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#include <unistd.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <signal.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
#include <stdarg.h>
#include <string.h>
#include <termios.h>
#include <pty.h>
#include "pterm.h"
#include "log.h"
#ifndef _PATH_TTY
#define _PATH_TTY "/dev/tty"
#endif
#ifndef O_NOCTTY
#define O_NOCTTY 0
#endif
int
pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
{
/* 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) {
E_STRERR("%s", "Allocate pseudo terminal");
return 1;
}
name = ttyname(*ttyfd);
if (!name) {
E_STRERR("%s", "Invalid ttyname for pseudo terminal");
abort();
}
strncpy(namebuf, name, namebuflen); /* possible truncation */
return 0;
}
void
pty_release(const char *tty)
{
if (chown(tty, (uid_t) 0, (gid_t) 0) < 0) {
E_STRERR("Change tty owner for '%s'", tty);
}
if (chmod(tty, (mode_t) 0666) < 0) {
E_STRERR("Change tty mode for '%s'", tty);
}
}
void
pty_make_controlling_tty(int *ttyfd, const char *tty)
{
int fd;
/* First disconnect from the old controlling tty. */
fd = open(_PATH_TTY, O_RDWR | O_NOCTTY);
if (fd >= 0) {
(void) ioctl(fd, TIOCNOTTY, NULL);
close(fd);
}
if (setsid() < 0)
E_STRERR("%s", "New session");
/*
* Verify that we are successfully disconnected from the controlling
* tty.
*/
fd = open(_PATH_TTY, O_RDWR | O_NOCTTY);
if (fd >= 0) {
E2("%s", "Failed to disconnect from controlling tty.");
close(fd);
}
/* Make it our controlling tty. */
D("%s", "Setting controlling tty using TIOCSCTTY.");
if (ioctl(*ttyfd, TIOCSCTTY, NULL) < 0)
E_STRERR("%s", "ioctl(TIOCSCTTY)");
if (setpgrp() < 0)
E_STRERR("%s", "Set new process group");
fd = open(tty, O_RDWR);
if (fd < 0)
E_STRERR("Open tty '%s'", tty);
else
close(fd);
/* Verify that we now have a controlling tty. */
fd = open(_PATH_TTY, O_WRONLY);
if (fd < 0)
E_STRERR("Could not set controlling tty - Open '%s'", tty);
else
close(fd);
}
/* Changes the window size associated with the pty. */
void
pty_change_window_size(int ptyfd, unsigned int row,
unsigned int col,
unsigned int xpixel,
unsigned int ypixel)
{
struct winsize w;
/* may truncate unsigned int -> unsigned short */
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 *tty)
{
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");
gid = (grp != NULL) ? grp->gr_gid : pw->pw_gid;
mode = (grp != NULL) ? 0620 : 0600;
/*
* Change owner and mode of the tty as required.
* Warn but continue if filesystem is read-only and the uids match/
* tty is owned by root.
*/
if (stat(tty, &st))
FATAL("Change owner of %s", tty);
#ifdef WITH_SELINUX
ssh_selinux_setup_pty(pw->pw_name, tty);
#endif
if (st.st_uid != pw->pw_uid || st.st_gid != gid) {
if (chown(tty, pw->pw_uid, gid) < 0) {
if (errno == EROFS &&
(st.st_uid == pw->pw_uid || st.st_uid == 0))
{
D("Change owner of '%s' to %u:%u",
tty, (unsigned) pw->pw_uid,
(unsigned) gid);
} else {
FATAL("Change owner of '%s' to %u:%u",
tty, (unsigned) pw->pw_uid,
(unsigned) gid);
}
}
}
if ((st.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO)) != mode) {
if (chmod(tty, mode) < 0) {
if (errno == EROFS &&
(st.st_mode & (S_IRGRP | S_IROTH)) == 0)
{
D("Change mode of '%s' to 0%o",
tty, (unsigned) mode);
} else {
FATAL("Change mode of '%s' to 0%o",
tty, (unsigned) mode);
}
}
}
}
/* Disconnect from the controlling tty. */
void
disconnect_controlling_tty(void)
{
int fd;
if ((fd = open(_PATH_TTY, O_RDWR | O_NOCTTY)) >= 0) {
(void) ioctl(fd, TIOCNOTTY, NULL);
close(fd);
}
}
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