diff --git a/phpseclib/Crypt/Random.php b/phpseclib/Crypt/Random.php
index e5c819c76..8f53eb319 100644
--- a/phpseclib/Crypt/Random.php
+++ b/phpseclib/Crypt/Random.php
@@ -98,7 +98,7 @@ static function string($length)
             }
             if ($fp !== true && $fp !== false) { // surprisingly faster than !is_bool() or is_resource()
                 $temp = fread($fp, $length);
-                if (strlen($temp) != $length) {
+                if (strlen($temp) == $length) {
                     return $temp;
                 }
             }