rxvt-unicode/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 "rxvt.h"

#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(PTYS_ARE_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

#include <cstdio>
#include <grp.h>

#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
 */
static int
get_pty (int *fd_tty, char **ttydev)
{
  int pfd;

#ifdef PTYS_ARE_OPENPTY
  char tty_name[sizeof "/dev/pts/????\0"];

  int res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);

  if (res != -1)
    {
      *ttydev = strdup (tty_name);
      return pfd;
    }
#endif

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

#if defined(HAVE_GRANTPT) && defined(HAVE_UNLOCKPT)
# if defined(PTYS_ARE_GETPT) || defined(PTYS_ARE_POSIX) || defined(PTYS_ARE_PTMX)

  {
#  ifdef PTYS_ARE_GETPT
    pfd = getpt();
#  else
#  ifdef PTYS_ARE_POSIX
    pfd = posix_openpt (O_RDWR);
#  else
    pfd = open ("/dev/ptmx", O_RDWR | O_NOCTTY, 0);
#  endif
#  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);
      }
  }
# endif
#endif

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

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

#ifdef PTYS_ARE_NUMERIC
  {
    int idx;
    char *c1, *c2;
    char pty_name[] = "/dev/ptyp???";
    char tty_name[] = "/dev/ttyp???";

    c1 = &(pty_name[sizeof (pty_name) - 4]);
    c2 = &(tty_name[sizeof (tty_name) - 4]);
    for (idx = 0; idx < 256; idx++)
      {
        sprintf (c1, "%d", idx);
        sprintf (c2, "%d", idx);
        if (access (tty_name, F_OK) < 0)
          {
            idx = 256;
            break;
          }

        if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) >= 0)
          {
            if (access (tty_name, R_OK | W_OK) == 0)
              {
                *ttydev = strdup (tty_name);
                return pfd;
              }

            close (pfd);
          }
      }
  }
#endif

#ifdef PTYS_ARE_SEARCHED
  {
    const char *c1, *c2;
    char pty_name[] = "/dev/pty??";
    char tty_name[] = "/dev/tty??";

# ifndef PTYCHAR1
#  define PTYCHAR1      "pqrstuvwxyz"
# endif
# ifndef PTYCHAR2
#  define PTYCHAR2      "0123456789abcdef"
# endif

    for (c1 = PTYCHAR1; *c1; c1++)
      {
        pty_name[ (sizeof (pty_name) - 3)] =
          tty_name[ (sizeof (pty_name) - 3)] = *c1;
        for (c2 = PTYCHAR2; *c2; c2++)
          {
            pty_name[ (sizeof (pty_name) - 2)] =
              tty_name[ (sizeof (pty_name) - 2)] = *c2;
            if ((pfd = open (pty_name, O_RDWR | O_NOCTTY, 0)) >= 0)
              {
                if (access (tty_name, R_OK | W_OK) == 0)
                  {
                    *ttydev = strdup (tty_name);
                    return pfd;
                  }

                close (pfd);
              }
          }
      }
  }
#endif

  return -1;
}

/*----------------------------------------------------------------------*/
/*
 * 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)
{
  int fd;

  /* ---------------------------------------- */
  setsid ();

  /* ---------------------------------------- */
# if defined(PTYS_ARE_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
  /* ---------------------------------------- */
  fd = ioctl (fd_tty, TIOCSCTTY, NULL);
  /* ---------------------------------------- */
  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
}

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

#ifndef NO_SETOWNER_TTYDEV
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 = getgid ();
        }
    }
} ttyconf;

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

void
rxvt_ptytty_unix::privileges (rxvt_privaction action)
{
  if (!name || !*name)
    return;

  if (action == SAVE)
    {
# ifndef RESET_TTY_TO_COMMON_DEFAULTS
      /* store original tty status for restoration rxvt_clean_exit () -- rgg 04/12/95 */
      if (lstat (name, &savestat) < 0)       /* you lose out */
        ;
      else
# endif
        {
          saved = true;
          chown (name, getuid (), ttyconf.gid);      /* fail silently */
          chmod (name, ttyconf.mode);
# ifdef HAVE_REVOKE
          revoke (name);
# endif
        }
    }
  else
    {                    /* action == RESTORE */
# ifndef RESET_TTY_TO_COMMON_DEFAULTS
      if (saved)
        {
          chmod (name, savestat.st_mode);
          chown (name, savestat.st_uid, savestat.st_gid);
        }
# else
      chmod (name, (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH));
      chown (name, 0, 0);
# endif

