<?php

require_once 'includes/status_messages.php';
require_once 'includes/functions.php';

define('RASPAP_IPTABLES_SCRIPT',"/tmp/iptables_raspap.sh");
define('RASPAP_IP6TABLES_SCRIPT',"/tmp/ip6tables_raspap.sh");

function getDependson(&$rule, &$conf) {
   if ( isset($rule["dependson"][0]) ) {
      $don = &$rule["dependson"];
      if ( !empty($don[0]) && isset($conf[$don[0]["var"]]) ) {
         if ( !isset($don[0]["type"]) ) $don[0]["type"]="bool";
         return $don;
      }
   }
   return false;
}

function isRuleEnabled(&$sect, &$conf) {
   $fw_on = isset($conf["firewall-enable"]) && $conf["firewall-enable"];
   $active = isset($sect["fw-state"]) && $sect["fw-state"]==1;
   $active = $fw_on ? $active : !$active;
   $active = $active || !isset($sect["fw-state"]);
   if ( ($don = getDependson($sect, $conf)) !== false &&
         $don[0]["type"] == "bool" && !$conf[$don[0]["var"]] )  $active = false;
   return $active;
}

function createRuleStr(&$sect, &$conf) {
   if ( !is_array($sect["rules"]) ) return "";
   $rules = $sect["rules"];
   $depon = getDependson($sect,$conf);
   $rs = array();
   foreach ( $rules as $rule ) {
      if ( preg_match('/\$[a-z0-9]*\$/i',$rule) ) {
         $r = array($rule);
         foreach ( $depon as $dep ) {
            $rr = array();
            $repl=$val="";
            switch ( $dep["type"] ) {
               case "list":
                   if ( isset($dep["var"]) && !empty($conf[$dep["var"]]) ) $val = explode(' ', $conf[$dep["var"]]);
                   if ( !empty($val) && isset($dep["replace"]) ) $repl=$dep["replace"];
                   break;
               case "string":
                   if ( isset($dep["var"]) ) $val=$conf[$dep["var"]];
                   if ( !empty($val) && isset($dep["replace"]) ) $repl=$dep["replace"];
                   break;
               default:
                   break;
            }
            if ( !empty($repl) && !empty($val) ) {
               if ( is_array($val) ) {
                  foreach ( $val as $v ) $rr = array_merge($rr,str_replace($repl, $v, $r));
               }
               else $rr = array_merge($rr, str_replace($repl, $val, $r));
            }
            $r = !empty($rr) ? $rr : $r;
         }
         $rs = array_merge($rs,$rr);
      } else {
         $rs[] = $rule;
      }
   }
   $str="";
   foreach ( $rs as $r ) {
      if ( !preg_match('/\$[a-z0-9]*\$/i',$r) ) $str .= '$IPT '.$r."\n";
   }
   return $str;
}

function isIPv4(&$rule) {
    return !isset($rule["ip-version"]) || strstr($rule["ip-version"],"4") !== false; 
}

function isIPv6(&$rule) {
    return !isset($rule["ip-version"]) || strstr($rule["ip-version"],"6") !== false; 
}

function configureFirewall() {
    $json = file_get_contents(RASPAP_IPTABLES_CONF);
    $ipt  = json_decode($json, true);
    $conf = ReadFirewallConf();
    $txt = "#!/bin/bash\n";
    file_put_contents(RASPAP_IPTABLES_SCRIPT, $txt);
    file_put_contents(RASPAP_IP6TABLES_SCRIPT, $txt);
    file_put_contents(RASPAP_IPTABLES_SCRIPT, 'IPT="iptables"'."\n", FILE_APPEND);
    file_put_contents(RASPAP_IP6TABLES_SCRIPT, 'IPT="ip6tables"'."\n", FILE_APPEND);
    $txt = "\$IPT -F\n";
    $txt .= "\$IPT -X\n";
    $txt .= "\$IPT -t nat -F\n";
    file_put_contents(RASPAP_IPTABLES_SCRIPT, $txt, FILE_APPEND);
    file_put_contents(RASPAP_IP6TABLES_SCRIPT, $txt, FILE_APPEND);
    if ( empty($conf) || empty($ipt) ) return false;
    $count=0;
    foreach ( $ipt["order"] as $idx ) {
       if ( isset($ipt[$idx]) ) {
          foreach ( $ipt[$idx] as $i => $sect ) {
             if ( isRuleEnabled($sect, $conf) ) {
               $str_rules= createRuleStr($sect, $conf);
               if ( !empty($str_rules) ) {
                  if ( isIPv4($sect) ) file_put_contents(RASPAP_IPTABLES_SCRIPT, $str_rules, FILE_APPEND);
                  if ( isIPv6($sect) ) file_put_contents(RASPAP_IP6TABLES_SCRIPT, $str_rules, FILE_APPEND);
                  ++$count;
               }
             }
          }
       }
    }
    if ( $count > 0 ) {
       exec("chmod +x ".RASPAP_IPTABLES_SCRIPT);
       exec("sudo ".RASPAP_IPTABLES_SCRIPT);
//       exec("sudo iptables-save > /etc/iptables/rules.v4");
//       unlink(RASPAP_IPTABLES_SCRIPT);
       exec("chmod +x ".RASPAP_IP6TABLES_SCRIPT);
       exec("sudo ".RASPAP_IP6TABLES_SCRIPT);
//       exec("sudo iptables-save > /etc/iptables/rules.v6");
//       unlink(RASPAP_IP6TABLES_SCRIPT);
    }
    return ($count > 0);
}

