libptytty/src/ptytty.C

/*--------------------------------*-C-*---------------------------------*
 * File:        ptytty.C
 *----------------------------------------------------------------------*
 *
 * All portions of code are copyright by their respective author/s.
 * Copyright (c) 1999-2001 Geoff Wing <gcw@pobox.com>
 * Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *---------------------------------------------------------------------*/

#include "../config.h"          /* NECESSARY */

#include <cstdlib>
#include <cstring>

#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <fcntl.h>

#ifdef HAVE_SYS_IOCTL_H
# include <sys/ioctl.h>
#endif
#if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H)
# include <sys/stropts.h>      /* for I_PUSH */
#endif
#ifdef HAVE_ISASTREAM
# include <stropts.h>
#endif
#if defined(HAVE_PTY_H)
# include <pty.h>
#elif defined(HAVE_LIBUTIL_H)
# include <libutil.h>
#elif defined(HAVE_UTIL_H)
# include <util.h>
#endif
#ifdef TTY_GID_SUPPORT
#include <grp.h>
#endif

#include <cstdio>

#include "rxvtutil.h"
#include "fdpass.h"
#include "ptytty.h"

/////////////////////////////////////////////////////////////////////////////

/* ------------------------------------------------------------------------- *
 *                  GET PSEUDO TELETYPE - MASTER AND SLAVE                   *
 * ------------------------------------------------------------------------- */
/*
 * Returns pty file descriptor, or -1 on failure 
 * If successful, ttydev is set to the name of the slave device.
 * fd_tty _may_ also be set to an open fd to the slave device
 */
#if defined(UNIX98_PTY)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

# if defined(HAVE_GETPT)
  pfd = getpt();
# elif defined(HAVE_POSIX_OPENPT)
  pfd = posix_openpt (O_RDWR);
# else
  pfd = open (CLONE_DEVICE, O_RDWR | O_NOCTTY, 0);
# endif
  if (pfd >= 0)
    {
      if (grantpt (pfd) == 0    /* change slave permissions */
          && unlockpt (pfd) == 0)
        {       /* slave now unlocked */
          *ttydev = strdup (ptsname (pfd));     /* get slave's name */
          return pfd;
        }

      close (pfd);
    }

  return -1;
}
#elif defined(HAVE_OPENPTY)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;
  int res;
  char tty_name[32];
  
  res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
  if (res != -1)
    {
      *ttydev = strdup (tty_name);
      return pfd;
    }

  return -1;
}
#elif defined(HAVE__GETPTY)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

  *ttydev = _getpty (&pfd, O_RDWR | O_NONBLOCK | O_NOCTTY, 0622, 0);
  if (*ttydev != NULL)
    return pfd;

  return -1;
}
#elif defined(HAVE_DEV_PTC)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

  if ((pfd = open ("/dev/ptc", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ttyname (pfd));
      return pfd;
    }

  return -1;
}
#elif defined(HAVE_DEV_CLONE)
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

  if ((pfd = open ("/dev/ptym/clone", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ptsname (pfd));
      return pfd;
    }

  return -1;
}
#else
/* Based on the code in openssh/openbsd-compat/bsd-openpty.c */
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;
  int i;
  char pty_name[32];
  char tty_name[32];
  const char *majors = "pqrstuvwxyzabcde";
  const char *minors = "0123456789abcdef";
  for (i = 0; i < 256; i++)
    {
      snprintf(pty_name, 32, "/dev/pty%c%c", majors[i / 16], minors[i % 16]);
      snprintf(tty_name, 32, "/dev/tty%c%c", majors[i / 16], minors[i % 16]);
      if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) == -1)
        {
          snprintf(pty_name, 32, "/dev/ptyp%d", i);
          snprintf(tty_name, 32, "/dev/ttyp%d", i);
          if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) == -1)
            continue;
        }
      if (access (tty_name, R_OK | W_OK) == 0)
        {
          *ttydev = strdup (tty_name);
          return pfd;
        }

      close (pfd);
    }
}
#endif

/*----------------------------------------------------------------------*/
/*
 * Returns tty file descriptor, or -1 on failure 
 */
static int
get_tty (char *ttydev)
{
  return open (ttydev, O_RDWR | O_NOCTTY, 0);
}

