From ab9b66e6becfdb944b2229a14e0ead7308a7bf92 Mon Sep 17 00:00:00 2001
From: David Waring <david.waring@rd.bbc.co.uk>
Date: Wed, 21 Jan 2015 14:09:45 +0000
Subject: [PATCH] uri: Fix parsing issues

Make host IPs in square brackets store only the IP, i.e. strip the brackets.
Strip leading whitespace characters in URIs.
Fail parsing when host part does not match any valid formats from RFC3986.

https://bugzilla.gnome.org/show_bug.cgi?id=743195
---
 gst/gsturi.c | 82 +++++++++++++++++++++++++++++++++-------------------
 1 file changed, 53 insertions(+), 29 deletions(-)

diff --git a/gst/gsturi.c b/gst/gsturi.c
index b1280fc728..37726a3c91 100644
--- a/gst/gsturi.c
+++ b/gst/gsturi.c
@@ -1256,6 +1256,13 @@ _gst_uri_escape_host (const gchar * host)
       G_URI_RESERVED_CHARS_SUBCOMPONENT_DELIMITERS, FALSE);
 }
 
+static gchar *
+_gst_uri_escape_host_colon (const gchar * host)
+{
+  return g_uri_escape_string (host,
+      G_URI_RESERVED_CHARS_SUBCOMPONENT_DELIMITERS ":", FALSE);
+}
+
 static gchar *
 _gst_uri_escape_path_segment (const gchar * segment)
 {
@@ -1504,21 +1511,27 @@ gst_uri_new_with_base (GstUri * base, const gchar * scheme,
  * gst_uri_from_string:
  * @uri: The URI string to parse.
  *
- * Parses a URI string into a new #GstUri object.
+ * Parses a URI string into a new #GstUri object. Will return NULL if the URI
+ * cannot be parsed.
  *
- * Returns: (transfer full): A new #GstUri object.
+ * Returns: (transfer full)(nullable): A new #GstUri object, or NULL.
  *
  * Since: 1.6
  */
 GstUri *
 gst_uri_from_string (const gchar * uri)
 {
+  const gchar *orig_uri = uri;
   GstUri *uri_obj;
 
   uri_obj = _gst_uri_new ();
 
   if (uri_obj && uri != NULL) {
     int i = 0;
+
+    /* be helpful and skip initial white space */
+    while (*uri == '\v' || g_ascii_isspace (*uri)) uri++;
+
     if (g_ascii_isalpha (uri[i])) {
       /* find end of scheme name */
       i++;
@@ -1532,13 +1545,12 @@ gst_uri_from_string (const gchar * uri)
       uri += i + 1;
     }
     if (uri[0] == '/' && uri[1] == '/') {
-      const gchar *eoa, *eoui, *eoh;
+      const gchar *eoa, *eoui, *eoh, *reoh;
       /* get authority [userinfo@]host[:port] */
       uri += 2;
       /* find end of authority */
-      eoa = strchr (uri, '/');
-      if (eoa == NULL)
-        eoa = uri + strlen (uri);
+      eoa = uri + strcspn (uri, "/?#");
+
       /* find end of userinfo */
       eoui = strchr (uri, '@');
       if (eoui != NULL && eoui < eoa) {
@@ -1548,31 +1560,37 @@ gst_uri_from_string (const gchar * uri)
       /* find end of host */
       if (uri[0] == '[') {
         eoh = strchr (uri, ']');
-        if (eoh == NULL || eoh >= eoa)
-          eoh = eoa - 1;
+        if (eoh == NULL || eoh > eoa) {
+          GST_DEBUG ("Unable to parse the host part of the URI '%s'.",
+                  orig_uri);
+	  _gst_uri_free (uri_obj);
+          return NULL;
+        }
+        reoh = eoh + 1;
+        uri++;
       } else {
-        eoh = strchr (uri, ':');
-        if (eoh == NULL || eoh >= eoa)
-          eoh = eoa - 1;
-        else
-          eoh--;
+        reoh = eoh = strchr (uri, ':');
+        if (eoh == NULL || eoh > eoa)
+          reoh = eoh = eoa;
       }
-      uri_obj->host = g_uri_unescape_segment (uri, eoh + 1, NULL);
-      uri = eoh + 1;
+      /* don't capture empty host strings */
+      if (eoh != uri)
+        uri_obj->host = g_uri_unescape_segment (uri, eoh, NULL);
+
+      uri = reoh;
       if (uri < eoa) {
-        /* if port number is malformed, do best effort and concat string */
+        /* if port number is malformed then we can't parse this */
         if (uri[0] != ':' || strspn (uri + 1, "0123456789") != eoa - uri - 1) {
-          gchar *tmp = uri_obj->host;
-          uri_obj->host = g_malloc (strlen (uri_obj->host) + eoa - uri + 1);
-          g_strlcpy (g_stpcpy (uri_obj->host, tmp), uri, eoa - uri + 1);
-          g_free (tmp);
-        } else {
-          /* otherwise treat port as unsigned decimal number */
+          GST_DEBUG ("Unable to parse host/port part of the URI '%s'.",
+                  orig_uri);
+          _gst_uri_free (uri_obj);
+          return NULL;
+        }
+        /* otherwise treat port as unsigned decimal number */
+        uri++;
+        while (uri < eoa) {
+          uri_obj->port = uri_obj->port * 10 + g_ascii_digit_value (*uri);
           uri++;
-          while (uri < eoa) {
-            uri_obj->port = uri_obj->port * 10 + g_ascii_digit_value (*uri);
-            uri++;
-          }
         }
       }
       uri = eoa;
@@ -1956,9 +1974,15 @@ gst_uri_to_string (const GstUri * uri)
   }
 
   if (uri->host != NULL) {
-    escaped = _gst_uri_escape_host (uri->host);
-    g_string_append (uri_str, escaped);
-    g_free (escaped);
+    if (strchr (uri->host, ':') != NULL) {
+      escaped = _gst_uri_escape_host_colon (uri->host);
+      g_string_append_printf (uri_str, "[%s]", escaped);
+      g_free (escaped);
+    } else {
+      escaped = _gst_uri_escape_host (uri->host);
+      g_string_append (uri_str, escaped);
+      g_free (escaped);
+    }
   }
 
   if (uri->port != GST_URI_NO_PORT)