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 inline int
get_pty_streams (int *fd_tty, char **ttydev)
{
#ifdef NO_SETOWNER_TTYDEV
  int pfd;

# 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
  return -1;
}

static inline int
get_pty_openpty (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_OPENPTY
  int pfd;
  int res;
  char tty_name[sizeof "/dev/pts/????\0"];
  
  res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
  if (res != -1)
    {
      *ttydev = strdup (tty_name);
      return pfd;
    }
#endif
  return -1;
}

static inline int
get_pty__getpty (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE__GETPTY
  int pfd;

  *ttydev = _getpty (&pfd, O_RDWR | O_NONBLOCK | O_NOCTTY, 0622, 0);
  if (*ttydev != NULL)
    return pfd;
#endif
  return -1;
}

static inline int
get_pty_ptc (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_PTC
  int pfd;

  if ((pfd = open ("/dev/ptc", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ttyname (pfd));
      return pfd;
    }
#endif
  return -1;
}

static inline int
get_pty_clone (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_CLONE
  int pfd;

  if ((pfd = open ("/dev/ptym/clone", O_RDWR | O_NOCTTY, 0)) >= 0)
    {
      *ttydev = strdup (ptsname (pfd));
      return pfd;
    }
#endif
  return -1;
}

static inline int
get_pty_numeric (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_NUMERIC
    int pfd;
    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
    return -1;
}

static inline int
get_pty_searched (int *fd_tty, char **ttydev)
{
#ifdef PTYS_ARE_SEARCHED
# ifndef PTYCHAR1
#  define PTYCHAR1      "pqrstuvwxyz"
# endif
# ifndef PTYCHAR2
#  define PTYCHAR2      "0123456789abcdef"
# endif
    int pfd;
    const char *c1, *c2;
    char pty_name[] = "/dev/pty??";
    char tty_name[] = "/dev/tty??";

