<?php
/* Functions for Networking */

function mask2cidr($mask){
  $long = ip2long($mask);
  $base = ip2long('255.255.255.255');
  return 32-log(($long ^ $base)+1,2);
}

/* Functions to write ini files */

function write_php_ini($array, $file) {
    $res = array();
    foreach($array as $key => $val) {
        if(is_array($val)) {
            $res[] = "[$key]";
            foreach($val as $skey => $sval) $res[] = "$skey = ".(is_numeric($sval) ? $sval : '"'.$sval.'"');
        }
        else $res[] = "$key = ".(is_numeric($val) ? $val : '"'.$val.'"');
    }
    if(safefilerewrite($file, implode("\r\n", $res))) {
        return true;
    } else {
        return false;
    }
}

function safefilerewrite($fileName, $dataToSave) {
    if ($fp = fopen($fileName, 'w')) {
        $startTime = microtime(TRUE);
        do {
            $canWrite = flock($fp, LOCK_EX);
            // If lock not obtained sleep for 0 - 100 milliseconds, to avoid collision and CPU load
            if(!$canWrite) usleep(round(rand(0, 100)*1000));
        } while ((!$canWrite)and((microtime(TRUE)-$startTime) < 5));

        //file was locked so now we can store information
        if ($canWrite) {
            fwrite($fp, $dataToSave);
            flock($fp, LOCK_UN);
        }
        fclose($fp);
        return true;
    } else {
        return false;
    }
}



/**
*
* Add CSRF Token to form
*
*/
function CSRFToken() {
?>
<input id="csrf_token" type="hidden" name="csrf_token" value="<?php echo htmlspecialchars($_SESSION['csrf_token'], ENT_QUOTES);; ?>" />
<?php
}

/**
*
* Validate CSRF Token
*
*/
function CSRFValidate() {
  if ( hash_equals($_POST['csrf_token'], $_SESSION['csrf_token']) ) {
    return true;
  } else {
    error_log('CSRF violation');
    return false;
  }
}

/**
* Test whether array is associative
*/
function isAssoc($arr) {
  return array_keys($arr) !== range(0, count($arr) - 1);
}

/**
*
* Display a selector field for a form. Arguments are:
*   $name:     Field name
*   $options:  Array of options
*   $selected: Selected option (optional)
*       If $options is an associative array this should be the key
*
*/
function SelectorOptions($name, $options, $selected = null, $id = null) {
  echo '<select class="form-control" name="'.htmlspecialchars($name, ENT_QUOTES).'"';
  if (isset($id)) {
      echo ' id="' . htmlspecialchars($id, ENT_QUOTES) .'"';
  }

  echo '>' , PHP_EOL;
  foreach ( $options as $opt => $label) {
    $select = '';
    $key = isAssoc($options) ? $opt : $label;
    if( $key == $selected ) {
      $select = ' selected="selected"';
    }

    echo '<option value="'.htmlspecialchars($key, ENT_QUOTES).'"'.$select.'>'.
            htmlspecialchars($label, ENT_QUOTES).'</option>' , PHP_EOL;
  }

  echo '</select>' , PHP_EOL;
}

/**
*
* @param string $input
* @param string $string
* @param int $offset
* @param string $separator
* @return $string
*/
function GetDistString( $input,$string,$offset,$separator ) {
	$string = substr( $input,strpos( $input,$string )+$offset,strpos( substr( $input,strpos( $input,$string )+$offset ), $separator ) );
	return $string;
}

/**
*
* @param array $arrConfig
* @return $config
*/
function ParseConfig( $arrConfig ) {
	$config = array();
	foreach( $arrConfig as $line ) {
		$line = trim($line);
		if( $line != "" && $line[0] != "#" ) {
			$arrLine = explode( "=",$line );
			$config[$arrLine[0]] = ( count($arrLine) > 1 ? $arrLine[1] : true );
		}
	}
	return $config;
}

/**
*
* @param string $freq
* @return $channel
*/
function ConvertToChannel( $freq ) {
  if ($freq >= 2412 && $freq <= 2484) {
    $channel = ($freq - 2407)/5;
  } elseif ($freq >= 4915 && $freq <= 4980) {
    $channel = ($freq - 4910)/5 + 182;
  } elseif ($freq >= 5035 && $freq <= 5865) {
    $channel = ($freq - 5030)/5 + 6;
  } else {
    $channel = -1;
  }
  if ($channel >= 1 && $channel <= 196) {
    return $channel;
  } else {
    return 'Invalid Channel';
  }
}

