gems-kernel/source/THIRDPARTY/xnu/bsd/kern/tty_dev.c
2024-06-03 11:29:39 -05:00

1214 lines
29 KiB
C

/*
* Copyright (c) 1997-2020 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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
*/
/* Common callbacks for the pseudo-teletype driver (pty/tty)
* and cloning pseudo-teletype driver (ptmx/pts).
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/tty.h>
#include <sys/conf.h>
#include <sys/file_internal.h>
#include <sys/uio_internal.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/vnode_internal.h> /* _devfs_setattr() */
#include <sys/stat.h> /* _devfs_setattr() */
#include <sys/user.h>
#include <sys/signalvar.h>
#include <sys/sysctl.h>
#include <miscfs/devfs/devfs.h>
#include <miscfs/devfs/devfsdefs.h> /* DEVFS_LOCK()/DEVFS_UNLOCK() */
#include <dev/kmreg_com.h>
#include <machine/cons.h>
#if CONFIG_MACF
#include <security/mac_framework.h>
#endif
#include "tty_dev.h"
/* XXX belongs in devfs somewhere - LATER */
static int _devfs_setattr(void *, unsigned short, uid_t, gid_t);
/*
* Forward declarations
*/
static void ptcwakeup(struct tty *tp, int flag);
__XNU_PRIVATE_EXTERN d_open_t ptsopen;
__XNU_PRIVATE_EXTERN d_close_t ptsclose;
__XNU_PRIVATE_EXTERN d_read_t ptsread;
__XNU_PRIVATE_EXTERN d_write_t ptswrite;
__XNU_PRIVATE_EXTERN d_ioctl_t ptyioctl; /* common ioctl */
__XNU_PRIVATE_EXTERN d_stop_t ptsstop;
__XNU_PRIVATE_EXTERN d_reset_t ptsreset;
__XNU_PRIVATE_EXTERN d_select_t ptsselect;
__XNU_PRIVATE_EXTERN d_open_t ptcopen;
__XNU_PRIVATE_EXTERN d_close_t ptcclose;
__XNU_PRIVATE_EXTERN d_read_t ptcread;
__XNU_PRIVATE_EXTERN d_write_t ptcwrite;
__XNU_PRIVATE_EXTERN d_stop_t ptcstop; /* NO-OP */
__XNU_PRIVATE_EXTERN d_reset_t ptcreset;
__XNU_PRIVATE_EXTERN d_select_t ptcselect;
/*
* XXX Should be devfs function... and use VATTR mechanisms, per
* XXX vnode_setattr2(); only we maybe can't really get back to the
* XXX vnode here for cloning devices (but it works for *cloned* devices
* XXX that are not themselves cloning).
*
* Returns: 0 Success
* namei:???
* vnode_setattr:???
*/
static int
_devfs_setattr(void * handle, unsigned short mode, uid_t uid, gid_t gid)
{
devdirent_t *direntp = (devdirent_t *)handle;
devnode_t *devnodep;
int error = EACCES;
vfs_context_t ctx = vfs_context_current();
struct vnode_attr va;
VATTR_INIT(&va);
VATTR_SET(&va, va_uid, uid);
VATTR_SET(&va, va_gid, gid);
VATTR_SET(&va, va_mode, mode & ALLPERMS);
/*
* If the TIOCPTYGRANT loses the race with the clone operation because
* this function is not part of devfs, and therefore can't take the
* devfs lock to protect the direntp update, then force user space to
* redrive the grant request.
*/
if (direntp == NULL || (devnodep = direntp->de_dnp) == NULL) {
error = ERESTART;
goto out;
}
/*
* Only do this if we are operating on device that doesn't clone
* each time it's referenced. We perform a lookup on the device
* to insure we get the right instance. We can't just use the call
* to devfs_dntovn() to get the vp for the operation, because
* dn_dvm may not have been initialized.