    }
}
#endif

rxvt_ptytty_unix::rxvt_ptytty_unix ()
{
  pty = tty = -1;
  name = 0;
#ifndef NO_SETOWNER_TTYDEV
  saved = false;
#endif
#if UTMP_SUPPORT
  cmd_pid = 0;
#endif
}

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

void
rxvt_ptytty_unix::put ()
{
#ifndef NO_SETOWNER_TTYDEV
  privileges (RESTORE);
#endif

  if (pty >= 0) close (pty);
  close_tty ();
  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
      privileges (SAVE);
#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
    {
      setgid (getegid ());
      setuid (geteuid ());

      // server, pty-helper
      sock_fd = sv[1];

      for (int fd = 0; fd < 1023; fd++)
        if (fd != sock_fd && fd != 1)
          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:	1.43
Committed:	Tue Jan 17 16:50:42 2006 UTC (18 years, 4 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.42:	+4 -0 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	/---------------------------------C----------------------------------
2	pcg	1.11	* File: ptytty.C
3	pcg	1.1	----------------------------------------------------------------------
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	1.30	* Copyright (c) 2004-2006 Marc Lehmann <pcg@goof.com>
8	pcg	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	root	1.16	#include "rxvt.h"
26	pcg	1.1
27	root	1.40	#include <cstdlib>
28			#include <cstring>
29
30			#include <sys/types.h>
31			#include <sys/socket.h>
32			#include <unistd.h>
33			#include <fcntl.h>
34	root	1.31
35	pcg	1.1	#ifdef HAVE_SYS_IOCTL_H
36			# include <sys/ioctl.h>
37			#endif
38	root	1.12	#if defined(PTYS_ARE_PTMX) && defined(HAVE_SYS_STROPTS_H)
39	pcg	1.1	# include <sys/stropts.h> /* for I_PUSH */
40			#endif
41	pcg	1.10	#ifdef HAVE_ISASTREAM
42			# include <stropts.h>
43			#endif
44	root	1.31	#if defined(HAVE_PTY_H)
45	root	1.22	# include <pty.h>
46	root	1.31	#elif defined(HAVE_LIBUTIL_H)
47	root	1.16	# include <libutil.h>
48	root	1.31	#elif defined(HAVE_UTIL_H)
49	root	1.17	# include <util.h>
50	pcg	1.1	#endif
51
52	root	1.16	#include <cstdio>
53			#include <grp.h>
54
55	root	1.40	#include "rxvtutil.h"
56			#include "fdpass.h"
57	root	1.39	#include "ptytty.h"
58
59	root	1.36	/////////////////////////////////////////////////////////////////////////////
60
61	pcg	1.1	/* ------------------------------------------------------------------------- *
62			* GET PSEUDO TELETYPE - MASTER AND SLAVE *
63			* ------------------------------------------------------------------------- */
64			/*
65			* Returns pty file descriptor, or -1 on failure
66			* If successful, ttydev is set to the name of the slave device.
67			* fd_tty _may_ also be set to an open fd to the slave device
68			*/
69	root	1.16	static int
70			get_pty (int fd_tty, char *ttydev)
71	pcg	1.1	{
72	pcg	1.4	int pfd;
73	pcg	1.1
74			#ifdef PTYS_ARE_OPENPTY
75	root	1.26	char tty_name[sizeof "/dev/pts/????\0"];
76	pcg	1.4
77	root	1.27	int res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
78
79			if (res != -1)
80	pcg	1.4	{
81	pcg	1.6	*ttydev = strdup (tty_name);
82	pcg	1.4	return pfd;
83	pcg	1.1	}
84			#endif
85
86			#ifdef PTYS_ARE__GETPTY
87	pcg	1.6	*ttydev = _getpty (&pfd, O_RDWR \| O_NONBLOCK \| O_NOCTTY, 0622, 0);
88	pcg	1.4	if (*ttydev != NULL)
89			return pfd;
90	pcg	1.1	#endif
91
92			#if defined(HAVE_GRANTPT) && defined(HAVE_UNLOCKPT)