/**
* Converts WPA security string to readable format
* @param string $security
* @return string
*/
function ConvertToSecurity( $security ) {
  $options = array();
  preg_match_all('/\[([^\]]+)\]/s', $security, $matches);
  foreach($matches[1] as $match) {
    if (preg_match('/^(WPA\d?)/', $match, $protocol_match)) {
      $protocol = $protocol_match[1];
      $matchArr = explode('-', $match);
      if (count($matchArr) > 2) {
        $options[] = htmlspecialchars($protocol . ' ('. $matchArr[2] .')', ENT_QUOTES);
      } else {
        $options[] = htmlspecialchars($protocol, ENT_QUOTES);
      }
    }
  }

  if (count($options) === 0) {
    // This could also be WEP but wpa_supplicant doesn't have a way to determine
    // this.
    // And you shouldn't be using WEP these days anyway.
    return 'Open';
  } else {
    return implode('<br />', $options);
  }
}

/**
*
*
*/
function DisplayOpenVPNConfig() {

	exec( 'cat '. RASPI_OPENVPN_CLIENT_CONFIG, $returnClient );
	exec( 'cat '. RASPI_OPENVPN_SERVER_CONFIG, $returnServer );
	exec( 'pidof openvpn | wc -l', $openvpnstatus);

	if( $openvpnstatus[0] == 0 ) {
		$status = '<div class="alert alert-warning alert-dismissable">OpenVPN is not running
					<button type="button" class="close" data-dismiss="alert" aria-hidden="true">×</button></div>';
	} else {
		$status = '<div class="alert alert-success alert-dismissable">OpenVPN is running
					<button type="button" class="close" data-dismiss="alert" aria-hidden="true">×</button></div>';
	}

	// parse client settings
	foreach( $returnClient as $a ) {
		if( $a[0] != "#" ) {
			$arrLine = explode( " ",$a) ;
			$arrClientConfig[$arrLine[0]]=$arrLine[1];
		}
	}

	// parse server settings
	foreach( $returnServer as $a ) {
		if( $a[0] != "#" ) {
			$arrLine = explode( " ",$a) ;
			$arrServerConfig[$arrLine[0]]=$arrLine[1];
		}
	}
	?>
	<div class="row">
	<div class="col-lg-12">
		<div class="panel panel-primary">
			<div class="panel-heading"><i class="fa fa-lock fa-fw"></i> Configure OpenVPN </div>
		<!-- /.panel-heading -->
		<div class="panel-body">
			<!-- Nav tabs -->
			<ul class="nav nav-tabs">
				<li class="active"><a href="#openvpnclient" data-toggle="tab">Client settings</a></li>
				<li><a href="#openvpnserver" data-toggle="tab">Server settings</a></li>
			</ul>
			<!-- Tab panes -->
			<div class="tab-content">
				<p><?php echo $status; ?></p>
				<div class="tab-pane fade in active" id="openvpnclient">

					<h4>Client settings</h4>
					<form role="form" action="?page=save_hostapd_conf" method="POST">