*/
if (devnodep->dn_clone == NULL) {
struct nameidata nd;
char name[128];
snprintf(name, sizeof(name), "/dev/%s", direntp->de_name);
NDINIT(&nd, LOOKUP, OP_SETATTR, FOLLOW, UIO_SYSSPACE, CAST_USER_ADDR_T(name), ctx);
error = namei(&nd);
if (error) {
goto out;
}
error = vnode_setattr(nd.ni_vp, &va, ctx);
vnode_put(nd.ni_vp);
nameidone(&nd);
goto out;
}
out:
return error;
}
#define BUFSIZ 100 /* Chunk size iomoved to/from user */
static struct tty_dev_t *tty_dev_head;
__private_extern__ void
tty_dev_register(struct tty_dev_t *driver)
{
if (driver) {
driver->next = tty_dev_head;
tty_dev_head = driver;
}
}
/*
* Given a minor number, return the corresponding structure for that minor
* number. If there isn't one, and the create flag is specified, we create
* one if possible.
*
* Parameters: minor Minor number of ptmx device
* open_flag PF_OPEN_M First open of primary
* PF_OPEN_S First open of replica
* 0 Just want ioctl struct
*
* Returns: NULL Did not exist/could not create
* !NULL structure corresponding minor number
*
* Locks: tty_lock() on ptmx_ioctl->pt_tty NOT held on entry or exit.
*/
static struct tty_dev_t *
pty_get_driver(dev_t dev)
{
int major = major(dev);
struct tty_dev_t *driver;
for (driver = tty_dev_head; driver != NULL; driver = driver->next) {
if ((driver->primary == major || driver->replica == major)) {
break;
}
}
return driver;
}
static struct ptmx_ioctl *
pty_get_ioctl(dev_t dev, int open_flag, struct tty_dev_t **out_driver)
{
struct tty_dev_t *driver = pty_get_driver(dev);
if (out_driver) {
*out_driver = driver;
}
if (driver && driver->open) {
return driver->open(minor(dev), open_flag);
}
return NULL;
}
/*
* Locks: tty_lock() of old_ptmx_ioctl->pt_tty NOT held for this call.
*/
static int
pty_free_ioctl(dev_t dev, int open_flag)
{
struct tty_dev_t *driver = pty_get_driver(dev);
if (driver && driver->free) {
return driver->free(minor(dev), open_flag);
}
return 0;
}
static int
pty_get_name(dev_t dev, char *buffer, size_t size)
{
struct tty_dev_t *driver = pty_get_driver(dev);
if (driver && driver->name) {
return driver->name(minor(dev), buffer, size);
}
return 0;
}
__private_extern__ int
ptsopen(dev_t dev, int flag, __unused int devtype, __unused struct proc *p)
{
int error;
struct tty_dev_t *driver;
bool free_ptmx_ioctl = true;
struct ptmx_ioctl *pti = pty_get_ioctl(dev, PF_OPEN_S, &driver);
if (pti == NULL) {
return ENXIO;
}
if (!(pti->pt_flags & PF_UNLOCKED)) {
error = EAGAIN;
goto out_free;
}
struct tty *tp = pti->pt_tty;
tty_lock(tp);
if ((tp->t_state & TS_ISOPEN) == 0) {
termioschars(&tp->t_termios); /* 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 ((tp->t_state & TS_XCLUDE) && kauth_cred_issuser(kauth_cred_get())) {
error = EBUSY;
goto out_unlock;
}
if (tp->t_oproc) { /* Ctrlr still around. */
(void)(*linesw[tp->t_line].l_modem)(tp, 1);
}
while ((tp->t_state & TS_CARR_ON) == 0) {
if (flag & FNONBLOCK) {
break;
}
error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH, __FUNCTION__, 0);
if (error) {
goto out_unlock;
}
}
error = (*linesw[tp->t_line].l_open)(dev, tp);
/* Successful open; mark as open by the replica */
free_ptmx_ioctl = false;
CLR(tp->t_state, TS_IOCTL_NOT_OK);
if (error == 0) {
ptcwakeup(tp, FREAD | FWRITE);
}
out_unlock:
tty_unlock(tp);
out_free:
if (free_ptmx_ioctl) {
pty_free_ioctl(dev, PF_OPEN_S);
}
return error;
}
__private_extern__ int
ptsclose(dev_t dev, int flag, __unused int mode, __unused proc_t p)
{
int err;
/*
* This is temporary until the VSX conformance tests
* are fixed. They are hanging with a deadlock
* where close() will not complete without t_timeout set
*/
#define FIX_VSX_HANG 1
#ifdef FIX_VSX_HANG
int save_timeout;
#endif
struct tty_dev_t *driver;
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, &driver);
struct tty *tp;
if (pti == NULL) {
return ENXIO;
}
tp = pti->pt_tty;
tty_lock(tp);
#ifdef FIX_VSX_HANG
save_timeout = tp->t_timeout;
tp->t_timeout = 60;
#endif
/*
* Close the line discipline and backing TTY structures.