/*----------------------------------------------------------------------*/
/*
 * Make our tty a controlling tty so that /dev/tty points to us
 */
static int
control_tty (int fd_tty)
{
  setsid ();

#if defined(HAVE_DEV_PTMX) && defined(I_PUSH)
  /*
   * Push STREAMS modules:
   *    ptem: pseudo-terminal hardware emulation module.
   *    ldterm: standard terminal line discipline.
   *    ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
   *
   * After we push the STREAMS modules, the first open () on the slave side
   * (i.e. the next section between the dashes giving us "tty opened OK")
   * should make the "ptem" (or "ldterm" depending upon either which OS
   * version or which set of manual pages you have) module give us a
   * controlling terminal.  We must already have close ()d the master side
   * fd in this child process before we push STREAMS modules on because the
   * documentation is really unclear about whether it is any close () on
   * the master side or the last close () - i.e. a proper STREAMS dismantling
   * close () - on the master side which causes a hang up to be sent
   * through - Geoff Wing
   */
# ifdef HAVE_ISASTREAM
  if (isastream (fd_tty) == 1)
# endif
    {
      ioctl (fd_tty, I_PUSH, "ptem");
      ioctl (fd_tty, I_PUSH, "ldterm");
      ioctl (fd_tty, I_PUSH, "ttcompat");
    }
#endif

  ioctl (fd_tty, TIOCSCTTY, NULL);

  int fd = open ("/dev/tty", O_WRONLY);
  if (fd < 0)
    return -1;          /* fatal */

  close (fd);

  return 0;
}

void
rxvt_ptytty::close_tty ()
{
  if (tty < 0)
    return;

  close (tty);
  tty = -1;
}

bool
rxvt_ptytty::make_controlling_tty ()
{
  return control_tty (tty) >= 0;
}

void
rxvt_ptytty::set_utf8_mode (bool on)
{
#ifdef IUTF8
  if (pty < 0)
    return;

  struct termios tio;

  if (tcgetattr (pty, &tio) != -1)
    {
      tcflag_t new_cflag = tio.c_iflag;

      if (on)
        new_cflag |= IUTF8;
      else
        new_cflag &= ~IUTF8;

      if (new_cflag != tio.c_iflag)
        {
          tio.c_iflag = new_cflag;
          tcsetattr (pty, TCSANOW, &tio);
        }
    }
#endif
}

static struct ttyconf {
  gid_t gid;
  mode_t mode;

  ttyconf ()
    {
#ifdef TTY_GID_SUPPORT
      struct group *gr = getgrnam ("tty");

      if (gr)
        {           /* change group ownership of tty to "tty" */
          mode = S_IRUSR | S_IWUSR | S_IWGRP;
          gid = gr->gr_gid;
        }
      else
#endif                          /* TTY_GID_SUPPORT */
        {
          mode = S_IRUSR | S_IWUSR | S_IWGRP | S_IWOTH;
          gid = 0;
        }
    }
} ttyconf;

rxvt_ptytty_unix::rxvt_ptytty_unix ()
{
  name = 0;
#if UTMP_SUPPORT
  cmd_pid = 0;
#endif
}

rxvt_ptytty_unix::~rxvt_ptytty_unix ()
{
#if UTMP_SUPPORT
  logout ();
#endif
  put ();
}

void
rxvt_ptytty_unix::put ()
{
  chmod (name, RESTORE_TTY_MODE);
  chown (name, 0, ttyconf.gid);

  close_tty ();

  if (pty >= 0)
    close (pty);

  free (name);

  pty = tty = -1;
  name = 0;
}

bool
rxvt_ptytty_unix::get ()
{
  /* get master (pty) */
  if ((pty = get_pty (&tty, &name)) < 0)
    return false;

  fcntl (pty, F_SETFL, O_NONBLOCK);

