/*-
* Copyright (c) 2008, 2020 The NetBSD Foundation, Inc.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*-
* Copyright (c) 1982, 1986, 1990, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.c 8.13 (Berkeley) 1/9/95
*/
/*
* Used to determine whether we still have a connection. This is true in
* one of 3 cases:
* 1) We have carrier.
* 2) It's a locally attached terminal, and we are therefore ignoring carrier.
* 3) We're using a flow control mechanism that overloads the carrier signal.
*/
#define CONNECTED(tp) (ISSET(tp->t_state, TS_CARR_ON) || \
ISSET(tp->t_cflag, CLOCAL | MDMBUF))
/*
* Table with character classes and parity. The 8th bit indicates parity,
* the 7th bit indicates the character is an alphameric or underscore (for
* ALTWERASE), and the low 6 bits indicate delay type. If the low 6 bits
* are 0 then the character needs no special processing on output; classes
* other than 0 might be translated or (not currently) require delays.
*/
#define E 0x00 /* Even parity. */
#define O 0x80 /* Odd parity. */
#define PARITY(c) (char_type[c] & O)
/*
* ttylock(tp), ttyunlock(tp), ttylocked(tp)
*
* Exclusive lock on tty. Currently a single global lock.
*
* ttylocked is for positive DIAGNOSTIC assertions only.
*/
void
ttylock(struct tty *tp)
{
mutex_spin_enter(&tty_lock);
}
void
ttyunlock(struct tty *tp)
{
mutex_spin_exit(&tty_lock);
}
bool
ttylocked(struct tty *tp)
{
return mutex_owned(&tty_lock);
}
int
ttyopen(struct tty *tp, int dialout, int nonblock)
{
int error;
error = 0;
mutex_spin_enter(&tty_lock);
if (dialout) {
/*
* If the device is already open for non-dialout, fail.
* Otherwise, set TS_DIALOUT to block any pending non-dialout
* opens.
*/
if (ISSET(tp->t_state, TS_ISOPEN) &&
!ISSET(tp->t_state, TS_DIALOUT)) {
error = EBUSY;
goto out;
}
SET(tp->t_state, TS_DIALOUT);
} else {
if (!nonblock) {
/*
* Wait for carrier. Also wait for any dialout
* processes to close the tty first.
*/
while (ISSET(tp->t_state, TS_DIALOUT) ||
!CONNECTED(tp)) {
tp->t_wopen++;
error = ttysleep(tp, &tp->t_rawcv, true, 0);
tp->t_wopen--;
if (error)
goto out;
}
} else {
/*
* Don't allow a non-blocking non-dialout open if the
* device is already open for dialout.
*/
if (ISSET(tp->t_state, TS_DIALOUT)) {
error = EBUSY;
goto out;
}
}
}
/*
* Interrupt any pending I/O and make it fail. Used before close to
* interrupt pending open/read/write/&c. and make it fail promptly.
*/
void
ttycancel(struct tty *tp)
{
/*
* Handle close() on a tty line: flush and set to initial state,
* bumping generation number so that pending read/write calls
* can detect recycling of the tty.
*/
int
ttyclose(struct tty *tp)
{
struct session *sess;
/*
* Make sure this is not the constty. Without constty_lock it
* is always allowed to transition from nonnull to null.
*/
(void)atomic_cas_ptr(&constty, tp, NULL);
/*
* We don't know if this has _ever_ been the constty: another
* thread may have kicked it out as constty before we started
* to close.
*
* So we wait for all users that might be acquiring references
* to finish doing so -- after that, no more references can be
* made, at which point we can safely flush the tty, wait for
* the existing references to drain, and finally free or reuse
* the tty.
*/
pserialize_perform(constty_psz);
/*
* tty_acquire(tp), tty_release(tp)
*
* Acquire a reference to tp that prevents it from being closed
* until released. Caller must guarantee tp has not yet been
* closed, e.g. by obtaining tp from constty during a pserialize
* read section. Caller must not hold tty_lock.
*/
void
tty_acquire(struct tty *tp)
{
unsigned refcnt __diagused;
do {
old = atomic_load_relaxed(&tp->t_refcnt);
if (old == 1) {
mutex_spin_enter(&tty_lock);
if (atomic_dec_uint_nv(&tp->t_refcnt) == 0)
cv_broadcast(&ttyref_cv);
mutex_spin_exit(&tty_lock);
return;
}
KASSERT(old != 0);
new = old - 1;
} while (atomic_cas_uint(&tp->t_refcnt, old, new) != old);
}
/*
* This macro is used in canonical mode input processing, where a read
* request shall not return unless a 'line delimiter' ('\n') or 'break'
* (EOF, EOL, EOL2) character (or a signal) has been received. As EOL2
* is an extension to the POSIX.1 defined set of special characters,
* recognize it only if IEXTEN is set in the set of local flags.
*/
#define TTBREAKC(c, lflg) \
((c) == '\n' || (((c) == cc[VEOF] || (c) == cc[VEOL] || \
((c) == cc[VEOL2] && ISSET(lflg, IEXTEN))) && (c) != _POSIX_VDISABLE))
/*
* ttyinput() helper.
* Call with the tty lock held.
*/
/* XXX static */ int
ttyinput_wlock(int c, struct tty *tp)
{
int iflag, lflag, i, error;
u_char *cc;
KASSERT(mutex_owned(&tty_lock));
/*
* If input is pending take it first.
*/
lflag = tp->t_lflag;
if (ISSET(lflag, PENDIN))
ttypend(tp);
/*
* Gather stats.
*/
if (ISSET(lflag, ICANON)) {
++tk_cancc;
++tp->t_cancc;
} else {
++tk_rawcc;
++tp->t_rawcc;
}
++tk_nin;
cc = tp->t_cc;
/*
* Handle exceptional conditions (break, parity, framing).
