#!/usr/bin/perl

#   pppconfig: a text menu based utility for configuring ppp.
#
#   Copyright (C) 1999 John G. Hasler (john@dhh.gt.org)
#
#   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.
#
#   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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#   or contact the author.
#
#   On Debian systems the GNU General Public License can be found in
#   /usr/doc/copyright/GPL or /usr/share/common-licenses/GPL.

# This hack exists so that the program can run in the absence of gettext
# or POSIX.

BEGIN {
  eval "use Locale::gettext";
  $no_gettext = $@;
  eval "use POSIX";
  if ($no_gettext || $@) {
    eval 'sub gettext($) { return $_[0]; }';
  }
  else {
    setlocale(LC_MESSAGES, "");
    textdomain("pppconfig");
  }
}

$version = "2.0.5";

$etc = "/etc";
#$etc = "/u/home/john/pppconfig/pppconfig-2.0";
$ppppath = "$etc/ppp";
$pppconfig_dir = "/var/lib/pppconfig";
$pppresolv = "$ppppath/resolv";
$optionpath = "$ppppath/peers";
$chatpath = "$etc/chatscripts";

$ipdefault = $ipnumber = $route = $user_arg = $ispport = '';
$connectcmd = $authcmd = $debugcmd = $demand = $ispspeed = $ispauth = '';
$nullnull = $abortstring = $modemnull = $modeminit = $modemok = '';
$ispnumber = $atdx = $ispconnect = $isplogin = $ispname = '';
$ispprompt = $dns = $remotename = $ipparam = $ipparam_arg = '';
$isppassword = $prelogin = $postlogin = $postloginsend = '';
$ispnull = $usepeerdns = $ipcp_accept_local = $ipcp_accept_remote = '';
$persist = $idle = $idle_arg ='';


$ispCONNECT = "CONNECT";

# Global arrays
@chatarray = ();
@deletelist = ();
@optionarray = ();
@secrets = ();
@pap_secrets = ();
@chap_secrets = ();
@newuserlist = ();
%oldfiles = ();

$resolv_conf ="OK";
$maxoptionfile = 20000; # Arbitrary upper limits on option and chat files.
$maxchatfile = 2000;    # If they are bigger than this something is wrong.

$backtitle = gettext("\"GNU/Linux PPP Configuration Utility\"");

$ttyport="/dev/ttyS1";
$prev_opt="";
$user_provider="";

LOOP: foreach $opt (@ARGV) {
  $opt =~ /\-\-version/ && do {
    usage() if $#ARGV > 0;
    version();
  };
  $opt =~  /\-\-help/ && do {
    usage() if $#ARGV > 0;
    help();
  };
  $opt =~  /\-\-whiptail/ && do {
    usage() if $ui;
    $ui = "whiptail";
    next LOOP;
  };
  $opt =~  /\-\-dialog/ && do {
    usage() if $ui;
    $ui = "dialog";
    next LOOP;
  };
  $opt =~  /\-\-gdialog/ && do {
    usage() if $ui;
    $ui = "gdialog";
    next LOOP;
  };
  $opt =~  /\-\-kdialog/ && do {
    usage() if $ui;
    $ui = "kdialog";
    next LOOP;
  };
  $opt =~ /\-\-noname/ && do {
    usage() if $provider;
    $noname = 1;
    $provider = "provider";
    next LOOP;
  };
  $opt =~ /\-\-ttyport/ && do {
    $prev_opt="ttyport";
    next LOOP;
  };
  $opt =~ /\-\-provider/ && do {
    usage() if $provider;
    $prev_opt="provider";
    next LOOP;
  };

  if ($prev_opt=~/ttyport/){
  	$ttyport=$opt;
	$prev_opt="";
	next LOOP;
  }
  	
  if ($prev_opt=~/provider/){
	$provider=$opt;
	$prev_opt="";
	next LOOP;
  }

  print "NO OPITON\n";
  usage();
 
  next LOOP;
}


$ui = `which whiptail` ? "whiptail" : "dialog" unless $ui;

die gettext("No UI") unless `which $ui`;

die (gettext("You must be root to run this program.\n")) if( $> != 0 );
die(gettext("$etc/chatscripts does not exist.\n")) if( ! -d "$etc/chatscripts" );
die(gettext("$etc/ppp/peers does not exist.\n")) if( ! -d "$etc/ppp/peers" );

MAIN: do_action (); # This is the main loop.

# Make a dialog box.

sub dialogbox(@) {
  $type=shift(@_);
  @vars=@_;
  $text=shift( @vars );
  $title=shift( @vars ) if( $#vars >= 0 );
  undef $args;
  $args=join( ' ', @vars ) if( $#vars >= 0 );
  $item=`$ui '--title' $title '--backtitle' $backtitle $type $text 22 80 $args 2>&1 1>/dev/tty 0</dev/tty `;
  chomp $item; # For gdialog, which returns strings with newlines.
  $result = $?;
  $result = ($? >> 8);
  quit() if ($result == 255);
  die(gettext("Internal error ")) unless($result == 0 || $result == 1);
  return $item;
}

sub msgbox(@) {
  dialogbox( "\-\-msgbox", @_ );
}

sub infobox(@) {
  dialogbox( "\-\-infobox", @_ );
}

sub yesnobox(@) {
  dialogbox( "\-\-yesno", @_ );
}

sub noyesbox(@) {
  if ($ui =~ /whiptail|gdialog/) {
    dialogbox( "\-\-defaultno \-\-yesno ", @_ );
  }
  else {
    dialogbox( "\-\-yesno", @_ );
  }
}

sub inputbox(@) {
  dialogbox( "\-\-inputbox", @_ );
}

sub menu(@) {
  $text=shift( @_ );
  $title=shift( @_ );
  $menu_height=shift( @_ );
  dialogbox( ' --menu', $text, $title, $menu_height, @_ );
}

sub radiolist(@) {
  $text=shift( @_ );
  local $title=shift( @_ );
  $menu_height=shift( @_ );
  dialogbox( "\-\-radiolist", $text, $title, $menu_height, @_ );
}
# end of interface to whiptail

sub mkmenu {
  my ($a, $b, $c, $d, $e, $f, $h, $i, $j) = '';
  my $action = '';
  my @menuvar = '';
  my $menu = $_[0];
  local @previous_menu_stack = ();
 SWITCH: for( $menu ) {
    /^main/ && do {
      # This section sets up the main menu.
      @previous_menu_stack = ("main");
      @menuvar = (gettext("\"This is the PPP configuration utility.  It does not connect to your isp: it \
just configures ppp so that you can do so with a utility such as pon.  It \
will ask for the username, password, and phone number that your ISP gave \
you.  If your ISP uses PAP or CHAP, that is all you need.  If you must use \
a chat script, you will need to know how your ISP prompts for your username \
and password.  If you do not know what your ISP uses, try PAP.  Use the up \
and down arrow keys to move around the menus.  Hit ENTER to select an item. \
Use the TAB key to move from the menu to <OK> to <CANCEL> and back.  When \
you are ready to move on to the next menu go to <OK> and hit ENTER.  To go \
back to the main menu go to <CANCEL> and hit enter.\""),
gettext("\"Main Menu\""), 5, 
'"Create"', gettext("\"Create a connection\"")); 
      push @menuvar, '"Change"', gettext("\"Change a connection\""),
'"Delete"', gettext("\"Delete a connection\"") unless $noname;
      push @menuvar, '"Finished"', gettext("\"Finish and save files\"") if checkchanges("CHECK");
      push @menuvar, '\'--nocancel\'' unless $ui =~ /dialog/;
      last SWITCH;
    };

    /^previous_menu/ && do {
      # Pop previous menu if he hit "Previous".
      pop @previous_menu_stack;
      $menu = pop @previous_menu_stack;
      redo SWITCH;
    };
      
    /^method/ && do {
      # menu of connection methods
      my $authmethod = uc($$ispauth);
      @menuvar = (gettext("\"\
Please select the authentication method for this connection.  PAP is the \
method most often used in Windows 95, so if your ISP supports the NT or \
Win95 dial up client, try PAP.  The method is now set to $authmethod.\""),
gettext("\" Authentication Method for $provider\""), 6,
'"PAP"',  gettext("\"Peer Authentication Protocol\""),
'"Chat"', gettext("\"Use \"chat\" for login:/password: authentication\""),
'"CHAP"', gettext("\"Crypto Handshake Auth Protocol\""),
'" "',    '" "' );
      last SWITCH; 
    };
    # end of method block

