rtspsrc: Add support to ignore x-server HEADER reply

When connecting to an RTSP server in tunnled mode (HTTP) the server
usually replies with a x-server header. This contains the address
of the intended streaming server. However some servers return an
"invalid" address. Here follows two examples when it might happen.

1. A server use Apache combined with a separate RTSP process to handle
   Https request on port 443. In this case Apache handle TLS and
   connects to the local RTSP server, which results in a local
   address 127.0.0.1 or ::1 in the x-server reply. This address is
   returned to the actual RTSP client in the x-server header.
   The client will receive this address and try to  connect to it
   and fail.

2. The client use a ipv6 link local address with a specified scope id
   fe80::aaaa:bbbb:cccc:dddd%eth0 and connects via Http on port 80.
   The RTSP server receives the connection and returns the address
   in the x-server header. The client will receive this address and
   try to connect to it "as is" without the scope id and fail.

In the case of streaming data from RTSP servers like 1. and 2. it's
useful to have the option to simply ignore the x-server header reply
and continue using the original address.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/1007>

2 files changed, 49 insertions, 2 deletions

diff --git a/gst/rtsp/gstrtspsrc.c b/gst/rtsp/gstrtspsrc.c
index 1306c2816..063b76174 100644
--- a/gst/rtsp/gstrtspsrc.c
+++ b/gst/rtsp/gstrtspsrc.c
@@ -292,6 +292,7 @@ gst_rtsp_backchannel_get_type (void)
 #define DEFAULT_ONVIF_MODE FALSE
 #define DEFAULT_ONVIF_RATE_CONTROL TRUE
 #define DEFAULT_IS_LIVE TRUE
+#define DEFAULT_IGNORE_X_SERVER_REPLY FALSE
 
 enum
 {
@@ -339,7 +340,8 @@ enum
   PROP_TEARDOWN_TIMEOUT,
   PROP_ONVIF_MODE,
   PROP_ONVIF_RATE_CONTROL,
-  PROP_IS_LIVE
+  PROP_IS_LIVE,
+  PROP_IGNORE_X_SERVER_REPLY
 };
 
 #define GST_TYPE_RTSP_NAT_METHOD (gst_rtsp_nat_method_get_type())
@@ -1007,6 +1009,41 @@ gst_rtspsrc_class_init (GstRTSPSrcClass * klass)
           DEFAULT_IS_LIVE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 
   /**
+   * GstRTSPSrc:ignore-x-server-reply
+   *
+   * When connecting to an RTSP server in tunneled mode (HTTP) the server
+   * usually replies with an x-server-ip-address header. This contains the
+   * address of the intended streaming server. However some servers return an
+   * "invalid" address. Here follows two examples when it might happen.
+   *
+   * 1. A server uses Apache combined with a separate RTSP process to handle
+   *    HTTPS requests on port 443. In this case Apache handles TLS and
+   *    connects to the local RTSP server, which results in a local
+   *    address 127.0.0.1 or ::1 in the header reply. This address is
+   *    returned to the actual RTSP client in the header. The client will
+   *    receive this address and try to connect to it and fail.
+   *
+   * 2. The client uses an IPv6 link local address with a specified scope id
+   *    fe80::aaaa:bbbb:cccc:dddd%eth0 and connects via HTTP on port 80.
+   *    The RTSP server receives the connection and returns the address
+   *    in the x-server-ip-address header. The client will receive this
+   *    address and try to connect to it "as is" without the scope id and
+   *    fail.
+   *
+   * In the case of streaming data from RTSP servers like 1 and 2, it's
+   * useful to have the option to simply ignore the x-server-ip-address
+   * header reply and continue using the original address.
+   *
+   * Since: 1.20
+   */
+  g_object_class_install_property (gobject_class, PROP_IGNORE_X_SERVER_REPLY,
+      g_param_spec_boolean ("ignore-x-server-reply",
+          "Ignore x-server-ip-address",
+          "Whether to ignore the x-server-ip-address server header reply",
+          DEFAULT_IGNORE_X_SERVER_REPLY,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  /**
    * GstRTSPSrc::handle-request:
    * @rtspsrc: a #GstRTSPSrc
    * @request: a #GstRTSPMessage
@@ -1749,6 +1786,9 @@ gst_rtspsrc_set_property (GObject * object, guint prop_id, const GValue * value,
     case PROP_IS_LIVE:
       rtspsrc->is_live = g_value_get_boolean (value);
       break;
+    case PROP_IGNORE_X_SERVER_REPLY:
+      rtspsrc->ignore_x_server_reply = g_value_get_boolean (value);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -1916,6 +1956,9 @@ gst_rtspsrc_get_property (GObject * object, guint prop_id, GValue * value,
     case PROP_IS_LIVE:
       g_value_set_boolean (value, rtspsrc->is_live);
       break;
+    case PROP_IGNORE_X_SERVER_REPLY:
+      g_value_set_boolean (value, rtspsrc->ignore_x_server_reply);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -5112,8 +5155,11 @@ gst_rtsp_conninfo_connect (GstRTSPSrc * src, GstRTSPConnInfo * info,
             accept_certificate_cb, src, NULL);
       }
 
-      if (info->url->transports & GST_RTSP_LOWER_TRANS_HTTP)
+      if (info->url->transports & GST_RTSP_LOWER_TRANS_HTTP) {
         gst_rtsp_connection_set_tunneled (info->connection, TRUE);
+        gst_rtsp_connection_set_ignore_x_server_reply (info->connection,
+            src->ignore_x_server_reply);
+      }
 
       if (src->proxy_host) {
         GST_DEBUG_OBJECT (src, "setting proxy %s:%d", src->proxy_host,
diff --git a/gst/rtsp/gstrtspsrc.h b/gst/rtsp/gstrtspsrc.h
index 469d2dace..5af00f9e5 100644
--- a/gst/rtsp/gstrtspsrc.h
+++ b/gst/rtsp/gstrtspsrc.h
@@ -278,6 +278,7 @@ struct _GstRTSPSrc {
   gboolean          onvif_mode;
   gboolean          onvif_rate_control;
   gboolean          is_live;
+  gboolean          ignore_x_server_reply;
 
   /* state */
   GstRTSPState       state;