*/
iflag = tp->t_iflag;
if ((error = (ISSET(c, TTY_ERRORMASK))) != 0) {
CLR(c, TTY_ERRORMASK);
if (ISSET(error, TTY_FE) && c == 0) { /* Break. */
if (ISSET(iflag, IGNBRK))
return (0);
else if (ISSET(iflag, BRKINT)) {
ttyflush(tp, FREAD | FWRITE);
ttysig(tp, TTYSIG_PG1, SIGINT);
return (0);
} else if (ISSET(iflag, PARMRK))
goto parmrk;
} else if ((ISSET(error, TTY_PE) && ISSET(iflag, INPCK)) ||
ISSET(error, TTY_FE)) {
if (ISSET(iflag, IGNPAR))
return (0);
else if (ISSET(iflag, PARMRK)) {
parmrk: (void)putc(0377 | TTY_QUOTE, &tp->t_rawq);
(void)putc(0 | TTY_QUOTE, &tp->t_rawq);
(void)putc(c | TTY_QUOTE, &tp->t_rawq);
return (0);
} else
c = 0;
}
} else if (c == 0377 &&
ISSET(iflag, ISTRIP|IGNPAR|INPCK|PARMRK) == (INPCK|PARMRK)) {
/* "Escape" a valid character of '\377'. */
(void)putc(0377 | TTY_QUOTE, &tp->t_rawq);
(void)putc(0377 | TTY_QUOTE, &tp->t_rawq);
goto endcase;
}
/*
* In tandem mode, check high water mark.
*/
if (ISSET(iflag, IXOFF) || ISSET(tp->t_cflag, CHWFLOW))
ttyblock(tp);
if (!ISSET(tp->t_state, TS_TYPEN) && ISSET(iflag, ISTRIP))
CLR(c, 0x80);
if (!ISSET(lflag, EXTPROC)) {
/*
* Check for literal nexting very first
*/
if (ISSET(tp->t_state, TS_LNCH)) {
SET(c, TTY_QUOTE);
CLR(tp->t_state, TS_LNCH);
}
/*
* Scan for special characters. This code
* is really just a big case statement with
* non-constant cases. The bottom of the
* case statement is labeled ``endcase'', so goto
* it after a case match, or similar.
*/
/*
* Control chars which aren't controlled
* by ICANON, ISIG, or IXON.
*/
if (ISSET(lflag, IEXTEN)) {
if (CCEQ(cc[VLNEXT], c)) {
if (ISSET(lflag, ECHO)) {
if (ISSET(lflag, ECHOE)) {
(void)ttyoutput('^', tp);
(void)ttyoutput('\b', tp);
} else
ttyecho(c, tp);
}
SET(tp->t_state, TS_LNCH);
goto endcase;
}
if (CCEQ(cc[VDISCARD], c)) {
if (ISSET(lflag, FLUSHO))
CLR(tp->t_lflag, FLUSHO);
else {
ttyflush(tp, FWRITE);
ttyecho(c, tp);
if (tp->t_rawq.c_cc + tp->t_canq.c_cc)
ttyretype(tp);
SET(tp->t_lflag, FLUSHO);
}
goto startoutput;
}
}
/*
* Signals.
*/
if (ISSET(lflag, ISIG)) {
if (CCEQ(cc[VINTR], c) || CCEQ(cc[VQUIT], c)) {
if (!ISSET(lflag, NOFLSH))
ttyflush(tp, FREAD | FWRITE);
ttyecho(c, tp);
ttysig(tp, TTYSIG_PG1, CCEQ(cc[VINTR], c) ?
SIGINT : SIGQUIT);
goto endcase;
}
if (CCEQ(cc[VSUSP], c)) {
if (!ISSET(lflag, NOFLSH))
ttyflush(tp, FREAD);
ttyecho(c, tp);
ttysig(tp, TTYSIG_PG1, SIGTSTP);
goto endcase;
}
}
/*
* Handle start/stop characters.
*/
if (ISSET(iflag, IXON)) {
if (CCEQ(cc[VSTOP], c)) {
if (!ISSET(tp->t_state, TS_TTSTOP)) {
SET(tp->t_state, TS_TTSTOP);
cdev_stop(tp, 0);
return (0);
}
if (!CCEQ(cc[VSTART], c))
return (0);
/*
* if VSTART == VSTOP then toggle
*/
goto endcase;
}
if (CCEQ(cc[VSTART], c))
goto restartoutput;
}
/*
* IGNCR, ICRNL, & INLCR
*/
if (c == '\r') {
if (ISSET(iflag, IGNCR))
goto endcase;
else if (ISSET(iflag, ICRNL))
c = '\n';
} else if (c == '\n' && ISSET(iflag, INLCR))
c = '\r';
}
if (!ISSET(lflag, EXTPROC) && ISSET(lflag, ICANON)) {
/*
* From here on down canonical mode character
* processing takes place.
*/
/*
* erase (^H / ^?)
*/
if (CCEQ(cc[VERASE], c)) {
if (tp->t_rawq.c_cc)
ttyrub(unputc(&tp->t_rawq), tp);
goto endcase;
}
/*
* kill (^U)
*/
if (CCEQ(cc[VKILL], c)) {
if (ISSET(lflag, ECHOKE) &&
tp->t_rawq.c_cc == tp->t_rocount &&
!ISSET(lflag, ECHOPRT))
while (tp->t_rawq.c_cc)
ttyrub(unputc(&tp->t_rawq), tp);
else {
ttyecho(c, tp);
if (ISSET(lflag, ECHOK) ||
ISSET(lflag, ECHOKE))
ttyecho('\n', tp);
FLUSHQ(&tp->t_rawq);
tp->t_rocount = 0;
}
CLR(tp->t_state, TS_LOCAL);
goto endcase;
}
/*
* Extensions to the POSIX.1 GTI set of functions.
*/
if (ISSET(lflag, IEXTEN)) {
/*
* word erase (^W)
*/
if (CCEQ(cc[VWERASE], c)) {
int alt = ISSET(lflag, ALTWERASE);
int ctype;
/*
* erase whitespace
*/
while ((c = unputc(&tp->t_rawq)) == ' ' ||
c == '\t')
ttyrub(c, tp);
if (c == -1)
goto endcase;
/*
* erase last char of word and remember the
* next chars type (for ALTWERASE)
*/
ttyrub(c, tp);
c = unputc(&tp->t_rawq);
if (c == -1)
goto endcase;
if (c == ' ' || c == '\t') {
(void)putc(c, &tp->t_rawq);
goto endcase;
}
ctype = ISALPHA(c);
/*
* erase rest of word
*/
do {
ttyrub(c, tp);
c = unputc(&tp->t_rawq);
if (c == -1)
goto endcase;
} while (c != ' ' && c != '\t' &&
(alt == 0 || ISALPHA(c) == ctype));
(void)putc(c, &tp->t_rawq);
goto endcase;
}
/*
* reprint line (^R)
*/
if (CCEQ(cc[VREPRINT], c)) {
ttyretype(tp);
goto endcase;
}
/*
* ^T - kernel info and generate SIGINFO
*/
if (CCEQ(cc[VSTATUS], c)) {
ttysig(tp, TTYSIG_PG1, SIGINFO);
goto endcase;
}
}
}
/*
* Check for input buffer overflow
*/
if (tp->t_rawq.c_cc + tp->t_canq.c_cc >= TTYHOG) {
if (ISSET(iflag, IMAXBEL)) {
if (tp->t_outq.c_cc < tp->t_hiwat)
(void)ttyoutput(CTRL('g'), tp);
} else
ttyflush(tp, FREAD | FWRITE);
goto endcase;
}
/*
* Put data char in q for user and
* wakeup on seeing a line delimiter.