    /^properties/ && do {    # list of variables about a connection
      # to be modified by the user.
      # Format the variables for display.
      $a = sprintf "%-20.20s", $$ispnumber =~ /at.*?d[p|t]([^'"]+)/i; #'
      $b = sprintf "%-20.20s", $$isplogin ? $$isplogin : "ogin:";
      $c = sprintf "%-20.20s", $$ispname; 
      $d = sprintf "%-20.20s", $$ispprompt ? $$ispprompt : "ssword:";
      $e = $$isppassword;
      $e =~ s/^\\q//;
      $e =~ s/"/\\"/g;
      $e = sprintf "%-20.20s", $e;
      $f = sprintf "%-20.20s", $$ispspeed;
      $g = sprintf "%-20.20s", $$ispport;
      $h = sprintf "%-20.20s", $$ispauth;
    
      @menuvar = (gettext("\"\
Please select the property you wish to modify, select \"Cancel\" to go back \
to start over, or select \"Finished\" to write out the changed files.\""),
gettext("\"Properties of $provider\""), 14,
                       "Number",    gettext("\"$a Telephone number\""));
      push @menuvar, ( "ISPLogin",  gettext("\"$b Login prompt\"" )) 
        if( uc($$ispauth) eq "CHAT" );
      push @menuvar, ( "User",      gettext("\"$c ISP user name\""));
      push @menuvar, ( "ISPPrompt", gettext("\"$d Password prompt\"" )) 
        if( uc($$ispauth) eq "CHAT" );
      push @menuvar, ( "Password",  gettext("\"$e ISP password\""),
                       "Speed",     gettext("\"$f Port speed\""),
                       "Com",       gettext("\"$g Modem com port\""),
	               "Method",    gettext("\"$h Authentication method\""),
                       '" "',       '" "',
                       "Advanced",  gettext("\"Advanced Options\""),
                       '" "',       '" "',
                       "Finished",  gettext("\"Write files and return to main menu.\""));
      last SWITCH; 
    };
    # end of properties block

    /^advanced/   && do {    # configure advanced properties
  if ($$usepeerdns eq "usepeerdns") {
    $dns = "dynamic";
  }
  elsif ($$ipparam eq "ipparam") {
    $dns = "static";
  }
  else {
    $dns = "none";
  }
      $a = sprintf "%-20.20s", $$ispconnect;
      $b = sprintf "%-20.20s", $$postlogin;
      $c = sprintf "%-20.20s", $$modeminit;
      $d = sprintf "%-20.20s", $$route;
      $e = sprintf "%-20.20s", $$ipdefault;
      $f = $$debugcmd ? "enabled" : "disabled";
      $g = sprintf "%-20.20s", $f;
      $h = sprintf "%-20.20s", $$prelogin;
      $i = sprintf "%-20.20s", $dns;
      $j = sprintf "%-20.20s", $$remotename_arg;
      $k = sprintf "%-20.20s", $$idle ? $$idle_arg : "none";
      $l = $$demand ? "enabled" : "disabled";
      $m = sprintf "%-20.20s", $l;
      $n = $$persist ? "enabled" : "disabled";
      $o = sprintf "%-20.20s", $n;

      @menuvar = (gettext("\"\
This menu allows you to change some of the more obscure settings.  Select \
the setting you wish to change, and select \"Previous\" when you are done. \
Use the arrow keys to scroll the list.\""),
gettext("\"Advanced Settings for $provider\""), 11,
                       '"Modeminit"',    gettext("\"$c Modem init string\""),
                       '"ISPConnect"',   gettext("\"$a Connect response\""),
                       '"Pre-Login"',    gettext("\"$h Pre-login chat\""),
                       '"Defaultroute"', gettext("\"$d Default route state\""),
                       '"Ipdefault"',    gettext("\"$e Set ip addresses\""),
	               '"Debug"',        gettext("\"$g Turn debugging on or off\""),
	               '"Demand"',       gettext("\"$m Turn demand dialing on or off\""));
      push @menuvar,  ('"Persist"',      gettext("\"$o Turn persist on or off\""))
	unless $$demand;
      push @menuvar,  ('"Nameservers"',  gettext("\"$i Change DNS\""));
      push @menuvar,  ('"Add-User"',     gettext("\"                     Add a ppp user\"")) if(getgrnam("dip"));

      push @menuvar,  ('"Post-Login"',   gettext("\"$b Post-login chat \""))
        if( uc($$ispauth) eq "CHAT" );
      push @menuvar,  ('"Remotename"',   gettext("\"$j Change remotename \""))
        unless( uc($$ispauth) eq "CHAT" );
      push @menuvar,  ('"Idle-timeout"', gettext("\"$k Idle timeout \""),
                       '" "',            '" "' );
      last SWITCH; };
    # end of Advanced block
    
    /^CANCEL/ && do {
      return "CANCEL";
      last SWITCH; };
    
  } # End of SWITCH

  push @menuvar, '"Previous"', ( gettext("\"Return to previous menu\"")) unless $menu eq "main";
  
  push @menuvar, ( ' "Quit" ', gettext("\"Exit this utility\""));
  do { $action = menu @menuvar } while $action eq ' ' ;
  # Put up the menu that we just constructed.
  # ' ' means that a blank line has been selected, so just loop.
  return "CANCEL" if ($result != 0); # He hit cancel: return to main menu.
  push @previous_menu_stack, $menu if $menu ne $previous_menu_stack[-1];
  return $action;
} # end of mkmenu

sub do_action() {
  my $action;
  my $menu = "main";
  my @previous_action_stack;
  my @previous_menu_stack = "main";
  while (1) {
    push @previous_menu_stack, $menu if $menu ne $previous_menu_stack[-1];
    $action = mkmenu( $menu );
    ACTION: for( $action ) {
      /^CANCEL/ && do {
	$menu = "main";
        last ACTION;
      };
      /^Previous/ && do {
#	$menu = "previous_menu";
	pop @previous_menu_stack;
	$menu = pop @previous_menu_stack;
	last ACTION;
      };
      /^Properties/ && do {
	$menu = "properties";
	last ACTION;
      };
      /^Advanced/ && do {
        $menu = "advanced";
	last ACTION;
      };
      /^Method/ && do {
	$menu = "method";
	last ACTION;
      };
      /^Change/ && do {
	$menu = changeConnection( $menu );
	last ACTION;
      };
      /^PAP/ && do {
	$menu = ispauth( "PAP", $menu );
	last ACTION;
      };
      /^CHAP/ && do {
	$menu = ispauth( "CHAP", $menu );
	last ACTION;
      };
      /^Chat/ && do { 
	$menu = ispauth( "Chat", $menu );
	last ACTION;
      };
      /^Nameservers/ && do { 
	$menu = getnameservers( $menu );
	last ACTION;
      };
	/^Add-User/ && do { 
	$menu = add_user( $menu );
	last ACTION;
      };
      /^ISPConnect/ && do { 
	$menu = ispconnect( $menu );
	last ACTION;
      };
      /^Pre-Login/ && do { 
	$menu = prelogin( $menu );
	last ACTION;
      };
      /^ISPLogin/ && do { 
	$menu = isplogin( $menu );
	last ACTION;
      };
      /^ISPPrompt/ && do { 
	$menu = ispprompt( $menu );
	last ACTION;
      };
      /^Post-Login/ && do {
	$menu = postlogin( $menu );
	last ACTION;
      };
      /^Password/ && do { 
	$menu = isppassword( $menu );
	last ACTION;
      };
      /^Com/ && do {
	$menu = ispport( $menu );
	last ACTION;
      };
      /^Defaultroute/ && do { 
	$menu = defaultroute( $menu );
	last ACTION;
      };
      /^Ipdefault/ && do { 
	$menu = ipdefault( $menu );
	last ACTION;
      };
      /^Speed/ && do {  
	$menu = ispspeed( $menu );
	last ACTION;
      };
      /^User/ && do { 
        $menu = ispname( $menu );
	last ACTION;
      };
      /^Number/ && do { 
	$menu = ispnumber( $menu );
	last ACTION;
      };
      /^Modeminit/ && do { 
	$menu = modeminit( $menu );
	last ACTION;
      };
      /^Finished/ && do {
	$menu = finish( $menu );
	last ACTION;
      };
      /^Create/ && do {
	$menu = newConnection( $menu );
	last ACTION;
      };
      /^Delete/ && do { 
	$menu = deleteconnection( $menu );
	last ACTION;
      };
      /^Debug/ && do { 
	$menu = debug( $menu );
	last ACTION;
      };
      /^Demand/ && do { 
	$menu = demand( $menu );
	last ACTION;
      };
      /^Persist/ && do { 
	$menu = persist( $menu );
	last ACTION;
      };
      /^Remotename/ && do { 
	$menu = remotename( $menu );
	last ACTION;
      };
      /^Idle-timeout/ && do { 
	$menu = idle_timeout( $menu );
	last ACTION;
      };
      /^Quit/ && do {
	$menu = quit( $menu );
	last ACTION;
      };
      /.*/ && do {
	die (gettext("Internal error: no such thing as $action, "));
      };
    }
  } # End of while(1)
} # End of do_action