*/
err = (*linesw[tp->t_line].l_close)(tp, flag);
(void)ttyclose(tp);
/*
* Flush data and notify any waiters on the primary side of this PTY.
*/
ptsstop(tp, FREAD | FWRITE);
#ifdef FIX_VSX_HANG
tp->t_timeout = save_timeout;
#endif
tty_unlock(tp);
if ((flag & IO_REVOKE) == IO_REVOKE && driver->revoke) {
driver->revoke(minor(dev), tp);
}
/* unconditional, just like ttyclose() */
pty_free_ioctl(dev, PF_OPEN_S);
return err;
}
__private_extern__ int
ptsread(dev_t dev, struct uio *uio, int flag)
{
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, NULL);
struct tty *tp;
int error = 0;
struct uthread *ut;
if (pti == NULL) {
return ENXIO;
}
tp = pti->pt_tty;
tty_lock(tp);
ut = current_uthread();
if (tp->t_oproc) {
error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
}
ptcwakeup(tp, FWRITE);
tty_unlock(tp);
return error;
}
/*
* Write to pseudo-tty.
* Wakeups of controlling tty will happen
* indirectly, when tty driver calls ptsstart.
*/
__private_extern__ int
ptswrite(dev_t dev, struct uio *uio, int flag)
{
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, NULL);
struct tty *tp;
int error;
if (pti == NULL) {
return ENXIO;
}
tp = pti->pt_tty;
tty_lock(tp);
if (tp->t_oproc == 0) {
error = EIO;
} else {
error = (*linesw[tp->t_line].l_write)(tp, uio, flag);
}
tty_unlock(tp);
return error;
}
/*
* Start output on pseudo-tty.
* Wake up process selecting or sleeping for input from controlling tty.
*
* t_oproc for this driver; called from within the line discipline
*
* Locks: Assumes tp is locked on entry, remains locked on exit
*/
static void
ptsstart(struct tty *tp)
{
struct ptmx_ioctl *pti = pty_get_ioctl(tp->t_dev, 0, NULL);
if (pti == NULL) {
goto out;
}
if (tp->t_state & TS_TTSTOP) {
goto out;
}
if (pti->pt_flags & PF_STOPPED) {
pti->pt_flags &= ~PF_STOPPED;
pti->pt_send = TIOCPKT_START;
}
ptcwakeup(tp, FREAD);
out:
return;
}
static void
ptcwakeup_knote(struct selinfo *sip, long hint)
{
if ((sip->si_flags & SI_KNPOSTING) == 0) {
sip->si_flags |= SI_KNPOSTING;
KNOTE(&sip->si_note, hint);
sip->si_flags &= ~SI_KNPOSTING;
}
}
/*
* Locks: Assumes tty_lock() is held over this call.