function WriteFirewallConf($conf) {
    $ret = false;
        if ( is_array($conf) ) write_php_ini($conf,RASPAP_FIREWALL_CONF);
    return $ret;
}


function ReadFirewallConf() {
    if ( file_exists(RASPAP_FIREWALL_CONF) ) {
       $conf = parse_ini_file(RASPAP_FIREWALL_CONF);
    } else {
       $conf = array();
       $conf["firewall-enable"] = false;
       $conf["ssh-enable"] = false;
       $conf["http-enable"] = false;
       $conf["excl-devices"] = "";
       $conf["excluded-ips"] = "";
       $conf["ap-device"] = "";
       $conf["client-device"] = "";
       $conf["restricted-ips"] = "";
    }
    return $conf;
}

function getVPN_IPs() {
    $ips = "";
    # get openvpn server IPs for UDP (if existing)
    if ( RASPI_OPENVPN_ENABLED && ($fconf = glob(RASPI_OPENVPN_CLIENT_PATH ."/*.conf")) !== false && !empty($fconf) ) {
      foreach ( $fconf as $f ) {
         unset($result);
         exec('cat '.$f.' |  sed -rn "s/^remote\s*([a-z0-9\.\-\_]*)\s*([0-9]*).*$/\1/ip" ', $result);
         $ip = (isset($result[0])) ? $result[0] : "";
         unset($result);
         exec('cat '.$f.' |  sed -rn "s/^proto\s*([a-z]*).*$/\1/ip" ', $result);
         $proto = (isset($result[0])) ? $result[0] : "";
         if ( !empty($ip) && trim(strtolower($proto)) === "udp" ) {
            $ip = gethostbyname($ip);
            if ( filter_var($ip,FILTER_VALIDATE_IP) && strpos($ips, $ip) === false ) $ips .= " $ip";
        }
      }
    }
    # get wireguard server IPs for UDP (if existing)
    if ( RASPI_WIREGUARD_ENABLED && ($fconf = glob(RASPI_WIREGUARD_PATH ."/*.conf")) !== false && !empty($fconf) ) {
    }
    return trim($ips);
}


function DisplayFirewallConfig()
{

    $status = new StatusMessages();

    $json = file_get_contents(RASPAP_IPTABLES_CONF);
    $ipt_rules = json_decode($json, true);
    getWifiInterface();
    $ap_device = $_SESSION['ap_interface'];
    $clients = getClients();
    $str_clients = "";
    foreach( $clients["device"] as $dev ) {
       if ( !$dev["isAP"] ) {
          if ( !empty($str_clients) ) $str_clients .= ", ";
          $str_clients .= $dev["name"];
       }
    }
    $fw_conf = ReadFirewallConf();
    $fw_conf["ap-device"] = $ap_device;
    $id=findCurrentClientIndex($clients);
    if ( $id >= 0 ) $fw_conf["client-device"] = $clients["device"][$id]["name"];
    if (!empty($_POST)) {
        $fw_conf["ssh-enable"] = isset($_POST['ssh-enable']);
        $fw_conf["http-enable"] = isset($_POST['http-enable']);
        $fw_conf["firewall-enable"] = isset($_POST['firewall-enable']) || isset($_POST['apply-firewall']);
        if ( isset($_POST['firewall-enable']) ) $status->addMessage(_('Firewall is now enabled'), 'success');
        if ( isset($_POST['apply-firewall']) )  $status->addMessage(_('Firewall settings changed'), 'success');
        if ( isset($_POST['firewall-disable']) ) $status->addMessage(_('Firewall is now disabled'), 'warning');
        if ( isset($_POST['save-firewall']) )  $status->addMessage(_('Firewall settings saved. Firewall is still disabled.'), 'success');
        if ( isset($_POST['excl-devices'])  ) {
           $excl = filter_var($_POST['excl-devices'], FILTER_SANITIZE_STRING);
           $excl = str_replace(',', ' ', $excl);
           $excl = trim(preg_replace('/\s+/', ' ', $excl));
           if ( $fw_conf["excl-devices"] != $excl ) {
               $status->addMessage(_('Exclude devices '. $excl), 'success');
               $fw_conf["excl-devices"] = $excl;
           }
        }
        if ( isset($_POST['excluded-ips'])  ) {
           $excl = filter_var($_POST['excluded-ips'], FILTER_SANITIZE_STRING);
           $excl = str_replace(',', ' ', $excl);
           $excl = trim(preg_replace('/\s+/', ' ', $excl));
           if ( !empty($excl) ) {
              $excl = explode(' ',$excl);
              $str_excl = "";
              foreach ( $excl as $ip ) {
                 if ( filter_var($ip,FILTER_VALIDATE_IP) ) $str_excl .= "$ip ";
                 else $status->addMessage(_('Exclude IP address '. $ip . ' failed - not a valid IP address'), 'warning');
              }
          }
          $str_excl = trim($str_excl);
          if ( $fw_conf["excluded-ips"] != $str_excl ) {
               $status->addMessage(_('Exclude IP address(es) '. $str_excl ), 'success');
               $fw_conf["excluded-ips"] = $str_excl;
           }
        }
        WriteFirewallConf($fw_conf);
        configureFirewall();
    }
    $vpn_ips = getVPN_IPs();
    echo renderTemplate("firewall", compact(
                "status",
                "ap_device",
                "str_clients",
                "fw_conf",
                "ipt_rules",
                "vpn_ips")
    );
}