  /* get slave (tty) */
  if (tty < 0)
    {
#ifndef NO_SETOWNER_TTYDEV
      chown (name, getuid (), ttyconf.gid);      /* fail silently */
      chmod (name, ttyconf.mode);
# ifdef HAVE_REVOKE
      revoke (name);
# endif
#endif

      if ((tty = get_tty (name)) < 0)
        {
          put ();
          return false;
        }
    }

  return true;
}

#if PTYTTY_HELPER

static int sock_fd;
static int pid;

struct command
{
  enum { get, login, destroy } type;

  rxvt_ptytty *id;

  bool login_shell;
  int cmd_pid;
  char hostname[512]; // arbitrary, but should be plenty
};

struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
{
  rxvt_ptytty *id;

  ~rxvt_ptytty_proxy ();

  bool get ();
  void login (int cmd_pid, bool login_shell, const char *hostname);
};

bool
rxvt_ptytty_proxy::get ()
{
  command cmd;

  cmd.type = command::get;

  write (sock_fd, &cmd, sizeof (cmd));

  if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
    rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");

  if (!id)
    return false;

  if ((pty = rxvt_recv_fd (sock_fd)) < 0
      || (tty = rxvt_recv_fd (sock_fd)) < 0)
    rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");

  return true;
}

void
rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
{
  command cmd;

  cmd.type = command::login;
  cmd.id = id;
  cmd.cmd_pid = cmd_pid;
  cmd.login_shell = login_shell;
  strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));

  write (sock_fd, &cmd, sizeof (cmd));
}

rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
{
  command cmd;

  cmd.type = command::destroy;
  cmd.id = id;

  write (sock_fd, &cmd, sizeof (cmd));
}

static
void serve ()
{
  command cmd;
  vector<rxvt_ptytty *> ptys;

  while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
    {
      if (cmd.type == command::get)
        {
          // -> id ptyfd ttyfd
          cmd.id = new rxvt_ptytty_unix;

          if (cmd.id->get ())
            {
              write (sock_fd, &cmd.id, sizeof (cmd.id));
              ptys.push_back (cmd.id);

              rxvt_send_fd (sock_fd, cmd.id->pty);
              rxvt_send_fd (sock_fd, cmd.id->tty);
            }
          else
            {
              delete cmd.id;
              cmd.id = 0;
              write (sock_fd, &cmd.id, sizeof (cmd.id));
            }
        }
      else if (cmd.type == command::login)
        {
#if UTMP_SUPPORT
          if (find (ptys.begin (), ptys.end (), cmd.id))
            {
              cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
              cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
            }
#endif
        }
      else if (cmd.type == command::destroy)
        {
          rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);

          if (pty)
            {
              delete *pty;
              ptys.erase (pty);
            }
        }
      else
        break;
    }

  // destroy all ptys
  for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
    delete *i;
}

void rxvt_ptytty_server ()
{
  int sv[2];

  if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
    rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");

  pid = fork ();

  if (pid < 0)
    rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");

  if (pid)
    {
      // client, urxvt
      sock_fd = sv[0];
      close (sv[1]);
      fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
    }
  else
    {
      // server, pty-helper
      sock_fd = sv[1];

      for (int fd = 0; fd < 1023; fd++)
        if (fd != sock_fd)
          close (fd);

      serve ();
      _exit (EXIT_SUCCESS);
    }
}

#endif

// a "factory" *g*
rxvt_ptytty *
rxvt_new_ptytty ()
{
#if PTYTTY_HELPER
  if (pid > 0)
    // use helper process
    return new rxvt_ptytty_proxy;
  else
#endif
    return new rxvt_ptytty_unix;
}

