<?php
/* Pi-hole: A black hole for Internet advertisements
*  (c) 2017 Pi-hole, LLC (https://pi-hole.net)
*  Network-wide ad blocking via your own hardware.
*
*  This file is copyright under the latest version of the EUPL.
*  Please see LICENSE file for your rights under this license.
*/

require_once 'func.php';

if (!in_array(basename($_SERVER['SCRIPT_FILENAME']), array('settings.php', 'teleporter.php'), true)) {
    exit('Direct access to this script is forbidden!');
}

// Check for existence of variable
// and test it only if it exists
function istrue(&$argument)
{
    if (isset($argument)) {
        if ($argument) {
            return true;
        }
    }

    return false;
}

function formatMAC($mac_addr)
{
    preg_match('/([0-9a-fA-F]{2}[:]){5}([0-9a-fA-F]{2})/', $mac_addr, $matches);
    if (count($matches) > 0) {
        return $matches[0];
    }

    return null;
}

$dhcp_static_leases = array();
function readStaticLeasesFile($origin_file = '/etc/dnsmasq.d/04-pihole-static-dhcp.conf')
{
    global $dhcp_static_leases;
    $dhcp_static_leases = array();
    if (!file_exists($origin_file) || !is_readable($origin_file)) {
        return false;
    }

    $dhcpstatic = @fopen($origin_file, 'r');
    if (!is_resource($dhcpstatic)) {
        return false;
    }

    while (!feof($dhcpstatic)) {
        // Remove any possibly existing variable with this name
        $mac = '';
        $one = '';
        $two = '';
        sscanf(trim(fgets($dhcpstatic)), 'dhcp-host=%[^,],%[^,],%[^,]', $mac, $one, $two);
        if (strlen($mac) > 0 && validMAC($mac)) {
            if (validIP($one) && strlen($two) == 0) {
                // dhcp-host=mac,IP - no HOST
                array_push($dhcp_static_leases, array('hwaddr' => $mac, 'IP' => $one, 'host' => ''));
            } elseif (strlen($two) == 0) {
                // dhcp-host=mac,hostname - no IP
                array_push($dhcp_static_leases, array('hwaddr' => $mac, 'IP' => '', 'host' => $one));
            } else {
                // dhcp-host=mac,IP,hostname
                array_push($dhcp_static_leases, array('hwaddr' => $mac, 'IP' => $one, 'host' => $two));
            }
        } elseif (validIP($one) && validDomain($mac)) {
            // dhcp-host=hostname,IP - no MAC
            array_push($dhcp_static_leases, array('hwaddr' => '', 'IP' => $one, 'host' => $mac));
        }
    }

    return true;
}

function isequal(&$argument, &$compareto)
{
    if (isset($argument)) {
        if ($argument === $compareto) {
            return true;
        }
    }

    return false;
}

function isinserverlist($addr)
{
    global $DNSserverslist;
    foreach ($DNSserverslist as $key => $value) {
        if (isequal($value['v4_1'], $addr) || isequal($value['v4_2'], $addr)) {
            return true;
        }
        if (isequal($value['v6_1'], $addr) || isequal($value['v6_2'], $addr)) {
            return true;
        }
    }

    return false;
}

$DNSserverslist = array();
function readDNSserversList()
{
    // Reset list
    $list = array();
    $handle = @fopen('/etc/pihole/dns-servers.conf', 'r');
    if ($handle) {
        while (($line = fgets($handle)) !== false) {
            $line = rtrim($line);
            $line = explode(';', $line);
            $name = $line[0];
            $values = array();
            if (!empty($line[1]) && validIP($line[1])) {
                $values['v4_1'] = $line[1];
            }
            if (!empty($line[2]) && validIP($line[2])) {
                $values['v4_2'] = $line[2];
            }
            if (!empty($line[3]) && validIP($line[3])) {
                $values['v6_1'] = $line[3];
            }
            if (!empty($line[4]) && validIP($line[4])) {
                $values['v6_2'] = $line[4];
            }
            $list[$name] = $values;
        }
        fclose($handle);
    }