					<div class="row">
						<div class="form-group col-md-4">
							<label>Select OpenVPN configuration file (.ovpn)</label>
							<input type="file" name="openvpn-config">
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">Client Log</label>
							<input type="text" class="form-control" id="disabledInput" name="log-append" type="text" placeholder="<?php echo htmlspecialchars($arrClientConfig['log-append'], ENT_QUOTES); ?>" disabled="disabled" />
						</div>
					</div>
				</div>
				<div class="tab-pane fade" id="openvpnserver">
					<h4>Server settings</h4>
					<div class="row">
						<div class="form-group col-md-4">
						<label for="code">Port</label> 
						<input type="text" class="form-control" name="openvpn_port" value="<?php echo htmlspecialchars($arrServerConfig['port'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
						<label for="code">Protocol</label>
						<input type="text" class="form-control" name="openvpn_proto" value="<?php echo htmlspecialchars($arrServerConfig['proto'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
						<label for="code">Root CA certificate</label>
						<input type="text" class="form-control" name="openvpn_rootca" placeholder="<?php echo htmlspecialchars($arrServerConfig['ca'], ENT_QUOTES); ?>" disabled="disabled" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
						<label for="code">Server certificate</label>
						<input type="text" class="form-control" name="openvpn_cert" placeholder="<?php echo htmlspecialchars($arrServerConfig['cert'], ENT_QUOTES); ?>" disabled="disabled" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
						<label for="code">Diffie Hellman parameters</label>
						<input type="text" class="form-control" name="openvpn_dh" placeholder="<?php echo htmlspecialchars($arrServerConfig['dh'], ENT_QUOTES); ?>" disabled="disabled" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
						<label for="code">KeepAlive</label>
						<input type="text" class="form-control" name="openvpn_keepalive" value="<?php echo htmlspecialchars($arrServerConfig['keepalive'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
						<label for="code">Server log</label>
						<input type="text" class="form-control" name="openvpn_status" placeholder="<?php echo htmlspecialchars($arrServerConfig['status'], ENT_QUOTES); ?>" disabled="disabled" />
						</div>
					</div>
				</div>
				<input type="submit" class="btn btn-outline btn-primary" name="SaveOpenVPNSettings" value="Save settings" />
				<?php
				if($hostapdstatus[0] == 0) {
					echo '<input type="submit" class="btn btn-success" name="StartOpenVPN" value="Start OpenVPN" />' , PHP_EOL;
				} else {
					echo '<input type="submit" class="btn btn-warning" name="StopOpenVPN" value="Stop OpenVPN" />' , PHP_EOL;
				}
?>
				</form>
		</div><!-- /.panel-body -->
	</div><!-- /.panel-primary -->
	<div class="panel-footer"> Information provided by openvpn</div>
</div><!-- /.col-lg-12 -->
</div><!-- /.row -->
<?php
}

/**
*
*
*/
function DisplayTorProxyConfig(){

	exec( 'cat '. RASPI_TORPROXY_CONFIG, $return );
	exec( 'pidof tor | wc -l', $torproxystatus);

	if( $torproxystatus[0] == 0 ) {
		$status = '<div class="alert alert-warning alert-dismissable">TOR is not running
					<button type="button" class="close" data-dismiss="alert" aria-hidden="true">×</button></div>';
	} else {
		$status = '<div class="alert alert-success alert-dismissable">TOR is running
					<button type="button" class="close" data-dismiss="alert" aria-hidden="true">×</button></div>';
	}

	$arrConfig = array();
	foreach( $return as $a ) {
		if( $a[0] != "#" ) {
			$arrLine = explode( " ",$a) ;
			$arrConfig[$arrLine[0]]=$arrLine[1];
		}
	}

?>
	<div class="row">
	<div class="col-lg-12">
		<div class="panel panel-primary">
			<div class="panel-heading"><i class="fa fa-eye-slash fa-fw"></i> Configure TOR proxy</div>
        <!-- /.panel-heading -->
        <div class="panel-body">
        	<!-- Nav tabs -->
            <ul class="nav nav-tabs">
                <li class="active"><a href="#basic" data-toggle="tab">Basic</a>
                </li>
                <li><a href="#relay" data-toggle="tab">Relay</a>
                </li>
            </ul>

            <!-- Tab panes -->
           	<div class="tab-content">
           		<p><?php echo $status; ?></p>