*/
static void
ptcwakeup(struct tty *tp, int flag)
{
struct ptmx_ioctl *pti = pty_get_ioctl(tp->t_dev, 0, NULL);
if (pti == NULL) {
return;
}
if (flag & FREAD) {
selwakeup(&pti->pt_selr);
wakeup(TSA_PTC_READ(tp));
ptcwakeup_knote(&pti->pt_selr, 1);
}
if (flag & FWRITE) {
selwakeup(&pti->pt_selw);
wakeup(TSA_PTC_WRITE(tp));
ptcwakeup_knote(&pti->pt_selw, 1);
}
}
__private_extern__ int
ptcopen(dev_t dev, __unused int flag, __unused int devtype, __unused proc_t p)
{
struct tty_dev_t *driver;
struct ptmx_ioctl *pti = pty_get_ioctl(dev, PF_OPEN_M, &driver);
if (pti == NULL) {
return ENXIO;
} else if (pti == (struct ptmx_ioctl*)-1) {
return EREDRIVEOPEN;
}
struct tty *tp = pti->pt_tty;
tty_lock(tp);
/* If primary is open OR replica is still draining, pty is still busy */
if (tp->t_oproc || (tp->t_state & TS_ISOPEN)) {
tty_unlock(tp);
/*
* If primary is closed, we are the only reference, so we
* need to clear the primary open bit
*/
if (!tp->t_oproc) {
pty_free_ioctl(dev, PF_OPEN_M);
}
return EBUSY;
}
tp->t_oproc = ptsstart;
CLR(tp->t_state, TS_ZOMBIE);
SET(tp->t_state, TS_IOCTL_NOT_OK);
#ifdef sun4c
tp->t_stop = ptsstop;
#endif
(void)(*linesw[tp->t_line].l_modem)(tp, 1);
tp->t_lflag &= ~EXTPROC;
if (driver->open_reset) {
pti->pt_flags = PF_UNLOCKED;
pti->pt_send = 0;
pti->pt_ucntl = 0;
}
tty_unlock(tp);
return 0;
}
__private_extern__ int
ptcclose(dev_t dev, __unused int flags, __unused int fmt, __unused proc_t p)
{
struct tty_dev_t *driver;
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, &driver);
struct tty *tp;
struct tty *constty = NULL;
struct tty *freetp = NULL;
if (!pti) {
return ENXIO;
}
tp = pti->pt_tty;
tty_lock(tp);
constty = copy_constty();
if (constty == tp) {
freetp = set_constty(NULL);
if (freetp != NULL) {
if (freetp == tp) {
ttyfree_locked(freetp);
} else {
ttyfree(freetp);
}
freetp = NULL;
}
/*
* Closing current console tty; disable printing of console
* messages at bottom-level driver.
*/
(*cdevsw[major(tp->t_dev)].d_ioctl)
(tp->t_dev, KMIOCDISABLCONS, NULL, 0, current_proc());
}
if (constty != NULL) {
if (constty == tp) {
ttyfree_locked(constty);
} else {
ttyfree(constty);
}
constty = NULL;
}
/*
* XXX MDMBUF makes no sense for PTYs, but would inhibit an `l_modem`.
* CLOCAL makes sense but isn't supported. Special `l_modem`s that ignore
* carrier drop make no sense for PTYs but may be in use because other parts
* of the line discipline make sense for PTYs. Recover by doing everything
* that a normal `ttymodem` would have done except for sending SIGHUP.
*/
(void)(*linesw[tp->t_line].l_modem)(tp, 0);
if (tp->t_state & TS_ISOPEN) {
tp->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
tp->t_state |= TS_ZOMBIE;
ttyflush(tp, FREAD | FWRITE);
}
/*
* Null out the backing TTY struct's open procedure to prevent starting
* replicas through `ptsstart`.
*/
tp->t_oproc = NULL;
/*
* Clear any select or kevent waiters under the lock.
*/
knote(&pti->pt_selr.si_note, NOTE_REVOKE, true);
selthreadclear(&pti->pt_selr);
knote(&pti->pt_selw.si_note, NOTE_REVOKE, true);
selthreadclear(&pti->pt_selw);
tty_unlock(tp);
pty_free_ioctl(dev, PF_OPEN_M);
#if CONFIG_MACF
if (driver->mac_notify) {
mac_pty_notify_close(p, tp, dev, NULL);
}
#endif
return 0;
}
__private_extern__ int
ptcread(dev_t dev, struct uio *uio, int flag)
{