    return $list;
}

require_once 'database.php';

function addStaticDHCPLease($mac, $ip, $hostname)
{
    global $error, $success, $dhcp_static_leases;

    try {
        if (!validMAC($mac)) {
            throw new Exception('MAC address ('.htmlspecialchars($mac).') is invalid!<br>', 0);
        }
        $mac = strtoupper($mac);

        if (!validIP($ip) && strlen($ip) > 0) {
            throw new Exception('IP address ('.htmlspecialchars($ip).') is invalid!<br>', 1);
        }

        if (!validDomain($hostname) && strlen($hostname) > 0) {
            throw new Exception('Host name ('.htmlspecialchars($hostname).') is invalid!<br>', 2);
        }

        if (strlen($hostname) == 0 && strlen($ip) == 0) {
            throw new Exception('You can not omit both the IP address and the host name!<br>', 3);
        }

        if (strlen($hostname) == 0) {
            $hostname = 'nohost';
        }

        if (strlen($ip) == 0) {
            $ip = 'noip';
        }

        // Test if this lease is already included
        readStaticLeasesFile();

        foreach ($dhcp_static_leases as $lease) {
            if ($lease['hwaddr'] === $mac) {
                throw new Exception('Static lease for MAC address ('.htmlspecialchars($mac).') already defined!<br>', 4);
            }
            if ($ip !== 'noip' && $lease['IP'] === $ip) {
                throw new Exception('Static lease for IP address ('.htmlspecialchars($ip).') already defined!<br>', 5);
            }
            if ($lease['host'] === $hostname) {
                throw new Exception('Static lease for hostname ('.htmlspecialchars($hostname).') already defined!<br>', 6);
            }
        }

        pihole_execute('-a addstaticdhcp '.$mac.' '.$ip.' '.$hostname);
        $success .= 'A new static address has been added';

        return true;
    } catch (Exception $exception) {
        $error .= $exception->getMessage();

        return false;
    }
}

// Read available DNS server list
$DNSserverslist = readDNSserversList();

$error = '';
$success = '';

if (isset($_POST['field'])) {
    // Handle CSRF
    check_csrf(isset($_POST['token']) ? $_POST['token'] : '');

    // Process request
    switch ($_POST['field']) {
        // Set DNS server
        case 'DNS':
            $DNSservers = array();
            // Add selected predefined servers to list
            foreach ($DNSserverslist as $key => $value) {
                foreach (array('v4_1', 'v4_2', 'v6_1', 'v6_2') as $type) {
                    // Skip if this IP type does not
                    // exist (e.g. IPv4-only or only
                    // one IPv6 address upstream
                    // server)
                    if (!array_key_exists($type, $value)) {
                        continue;
                    }

                    // If server exists and is set
                    // (POST), we add it to the
                    // array of DNS servers
                    $server = str_replace('.', '_', $value[$type]);
                    if (array_key_exists('DNSserver'.$server, $_POST)) {
                        array_push($DNSservers, $value[$type]);
                    }
                }
            }

            // Test custom server fields
            for ($i = 1; $i <= 4; ++$i) {
                if (array_key_exists('custom'.$i, $_POST)) {
                    $exploded = explode('#', $_POST['custom'.$i.'val'], 2);
                    $IP = trim($exploded[0]);

                    if (!validIP($IP)) {
                        $error .= 'IP ('.htmlspecialchars($IP).') is invalid!<br>';
                    } else {
                        if (count($exploded) > 1) {
                            $port = trim($exploded[1]);
                            if (!is_numeric($port)) {
                                $error .= 'Port ('.htmlspecialchars($port).') is invalid!<br>';
                            } else {
                                $IP .= '#'.$port;
                            }
                        }