/*----------------------- end-of-file (C source) -----------------------*/

Revision:	1.2
Committed:	Sat Jan 21 22:01:36 2006 UTC (18 years, 5 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.1:	+342 -267 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	/---------------------------------C----------------------------------
2			* File: ptytty.C
3			----------------------------------------------------------------------
4			*
5			* All portions of code are copyright by their respective author/s.
6			* Copyright (c) 1999-2001 Geoff Wing <gcw@pobox.com>
7	root	1.2	* Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com>
8	root	1.1	*
9			* This program is free software; you can redistribute it and/or modify
10			* it under the terms of the GNU General Public License as published by
11			* the Free Software Foundation; either version 2 of the License, or
12			* (at your option) any later version.
13			*
14			* This program is distributed in the hope that it will be useful,
15			* but WITHOUT ANY WARRANTY; without even the implied warranty of
16			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17			* GNU General Public License for more details.
18			*
19			* You should have received a copy of the GNU General Public License
20			* along with this program; if not, write to the Free Software
21			* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22			---------------------------------------------------------------------/
23
24			#include "../config.h" /* NECESSARY */
25
26	root	1.2	#include <cstdlib>
27			#include <cstring>
28
29			#include <sys/types.h>
30			#include <sys/socket.h>
31			#include <unistd.h>
32			#include <fcntl.h>
33
34	root	1.1	#ifdef HAVE_SYS_IOCTL_H
35			# include <sys/ioctl.h>
36			#endif
37	root	1.2	#if defined(HAVE_DEV_PTMX) && defined(HAVE_SYS_STROPTS_H)
38	root	1.1	# include <sys/stropts.h> /* for I_PUSH */
39			#endif
40			#ifdef HAVE_ISASTREAM
41			# include <stropts.h>
42			#endif
43	root	1.2	#if defined(HAVE_PTY_H)
44	root	1.1	# include <pty.h>
45	root	1.2	#elif defined(HAVE_LIBUTIL_H)
46	root	1.1	# include <libutil.h>
47	root	1.2	#elif defined(HAVE_UTIL_H)
48	root	1.1	# include <util.h>
49			#endif
50	root	1.2	#ifdef TTY_GID_SUPPORT
51			#include <grp.h>
52			#endif
53	root	1.1
54			#include <cstdio>
55	root	1.2
56			#include "rxvtutil.h"
57			#include "fdpass.h"
58			#include "ptytty.h"
59
60			/////////////////////////////////////////////////////////////////////////////
61	root	1.1
62			/* ------------------------------------------------------------------------- *
63			* GET PSEUDO TELETYPE - MASTER AND SLAVE *
64			* ------------------------------------------------------------------------- */
65			/*
66			* Returns pty file descriptor, or -1 on failure
67			* If successful, ttydev is set to the name of the slave device.
68			* fd_tty _may_ also be set to an open fd to the slave device
69			*/
70	root	1.2	#if defined(UNIX98_PTY)
71	root	1.1	static int
72			get_pty (int fd_tty, char *ttydev)
73			{
74			int pfd;
75
76	root	1.2	# if defined(HAVE_GETPT)
77			pfd = getpt();
78			# elif defined(HAVE_POSIX_OPENPT)
79			pfd = posix_openpt (O_RDWR);
80			# else
81			pfd = open (CLONE_DEVICE, O_RDWR \| O_NOCTTY, 0);
82			# endif
83			if (pfd >= 0)
84			{
85			if (grantpt (pfd) == 0 /* change slave permissions */
86			&& unlockpt (pfd) == 0)
87			{ /* slave now unlocked */
88			ttydev = strdup (ptsname (pfd)); / get slave's name */
89			return pfd;
90			}
91	root	1.1
92	root	1.2	close (pfd);
93			}
94
95			return -1;
96			}
97			#elif defined(HAVE_OPENPTY)
98			static int