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, NULL);
struct tty *tp;
char buf[BUFSIZ];
int error = 0, cc;
if (pti == NULL) {
return ENXIO;
}
tp = pti->pt_tty;
tty_lock(tp);
/*
* We want to block until the replica
* is open, and there's something to read;
* but if we lost the replica 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) {
goto out;
}
if (pti->pt_send & TIOCPKT_IOCTL) {
#ifdef __LP64__
if (uio->uio_segflg == UIO_USERSPACE32) {
static struct termios32 tio32;
cc = MIN((int)uio_resid(uio), (int)sizeof(tio32));
termios64to32((struct user_termios *)&tp->t_termios,
(struct termios32 *)&tio32);
uiomove((caddr_t)&tio32, cc, uio);
#else
if (uio->uio_segflg == UIO_USERSPACE64) {
static struct user_termios tio64;
cc = MIN((int)uio_resid(uio), (int)sizeof(tio64));
termios32to64((struct termios32 *)&tp->t_termios,
(struct user_termios *)&tio64);
uiomove((caddr_t)&tio64, cc, uio);
#endif
} else {
cc = MIN((int)uio_resid(uio), (int)sizeof(tp->t_termios));
uiomove((caddr_t)&tp->t_termios, cc, uio);
}
}
pti->pt_send = 0;
goto out;
}
if (pti->pt_flags & PF_UCNTL && pti->pt_ucntl) {
error = ureadc((int)pti->pt_ucntl, uio);
if (error) {
goto out;
}
pti->pt_ucntl = 0;
goto out;
}
if (tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) {
break;
}
}
if ((tp->t_state & TS_CONNECTED) == 0) {
goto out; /* EOF */
}
if (flag & IO_NDELAY) {
error = EWOULDBLOCK;
goto out;
}
error = ttysleep(tp, TSA_PTC_READ(tp), TTIPRI | PCATCH, __FUNCTION__, 0);
if (error) {
goto out;
}
}
if (pti->pt_flags & (PF_PKT | PF_UCNTL)) {
error = ureadc(0, uio);
}
while (uio_resid(uio) > 0 && error == 0) {
cc = q_to_b(&tp->t_outq, (u_char *)buf, MIN((int)uio_resid(uio), BUFSIZ));
if (cc <= 0) {
break;
}
error = uiomove(buf, cc, uio);
}
(*linesw[tp->t_line].l_start)(tp);
out:
tty_unlock(tp);
return error;
}
/*
* Line discipline callback
*
* Locks: tty_lock() is assumed held on entry and exit.
*/
__private_extern__ int
ptsstop(struct tty* tp, int flush)
{
struct ptmx_ioctl *pti = pty_get_ioctl(tp->t_dev, 0, NULL);
int flag;
if (pti == NULL) {
return ENXIO;
}
/* 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;
}
__private_extern__ int
ptsreset(__unused int uban)
{
return 0;
}
int
ptsselect(dev_t dev, int rw, void *wql, proc_t p)
{
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, NULL);
struct tty *tp;
int retval = 0;
if (pti == NULL) {
return ENXIO;
}
tp = pti->pt_tty;
if (tp == NULL) {
return ENXIO;
}
tty_lock(tp);
switch (rw) {
case FREAD:
if (ISSET(tp->t_state, TS_ZOMBIE)) {
retval = 1;
break;
}
retval = ttnread(tp);
if (retval > 0) {
break;
}
selrecord(p, &tp->t_rsel, wql);
break;
case FWRITE:
if (ISSET(tp->t_state, TS_ZOMBIE)) {
retval = 1;
break;
}
if ((tp->t_outq.c_cc <= tp->t_lowat) &&
ISSET(tp->t_state, TS_CONNECTED)) {
retval = tp->t_hiwat - tp->t_outq.c_cc;
break;
}
selrecord(p, &tp->t_wsel, wql);
break;
}
tty_unlock(tp);
return retval;
}
__private_extern__ int
ptcselect(dev_t dev, int rw, void *wql, proc_t p)
{
struct tty_dev_t *driver;
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, &driver);
struct tty *tp;
int retval = 0;
if (pti == NULL) {
return ENXIO;
}
tp = pti->pt_tty;
tty_lock(tp);
if ((tp->t_state & TS_CONNECTED) == 0) {
retval = 1;
goto out;
}
switch (rw) {
case FREAD:
/*
* Need to block timeouts (ttrstart).