93	ayin	1.34	# if defined(PTYS_ARE_GETPT) \|\| defined(PTYS_ARE_POSIX) \|\| defined(PTYS_ARE_PTMX)
94	pcg	1.4
95			{
96	ayin	1.34	# ifdef PTYS_ARE_GETPT
97			pfd = getpt();
98			# else
99	root	1.33	# ifdef PTYS_ARE_POSIX
100			pfd = posix_openpt (O_RDWR);
101	pcg	1.1	# else
102	pcg	1.6	pfd = open ("/dev/ptmx", O_RDWR \| O_NOCTTY, 0);
103	pcg	1.1	# endif
104	ayin	1.34	# endif
105	pcg	1.4
106			if (pfd >= 0)
107			{
108	pcg	1.6	if (grantpt (pfd) == 0 /* change slave permissions */
109			&& unlockpt (pfd) == 0)
110	pcg	1.4	{ /* slave now unlocked */
111	root	1.16	ttydev = strdup (ptsname (pfd)); / get slave's name */
112	pcg	1.4	return pfd;
113			}
114	pcg	1.6	close (pfd);
115	pcg	1.4	}
116			}
117	pcg	1.1	# endif
118			#endif
119
120			#ifdef PTYS_ARE_PTC
121	pcg	1.6	if ((pfd = open ("/dev/ptc", O_RDWR \| O_NOCTTY, 0)) >= 0)
122	pcg	1.4	{
123	root	1.16	*ttydev = strdup (ttyname (pfd));
124	pcg	1.4	return pfd;
125	pcg	1.1	}
126			#endif
127
128			#ifdef PTYS_ARE_CLONE
129	pcg	1.6	if ((pfd = open ("/dev/ptym/clone", O_RDWR \| O_NOCTTY, 0)) >= 0)
130	pcg	1.4	{
131	root	1.16	*ttydev = strdup (ptsname (pfd));
132	pcg	1.4	return pfd;
133	pcg	1.1	}
134			#endif
135
136			#ifdef PTYS_ARE_NUMERIC
137	pcg	1.4	{
138	root	1.16	int idx;
139			char c1, c2;
140			char pty_name[] = "/dev/ptyp???";
141			char tty_name[] = "/dev/ttyp???";
142	pcg	1.4
143	root	1.16	c1 = &(pty_name[sizeof (pty_name) - 4]);
144			c2 = &(tty_name[sizeof (tty_name) - 4]);
145	pcg	1.4	for (idx = 0; idx < 256; idx++)
146			{
147	pcg	1.6	sprintf (c1, "%d", idx);
148			sprintf (c2, "%d", idx);
149			if (access (tty_name, F_OK) < 0)
150	pcg	1.4	{
151			idx = 256;
152			break;
153			}
154	root	1.16
155	pcg	1.6	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
156	pcg	1.4	{
157	pcg	1.6	if (access (tty_name, R_OK \| W_OK) == 0)
158	pcg	1.4	{
159	pcg	1.6	*ttydev = strdup (tty_name);
160	pcg	1.4	return pfd;
161			}
162	root	1.16
163	pcg	1.6	close (pfd);
164	pcg	1.4	}
165			}
166			}
167	pcg	1.1	#endif
168	root	1.16
169	pcg	1.1	#ifdef PTYS_ARE_SEARCHED
170	pcg	1.4	{
171	root	1.16	const char c1, c2;
172			char pty_name[] = "/dev/pty??";
173			char tty_name[] = "/dev/tty??";
174	pcg	1.1
175			# ifndef PTYCHAR1
176			# define PTYCHAR1 "pqrstuvwxyz"
177			# endif
178			# ifndef PTYCHAR2
179			# define PTYCHAR2 "0123456789abcdef"
180			# endif
181	pcg	1.4
182			for (c1 = PTYCHAR1; *c1; c1++)
183			{
184	pcg	1.6	pty_name[ (sizeof (pty_name) - 3)] =
185			tty_name[ (sizeof (pty_name) - 3)] = *c1;
186	pcg	1.4	for (c2 = PTYCHAR2; *c2; c2++)
187			{
188	pcg	1.6	pty_name[ (sizeof (pty_name) - 2)] =
189			tty_name[ (sizeof (pty_name) - 2)] = *c2;
190			if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
191	pcg	1.4	{
192	pcg	1.6	if (access (tty_name, R_OK \| W_OK) == 0)
193	pcg	1.4	{
194	pcg	1.6	*ttydev = strdup (tty_name);
195	pcg	1.4	return pfd;
196			}
197	root	1.16
198	pcg	1.6	close (pfd);
199	pcg	1.4	}
200			}
201			}
202			}
203	pcg	1.1	#endif
204	root	1.16
205	pcg	1.4	return -1;
206	pcg	1.1	}
207
208			/----------------------------------------------------------------------/
209			/*
210			* Returns tty file descriptor, or -1 on failure
211			*/
212	root	1.16	static int
213			get_tty (char *ttydev)
214	pcg	1.1	{
215	pcg	1.4	return open (ttydev, O_RDWR \| O_NOCTTY, 0);
216	pcg	1.1	}
217
