defender-legacy-ip-detection.php

<?php

add_action( 'plugins_loaded', function(){ 
	if ( ! defined( 'DEFENDER_VERSION' ) ) {
		return; // Defender is not installed/enabled.
	}

	if ( ! class_exists( 'Defender_Legacy_IP_Detection' ) ) {
		class Defender_Legacy_IP_Detection {
			use WP_Defender\Traits\IP;

			private static $instance;

			public static function get() {
				if ( null === self::$instance ) {
					self::$instance = new self();
				}
				return self::$instance;
			}

			public function __construct() {
				add_filter( 'defender_user_ip', array( $this, 'get_user_ip' ) );
			}

			private function is_cloudflare_request() {
				if ( isset( $_SERVER['HTTP_CF_CONNECTING_IP'] ) ) {
					return true;
				}
				if ( isset( $_SERVER['HTTP_CF_IPCOUNTRY'] ) ) {
					return true;
				}
				if ( isset( $_SERVER['HTTP_CF_RAY'] ) ) {
					return true;
				}
				if ( isset( $_SERVER['HTTP_CF_VISITOR'] ) ) {
					return true;
				}
		
				return false;
			}

			private function cloudflare_ip_ranges() {
				return array(
					array(
						'173.245.48.0/20',
						'103.21.244.0/22',
						'103.22.200.0/22',
						'103.31.4.0/22',
						'141.101.64.0/18',
						'108.162.192.0/18',
						'190.93.240.0/20',
						'188.114.96.0/20',
						'197.234.240.0/22',
						'198.41.128.0/17',
						'162.158.0.0/15',
						'172.64.0.0/13',
						'131.0.72.0/22',
						'104.16.0.0/13',
						'104.24.0.0/14',
					),
					array(
						'2400:cb00::/32',
						'2606:4700::/32',
						'2803:f800::/32',
						'2405:b500::/32',
						'2405:8100::/32',
						'2a06:98c0::/29',
						'2c0f:f248::/32',
					),
				);
			}
			
			private function cloudflare_ip() {
				if ( $this->is_cloudflare_request() ) {
					// This looks like it come from cloudflare, so this should contain the actual IP,
					// and REMOTE_ADDR contains cloudflare IP.
					[$cloudflare_ipv4_range, $cloudflare_ipv6_range] = $this->cloudflare_ip_ranges();
					$ip_helper   = new \WP_Defender\Extra\IP_Helper();
					$remote_addr = isset( $_SERVER['REMOTE_ADDR'] ) ?
						filter_var( $_SERVER['REMOTE_ADDR'], FILTER_VALIDATE_IP ) :
						false;
					$cf_con_ip   = isset( $_SERVER['HTTP_CF_CONNECTING_IP'] ) ?
						filter_var( $_SERVER['HTTP_CF_CONNECTING_IP'], FILTER_VALIDATE_IP ) :
						false;
		
					if ( $remote_addr === $cf_con_ip ) {
						return $cf_con_ip;
					} else if ( false === $remote_addr || false === $cf_con_ip ) {
						return false;
					}
		
					$is_cloudflare_proxy_ip = false;
					if ( $this->is_v4( $remote_addr ) ) {
						foreach ( $cloudflare_ipv4_range as $cf_ip ) {
							if ( $ip_helper->ipv4_in_range( $remote_addr, $cf_ip ) ) {
								$is_cloudflare_proxy_ip = true;
								break;
							}
						}
					} elseif ( $this->is_v6( $remote_addr ) ) {
						foreach ( $cloudflare_ipv6_range as $cf_ip ) {
							if ( $ip_helper->ipv6_in_range( $remote_addr, $cf_ip ) ) {
								$is_cloudflare_proxy_ip = true;
								break;
							}
						}
					}
		
					if ( true === $is_cloudflare_proxy_ip ) {
						return $cf_con_ip;
					}
				}
		
				return false;
			}

			public function get_user_ip() {
				// Check if it's any cloudflare IP.
				$cf_ip = $this->cloudflare_ip();

				if ( ! empty( $cf_ip ) && filter_var( $cf_ip, FILTER_VALIDATE_IP ) ) {
					return $cf_ip;
				}
		
				$headers = array(
					'HTTP_CLIENT_IP',
					'HTTP_X_REAL_IP',
					'HTTP_X_FORWARDED_FOR',
					'HTTP_X_FORWARDED',
					'HTTP_X_CLUSTER_CLIENT_IP',
					'HTTP_FORWARDED_FOR',
					'HTTP_FORWARDED',
					'REMOTE_ADDR',
				);

				$ip = '';

				foreach ( $headers as $key ) {
					if ( array_key_exists( $key, $_SERVER ) && ! empty( $_SERVER[ $key ] ) ) {
						$ip_array = explode( ',', $_SERVER[ $key ] );
						$tmp_ip   = array_shift( $ip_array );
						$tmp_ip   = trim( $tmp_ip );
						if ( $this->check_validate_ip( $tmp_ip ) ) {
							$ip = $tmp_ip;
							break;
						}
					}
				}
		
				return $ip;
			}
		}
		Defender_Legacy_IP_Detection::get();
	} 
}, 10 );