fix(mv2): [temporary workaround] privileged api leakage due to same-origin

src/runtime/content/exec_script.ts

@@ -51,11 +51,31 @@ export default class ExecScript {
     });
     this.GM_info = GMApi.GM_info(this.scriptRes);
     this.proxyMessage = new ProxyMessageManager(message);
+    let isSandbox = false;
     if (scriptFunc) {
       this.scriptFunc = scriptFunc;
     } else {
       // 构建脚本资源
-      this.scriptFunc = compileScript(this.scriptRes.code);
+      const scriptType = this.scriptRes.type;
+      let scriptCode = this.scriptRes.code;
+      if ((scriptType === 2 || scriptType === 3) && scriptCode.length > 0) {
+        isSandbox = true;
+        // background script / scheduled script
+        // we need to remove the access to chrome or browser in FirefoxMV2
+        // since sandbox manifest support is still missing.
+        const arr = scriptCode.split("\n");
+        for (let i = 0, l = arr.length; i < l; i++) {
+          const t = arr[i].trim();
+          if (!t || t.startsWith("//")) continue;
+          const codeGen = (target: string, property: string, value: string): string => {
+            return `try { Object.defineProperty(${target}, "${property}", { get() { return ${value}; }, configurable: false }); } catch {}`;
+          };
+          arr.splice(i, 0, `let chrome = {}, browser = undefined, frameElement = null, parent = window, top = window; try { window.parent = window; } catch {} ${codeGen("window", "parent", "this")} ${codeGen("window", "top", "this")} ${codeGen("window", "chrome", "{}")} ${codeGen("window", "browser", "undefined")} ${codeGen("window", "frameElement", "null")}`)
+          scriptCode = arr.join("\n");
+          break;
+        }
+      }
+      this.scriptFunc = compileScript(scriptCode);
     }
     if (scriptRes.grantMap.none) {
       // 不注入任何GM api
@@ -70,7 +90,8 @@ export default class ExecScript {
       this.proxyContent = proxyContext(
         global,
         this.sandboxContent,
-        thisContext
+        thisContext,
+        isSandbox
       );
     }
   }

src/runtime/content/utils.ts

@@ -93,7 +93,8 @@ export function warpObject(thisContext: Object, ...context: Object[]) {
 export function proxyContext(
   global: any,
   context: any,
-  thisContext?: { [key: string]: any }
+  thisContext?: { [key: string]: any },
+  isSandbox: boolean = false
 ) {
   const special = Object.assign(writables);
   // 处理某些特殊的属性
@@ -131,10 +132,15 @@ export function proxyContext(
           return proxy;
         case "top":
         case "parent":
+          if (isSandbox) return proxy;
           if (global[name] === global.self) {
             return special.global || proxy;
           }
           return global[name];
+        // eslint-disable-next-line no-fallthrough
+        case "frameElement":
+          if (isSandbox) return null;
+        // eslint-disable-next-line no-fallthrough
         default:
           break;
       }
@@ -195,6 +201,10 @@ export function proxyContext(
         case "top":
         case "parent":
           return true;
+        // eslint-disable-next-line no-fallthrough
+        case "frameElement":
+          if (isSandbox) return true;
+        // eslint-disable-next-line no-fallthrough
         default:
           break;
       }
@@ -233,6 +243,13 @@ export function proxyContext(
         case "self":
         case "globalThis":
           return false;
+        case "top":
+        case "parent":
+          if (isSandbox) return false;
+        // eslint-disable-next-line no-fallthrough
+        case "frameElement":
+          if (isSandbox) return false;
+        // eslint-disable-next-line no-fallthrough
         default:
       }
       if (has(special, name)) {