[openssh.git] / sshpty.c

/*
 * Author: Tatu Ylonen <ylo@cs.hut.fi>
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 * Allocating a pseudo-terminal, and making it the controlling tty.
 *
 * As far as I am concerned, the code I have written for this software
 * can be used freely for any purpose.  Any derived versions of this
 * software must be clearly marked as such, and if the derived work is
 * incompatible with the protocol description in the RFC file, it must be
 * called by a name other than "ssh" or "Secure Shell".
 */

#include "includes.h"
RCSID("$OpenBSD: sshpty.c,v 1.2 2001/07/18 21:10:43 markus Exp $");

#ifdef HAVE_UTIL_H
# include <util.h>
#endif /* HAVE_UTIL_H */

#include "sshpty.h"
#include "log.h"
#include "misc.h"

/* Pty allocated with _getpty gets broken if we do I_PUSH:es to it. */
#if defined(HAVE__GETPTY) || defined(HAVE_OPENPTY)
#undef HAVE_DEV_PTMX
#endif

#ifdef HAVE_PTY_H
# include <pty.h>
#endif
#if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H)
# include <sys/stropts.h>
#endif

#ifndef O_NOCTTY
#define O_NOCTTY 0
#endif

/*
 * Allocates and opens a pty.  Returns 0 if no pty could be allocated, or
 * nonzero if a pty was successfully allocated.  On success, open file
 * descriptors for the pty and tty sides and the name of the tty side are
 * returned (the buffer must be able to hold at least 64 characters).
 */

int
pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen)
{
#if defined(HAVE_OPENPTY) || defined(BSD4_4)
	/* openpty(3) exists in OSF/1 and some other os'es */
	char *name;
	int i;

	i = openpty(ptyfd, ttyfd, NULL, NULL, NULL);
	if (i < 0) {
		error("openpty: %.100s", strerror(errno));
		return 0;
	}
	name = ttyname(*ttyfd);
	if (!name)
		fatal("openpty returns device for which ttyname fails.");

	strlcpy(namebuf, name, namebuflen);	/* possible truncation */
	return 1;
#else /* HAVE_OPENPTY */
#ifdef HAVE__GETPTY
	/*
	 * _getpty(3) exists in SGI Irix 4.x, 5.x & 6.x -- it generates more
	 * pty's automagically when needed
	 */
	char *slave;

	slave = _getpty(ptyfd, O_RDWR, 0622, 0);
	if (slave == NULL) {
		error("_getpty: %.100s", strerror(errno));
		return 0;
	}
	strlcpy(namebuf, slave, namebuflen);
	/* Open the slave side. */
	*ttyfd = open(namebuf, O_RDWR | O_NOCTTY);
	if (*ttyfd < 0) {
		error("%.200s: %.100s", namebuf, strerror(errno));
		close(*ptyfd);
		return 0;
	}
	return 1;
#else /* HAVE__GETPTY */
#if defined(HAVE_DEV_PTMX)
	/*
	 * This code is used e.g. on Solaris 2.x.  (Note that Solaris 2.3
	 * also has bsd-style ptys, but they simply do not work.)
	 */
	int ptm;
	char *pts;
	mysig_t old_signal;

	ptm = open("/dev/ptmx", O_RDWR | O_NOCTTY);
	if (ptm < 0) {
		error("/dev/ptmx: %.100s", strerror(errno));
		return 0;
	}
	old_signal = mysignal(SIGCHLD, SIG_DFL);
	if (grantpt(ptm) < 0) {
		error("grantpt: %.100s", strerror(errno));
		return 0;
	}
	mysignal(SIGCHLD, old_signal);
	if (unlockpt(ptm) < 0) {
		error("unlockpt: %.100s", strerror(errno));
		return 0;
	}
	pts = ptsname(ptm);
	if (pts == NULL)
		error("Slave pty side name could not be obtained.");
	strlcpy(namebuf, pts, namebuflen);
	*ptyfd = ptm;