99			get_pty (int fd_tty, char *ttydev)
100			{
101			int pfd;
102			int res;
103			char tty_name[32];
104
105			res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
106			if (res != -1)
107	root	1.1	{
108			*ttydev = strdup (tty_name);
109			return pfd;
110			}
111
112	root	1.2	return -1;
113			}
114			#elif defined(HAVE__GETPTY)
115			static int
116			get_pty (int fd_tty, char *ttydev)
117			{
118			int pfd;
119
120	root	1.1	*ttydev = _getpty (&pfd, O_RDWR \| O_NONBLOCK \| O_NOCTTY, 0622, 0);
121			if (*ttydev != NULL)
122			return pfd;
123
124	root	1.2	return -1;
125			}
126			#elif defined(HAVE_DEV_PTC)
127			static int
128			get_pty (int fd_tty, char *ttydev)
129			{
130			int pfd;
131	root	1.1
132			if ((pfd = open ("/dev/ptc", O_RDWR \| O_NOCTTY, 0)) >= 0)
133			{
134			*ttydev = strdup (ttyname (pfd));
135			return pfd;
136			}
137
138	root	1.2	return -1;
139			}
140			#elif defined(HAVE_DEV_CLONE)
141			static int
142			get_pty (int fd_tty, char *ttydev)
143			{
144			int pfd;
145
146	root	1.1	if ((pfd = open ("/dev/ptym/clone", O_RDWR \| O_NOCTTY, 0)) >= 0)
147			{
148			*ttydev = strdup (ptsname (pfd));
149			return pfd;
150			}
151
152	root	1.2	return -1;
153			}
154			#else
155			/* Based on the code in openssh/openbsd-compat/bsd-openpty.c */
156			static int
157			get_pty (int fd_tty, char *ttydev)
158			{
159			int pfd;
160			int i;
161			char pty_name[32];
162			char tty_name[32];
163			const char *majors = "pqrstuvwxyzabcde";
164			const char *minors = "0123456789abcdef";
165			for (i = 0; i < 256; i++)
166			{
167			snprintf(pty_name, 32, "/dev/pty%c%c", majors[i / 16], minors[i % 16]);
168			snprintf(tty_name, 32, "/dev/tty%c%c", majors[i / 16], minors[i % 16]);
169			if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) == -1)
170			{
171			snprintf(pty_name, 32, "/dev/ptyp%d", i);
172			snprintf(tty_name, 32, "/dev/ttyp%d", i);
173			if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) == -1)
174			continue;
175			}
176			if (access (tty_name, R_OK \| W_OK) == 0)
177			{
178			*ttydev = strdup (tty_name);
179			return pfd;
180			}
181	root	1.1
182	root	1.2	close (pfd);
183			}
184			}
185	root	1.1	#endif
186
187			/----------------------------------------------------------------------/
188			/*
189			* Returns tty file descriptor, or -1 on failure
190			*/
191			static int
192			get_tty (char *ttydev)
193			{
194			return open (ttydev, O_RDWR \| O_NOCTTY, 0);
195			}
196
197			/----------------------------------------------------------------------/
198			/*
199			* Make our tty a controlling tty so that /dev/tty points to us
200			*/
201			static int
202	root	1.2	control_tty (int fd_tty)
203	root	1.1	{
204			setsid ();
205
206	root	1.2	#if defined(HAVE_DEV_PTMX) && defined(I_PUSH)
207	root	1.1	/*
208			* Push STREAMS modules:
209			* ptem: pseudo-terminal hardware emulation module.
210			* ldterm: standard terminal line discipline.
211			* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
212			*
213			* After we push the STREAMS modules, the first open () on the slave side
214			* (i.e. the next section between the dashes giving us "tty opened OK")
215			* should make the "ptem" (or "ldterm" depending upon either which OS
216			* version or which set of manual pages you have) module give us a
217			* controlling terminal. We must already have close ()d the master side
218			* fd in this child process before we push STREAMS modules on because the
219			* documentation is really unclear about whether it is any close () on
220			* the master side or the last close () - i.e. a proper STREAMS dismantling
