// pfSense gateway monitoring and static routes changer script :)
//
$script_version = "0.17a (2019-06-12)";
//
// based on status_gateway.php and system_routes.php from pfSense 2.0
// Written by: Tomas Lajbl
// 
// If you want to run this script, use the following syntax (without quotes) 
// on pfSense command line:
// "pfSsh.php playback <script file name>"
// 
// For the first run, create file test.error in /etc/phpshellsessions directory.
// It will be set to correct filename on the script first run.
//

$date = date('Y-m-d H:i:s'); // Script starts at date & time

// Set the correct gateway names here. :)

$gw0 = TUN1_VPNV4;  // main gateway
$gw1 = TUN3_VPNV4;  // backup gateway

// Read all system gateways.

$a_gateways = return_gateways_array();
$gateways_status = return_gateways_status(true);

// Read all static routes from config.xml. 

$a_routes = &$config['staticroutes']['route'];
$a_gateways_long = return_gateways_array(true, true, true);
$a_routed_networks = array();

foreach ($a_routes as $i => $route) {

  // If static route is disabled, skip it.
	if (isset($route['disabled'])) {
		
	}
  
  else {
  
    // Read the gateway name for this route.
    $gw_name = ($a_gateways_long[$route['gateway']]['name']);
    
    // If is the main gateway set above, put the routed network to an network array.
    if ($gw_name == $gw0) {
    
      $a_routed_networks[] = strtolower($route['network']);
    
    }
    
    else {    
    }
    		
	}

}


// Gateways monitoring start

echo "=============================================\n";
echo "Gateway monitoring script ".$script_version."\n";
echo " ".$date."\n";
echo "=============================================\n";

foreach ($a_gateways as $i => $gateway) {

      // Main gateway
      
      if ($gateways_status[$i]['name'] == $gw0) {
            
         // IP address detection
         $gw0_ip = lookup_gateway_ip_by_name($i);  // 
                  
         // Main gateway status
            
         if ($gateways_status[$i]['status'] == "down") {
         
            $gw0_status = "down";
            $gw0_status_echo = "DOWN";
         
            }
         
         elseif ($gateways_status[$i]['status'] == "force_down") {
         
            $gw0_status = "down";
            $gw0_status_echo = "FORCED DOWN";

            }
         
         elseif ($gateways_status[$i]['status'] == "none")  {
         
            $gw0_status = "up";
            $gw0_status_echo = "UP";
         
            }
         
         else {
         
            // You can define another gateway status action here (packet loss, high latency etc.)
         
            } 
       }         


      // Backup gateway
               
      if ($gateways_status[$i]['name'] == $gw1) {
      
         // IP address detection
         $gw1_ip = lookup_gateway_ip_by_name($i);
         
         // Backup gateway status
           
         if ($gateways_status[$i]['status'] == "down") {
         
            $gw1_status = "down";
            $gw1_status_echo = "DOWN";
         
         }
         
         elseif ($gateways_status[$i]['status'] == "force_down") {
         
            $gw1_status = "down";
            $gw1_status_echo = "FORCED DOWN";

         }
         
         elseif ($gateways_status[$i]['status'] == "none")  {
         
            $gw1_status = "up";
            $gw1_status_echo = "UP";
         
         }
         
         else {
         
         // You can define another gateway status action here (packet loss, high latency etc.)
         
         } 
         
      }
    
}


// if OpenVPN client is down, the gateway IP address is "dynamic". In this case, 
// set the gateway status to "down".

if ($gw0_ip == "dynamic") {

   $gw0_status = "down";
  
}

else {
}

if ($gw1_ip == "dynamic") {

   $gw1_status = "down";
  
}

else {
}    


// Display status of gateways

echo "  Main gateway name set:   ".$gw0." (".$gw0_status.")\n";
echo "  Main gateway IP address: ".$gw0_ip."\n";
echo "\n";
echo "Backup gateway name set:   ".$gw1." (".$gw1_status.")\n";
echo "Backup gateway IP address: ".$gw1_ip."\n";
echo "\n";