	/* Open the slave side. */
	*ttyfd = open(namebuf, O_RDWR | O_NOCTTY);
	if (*ttyfd < 0) {
		error("%.100s: %.100s", namebuf, strerror(errno));
		close(*ptyfd);
		return 0;
	}
#ifndef HAVE_CYGWIN
	/*
	 * Push the appropriate streams modules, as described in Solaris pts(7).
	 * HP-UX pts(7) doesn't have ttcompat module.
	 */
	if (ioctl(*ttyfd, I_PUSH, "ptem") < 0)
		error("ioctl I_PUSH ptem: %.100s", strerror(errno));
	if (ioctl(*ttyfd, I_PUSH, "ldterm") < 0)
		error("ioctl I_PUSH ldterm: %.100s", strerror(errno));
#ifndef __hpux
	if (ioctl(*ttyfd, I_PUSH, "ttcompat") < 0)
		error("ioctl I_PUSH ttcompat: %.100s", strerror(errno));
#endif
#endif
	return 1;
#else /* HAVE_DEV_PTMX */
#ifdef HAVE_DEV_PTS_AND_PTC
	/* AIX-style pty code. */
	const char *name;

	*ptyfd = open("/dev/ptc", O_RDWR | O_NOCTTY);
	if (*ptyfd < 0) {
		error("Could not open /dev/ptc: %.100s", strerror(errno));
		return 0;
	}
	name = ttyname(*ptyfd);
	if (!name)
		fatal("Open of /dev/ptc returns device for which ttyname fails.");
	strlcpy(namebuf, name, namebuflen);
	*ttyfd = open(name, O_RDWR | O_NOCTTY);
	if (*ttyfd < 0) {
		error("Could not open pty slave side %.100s: %.100s",
		      name, strerror(errno));
		close(*ptyfd);
		return 0;
	}
	return 1;
#else /* HAVE_DEV_PTS_AND_PTC */
	/* BSD-style pty code. */
	char buf[64];
	int i;
	const char *ptymajors = "pqrstuvwxyzabcdefghijklmnoABCDEFGHIJKLMNOPQRSTUVWXYZ";
	const char *ptyminors = "0123456789abcdef";
	int num_minors = strlen(ptyminors);
	int num_ptys = strlen(ptymajors) * num_minors;

	for (i = 0; i < num_ptys; i++) {
		snprintf(buf, sizeof buf, "/dev/pty%c%c", ptymajors[i / num_minors],
			 ptyminors[i % num_minors]);
		snprintf(namebuf, namebuflen, "/dev/tty%c%c",
		    ptymajors[i / num_minors], ptyminors[i % num_minors]);

		*ptyfd = open(buf, O_RDWR | O_NOCTTY);
		if (*ptyfd < 0) {
			/* Try SCO style naming */
			snprintf(buf, sizeof buf, "/dev/ptyp%d", i);
			snprintf(namebuf, namebuflen, "/dev/ttyp%d", i);
			*ptyfd = open(buf, O_RDWR | O_NOCTTY);
			if (*ptyfd < 0)
				continue;
		}

		/* Open the slave side. */
		*ttyfd = open(namebuf, O_RDWR | O_NOCTTY);
		if (*ttyfd < 0) {
			error("%.100s: %.100s", namebuf, strerror(errno));
			close(*ptyfd);
			return 0;
		}
		return 1;
	}
	return 0;
#endif /* HAVE_DEV_PTS_AND_PTC */
#endif /* HAVE_DEV_PTMX */
#endif /* HAVE__GETPTY */
#endif /* HAVE_OPENPTY */
}

/* Releases the tty.  Its ownership is returned to root, and permissions to 0666. */

void
pty_release(const char *ttyname)
{
	if (chown(ttyname, (uid_t) 0, (gid_t) 0) < 0)
		error("chown %.100s 0 0 failed: %.100s", ttyname, strerror(errno));
	if (chmod(ttyname, (mode_t) 0666) < 0)
		error("chmod %.100s 0666 failed: %.100s", ttyname, strerror(errno));
}

/* Makes the tty the processes controlling tty and sets it to sane modes. */

void
pty_make_controlling_tty(int *ttyfd, const char *ttyname)
{
	int fd;
#ifdef USE_VHANGUP
	void *old;
#endif /* USE_VHANGUP */