*/
if (putc(c, &tp->t_rawq) >= 0) {
if (!ISSET(lflag, ICANON)) {
ttwakeup(tp);
ttyecho(c, tp);
goto endcase;
}
if (TTBREAKC(c, lflag)) {
tp->t_rocount = 0;
catq(&tp->t_rawq, &tp->t_canq);
ttwakeup(tp);
} else if (tp->t_rocount++ == 0)
tp->t_rocol = tp->t_column;
if (ISSET(tp->t_state, TS_ERASE)) {
/*
* end of prterase \.../
*/
CLR(tp->t_state, TS_ERASE);
(void)ttyoutput('/', tp);
}
i = tp->t_column;
ttyecho(c, tp);
if (CCEQ(cc[VEOF], c) && ISSET(lflag, ECHO)) {
/*
* Place the cursor over the '^' of the ^D.
*/
i = uimin(2, tp->t_column - i);
while (i > 0) {
(void)ttyoutput('\b', tp);
i--;
}
}
}
endcase:
/*
* IXANY means allow any character to restart output.
*/
if (ISSET(tp->t_state, TS_TTSTOP) &&
!ISSET(iflag, IXANY) && cc[VSTART] != cc[VSTOP]) {
return (0);
}
restartoutput:
CLR(tp->t_lflag, FLUSHO);
CLR(tp->t_state, TS_TTSTOP);
startoutput:
return (ttstart(tp));
}
/*
* Process input of a single character received on a tty.
*
* XXX - this is a hack, all drivers must changed to acquire the
* lock before calling linesw->l_rint()
*/
int
ttyinput(int c, struct tty *tp)
{
int error;
/*
* Unless the receiver is enabled, drop incoming data.
*/
if (!ISSET(tp->t_cflag, CREAD))
return (0);
/*
* Output a single character on a tty, doing output processing
* as needed (expanding tabs, newline processing, etc.).
* Returns < 0 if succeeds, otherwise returns char to resend.
* Must be recursive.
*
* Call with tty lock held.
*/
int
ttyoutput(int c, struct tty *tp)
{
long oflag;
int col, notout;
KASSERT(mutex_owned(&tty_lock));
oflag = tp->t_oflag;
if (!ISSET(oflag, OPOST)) {
tk_nout++;
tp->t_outcc++;
if (!ISSET(tp->t_lflag, FLUSHO) && putc(c, &tp->t_outq))
return (c);
return (-1);
}
/*
* Do tab expansion if OXTABS is set. Special case if we do external
* processing, we don't do the tab expansion because we'll probably
* get it wrong. If tab expansion needs to be done, let it happen
* externally.
*/
CLR(c, ~TTY_CHARMASK);
if (c == '\t' &&
ISSET(oflag, OXTABS) && !ISSET(tp->t_lflag, EXTPROC)) {
c = 8 - (tp->t_column & 7);
if (ISSET(tp->t_lflag, FLUSHO)) {
notout = 0;
} else {
notout = b_to_q(" ", c, &tp->t_outq);
c -= notout;
tk_nout += c;
tp->t_outcc += c;
}
tp->t_column += c;
return (notout ? '\t' : -1);
}
if (c == CEOT && ISSET(oflag, ONOEOT))
return (-1);
/*
* Newline translation: if ONLCR is set,
* translate newline into "\r\n".
*/
if (c == '\n' && ISSET(tp->t_oflag, ONLCR)) {
tk_nout++;
tp->t_outcc++;
if (!ISSET(tp->t_lflag, FLUSHO) && putc('\r', &tp->t_outq))
return (c);
}
/* If OCRNL is set, translate "\r" into "\n". */
else if (c == '\r' && ISSET(tp->t_oflag, OCRNL))
c = '\n';
/* If ONOCR is set, don't transmit CRs when on column 0. */
else if (c == '\r' && ISSET(tp->t_oflag, ONOCR) && tp->t_column == 0)
return (-1);
tk_nout++;
tp->t_outcc++;
if (!ISSET(tp->t_lflag, FLUSHO) && putc(c, &tp->t_outq))
return (c);
col = tp->t_column;
switch (CCLASS(c)) {
case BACKSPACE:
if (col > 0)
--col;
break;
case CONTROL:
break;
case NEWLINE:
if (ISSET(tp->t_oflag, ONLCR | ONLRET))
col = 0;
break;
case RETURN:
col = 0;
break;
case ORDINARY:
++col;
break;
case TAB:
col = (col + 8) & ~7;
break;
}
tp->t_column = col;
return (-1);
}
/*
* Ioctls for all tty devices. Called after line-discipline specific ioctl
* has been called to do discipline-specific functions and/or reject any
* of these ioctl commands.
