Valruin's Friends

Php woes, and perhaps a solution for others.
So, I recently had to write a small script in php that allowed me to block ip's or ip ranges listed in a text file.

There are a number of solutions for this scattered about the web, but I didn't like any of the implementations. Some were buggy, others didn't do exactly what I wanted, and the remainder didn't fit into my coding style. Plus, I like to write my own code, it avoids licencing issues.

Hers the code I came up with.

<?php	
	function isBanned($ip) {
		$bannedFile=("bannedIps.dat");
		$fh = fopen($bannedFile, "r");
		if (!$fh) {
			return true;
		} else {
			while ($line = fgets($fh)) {
				if (ipMatch($line, $ip)) {
					fclose($fh);
					return true;
				}
			}
			fclose($fh);
			return false;
		}
	}
	
	function ipMatch($thisIp, $ip) {
		$needle = strpos($thisIp, "*", 0);
		if ($needle !== false) {
			$thisIp = substr($thisIp, 0, ($needle-1));
		}
		$haystack = $ip;
		$needle = $thisIp;
		rtrim($haystack);
		$needle=preg_replace("/\s*/", "", $needle);
		if (preg_match("/^$needle/", $haystack)) {
			return true;
		}
		return false;
	}
?>

To use it, just save it as "ipban.php" or something similar, then include("ipban.php") in your main code, and then if (isBanned("$ip"))...

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