	/* First disconnect from the old controlling tty. */
#ifdef TIOCNOTTY
	fd = open(_PATH_TTY, O_RDWR | O_NOCTTY);
	if (fd >= 0) {
		(void) ioctl(fd, TIOCNOTTY, NULL);
		close(fd);
	}
#endif /* TIOCNOTTY */
	if (setsid() < 0)
		error("setsid: %.100s", strerror(errno));

	/*
	 * Verify that we are successfully disconnected from the controlling
	 * tty.
	 */
	fd = open(_PATH_TTY, O_RDWR | O_NOCTTY);
	if (fd >= 0) {
		error("Failed to disconnect from controlling tty.");
		close(fd);
	}
	/* Make it our controlling tty. */
#ifdef TIOCSCTTY
	debug("Setting controlling tty using TIOCSCTTY.");
	if (ioctl(*ttyfd, TIOCSCTTY, NULL) < 0)
		error("ioctl(TIOCSCTTY): %.100s", strerror(errno));
#endif /* TIOCSCTTY */
#ifdef HAVE_NEWS4
	if (setpgrp(0,0) < 0)
		error("SETPGRP %s",strerror(errno));
#endif /* HAVE_NEWS4 */
#ifdef USE_VHANGUP
	old = signal(SIGHUP, SIG_IGN);
	vhangup();
	signal(SIGHUP, old);
#endif /* USE_VHANGUP */
	fd = open(ttyname, O_RDWR);
	if (fd < 0) {
		error("%.100s: %.100s", ttyname, strerror(errno));
	} else {
#ifdef USE_VHANGUP
		close(*ttyfd);
		*ttyfd = fd;
#else /* USE_VHANGUP */
		close(fd);
#endif /* USE_VHANGUP */
	}
	/* Verify that we now have a controlling tty. */
	fd = open(_PATH_TTY, O_WRONLY);
	if (fd < 0)
		error("open /dev/tty failed - could not set controlling tty: %.100s",
		      strerror(errno));
	else {
		close(fd);
	}
}

/* Changes the window size associated with the pty. */

void
pty_change_window_size(int ptyfd, int row, int col,
		       int xpixel, int ypixel)
{
	struct winsize w;
	w.ws_row = row;
	w.ws_col = col;
	w.ws_xpixel = xpixel;
	w.ws_ypixel = ypixel;
	(void) ioctl(ptyfd, TIOCSWINSZ, &w);
}

void
pty_setowner(struct passwd *pw, const char *ttyname)
{
	struct group *grp;
	gid_t gid;
	mode_t mode;
	struct stat st;

	/* Determine the group to make the owner of the tty. */
	grp = getgrnam("tty");
	if (grp) {
		gid = grp->gr_gid;
		mode = S_IRUSR | S_IWUSR | S_IWGRP;
	} else {
		gid = pw->pw_gid;
		mode = S_IRUSR | S_IWUSR | S_IWGRP | S_IWOTH;
	}

	/*
	 * Change owner and mode of the tty as required.
	 * Warn but continue if filesystem is read-only and the uids match.
	 */
	if (stat(ttyname, &st))
		fatal("stat(%.100s) failed: %.100s", ttyname,
		    strerror(errno));

	if (st.st_uid != pw->pw_uid || st.st_gid != gid) {
		if (chown(ttyname, pw->pw_uid, gid) < 0) {
			if (errno == EROFS && 
			   (st.st_uid == pw->pw_uid || st.st_uid == 0))
				error("chown(%.100s, %d, %d) failed: %.100s",
				      ttyname, pw->pw_uid, gid,
				      strerror(errno));
			else
				fatal("chown(%.100s, %d, %d) failed: %.100s",
				      ttyname, pw->pw_uid, gid,
				      strerror(errno));
		}
	}