*/
/* ARGSUSED */
int
ttioctl(struct tty *tp, u_long cmd, void *data, int flag, struct lwp *l)
{
struct proc *p;
struct linesw *lp;
int s, error;
struct pathbuf *pb;
struct nameidata nd;
char infobuf[200];
KASSERT(l != NULL);
p = l->l_proc;
/* If the ioctl involves modification, hang if in the background. */
switch (cmd) {
case TIOCFLUSH:
case TIOCDRAIN:
case TIOCSBRK:
case TIOCCBRK:
case TIOCSTART:
case TIOCSETA:
case TIOCSETD:
case TIOCSLINED:
case TIOCSETAF:
case TIOCSETAW:
#ifdef notdef
case TIOCSPGRP:
case FIOSETOWN:
#endif
case TIOCSTAT:
case TIOCSTI:
case TIOCSWINSZ:
case TIOCSQSIZE:
case TIOCLBIC:
case TIOCLBIS:
case TIOCLSET:
case TIOCSETC:
case OTIOCSETD:
case TIOCSETN:
case TIOCSETP:
case TIOCSLTC:
mutex_spin_enter(&tty_lock);
while (isbackground(curproc, tp) &&
p->p_pgrp->pg_jobc && (p->p_lflag & PL_PPWAIT) == 0 &&
!sigismasked(l, SIGTTOU)) {
mutex_spin_exit(&tty_lock);
if (lp != tp->t_linesw) {
device = tp->t_dev;
s = spltty();
(*tp->t_linesw->l_close)(tp, flag);
error = (*lp->l_open)(device, tp);
if (error) {
(void)(*tp->t_linesw->l_open)(device, tp);
splx(s);
ttyldisc_release(lp);
return (error);
}
ttyldisc_release(tp->t_linesw);
tp->t_linesw = lp;
splx(s);
} else {
/* Drop extra reference. */
ttyldisc_release(lp);
}
break;
}
case TIOCSTART: /* start output, like ^Q */
mutex_spin_enter(&tty_lock);
if (ISSET(tp->t_state, TS_TTSTOP) ||
ISSET(tp->t_lflag, FLUSHO)) {
CLR(tp->t_lflag, FLUSHO);
CLR(tp->t_state, TS_TTSTOP);
ttstart(tp);
}
mutex_spin_exit(&tty_lock);
break;
case TIOCSTI: /* simulate terminal input */
if ((error = kauth_authorize_device_tty(l->l_cred,
KAUTH_DEVICE_TTY_STI, tp)) != 0) {
if (!ISSET(flag, FREAD))
return EPERM;
if (!isctty(p, tp))
return EACCES;
if (tp->t_session->s_leader->p_cred != p->p_cred)
return error;
}
(*tp->t_linesw->l_rint)(*(u_char *)data, tp);
break;
case TIOCSTOP: /* stop output, like ^S */
{
mutex_spin_enter(&tty_lock);
if (!ISSET(tp->t_state, TS_TTSTOP)) {
SET(tp->t_state, TS_TTSTOP);
cdev_stop(tp, 0);
}
mutex_spin_exit(&tty_lock);
break;
}
case TIOCSCTTY: /* become controlling tty */
mutex_enter(&proc_lock);
mutex_spin_enter(&tty_lock);
/* Session ctty vnode pointer set in vnode layer. */
if (!SESS_LEADER(p) ||
((p->p_session->s_ttyvp || tp->t_session) &&
(tp->t_session != p->p_session))) {
mutex_spin_exit(&tty_lock);
mutex_exit(&proc_lock);
return (EPERM);
}
/*
* `p_session' acquires a reference.
* But note that if `t_session' is set at this point,
* it must equal `p_session', in which case the session
* already has the correct reference count.
*/
if (tp->t_session == NULL) {
proc_sesshold(p->p_session);
}
tp->t_session = p->p_session;
tp->t_pgrp = p->p_pgrp;
p->p_session->s_ttyp = tp;
p->p_lflag |= PL_CONTROLT;
mutex_spin_exit(&tty_lock);
mutex_exit(&proc_lock);
break;
case FIOSETOWN: { /* set pgrp of tty */
pid_t pgid = *(pid_t *)data;
struct pgrp *pgrp;
mutex_spin_enter(&tty_lock);
ttyputinfo(tp, infobuf);
mutex_spin_exit(&tty_lock);
break;
case TIOCSWINSZ: /* set window size */
mutex_spin_enter(&tty_lock);
if (memcmp((void *)&tp->t_winsize, data,
sizeof(struct winsize))) {
tp->t_winsize = *(struct winsize *)data;
ttysig(tp, TTYSIG_PG1, SIGWINCH);
}
mutex_spin_exit(&tty_lock);
break;
case TIOCSQSIZE:
if ((error = tty_get_qsize(&s, *(int *)data)) == 0 &&
s != tp->t_qsize)
error = tty_set_qsize(tp, s);
return error;
case TIOCSBRK:
case TIOCCBRK:
case TIOCSDTR:
case TIOCCDTR:
case TIOCSFLAGS:
case TIOCGFLAGS:
case TIOCMSET:
case TIOCMGET:
case TIOCMBIS:
case TIOCMBIC:
/* Handled by the driver layer */
return EPASSTHROUGH;
case TIOCEXT:
case TIOCPTSNAME:
case TIOCGRANTPT:
case TIOCPKT:
case TIOCUCNTL:
case TIOCREMOTE:
case TIOCSIG:
/* for ptys */
return EPASSTHROUGH;
default:
/* Pass through various console ioctls */
switch (IOCGROUP(cmd)) {
case 'c': /* syscons console */
case 'v': /* usl console, video - where one letter */
case 'K': /* usl console, keyboard - aint enough */
case 'V': /* pcvt compat */
case 'W': /* wscons console */
return EPASSTHROUGH;
default:
break;
}
/* We may have to load the compat_60 module for this. */
(void)module_autoload("compat_60", MODULE_CLASS_EXEC);
MODULE_HOOK_CALL(tty_ttioctl_60_hook,
(tp, cmd, data, flag, l), enosys(), error);
if (error != EPASSTHROUGH)
return error;
/* We may have to load the compat_43 module for this. */
(void)module_autoload("compat_43", MODULE_CLASS_EXEC);
MODULE_HOOK_CALL(tty_ttioctl_43_hook,
(tp, cmd, data, flag, l), enosys(), error);
return error;
}
return (0);
}
int
ttpoll(struct tty *tp, int events, struct lwp *l)
{
int revents;
/*
* Handle modem control transition on a tty.
* Flag indicates new state of carrier.
* Returns 0 if the line should be turned off, otherwise 1.
*/
int
ttymodem(struct tty *tp, int flag)
{
mutex_spin_enter(&tty_lock);
if (flag == 0) {
if (ISSET(tp->t_state, TS_CARR_ON)) {
/*
* Lost carrier.
