From eb85395a01b735294d70551abbecb78838000a05 Mon Sep 17 00:00:00 2001
From: hackademix
Date: Sun, 9 Sep 2018 08:21:03 +0200
Subject: Fixed message handling regression causing incompatibilities with
 embedders and potential internal loops.

---
 src/lib/Messages.js | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

(limited to 'src')

diff --git a/src/lib/Messages.js b/src/lib/Messages.js
index 8152555..11b9010 100644
--- a/src/lib/Messages.js
+++ b/src/lib/Messages.js
@@ -3,7 +3,14 @@
   let handlers = new Set();
 
   let dispatch = async (msg, sender) => {
-    let {__meta} = msg;
+    let {__meta, _messageName} = msg;
+    if (!__meta) {
+      // legacy message from embedder?
+      if (!_messageName) {
+        throw new Error(`NoScript cannot handle message %s`, JSON.stringify(msg));
+      }
+      __meta = {name: _messageName};
+    }
     let {name} = __meta;
     let answers = [];
     for (let h of handlers) {
@@ -17,8 +24,11 @@
         answers.length === 1 ? answers.pop(): Promise.all(answers)
       );
     }
-    let context = typeof window === "object" && window.location || null;
+    let context = typeof window === "object" && window.location.href || null;
     let originalSender = __meta.originalSender || sender;
+    if (context === originalSender.url || context === sender.url) {
+      throw new Error("Message %s (%o) looping to its sender (%s)", name, msg, context);
+    }
     console.debug("Warning: no handler for message %o in context %s", msg, context);
     if (originalSender.tab && originalSender.tab.id) {
       // if we're receiving a message from content, there might be another
-- 
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