                        array_push($DNSservers, $IP);
                    }
                }
            }
            $DNSservercount = count($DNSservers);

            // Check if at least one DNS server has been added
            if ($DNSservercount < 1) {
                $error .= 'No DNS server has been selected.<br>';
            }

            // Check if domain-needed is requested
            if (isset($_POST['DNSrequiresFQDN'])) {
                $extra = 'domain-needed ';
            } else {
                $extra = 'domain-not-needed ';
            }

            // Check if domain-needed is requested
            if (isset($_POST['DNSbogusPriv'])) {
                $extra .= 'bogus-priv ';
            } else {
                $extra .= 'no-bogus-priv ';
            }

            // Check if DNSSEC is requested
            if (isset($_POST['DNSSEC'])) {
                $extra .= 'dnssec';
            } else {
                $extra .= 'no-dnssec';
            }

            // Check if rev-server is requested
            if (isset($_POST['rev_server'])) {
                // Validate CIDR IP
                $cidr = trim($_POST['rev_server_cidr']);
                if (!validCIDRIP($cidr)) {
                    $error .= 'Conditional forwarding subnet ("'.htmlspecialchars($cidr).'") is invalid!<br>'.
                                'This field requires CIDR notation for local subnets (e.g., 192.168.0.0/16).<br>';
                }

                // Validate target IP
                $target = trim($_POST['rev_server_target']);
                if (!validIP($target)) {
                    $error .= 'Conditional forwarding target IP ("'.htmlspecialchars($target).'") is invalid!<br>';
                }

                // Validate conditional forwarding domain name (empty is okay)
                $domain = trim($_POST['rev_server_domain']);
                if (strlen($domain) > 0 && !validDomain($domain)) {
                    $error .= 'Conditional forwarding domain name ("'.htmlspecialchars($domain).'") is invalid!<br>';
                }

                if (!$error) {
                    $extra .= ' rev-server '.$cidr.' '.$target.' '.$domain;
                }
            }

            // Check if DNSinterface is set
            if (isset($_POST['DNSinterface'])) {
                if ($_POST['DNSinterface'] === 'single') {
                    $DNSinterface = 'single';
                } elseif ($_POST['DNSinterface'] === 'bind') {
                    $DNSinterface = 'bind';
                } elseif ($_POST['DNSinterface'] === 'all') {
                    $DNSinterface = 'all';
                } else {
                    $DNSinterface = 'local';
                }
            } else {
                // Fallback
                $DNSinterface = 'local';
            }
            pihole_execute('-a -i '.$DNSinterface.' -web');

            // Add rate-limiting settings
            if (isset($_POST['rate_limit_count'], $_POST['rate_limit_interval'])) {
                // Restart of FTL is delayed
                pihole_execute('-a ratelimit '.intval($_POST['rate_limit_count']).' '.intval($_POST['rate_limit_interval']).' false');
            }

            // If there has been no error we can save the new DNS server IPs
            if (!strlen($error)) {
                $IPs = implode(',', $DNSservers);
                $return = pihole_execute('-a setdns "'.$IPs.'" '.$extra);
                $success .= htmlspecialchars(end($return)).'<br>';
                $success .= 'The DNS settings have been updated (using '.$DNSservercount.' DNS servers)';
            } else {
                $error .= 'The settings have been reset to their previous values';
            }

            break;
            // Set query logging
        case 'Logging':
            if ($_POST['action'] === 'Disable') {
                pihole_execute('-l off');
                $success .= 'Logging has been disabled and logs have been flushed';
            } elseif ($_POST['action'] === 'Disable-noflush') {
                pihole_execute('-l off noflush');
                $success .= 'Logging has been disabled, your logs have <strong>not</strong> been flushed';
            } else {
                pihole_execute('-l on');
                $success .= 'Logging has been enabled';
            }

            break;
            // Set domains to be excluded from being shown in Top Domains (or Ads) and Top Clients
        case 'API':
            // Explode the contents of the textareas into PHP arrays
            // \n (Unix) and \r\n (Win) will be considered as newline
            // array_filter( ... ) will remove any empty lines
            $domains = array_filter(preg_split('/\r\n|[\r\n]/', $_POST['domains']));
            $clients = array_filter(preg_split('/\r\n|[\r\n]/', $_POST['clients']));