221			* close () - on the master side which causes a hang up to be sent
222			* through - Geoff Wing
223			*/
224			# ifdef HAVE_ISASTREAM
225			if (isastream (fd_tty) == 1)
226			# endif
227			{
228			ioctl (fd_tty, I_PUSH, "ptem");
229			ioctl (fd_tty, I_PUSH, "ldterm");
230			ioctl (fd_tty, I_PUSH, "ttcompat");
231			}
232			#endif
233	root	1.2
234			ioctl (fd_tty, TIOCSCTTY, NULL);
235
236			int fd = open ("/dev/tty", O_WRONLY);
237	root	1.1	if (fd < 0)
238			return -1; /* fatal */
239	root	1.2
240	root	1.1	close (fd);
241
242			return 0;
243			}
244
245	root	1.2	void
246			rxvt_ptytty::close_tty ()
247			{
248			if (tty < 0)
249			return;
250
251			close (tty);
252			tty = -1;
253			}
254
255			bool
256			rxvt_ptytty::make_controlling_tty ()
257			{
258			return control_tty (tty) >= 0;
259			}
260
261			void
262			rxvt_ptytty::set_utf8_mode (bool on)
263			{
264			#ifdef IUTF8
265			if (pty < 0)
266			return;
267
268			struct termios tio;
269
270			if (tcgetattr (pty, &tio) != -1)
271			{
272			tcflag_t new_cflag = tio.c_iflag;
273
274			if (on)
275			new_cflag \|= IUTF8;
276			else
277			new_cflag &= ~IUTF8;
278
279			if (new_cflag != tio.c_iflag)
280			{
281			tio.c_iflag = new_cflag;
282			tcsetattr (pty, TCSANOW, &tio);
283			}
284			}
285			#endif
286			}
287
288	root	1.1	static struct ttyconf {
289			gid_t gid;
290			mode_t mode;
291
292			ttyconf ()
293			{
294			#ifdef TTY_GID_SUPPORT
295			struct group *gr = getgrnam ("tty");
296
297			if (gr)
298			{ /* change group ownership of tty to "tty" */
299			mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
300			gid = gr->gr_gid;
301			}
302			else
303			#endif /* TTY_GID_SUPPORT */
304			{
305			mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
306	root	1.2	gid = 0;
307	root	1.1	}
308			}
309			} ttyconf;
310
311	root	1.2	rxvt_ptytty_unix::rxvt_ptytty_unix ()
312	root	1.1	{
313			name = 0;
314	root	1.2	#if UTMP_SUPPORT
315			cmd_pid = 0;
316	root	1.1	#endif
317			}
318
319	root	1.2	rxvt_ptytty_unix::~rxvt_ptytty_unix ()
320	root	1.1	{
321	root	1.2	#if UTMP_SUPPORT
322			logout ();
323			#endif
324	root	1.1	put ();
325			}
326
327			void
328	root	1.2	rxvt_ptytty_unix::put ()
329			{
330			chmod (name, RESTORE_TTY_MODE);
331			chown (name, 0, ttyconf.gid);
332	root	1.1
333	root	1.2	close_tty ();
334	root	1.1
335	root	1.2	if (pty >= 0)
336			close (pty);
337	root	1.1
338			free (name);
339
340			pty = tty = -1;
341			name = 0;
342			}
343
344			bool
345	root	1.2	rxvt_ptytty_unix::get ()
346	root	1.1	{
347			/* get master (pty) */
348			if ((pty = get_pty (&tty, &name)) < 0)
349			return false;
350
351			fcntl (pty, F_SETFL, O_NONBLOCK);
352
353			/* get slave (tty) */
354			if (tty < 0)
355			{
356			#ifndef NO_SETOWNER_TTYDEV
357	root	1.2	chown (name, getuid (), ttyconf.gid); /* fail silently */
358			chmod (name, ttyconf.mode);
359			# ifdef HAVE_REVOKE
360			revoke (name);
361			# endif
362	root	1.1	#endif
363
364			if ((tty = get_tty (name)) < 0)
365			{
366			put ();
367			return false;
368			}
369			}
370
371			return true;
372			}
373
374	root	1.2	#if PTYTTY_HELPER
375
376			static int sock_fd;
377			static int pid;
378
379			struct command
380			{
381			enum { get, login, destroy } type;
382
383			rxvt_ptytty *id;
384
385			bool login_shell;
386			int cmd_pid;
387			char hostname[512]; // arbitrary, but should be plenty
388			};
389
390			struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
391			{
392			rxvt_ptytty *id;
393
394			~rxvt_ptytty_proxy ();
395
396			bool get ();
397			void login (int cmd_pid, bool login_shell, const char *hostname);
