NetBSD/gnu/libexec/uucp/common_sources/tli.c

/* tli.c
   Code to handle TLI connections.

   Copyright (C) 1992 Ian Lance Taylor

   This file is part of the Taylor UUCP package.

   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.

   The author of the program may be contacted at ian@airs.com or
   c/o Infinity Development Systems, P.O. Box 520, Waltham, MA 02254.
   */

#include "uucp.h"

#if USE_RCS_ID
const char tli_rcsid[] = "$Id: tli.c,v 1.1 1993/08/04 19:31:09 jtc Exp $";
#endif

#if HAVE_TLI

#include "sysdep.h"
#include "uudefs.h"
#include "uuconf.h"
#include "conn.h"
#include "system.h"

#include <errno.h>

#if HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif

#if HAVE_TIUSER_H
#include <tiuser.h>
#else
#if HAVE_XTI_H
#include <xti.h>
#else
#if HAVE_SYS_TLI_H
#include <sys/tli.h>
#endif
#endif
#endif

#if HAVE_STROPTS_H
#include <stropts.h>
#endif

#if HAVE_FCNTL_H
#include <fcntl.h>
#else
#if HAVE_SYS_FILE_H
#include <sys/file.h>
#endif
#endif

#ifndef O_RDONLY
#define O_RDONLY 0
#define O_WRONLY 1
#define O_RDWR 2
#endif

#ifndef FD_CLOEXEC
#define FD_CLOEXEC 1
#endif

/* The arguments to t_alloca have two different names.  I want the
   SVID ones, not the XPG3 ones.  */
#ifndef T_BIND
#define T_BIND T_BIND_STR
#endif
#ifndef T_CALL
#define T_CALL T_CALL_STR
#endif

/* Hopefully these externs will not cause any trouble.  This is how
   they are shown in the SVID.  */
extern int t_errno;
extern char *t_errlist[];
extern int t_nerr;

#ifndef t_alloc
extern pointer t_alloc ();
#endif

/* This code handles TLI connections.  It's Unix specific.  It's
   largely based on code from Unix Network Programming, by W. Richard
   Stevens.  */

/* Local functions.  */
static const char *ztlierror P((void));
static void utli_free P((struct sconnection *qconn));
static boolean ftli_push P((struct sconnection *qconn));
static boolean ftli_open P((struct sconnection *qconn, long ibaud,
			    boolean fwait));
static boolean ftli_close P((struct sconnection *qconn,
			     pointer puuconf,
			     struct uuconf_dialer *qdialer,
			     boolean fsuccess));
static boolean ftli_reset P((struct sconnection *qconn));
static boolean ftli_dial P((struct sconnection *qconn, pointer puuconf,
			    const struct uuconf_system *qsys,
			    const char *zphone,
			    struct uuconf_dialer *qdialer,
			    enum tdialerfound *ptdialer));

/* The command table for a TLI connection.  */
static const struct sconncmds stlicmds =
{
  utli_free,
  NULL, /* pflock */
  NULL, /* pfunlock */
  ftli_open,
  ftli_close,
  ftli_reset,
  ftli_dial,
  fsysdep_conn_read,
  fsysdep_conn_write,
  fsysdep_conn_io,
  NULL, /* pfbreak */
  NULL, /* pfset */
  NULL, /* pfcarrier */
  fsysdep_conn_chat,
  NULL /* pibaud */
};

/* Get a TLI error string.  */

static const char *
ztlierror ()
{
  if (t_errno == TSYSERR)
    return strerror (errno);
  if (t_errno < 0 || t_errno >= t_nerr)
    return "Unknown TLI error";
  return t_errlist[t_errno];
} 