    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;
}

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

  if ((pfd = get_pty_streams (fd_tty, ttydev)) != -1
      || (pfd = get_pty_openpty (fd_tty, ttydev)) != -1
      || (pfd = get_pty__getpty (fd_tty, ttydev)) != -1
      || (pfd = get_pty_ptc (fd_tty, ttydev)) != -1
      || (pfd = get_pty_clone (fd_tty, ttydev)) != -1
      || (pfd = get_pty_numeric (fd_tty, ttydev)) != -1
      || (pfd = get_pty_searched (fd_tty, ttydev)) != -1)
    return pfd;
  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:	1.44
Committed:	Tue Jan 17 17:59:31 2006 UTC (18 years, 4 months ago) by ayin
Content type:	text/plain
Branch:	MAIN
Changes since 1.43:	+84 -41 lines
Log Message:	get_pty refactoring.
#	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	ayin	1.44	static inline int
70			get_pty_streams (int fd_tty, char *ttydev)
71	pcg	1.1	{
72	ayin	1.44	#ifdef NO_SETOWNER_TTYDEV
73	pcg	1.4	int pfd;
74	pcg	1.1
75	ayin	1.44	# ifdef PTYS_ARE_GETPT
76			pfd = getpt();
77			# else
78			# ifdef PTYS_ARE_POSIX
79			pfd = posix_openpt (O_RDWR);
80			# else
81			pfd = open ("/dev/ptmx", O_RDWR \| O_NOCTTY, 0);
82			# endif
83			# endif
84			if (pfd >= 0)
85			{
86			if (grantpt (pfd) == 0 /* change slave permissions */
87			&& unlockpt (pfd) == 0)
88			{ /* slave now unlocked */
89			ttydev = strdup (ptsname (pfd)); / get slave's name */
90			return pfd;
91			}
92			close (pfd);
93			}
94			#endif
95			return -1;
96			}
97
98			static inline int
99			get_pty_openpty (int fd_tty, char *ttydev)
100			{
101	pcg	1.1	#ifdef PTYS_ARE_OPENPTY
102	ayin	1.44	int pfd;
103			int res;
104	root	1.26	char tty_name[sizeof "/dev/pts/????\0"];
105	ayin	1.44
106			res = openpty (&pfd, fd_tty, tty_name, NULL, NULL);
107	root	1.27	if (res != -1)
108	pcg	1.4	{
109	pcg	1.6	*ttydev = strdup (tty_name);
110	pcg	1.4	return pfd;
111	pcg	1.1	}
112			#endif
113	ayin	1.44	return -1;
114			}
115	pcg	1.1
116	ayin	1.44	static inline int
117			get_pty__getpty (int fd_tty, char *ttydev)
118			{
119	pcg	1.1	#ifdef PTYS_ARE__GETPTY
120	ayin	1.44	int pfd;
121
122	pcg	1.6	*ttydev = _getpty (&pfd, O_RDWR \| O_NONBLOCK \| O_NOCTTY, 0622, 0);
123	pcg	1.4	if (*ttydev != NULL)
124			return pfd;
125	pcg	1.1	#endif
126	ayin	1.44	return -1;
127			}
128	pcg	1.1
129	ayin	1.44	static inline int
130			get_pty_ptc (int fd_tty, char *ttydev)
131			{
132			#ifdef PTYS_ARE_PTC
133			int pfd;
134	pcg	1.4
135	pcg	1.6	if ((pfd = open ("/dev/ptc", O_RDWR \| O_NOCTTY, 0)) >= 0)
136	pcg	1.4	{
137	root	1.16	*ttydev = strdup (ttyname (pfd));
138	pcg	1.4	return pfd;
139	pcg	1.1	}
140			#endif
141	ayin	1.44	return -1;
142			}
143	pcg	1.1
144	ayin	1.44	static inline int
145			get_pty_clone (int fd_tty, char *ttydev)
146			{
147	pcg	1.1	#ifdef PTYS_ARE_CLONE
148	ayin	1.44	int pfd;
149
150	pcg	1.6	if ((pfd = open ("/dev/ptym/clone", O_RDWR \| O_NOCTTY, 0)) >= 0)
151	pcg	1.4	{
152	root	1.16	*ttydev = strdup (ptsname (pfd));
153	pcg	1.4	return pfd;
154	pcg	1.1	}
155			#endif
156	ayin	1.44	return -1;
157			}
158	pcg	1.1
159	ayin	1.44	static inline int
160			get_pty_numeric (int fd_tty, char *ttydev)
161			{
162	pcg	1.1	#ifdef PTYS_ARE_NUMERIC
163	ayin	1.44	int pfd;