            	<div class="tab-pane fade in active" id="basic">
            		<h4>Basic settings</h4>
					<form role="form" action="?page=save_hostapd_conf" method="POST">
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">VirtualAddrNetwork</label>
							<input type="text" class="form-control" name="virtualaddrnetwork" value="<?php echo htmlspecialchars($arrConfig['VirtualAddrNetwork'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">AutomapHostsSuffixes</label>
							<input type="text" class="form-control" name="automaphostssuffixes" value="<?php echo htmlspecialchars($arrConfig['AutomapHostsSuffixes'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">AutomapHostsOnResolve</label>
							<input type="text" class="form-control" name="automaphostsonresolve" value="<?php echo htmlspecialchars($arrConfig['AutomapHostsOnResolve'], ENT_QUOTES); ?>" />
						</div>
					</div>	
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">TransListenAddress</label>
							<input type="text" class="form-control" name="translistenaddress" value="<?php echo htmlspecialchars($arrConfig['TransListenAddress'], ENT_QUOTES); ?>" />
						</div>
					</div>	
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">DNSPort</label>
							<input type="text" class="form-control" name="dnsport" value="<?php echo htmlspecialchars($arrConfig['DNSPort'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">DNSListenAddress</label>
							<input type="text" class="form-control" name="dnslistenaddress" value="<?php echo htmlspecialchars($arrConfig['DNSListenAddress'], ENT_QUOTES); ?>" />
						</div>
					</div>
				</div>
				<div class="tab-pane fade" id="relay">
            		<h4>Relay settings</h4>
            		<div class="row">
						<div class="form-group col-md-4">
							<label for="code">ORPort</label>
							<input type="text" class="form-control" name="orport" value="<?php echo htmlspecialchars($arrConfig['ORPort'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">ORListenAddress</label>
							<input type="text" class="form-control" name="orlistenaddress" value="<?php echo htmlspecialchars($arrConfig['ORListenAddress'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">Nickname</label>
							<input type="text" class="form-control" name="nickname" value="<?php echo htmlspecialchars($arrConfig['Nickname'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">Address</label>
							<input type="text" class="form-control" name="address" value="<?php echo htmlspecialchars($arrConfig['Address'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">RelayBandwidthRate</label>
							<input type="text" class="form-control" name="relaybandwidthrate" value="<?php echo htmlspecialchars($arrConfig['RelayBandwidthRate'], ENT_QUOTES); ?>" />
						</div>
					</div>
					<div class="row">
						<div class="form-group col-md-4">
							<label for="code">RelayBandwidthBurst</label>
							<input type="text" class="form-control" name="relaybandwidthburst" value="<?php echo htmlspecialchars($arrConfig['RelayBandwidthBurst'], ENT_QUOTES); ?>" />
						</div>
					</div>
				</div>

				<input type="submit" class="btn btn-outline btn-primary" name="SaveTORProxySettings" value="Save settings" />
				<?php 
				if( $torproxystatus[0] == 0 ) {
					echo '<input type="submit" class="btn btn-success" name="StartTOR" value="Start TOR" />' , PHP_EOL;
				} else {
					echo '<input type="submit" class="btn btn-warning" name="StopTOR" value="Stop TOR" />' , PHP_EOL;
				};
				?>
				</form>
			</div><!-- /.tab-content -->
		</div><!-- /.panel-body -->
		<div class="panel-footer"> Information provided by tor</div>
    </div><!-- /.panel-primary -->
</div><!-- /.col-lg-12 -->
</div><!-- /.row -->
<?php 
}

/**
*
*
*/
function SaveTORAndVPNConfig(){
  if( isset($_POST['SaveOpenVPNSettings']) ) {
    // TODO
  } elseif( isset($_POST['SaveTORProxySettings']) ) {
    // TODO
  } elseif( isset($_POST['StartOpenVPN']) ) {
    echo "Attempting to start openvpn";
    exec( 'sudo /etc/init.d/openvpn start', $return );
    foreach( $return as $line ) {
      echo htmlspecialchars($line, ENT_QUOTES).'<br />' , PHP_EOL;
    }
  } elseif( isset($_POST['StopOpenVPN']) ) {
    echo "Attempting to stop openvpn";
    exec( 'sudo /etc/init.d/openvpn stop', $return );
    foreach( $return as $line ) {
      echo htmlspecialchars($line, ENT_QUOTES).'<br />' , PHP_EOL;
    }
  } elseif( isset($_POST['StartTOR']) ) {
    echo "Attempting to start TOR";
    exec( 'sudo /etc/init.d/tor start', $return );
    foreach( $return as $line ) {
      echo htmlspecialchars($line, ENT_QUOTES).'<br />' , PHP_EOL;
    }
  } elseif( isset($_POST['StopTOR']) ) {
    echo "Attempting to stop TOR";
    exec( 'sudo /etc/init.d/tor stop', $return );
    foreach( $return as $line ) {
      echo htmlspecialchars($line, ENT_QUOTES).'<br />' , PHP_EOL;
    }
  }
}