sub ispconnect($) {	# the connection string sent by the modem
  $temp=inputbox(gettext("\"\
Enter the text of connect acknowledgement, if any.  This string will be \
sent when the CONNECT string is received from the modem.  Unless you know \
for sure that your ISP requires such an acknowledgement you should leave \
this as a null string: that is, \'\'.\
\""), gettext("\"Ack String\""), "\"$$ispconnect\"" );
  return "CANCEL" if( $result != 0 );
  $$ispconnect=$temp;
  return $_[0];
}

sub isplogin($) {	# the login prompt string sent by the ISP
  $temp=inputbox(gettext("\"\
Enter the text of the login prompt.  Chat will send your username in \
response.  The most common prompts are login: and username:.  Sometimes the \
first letter is capitalized and so we leave it off and match the rest of \
the word.  Sometimes the colon is omitted.  If you aren\'t sure, try ogin:.\
\""),
gettext("\"Login Prompt\""), "$$isplogin" ? "\"$$isplogin\"" : "ogin:" );
  return "CANCEL" if( $result != 0 );
  $$isplogin=$temp;
  return $_[0]; 
}

sub ispprompt($) {	# password prompt sent by the ISP
  $temp=inputbox(gettext("\"\
Enter the text of the password prompt.  Chat will send your password in \
response. The most common prompt is password:.  Sometimes the first letter \
is capitalized and so we leave it off and match the last part of the \
word. \
\""), gettext("\"Password Prompt\""), "$$ispprompt" ? "\"$$ispprompt\"" : "ssword:" );
  return "CANCEL" if( $result != 0 );
  $$ispprompt=$temp;
  return $_[0];
}

sub prelogin($) {	# optional pre-login chat
  $temp = inputbox(gettext("\"\
You probably do not need to put anything here.  Enter any additional input \
your isp requires before you log in.  If you need to make an entry, make \
the first entry the prompt you expect and the second the required response.  \
Example: your isp sends \'Server:\' and expect you to respond with \
\'trilobite\'.  You would put \'erver trilobite\' (without the quotes) \
here.  All entries must be separated by white space.  You can have more \
than one expect-send pair.\
 \""), gettext("\"Pre-Login\""), "\"$$prelogin\"" );
  return "CANCEL" if( $result != 0 );
  $$prelogin = $temp;
  return $_[0];
}

sub postlogin($) {	# post-login chat
  $temp = inputbox(gettext("\"\
You probably do not need to change this.  It is initially \'\' \\d\\c \
which tells chat to expect nothing, wait one second, and send nothing.  \
This gives your isp time to get ppp started.  If your isp requires any \
additional input after you have logged in you should put it here.  This may \
be a program name like ppp as a response to a menu prompt.  If you need to \
make an entry, make the first entry the prompt you expect and the second \
the required response.  Example: your isp sends \'Protocol\' and expect you \
to respond with \'ppp\'.  You would put \'otocol ppp\' (without the quotes) \
here.  Fields must be separated by white space.  You can have more than one \
expect-send pair.\
 \""), gettext("\"Post-Login\""), "\"$$postlogin\"" );
  return "CANCEL" if( $result != 0 );
  $$postlogin = $temp;
  return $_[0];
}

sub do_ops($) {
  my $temp;
  $temp = ispname($_[0]);
  return "CANCEL" if $temp eq "CANCEL";
  $temp = isppassword($_[0]);
  return "CANCEL" if $temp eq "CANCEL";
  $temp = ispspeed($_[0]);
  return  "CANCEL"if $temp eq "CANCEL";
  $temp = ispnumber($_[0]);
  return "CANCEL" if $temp eq "CANCEL";
  $temp = ispport($_[0]);
  return $temp;
}

sub ispname($) { # input the user name for the ppp account
  $temp=inputbox (gettext("\"\
Enter the username given to you by your ISP.\
\""),
gettext("\"User Name\""), "\"$$ispname\"");
  return "CANCEL" if ( $result != 0 );
  $$ispname = $temp;
  $$user_arg=$$ispname;
  return $_[0];
}

sub ispport($) { # identify the port the modem is on
  my (@ttys, $manual, $tty, $port, $lines, @array, $temp);
  my $good = 0;

  if ($$ispport =~ /ttyWP/){
  	return 0;
  }
  
  yesnobox(gettext("\"\
Answer \'yes\' to have the port your modem is on identified automatically.  \
It will take several seconds to test each serial port.  Answer \'no\' if \
you would rather enter the serial port yourself\
\
NOTE: If you are using WANPIPE Async/Sync ports (eg:/dev/ttyWP0)\
      skip this option and select the appropriate /dev/ttyWPX port \
      (X = TTY Minor Number) based on the TTY Minor number selected \
      during WANPIPE configuration. \""),
gettext("\"Choose Modem Config Method\""));
  if (! $result) { # true $result means no.
    if (!system("pidof", "pppd")) {
      msgbox(gettext("\"
Can\'t probe while pppd is running.\""));
      goto MANUAL;
    }
    $manual = "on";
    system ("clear");
    foreach $tty (grep /16[45]50/, (`setserial -g /dev/ttyS\* 2>/dev/null`)) {
      ($port) = $tty =~ /^(\/dev\/ttyS\d+)/;
      print gettext("Probing $port"), "\n";
      $temp = `pppd nodetach noauth nocrtscts $port connect \"chat -t1 \'\' AT OK\"`;
      $good = (grep /established/, $temp) ? "on" : "off";
      $manual = "off" if $good eq "on";
      push @ttys, ($port, "\" \"", $good);
    }
    $lines = $#ttys > 12 ? 5 : ($#ttys + 1)/3 + 1;
    @array = (gettext("\"\
Below is a list of all the serial ports that appear to have hardware \
that can be used for ppp.  One that seems to have a modem on it has \
been preselected.  If no modem was found \'Manual\' was preselected.  To \
accept the preselection just hit TAB and then ENTER.  Use the up and \
down arrow keys to move among the selections, and press the spacebar \
to select one.  When you are finished, use TAB to select <OK> and ENTER \
to move on to the next item. \""), gettext("\"Select Modem Port\""), $lines);
    push @array, @ttys;
    push @array, '"Manual"', gettext("\"Enter the port by hand. \""), $manual;
    $temp = radiolist @array;
    return "CANCEL" if ( $result != 0 ) ;
    if ($temp ne "Manual") {
      $$ispport = $temp;
      return $_[0];
    }
  }
MANUAL:  $temp=inputbox (gettext("\"\
Enter the port your modem is on. \
\
WANPIPE Async/Sync Serial Ports:\
	/dev/ttyWP0 used by WANPIPE device with TTY Minor=0.\
	/dev/ttyWP1 used by WANPIPE device with TTY Minor=1.\
\
Standard Async Serial Ports:\
	/dev/ttyS0 is COM1 in DOS. \
	/dev/ttyS1 is COM2 in DOS. \
	/dev/ttyS2 is COM3 in DOS. \
	/dev/ttyS3 is COM4 in DOS. \
\
/dev/ttyS1 is the most common.  Note that this must be typed exactly as \
shown.  Capitalization is important: ttyS1 is not the same as ttys1.\""),
gettext("\"Manually Select Modem Port\""), "\"$$ispport\"");
  return "CANCEL" if ( $result != 0 ) ;
  $$ispport = $temp;
  return $_[0];
}