/* Initialize a TLI connection.  */

boolean
fsysdep_tli_init (qconn)
     struct sconnection *qconn;
{
  struct ssysdep_conn *q;

  q = (struct ssysdep_conn *) xmalloc (sizeof (struct ssysdep_conn));
  q->o = -1;
  q->zdevice = NULL;
  q->iflags = -1;
  q->istdout_flags = -1;
  q->fterminal = FALSE;
  q->ftli = TRUE;
  q->ibaud = 0;

  qconn->psysdep = (pointer) q;
  qconn->qcmds = &stlicmds;
  return TRUE;
}

/* Free a TLI connection.  */

static void
utli_free (qconn)
     struct sconnection *qconn;
{
  xfree (qconn->psysdep);
}

/* Push all desired modules onto a TLI stream.  If the user requests a
   STREAMS connection without giving a list of modules, we just push
   tirdwr.  If the I_PUSH ioctl is not defined on this system, we just
   ignore any list of modules.  */

static boolean
ftli_push (qconn)
     struct sconnection *qconn;
{
#ifdef I_PUSH

  struct ssysdep_conn *qsysdep;

  qsysdep = (struct ssysdep_conn *) qconn->psysdep;

  if (qconn->qport->uuconf_u.uuconf_stli.uuconf_pzpush != NULL)
    {
      char **pz;

      for (pz = qconn->qport->uuconf_u.uuconf_stli.uuconf_pzpush;
	   *pz != NULL;
	   pz++)
	{
	  if (ioctl (qsysdep->o, I_PUSH, *pz) < 0)
	    {
	      ulog (LOG_ERROR, "ioctl (I_PUSH, %s): %s", *pz,
		    strerror (errno));
	      return FALSE;
	    }
	}
    }
  else if (qconn->qport->uuconf_u.uuconf_stli.uuconf_fstream)
    {
      if (ioctl (qsysdep->o, I_PUSH, "tirdwr") < 0)
	{
	  ulog (LOG_ERROR, "ioctl (I_PUSH, tirdwr): %s",
		strerror (errno));
	  return FALSE;
	}
    }

  /* If we have just put the connection into stream mode, we must turn
     off the TLI flag to avoid using TLI calls on it.  */
  if (qconn->qport->uuconf_u.uuconf_stli.uuconf_fstream)
    qsysdep->ftli = FALSE;

#endif /* defined (I_PUSH) */
  
  return TRUE;
}

/* Open a TLI connection.  If the fwait argument is TRUE, we are
   running as a server.  Otherwise we are just trying to reach another
   system.  */

static boolean
ftli_open (qconn, ibaud, fwait)
     struct sconnection *qconn;
     long ibaud;
     boolean fwait;
{
  struct ssysdep_conn *qsysdep;
  const char *zdevice;
  char *zfreedev;
  const char *zservaddr;
  char *zfreeaddr;
  struct t_bind *qtbind;
  struct t_call *qtcall;

  /* Unlike most other device types, we don't bother to call
     ulog_device here, because fconn_open calls it with the name of
     the port anyhow.  */

  qsysdep = (struct ssysdep_conn *) qconn->psysdep;

  zdevice = qconn->qport->uuconf_u.uuconf_stli.uuconf_zdevice;
  if (zdevice == NULL)
    zdevice = qconn->qport->uuconf_zname;

  zfreedev = NULL;
  if (*zdevice != '/')
    {
      zfreedev = zbufalc (sizeof "/dev/" + strlen (zdevice));
      sprintf (zfreedev, "/dev/%s", zdevice);
      zdevice = zfreedev;
    }

  qsysdep->o = t_open (zdevice, O_RDWR, (struct t_info *) NULL);
  if (qsysdep->o < 0)
    {
      ulog (LOG_ERROR, "t_open (%s): %s", zdevice, ztlierror ());
      ubuffree (zfreedev);
      return FALSE;
    }

  if (fcntl (qsysdep->o, F_SETFD,
	     fcntl (qsysdep->o, F_GETFD, 0) | FD_CLOEXEC) < 0)
    {
      ulog (LOG_ERROR, "fcntl (FD_CLOEXEC): %s", strerror (errno));
      ubuffree (zfreedev);
      (void) t_close (qsysdep->o);
      qsysdep->o = -1;
      return FALSE;
    }

  qsysdep->iflags = fcntl (qsysdep->o, F_GETFL, 0);
  if (qsysdep->iflags < 0)
    {
      ulog (LOG_ERROR, "fcntl: %s", strerror (errno));
      ubuffree (zfreedev);
      (void) t_close (qsysdep->o);
      qsysdep->o = -1;
      return FALSE;
    }