*/
CLR(tp->t_state, TS_CARR_ON);
if (ISSET(tp->t_state, TS_ISOPEN) && !CONNECTED(tp)) {
ttysig(tp, TTYSIG_LEADER, SIGHUP);
ttyflush(tp, FREAD | FWRITE);
mutex_spin_exit(&tty_lock);
return (0);
}
}
} else {
if (!ISSET(tp->t_state, TS_CARR_ON)) {
/*
* Carrier now on.
*/
SET(tp->t_state, TS_CARR_ON);
ttwakeup(tp);
}
}
mutex_spin_exit(&tty_lock);
return (1);
}
/*
* Default modem control routine (for other line disciplines).
* Return argument flag, to turn off device on carrier drop.
*/
int
nullmodem(struct tty *tp, int flag)
{
cc = tp->t_cc;
p = curproc;
error = 0;
has_stime = 0;
last_cc = 0;
slp = 0;
loop:
mutex_spin_enter(&tty_lock);
lflag = tp->t_lflag;
/*
* take pending input first
*/
if (ISSET(lflag, PENDIN))
ttypend(tp);
/*
* Hang process if it's in the background.
*/
if (isbackground(p, tp)) {
if (sigismasked(curlwp, SIGTTIN) ||
p->p_lflag & PL_PPWAIT || p->p_pgrp->pg_jobc == 0) {
mutex_spin_exit(&tty_lock);
return (EIO);
}
mutex_spin_exit(&tty_lock);
if (!ISSET(lflag, ICANON)) {
int m = cc[VMIN];
long t = cc[VTIME];
qp = &tp->t_rawq;
/*
* Check each of the four combinations.
* (m > 0 && t == 0) is the normal read case.
* It should be fairly efficient, so we check that and its
* companion case (m == 0 && t == 0) first.
* For the other two cases, we compute the target sleep time
* into slp.
*/
if (t == 0) {
if (qp->c_cc < m)
goto sleep;
goto read;
}
t *= hz; /* time in deca-ticks */
/*
* Time difference in deca-ticks, split division to avoid numeric overflow.
* Ok for hz < ~200kHz
*/
#define diff(t1, t2) (((t1).tv_sec - (t2).tv_sec) * 10 * hz + \
((t1).tv_usec - (t2).tv_usec) / 100 * hz / 1000)
if (m > 0) {
if (qp->c_cc <= 0)
goto sleep;
if (qp->c_cc >= m)
goto read;
if (!has_stime) {
/* first character, start timer */
has_stime = 1;
getmicrotime(&stime);
slp = t;
} else if (qp->c_cc > last_cc) {
/* got a character, restart timer */
getmicrotime(&stime);
slp = t;
} else {
/* nothing, check expiration */
getmicrotime(&now);
slp = t - diff(now, stime);
}
} else { /* m == 0 */
if (qp->c_cc > 0)
goto read;
if (!has_stime) {
has_stime = 1;
getmicrotime(&stime);
slp = t;
} else {
getmicrotime(&now);
slp = t - diff(now, stime);
}
}
last_cc = qp->c_cc;
#undef diff
if (slp > 0) {
/*
* Convert deca-ticks back to ticks.
* Rounding down may make us wake up just short
* of the target, so we round up.
* Maybe we should do 'slp/10 + 1' because the
* first tick maybe almost immediate.
* However it is more useful for a program that sets
* VTIME=10 to wakeup every second not every 1.01
* seconds (if hz=100).
*/
slp = (slp + 9)/ 10;
goto sleep;
}
} else if ((qp = &tp->t_canq)->c_cc <= 0) {
int carrier;
sleep:
/*
* If there is no input, sleep on rawq
* awaiting hardware receipt and notification.
* If we have data, we don't need to check for carrier.
*/
carrier = CONNECTED(tp);
if (!carrier && ISSET(tp->t_state, TS_ISOPEN)) {
mutex_spin_exit(&tty_lock);
return (0); /* EOF */
}
if (!has_stime || slp <= 0) {
if (flag & IO_NDELAY) {
mutex_spin_exit(&tty_lock);
return (EWOULDBLOCK);
}
}
error = ttysleep(tp, &tp->t_rawcv, true, slp);
mutex_spin_exit(&tty_lock);
/* VMIN == 0: any quantity read satisfies */
if (cc[VMIN] == 0 && error == EWOULDBLOCK)
return (0);
if (error && error != EWOULDBLOCK)
return (error);
goto loop;
}
read:
/*
* Input present, check for input mapping and processing.
*/
first = 1;
while ((c = getc(qp)) >= 0) {
/*
* delayed suspend (^Y)
*/
if (CCEQ(cc[VDSUSP], c) &&
ISSET(lflag, IEXTEN|ISIG) == (IEXTEN|ISIG)) {
ttysig(tp, TTYSIG_PG1, SIGTSTP);
if (first) {
error = ttypause(tp, hz);
if (error)
break;
mutex_spin_exit(&tty_lock);
goto loop;
}
break;
}
/*
* Interpret EOF only in canonical mode.
*/
if (CCEQ(cc[VEOF], c) && ISSET(lflag, ICANON))
break;
/*
* Give user character.
*/
mutex_spin_exit(&tty_lock);
error = ureadc(c, uio);
mutex_spin_enter(&tty_lock);
if (error)
break;
if (uio->uio_resid == 0)
break;
/*
* In canonical mode check for a "break character"
* marking the end of a "line of input".
*/
if (ISSET(lflag, ICANON) && TTBREAKC(c, lflag))
break;
first = 0;
}
/*
* Look to unblock output now that (presumably)
* the input queue has gone down.
*/
if (ISSET(tp->t_state, TS_TBLOCK) && tp->t_rawq.c_cc < TTYHOG / 5) {
if (ISSET(tp->t_iflag, IXOFF) &&
cc[VSTART] != _POSIX_VDISABLE &&
putc(cc[VSTART], &tp->t_outq) == 0) {
CLR(tp->t_state, TS_TBLOCK);
ttstart(tp);
}
/* Try to unblock remote output via hardware flow control. */
if (ISSET(tp->t_cflag, CHWFLOW) && tp->t_hwiflow &&
(*tp->t_hwiflow)(tp, 0) != 0)
CLR(tp->t_state, TS_TBLOCK);
}
mutex_spin_exit(&tty_lock);
return (error);
}
/*
* Check the output queue on tp for space for a kernel message (from uprintf
* or tprintf). Allow some space over the normal hiwater mark so we don't
* lose messages due to normal flow control, but don't let the tty run amok.