*/
if ((tp->t_state & TS_ISOPEN) &&
tp->t_outq.c_cc && (tp->t_state & TS_TTSTOP) == 0) {
retval = (driver->fix_7828447) ? tp->t_outq.c_cc : 1;
break;
}
OS_FALLTHROUGH;
case 0: /* exceptional */
if ((tp->t_state & TS_ISOPEN) &&
(((pti->pt_flags & PF_PKT) && pti->pt_send) ||
((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))) {
retval = 1;
break;
}
selrecord(p, &pti->pt_selr, wql);
break;
case FWRITE:
if (tp->t_state & TS_ISOPEN) {
retval = (TTYHOG - 2) - (tp->t_rawq.c_cc + tp->t_canq.c_cc);
if (retval > 0) {
retval = (driver->fix_7828447) ? retval : 1;
break;
}
if (tp->t_canq.c_cc == 0 && (tp->t_lflag & ICANON)) {
retval = 1;
break;
}
retval = 0;
}
selrecord(p, &pti->pt_selw, wql);
break;
}
out:
tty_unlock(tp);
return retval;
}
__private_extern__ int
ptcstop(__unused struct tty *tp, __unused int flush)
{
return 0;
}
__private_extern__ int
ptcreset(__unused int uban)
{
return 0;
}
__private_extern__ int
ptcwrite(dev_t dev, struct uio *uio, int flag)
{
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, NULL);
struct tty *tp;
u_char *cp = NULL;
int cc = 0;
u_char locbuf[BUFSIZ];
int wcnt = 0;
int error = 0;
if (pti == NULL) {
return ENXIO;
}
tp = pti->pt_tty;
tty_lock(tp);
again:
if ((tp->t_state & TS_ISOPEN) == 0) {
goto block;
}
while (uio_resid(uio) > 0 || cc > 0) {
if (cc == 0) {
cc = MIN((int)uio_resid(uio), BUFSIZ);
cp = locbuf;
error = uiomove((caddr_t)cp, cc, uio);
if (error) {
goto out;
}
/* check again for safety */
if ((tp->t_state & TS_ISOPEN) == 0) {
/* adjust for data copied in but not written */
uio_setresid(uio, (uio_resid(uio) + cc));
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 || !(tp->t_lflag & ICANON))) {
wakeup(TSA_HUP_OR_INPUT(tp));
goto block;
}
OS_ANALYZER_SUPPRESS("80961525") (*linesw[tp->t_line].l_rint)(*cp++, tp);
wcnt++;
cc--;
}
cc = 0;
}
out:
tty_unlock(tp);
return error;
block:
/*
* Come here to wait for replica to open, for space
* in outq, or space in rawq, or an empty canq.
*/
if ((tp->t_state & TS_CONNECTED) == 0) {
/* adjust for data copied in but not written */
uio_setresid(uio, (uio_resid(uio) + cc));
error = EIO;
goto out;
}
if (flag & IO_NDELAY) {
/* adjust for data copied in but not written */
uio_setresid(uio, (uio_resid(uio) + cc));
if (wcnt == 0) {
error = EWOULDBLOCK;
}
goto out;
}
error = ttysleep(tp, TSA_PTC_WRITE(tp), TTOPRI | PCATCH, __FUNCTION__, 0);
if (error) {
/* adjust for data copied in but not written */
uio_setresid(uio, (uio_resid(uio) + cc));
goto out;
}
goto again;
}
/*
* ptyioctl: Assumes dev was opened and lock was initilized
*/
__private_extern__ int
ptyioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
struct tty_dev_t *driver;
struct ptmx_ioctl *pti = pty_get_ioctl(dev, 0, &driver);
struct tty *tp;
int stop, error = 0;
int allow_ext_ioctl = 1;
if (pti == NULL || pti->pt_tty == NULL) {
return ENXIO;
}
if (cmd == KMIOCDISABLCONS) {
return 0;
}
tp = pti->pt_tty;
tty_lock(tp);
u_char *cc = tp->t_cc;
/*
* Do not permit extended ioctls on the primary side of the pty unless
* the replica side has been successfully opened and initialized.
*/
if (major(dev) == driver->primary &&
driver->fix_7070978 &&
ISSET(tp->t_state, TS_IOCTL_NOT_OK)) {
allow_ext_ioctl = 0;
}
/*
* IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG.
* ttywflush(tp) will hang if there are characters in the outq.