sub defaultroute($) {
  if ( $$route eq "defaultroute" ) {
    $nodefaultroute="off";
    $ddefaultroute="on";
  }
  else {
    $nodefaultroute="on";
    $ddefaultroute="off";
  }
  $temp=radiolist (gettext("\"\
Enabling default routing tells your system that the way to reach hosts to \
which it is not directly connected is via your ISP.  This is almost certainly \
what you want.  Use the up and down arrow keys to move among the selections, \
and press  the spacebar to select one.  When you are finished, use TAB to \
select <OK> and ENTER to move on to the next item.\""),
gettext("\"Default Route\""), 2, 
'"defaultroute"', gettext("\"Enable default route\""), $ddefaultroute,
'"nodefaultroute"', gettext("\"Disable default route\""),  $nodefaultroute);
  return  "CANCEL"if ( $result != 0 );
  $$route = $temp;
  return $_[0];
}

sub ipdefault($) {
  $temp=inputbox (gettext("\"\
You almost certainly do not want to change this from the default value of \
noipdefault.  This not the place for your nameserver ip numbers.  It is the \
place for your ip number if and only if your ISP has assigned you a static \
one.  If you have been given only a local static ip, enter it with a colon \
at the end, like this: 192.168.1.2:  If you have been given both a local \
and a remote ip, enter the local ip, a colon, and the remote ip, like this: \
192.168.1.2:10.203.1.2 \""),
gettext("\"IP Numbers\""),  "\"$$ipdefault\"");
  return "CANCEL" if ( $result != 0 );
  $$ipdefault = $temp;
  return $_[0];
}

sub ispspeed($) { # get the port speed
  $temp=inputbox (gettext("\"\
Enter your modem port speed (e.g. 9600, 19200, 38400, 57600, 115200).  \
For WANPIPE async use 38400 ; otherwise I suggest that you leave it at 115200.\""),
gettext("\"Speed\""), "\"$$ispspeed\"");
  return "CANCEL" if ( $result != 0 );
  $$ispspeed = $temp;
  return $_[0];
}

sub modeminit($) {
  $temp=inputbox (gettext("\"\
Enter modem initialization string.  The default value is ATZ, which tells \
the modem to use it\'s default settings.  As most modems are shipped from \
the factory with default settings that are appropriate for ppp, I suggest \
you not change this.\""),
gettext("\"Modem Initialization\""), "\"$$modeminit\"");
  return  "CANCEL"if ( $result != 0 );
  $$modeminit = chatescape($temp);
  return $_[0];
}

sub ispnumber($) { # Are we using pulse or dial?
  ($openquote, $atdx, $number, $closequote) = $$ispnumber =~ /(^['"]??)(at[^'"]*?d[p|t])([^'"]+)(\1?$)/i;
  $pulse = $atdx =~ /dp/i ? "on" : "off";
  $tone = $pulse eq "on" ? "off" : "on";
  $temp=radiolist (gettext("\"\
Select method of dialing.  Since almost everyone has touch-tone, you should \
leave the dialing method set to tone unless you are sure you need \
pulse.  Use the up and down arrow keys to move among the selections, and \
press the spacebar to select one.  When you are finished, use TAB to \
select <OK> and ENTER to move on to the next item.\""),
gettext("\"Pulse or Tone\""), 2,
'"Tone"', '""', $tone,
'"Pulse"', '""' , $pulse);
  return "CANCEL" if ( $result != 0 );
  $atdx =~ s/dp/DT/i if ($temp eq "Tone" && $pulse); 
  $atdx =~ s/dt/DP/i if ($temp eq "Pulse" && $tone);
  # Now get the number.
  $number=inputbox (gettext("\"\
Enter the number to dial.  Don\'t include any dashes.  See your modem manual \
if you need to do anything unusual like dialing through a PBX.\""),
gettext("\"Phone Number\""), "\"$number\"");
  return "CANCEL" if ( $result != 0 );
  $temp = $openquote . $atdx . $number . $closequote;
  $$ispnumber = chatescape($temp);
  return $_[0];
}

sub isppassword($) {
  $d = $$isppassword;
  $d =~ s/^\\q//;
  $d =~ s/"/\\"/g;
  $temp = inputbox (gettext("\"\
Enter the password your ISP gave you.\""),
gettext("\"Password\""),
"\"$d\"");
  return "CANCEL" if ( $result != 0 );
  $$isppassword = ( uc($$ispauth) eq "CHAT" ) ? "\\q" . $temp : $temp;
  return $_[0];
}

sub ispauth(@) {
  return $_[1] if($_[0] eq $$ispauth);
  my $oldauth = $$ispauth;
  my $newauth = $_[0];
  $password = $$isppassword;
  if($newauth =~/AP/) {
    $password =~ s/^\\q// if $oldauth eq "chat";
    secrets_file("delete", $provider, $oldauth) unless ($oldauth eq "chat");
    secrets_file("get", $provider, $newauth) unless ($newauth eq "chat");
    $$ispauth = $newauth;
    $$ispconnect = "\\d\\c";
  }

 SWITCH: for ($_[0]) {
    /^PAP/ && do {
      $$postlogin = '';
      $$remotename = "remotename";
      $$remotename_arg = $provider;
      last SWITCH;
    };
    /^CHAP/ && do {
      $$postlogin = $$remotename = $$remotename_arg = '';
      last SWITCH;
    };
    /^Chat/ && do { # Builds a chat file
      my $temp = isplogin($newauth);
      return "CANCEL" if $temp eq "CANCEL";
      $temp = ispprompt($newauth);
      return "CANCEL" if $temp eq "CANCEL";
      secrets_file("delete", $provider, $oldauth);
      $$ispauth = "chat";
      $password = "\\q" . $password;
      $$ispconnect = "\'\'";
      $$postlogin = "\'\' \\d\\c";
      parse_chat();
      last SWITCH;
    };
  }
  $$isppassword = $password;
      for ($i=0; $i<=$#chatarray; ++$i) {

}
  return $_[1];
}

sub getname()  {
  local $temp = "provider";

  if ($provider){
	$temp = $provider;
	goto FINISH_WITH_NAME;
  }

getname: do {
    $temp=inputbox(gettext("\"\
Enter the name you wish to use to refer to this isp.  You will probably \
want to give the default name of \'provider\' to your primary isp.  That way, \
you can dial it by just giving the command \'pon\'.  Give each additional isp \
a unique name.  For example, you might call your employer \'theoffice\' and \
your university \'theschool\'.  Then you can connect to your isp with \'pon\', \
your office with \'pon theoffice\', and your university with \'pon theschool\'.\""),
gettext("\"Provider Name\""), "\"$temp\"" );
    return "CANCEL" if( $result != 0 );
  };
   if (do_files ( "test", $temp )) {
      noyesbox (gettext("\"This connection exists.  Do you want to overwrite it?\""),
gettext("\"Connection Exists\""));
      goto getname if( $result ); # true $result means no so go back to getname.
    }  
    
FINISH_WITH_NAME:
  $provider = $temp;
  $$remotename_arg = $provider if $$remotename;
  $$ipparam_arg = $provider if $$ipparam;
  return $temp;
}

sub finish($) {
# this is to tidy up things with the user and is in no way
# associated with any Finnish Connections ;)
  my $temp;
  msgbox(gettext("\"\
Finished configuring connection and writing changed files.  The chat \
strings for connecting to the ISP are in /etc/chatscripts/$provider, \
while the options for pppd are in /etc/ppp/peers/$provider.  You may \
edit these files by hand if you wish.  You will now have an opportunity \
to exit the program, configure another connection, or revise this or \
another one.\""),
gettext("\"Finished\""));
  $result = 0;
  if ($provider) {
    do_files( "put", $provider );
    unlink "$pppconfig_dir/$provider";
  }
  foreach $temp (@deletelist) {
    next if $temp eq $provider; # Don't delete the new provider by accident
    do_files("get", $temp);
    secrets_file("delete", $temp, $$ispauth) if(lc($$ispauth) ne "chat");
    rename("$optionpath/$temp", "$optionpath/$temp.bak");
    rename("$chatpath/$temp", "$chatpath/$temp.bak");
    rename("$pppresolv/$temp", "$pppresolv/$temp.bak");
    unlink "$pppconfig_dir/$temp";
  }

  foreach $temp (@newuserlist) {
    adduser($temp);
  }

  %oldfiles = ();
  @deletelist = ();
  @newuserlist = ();
  secrets_file("write");
  return "CANCEL";
}