  /* If we aren't waiting for a connection, we can bind to any local
     address, and then we're finished.  */
  if (! fwait)
    {
      ubuffree (zfreedev);
      if (t_bind (qsysdep->o, (struct t_bind *) NULL,
		  (struct t_bind *) NULL) < 0)
	{
	  ulog (LOG_ERROR, "t_bind: %s", ztlierror ());
	  (void) t_close (qsysdep->o);
	  qsysdep->o = -1;
	  return FALSE;
	}
      return TRUE;
    }

  /* Run as a server and wait for a new connection.  The code in
     uucico.c has already detached us from our controlling terminal.
     From this point on if the server gets an error we exit; we only
     return if we have received a connection.  It would be more robust
     to respawn the server if it fails; someday.  */
  qtbind = (struct t_bind *) t_alloc (qsysdep->o, T_BIND, T_ALL);
  if (qtbind == NULL)
    ulog (LOG_FATAL, "t_alloc (T_BIND): %s", ztlierror ());

  zservaddr = qconn->qport->uuconf_u.uuconf_stli.uuconf_zservaddr;
  if (zservaddr == NULL)
    ulog (LOG_FATAL, "Can't run as TLI server; no server address");
      
  zfreeaddr = zbufcpy (zservaddr);
  qtbind->addr.len = cescape (zfreeaddr);
  if (qtbind->addr.len > qtbind->addr.maxlen)
    ulog (LOG_FATAL, "%s: TLI server address too long (max %d)",
	  zservaddr, qtbind->addr.maxlen);
  memcpy (qtbind->addr.buf, zfreeaddr, qtbind->addr.len);
  ubuffree (zfreeaddr);

  qtbind->qlen = 5;

  if (t_bind (qsysdep->o, qtbind, (struct t_bind *) NULL) < 0)
    ulog (LOG_FATAL, "t_bind (%s): %s", zservaddr, ztlierror ());

  (void) t_free ((pointer) qtbind, T_BIND);

  qtcall = (struct t_call *) t_alloc (qsysdep->o, T_CALL, T_ALL);
  if (qtcall == NULL)
    ulog (LOG_FATAL, "t_alloc (T_CALL): %s", ztlierror ());

  while (! FGOT_SIGNAL ())
    {
      int onew;
      pid_t ipid;

      DEBUG_MESSAGE0 (DEBUG_PORT,
		      "ftli_open: Waiting for connections");

      if (t_listen (qsysdep->o, qtcall) < 0)
	ulog (LOG_FATAL, "t_listen: %s", ztlierror ());

      onew = t_open (zdevice, O_RDWR, (struct t_info *) NULL);
      if (onew < 0)
	ulog (LOG_FATAL, "t_open (%s): %s", zdevice, ztlierror ());
	  
      if (fcntl (onew, F_SETFD,
		 fcntl (onew, F_GETFD, 0) | FD_CLOEXEC) < 0)
	ulog (LOG_FATAL, "fcntl (FD_CLOEXEC): %s", strerror (errno));

      if (t_bind (onew, (struct t_bind *) NULL, (struct t_bind *) NULL) < 0)
	ulog (LOG_FATAL, "t_bind: %s", ztlierror ());

      if (t_accept (qsysdep->o, onew, qtcall) < 0)
	{
	  /* We may have received a disconnect.  */
	  if (t_errno != TLOOK)
	    ulog (LOG_FATAL, "t_accept: %s", ztlierror ());
	  if (t_rcvdis (qsysdep->o, (struct t_discon *) NULL) < 0)
	    ulog (LOG_FATAL, "t_rcvdis: %s", ztlierror ());
	  (void) t_close (onew);
	  continue;
	}