* Sleeps here are not interruptible, but we return prematurely if new signals
* arrive.
* Call with tty lock held.
*/
static int
ttycheckoutq_wlock(struct tty *tp)
{
int hiwat;
KASSERT(mutex_owned(&tty_lock));
hiwat = tp->t_hiwat;
if (tp->t_outq.c_cc > hiwat + 200)
if (tp->t_outq.c_cc > hiwat) {
ttstart(tp);
return (0);
}
return (1);
}
int
ttycheckoutq(struct tty *tp)
{
int r;
mutex_spin_enter(&tty_lock);
r = ttycheckoutq_wlock(tp);
mutex_spin_exit(&tty_lock);
return (r);
}
/*
* Process a write call on a tty device.
*/
int
ttwrite(struct tty *tp, struct uio *uio, int flag)
{
u_char *cp;
struct proc *p;
int cc, cc0, ce, i, hiwat, error;
u_char obuf[OBUFSIZ];
/*
* Hang the process if it's in the background.
*/
p = curproc;
if (isbackground(p, tp) &&
ISSET(tp->t_lflag, TOSTOP) && (p->p_lflag & PL_PPWAIT) == 0 &&
!sigismasked(curlwp, SIGTTOU)) {
if (p->p_pgrp->pg_jobc == 0) {
error = EIO;
mutex_spin_exit(&tty_lock);
goto out;
}
mutex_spin_exit(&tty_lock);
/*
* Process the user's data in at most OBUFSIZ chunks. Perform any
* output translation. Keep track of high water mark, sleep on
* overflow awaiting device aid in acquiring new space.
*/
while (uio->uio_resid > 0 || cc > 0) {
if (ISSET(tp->t_lflag, FLUSHO)) {
uio->uio_resid = 0;
return (0);
}
if (tp->t_outq.c_cc > hiwat)
goto ovhiwat;
/*
* Grab a hunk of data from the user, unless we have some
* leftover from last time.
*/
if (cc == 0) {
uioskip(cc0, uio);
cc0 = cc = uimin(uio->uio_resid, OBUFSIZ);
cp = obuf;
error = uiopeek(cp, cc, uio);
if (error) {
cc = 0;
goto out;
}
}
/*
* If nothing fancy need be done, grab those characters we
* can handle without any of ttyoutput's processing and
* just transfer them to the output q. For those chars
* which require special processing (as indicated by the
* bits in char_type), call ttyoutput. After processing
* a hunk of data, look for FLUSHO so ^O's will take effect
* immediately.
*/
mutex_spin_enter(&tty_lock);
while (cc > 0) {
if (!ISSET(tp->t_oflag, OPOST))
ce = cc;
else {
ce = cc - scanc((u_int)cc, cp, char_type,
CCLASSMASK);
/*
* If ce is zero, then we're processing
* a special character through ttyoutput.
*/
if (ce == 0) {
tp->t_rocount = 0;
if (ttyoutput(*cp, tp) >= 0) {
/* out of space */
mutex_spin_exit(&tty_lock);
goto overfull;
}
cp++;
cc--;
if (ISSET(tp->t_lflag, FLUSHO) ||
tp->t_outq.c_cc > hiwat) {
mutex_spin_exit(&tty_lock);
goto ovhiwat;
}
continue;
}
}
/*
* A bunch of normal characters have been found.
* Transfer them en masse to the output queue and
* continue processing at the top of the loop.
* If there are any further characters in this
* <= OBUFSIZ chunk, the first should be a character
* requiring special handling by ttyoutput.
*/
tp->t_rocount = 0;
i = b_to_q(cp, ce, &tp->t_outq);
ce -= i;
tp->t_column += ce;
cp += ce, cc -= ce, tk_nout += ce;
tp->t_outcc += ce;
if (i > 0) {
/* out of space */
mutex_spin_exit(&tty_lock);
goto overfull;
}
if (ISSET(tp->t_lflag, FLUSHO) ||
tp->t_outq.c_cc > hiwat)
break;
}
ttstart(tp);
mutex_spin_exit(&tty_lock);
}
overfull:
/*
* Since we are using ring buffers, if we can't insert any more into
* the output queue, we can assume the ring is full and that someone
* forgot to set the high water mark correctly. We set it and then
* proceed as normal.
*/
hiwat = tp->t_outq.c_cc - 1;
ovhiwat:
mutex_spin_enter(&tty_lock);
ttstart(tp);
/*
* This can only occur if FLUSHO is set in t_lflag,
* or if ttstart/oproc is synchronous (or very fast).
*/
if (tp->t_outq.c_cc <= hiwat) {
mutex_spin_exit(&tty_lock);
goto loop;
}
if (flag & IO_NDELAY) {
mutex_spin_exit(&tty_lock);
error = EWOULDBLOCK;
goto out;
}
error = ttysleep(tp, &tp->t_outcv, true, 0);
mutex_spin_exit(&tty_lock);
if (error)
goto out;
goto loop;
}
/*
* Try to pull more output from the producer. Return non-zero if
* there is output ready to be sent.
*/
bool
ttypull(struct tty *tp)
{
/* XXXSMP not yet KASSERT(mutex_owned(&tty_lock)); */
/*
* Rubout one character from the rawq of tp
* as cleanly as possible.
* Called with tty lock held.
