Work-around for serviceWorker loads bypassing webRequest.

src/bg/RequestGuard.js

@@ -72,6 +72,7 @@ var RequestGuard = (() => {
     },
 
     initTab(tabId, records = this.newRecords()) {
+      if (tabId < 0) return;
       this.map.set(tabId, records);
       return records;
     },
@@ -109,6 +110,8 @@ var RequestGuard = (() => {
     },
 
     record(request, what, optValue) {
+      let {tabId} = request;
+      if (tabId < 0) return;
       let records = this._record(request, what, optValue);
       if (records) {
         this.updateTab(request.tabId);
@@ -118,6 +121,7 @@ var RequestGuard = (() => {
     _pendingTabs: new Set(),
 
     updateTab(tabId) {
+      if (tabId < 0) return;
       if (this._pendingTabs.size === 0) {
         window.setTimeout(() => { // clamp UI updates
           for (let tabId of this._pendingTabs) {
@@ -217,7 +221,7 @@ var RequestGuard = (() => {
         case "pageshow":
           TabStatus.recordAll(sender.tab.id, message.seen);
           return true;
-        case "enable":
+        case "enable": {
           let {url, documentUrl, policyType} = message;
           let TAG = `<${policyType.toUpperCase()}>`;
           let origin = Sites.origin(url);
@@ -258,10 +262,17 @@ var RequestGuard = (() => {
             ns.savePolicy();
           }
           return true;
-          case "canScript":
-            let records = TabStatus.map.get(sender.tab.id);
-            debug("Records.noscriptFrames %o, canScript: %s", records && records.noscriptFrames, !(records && records.noscriptFrames[sender.frameId]));
-            return !(records && records.noscriptFrames[sender.frameId]);
+        }
+        case "canScript": {
+          let {frameId, url, tab} = sender;
+          let tabId = tab.id;
+          let records = TabStatus.map.get(tabId);
+          let noscriptFrames = records && records.noscriptFrames;
+          let canScript = !(noscriptFrames && noscriptFrames[sender.frameId]);
+          let shouldScript = ns.isEnforced(tabId) && ns.policy.can(url, "script");
+          debug("Frame %s %s of  %o, canScript: %s, shouldScript: %s", frameId, url, noscriptFrames, canScript, shouldScript);
+          return {canScript, shouldScript};
+        }
       }
     },
 

src/content/content.js

@@ -2,6 +2,8 @@
 
  // debug = () => {}; // XPI_ONLY
  
+window.canScript = true;
+ 
 function createHTMLElement(name) {
   return document.createElementNS("http://www.w3.org/1999/xhtml", name);
 }
@@ -20,7 +22,6 @@ function probe() {
 
 var _ = browser.i18n.getMessage;
 
-var canScript = true;
 
 var embeddingDocument = false;
 
@@ -86,26 +87,49 @@ let notifyPage = () => {
 }
 
 var queryingCanScript = false;
+var caps = {};
+
 async function init(oldPage = false) {
   if (queryingCanScript) return;
+  if (document.URL === "about:blank") {
+    return;
+  }
   queryingCanScript = true;
-  debug(`NoScript init() called in document %s, scripting=%s, content type %s readyState %s`,
-    document.URL, canScript, document.contentType, document.readyState);
+
+  debug(`init() called in document %s, contentType %s readyState %s`,
+    document.URL, document.contentType, document.readyState);
   
   try {
-    canScript = document.URL === "about:blank" || await browser.runtime.sendMessage({type: "canScript"});
-    if (oldPage && canScript) {
+    let {canScript, shouldScript} = await browser.runtime.sendMessage({type: "canScript"});
+    debug(`document %s, canScript=%s, shouldScript=%s, readyState %s`, document.URL, canScript, shouldScript, document.readyState);
+    if (canScript) {
+      if (oldPage) {
         probe();
         setTimeout(() => init(), 100);
         return;
       }
+      if (!shouldScript) {
+        // Something wrong: scripts can run, permissions say they shouldn't.
+        // Was webRequest bypassed by caching/session restore/service workers?
+        let noCache = !!navigator.serviceWorker.controller;
+        if (noCache) {
+           for (let r of await navigator.serviceWorker.getRegistrations()) {
+             await r.unregister();
+           }
+        }
+        debug("Reloading %s (%s)", document.URL, noCache  ? "no cache" : "cached");
+        location.reload(noCache);
+        return;
+      }
+    }
+    window.canScript = canScript;
     init = () => {};
-    debug("canScript:", canScript);
   } catch (e) {
     debug("Error querying canScript", e);
-    if (document.readyState !== "complete" &&
+    if (!oldPage &&
       /Receiving end does not exist/.test(e.message)) {
-      window.location.reload(false);
+      // probably startup and bg page not ready yet, hence no CSP: reload!
+      location.reload(false);
     } else {
       setTimeout(() => init(oldPage), 100);
     }
@@ -126,8 +150,8 @@ async function init(oldPage = false) {
     }
   );
 
-  debug(`Loading NoScript in document %s, scripting=%s, content type %s readyState %s`,
-    document.URL, canScript, document.contentType, document.readyState);
+  debug(`Loading NoScript in document %s, scripting=%s, readyState %s`,
+    document.URL, canScript, document.readyState);
 
   if (/application|video|audio/.test(document.contentType)) {
     debug("Embedding document detected");