            $domainlist = '';
            $first = true;
            foreach ($domains as $domain) {
                if (!validDomainWildcard($domain) || validIP($domain)) {
                    $error .= 'Top Domains/Ads entry '.htmlspecialchars($domain).' is invalid (use only domains)!<br>';
                }
                if (!$first) {
                    $domainlist .= ',';
                } else {
                    $first = false;
                }
                $domainlist .= $domain;
            }

            $clientlist = '';
            $first = true;
            foreach ($clients as $client) {
                if (!validDomainWildcard($client) && !validIP($client)) {
                    $error .= 'Top Clients entry '.htmlspecialchars($client).' is invalid (use only host names and IP addresses)!<br>';
                }
                if (!$first) {
                    $clientlist .= ',';
                } else {
                    $first = false;
                }
                $clientlist .= $client;
            }

            // Set Top Lists options
            if (!strlen($error)) {
                // All entries are okay
                pihole_execute('-a setexcludedomains '.$domainlist);
                pihole_execute('-a setexcludeclients '.$clientlist);
                $success .= 'The API settings have been updated<br>';
            } else {
                $error .= 'The settings have been reset to their previous values';
            }

            // Set query log options
            if (isset($_POST['querylog-permitted'], $_POST['querylog-blocked'])) {
                pihole_execute('-a setquerylog all');
                $success .= 'All entries will be shown in Query Log';
            } elseif (isset($_POST['querylog-permitted'])) {
                pihole_execute('-a setquerylog permittedonly');
                $success .= 'Only permitted will be shown in Query Log';
            } elseif (isset($_POST['querylog-blocked'])) {
                pihole_execute('-a setquerylog blockedonly');
                $success .= 'Only blocked entries will be shown in Query Log';
            } else {
                pihole_execute('-a setquerylog nothing');
                $success .= 'No entries will be shown in Query Log';
            }

            break;

        case 'webUI':
            if (isset($_POST['boxedlayout'])) {
                pihole_execute('-a layout boxed');
            } else {
                pihole_execute('-a layout traditional');
            }
            if (isset($_POST['webtheme'])) {
                global $available_themes;
                if (array_key_exists($_POST['webtheme'], $available_themes)) {
                    exec('sudo /usr/bin/pihole -a theme '.$_POST['webtheme']);
                }
            }
            $success .= 'The webUI settings have been updated';

            break;

        case 'poweroff':
            pihole_execute('-a poweroff');
            $success = 'The system will poweroff in 5 seconds...';

            break;

        case 'reboot':
            pihole_execute('-a reboot');
            $success = 'The system will reboot in 5 seconds...';

            break;

        case 'restartdns':
            pihole_execute('-a restartdns');
            $success = 'The DNS server has been restarted';

            break;

        case 'flushlogs':
            pihole_execute('-f');
            $success = 'The Pi-hole log file has been flushed';

            break;

        case 'DHCP':
            if (isset($_POST['addstatic'])) {
                $mac = trim($_POST['AddMAC']);
                $ip = trim($_POST['AddIP']);
                $hostname = trim($_POST['AddHostname']);

                addStaticDHCPLease($mac, $ip, $hostname);

                break;
            }

            if (isset($_POST['removestatic'])) {
                $mac = $_POST['removestatic'];
                if (!validMAC($mac)) {
                    $error .= 'MAC address ('.htmlspecialchars($mac).') is invalid!<br>';
                }
                $mac = strtoupper($mac);

                if (!strlen($error)) {
                    pihole_execute('-a removestaticdhcp '.$mac);
                    $success .= 'The static address with MAC address '.htmlspecialchars($mac).' has been removed';
                }

                break;
            }

            if (isset($_POST['active'])) {
                // Validate from IP
                $from = $_POST['from'];
                if (!validIP($from)) {
                    $error .= 'From IP ('.htmlspecialchars($from).') is invalid!<br>';
                }