*/
void
ttyrub(int c, struct tty *tp)
{
u_char *cp;
int savecol, tabc;
KASSERT(mutex_owned(&tty_lock));
if (!ISSET(tp->t_lflag, ECHO) || ISSET(tp->t_lflag, EXTPROC))
return;
CLR(tp->t_lflag, FLUSHO);
if (ISSET(tp->t_lflag, ECHOE)) {
if (tp->t_rocount == 0) {
/*
* Screwed by ttwrite; retype
*/
ttyretype(tp);
return;
}
if (c == ('\t' | TTY_QUOTE) || c == ('\n' | TTY_QUOTE))
ttyrubo(tp, 2);
else {
CLR(c, ~TTY_CHARMASK);
switch (CCLASS(c)) {
case ORDINARY:
ttyrubo(tp, 1);
break;
case BACKSPACE:
case CONTROL:
case NEWLINE:
case RETURN:
case VTAB:
if (ISSET(tp->t_lflag, ECHOCTL))
ttyrubo(tp, 2);
break;
case TAB:
if (tp->t_rocount < tp->t_rawq.c_cc) {
ttyretype(tp);
return;
}
savecol = tp->t_column;
SET(tp->t_state, TS_CNTTB);
SET(tp->t_lflag, FLUSHO);
tp->t_column = tp->t_rocol;
for (cp = firstc(&tp->t_rawq, &tabc); cp;
cp = nextc(&tp->t_rawq, cp, &tabc))
ttyecho(tabc, tp);
CLR(tp->t_lflag, FLUSHO);
CLR(tp->t_state, TS_CNTTB);
/* savecol will now be length of the tab. */
savecol -= tp->t_column;
tp->t_column += savecol;
if (savecol > 8)
savecol = 8; /* overflow screw */
while (--savecol >= 0)
(void)ttyoutput('\b', tp);
break;
default: /* XXX */
(void)printf("ttyrub: would panic c = %d, "
"val = %d\n", c, CCLASS(c));
}
}
} else if (ISSET(tp->t_lflag, ECHOPRT)) {
if (!ISSET(tp->t_state, TS_ERASE)) {
SET(tp->t_state, TS_ERASE);
(void)ttyoutput('\\', tp);
}
ttyecho(c, tp);
} else
ttyecho(tp->t_cc[VERASE], tp);
--tp->t_rocount;
}
/*
* Back over cnt characters, erasing them.
* Called with tty lock held.
*/
static void
ttyrubo(struct tty *tp, int cnt)
{
/*
* ttyretype --
* Reprint the rawq line. Note, it is assumed that c_cc has already
* been checked.
*
* Called with tty lock held.
*/
void
ttyretype(struct tty *tp)
{
u_char *cp;
int c;
KASSERT(mutex_owned(&tty_lock));
/* Echo the reprint character. */
if (tp->t_cc[VREPRINT] != _POSIX_VDISABLE)
ttyecho(tp->t_cc[VREPRINT], tp);
/*
* Look up a code for a specified speed in a conversion table;
* used by drivers to map software speed values to hardware parameters.
*/
int
ttspeedtab(int speed, const struct speedtab *table)
{
for (; table->sp_speed != -1; table++)
if (table->sp_speed == speed)
return (table->sp_code);
return (-1);
}
/*
* Set tty hi and low water marks.
*
* Try to arrange the dynamics so there's about one second
* from hi to low water.
*/
void
ttsetwater(struct tty *tp)
{
int cps, x;
/* XXX not yet KASSERT(mutex_owned(&tty_lock)); */
#define CLAMP(x, h, l) ((x) > h ? h : ((x) < l) ? l : (x))
cps = tp->t_ospeed / 10;
tp->t_lowat = x = CLAMP(cps / 2, TTMAXLOWAT, TTMINLOWAT);
x += cps;
x = CLAMP(x, TTMAXHIWAT, TTMINHIWAT);
tp->t_hiwat = roundup(x, TTROUND);
#undef CLAMP
}
/*
* Prepare report on state of foreground process group.
* Call with &proc_lock held.
*/
void
ttygetinfo(struct tty *tp, int fromsig, char *buf, size_t bufsz)
{
struct lwp *l;
struct proc *p, *pick = NULL;
struct timeval utime, stime;
int tmp;
fixpt_t pctcpu = 0;
const char *msg = NULL;
char lmsg[100];
long rss;
bool again = false;
KASSERT(mutex_owned(&proc_lock));
*buf = '\0';
retry:
if (tp->t_session == NULL)
msg = "not a controlling terminal\n";
else if (tp->t_pgrp == NULL)
msg = "no foreground process group\n";
else if ((p = LIST_FIRST(&tp->t_pgrp->pg_members)) == NULL)
msg = "empty foreground process group\n";
else {
/* Pick interesting process. */
for (; p != NULL; p = LIST_NEXT(p, p_pglist)) {
struct proc *oldpick;
if (pick == NULL) {
pick = p;
continue;
}
if (pick->p_lock < p->p_lock) {
mutex_enter(pick->p_lock);
mutex_enter(p->p_lock);
} else if (pick->p_lock > p->p_lock) {
mutex_enter(p->p_lock);
mutex_enter(pick->p_lock);
} else
mutex_enter(p->p_lock);
oldpick = pick;
if (proc_compare_wrapper(pick, p))
pick = p;
mutex_exit(p->p_lock);
if (p->p_lock != oldpick->p_lock)
mutex_exit(oldpick->p_lock);
}
if (pick != NULL) {
mutex_enter(pick->p_lock);
if (P_ZOMBIE(pick)) {
mutex_exit(pick->p_lock);
pick = NULL;
if (!again) {
again = true;
goto retry;
}
msg = "found only zombie processes\n";
}
if (pick && fromsig &&
(SIGACTION_PS(pick->p_sigacts, SIGINFO).sa_flags &
SA_NOKERNINFO)) {
mutex_exit(pick->p_lock);
return;
}
}
}
/*
* Print report on state of foreground process group.
* Call with tty_lock held.
*/
void
ttyputinfo(struct tty *tp, char *buf)
{
KASSERT(mutex_owned(&tty_lock));
if (ttycheckoutq_wlock(tp) == 0)
return;
ttyprintf_nolock(tp, "%s\n", buf);
tp->t_rocount = 0; /* so pending input will be retyped if BS */
}
/*
* Returns 1 if p2 has a better chance being the active foreground process
* in a terminal instead of p1.
*/
static int
proc_compare_wrapper(struct proc *p1, struct proc *p2)
{
lwp_t *l1, *l2;
/*
* Output char to tty; console putchar style.
* Can be called with tty lock held through kprintf() machinery..
*/
int
tputchar(int c, int flags, struct tty *tp)
{
int r = 0;
if ((flags & NOLOCK) == 0)
mutex_spin_enter(&tty_lock);
if (!CONNECTED(tp)) {
r = -1;
goto out;
}
if (c == '\n')
(void)ttyoutput('\r', tp);
(void)ttyoutput(c, tp);
ttstart(tp);
out:
if ((flags & NOLOCK) == 0)
mutex_spin_exit(&tty_lock);
return (r);
}
/*
* Sleep on chan, returning ERESTART if tty changed while we napped and
* returning any errors (e.g. EINTR/EWOULDBLOCK) reported by
* cv_timedwait(_sig).