218			/----------------------------------------------------------------------/
219			/*
220			* Make our tty a controlling tty so that /dev/tty points to us
221			*/
222	root	1.16	static int
223	root	1.36	control_tty (int fd_tty)
224	pcg	1.1	{
225	pcg	1.4	int fd;
226	pcg	1.1
227	pcg	1.4	/* ---------------------------------------- */
228			setsid ();
229	root	1.16
230	pcg	1.4	/* ---------------------------------------- */
231	root	1.36	# if defined(PTYS_ARE_PTMX) && defined(I_PUSH)
232	pcg	1.4	/*
233			* Push STREAMS modules:
234			* ptem: pseudo-terminal hardware emulation module.
235			* ldterm: standard terminal line discipline.
236			* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
237			*
238	pcg	1.6	* After we push the STREAMS modules, the first open () on the slave side
239	pcg	1.4	* (i.e. the next section between the dashes giving us "tty opened OK")
240			* should make the "ptem" (or "ldterm" depending upon either which OS
241			* version or which set of manual pages you have) module give us a
242	pcg	1.6	* controlling terminal. We must already have close ()d the master side
243	pcg	1.4	* fd in this child process before we push STREAMS modules on because the
244	pcg	1.6	* documentation is really unclear about whether it is any close () on
245			* the master side or the last close () - i.e. a proper STREAMS dismantling
246			* close () - on the master side which causes a hang up to be sent
247	pcg	1.4	* through - Geoff Wing
248			*/
249	root	1.36	# ifdef HAVE_ISASTREAM
250	pcg	1.4	if (isastream (fd_tty) == 1)
251	root	1.36	# endif
252	pcg	1.1	{
253	pcg	1.4	ioctl (fd_tty, I_PUSH, "ptem");
254			ioctl (fd_tty, I_PUSH, "ldterm");
255			ioctl (fd_tty, I_PUSH, "ttcompat");
256	pcg	1.1	}
257	root	1.36	# endif
258	pcg	1.4	/* ---------------------------------------- */
259			fd = ioctl (fd_tty, TIOCSCTTY, NULL);
260			/* ---------------------------------------- */
261			fd = open ("/dev/tty", O_WRONLY);
262			if (fd < 0)
263			return -1; /* fatal */
264			close (fd);
265			/* ---------------------------------------- */
266
267			return 0;
268	pcg	1.1	}
269	root	1.16
270	root	1.36	void
271			rxvt_ptytty::close_tty ()
272			{
273			if (tty < 0)
274			return;
275
276			close (tty);
277			tty = -1;
278			}
279
280			bool
281			rxvt_ptytty::make_controlling_tty ()
282			{
283			return control_tty (tty) >= 0;
284			}
285
286			void
287			rxvt_ptytty::set_utf8_mode (bool on)
288			{
289			#ifdef IUTF8
290			if (pty < 0)
291			return;
292
293			struct termios tio;
294
295			if (tcgetattr (pty, &tio) != -1)
296			{
297			tcflag_t new_cflag = tio.c_iflag;
298
299			if (on)
300			new_cflag \|= IUTF8;
301			else
302			new_cflag &= ~IUTF8;
303
304			if (new_cflag != tio.c_iflag)
305			{
306			tio.c_iflag = new_cflag;
307			tcsetattr (pty, TCSANOW, &tio);
308			}
309			}
310			#endif
311			}
312
313			/////////////////////////////////////////////////////////////////////////////
314
315	root	1.16	#ifndef NO_SETOWNER_TTYDEV
316			static struct ttyconf {
317			gid_t gid;
318			mode_t mode;
319
320			ttyconf ()
321			{
322			#ifdef TTY_GID_SUPPORT
323			struct group *gr = getgrnam ("tty");
324
325			if (gr)
326			{ /* change group ownership of tty to "tty" */
327			mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
328			gid = gr->gr_gid;
329			}
330			else
331			#endif /* TTY_GID_SUPPORT */