	if ((st.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO)) != mode) {
		if (chmod(ttyname, mode) < 0) {
			if (errno == EROFS &&
			    (st.st_mode & (S_IRGRP | S_IROTH)) == 0)
				error("chmod(%.100s, 0%o) failed: %.100s",
				      ttyname, mode, strerror(errno));
			else
				fatal("chmod(%.100s, 0%o) failed: %.100s",
				      ttyname, mode, strerror(errno));
		}
	}
}
Commit	Line	Data
8efc0c15	1	/*
5260325f	2	* Author: Tatu Ylonen <ylo@cs.hut.fi>
5260325f	3	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5260325f	4	* All rights reserved
5260325f	5	* Allocating a pseudo-terminal, and making it the controlling tty.
6ae2364d	6	*
bcbf86ec	7	* As far as I am concerned, the code I have written for this software
	8	* can be used freely for any purpose. Any derived versions of this
	9	* software must be clearly marked as such, and if the derived work is
	10	* incompatible with the protocol description in the RFC file, it must be
	11	* called by a name other than "ssh" or "Secure Shell".
5260325f	12	*/
8efc0c15	13
8efc0c15	14	#include "includes.h"
7458aff1	15	RCSID("$OpenBSD: sshpty.c,v 1.2 2001/07/18 21:10:43 markus Exp $");
8efc0c15	16
884bcb37	17	#ifdef HAVE_UTIL_H
	18	# include <util.h>
	19	#endif /* HAVE_UTIL_H */
	20
1729c161	21	#include "sshpty.h"
42f11eb2	22	#include "log.h"
5ad9f968	23	#include "misc.h"
5260325f	24
8efc0c15	25	/* Pty allocated with _getpty gets broken if we do I_PUSH:es to it. */
	26	#if defined(HAVE__GETPTY) \|\| defined(HAVE_OPENPTY)
	27	#undef HAVE_DEV_PTMX
	28	#endif
	29
6d8c4ea4	30	#ifdef HAVE_PTY_H
	31	# include <pty.h>
	32	#endif
	33	#if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H)
	34	# include <sys/stropts.h>
	35	#endif
	36
8efc0c15	37	#ifndef O_NOCTTY
	38	#define O_NOCTTY 0
	39	#endif
	40
aa3378df	41	/*
	42	* Allocates and opens a pty. Returns 0 if no pty could be allocated, or
	43	* nonzero if a pty was successfully allocated. On success, open file
	44	* descriptors for the pty and tty sides and the name of the tty side are
	45	* returned (the buffer must be able to hold at least 64 characters).
	46	*/
8efc0c15	47
6ae2364d	48	int
a408af76	49	pty_allocate(int ptyfd, int ttyfd, char *namebuf, int namebuflen)
8efc0c15	50	{
a408af76	51	#if defined(HAVE_OPENPTY) \|\| defined(BSD4_4)
5260325f	52	/* openpty(3) exists in OSF/1 and some other os'es */
b82f1310	53	char *name;
5260325f	54	int i;
8efc0c15	55
b82f1310	56	i = openpty(ptyfd, ttyfd, NULL, NULL, NULL);
5260325f	57	if (i < 0) {
	58	error("openpty: %.100s", strerror(errno));
	59	return 0;
	60	}
b82f1310	61	name = ttyname(*ttyfd);
	62	if (!name)
	63	fatal("openpty returns device for which ttyname fails.");
	64
	65	strlcpy(namebuf, name, namebuflen); /* possible truncation */
5260325f	66	return 1;
8efc0c15	67	#else /* HAVE_OPENPTY */
8efc0c15	68	#ifdef HAVE__GETPTY
aa3378df	69	/*
	70	* _getpty(3) exists in SGI Irix 4.x, 5.x & 6.x -- it generates more
	71	* pty's automagically when needed
	72	*/
5260325f	73	char *slave;
	74