      DEBUG_MESSAGE0 (DEBUG_PORT,
		      "ftli_open: Got connection; forking");

      ipid = ixsfork ();
      if (ipid < 0)
	ulog (LOG_FATAL, "fork: %s", strerror (errno));
      if (ipid == 0)
	{
	  ulog_close ();

	  (void) t_close (qsysdep->o);
	  qsysdep->o = onew;

	  /* Push any desired modules.  */
	  if (! ftli_push (qconn))
	    _exit (EXIT_FAILURE);

	  /* Now we fork and let our parent die, so that we become
	     a child of init.  This lets the main server code wait
	     for its child and then continue without accumulating
	     zombie children.  */
	  ipid = ixsfork ();
	  if (ipid < 0)
	    {
	      ulog (LOG_ERROR, "fork: %s", strerror (errno));
	      _exit (EXIT_FAILURE);
	    }
	      
	  if (ipid != 0)
	    _exit (EXIT_SUCCESS);

	  ulog_id (getpid ());

	  return TRUE;
	}

      (void) t_close (onew);

      /* Now wait for the child.  */
      (void) ixswait ((unsigned long) ipid, (const char *) NULL);
    }

  /* We got a signal.  */
  usysdep_exit (FALSE);

  /* Avoid compiler warnings.  */
  return FALSE;
}

/* Close the port.  */

/*ARGSUSED*/
static boolean
ftli_close (qconn, puuconf, qdialer, fsuccess)
     struct sconnection *qconn;
     pointer puuconf;
     struct uuconf_dialer *qdialer;
     boolean fsuccess;
{
  struct ssysdep_conn *qsysdep;
  boolean fret;

  qsysdep = (struct ssysdep_conn *) qconn->psysdep;

  fret = TRUE;
  if (qsysdep->o >= 0)
    {
      if (qsysdep->ftli)
	{
	  if (t_close (qsysdep->o) < 0)
	    {
	      ulog (LOG_ERROR, "t_close: %s", ztlierror ());
	      fret = FALSE;
	    }
	}
      else
	{
	  if (close (qsysdep->o) < 0)
	    {
	      ulog (LOG_ERROR, "close: %s", strerror (errno));
	      fret = FALSE;
	    }
	}

      qsysdep->o = -1;
    }

  return fret;
}

/* Reset the port.  This will be called by a child which was forked
   off in ftli_open, above.  We don't want uucico to continue looping
   and giving login prompts, so we pretend that we received a SIGINT
   signal.  This should probably be handled more cleanly.  The signal
   will not be recorded in the log file because we don't set
   afLog_signal[INDEXSIG_SIGINT].  */

/*ARGSUSED*/
static boolean
ftli_reset (qconn)
     struct sconnection *qconn;
{
  afSignal[INDEXSIG_SIGINT] = TRUE;
  return TRUE;
}

/* Dial out on a TLI port, so to speak: connect to a remote computer.  */

/*ARGSUSED*/
static boolean
ftli_dial (qconn, puuconf, qsys, zphone, qdialer, ptdialerfound)
     struct sconnection *qconn;
     pointer puuconf;
     const struct uuconf_system *qsys;
     const char *zphone;
     struct uuconf_dialer *qdialer;
     enum tdialerfound *ptdialerfound;
{
  struct ssysdep_conn *qsysdep;
  char **pzdialer;
  const char *zaddr;
  struct t_call *qtcall;
  char *zescape;

  qsysdep = (struct ssysdep_conn *) qconn->psysdep;

  *ptdialerfound = DIALERFOUND_FALSE;

  pzdialer = qconn->qport->uuconf_u.uuconf_stli.uuconf_pzdialer;
  if (*pzdialer == NULL)
    pzdialer = NULL;

