1<?php
2
3/**
4 * Validates an IPv4 address
5 * @author Feyd @ forums.devnetwork.net (public domain)
6 */
7class HTMLPurifier_AttrDef_URI_IPv4 extends HTMLPurifier_AttrDef
8{
9
10    /**
11     * IPv4 regex, protected so that IPv6 can reuse it.
12     * @type string
13     */
14    protected $ip4;
15
16    /**
17     * @param string $aIP
18     * @param HTMLPurifier_Config $config
19     * @param HTMLPurifier_Context $context
20     * @return bool|string
21     */
22    public function validate($aIP, $config, $context)
23    {
24        if (!$this->ip4) {
25            $this->_loadRegex();
26        }
27
28        if (preg_match('#^' . $this->ip4 . '$#s', $aIP)) {
29            return $aIP;
30        }
31        return false;
32    }
33
34    /**
35     * Lazy load function to prevent regex from being stuffed in
36     * cache.
37     */
38    protected function _loadRegex()
39    {
40        $oct = '(?:25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]|[0-9])'; // 0-255
41        $this->ip4 = "(?:{$oct}\\.{$oct}\\.{$oct}\\.{$oct})";
42    }
43}
44
45// vim: et sw=4 sts=4
46