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);
splx(s);
}
/* NOTE: POLLHUP and POLLOUT/POLLWRNORM are mutually exclusive */
if (!ISSET(tp->t_state, TS_CARR_ON)) {
revents |= POLLHUP;
} else if (events & (POLLOUT | POLLWRNORM)) {
if ((pti->pt_flags & PF_REMOTE) ?
(tp->t_canq.c_cc == 0) :
((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG(tp) - 2) ||
(tp->t_canq.c_cc == 0 && ISSET(tp->t_lflag, ICANON))))
revents |= events & (POLLOUT | POLLWRNORM);
}
if (events & (POLLPRI | POLLRDBAND)) {
/* 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))
revents |= events & (POLLPRI | POLLRDBAND);
}
if (revents == 0) {
notopen:
if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND))
selrecord(p, &pti->pt_selr);
if (events & (POLLOUT | POLLWRNORM))
selrecord(p, &pti->pt_selw);
}
return (revents);
}
void
filt_ptcrdetach(struct knote *kn)
{
struct pt_softc *pti = (struct pt_softc *)kn->kn_hook;
int s;
s = spltty();
SLIST_REMOVE(&pti->pt_selr.si_note, kn, knote, kn_selnext);
splx(s);
}
int
filt_ptcread(struct knote *kn, long hint)
{
struct pt_softc *pti = (struct pt_softc *)kn->kn_hook;
struct tty *tp;
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++;
}
return (kn->kn_data > 0);
}
void
filt_ptcwdetach(struct knote *kn)
{
struct pt_softc *pti = (struct pt_softc *)kn->kn_hook;
int s;
s = spltty();
SLIST_REMOVE(&pti->pt_selw.si_note, kn, knote, kn_selnext);
splx(s);
}
int
filt_ptcwrite(struct knote *kn, long hint)
{
struct pt_softc *pti = (struct pt_softc *)kn->kn_hook;
struct tty *tp;
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)
kn->kn_data = tp->t_canq.c_cn -
(tp->t_rawq.c_cc + tp->t_canq.c_cc);
}
return (kn->kn_data > 0);
}
struct filterops ptcread_filtops =
{ 1, NULL, filt_ptcrdetach, filt_ptcread };
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.si_note;
kn->kn_fop = &ptcread_filtops;
break;
case EVFILT_WRITE:
klist = &pti->pt_selw.si_note;
kn->kn_fop = &ptcwrite_filtops;
break;
default:
return (EINVAL);
}
kn->kn_hook = (caddr_t)pti;
s = spltty();
SLIST_INSERT_HEAD(klist, kn, kn_selnext);
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) {
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)
{
int error, oldmax;
if (namelen != 1)
return (ENOTDIR);
switch (name[0]) {
case KERN_TTY_MAXPTYS:
if (!newp)
return (sysctl_rdint(oldp, oldlenp, newp, maxptys));
rw_enter_write(&pt_softc_lock);
oldmax = maxptys;
error = sysctl_int(oldp, oldlenp, newp, newlen, &maxptys);
/*
* We can't set the max lower than the current active
* value or to a value bigger than NPTY_MAX.
*/
if (error == 0 && (maxptys > NPTY_MAX || maxptys < npty)) {
maxptys = oldmax;
error = ERANGE;
}
rw_exit_write(&pt_softc_lock);
return (error);
case KERN_TTY_NPTYS:
return (sysctl_rdint(oldp, oldlenp, newp, npty));
#ifdef notyet
case KERN_TTY_GID:
return (sysctl_int(oldp, oldlenp, newp, newlen, &tty_gid));
#endif
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, error;
struct pt_softc * pti;
struct nameidata cnd, snd;
struct filedesc *fdp = p->p_fd;
struct file *cfp = NULL, *sfp = NULL;
int cindx, sindx;
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);
closef(cfp, p);
fdpunlock(fdp);
break;
}
retry:
/* Find and open a free master pty. */
newdev = pty_getfree();
if ((error = check_pty(minor(newdev))))
goto bad;
pti = pt_softc[minor(newdev)];
NDINIT(&cnd, LOOKUP, NOFOLLOW|LOCKLEAF, 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, 0, p);
/*
* 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, 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, 0, p);
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, 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, 0, p);
/* 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));
/* mark the files mature now that we've passed all errors */
FILE_SET_MATURE(cfp, p);
FILE_SET_MATURE(sfp, p);
fdpunlock(fdp);
break;
default:
error = EINVAL;
break;
}
return (error);
bad:
fdremove(fdp, cindx);
closef(cfp, p);
fdremove(fdp, sindx);
closef(sfp, p);
fdpunlock(fdp);
return (error);
}
|