398			};
399
400			bool
401			rxvt_ptytty_proxy::get ()
402			{
403			command cmd;
404
405			cmd.type = command::get;
406
407			write (sock_fd, &cmd, sizeof (cmd));
408
409			if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
410			rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");
411
412			if (!id)
413			return false;
414
415			if ((pty = rxvt_recv_fd (sock_fd)) < 0
416			\|\| (tty = rxvt_recv_fd (sock_fd)) < 0)
417			rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");
418
419			return true;
420			}
421
422	root	1.1	void
423	root	1.2	rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
424			{
425			command cmd;
426
427			cmd.type = command::login;
428			cmd.id = id;
429			cmd.cmd_pid = cmd_pid;
430			cmd.login_shell = login_shell;
431			strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));
432
433			write (sock_fd, &cmd, sizeof (cmd));
434			}
435
436			rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
437			{
438			command cmd;
439
440			cmd.type = command::destroy;
441			cmd.id = id;
442
443			write (sock_fd, &cmd, sizeof (cmd));
444			}
445
446			static
447			void serve ()
448	root	1.1	{
449	root	1.2	command cmd;
450			vector<rxvt_ptytty *> ptys;
451
452			while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
453	root	1.1	{
454	root	1.2	if (cmd.type == command::get)
455			{
456			// -> id ptyfd ttyfd
457			cmd.id = new rxvt_ptytty_unix;
458	root	1.1
459	root	1.2	if (cmd.id->get ())
460			{
461			write (sock_fd, &cmd.id, sizeof (cmd.id));
462			ptys.push_back (cmd.id);
463	root	1.1
464	root	1.2	rxvt_send_fd (sock_fd, cmd.id->pty);
465			rxvt_send_fd (sock_fd, cmd.id->tty);
466			}
467	root	1.1	else
468	root	1.2	{
469			delete cmd.id;
470			cmd.id = 0;
471			write (sock_fd, &cmd.id, sizeof (cmd.id));
472			}
473			}
474			else if (cmd.type == command::login)
475			{
476			#if UTMP_SUPPORT
477			if (find (ptys.begin (), ptys.end (), cmd.id))
478			{
479			cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
480			cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
481			}
482			#endif
483			}
484			else if (cmd.type == command::destroy)
485			{
486			rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);
487	root	1.1
488	root	1.2	if (pty)
489	root	1.1	{
490	root	1.2	delete *pty;
491			ptys.erase (pty);
492	root	1.1	}
493			}
494	root	1.2	else
495			break;
496	root	1.1	}
497	root	1.2
498			// destroy all ptys
499			for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
500			delete *i;
501			}
502
503			void rxvt_ptytty_server ()
504			{
505			int sv[2];
506
507			if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
508			rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");
509
510			pid = fork ();
511
512			if (pid < 0)
513			rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");
514
515			if (pid)
516			{
517			// client, urxvt
518			sock_fd = sv[0];
519			close (sv[1]);
520			fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
521			}
522			else
523			{
524			// server, pty-helper
525			sock_fd = sv[1];
526
527			for (int fd = 0; fd < 1023; fd++)
528			if (fd != sock_fd)
529			close (fd);
530
531			serve ();
532			_exit (EXIT_SUCCESS);
533			}
534			}
535
536			#endif
537
538			// a "factory" g
539			rxvt_ptytty *
540			rxvt_new_ptytty ()
541			{
542			#if PTYTTY_HELPER
543			if (pid > 0)
544			// use helper process
545			return new rxvt_ptytty_proxy;
546			else
547	root	1.1	#endif
548	root	1.2	return new rxvt_ptytty_unix;
549	root	1.1	}
550
551			/----------------------- end-of-file (C source) -----------------------/
552