	75	slave = _getpty(ptyfd, O_RDWR, 0622, 0);
	76	if (slave == NULL) {
	77	error("_getpty: %.100s", strerror(errno));
	78	return 0;
	79	}
a408af76	80	strlcpy(namebuf, slave, namebuflen);
5260325f	81	/* Open the slave side. */
	82	*ttyfd = open(namebuf, O_RDWR \| O_NOCTTY);
	83	if (*ttyfd < 0) {
	84	error("%.200s: %.100s", namebuf, strerror(errno));
	85	close(*ptyfd);
	86	return 0;
	87	}
	88	return 1;
8efc0c15	89	#else /* HAVE__GETPTY */
a7effaac	90	#if defined(HAVE_DEV_PTMX)
aa3378df	91	/*
	92	* This code is used e.g. on Solaris 2.x. (Note that Solaris 2.3
	93	* also has bsd-style ptys, but they simply do not work.)
	94	*/
5260325f	95	int ptm;
5260325f	96	char *pts;
5ad9f968	97	mysig_t old_signal;
5260325f	98
	99	ptm = open("/dev/ptmx", O_RDWR \| O_NOCTTY);
	100	if (ptm < 0) {
	101	error("/dev/ptmx: %.100s", strerror(errno));
	102	return 0;
	103	}
5ad9f968	104	old_signal = mysignal(SIGCHLD, SIG_DFL);
5260325f	105	if (grantpt(ptm) < 0) {
	106	error("grantpt: %.100s", strerror(errno));
	107	return 0;
	108	}
5ad9f968	109	mysignal(SIGCHLD, old_signal);
5260325f	110	if (unlockpt(ptm) < 0) {
	111	error("unlockpt: %.100s", strerror(errno));
	112	return 0;
	113	}
	114	pts = ptsname(ptm);
	115	if (pts == NULL)
	116	error("Slave pty side name could not be obtained.");
a408af76	117	strlcpy(namebuf, pts, namebuflen);
5260325f	118	*ptyfd = ptm;
	119
	120	/* Open the slave side. */
	121	*ttyfd = open(namebuf, O_RDWR \| O_NOCTTY);
	122	if (*ttyfd < 0) {
	123	error("%.100s: %.100s", namebuf, strerror(errno));
	124	close(*ptyfd);
	125	return 0;
	126	}
3c62e7eb	127	#ifndef HAVE_CYGWIN
96054e6f	128	/*
	129	* Push the appropriate streams modules, as described in Solaris pts(7).
	130	* HP-UX pts(7) doesn't have ttcompat module.
	131	*/
5260325f	132	if (ioctl(*ttyfd, I_PUSH, "ptem") < 0)
	133	error("ioctl I_PUSH ptem: %.100s", strerror(errno));
	134	if (ioctl(*ttyfd, I_PUSH, "ldterm") < 0)
	135	error("ioctl I_PUSH ldterm: %.100s", strerror(errno));
96054e6f	136	#ifndef __hpux
5260325f	137	if (ioctl(*ttyfd, I_PUSH, "ttcompat") < 0)
5260325f	138	error("ioctl I_PUSH ttcompat: %.100s", strerror(errno));
3c62e7eb	139	#endif
be48d23c	140	#endif
5260325f	141	return 1;
8efc0c15	142	#else /* HAVE_DEV_PTMX */
8efc0c15	143	#ifdef HAVE_DEV_PTS_AND_PTC
5260325f	144	/* AIX-style pty code. */
5260325f	145	const char *name;
8efc0c15	146
5260325f	147	*ptyfd = open("/dev/ptc", O_RDWR \| O_NOCTTY);
	148	if (*ptyfd < 0) {
	149	error("Could not open /dev/ptc: %.100s", strerror(errno));
	150	return 0;
	151	}
	152	name = ttyname(*ptyfd);
	153	if (!name)
	154	fatal("Open of /dev/ptc returns device for which ttyname fails.");
a408af76	155	strlcpy(namebuf, name, namebuflen);
5260325f	156	*ttyfd = open(name, O_RDWR \| O_NOCTTY);
	157	if (*ttyfd < 0) {
	158	error("Could not open pty slave side %.100s: %.100s",
	159	name, strerror(errno));
	160	close(*ptyfd);
	161	return 0;
	162	}
	163	return 1;
8efc0c15	164	#else /* HAVE_DEV_PTS_AND_PTC */
5260325f	165	/* BSD-style pty code. */