164	root	1.16	int idx;
165			char c1, c2;
166			char pty_name[] = "/dev/ptyp???";
167			char tty_name[] = "/dev/ttyp???";
168	pcg	1.4
169	root	1.16	c1 = &(pty_name[sizeof (pty_name) - 4]);
170			c2 = &(tty_name[sizeof (tty_name) - 4]);
171	pcg	1.4	for (idx = 0; idx < 256; idx++)
172			{
173	pcg	1.6	sprintf (c1, "%d", idx);
174			sprintf (c2, "%d", idx);
175			if (access (tty_name, F_OK) < 0)
176	pcg	1.4	{
177			idx = 256;
178			break;
179			}
180	root	1.16
181	pcg	1.6	if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
182	pcg	1.4	{
183	pcg	1.6	if (access (tty_name, R_OK \| W_OK) == 0)
184	pcg	1.4	{
185	pcg	1.6	*ttydev = strdup (tty_name);
186	pcg	1.4	return pfd;
187			}
188	root	1.16
189	pcg	1.6	close (pfd);
190	pcg	1.4	}
191			}
192	pcg	1.1	#endif
193	ayin	1.44	return -1;
194			}
195	root	1.16
196	ayin	1.44	static inline int
197			get_pty_searched (int fd_tty, char *ttydev)
198			{
199	pcg	1.1	#ifdef PTYS_ARE_SEARCHED
200			# ifndef PTYCHAR1
201			# define PTYCHAR1 "pqrstuvwxyz"
202			# endif
203			# ifndef PTYCHAR2
204			# define PTYCHAR2 "0123456789abcdef"
205			# endif
206	ayin	1.44	int pfd;
207			const char c1, c2;
208			char pty_name[] = "/dev/pty??";
209			char tty_name[] = "/dev/tty??";
210	pcg	1.4
211			for (c1 = PTYCHAR1; *c1; c1++)
212			{
213	pcg	1.6	pty_name[ (sizeof (pty_name) - 3)] =
214			tty_name[ (sizeof (pty_name) - 3)] = *c1;
215	pcg	1.4	for (c2 = PTYCHAR2; *c2; c2++)
216			{
217	pcg	1.6	pty_name[ (sizeof (pty_name) - 2)] =
218			tty_name[ (sizeof (pty_name) - 2)] = *c2;
219			if ((pfd = open (pty_name, O_RDWR \| O_NOCTTY, 0)) >= 0)
220	pcg	1.4	{
221	pcg	1.6	if (access (tty_name, R_OK \| W_OK) == 0)
222	pcg	1.4	{
223	pcg	1.6	*ttydev = strdup (tty_name);
224	pcg	1.4	return pfd;
225			}
226	root	1.16
227	pcg	1.6	close (pfd);
228	pcg	1.4	}
229			}
230			}
231	pcg	1.1	#endif
232	ayin	1.44	return -1;
233			}
234	root	1.16
235	ayin	1.44	static int
236			get_pty (int fd_tty, char *ttydev)
237			{
238			int pfd;
239
240			if ((pfd = get_pty_streams (fd_tty, ttydev)) != -1
241			\|\| (pfd = get_pty_openpty (fd_tty, ttydev)) != -1
242			\|\| (pfd = get_pty__getpty (fd_tty, ttydev)) != -1
243			\|\| (pfd = get_pty_ptc (fd_tty, ttydev)) != -1
244			\|\| (pfd = get_pty_clone (fd_tty, ttydev)) != -1
245			\|\| (pfd = get_pty_numeric (fd_tty, ttydev)) != -1
246			\|\| (pfd = get_pty_searched (fd_tty, ttydev)) != -1)
247			return pfd;
248	pcg	1.4	return -1;
249	pcg	1.1	}
250
251			/----------------------------------------------------------------------/
252			/*
253			* Returns tty file descriptor, or -1 on failure
254			*/
255	root	1.16	static int
256			get_tty (char *ttydev)
257	pcg	1.1	{
258	pcg	1.4	return open (ttydev, O_RDWR \| O_NOCTTY, 0);
259	pcg	1.1	}
260
261			/----------------------------------------------------------------------/
262			/*
263			* Make our tty a controlling tty so that /dev/tty points to us
264			*/
265	root	1.16	static int
266	root	1.36	control_tty (int fd_tty)
267	pcg	1.1	{
268	pcg	1.4	int fd;
269	pcg	1.1
270	pcg	1.4	/* ---------------------------------------- */
271			setsid ();
272	root	1.16
273	pcg	1.4	/* ---------------------------------------- */
274	root	1.36	# if defined(PTYS_ARE_PTMX) && defined(I_PUSH)