                // Validate to IP
                $to = $_POST['to'];
                if (!validIP($to)) {
                    $error .= 'To IP ('.htmlspecialchars($to).') is invalid!<br>';
                }

                // Validate router IP
                $router = $_POST['router'];
                if (!validIP($router)) {
                    $error .= 'Router IP ('.htmlspecialchars($router).') is invalid!<br>';
                }

                $domain = $_POST['domain'];

                // Validate Domain name
                if (!validDomain($domain)) {
                    $error .= 'Domain name '.htmlspecialchars($domain).' is invalid!<br>';
                }

                $leasetime = $_POST['leasetime'];

                // Validate Lease time length
                if (!is_numeric($leasetime) || intval($leasetime) < 0) {
                    $error .= 'Lease time '.htmlspecialchars($leasetime).' is invalid!<br>';
                }

                if (isset($_POST['useIPv6'])) {
                    $ipv6 = 'true';
                    $type = '(IPv4 + IPv6)';
                } else {
                    $ipv6 = 'false';
                    $type = '(IPv4)';
                }

                if (isset($_POST['DHCP_rapid_commit'])) {
                    $rapidcommit = 'true';
                } else {
                    $rapidcommit = 'false';
                }

                if (!strlen($error)) {
                    pihole_execute('-a enabledhcp '.$from.' '.$to.' '.$router.' '.$leasetime.' '.$domain.' '.$ipv6.' '.$rapidcommit);
                    $success .= 'The DHCP server has been activated '.htmlspecialchars($type);
                }
            } else {
                pihole_execute('-a disabledhcp');
                $success = 'The DHCP server has been deactivated';
            }

            break;

        case 'privacyLevel':
            $level = intval($_POST['privacylevel']);
            if ($level >= 0 && $level <= 4) {
                // Check if privacylevel is already set
                if (isset($piholeFTLConf['PRIVACYLEVEL'])) {
                    $privacylevel = intval($piholeFTLConf['PRIVACYLEVEL']);
                } else {
                    $privacylevel = 0;
                }

                // Store privacy level
                pihole_execute('-a privacylevel '.$level);

                if ($privacylevel > $level) {
                    pihole_execute('-a restartdns');
                    $success .= 'The privacy level has been decreased and the DNS resolver has been restarted';
                } elseif ($privacylevel < $level) {
                    $success .= 'The privacy level has been increased';
                } else {
                    $success .= 'The privacy level has not been changed';
                }
            } else {
                $error .= 'Invalid privacy level ('.$level.')!';
            }

            break;
            // Flush network table
        case 'flusharp':
            $output = pihole_execute('arpflush quiet');
            $error = '';
            if (is_array($output)) {
                $error = implode('<br>', $output);
            }
            if (strlen($error) == 0) {
                $success .= 'The network table has been flushed';
            }

            break;

        default:
            // Option not found
            $error = 'Invalid option';
    }
}

// Credit: http://stackoverflow.com/a/5501447/2087442
function formatSizeUnits($bytes)
{
    if ($bytes >= 1073741824) {
        $bytes = number_format($bytes / 1073741824, 2).' GB';
    } elseif ($bytes >= 1048576) {
        $bytes = number_format($bytes / 1048576, 2).' MB';
    } elseif ($bytes >= 1024) {
        $bytes = number_format($bytes / 1024, 2).' kB';
    } elseif ($bytes > 1) {
        $bytes = $bytes.' bytes';
    } elseif ($bytes == 1) {
        $bytes = $bytes.' byte';
    } else {
        $bytes = '0 bytes';
    }

    return $bytes;
}