	166	char buf[64];
	167	int i;
aa3378df	168	const char *ptymajors = "pqrstuvwxyzabcdefghijklmnoABCDEFGHIJKLMNOPQRSTUVWXYZ";
5260325f	169	const char *ptyminors = "0123456789abcdef";
	170	int num_minors = strlen(ptyminors);
	171	int num_ptys = strlen(ptymajors) * num_minors;
	172
	173	for (i = 0; i < num_ptys; i++) {
	174	snprintf(buf, sizeof buf, "/dev/pty%c%c", ptymajors[i / num_minors],
	175	ptyminors[i % num_minors]);
95f1eccc	176	snprintf(namebuf, namebuflen, "/dev/tty%c%c",
a408af76	177	ptymajors[i / num_minors], ptyminors[i % num_minors]);
5260325f	178
b5f90139	179	*ptyfd = open(buf, O_RDWR \| O_NOCTTY);
	180	if (*ptyfd < 0) {
	181	/* Try SCO style naming */
	182	snprintf(buf, sizeof buf, "/dev/ptyp%d", i);
	183	snprintf(namebuf, namebuflen, "/dev/ttyp%d", i);
	184	*ptyfd = open(buf, O_RDWR \| O_NOCTTY);
	185	if (*ptyfd < 0)
	186	continue;
2b87da3b	187	}
2b87da3b	188
5260325f	189	/* Open the slave side. */
	190	*ttyfd = open(namebuf, O_RDWR \| O_NOCTTY);
	191	if (*ttyfd < 0) {
	192	error("%.100s: %.100s", namebuf, strerror(errno));
	193	close(*ptyfd);
	194	return 0;
	195	}
	196	return 1;
8efc0c15	197	}
5260325f	198	return 0;
8efc0c15	199	#endif /* HAVE_DEV_PTS_AND_PTC */
	200	#endif /* HAVE_DEV_PTMX */
	201	#endif /* HAVE__GETPTY */
	202	#endif /* HAVE_OPENPTY */
	203	}
	204
5260325f	205	/* Releases the tty. Its ownership is returned to root, and permissions to 0666. */
8efc0c15	206
6ae2364d	207	void
5260325f	208	pty_release(const char *ttyname)
8efc0c15	209	{
3276571c	210	if (chown(ttyname, (uid_t) 0, (gid_t) 0) < 0)
817175bc	211	error("chown %.100s 0 0 failed: %.100s", ttyname, strerror(errno));
3276571c	212	if (chmod(ttyname, (mode_t) 0666) < 0)
817175bc	213	error("chmod %.100s 0666 failed: %.100s", ttyname, strerror(errno));
8efc0c15	214	}
	215
	216	/* Makes the tty the processes controlling tty and sets it to sane modes. */
	217
6ae2364d	218	void
5260325f	219	pty_make_controlling_tty(int ttyfd, const char ttyname)
8efc0c15	220	{
5260325f	221	int fd;
3c62e7eb	222	#ifdef USE_VHANGUP
4e577b89	223	void *old;
3c62e7eb	224	#endif /* USE_VHANGUP */
8efc0c15	225
5260325f	226	/* First disconnect from the old controlling tty. */
8efc0c15	227	#ifdef TIOCNOTTY
5ca51e19	228	fd = open(_PATH_TTY, O_RDWR \| O_NOCTTY);
5260325f	229	if (fd >= 0) {
	230	(void) ioctl(fd, TIOCNOTTY, NULL);
	231	close(fd);
	232	}
8efc0c15	233	#endif /* TIOCNOTTY */
5260325f	234	if (setsid() < 0)
	235	error("setsid: %.100s", strerror(errno));
	236
aa3378df	237	/*
	238	* Verify that we are successfully disconnected from the controlling
	239	* tty.
	240	*/
5ca51e19	241	fd = open(_PATH_TTY, O_RDWR \| O_NOCTTY);
5260325f	242	if (fd >= 0) {
	243	error("Failed to disconnect from controlling tty.");
	244	close(fd);
	245	}
	246	/* Make it our controlling tty. */
8efc0c15	247	#ifdef TIOCSCTTY
5260325f	248	debug("Setting controlling tty using TIOCSCTTY.");
a3bf38d0	249	if (ioctl(*ttyfd, TIOCSCTTY, NULL) < 0)
a3bf38d0	250	error("ioctl(TIOCSCTTY): %.100s", strerror(errno));
