Merge branch 'master' of git://github.com/kohana/core

classes/kohana/validate.php

@@ -144,18 +144,55 @@ public static function email_domain($email)
 	 */
 	public static function url($url)
 	{
-		// Regex taken from http://fightingforalostcause.net/misc/2006/compare-email-regex.php
-		// Added the scheme and path parts to test URLs
+		// Based on http://www.apps.ietf.org/rfc/rfc1738.html#sec-5
+		if ( ! preg_match(
+			'~^
 
-		$scheme = '[a-z0-9+-.]+';
-		$host   = '(([a-z0-9]{1}[a-z0-9-]+[a-z0-9]{1}|[a-z])\.?)+([a-z]{2,6})?';
-		$ipaddr = '(\d{1,3}.){3}\d{1,3}';
-		$port   = '(\:\d{1,5})?';
-		$path   = '(/.+)?';
+			# scheme
+			[-a-z0-9+.]++://
 
-		$regex  = "!^{$scheme}://({$host}|{$ipaddr}){$port}{$path}$!i";
+			# username:password (optional)
+			(?:
+				    [-a-z0-9$_.+!*\'(),;?&=%]++   # username
+				(?::[-a-z0-9$_.+!*\'(),;?&=%]++)? # password (optional)
+				@
+			)?
 
-		return (bool) preg_match($regex, $url);
+			(?:
+				# ip address
+				\d{1,3}+(?:\.\d{1,3}+){3}+
+
+				| # or
+
+				# hostname (captured)
+				(
+					     (?!-)[-a-z0-9]{1,63}+(?<!-)
+					(?:\.(?!-)[-a-z0-9]{1,63}+(?<!-)){0,126}+
+				)
+			)
+
+			# port (optional)
+			(?::\d{1,5}+)?
+
+			# path (optional)
+			(?:/.*)?
+
+			$~iDx', $url, $matches))
+			return FALSE;
+
+		// We matched an IP address
+		if ( ! isset($matches[1]))
+			return TRUE;
+
+		// Check maximum length of the whole hostname
+		// http://en.wikipedia.org/wiki/Domain_name#cite_note-0
+		if (strlen($matches[1]) > 253)
+			return FALSE;
+
+		// An extra check for the top level domain
+		// It must start with a letter
+		$tld = ltrim(substr($matches[1], (int) strrpos($matches[1], '.')), '.');
+		return ctype_alpha($tld[0]);
 	}
 
 	/**