sub newConnection($) {
# this sets up new connections by calling other functions to:
# - initialize a clean state by zeroing state variables
# - query the user for information about a connection
  $title=gettext("\"Create Connection\"");
 $temp = getname() unless $noname; # Get the name of this provider.
  return "CANCEL" if $temp eq "CANCEL";
  do_files( "init", $provider );
  # Get variables now that we know the name
  $temp = getnameservers( $_[0] );
  return "CANCEL" if $temp eq "CANCEL";
  $temp = mkmenu( "method" ); 	# Put up a menu of methods.
  return "previous_menu" if( $temp eq "Previous" );
  return quit() if( $temp eq "Quit" );
  # this starts the process of collecting all other
  # connection related information
  $temp = ispauth( $temp );
  return "CANCEL" if $temp eq "CANCEL";
  $temp = do_ops($temp);
  return "CANCEL" if $temp eq "CANCEL";
 
  return "properties";
}

sub changeConnection($) {
  # Change an existing connection.
  # - Get the names of all existing connections.
  # - Ask the user to select one.
  undef @files;
  $afiles='';
  local $temp;
  opendir OPTIONDIR, $optionpath;
  @optionfiles = readdir OPTIONDIR;
  closedir OPTIONDIR;
  foreach $entry ( @optionfiles ) {
    push @files, $entry if do_files( "test", $entry );
  }
  $afiles = ( join '" " " "', @files );
  $afiles = ( "\"$afiles\" \" \"" );
  do { 
    $temp = menu(gettext("\"Select connection to change.\""), gettext("\"Select a Connection\""), 14, $afiles );
  } while( $temp eq ' ' );
  return "CANCEL" if( $result != 0 || $afiles !~ /\w+/);
  $provider = $temp;
  $title="\"Change $provider\"";
  do_files( "get", $provider ); 
  # Get variables now that we know the name
  return  "properties";
}

sub deleteconnection($) {
  # Delete an existing connection.
  # - Get the names of all existing connections.
  # - Ask the user to select one.
  undef @files;
  $afiles='';
  local $temp;
  opendir OPTIONDIR, $optionpath;
  @optionfiles = readdir OPTIONDIR;
  closedir OPTIONDIR;
  foreach $entry ( @optionfiles ) {
    push @files, $entry if do_files( "test", $entry );
  }
  $afiles = ( join '" " " "', @files );
  $afiles = ( "\"$afiles\" \" \"" );
  do { 
    $temp = menu(gettext("\"\
Select connection to delete.\""), gettext("\"Delete a Connection\""), 14, $afiles );
  } while( $temp eq ' ' );
  return "CANCEL" if( $result != 0 || $afiles !~ /\w+/);
  push @deletelist, $temp;
  return $_[0];
}

sub quit($) {
  if (checkchanges( CHECK )) {
    noyesbox (gettext("\"\
Do you wish to quit without saving your changes?\""), gettext("\"Quit\""));
    if( $result ) {
      # true $result means no so go back to menu.
      return $_[0];
    }
  }
#  system(clear);
  exit(0);
}

sub debug($) {
  $a = $$debugcmd ? "enabled" : "disabled";
  yesnobox(gettext("\"\
Selecting YES will enable debugging.  Selecting NO will disable it. \
Debugging is presently $a.\""), gettext("\"Debug Command\""));
  if( $result ) { # true $result means no.
    $$debugcmd = '';
    $$connectcmd =~ s/chat +-v/chat/;
  }
  else {
    $$debugcmd = "debug";
    $$connectcmd =~ s/chat/chat -v/ if $$connectcmd !~ /chat +-v/;
  }
  return $_[0];
}

sub demand($) {
  $a = $$demand ? "enabled" : "disabled";
  yesnobox(gettext("\"\
Selecting YES will enable demand dialing for this provider.  Selecting NO \
will disable it.  Note that you will still need to start pppd with pon: \
pppconfig will not do that for you.  When you do so, pppd will go into the \
background and wait for you to attempt access something on the Net, and \
then dial up the ISP.  if you do enable demand dialing you will also want \
to set an idle-timeout so that the link will go down when it is idle \
Demand dialing is presently $a.\""), gettext("\"Demand Command\""));

  if( $result ) { # true $result means no.
    $$demand = '';
  }
  else {
    $$demand = "demand";
    $$persist = '';
  }
  return $_[0];
}

sub persist($) {
  $a = $$persist ? "enabled" : "disabled";
  yesnobox(gettext("\"\
Selecting YES will enable persist mode.  Selecting NO will disable it. \
This will cause pppd to keep trying until it connects and to try to \
reconnect if the connection goes down.  Persist is incompatible with demand \
dialing: enabling demand will disable persist. \
Persist is presently $a.\""), gettext("\"Persist Command\""));
  if( $result ) { # true $result means no.
    $$persist = '';
  }
  else {
    $$persist = "persist";
  }
  return $_[0];
}

# Get the nameservers.
# resolv_conf is initialized to "OK".
sub getnameservers($)  {
  my ($a, $b, $c);
  $a = $b = $c = "off";
  if ($$usepeerdns eq "usepeerdns") {
    $dns = "dynamic"; $b = "on";
  }
  elsif ($$ipparam eq "ipparam") {
    $dns = "static"; $a = "on";
  }
  else {
    $dns = "none"; $c = "on";
  }
my $method = radiolist(gettext("\"\
Choose a method.  \'Static\' means that the same nameservers will be used \
every time this provider is used.  You will be asked for the nameserver \
numbers in the next screen.  'Dynamic' means that pppd will automatically \
get the nameserver numbers each time you connect to this provider.  'None' \
means that DNS will be handled by other means, such as BIND (named) or \
manual editing of /etc/resolv.conf.  Use the up and down arrow keys to move \
among the selections, and press the spacebar \ to select one.  When you are \
finished, use TAB to select <OK> and ENTER \ to move on to the next item.\""), 
gettext("\"Configure Nameservers (DNS)\"") , 3,  
'"Static"', gettext("\"Use static DNS\""), $a, 
'"Dynamic"', gettext("\"Use dynamic DNS\""), $b,
'"None"', gettext("\"DNS will be handled by other means\""), $c );
      return "CANCEL" if( $result != 0 );

    SWITCH: for( $method ) {
	/Static/ && do {
	  my $ipnumber = inputbox(gettext("\"\
Enter the IP number for your primary nameserver.\""), gettext("\"IP number\""), '' );
	  return "CANCEL" if( $result );
	  # true $result means CANCEL so go back to main menu.

	  $NAMESERVER1 = "nameserver ".$ipnumber."\n" if $ipnumber;
	  $$usepeerdns = "";
	  $$ipparam = "ipparam";
	  $$ipparam_arg = $provider;
	  $dns = "static";
	  $resolv_conf="SAVE";
	  $ipnumber = inputbox(gettext("\"\
Enter the IP number for your secondary nameserver (if any).\""), gettext("\"IP number\""), '' );
	  return "CANCEL" if( $result );

	  $NAMESERVER2 = "nameserver ".$ipnumber."\n" if $ipnumber;
	  return $_[0];
	  last SWITCH;
	};
	/Dynamic/ && do {
	  $$usepeerdns = "usepeerdns";
	  $NAMESERVER1 = "";
	  $NAMESERVER2 = "";
	  $resolv_conf="SAVE";
	  $$ipparam = "ipparam";
	  $$ipparam_arg = $provider;
          $dns = "dynamic";
	  return $_[0];
	  last SWITCH;
	};
	/None/ && do {
	  $$usepeerdns = "";
          $$ipparam = "";
	  $$ipparam_arg = "";
	  $resolv_conf="OK";
          $dns = "none";
	  return $_[0];
	  last SWITCH;
	};
      }
    }

sub add_user($) {
  LOOP: $temp=inputbox (gettext("\"\
Enter the username of a user who you want to be able to start and stop ppp. \
She will be able to start any connection.  To remove a user run the program \
vigr and remove the user from the dip group. \""),
gettext("\"Add User \""),  "\"\"");
  return "CANCEL" if ( $result != 0 );
  unless (getpwnam $temp) { # Make sure the user exists.
    msgbox (gettext("\"\
No such user as $temp. \""));
    goto LOOP;
  }
  push @newuserlist, $temp;
  return $_[0];
}

sub adduser($) { # Called from finish() to actually add the user.
  `adduser --quiet @_[0] dip`;
}