*/
if (cmd == TIOCEXT && allow_ext_ioctl) {
/*
* 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;
}
goto out;
} else if (cdevsw[major(dev)].d_open == ptcopen) {
switch (cmd) {
case TIOCGPGRP:
/*
* We aviod 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;
goto out;
case TIOCPKT:
if (*(int *)data) {
if (pti->pt_flags & PF_UCNTL) {
error = EINVAL;
goto out;
}
pti->pt_flags |= PF_PKT;
} else {
pti->pt_flags &= ~PF_PKT;
}
goto out;
case TIOCUCNTL:
if (*(int *)data) {
if (pti->pt_flags & PF_PKT) {
error = EINVAL;
goto out;
}
pti->pt_flags |= PF_UCNTL;
} else {
pti->pt_flags &= ~PF_UCNTL;
}
goto out;
case TIOCSETP:
case TIOCSETN:
case TIOCSETD:
case TIOCSETA_32:
case TIOCSETAW_32:
case TIOCSETAF_32:
case TIOCSETA_64:
case TIOCSETAW_64:
case TIOCSETAF_64:
ndflush(&tp->t_outq, tp->t_outq.c_cc);
break;
case TIOCSIG:
if (*(unsigned int *)data >= NSIG ||
*(unsigned int *)data == 0) {
error = EINVAL;
goto out;
}
if ((tp->t_lflag & NOFLSH) == 0) {
ttyflush(tp, FREAD | FWRITE);
}
if ((*(unsigned int *)data == SIGINFO) &&
((tp->t_lflag & NOKERNINFO) == 0)) {
ttyinfo_locked(tp);
}
/*
* SAFE: All callers drop the lock on return and
* SAFE: the linesw[] will short circut this call
* SAFE: if the ioctl() is eaten before the lower
* SAFE: level code gets to see it.
*/
tty_pgsignal_locked(tp, *(unsigned int *)data, 1);
goto out;
case TIOCPTYGRANT: /* grantpt(3) */
/*
* Change the uid of the replica to that of the calling
* thread, change the gid of the replica to GID_TTY,
* change the mode to 0620 (rw--w----).
*/
{
error = _devfs_setattr(pti->pt_devhandle, 0620, kauth_getuid(), GID_TTY);
if (major(dev) == driver->primary) {
if (driver->mac_notify) {
#if CONFIG_MACF
if (!error) {
tty_unlock(tp);
mac_pty_notify_grant(p, tp, dev, NULL);
tty_lock(tp);
}
#endif
} else {
error = 0;
}
}
goto out;
}
case TIOCPTYGNAME: /* ptsname(3) */
/*
* Report the name of the replica device in *data
* (128 bytes max.). Use the same template string
* used for calling devfs_make_node() to create it.
*/
pty_get_name(dev, data, 128);
error = 0;
goto out;
case TIOCPTYUNLK: /* unlockpt(3) */
/*
* Unlock the replica device so that it can be opened.
*/
if (major(dev) == driver->primary) {
pti->pt_flags |= PF_UNLOCKED;
}
error = 0;
goto out;
}
/*
* Fail all other calls; pty primaries are not serial devices;
* we only pretend they are when the replica side of the pty is
* already open.
*/
if (!allow_ext_ioctl) {
error = ENOTTY;
goto out;
}
}
error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
if (error == ENOTTY) {
error = ttioctl_locked(tp, cmd, data, flag, p);
if (error == ENOTTY) {
if (pti->pt_flags & PF_UCNTL && (cmd & ~0xff) == UIOCCMD(0)) {
/* Process the UIOCMD ioctl group */
if (cmd & 0xff) {
pti->pt_ucntl = (u_char)cmd;
ptcwakeup(tp, FREAD);
}
error = 0;
goto out;
} else if (cmd == TIOCSBRK || cmd == TIOCCBRK) {
/*
* POSIX conformance; rdar://3936338
*
* Clear ENOTTY in the case of setting or
* clearing a break failing because pty's
* don't support break like real serial
* ports.
*/
error = 0;
goto out;
}
}
}
/*
* If external processing and packet mode send ioctl packet.
*/
if ((tp->t_lflag & EXTPROC) && (pti->pt_flags & PF_PKT)) {
switch (cmd) {
case TIOCSETA_32:
case TIOCSETAW_32:
case TIOCSETAF_32:
case TIOCSETA_64:
case TIOCSETAW_64:
case TIOCSETAF_64:
case TIOCSETP:
case TIOCSETN:
case TIOCSETC:
case TIOCSLTC:
case TIOCLBIS:
case TIOCLBIC:
case TIOCLSET:
pti->pt_send |= TIOCPKT_IOCTL;
ptcwakeup(tp, FREAD);
break;
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);
}
}
out:
tty_unlock(tp);
return error;
}