275	pcg	1.4	/*
276			* Push STREAMS modules:
277			* ptem: pseudo-terminal hardware emulation module.
278			* ldterm: standard terminal line discipline.
279			* ttcompat: V7, 4BSD and XENIX STREAMS compatibility module.
280			*
281	pcg	1.6	* After we push the STREAMS modules, the first open () on the slave side
282	pcg	1.4	* (i.e. the next section between the dashes giving us "tty opened OK")
283			* should make the "ptem" (or "ldterm" depending upon either which OS
284			* version or which set of manual pages you have) module give us a
285	pcg	1.6	* controlling terminal. We must already have close ()d the master side
286	pcg	1.4	* fd in this child process before we push STREAMS modules on because the
287	pcg	1.6	* documentation is really unclear about whether it is any close () on
288			* the master side or the last close () - i.e. a proper STREAMS dismantling
289			* close () - on the master side which causes a hang up to be sent
290	pcg	1.4	* through - Geoff Wing
291			*/
292	root	1.36	# ifdef HAVE_ISASTREAM
293	pcg	1.4	if (isastream (fd_tty) == 1)
294	root	1.36	# endif
295	pcg	1.1	{
296	pcg	1.4	ioctl (fd_tty, I_PUSH, "ptem");
297			ioctl (fd_tty, I_PUSH, "ldterm");
298			ioctl (fd_tty, I_PUSH, "ttcompat");
299	pcg	1.1	}
300	root	1.36	# endif
301	pcg	1.4	/* ---------------------------------------- */
302			fd = ioctl (fd_tty, TIOCSCTTY, NULL);
303			/* ---------------------------------------- */
304			fd = open ("/dev/tty", O_WRONLY);
305			if (fd < 0)
306			return -1; /* fatal */
307			close (fd);
308			/* ---------------------------------------- */
309
310			return 0;
311	pcg	1.1	}
312	root	1.16
313	root	1.36	void
314			rxvt_ptytty::close_tty ()
315			{
316			if (tty < 0)
317			return;
318
319			close (tty);
320			tty = -1;
321			}
322
323			bool
324			rxvt_ptytty::make_controlling_tty ()
325			{
326			return control_tty (tty) >= 0;
327			}
328
329			void
330			rxvt_ptytty::set_utf8_mode (bool on)
331			{
332			#ifdef IUTF8
333			if (pty < 0)
334			return;
335
336			struct termios tio;
337
338			if (tcgetattr (pty, &tio) != -1)
339			{
340			tcflag_t new_cflag = tio.c_iflag;
341
342			if (on)
343			new_cflag \|= IUTF8;
344			else
345			new_cflag &= ~IUTF8;
346
347			if (new_cflag != tio.c_iflag)
348			{
349			tio.c_iflag = new_cflag;
350			tcsetattr (pty, TCSANOW, &tio);
351			}
352			}
353			#endif
354			}
355
356			/////////////////////////////////////////////////////////////////////////////
357
358	root	1.16	#ifndef NO_SETOWNER_TTYDEV
359			static struct ttyconf {
360			gid_t gid;
361			mode_t mode;
362
363			ttyconf ()
364			{
365			#ifdef TTY_GID_SUPPORT
366			struct group *gr = getgrnam ("tty");
367
368			if (gr)
369			{ /* change group ownership of tty to "tty" */
370			mode = S_IRUSR \| S_IWUSR \| S_IWGRP;
371			gid = gr->gr_gid;
372			}
373			else
374			#endif /* TTY_GID_SUPPORT */
375			{
376			mode = S_IRUSR \| S_IWUSR \| S_IWGRP \| S_IWOTH;
377			gid = getgid ();
378			}
379			}
380			} ttyconf;
381
382	root	1.36	/////////////////////////////////////////////////////////////////////////////
383
384	root	1.16	void
385	root	1.36	rxvt_ptytty_unix::privileges (rxvt_privaction action)
