1 files changed, 74 insertions, 14 deletions

diff --git a/library/HTMLPurifier/URIScheme.php b/library/HTMLPurifier/URIScheme.php
index 039710fd1..fe9e82cf2 100644
--- a/library/HTMLPurifier/URIScheme.php
+++ b/library/HTMLPurifier/URIScheme.php
@@ -3,40 +3,100 @@
 /**
  * Validator for the components of a URI for a specific scheme
  */
-class HTMLPurifier_URIScheme
+abstract class HTMLPurifier_URIScheme
 {
 
     /**
-     * Scheme's default port (integer)
+     * Scheme's default port (integer). If an explicit port number is
+     * specified that coincides with the default port, it will be
+     * elided.
+     * @type int
      */
     public $default_port = null;
 
     /**
-     * Whether or not URIs of this schem are locatable by a browser
+     * Whether or not URIs of this scheme are locatable by a browser
      * http and ftp are accessible, while mailto and news are not.
+     * @type bool
      */
     public $browsable = false;
 
     /**
+     * Whether or not data transmitted over this scheme is encrypted.
+     * https is secure, http is not.
+     * @type bool
+     */
+    public $secure = false;
+
+    /**
      * Whether or not the URI always uses <hier_part>, resolves edge cases
      * with making relative URIs absolute
+     * @type bool
      */
     public $hierarchical = false;
 
     /**
-     * Validates the components of a URI
-     * @note This implementation should be called by children if they define
-     *       a default port, as it does port processing.
-     * @param $uri Instance of HTMLPurifier_URI
-     * @param $config HTMLPurifier_Config object
-     * @param $context HTMLPurifier_Context object
-     * @return Bool success or failure
+     * Whether or not the URI may omit a hostname when the scheme is
+     * explicitly specified, ala file:///path/to/file. As of writing,
+     * 'file' is the only scheme that browsers support his properly.
+     * @type bool
      */
-    public function validate(&$uri, $config, $context) {
-        if ($this->default_port == $uri->port) $uri->port = null;
-        return true;
-    }
+    public $may_omit_host = false;
+
+    /**
+     * Validates the components of a URI for a specific scheme.
+     * @param HTMLPurifier_URI $uri Reference to a HTMLPurifier_URI object
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool success or failure
+     */
+    abstract public function doValidate(&$uri, $config, $context);
 
+    /**
+     * Public interface for validating components of a URI.  Performs a
+     * bunch of default actions. Don't overload this method.
+     * @param HTMLPurifier_URI $uri Reference to a HTMLPurifier_URI object
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool success or failure
+     */
+    public function validate(&$uri, $config, $context)
+    {
+        if ($this->default_port == $uri->port) {
+            $uri->port = null;
+        }
+        // kludge: browsers do funny things when the scheme but not the
+        // authority is set
+        if (!$this->may_omit_host &&
+            // if the scheme is present, a missing host is always in error
+            (!is_null($uri->scheme) && ($uri->host === '' || is_null($uri->host))) ||
+            // if the scheme is not present, a *blank* host is in error,
+            // since this translates into '///path' which most browsers
+            // interpret as being 'http://path'.
+            (is_null($uri->scheme) && $uri->host === '')
+        ) {
+            do {
+                if (is_null($uri->scheme)) {
+                    if (substr($uri->path, 0, 2) != '//') {
+                        $uri->host = null;
+                        break;
+                    }
+                    // URI is '////path', so we cannot nullify the
+                    // host to preserve semantics.  Try expanding the
+                    // hostname instead (fall through)
+                }
+                // first see if we can manually insert a hostname
+                $host = $config->get('URI.Host');
+                if (!is_null($host)) {
+                    $uri->host = $host;
+                } else {
+                    // we can't do anything sensible, reject the URL.
+                    return false;
+                }
+            } while (false);
+        }
+        return $this->doValidate($uri, $config, $context);
+    }
 }
 
 // vim: et sw=4 sts=4