fix(security): RQ-2426 — sandbox rule code (QuickJS-WASM)

dist/components/proxy-middleware/rule_action_processor/processors/modify_request_processor.js

@@ -25,16 +25,9 @@ const modify_request = (ctx, new_req) => {
         ctx.rq_request_body = new_req;
 };
 const modify_request_using_code = async (action, ctx) => {
-    let userFunction = null;
-    try {
-        userFunction = (0, utils_2.getFunctionFromString)(action.request);
-    }
-    catch (error) {
-        // User has provided an invalid function
-        return modify_request(ctx, "Can't parse Requestly function. Please recheck. Error Code 7201. Actual Error: " +
-            error.message);
-    }
-    if (!userFunction || typeof userFunction !== "function") {
+    // RQ-2426: validate the function source parses (compile-only, no execution)
+    // before running it in the sandboxed worker.
+    if (!(await (0, utils_2.isValidFunctionString)(action.request))) {
         // User has provided an invalid function
         return modify_request(ctx, "Can't parse Requestly function. Please recheck. Error Code 944.");
     }
@@ -58,7 +51,7 @@ const modify_request_using_code = async (action, ctx) => {
         catch (_a) {
             /*Do nothing -- could not parse body as JSON */
         }
-        finalRequest = await (0, utils_2.executeUserFunction)(ctx, userFunction, args);
+        finalRequest = await (0, utils_2.executeUserFunction)(ctx, action.request, args);
         if (finalRequest && typeof finalRequest === "string") {
             return modify_request(ctx, finalRequest);
         }

dist/components/proxy-middleware/rule_action_processor/processors/modify_response_processor.js

@@ -103,16 +103,9 @@ const modify_response_using_local = (action, ctx) => {
 };
 const modify_response_using_code = async (action, ctx) => {
     var _a, _b, _c, _d;
-    let userFunction = null;
-    try {
-        userFunction = (0, utils_2.getFunctionFromString)(action.response);
-    }
-    catch (error) {
-        // User has provided an invalid function
-        return modify_response(ctx, "Can't parse Requestly function. Please recheck. Error Code 7201. Actual Error: " +
-            error.message);
-    }
-    if (!userFunction || typeof userFunction !== "function") {
+    // RQ-2426: validate the function source parses (compile-only, no execution)
+    // before running it in the sandboxed worker.
+    if (!(await (0, utils_2.isValidFunctionString)(action.response))) {
         // User has provided an invalid function
         return modify_response(ctx, "Can't parse Requestly function. Please recheck. Error Code 944.");
     }

dist/utils/index.d.ts

@@ -1,2 +1,9 @@
-export declare const getFunctionFromString: (functionStringEscaped: any) => any;
+/**
+ * Verify a rule's code string parses WITHOUT executing it. Constructing
+ * `new Function(body)` compiles/parses the body but never runs it (the function
+ * is never called), so even an IIFE-shaped string cannot execute here. Avoids the
+ * `vm` module (unsupported in Electron's renderer); the sandboxed execution
+ * happens inside QuickJS.
+ */
+export declare const isValidFunctionString: (functionStringEscaped: string) => Promise<boolean>;
 export declare function executeUserFunction(ctx: any, functionString: string, args: any): Promise<any>;

dist/utils/sandbox-globals.d.ts

@@ -0,0 +1,32 @@
+/**
+ * sandbox-globals — the JavaScript SOURCE that runs INSIDE the QuickJS guest realm.
+ *
+ * These are plain strings injected into the sandbox; nothing here executes in the
+ * host. `index.ts` owns the host side (module/context lifecycle, the
+ * crypto/fetch/timer bridges, the pump loop).
+ *
+ * Organised by concern, each an IIFE that augments `globalThis` (except HARNESS,
+ * which must stay top-level so its `var`/`function` bindings are script-global).
+ * They are concatenated in DEPENDENCY ORDER into `SANDBOX_PRELUDE`:
+ *
+ *   ENCODING   atob/btoa, TextEncoder/Decoder, shared byte helpers (__rqb)
+ *   BINARY     Buffer, Blob                         (use __rqb)
+ *   URL        URL, URLSearchParams
+ *   HTTP_TYPES Headers, FormData, Request, Response
+ *   CLONE      structuredClone
+ *   CRYPTO     crypto.* + require()                 [host bridge: __hostCrypto]
+ *   NETWORK    fetch, XMLHttpRequest, WebSocket     [host bridge: __hostFetch]
+ *   TIMERS     setTimeout/setInterval/…, performance [host bridge: __hostTimer]
+ *   HARNESS    console + args/$sharedState/__OUTPUT (top-level; reads host-injected
+ *              __argsJson/__sharedStateJson; the user fn wrapper runs after it)
+ *
+ * Security: pure shims never touch the host. The bridged blocks (CRYPTO/NETWORK/
+ * TIMERS) call host functions that take and return only JSON-serialisable data —
+ * no host object is ever handed to the guest, so there is no escape surface.
+ * `String.raw` keeps regex/`\r\n` backslashes literal so they reach the sandbox JS.
+ */
+/**
+ * The complete in-guest prelude, concatenated in dependency order. index.ts
+ * appends the user-function wrapper after this.
+ */
+export declare const SANDBOX_PRELUDE: string;