386	root	1.16	{
387	root	1.26	if (!name \|\| !*name)
388	root	1.23	return;
389
390	root	1.16	if (action == SAVE)
391			{
392			# ifndef RESET_TTY_TO_COMMON_DEFAULTS
393			/* store original tty status for restoration rxvt_clean_exit () -- rgg 04/12/95 */
394			if (lstat (name, &savestat) < 0) /* you lose out */
395	root	1.26	;
396	root	1.16	else
397			# endif
398			{
399	root	1.26	saved = true;
400	root	1.16	chown (name, getuid (), ttyconf.gid); /* fail silently */
401			chmod (name, ttyconf.mode);
402			# ifdef HAVE_REVOKE
403			revoke (name);
404			# endif
405			}
406			}
407			else
408			{ /* action == RESTORE */
409			# ifndef RESET_TTY_TO_COMMON_DEFAULTS
410	root	1.26	if (saved)
411			{
412			chmod (name, savestat.st_mode);
413			chown (name, savestat.st_uid, savestat.st_gid);
414			}
415	root	1.16	# else
416			chmod (name, (S_IRUSR \| S_IWUSR \| S_IRGRP \| S_IWGRP \| S_IROTH \| S_IWOTH));
417			chown (name, 0, 0);
418			# endif
419
420			}
421			}
422			#endif
423
424	root	1.36	rxvt_ptytty_unix::rxvt_ptytty_unix ()
425	root	1.16	{
426			pty = tty = -1;
427			name = 0;
428	root	1.26	#ifndef NO_SETOWNER_TTYDEV
429			saved = false;
430			#endif
431	root	1.35	#if UTMP_SUPPORT
432			cmd_pid = 0;
433			#endif
434	root	1.16	}
435
436	root	1.36	rxvt_ptytty_unix::~rxvt_ptytty_unix ()
437	root	1.16	{
438	root	1.43	#if UTMP_SUPPORT
439	root	1.35	logout ();
440	root	1.43	#endif
441	root	1.16	put ();
442			}
443
444			void
445	root	1.36	rxvt_ptytty_unix::put ()
446	root	1.16	{
447			#ifndef NO_SETOWNER_TTYDEV
448	root	1.28	privileges (RESTORE);
449	root	1.16	#endif
450
451			if (pty >= 0) close (pty);
452			close_tty ();
453			free (name);
454
455			pty = tty = -1;
456			name = 0;
457			}
458
459			bool
460	root	1.36	rxvt_ptytty_unix::get ()
461	root	1.16	{
462			/* get master (pty) */
463			if ((pty = get_pty (&tty, &name)) < 0)
464			return false;
465
466			fcntl (pty, F_SETFL, O_NONBLOCK);
467
468			/* get slave (tty) */
469			if (tty < 0)
470			{
471			#ifndef NO_SETOWNER_TTYDEV
472			privileges (SAVE);
473			#endif
474
475			if ((tty = get_tty (name)) < 0)
476			{
477			put ();
478			return false;
479			}
480			}
481
482			return true;
483			}
484
485	root	1.40	#if PTYTTY_HELPER
486
487			static int sock_fd;
488			static int pid;
489
490			struct command
491			{
492			enum { get, login, destroy } type;
493
494			rxvt_ptytty *id;
495
496			bool login_shell;
497			int cmd_pid;
498			char hostname[512]; // arbitrary, but should be plenty
499			};
500
501			struct rxvt_ptytty_proxy : zero_initialized, rxvt_ptytty
502			{
503			rxvt_ptytty *id;
504
505			~rxvt_ptytty_proxy ();
506
507			bool get ();
508			void login (int cmd_pid, bool login_shell, const char *hostname);
509			};
510
511			bool
512			rxvt_ptytty_proxy::get ()
513			{
514			command cmd;
515
516			cmd.type = command::get;
517
518			write (sock_fd, &cmd, sizeof (cmd));
519
520			if (read (sock_fd, &id, sizeof (id)) != sizeof (id))
521			rxvt_fatal ("protocol error while creating pty using helper process, aborting.\n");
522
523			if (!id)
524			return false;
525
526			if ((pty = rxvt_recv_fd (sock_fd)) < 0
527			\|\| (tty = rxvt_recv_fd (sock_fd)) < 0)