sub remotename($) {
  $temp=inputbox(gettext("\"\
You probably don't want to change this.  Pppd uses the remotename as well \
as the username to find the right password in the secrets file.  The default \
remotename is the provider name.  This allows you to use the same username \
with different providers.  To disable the remotename option give a blank \
remotename.  The remotename option will be omitted from the provider file \
and a line with a * instead of a remotename will be put in the secrets file. \
\""), gettext("\"Remotename\""), "\"$$remotename_arg\"");
  return "CANCEL" if( $result != 0 );
  $$remotename_arg = $temp =~ /\w+/ ? $temp : "";;
  $$remotename = $$remotename_arg ? "remotename" : "";
  return $_[0];
}
	
sub idle_timeout($) {
  $temp=inputbox(gettext("\"\
If you want this PPP link to shut down automatically when it has been idle \
for a certain number of seconds, put that number here.  Leave this blank \
if you want no idle shutdown at all. \
\""), gettext("\"Idle Timeout\""), "\"$$idle_arg\"");
  return "CANCEL" if( $result != 0 );
  $$idle_arg = $temp =~ /\w+/ ? $temp : "";;
  $$idle = $$idle_arg ? "idle" : "";
  return $_[0];
}

sub putnameservers () {
  # Fix up resolv.conf if needed.
  return if( $resolv_conf eq "OK" );
  system "touch $pppresolv/$provider";
  open( RESOLV, ">$pppresolv/$provider" ) or die(gettext("Couldn\'t open $pppresolv/$provider.\n"));
  chmod 0644, "$pppresolv/$provider" if( $resolv_conf eq "NONE" );
  print RESOLV ($NAMESERVER1, $NAMESERVER2);
  # Put some nameservers in it.
  $resolv_conf="OK";
  close RESOLV;
  return;
}

# Static vars for checkchanges()
my $optionchecksum = 0;
my $chatchecksum = 0;
my $papchecksum = checksum(@pap_secrets);
my $chapchecksum = checksum(@chap_secrets);

sub checkchanges(@) {
# If called with CHECK, compare checksums for the arrays with those
# computed when the files were read in.  Return true if any have changed.
# If called with SET initialize the checksums.
 SWITCH: for( $_[0] ) {
    /CHECK/ && do {
      return (($optionchecksum != checksum (@optionarray)) ||
	      ($chatchecksum != checksum (@chatarray)) ||
	      ($papchecksum != checksum (@pap_secrets)) ||
	      ($chapchecksum != checksum (@chap_secrets)) ||
	      ($resolv_conf eq "SAVE")) ||
              ($#deletelist != -1) ||
	      ($#newuserlist != -1);
      last SWITCH;
    };
    /SET/ && do {
      $optionchecksum = checksum (@optionarray);
      $chatchecksum = checksum (@chatarray);
      return;
      last SWITCH;
    };
  }
}
sub checksum(@) {
# Compute a 32 bit checksum.
return (unpack ("%32C*", (join '', @_)));
}

sub chatescape(@) {
# Just inserts quotes for now.
  return $_[0] if $_[0] !~ / +/ || $_[0] =~ /^'.*'$/ || $_[0] =~ /^".*"$/;
  return '\'' . $_[0] . '\'';
}

sub tokenize_options(@) {
  # Parse the file into comments, quoted strings, unquoted strings
  # and whitespace while keeping everything in order.  This will allow
  # us to edit the file in place and write it back out without mucking
  # up the sysadmin's changes.
  my @array;
  while( $_[0] =~ /(^#.*\n)|('[^']*')|("[^"]*")|(\S+)|(\s+)/gom ) {
    @array = (@array, $&);
  }
  return @array;
}

sub tokenize_chat(@) {
  # Parse the file into comments, quoted strings, unquoted strings
  # and whitespace while keeping everything in order.  This will allow
  # us to edit the file in place and write it back out.  Handle
  # ispauth specially.
  my @array;
  while( $_[0] =~ /(^# ispauth\s+)|(^#.*\n)|(\S*?'[^']*')|("[^"]*")|(\S+)|(\s+)/gomi ) {
    @array = (@array, $&);
  }
  return @array;
}

sub parse_options(@) {
  # Point the option variables at the correct fields in the optionarray
  # filled in by tokenize_options() so that they can be edited in place.
  my $dquad = "\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}";
  for( my $i = 0; $i < $#optionarray; $i++ ) {
  SWITCH: for( $optionarray[$i] ) {
      /^noipdefault$/o && do {
	$ipdefault = \$optionarray[$i];
	last SWITCH;
      };
      /($dquad:)|(:$dquad)|($dquad:$dquad)/o && do {
	$ipnumber = \$optionarray[$i];
	last SWITCH;
      };
      /^(no)??defaultroute$/o && do {
	$route = \$optionarray[$i];
	last SWITCH;
      };
      /^user$/o && do {
	$i += 2; # Skip over whitespace.
	$user_arg = \$optionarray[$i];
	last SWITCH;
      };
      /^(\/dev\/)??tty\w[0-9]{1,2}?$|^\/dev\/modem$/o && do {
	$ispport = \$optionarray[$i];
	last SWITCH;
      };
      /^connect$/o && do {
	$i += 2; # Skip over whitespace.
	$connectcmd = \$optionarray[$i];
	last SWITCH;
      };
      /^(no)??auth$/o && do {
	$authcmd = \$optionarray[$i];
	last SWITCH;
      };
      /^debug$/o && do {
	$debugcmd = \$optionarray[$i];
	last SWITCH;
      };
      /^demand$/o && do {
	$demand = \$optionarray[$i];
	last SWITCH;
      };
#      /^ipcp-accept-local$/o && do {
#	$ipcp_accept_local = \$optionarray[$i];
#	last SWITCH;
#      };
#      /^ipcp-accept-remote$/o && do {
#	$ipcp_accept_remote = \$optionarray[$i];
#	last SWITCH;
#      };
      /^persist$/o && do {
	$persist = \$optionarray[$i];
	last SWITCH;
      };
      /^[0-9]{3,6}$/o && do {
	$ispspeed = \$optionarray[$i];
	last SWITCH;
      };
      /^usepeerdns$/o && do {
	$usepeerdns = \$optionarray[$i];
	last SWITCH;
      };
      /^remotename$/o && do {
	$remotename = \$optionarray[$i];
	$i += 2; # Skip over whitespace.
	$remotename_arg = \$optionarray[$i];
	last SWITCH;
      };
      /^idle$/o && do {
	$idle = \$optionarray[$i];
	$i += 2; # Skip over whitespace.
	$idle_arg = \$optionarray[$i];
	last SWITCH;
      };
      /^ipparam$/o && do {
	$ipparam = \$optionarray[$i];
	$i += 2; # Skip over whitespace.
	$ipparam_arg = \$optionarray[$i];
	last SWITCH;
      };

    }
  }
}

sub parse_chat(@) {
  # Point the chat variables at the correct fields in the chatarray
  # filled in by tokenize_chat() so that they can be edited in place.
  $i = 0;
  $i++ until $chatarray[$i] =~ /^# ispauth/o || $i > $#chatarray;
    parse_field( $i, "# ispauth ", "ispauth", '', "nullnull" );
  $i++ until $chatarray[$i] =~ /^# abortstring$/o || $i > $#chatarray;
    parse_field( $i, "# abortstring\n", "abortstring", '' );
  $i++ until $chatarray[$i] =~ /^# modeminit$/o || $i > $#chatarray;
    parse_field( $i, "# modeminit\n", "modemnull", " ", "modeminit" );
  $i++ until $chatarray[$i] =~ /^# ispnumber$/o || $i > $#chatarray;
    parse_field( $i, "# ispconnect\n", "modemok", '', "ispnumber" );
  $i++ until $chatarray[$i] =~ /^# ispconnect$/o || $i > $#chatarray;
    parse_field( $i, "# ispconnect\n", "ispCONNECT", " ", "ispconnect" );
  $i++ until $chatarray[$i] =~ /^# prelogin$/o || $i > $#chatarray;
    parse_field( $i, "# prelogin\n", "prelogin", '' );
  $i++ until $chatarray[$i] =~ /^# ispname$/o || $i > $#chatarray;
    parse_field( $i, "# ispname\n", "isplogin", " ", "ispname" );
  $i++ until $chatarray[$i] =~ /^# isppassword$/o || $i > $#chatarray;
    parse_field( $i, "# isppassword\n", "ispprompt", " ", "isppassword" );
  $i++ until $chatarray[$i] =~ /^# postlogin$/o || $i > $#chatarray;
    parse_field( $i, "# postlogin\n", "postlogin", '' );
  $i++ until $chatarray[$i] =~ /^# end/o || $i > $#chatarray;
}

sub parse_field(@) { # Call with index, tag, expect var, separator, send var.
# Point the variable at the right fields, splicing in empty fields as required.

