README.md

@@ -2175,14 +2175,17 @@ view would leave a wallet one click from deletion.
   code `4100` and opens no prompt. Two such origins are `null`, which the
   browser reports for a page with an opaque origin, such as one its server
   sandboxes with a Content-Security-Policy, and `file://`, which Chrome reports
-  for a local file. The background script prefers the toolbar popup
-  (`action.openPopup()`) and falls back to a separate popup window
-  (`src/background/index.js`, `requestApproval()`). Only one exists per site at
-  a time: a further connection request from a site whose prompt is still
-  unanswered is refused with EIP-1193 code `-32002` and opens no new prompt. If
-  that prompt was in a toolbar popup that closed before it connected, and the
-  toolbar popup has since been set to open something else, the refused request
-  shows that prompt again.
+  for a local file. Nor is such a page told the active address by
+  `accountsChanged`, even at a connected site's URL: the background names the
+  origin of the tab's URL on the event, and the content script passes the
+  address on only to a page whose own origin is that one. The background script
+  prefers the toolbar popup (`action.openPopup()`) and falls back to a separate
+  popup window (`src/background/index.js`, `requestApproval()`). Only one exists
+  per site at a time: a further connection request from a site whose prompt is
+  still unanswered is refused with EIP-1193 code `-32002` and opens no new
+  prompt. If that prompt was in a toolbar popup that closed before it connected,
+  and the toolbar popup has since been set to open something else, the refused
+  request shows that prompt again.
 - **Elements**:
     - "Connection Request" heading
     - Phishing warning banner (shown when the hostname is on the phishing

src/background/index.js

@@ -1308,6 +1308,12 @@ async function broadcastAccountsChanged() {
         return;
     }
     for (const tab of tabs) {
+        // The tab's URL is all the background knows of the page in it, and a
+        // page at a site's URL may have another origin: a page its server
+        // sandboxes with a Content-Security-Policy has the origin "null". So
+        // the event names the origin it was judged by, and the content script
+        // passes the address on only to a page whose own origin is that one
+        // (src/content/index.js).
         const origin = tab.url ? new URL(tab.url).origin : "";
         const hasPermission =
             activeAddress &&
@@ -1319,6 +1325,7 @@ async function broadcastAccountsChanged() {
             type: "AUTISTMASK_EVENT",
             eventName: "accountsChanged",
             data: hasPermission ? [activeAddress] : [],
+            origin,
         }).catch(() => {});
     }
 }

src/content/index.js

@@ -49,14 +49,23 @@ window.addEventListener("message", (event) => {
 
 // Listen for events pushed from the background (e.g. accountsChanged)
 runtimeApi().onMessage.addListener((msg) => {
-    if (msg.type === "AUTISTMASK_EVENT") {
-        window.postMessage(
-            {
-                type: "AUTISTMASK_EVENT",
-                eventName: msg.eventName,
-                data: msg.data,
-            },
-            "*",
-        );
+    if (msg.type !== "AUTISTMASK_EVENT") return;
+    // The background chooses the addresses in accountsChanged for the site
+    // at the origin the event names, which is the origin of the tab's URL.
+    // This page hears them only when its own origin is that one. A page whose
+    // origin has no host is not a site: one its server sandboxes with a
+    // Content-Security-Policy has the origin "null" whatever its URL, and is
+    // told no address, as its requests are refused.
+    let data = msg.data;
+    if (msg.eventName === "accountsChanged" && msg.origin !== window.origin) {
+        data = [];
     }
+    window.postMessage(
+        {
+            type: "AUTISTMASK_EVENT",
+            eventName: msg.eventName,
+            data,
+        },
+        "*",
+    );
 });

