Fix regex to work for Stalwart and modern Postfix

Author: christiaangoossens

tls_icon.php

@@ -2,7 +2,7 @@
 
 class tls_icon extends rcube_plugin
 {
-	const POSTFIX_TLS_REGEX = "/\(using (TLS[^()]+(?:\([^)]+\))?)\)/im";
+	const POSTFIX_TLS_REGEX = "/\(using (TLS(?:[^()]|\([^()]*\))*)\)/im";
 	const POSTFIX_LOCAL_REGEX = "/\([a-zA-Z]*, from userid [0-9]*\)/im";
 	const SENDMAIL_TLS_REGEX = "/\(version=(TLS.*)\)(\s+for|;)/im";
 
@@ -59,8 +59,10 @@ public function message_headers($p)
 				return $p;
 			}
 
-			if (preg_match_all(tls_icon::POSTFIX_TLS_REGEX, $Received, $items, PREG_PATTERN_ORDER) ||
-				preg_match_all(tls_icon::SENDMAIL_TLS_REGEX, $Received, $items, PREG_PATTERN_ORDER)) {
+			if (
+				preg_match_all(tls_icon::POSTFIX_TLS_REGEX, $Received, $items, PREG_PATTERN_ORDER) ||
+				preg_match_all(tls_icon::SENDMAIL_TLS_REGEX, $Received, $items, PREG_PATTERN_ORDER)
+			) {
 				$data = $items[1][0];
 				$this->icon_img .= '<img class="lock_icon" src="plugins/tls_icon/lock.svg" title="' . htmlentities($data) . '" />';
 			} elseif (preg_match_all(tls_icon::POSTFIX_LOCAL_REGEX, $Received, $items, PREG_PATTERN_ORDER)) {