* If the tty is revoked, restarting a pending call will redo validation done
* at the start of the call.
*
* Must be called with the tty lock held.
*/
int
ttysleep(struct tty *tp, kcondvar_t *cv, bool catch_p, int timo)
{
int error;
short gen;
KASSERT(mutex_owned(&tty_lock));
gen = tp->t_gen;
if (ISSET(tp->t_state, TS_CANCEL))
error = ERESTART;
else if (cv == NULL)
error = kpause("ttypause", catch_p, timo, &tty_lock);
else if (catch_p)
error = cv_timedwait_sig(cv, &tty_lock, timo);
else
error = cv_timedwait(cv, &tty_lock, timo);
if (error != 0)
return (error);
return (tp->t_gen == gen ? 0 : ERESTART);
}
int
ttypause(struct tty *tp, int timo)
{
int error;
/*
* Attach a tty to the tty list.
*
* This should be called ONLY once per real tty (including pty's).
* eg, on the sparc, the keyboard and mouse have struct tty's that are
* distinctly NOT usable as tty's, and thus should not be attached to
* the ttylist. This is why this call is not done from tty_alloc().
*
* Device drivers should attach tty's at a similar time that they are
* allocated, or, for the case of statically allocated struct tty's
* either in the attach or (first) open routine.
*/
void
tty_attach(struct tty *tp)
{
/*
* Free a tty structure and its buffers.
*
* Be sure to call tty_detach() for any tty that has been
* tty_attach()ed.
*/
void
tty_free(struct tty *tp)
{
int i;
mutex_enter(&proc_lock);
mutex_enter(&tty_lock);
for (i = 0; i < TTYSIG_COUNT; i++)
sigemptyset(&tp->t_sigs[i]);
if (tp->t_sigcount != 0)
TAILQ_REMOVE(&tty_sigqueue, tp, t_sigqueue);
mutex_exit(&tty_lock);
mutex_exit(&proc_lock);
/*
* tty_unit: map dev_t to tty unit number, as with TTUNIT
*
* => defined as function for use with struct cdevsw::d_devtounit
* => not for drivers with different unit numbering, e.g. TTUNIT(d) >> 4
*/
int
tty_unit(dev_t dev)
{
return TTUNIT(dev);
}
/*
* ttyprintf_nolock: send a message to a specific tty, without locking.
*
* => should be used only by tty driver or anything that knows the
* underlying tty will not be revoked(2)'d away. [otherwise,
* use tprintf]
*/
static void
ttyprintf_nolock(struct tty *tp, const char *fmt, ...)
{
va_list ap;
/* No mutex needed; going to process TTY. */
va_start(ap, fmt);
kprintf(fmt, TOTTY|NOLOCK, tp, NULL, ap);
va_end(ap);
}
if (action != KAUTH_DEVICE_TTY_OPEN)
return result;
tty = arg0;
/* If it's not opened, we allow. */
if ((tty->t_state & TS_ISOPEN) == 0)
result = KAUTH_RESULT_ALLOW;
else {
/*
* If it's opened, we can only allow if it's not exclusively
* opened; otherwise, that's a privileged operation and we
* let the secmodel handle it.
*/
if ((tty->t_state & TS_XCLUDE) == 0)
result = KAUTH_RESULT_ALLOW;
}
return result;
}
/*
* Initialize the tty subsystem.
*/
void
tty_init(void)
{
/*
* Send a signal from a tty to its process group or session leader.
* Handoff to the target is deferred to a soft interrupt.
*/
void
ttysig(struct tty *tp, enum ttysigtype st, int sig)
{
sigset_t *sp;
/* XXXSMP not yet KASSERT(mutex_owned(&tty_lock)); */
sp = &tp->t_sigs[st];
if (sigismember(sp, sig))
return;
sigaddset(sp, sig);
if (tp->t_sigcount++ == 0)
TAILQ_INSERT_TAIL(&tty_sigqueue, tp, t_sigqueue);
softint_schedule(tty_sigsih);
}
/*
* Deliver deferred signals from ttys. Note that the process groups
* and sessions associated with the ttys may have changed from when
* the signal was originally sent, but in practice it should not matter.
* For signals produced as a result of a syscall, the soft interrupt
* will fire before the syscall returns to the user.
*/
static void
ttysigintr(void *cookie)
{
struct tty *tp;
enum ttysigtype st;
struct pgrp *pgrp;
struct session *sess;
int sig, lflag;
char infobuf[200];
mutex_enter(&proc_lock);
mutex_spin_enter(&tty_lock);
while ((tp = TAILQ_FIRST(&tty_sigqueue)) != NULL) {
KASSERT(tp->t_sigcount > 0);
for (st = TTYSIG_PG1; st < TTYSIG_COUNT; st++) {
if ((sig = firstsig(&tp->t_sigs[st])) != 0)
break;
}
KASSERT(st < TTYSIG_COUNT);
sigdelset(&tp->t_sigs[st], sig);
if (--tp->t_sigcount == 0)
TAILQ_REMOVE(&tty_sigqueue, tp, t_sigqueue);
pgrp = tp->t_pgrp;
sess = tp->t_session;
lflag = tp->t_lflag;
if (sig == SIGINFO) {
if (ISSET(tp->t_state, TS_SIGINFO)) {
/* Via ioctl: ignore tty option. */
tp->t_state &= ~TS_SIGINFO;
lflag |= ISIG;
}
if (!ISSET(lflag, NOKERNINFO)) {
mutex_spin_exit(&tty_lock);
ttygetinfo(tp, 1, infobuf, sizeof(infobuf));
mutex_spin_enter(&tty_lock);
ttyputinfo(tp, infobuf);
}
if (!ISSET(lflag, ISIG))
continue;
}
mutex_spin_exit(&tty_lock);
KASSERT(sig != 0);
switch (st) {
case TTYSIG_PG1:
if (pgrp != NULL)
pgsignal(pgrp, sig, 1);
break;
case TTYSIG_PG2:
if (pgrp != NULL)
pgsignal(pgrp, sig, sess != NULL);
break;
case TTYSIG_LEADER:
if (sess != NULL && sess->s_leader != NULL)
psignal(sess->s_leader, sig);
break;
default:
/* NOTREACHED */
break;
}
mutex_spin_enter(&tty_lock);
}
mutex_spin_exit(&tty_lock);
mutex_exit(&proc_lock);
}