332			{
333			mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
334			gid = getgid ();
335			}
336			}
337			} ttyconf;
338
339	root	1.36	/////////////////////////////////////////////////////////////////////////////
340
341	root	1.16	void
342	root	1.36	rxvt_ptytty_unix::privileges (rxvt_privaction action)
343	root	1.16	{
344	root	1.26	if (!name \|\| !*name)
345	root	1.23	return;
346
347	root	1.16	if (action == SAVE)
348			{
349			# ifndef RESET_TTY_TO_COMMON_DEFAULTS
350			/* store original tty status for restoration rxvt_clean_exit () -- rgg 04/12/95 */
351			if (lstat (name, &savestat) < 0) /* you lose out */
352	root	1.26	;
353	root	1.16	else
354			# endif
355			{
356	root	1.26	saved = true;
357	root	1.16	chown (name, getuid (), ttyconf.gid); /* fail silently */
358			chmod (name, ttyconf.mode);
359			# ifdef HAVE_REVOKE
360			revoke (name);
361			# endif
362			}
363			}
364			else
365			{ /* action == RESTORE */
366			# ifndef RESET_TTY_TO_COMMON_DEFAULTS
367	root	1.26	if (saved)
368			{
369			chmod (name, savestat.st_mode);
370			chown (name, savestat.st_uid, savestat.st_gid);
371			}
372	root	1.16	# else
373			chmod (name, (S_IRUSR \| S_IWUSR \| S_IRGRP \| S_IWGRP \| S_IROTH \| S_IWOTH));
374			chown (name, 0, 0);
375			# endif
376
377			}
378			}
379			#endif
380
381	root	1.36	rxvt_ptytty_unix::rxvt_ptytty_unix ()
382	root	1.16	{
383			pty = tty = -1;
384			name = 0;
385	root	1.26	#ifndef NO_SETOWNER_TTYDEV
386			saved = false;
387			#endif
388	root	1.35	#if UTMP_SUPPORT
389			cmd_pid = 0;
390			#endif
391	root	1.16	}
392
393	root	1.36	rxvt_ptytty_unix::~rxvt_ptytty_unix ()
394	root	1.16	{
395	root	1.43	#if UTMP_SUPPORT
396	root	1.35	logout ();
397	root	1.43	#endif
398	root	1.16	put ();
399			}
400
401			void
402	root	1.36	rxvt_ptytty_unix::put ()
403	root	1.16	{
404			#ifndef NO_SETOWNER_TTYDEV
405	root	1.28	privileges (RESTORE);
406	root	1.16	#endif
407
408			if (pty >= 0) close (pty);
409			close_tty ();
410			free (name);
411
412			pty = tty = -1;
413			name = 0;
414			}
415
416			bool
417	root	1.36	rxvt_ptytty_unix::get ()
418	root	1.16	{
419			/* get master (pty) */
420			if ((pty = get_pty (&tty, &name)) < 0)
421			return false;
422
423			fcntl (pty, F_SETFL, O_NONBLOCK);
424
425			/* get slave (tty) */
426			if (tty < 0)
427			{
428			#ifndef NO_SETOWNER_TTYDEV
429			privileges (SAVE);
430			#endif
431
432			if ((tty = get_tty (name)) < 0)
433			{
434			put ();
435			return false;
436			}
437			}
438
439			return true;
440			}
441
442	root	1.40	#if PTYTTY_HELPER
443
444			static int sock_fd;
445			static int pid;
446
447			struct command
448			{
449			enum { get, login, destroy } type;
450
451			rxvt_ptytty *id;
452
453			bool login_shell;
454			int cmd_pid;
455			char hostname[512]; // arbitrary, but should be plenty
456			};
457
458			struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
459			{
460			rxvt_ptytty *id;
461
462			~rxvt_ptytty_proxy ();
463
464			bool get ();
465			void login (int cmd_pid, bool login_shell, const char *hostname);
466			};
467
468			bool
469			rxvt_ptytty_proxy::get ()
470			{
471			command cmd;
472
473			cmd.type = command::get;
474
475			write (sock_fd, &cmd, sizeof (cmd));
476
477			if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
478			rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");
479
