<?php
/* IPAddr.class.php - IPv4/IPv6 Address Class
 * Copyright (C) 2011-2013  Philipp Kreil (pk910)
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License 
 * along with this program. If not, see <http://www.gnu.org/licenses/>. 
 */

class IPAddr {
	private static $pattern_IPv6 = '/^((([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){6}:[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){5}:([0-9A-Fa-f]{1,4}:)?[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){4}:([0-9A-Fa-f]{1,4}:){0,2}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){3}:([0-9A-Fa-f]{1,4}:){0,3}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){2}:([0-9A-Fa-f]{1,4}:){0,4}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){6}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))|(([0-9A-Fa-f]{1,4}:){0,5}:((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))|(::([0-9A-Fa-f]{1,4}:){0,5}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b))|([0-9A-Fa-f]{1,4}::([0-9A-Fa-f]{1,4}:){0,5}[0-9A-Fa-f]{1,4})|(::([0-9A-Fa-f]{1,4}:){0,6}[0-9A-Fa-f]{1,4})|(([0-9A-Fa-f]{1,4}:){1,7}:))(|\/[0-9]{1,3})$/';
	private static $pattern_IPv4 = '/^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}(|\/[0-9]{1,2})$/';
	private $ip6 = array();
	private $addr_is_ipv6 = false;

	public function __construct($parse_ip) {
		for($i = 0; $i < 8; $i++)
			$this->ip6[$i] = 0;
		
		if($parse_ip == null) {
			//nothing
		} elseif(preg_match(self::$pattern_IPv6, $parse_ip)) {
			$this->parseIPv6($parse_ip);
		} elseif(preg_match(self::$pattern_IPv4, $parse_ip)) {
			$this->parseIPv4($parse_ip);
		}
	}

	public function parseIPv6($ipv6) {
		if(substr($ipv6,0,2) == "::") $ipv6 = substr($ipv6, 1);
		if(substr($ipv6,-2) == "::") $ipv6 = substr($ipv6, 0, -1);
		$ipv6blocks = explode(":", $ipv6);
		$j = 0;
		foreach($ipv6blocks as $i => $block) {
			if($block == "") {
				$skipBlocks = 8 - count($ipv6blocks);
				$j += $skipBlocks + 1;
			} else if(strpos($block, '.')) { //ipv4 mapped
				$this->parseIPv4($block);
				return;
			} else {
				$this->ip6[$j++] = hexdec($block);
			}
		}
		$this->addr_is_ipv6 = true;
	}

	public function parseIPv4($ipv4) {
		$ipv4blocks = explode(".",$ipv4);
		$this->ip6[6] = intval($ipv4blocks[0]) << 8;
		$this->ip6[6] |= intval($ipv4blocks[1]);
		$this->ip6[7] = intval($ipv4blocks[2]) << 8;
		$this->ip6[7] |= intval($ipv4blocks[3]);
		$this->addr_is_ipv6 = false;
	}

	public function isIPv6() {
		return $this->addr_is_ipv6;
	}
	
	public function isLocalAddress() {
		/* checks if address is out of:
		* 127.0.0.1/32
		* 10.0.0.0/8
		* 192.168.0.0/16
		* 172.16.0.0/12
		* ::1/128
		* fc00::/7
		*/
		if($this->addr_is_ipv6) {
			if(
				(($this->ip6[0] & 0xFE00) == 0xFC00) || /* fc00::/7 */
				($this->ip6[0] == 0 && $this->ip6[1] == 0 && $this->ip6[2] == 0 && $this->ip6[3] == 0 && 
				 $this->ip6[4] == 0 && $this->ip6[5] == 0 && $this->ip6[6] == 0 && $this->ip6[7] == 1)
			  )
				return true;
		} else {
			if(
				(($this->ip6[6] & 0xFFFF) == 0x7F00 && ($this->ip6[7] & 0xFFFF) == 0x0001) || /* 127.0.0.1/32 */
				(($this->ip6[6] & 0xFF00) == 0x0A00) || /* 10.0.0.0/8 */
				(($this->ip6[6] & 0xFFF0) == 0xAC10) || /* 172.16.0.0/12 */
				(($this->ip6[6] & 0xFFFF) == 0xC0A8) /* 192.168.0.0/16 */
			  )
				return true;
		}
		return false;
	}

	public function getAddress($options = array()) {
		$shorten_ipv6 = (isset($options['shorten_ipv6']) ? $options['shorten_ipv6'] : true);
		$ipv4_mapped = (isset($options['ipv4_mapped']) ? $options['ipv4_mapped'] : true);
		if($this->isIPv6()) {
			$max_start = 0;
			$max_zeros = 0;
			$curr_zeros = 0;
			if($shorten_ipv6) {
				for ($i = 0; $i < 8; $i++) {
					if ($this->ip6[$i] == 0)
					$curr_zeros++;
					else if ($curr_zeros > $max_zeros) {
						$max_start = $i - $curr_zeros;
						$max_zeros = $curr_zeros;
						$curr_zeros = 0;
					}
				}
				if ($curr_zeros > $max_zeros) {
					$max_start = $i - $curr_zeros;
					$max_zeros = $curr_zeros;
				}
			}
			$ipv6 = "";
			for($i = 0; $i < 8; $i++) {
				if($max_zeros > 1 && $i == $max_start) {
					$ipv6 .= "::";
					$i += $max_zeros - 1;
				} else {
					if($ipv6 != "") $ipv6 .= ":";
					$hex = dechex($this->ip6[$i]);
					if(!$shorten_ipv6) {
						while(strlen($hex) < 4)
							$hex = '0'.$hex;
					}
					$ipv6 .= $hex;
				}
			}
			return $ipv6;
		} else {
			$ipv4 = array();
			$ipv4[0] = ($this->ip6[6] >> 8) & 0xff;
			$ipv4[1] = ($this->ip6[6]) & 0xff;
			$ipv4[2] = ($this->ip6[7] >> 8) & 0xff;
			$ipv4[3] = ($this->ip6[7]) & 0xff;
			$ipv4 = implode(".", $ipv4);
			if($ipv4_mapped)
				$ipv4 = '::ffff:'.$ipv4;
			return $ipv4;
		}
	}
	
	public function ipMatches($ip) {
		if(!is_a($ip, __CLASS__)) {
			$class = __CLASS__;
			$ip = new $class($ip);
		}
		if(!$ip)
			return false;
		if($this->addr_is_ipv6 xor $ip->addr_is_ipv6)
			return false;
		$i = ($this->addr_is_ipv6 ? 0 : 6);
		for(;$i < 8; $i++) {
			if($this->ip6[$i] != $ip->ip6[$i])
				return false;
		}
		return true;
	}

}

?>