  $j = $_[0]+1;
  $j++ until( $chatarray[$j] =~ /\S+/ || $j > $#chatarray );
  # Find the first non-empty field.
  if( $chatarray[$j] =~ /^#.*/ ) {
  # If it is a comment (a tag, we assume) then there are no strings.
      splice( @chatarray, $_[0], $j - $_[0], ( $_[1], '' , $_[3], '', "\n" ));
      # So splice in some null fields to point the variables at.
      $j = $_[0] + 1;
      ${"$_[2]"} = \$chatarray[$j];
      ${"$_[4]"} = \$chatarray[$j + 2] if( $#_ > 3 );
    }
  else {
    if( $#_ < 4 ) {
    # If only one var was supplied, splice everything up to the next comment
    # together and point the variable at the result.
      $j++ until( $chatarray[$j + 2] =~ /^#.*/ || $j > $#chatarray );
      splice( @chatarray, $_[0] + 1, $j - $_[0], join( "", (@chatarray[$_[0]+1...$j] )));
      ${"$_[2]"} = \$chatarray[$_[0] + 1];
      return;
    }
    ${"$_[2]"} = \$chatarray[$j];
    $j++;
    $j++ until ($chatarray[$j] =~ /\S+/ || $j > $#chatarray);
    $j -= 2 if( $chatarray[$j] =~ /^#.*/ );
    ${"$_[4]"} = \$chatarray[$j];
  }
}
  
# Static vars for do_files
my @newoptions = ();
  
sub do_files(@) { # Call with 'command, provider'.
  my $provider = $_[1];
  my $optionfile = "$optionpath/$_[1]";
  my $chatfile = "$chatpath/$_[1]";
  my $options = '';
  my $chat = '';
  my $filesize = '';
  my $line = '';
  
 SWITCH: for ($_[0]) {
    
    /test/ && do {
      # Are there valid files for this provider?
      return 0 if grep /$provider$/, @deletelist;
      $filesize = -s $optionfile;
      return 0 if $filesize == 0 or $filesize > $maxoptionfile;
      $filesize = -s $chatfile;
      return 0 if $filesize == 0 or $filesize > $maxchatfile;
      open( OPTIONFILE, "<$optionfile" ) or return 0;
      $line = <OPTIONFILE>;
      close OPTIONFILE;
      grep( /pppconfig/, $line ) or return 0;
      open( CHATFILE, "<$chatfile" ) or return 0;
      undef $/;
      $chat = <CHATFILE>; # Read the entire file into a string.
      $/ = "\n";
      close CHATFILE;
      
      # Make sure the file contains all the tags in the correct order.
      if ($chat =~ /.*?pppconfig.*?\# ispauth.*?\# abortstring.*?\# modeminit.*?\# ispnumber.*?\# ispconnect.*?\# prelogin.*?\# ispname.*?\# isppassword.*?\# postlogin.*/so)
      {
	return 1;
      }
      else { 
	return oldfiles ("test", $provider);
      }
    };

  /init/ && do { 
      my $i;
      for( $i = 0; $i < 300; $i++ ) {
        $optionarray[$i] = '';
      }
      # Load the options variable with defaults.
      $options = "# This optionfile was generated by pppconfig $version. 
# 
#
hide-password 
noauth
connect \"/usr/sbin/chat -v -f $chatpath/$provider\"
debug
$ttyport
38400
defaultroute
noipdefault 
user replace_with_your_login_name
remotename $provider
ipparam $provider
";

      newoptions();

      # And then tokenize and parse them just as we would if they had been
      # read from a file.
      undef $/;
      @optionarray = tokenize_options( $options );
      $/ = "\n";
      parse_options( @optionarray );      
      chatinit();
      return 0;
    };

    /get/ && do {
      open( OPTIONFILE, "<$optionfile" ) or die( gettext("Can\'t open $optionfile.\n"));
      # Get an exclusive lock.  Return if we can't get it.
      flock( OPTIONFILE, 6 ) or die( gettext("Can\'t lock $optionfile.\n"));
      undef $/;
      my $options = <OPTIONFILE>; # Read the entire file into a string.
      $/ = "\n";
      do {} while chomp $options;
      $options .= "\n";
      close OPTIONFILE;
      flock( OPTIONFILE, 8 ); # Unlock

      newoptions();

      unshift @optionarray, tokenize_options( $options );

      parse_options( @optionarray );


      if (exists $oldfiles{$provider}) {
	oldfiles("get", $provider);
      }
      else {
	open( CHATFILE, "<$chatfile" ) or die(gettext("Can\'t open $chatfile.\n"));
	# Get an exclusive lock.  Return if we can't get it.
	flock( CHATFILE, 6 ) or die(gettext("Can\'t lock $chatfile.\n"));
	undef $/;
	$chat = <CHATFILE>; # Read the entire file into a string.
	$/ = "\n";
	close CHATFILE;
	flock( CHATFILE, 8 ); # unlock
	@chatarray = tokenize_chat( $chat );
	parse_chat( @chatarray );
      }
      if( uc($$ispauth) eq "PAP" || uc($$ispauth) eq "CHAP" ) {
        secrets_file( "get", $provider, $$ispauth );
      }
      checkchanges( SET );
    };
  
    /put/ && do {
for( $i=1; $i<$#newoptions; $i+=2) {
  push( @optionarray, $newoptions[$i-1], $newoptions[$i]) if( $newoptions[$i] );
}
      # Write out the files for this provider.  Write to a temporary file and
      # then rename the temporary with the name of the original file after renaming 
      # original (if it exists) with a '.bak' suffix.  This makes the operation 
      # atomic while not disturbing processes which may have the file open for 
      # reading (nobody else should be writing).
      if ( uc($$ispauth) eq "PAP" || uc($$ispauth) eq "CHAP" ) {
        secrets_file("put", $provider, $$ispauth);
	trimchat ();
      }
      undef $\;
      writefile(@optionarray, $optionfile, 0640);
      writefile(@chatarray, $chatfile, 0640);
       putnameservers ();
       checkchanges("SET");
      return;
    };
  }
} # End of do_files

sub newoptions() {
  my $i;
  for( $i = 0; $i < 300; $i++ ) {
    $optionarray[$i] = '';
  }      
  $optionarray[-1] = "\n";
  
  $i = 0;
  
  $newoptions[$i++] = "\n";
  $ipdefault = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $ipnumber = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $route = \$newoptions[$i++];
  $newoptions[$i++] = "\nuser ";
  $user_arg = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $ispport = \$newoptions[$i++];
  $newoptions[$i++] = "\nconnect ";
  $connectcmd = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $authcmd = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $debugcmd = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $demand = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
#  $ipcp_accept_local = \$newoptions[$i++];
#  $newoptions[$i++] = "\n";
#  $ipcp_accept_remote = \$newoptions[$i++];
#  $newoptions[$i++] = "\n";
  $persist = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $ispspeed = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $usepeerdns = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $remotename = \$newoptions[$i++];
  $newoptions[$i++] = " ";
  $remotename_arg = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $ipparam = \$newoptions[$i++];
  $newoptions[$i++] = " ";
  $ipparam_arg = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
  $idle = \$newoptions[$i++];
  $newoptions[$i++] = " ";
  $idle_arg = \$newoptions[$i++];
  $newoptions[$i++] = "\n";
} # End of newoptions()

sub chatinit(@) {
  my $chat;
  # Load the chat variable with defaults.
  $chat = "# This chatfile was generated by pppconfig $version.
# Please do not delete any of the comments.  Pppconfig needs them.
# 
# ispauth chat
# abortstring
ABORT BUSY ABORT \'NO CARRIER\' ABORT VOICE ABORT \'NO DIALTONE\' ABORT \'NO DIAL TONE\' ABORT \'NO ANSWER\'
# modeminit
\'\' ATZ
# ispnumber
OK-AT-OK ATDTreplace_with_number
# ispconnect
CONNECT \'\'
# prelogin
# ispname
ogin: replace_with_name
# isppassword
ssword: replace_with_password
# postlogin
\'\' \\d\\c
# end of pppconfig stuff
";
  # And tokenize and parse them.
  undef $/;
  @chatarray = tokenize_chat( $chat );
  $/ = "\n";
  parse_chat( @chatarray );
  checkchanges( SET );
  return 0;
}