  /* If the first dialer is "TLI" or "TLIS", we use the first token
     (pzdialer[1]) as the address to connect to.  */
  zaddr = zphone;
  if (pzdialer != NULL
      && (strcmp (pzdialer[0], "TLI") == 0
	  || strcmp (pzdialer[0], "TLIS") == 0))
    {
      if (pzdialer[1] == NULL)
	++pzdialer;
      else
	{
	  if (strcmp (pzdialer[1], "\\D") != 0
	      && strcmp (pzdialer[1], "\\T") != 0)
	    zaddr = pzdialer[1];
	  pzdialer += 2;
	}
    }
  
  if (zaddr == NULL)
    {
      ulog (LOG_ERROR, "No address for TLI connection");
      return FALSE;
    }

  qtcall = (struct t_call *) t_alloc (qsysdep->o, T_CALL, T_ADDR);
  if (qtcall == NULL)
    {
      ulog (LOG_ERROR, "t_alloc (T_CALL): %s", ztlierror ());
      return FALSE;
    }

  zescape = zbufcpy (zaddr);
  qtcall->addr.len = cescape (zescape);
  if (qtcall->addr.len > qtcall->addr.maxlen)
    {
      ulog (LOG_ERROR, "%s: TLI address too long (max %d)", zaddr,
	    qtcall->addr.maxlen);
      ubuffree (zescape);
      return FALSE;
    }
  memcpy (qtcall->addr.buf, zescape, qtcall->addr.len);
  ubuffree (zescape);

  if (t_connect (qsysdep->o, qtcall, (struct t_call *) NULL) < 0)
    {
      if (t_errno != TLOOK)
	ulog (LOG_ERROR, "t_connect: %s", ztlierror ());
      else
	{
	  if (t_rcvdis (qsysdep->o, (struct t_discon *) NULL) < 0)
	    ulog (LOG_ERROR, "t_rcvdis: %s", ztlierror ());
	  else
	    ulog (LOG_ERROR, "Connection refused");
	}
      return FALSE;
    }

  /* We've connected to the remote.  Push any desired modules.  */
  if (! ftli_push (qconn))
    return FALSE;      

  /* Handle the rest of the dialer sequence.  This is similar to
     fmodem_dial, and they should, perhaps, be combined somehow.  */
  if (pzdialer != NULL)
    {
      boolean ffirst;

      ffirst = TRUE;
      while (*pzdialer != NULL)
	{
	  int iuuconf;
	  struct uuconf_dialer *q;
	  struct uuconf_dialer s;
	  const char *ztoken;
	  boolean ftranslate;

	  if (! ffirst)
	    q = &s;
	  else
	    q = qdialer;

	  iuuconf = uuconf_dialer_info (puuconf, *pzdialer, q);
	  if (iuuconf == UUCONF_NOT_FOUND)
	    {
	      ulog (LOG_ERROR, "%s: Dialer not found", *pzdialer);
	      return FALSE;
	    }
	  else if (iuuconf != UUCONF_SUCCESS)
	    {
	      ulog_uuconf (LOG_ERROR, puuconf, iuuconf);
	      return FALSE;
	    }

	  ++pzdialer;
	  ztoken = *pzdialer;

	  ftranslate = FALSE;
	  if (ztoken == NULL
	      || strcmp (ztoken, "\\D") == 0)
	    ztoken = zphone;
	  else if (strcmp (ztoken, "\\T") == 0)
	    {
	      ztoken = zphone;
	      ftranslate = TRUE;
	    }

	  if (! fchat (qconn, puuconf, &q->uuconf_schat,
		       (const struct uuconf_system *) NULL, q,
		       zphone, ftranslate, qconn->qport->uuconf_zname,
		       (long) 0))
	    {
	      (void) uuconf_dialer_free (puuconf, q);
	      if (! ffirst)
		(void) uuconf_dialer_free (puuconf, qdialer);
	      return FALSE;
	    }

	  if (ffirst)
	    {
	      *ptdialerfound = DIALERFOUND_FREE;
	      ffirst = FALSE;
	    }
	  else
	    (void) uuconf_dialer_free (puuconf, q);

	  if (*pzdialer != NULL)
	    ++pzdialer;
	}
    }

  return TRUE;
}

#endif /* HAVE_TLI */