[libsoup] Fix big control message payload

[Ignacio Casal Quinteiro <icq src gnome org>]

commit 14c33979e7383ae52c75903cad41c623820e0947
Author: Italo Guerrieri <guerital amazon it>
Date:   Thu Dec 28 11:30:32 2017 +0100

    Fix big control message payload
    
    Close connection with protocol error if the payload of a
    control message is bigger than 125 octets.
    Fix Authobahn test case 2.5.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=792113

 libsoup/soup-websocket-connection.c |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)
---
diff --git a/libsoup/soup-websocket-connection.c b/libsoup/soup-websocket-connection.c
index e9260b6..08387e5 100644
--- a/libsoup/soup-websocket-connection.c
+++ b/libsoup/soup-websocket-connection.c
@@ -152,6 +152,8 @@ typedef enum {
 static void queue_frame (SoupWebsocketConnection *self, SoupWebsocketQueueFlags flags,
                         gpointer data, gsize len, gsize amount);
 
+static void protocol_error_and_close (SoupWebsocketConnection *self);
+
 static void
 frame_free (gpointer data)
 {
@@ -358,11 +360,12 @@ send_message (SoupWebsocketConnection *self,
        outer = bytes->data;
        outer[0] = 0x80 | opcode;
 
-       /* If control message, truncate payload */
+       /* If control message, check payload size */
        if (opcode & 0x08) {
                if (length > 125) {
-                       g_warning ("Truncating WebSocket control message payload");
-                       length = 125;
+                       g_warning ("WebSocket control message payload exceeds size limit");
+                       protocol_error_and_close (self);
+                       return;
                }
 
                buffered_amount = 0;