// Set action

if (($gw0_status == "up") AND ($gw1_status == "up")) {

   $active_gateway = "both";
   echo "On ".$active_gateway."\n";

   }
   
elseif (($gw0_status == "up") AND ($gw1_status == "down")) {   

   $active_gateway = "main";
   echo "On ".$active_gateway."\n";

   }

elseif (($gw0_status == "down") AND ($gw1_status == "up")) {   

   $active_gateway = "backup";
   echo "On ".$active_gateway."\n";

   }

elseif (($gw0_status == "down") AND ($gw1_status == "down")) {   

   $active_gateway = "none";
   echo "Both gateways down.\n";

   }

else {
}


// Check the previous gateway state

// Both gateways were active.

$last_status_file = '/etc/phpshellsessions/test.onboth';

if (file_exists($last_status_file)) {

    // echo "The file $last_status_file exists.\n";
    $gw_status_last = "both";
    
} else {

}

// Main gateway ONLY was active.

$last_status_file = '/etc/phpshellsessions/test.onmain';

if (file_exists($last_status_file)) {

    // echo "The file $last_status_file exists.\n";
    $gw_status_last = "main";
    
} else {

}

// Backup gateway ONLY was active.

$last_status_file = '/etc/phpshellsessions/test.onbackup';

if (file_exists($last_status_file)) {

    // echo "The file $last_status_file exists.\n";
    $gw_status_last = "backup";
    
} else {

}

// Both gateways were down.

$last_status_file = '/etc/phpshellsessions/test.error';

if (file_exists($last_status_file)) {

    // echo "The file $last_status_file exists.\n";
    $gw_status_last = "error";
    
} else {

}



// Change routes to another gateway if needed.
// We have to test many possible combinations.   

// 1) Main gateway was UP, now is UP. Backup gateway was UP, now is UP. Nothing to do.

if (($gw_status_last == "both") AND ($active_gateway == "both")) {

   echo "Main gateway was UP, now is ".$gw0_status_echo.". Backup gateway was UP, now is ".$gw1_status_echo.". Nothing to do.\n";
   echo "\n";
   
   // rename("/etc/phpshellsessions/test.onboth", "/etc/phpshellsessions/test.onboth");
  
}


// 2) Main gateway was UP, now is UP. Backup gateway is DOWN. Display warning.

elseif (($gw_status_last == "both") AND ($active_gateway == "main")) {

   echo "Main gateway was UP, now is ".$gw0_status_echo.".\n";
   echo "WARNING!!! Backup gateway is ".$gw1_status_echo.". We have no backup gateway!\n";
   echo "\n";
   
   rename("/etc/phpshellsessions/test.onboth", "/etc/phpshellsessions/test.onmain");
   
}


// 3) Main gateway was UP, now is UP. Backup gateway was DOWN, now is UP. Nothing to do.

elseif (($gw_status_last == "main") AND ($active_gateway == "both")) {

   echo "Main gateway was UP, now is ".$gw0_status_echo.". Backup gateway was DOWN, now is ".$gw1_status_echo.". Nothing to do.\n";
   echo "\n";
   
   rename("/etc/phpshellsessions/test.onmain", "/etc/phpshellsessions/test.onboth");
   
}


// 4) Main gateway was UP, now is UP. Backup gateway was DOWN, is still DOWN.

elseif (($gw_status_last == "main") AND ($active_gateway == "main")) {

   echo "Main gateway was UP, now is ".$gw0_status_echo.".\n";
   echo "WARNING!!! Backup gateway is still ".$gw1_status_echo.". We have no backup gateway!\n";
   echo "\n";

   // rename("/etc/phpshellsessions/test.onmain", "/etc/phpshellsessions/test.onmain");
   
}


// 5) Main gateway is DOWN, so check the backup gateway status.

elseif ($active_gateway == "backup") {

   // Main gateway is DOWN, backup gateway is UP. Switch to backup.