sub oldfiles(@) {
  my $oldchat = '';
  my @oldchatarray = ();
  my $provider = $_[1];
  open (OLDFILE, "<$pppconfig_dir/$provider") || return 0;
  undef $/;
  $oldchat = <OLDFILE>; # Read the entire file into a string.
  $/ = "\n";
  @oldchatarray = split /\n/, $oldchat;
  return 0 if uc($oldchatarray[0]) !~ /CHAT|PAP|CHAP/;
  return 0 if uc($oldchatarray[0]) =~ /PAP|CHAP/ &&  $#oldchatarray != 3;
  return 0 if uc($oldchatarray[0]) eq "CHAT" && $#oldchatarray != 9;
  if ($_[0] eq "test") {
    $oldfiles{$provider} = 1;
    return 1;
  }
  chatinit();
  $$ispauth = $oldchatarray[0];
  $$modeminit = $oldchatarray[1];
  $$atdx = $oldchatarray[2];
  $$number = $oldchatarray[3];
  if (uc($oldchatarray[0]) eq "CHAT") {
    $$ispconnect = $oldchatarray[4];
    $$isplogin = $oldchatarray[5];
    $$ispname = $oldchatarray[6];
    $$ispprompt = $oldchatarray[7];
    $$isppassword = $oldchatarray[8];
    $$postlogin = $oldchatarray[9];
  }
  else {
    $$ispconnect = "\\d\\c";
    $$isplogin = '';
    $$ispname = '';
    $$ispprompt = '';
    $$isppassword = '';
  }
  $$ispnumber = $$atdx . $$number;
  $$remotename = "remotename";
  $$remotename_arg = $provider;
  return 1;
}

# Static vars for secretsFile
my ($user_key, $remote_key);
my $secrets_pointer = -1; 

sub secrets_file(@) { # Call with command, provider, authtype.
  my $secrettype = lc($_[2]);
  my $secretsfile = "$ppppath/$secrettype-secrets";
  my ($secretstring, $return);
  return 1 if $secrettype eq "chat";
  $secrets = ($secrettype eq "pap") ? \@pap_secrets : \@chap_secrets;
  do { open(SECRETSFILE, "<$secretsfile") or die(gettext("Can\'t open $secretsfile.\n"));
       # Get an exclusive lock.  Exit if we can't get it.

       flock (SECRETSFILE, 6) or die(gettext("Can\'t lock $secretsfile.\n"));
       undef $/;
       $secretstring = <SECRETSFILE>; # Read the entire file into a string.
       $/ = "\n";
       flock (SECRETSFILE, 8); # Unlock
       close SECRETSFILE;
       @$secrets = tokenize_options($secretstring);
       $papchecksum = checksum (@pap_secrets) if ($secrettype eq "pap");
       $chapchecksum = checksum (@chap_secrets) if ($secrettype eq "chap");
     } unless (@$secrets || $_[0] eq "write");

 SWITCH: for ($_[0]) {

    /get/ && do {
      $$ispname = $$user_arg;
      $remote_key = $secrettype eq "pap" ? $$remotename_arg : '\*';
      for ( $i = 0; $i < $#$secrets; $i++ ) {
	if ($$secrets[$i] =~ /$$user_arg/ && $$secrets[$i + 1] =~ /\s+/ 
	    && $$secrets[$i + 2] =~ /$remote_key/) {
	  $secrets_pointer = $i;
          $user_key = \$$secrets[$i];
          $remote_key = \$$secrets[$i + 2];
	  $isppassword = \$$secrets[$i + 4];
	  return 1;
	}
      }
      $return = $$secrets[-1] =~/\n/ ? '' : "\n";
      push @$secrets, ($return, $$ispname, " ", $$remote_key,
		       " ", "replace_with_password");
      $user_key = \$$secrets[$#$secrets - 4];
      $remote_key = \$$secrets[$#$secrets - 2];
      $isppassword = \$$secrets[$#$secrets];
      $secrets_pointer = $#$secrets - 4;
      return 1;
    };
    
    /put/ && do {
	$$user_key = $$ispname;
	$$remote_key = $$remotename ? $$remotename_arg : '*';
      return 1;
    };

    /write/ && do {
      if ($papchecksum != checksum (@pap_secrets)) {
	writefile(@pap_secrets, "$ppppath/pap-secrets", 0600);
	$papchecksum = checksum (@pap_secrets);
      }
      
      if ($chapchecksum != checksum (@chap_secrets)) {
	writefile(@chap_secrets, "$ppppath/chap-secrets", 0600);
	$chapchecksum = checksum (@chap_secrets);
      }
      return 1;
    };

    /delete/ && do {
      return 0 if($secrets_pointer == -1);
      if(($$remote_key eq '*' ) 
	 && ($$secrets[$secrets_pointer - 1] =~ /\#.+pppconfig for $_[1]/)) {
	  $$secrets[$secrets_pointer - 1] = '';
	}
      else { # We can't be sure this line is not used elsewhere.
	return 1 if($$remote_key eq '*' );
      }

      for ($i = $secrets_pointer; ($$secrets[$i] !~ /\n/) && ($i <= $#$secrets); ++$i) {
	$$secrets[$i] = '';
      }
      return 1;
    };
  }
} # End of secrets_file

sub trimchat { # Fix up chat script for pap/chap.
$i= 0; $i++ until ($chatarray[$i] =~ /^# ispname/o || $i == $#chattarray);
  do {
    $i++;
    $chatarray[$i] = '' unless ($chatarray[$i] =~ /^#/); 
  }
  until ($chatarray[$i] =~ /^# postlogin/o || $i == $#chattarray);
}

sub writefile(@) {
  # Call with @data, filename, mode,
  # Write out a file.  Write to a temporary file and then rename the
  # temporary with the name of the original file after renaming original
  # (if it exists) with a '.bak' suffix.  This makes the operation atomic
  # while not disturbing processes which may have the file open for reading
  # (nobody else should be writing).
  $mode = pop @_;
  $filename = pop @_;
  $data = join '', @_;
  $data =~ s/\n{2,}/\n/gso; # Remove blank lines
  open (TEMPFILE, ">$filename.$$") or die(gettext("Couldn\'t open $filename.$$.\n"));
  print (TEMPFILE $data) or die(gettext("Couldn\'t print to $filename.$$.\n"));
  close TEMPFILE;
  rename ("$filename", "$filename.bak") or die(gettext("Couldn\'t rename $filename.\n")) if -f "$filename"; 
  rename ("$filename.$$", "$filename") or die(gettext("Couldn\'t rename $filename.$$.\n"));
  chmod $mode, "$filename";
}

sub usage() {
  die(gettext("Usage: pppconfig [--version] | [--help] | [[--dialog]\
 | [--ttyport ttyport_name] | [--provider provider_name ]\
\'--version\' prints the version. \'--help\' prints a help message.\
\'--dialog\' uses dialog instead of whiptail.  \'--noname\' forces \
\'--ttyport\' serial port /dev/ttyS1 or /dev/ttyWP0 \
\'--provider\' connection name eg: isp_wanpipe1.\n"));
}

sub help() {
  print "pppconfig $version
\n" ;
  print (gettext("pppconfig is an interactive, menu driven utility to help automate setting \
up a dial up ppp connection.  It currently supports PAP, CHAP, and chat \
authentication.  It uses the standard pppd configuration files.  It does \
not make a connection to your isp, it just configures your system so that \
you can do so with a utility such as pon.  It can detect your modem, and 
it can configure ppp for dynamic dns, multiple ISP's and demand dialing. \
\
Before running pppconfig you should know what sort of authentication your \
isp requires, the username and password that they want you to use, and the \
phone number.  If they require you to use chat authentication, you will \
also need to know the login and password prompts and any other prompts and \
responses required for login.  If you can\'t get this information from your \
isp you could try dialing in with minicom and working through the procedure \
until you get the garbage that indicates that ppp has started on the other \
end. \
\
Since pppconfig makes changes in system configuration files, you must be \
logged in as root or use sudo to run it. \
 \n"));
  usage();
}

sub version() {
  die("pppconfig $version\n");
}