480			if (!id)
481			return false;
482
483			if ((pty = rxvt_recv_fd (sock_fd)) < 0
484			\|\| (tty = rxvt_recv_fd (sock_fd)) < 0)
485			rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");
486
487			return true;
488			}
489
490			void
491			rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
492			{
493			command cmd;
494
495			cmd.type = command::login;
496			cmd.id = id;
497			cmd.cmd_pid = cmd_pid;
498			cmd.login_shell = login_shell;
499			strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));
500
501			write (sock_fd, &cmd, sizeof (cmd));
502			}
503
504			rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
505			{
506			command cmd;
507
508			cmd.type = command::destroy;
509			cmd.id = id;
510
511			write (sock_fd, &cmd, sizeof (cmd));
512			}
513
514			static
515			void serve ()
516			{
517			command cmd;
518			vector<rxvt_ptytty *> ptys;
519
520			while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
521			{
522			if (cmd.type == command::get)
523			{
524			// -> id ptyfd ttyfd
525			cmd.id = new rxvt_ptytty_unix;
526
527			if (cmd.id->get ())
528			{
529			write (sock_fd, &cmd.id, sizeof (cmd.id));
530			ptys.push_back (cmd.id);
531
532			rxvt_send_fd (sock_fd, cmd.id->pty);
533			rxvt_send_fd (sock_fd, cmd.id->tty);
534			}
535			else
536			{
537			delete cmd.id;
538			cmd.id = 0;
539			write (sock_fd, &cmd.id, sizeof (cmd.id));
540			}
541			}
542			else if (cmd.type == command::login)
543			{
544	root	1.43	#if UTMP_SUPPORT
545	root	1.40	if (find (ptys.begin (), ptys.end (), cmd.id))
546			{
547			cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
548			cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
549			}
550	root	1.43	#endif
551	root	1.40	}
552			else if (cmd.type == command::destroy)
553			{
554			rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);
555
556	root	1.42	if (pty)
557	root	1.40	{
558	root	1.42	delete *pty;
559	root	1.40	ptys.erase (pty);
560			}
561			}
562			else
563			break;
564			}
565
566			// destroy all ptys
567			for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
568			delete *i;
569			}
570
571			void rxvt_ptytty_server ()
572			{
573			int sv[2];
574
575			if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
576			rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");
577
578			pid = fork ();
579
580			if (pid < 0)
581			rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");
582
583			if (pid)
584			{
585			// client, urxvt
586			sock_fd = sv[0];
587			close (sv[1]);
588			fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
589			}
590			else
591			{
592	root	1.41	setgid (getegid ());
593			setuid (geteuid ());
594
595	root	1.40	// server, pty-helper
596			sock_fd = sv[1];
597
598	root	1.41	for (int fd = 0; fd < 1023; fd++)
599	root	1.42	if (fd != sock_fd && fd != 1)
600	root	1.41	close (fd);
601	root	1.40
602			serve ();
603			_exit (EXIT_SUCCESS);
604			}
605			}
606			#endif
607
608	root	1.39	// a "factory" g
609	root	1.40	rxvt_ptytty *
610			rxvt_new_ptytty ()
611	root	1.39	{
612	root	1.40	#if PTYTTY_HELPER
613			if (pid > 0)
614	root	1.41	// use helper process
615			return new rxvt_ptytty_proxy;
616	root	1.40	else
617			#endif
618			return new rxvt_ptytty_unix;
619	root	1.39	}
620
621	pcg	1.1	/----------------------- end-of-file (C source) -----------------------/
622	root	1.16