From 0998a39fbb1f9026571aa54c892b27cd9509be23 Mon Sep 17 00:00:00 2001
From: Rick Waldron <waldron.rick@gmail.com>
Date: Fri, 9 Feb 2024 13:20:42 -0500
Subject: [PATCH] fix: do not remap crypto if remapTypedArrays is false (#449)

---
 .../near-membrane-dom/src/browser-realm.ts    |  9 +++----
 packages/near-membrane-dom/src/window.ts      | 20 +++++++++++++---
 test/membrane/binary-data.spec.js             | 24 +++++++++++++++++++
 3 files changed, 46 insertions(+), 7 deletions(-)

diff --git a/packages/near-membrane-dom/src/browser-realm.ts b/packages/near-membrane-dom/src/browser-realm.ts
index ec9169dd..b8488ef8 100644
--- a/packages/near-membrane-dom/src/browser-realm.ts
+++ b/packages/near-membrane-dom/src/browser-realm.ts
@@ -80,7 +80,7 @@ function createIframeVirtualEnvironment(
         instrumentation,
         keepAlive = true,
         liveTargetCallback,
-        remapTypedArrays,
+        remapTypedArrays = true,
         signSourceCallback,
         // eslint-disable-next-line prefer-object-spread
     } = ObjectAssign({ __proto__: null }, providedOptions) as BrowserEnvironmentOptions;
@@ -94,7 +94,8 @@ function createIframeVirtualEnvironment(
         typeof globalObjectShape !== 'object' || globalObjectShape === null;
     if (shouldUseDefaultGlobalOwnKeys && defaultGlobalOwnKeys === null) {
         defaultGlobalOwnKeys = filterWindowKeys(
-            getFilteredGlobalOwnKeys(redWindow, remapTypedArrays)
+            getFilteredGlobalOwnKeys(redWindow, remapTypedArrays),
+            remapTypedArrays
         );
     }
     let blueConnector = blueCreateHooksCallbackCache.get(blueRefs.document) as
@@ -145,7 +146,7 @@ function createIframeVirtualEnvironment(
         blueRefs.window,
         shouldUseDefaultGlobalOwnKeys
             ? (defaultGlobalOwnKeys as PropertyKey[])
-            : filterWindowKeys(getFilteredGlobalOwnKeys(globalObjectShape)),
+            : filterWindowKeys(getFilteredGlobalOwnKeys(globalObjectShape), remapTypedArrays),
         // Chromium based browsers have a bug that nulls the result of `window`
         // getters in detached iframes when the property descriptor of `window.window`
         // is retrieved.
@@ -159,7 +160,7 @@ function createIframeVirtualEnvironment(
             endowments,
             remapTypedArrays
         );
-        removeWindowDescriptors(filteredEndowments);
+        removeWindowDescriptors(filteredEndowments, remapTypedArrays);
         env.remapProperties(blueRefs.window, filteredEndowments);
     }
     // We intentionally skip remapping Window.prototype because there is nothing
diff --git a/packages/near-membrane-dom/src/window.ts b/packages/near-membrane-dom/src/window.ts
index d8e6c071..bdbc220c 100644
--- a/packages/near-membrane-dom/src/window.ts
+++ b/packages/near-membrane-dom/src/window.ts
@@ -2,6 +2,7 @@ import {
     ReflectDeleteProperty,
     ReflectGetPrototypeOf,
     ReflectOwnKeys,
+    toSafeArray,
     toSafeWeakMap,
 } from '@locker/near-membrane-shared';
 import { IS_CHROMIUM_BROWSER, rootWindow } from '@locker/near-membrane-shared-dom';
@@ -62,8 +63,8 @@ export function getCachedGlobalObjectReferences(
     return record;
 }
 
-export function filterWindowKeys(keys: PropertyKey[]): PropertyKey[] {
-    const result: PropertyKey[] = [];
+export function filterWindowKeys(keys: PropertyKey[], remapTypedArrays: boolean): PropertyKey[] {
+    const result: PropertyKey[] = toSafeArray([]);
     let resultOffset = 0;
     for (let i = 0, { length } = keys; i < length; i += 1) {
         const key = keys[i];
@@ -79,6 +80,12 @@ export function filterWindowKeys(keys: PropertyKey[]): PropertyKey[] {
             result[resultOffset++] = key;
         }
     }
+
+    // Crypto and typed arrays must be from the same global object
+    if (remapTypedArrays === false) {
+        result.splice(result.indexOf('Crypto'), 1);
+    }
+
     return result;
 }
 
@@ -109,7 +116,10 @@ export function filterWindowKeys(keys: PropertyKey[]): PropertyKey[] {
  * that will be installed (via the membrane) as global descriptors in
  * the red realm.
  */
-export function removeWindowDescriptors<T extends PropertyDescriptorMap>(unsafeDescs: T): T {
+export function removeWindowDescriptors<T extends PropertyDescriptorMap>(
+    unsafeDescs: T,
+    remapTypedArrays: boolean
+): T {
     // Remove unforgeable descriptors that cannot be installed.
     ReflectDeleteProperty(unsafeDescs, 'document');
     ReflectDeleteProperty(unsafeDescs, 'location');
@@ -117,6 +127,10 @@ export function removeWindowDescriptors<T extends PropertyDescriptorMap>(unsafeD
     ReflectDeleteProperty(unsafeDescs, 'window');
     // Remove other browser specific unforgeables.
     ReflectDeleteProperty(unsafeDescs, 'chrome');
+    // Crypto and typed arrays must be from the same global object
+    if (remapTypedArrays === false) {
+        ReflectDeleteProperty(unsafeDescs, 'Crypto');
+    }
     return unsafeDescs;
 }
 
diff --git a/test/membrane/binary-data.spec.js b/test/membrane/binary-data.spec.js
index 9c6a639d..a8ff4af4 100644
--- a/test/membrane/binary-data.spec.js
+++ b/test/membrane/binary-data.spec.js
@@ -48,6 +48,30 @@ describe('Crypto', () => {
             endowments: Object.getOwnPropertyDescriptors({ expect }),
         });
 
+        env.evaluate(`
+            expect(() => {
+                crypto.getRandomValues(new Uint8Array(1));
+            }).not.toThrow();
+        `);
+    });
+    it('works when typed arrays are not remapped', () => {
+        const env = createVirtualEnvironment(window, {
+            endowments: Object.getOwnPropertyDescriptors({ expect }),
+            remapTypedArrays: false,
+        });
+
+        env.evaluate(`
+            expect(() => {
+                crypto.getRandomValues(new Uint8Array(1));
+            }).not.toThrow();
+        `);
+    });
+    it('ignores the presense of crypto in endowments if remapTypedArrays is false', () => {
+        const env = createVirtualEnvironment(window, {
+            endowments: Object.getOwnPropertyDescriptors({ Crypto, crypto, expect }),
+            remapTypedArrays: false,
+        });
+
         env.evaluate(`
             expect(() => {
                 crypto.getRandomValues(new Uint8Array(1));