   if ($gw1_status == "up") {

     echo "WARNING!!! Main gateway is ".$gw0_status_echo.". Backup gateway is ".$gw1_status_echo.".\n";
     echo "We set routes via backup gateway.\n";
     echo "\n";
   
     rename("/etc/phpshellsessions/test.onboth", "/etc/phpshellsessions/test.onbackup");  
     echo "We change these routes:\n";
   
     foreach ($a_routed_networks as $i => $routed_network) {
 
       $route_command = "route change -net " . $routed_network . " " . $gw1_ip;
       echo $route_command . "\n";
       exec($route_command);

       }

     }
     
   }


// 6) Main gateway was DOWN, now is UP. Backup gateway was/is UP. Change routes back to main.

elseif (($gw_status_last == "backup") AND ($active_gateway == "both")) {

   echo "Main gateway was DOWN, now is ".$gw0_status_echo." again. We changed routes back to main.\n";
   echo "\n";
   
   rename("/etc/phpshellsessions/test.onbackup", "/etc/phpshellsessions/test.onboth");   
   echo "We change these routes:\n";
   
     foreach ($a_routed_networks as $i => $routed_network) {
 
       $route_command = "route change -net " . $routed_network . " " . $gw0_ip;
       echo $route_command . "\n";
       exec($route_command);

     }

}


// 7) Both gateways were DOWN, both gateways are UP now. Change routes back to main.

elseif (($gw_status_last == "error") AND ($active_gateway == "both")) {

   echo "Both gateways were DOWN. Main gateway is ".$gw0_status_echo." now. Backup gateway is ".$gw1_status_echo." now. We changed routes back to main.\n";
   echo "\n";
   
   rename("/etc/phpshellsessions/test.error", "/etc/phpshellsessions/test.onboth");   
   echo "We change these routes:\n";
   
     foreach ($a_routed_networks as $i => $routed_network) {
 
       $route_command = "route change -net " . $routed_network . " " . $gw0_ip;
       echo $route_command . "\n";
       exec($route_command);

     }

}


// 8) Both gateways were DOWN, only main gateway is now UP.

elseif (($gw_status_last == "error") AND ($active_gateway == "main")) {

   echo "Both gateways was DOWN. ONLY MAIN gateway is ".$gw0_status_echo." now. We changed routes back to main.\n";
   echo "\n";
   
   rename("/etc/phpshellsessions/test.error", "/etc/phpshellsessions/test.onmain");   
   echo "We change these routes:\n";
   
   foreach ($a_routed_networks as $i => $routed_network) {
 
     $route_command = "route change -net " . $routed_network . " " . $gw0_ip;
     echo $route_command . "\n";
     exec($route_command);

   }

}


// 9) Both gateways were DOWN, only backup gateway is now UP.

elseif (($gw_status_last == "error") AND ($active_gateway == "backup")) {

   echo "Both gateways was DOWN. ONLY BACKUP gateway is ".$gw0_status_echo." now. We changed routes to backup.\n";
   echo "\n";
   
   rename("/etc/phpshellsessions/test.error", "/etc/phpshellsessions/test.onbackup");  
   echo "We change these routes:\n";
   
   foreach ($a_routed_networks as $i => $routed_network) {
 
     $route_command = "route change -net " . $routed_network . " " . $gw1_ip;
     echo $route_command . "\n";
     exec($route_command);

   }

}


// 10) Both gateways are DOWN. General failure. :(

elseif ($active_gateway == "none") {

   echo "WARNING!!! We have both gateways down! Check your hardware.\n";

   if (file_exists("/etc/phpshellsessions/test.onboth")) {   
      rename("/etc/phpshellsessions/test.onboth", "/etc/phpshellsessions/test.error");
      }
   elseif (file_exists("/etc/phpshellsessions/test.onmain")) {
      rename("/etc/phpshellsessions/test.onmain", "/etc/phpshellsessions/test.error");
      }   
   elseif (file_exists("/etc/phpshellsessions/test.onbackup")) {
      rename("/etc/phpshellsessions/test.onbackup", "/etc/phpshellsessions/test.error");
      }
   else {
      // File test.error already exists, so both gateways WERE DOWN previously; nothing to do.
      }
      

}


// Display output to pfSense console, write some log.
// I'am newbie in PHP. So if you are an advanced PHP programmer, write some code here. :)


// End of script