tests/accountsChangedOpaqueOrigin.test.js

@@ -0,0 +1,167 @@
+// A page whose origin has no host is never told an address by accountsChanged
+// (https://git.eeqj.de/sneak/AutistMask/issues/564).
+//
+// When the user switches address, the background tells each open tab the new
+// active address if the site at the tab's URL is connected. A page at a
+// connected site's URL can still have another origin: one its server
+// sandboxes with a Content-Security-Policy has the origin "null", and every
+// request it makes is refused. Each test here switches the address in the real
+// background, takes the event it sent to a tab at the site's URL, and hands
+// that event to the real content script in a page of the given origin.
+
+const { networkById } = require("../src/shared/networks");
+const { makeStorageStub } = require("./support/storageStub");
+
+const ADDRESS = "0x66133E8ea0f5D1d612D2502a968757D1048c214a";
+const SITE = "https://dapp.example";
+
+const EXT_URL = "chrome-extension://autistmask/";
+const FROM_POPUP = { url: EXT_URL + "src/popup/index.html" };
+
+// One address, with SITE remembered as allowed for it.
+function storedProfile() {
+    const mainnet = networkById("mainnet");
+    return {
+        hasWallet: true,
+        wallets: [
+            {
+                name: "Wallet 1",
+                type: "hd",
+                addresses: [
+                    { address: ADDRESS, balance: "0", tokenBalances: [] },
+                ],
+            },
+        ],
+        activeAddress: ADDRESS,
+        networkId: "mainnet",
+        rpcUrl: mainnet.defaultRpcUrl,
+        blockscoutUrl: mainnet.defaultBlockscoutUrl,
+        allowedSites: { [ADDRESS]: [SITE] },
+        deniedSites: {},
+        trackedTokens: [],
+    };
+}
+
+async function settle() {
+    for (let i = 0; i < 50; i++) await Promise.resolve();
+}
+
+afterEach(() => {
+    delete global.chrome;
+    delete global.window;
+    jest.resetModules();
+});
+
+// The popup tells the background the active address changed, and the one
+// open tab, at SITE's URL, is sent an event. That event is returned.
+async function eventSentToSiteTab() {
+    jest.resetModules();
+    jest.doMock("../src/shared/balances", () => ({
+        getProvider: () => ({}),
+        refreshBalances: jest.fn(async () => {}),
+    }));
+    jest.doMock("../src/shared/phishingDomains", () => ({
+        isPhishingDomain: () => false,
+    }));
+    jest.doMock("../src/shared/alarms", () => ({
+        BALANCE_REFRESH_ALARM: "balance",
+        BALANCE_REFRESH_PERIOD_MINUTES: 1,
+        ensureRecurringAlarms: jest.fn(async () => {}),
+        registerAlarmHandlers: jest.fn(),
+    }));
+
+    let messageListener = null;
+    const sentToTabs = [];
+    global.chrome = {
+        storage: makeStorageStub({ autistmask: storedProfile() }),
+        runtime: {
+            getURL: (path) => EXT_URL + path,
+            onMessage: {
+                addListener: (fn) => {
+                    messageListener = fn;
+                },
+            },
+            onConnect: { addListener: () => {} },
+            getPlatformInfo: (cb) => cb({ os: "linux" }),
+            lastError: null,
+        },
+        windows: {
+            remove: (id, cb) => {
+                if (cb) cb();
+            },
+            onRemoved: { addListener: () => {} },
+        },
+        tabs: {
+            query: (q, cb) => cb([{ id: 1, url: SITE + "/app" }]),
+            sendMessage: (tabId, msg, cb) => {
+                sentToTabs.push(msg);
+                if (cb) cb();
+            },
+        },
+        action: { setPopup: () => {} },
+    };
+
+    require("../src/background/index");
+    messageListener(
+        { type: "AUTISTMASK_ACTIVE_CHANGED" },
+        FROM_POPUP,
+        () => {},
+    );
+    await settle();
+
+    expect(sentToTabs).toHaveLength(1);
+    return sentToTabs[0];
+}
+
+// The content script in a page whose origin is `pageOrigin` is handed `event`
+// from the background. What it posts to the page is returned.
+function postedToPage(event, pageOrigin) {
+    jest.resetModules();
+    let eventListener = null;
+    const posted = [];
+    global.chrome = {
+        runtime: {
+            onMessage: {
+                addListener: (fn) => {
+                    eventListener = fn;
+                },
+            },
+        },
+    };
+    global.window = {
+        origin: pageOrigin,
+        addEventListener: () => {},
+        postMessage: (data) => posted.push(data),
+    };
+
+    require("../src/content/index");
+    eventListener(event);
+
+    return posted;
+}
+
+describe("accountsChanged after an address switch, at a connected site's URL", () => {
+    test("the site's own page is told the active address", async () => {
+        const event = await eventSentToSiteTab();
+
+        expect(postedToPage(event, SITE)).toEqual([
+            {
+                type: "AUTISTMASK_EVENT",
+                eventName: "accountsChanged",
+                data: [ADDRESS],
+            },
+        ]);
+    });
+
+    test("a page whose origin has no host is told no address", async () => {
+        const event = await eventSentToSiteTab();
+
+        expect(postedToPage(event, "null")).toEqual([
+            {
+                type: "AUTISTMASK_EVENT",
+                eventName: "accountsChanged",
+                data: [],
+            },
+        ]);
+    });
+});