528			rxvt_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n");
529
530			return true;
531			}
532
533			void
534			rxvt_ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname)
535			{
536			command cmd;
537
538			cmd.type = command::login;
539			cmd.id = id;
540			cmd.cmd_pid = cmd_pid;
541			cmd.login_shell = login_shell;
542			strncpy (cmd.hostname, hostname, sizeof (cmd.hostname));
543
544			write (sock_fd, &cmd, sizeof (cmd));
545			}
546
547			rxvt_ptytty_proxy::~rxvt_ptytty_proxy ()
548			{
549			command cmd;
550
551			cmd.type = command::destroy;
552			cmd.id = id;
553
554			write (sock_fd, &cmd, sizeof (cmd));
555			}
556
557			static
558			void serve ()
559			{
560			command cmd;
561			vector<rxvt_ptytty *> ptys;
562
563			while (read (sock_fd, &cmd, sizeof (command)) == sizeof (command))
564			{
565			if (cmd.type == command::get)
566			{
567			// -> id ptyfd ttyfd
568			cmd.id = new rxvt_ptytty_unix;
569
570			if (cmd.id->get ())
571			{
572			write (sock_fd, &cmd.id, sizeof (cmd.id));
573			ptys.push_back (cmd.id);
574
575			rxvt_send_fd (sock_fd, cmd.id->pty);
576			rxvt_send_fd (sock_fd, cmd.id->tty);
577			}
578			else
579			{
580			delete cmd.id;
581			cmd.id = 0;
582			write (sock_fd, &cmd.id, sizeof (cmd.id));
583			}
584			}
585			else if (cmd.type == command::login)
586			{
587	root	1.43	#if UTMP_SUPPORT
588	root	1.40	if (find (ptys.begin (), ptys.end (), cmd.id))
589			{
590			cmd.hostname[sizeof (cmd.hostname) - 1] = 0;
591			cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname);
592			}
593	root	1.43	#endif
594	root	1.40	}
595			else if (cmd.type == command::destroy)
596			{
597			rxvt_ptytty **pty = find (ptys.begin (), ptys.end (), cmd.id);
598
599	root	1.42	if (pty)
600	root	1.40	{
601	root	1.42	delete *pty;
602	root	1.40	ptys.erase (pty);
603			}
604			}
605			else
606			break;
607			}
608
609			// destroy all ptys
610			for (rxvt_ptytty **i = ptys.end (); i-- > ptys.begin (); )
611			delete *i;
612			}
613
614			void rxvt_ptytty_server ()
615			{
616			int sv[2];
617
618			if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv))
619			rxvt_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n");
620
621			pid = fork ();
622
623			if (pid < 0)
624			rxvt_fatal ("could not create pty/sessiondb helper process, aborting.\n");
625
626			if (pid)
627			{
628			// client, urxvt
629			sock_fd = sv[0];
630			close (sv[1]);
631			fcntl (sock_fd, F_SETFD, FD_CLOEXEC);
632			}
633			else
634			{
635	root	1.41	setgid (getegid ());
636			setuid (geteuid ());
637
638	root	1.40	// server, pty-helper
639			sock_fd = sv[1];
640
641	root	1.41	for (int fd = 0; fd < 1023; fd++)
642	root	1.42	if (fd != sock_fd && fd != 1)
643	root	1.41	close (fd);
644	root	1.40
645			serve ();
646			_exit (EXIT_SUCCESS);
647			}
648			}
649			#endif
650
651	root	1.39	// a "factory" g
652	root	1.40	rxvt_ptytty *
653			rxvt_new_ptytty ()
654	root	1.39	{
655	root	1.40	#if PTYTTY_HELPER
656			if (pid > 0)
657	root	1.41	// use helper process
658			return new rxvt_ptytty_proxy;
659	root	1.40	else
660			#endif
661			return new rxvt_ptytty_unix;
662	root	1.39	}
663
664	pcg	1.1	/----------------------- end-of-file (C source) -----------------------/
665	root	1.16