8efc0c15	251	#endif /* TIOCSCTTY */
66d6c27e	252	#ifdef HAVE_NEWS4
	253	if (setpgrp(0,0) < 0)
	254	error("SETPGRP %s",strerror(errno));
	255	#endif /* HAVE_NEWS4 */
3c62e7eb	256	#ifdef USE_VHANGUP
4e577b89	257	old = signal(SIGHUP, SIG_IGN);
	258	vhangup();
	259	signal(SIGHUP, old);
3c62e7eb	260	#endif /* USE_VHANGUP */
5260325f	261	fd = open(ttyname, O_RDWR);
4e577b89	262	if (fd < 0) {
5260325f	263	error("%.100s: %.100s", ttyname, strerror(errno));
4e577b89	264	} else {
3c62e7eb	265	#ifdef USE_VHANGUP
4e577b89	266	close(*ttyfd);
4e577b89	267	*ttyfd = fd;
3c62e7eb	268	#else /* USE_VHANGUP */
5260325f	269	close(fd);
3c62e7eb	270	#endif /* USE_VHANGUP */
4e577b89	271	}
5260325f	272	/* Verify that we now have a controlling tty. */
5ca51e19	273	fd = open(_PATH_TTY, O_WRONLY);
5260325f	274	if (fd < 0)
	275	error("open /dev/tty failed - could not set controlling tty: %.100s",
	276	strerror(errno));
	277	else {
	278	close(fd);
	279	}
8efc0c15	280	}
	281
	282	/* Changes the window size associated with the pty. */
	283
6ae2364d	284	void
5260325f	285	pty_change_window_size(int ptyfd, int row, int col,
5260325f	286	int xpixel, int ypixel)
8efc0c15	287	{
5260325f	288	struct winsize w;
	289	w.ws_row = row;
	290	w.ws_col = col;
	291	w.ws_xpixel = xpixel;
	292	w.ws_ypixel = ypixel;
	293	(void) ioctl(ptyfd, TIOCSWINSZ, &w);
8efc0c15	294	}
817175bc	295
	296	void
	297	pty_setowner(struct passwd pw, const char ttyname)
	298	{
	299	struct group *grp;
	300	gid_t gid;
	301	mode_t mode;
227e8e86	302	struct stat st;
817175bc	303
	304	/* Determine the group to make the owner of the tty. */
	305	grp = getgrnam("tty");
	306	if (grp) {
	307	gid = grp->gr_gid;
	308	mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
	309	} else {
	310	gid = pw->pw_gid;
	311	mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
	312	}
	313
227e8e86	314	/*
	315	* Change owner and mode of the tty as required.
	316	* Warn but continue if filesystem is read-only and the uids match.
	317	*/
	318	if (stat(ttyname, &st))
	319	fatal("stat(%.100s) failed: %.100s", ttyname,
	320	strerror(errno));
	321
	322	if (st.st_uid != pw->pw_uid \|\| st.st_gid != gid) {
	323	if (chown(ttyname, pw->pw_uid, gid) < 0) {
7458aff1	324	if (errno == EROFS &&
7458aff1	325	(st.st_uid == pw->pw_uid \|\| st.st_uid == 0))
227e8e86	326	error("chown(%.100s, %d, %d) failed: %.100s",
2b87da3b	327	ttyname, pw->pw_uid, gid,
227e8e86	328	strerror(errno));
	329	else
	330	fatal("chown(%.100s, %d, %d) failed: %.100s",
2b87da3b	331	ttyname, pw->pw_uid, gid,
227e8e86	332	strerror(errno));
	333	}
	334	}
	335
	336	if ((st.st_mode & (S_IRWXU\|S_IRWXG\|S_IRWXO)) != mode) {
	337	if (chmod(ttyname, mode) < 0) {
	338	if (errno == EROFS &&
	339	(st.st_mode & (S_IRGRP \| S_IROTH)) == 0)
	340	error("chmod(%.100s, 0%o) failed: %.100s",
	341	ttyname, mode, strerror(errno));
	342	else
	343	fatal("chmod(%.100s, 0%o) failed: %.100s",
	344	ttyname, mode, strerror(errno));
	345	}
	346	}
817175bc	347	}