feat: overwrite WebRTC APIs with a recursive ES6 proxy (#141)

* feat: overwrite webrtc APIs with a recursive ES6 proxy * feat: add webrtc option to FingerprintOptions * feat: simplify mockWebRTC interface * chore: add webRTC mocking tests
apify · Sep 27, 2023 · 3c5c675 · 3c5c675
1 parent e081c5d
commit 3c5c675
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Showing 4 changed files with 107 additions and 3 deletions.
diff --git a/packages/fingerprint-generator/src/fingerprint-generator.ts b/packages/fingerprint-generator/src/fingerprint-generator.ts
@@ -61,6 +61,7 @@ export type Fingerprint = {
     videoCard: VideoCard;
     multimediaDevices: string[];
     fonts: string[];
+    mockWebRTC: boolean;
 }
 
 export type BrowserFingerprintWithHeaders = {
@@ -79,6 +80,7 @@ export interface FingerprintGeneratorOptions extends HeaderGeneratorOptions {
         minHeight?: number;
         maxHeight?: number;
     };
+    mockWebRTC?: boolean;
 }
 
 /**
@@ -95,6 +97,7 @@ export class FingerprintGenerator extends HeaderGenerator {
         super(options);
         this.fingerprintGlobalOptions = {
             screen: options.screen,
+            mockWebRTC: options.mockWebRTC,
         };
         this.fingerprintGeneratorNetwork = new BayesianNetwork({ path: `${__dirname}/data_files/fingerprint-network-definition.zip` });
     }
@@ -174,7 +177,10 @@ export class FingerprintGenerator extends HeaderGenerator {
             fingerprint.languages = acceptedLanguages;
 
             return {
-                fingerprint: this.transformFingerprint(fingerprint),
+                fingerprint: {
+                    ...this.transformFingerprint(fingerprint),
+                    mockWebRTC: options.mockWebRTC ?? this.fingerprintGlobalOptions.mockWebRTC ?? false,
+                },
                 headers,
             };
         }

diff --git a/packages/fingerprint-injector/src/fingerprint-injector.ts b/packages/fingerprint-injector/src/fingerprint-injector.ts
@@ -18,6 +18,7 @@ declare function overrideWebGl(webGlInfo: Record<string, string>) : void;
 declare function overrideIntlAPI(language: string) : void;
 declare function overrideStatic() : void;
 declare function runHeadlessFixes() : void;
+declare function blockWebRTC() : void;
 
 /**
  * Fingerprint injector class.
@@ -157,6 +158,7 @@ export class FingerprintInjector {
                 historyLength,
                 audioCodecs,
                 videoCodecs,
+                mockWebRTC,
                 // @ts-expect-error internal browser code
             } = fp as EnhancedFingerprint;
 
@@ -198,6 +200,8 @@ export class FingerprintInjector {
 
             runHeadlessFixes();
 
+            if (mockWebRTC) blockWebRTC();
+
             overrideIntlAPI(navigatorProps.language);
             overrideStatic();
 

diff --git a/packages/fingerprint-injector/src/utils.js b/packages/fingerprint-injector/src/utils.js
@@ -451,6 +451,32 @@ function overrideDocumentDimensionsProps(props) {
     }
 }
 
+// Replaces all the WebRTC related methods with a recursive ES6 Proxy 
+// This way, we don't have to model a mock WebRTC API and we still don't get any exceptions.
+function blockWebRTC() {
+    const handler = {
+        get: () => {
+            return new Proxy(() => {}, handler);
+        },
+        apply: () => {
+            return new Proxy(() => {}, handler);
+        },
+        construct: () => {
+            return new Proxy(() => {}, handler);
+        },
+    };
+
+    const ConstrProxy = new Proxy(Object, handler);
+
+    navigator.mediaDevices.getUserMedia =
+    navigator.webkitGetUserMedia =
+    navigator.mozGetUserMedia =
+    navigator.getUserMedia =
+    window.webkitRTCPeerConnection = new Proxy(() => {}, handler);
+    MediaStreamTrack =
+    RTCPeerConnection = ConstrProxy;
+}
+
 // eslint-disable-next-line no-unused-vars
 function overrideUserAgentData(userAgentData) {
     try {

diff --git a/test/fingerprint-injector/fingerprint-injector.test.ts b/test/fingerprint-injector/fingerprint-injector.test.ts
@@ -1,5 +1,5 @@
-import playwright, { chromium } from 'playwright';
-import puppeteer from 'puppeteer';
+import playwright, { chromium, type Browser as PWBrowser } from 'playwright';
+import puppeteer, { Browser as PPBrowser } from 'puppeteer';
 import { BrowserFingerprintWithHeaders, Fingerprint, FingerprintGenerator } from 'fingerprint-generator';
 import { FingerprintInjector, newInjectedContext, newInjectedPage } from 'fingerprint-injector';
 
@@ -314,6 +314,74 @@ describe('FingerprintInjector', () => {
         });
     });
 
+    // @ts-expect-error test only
+    describe.each(cases)('%s', (frameworkName, testCases) => {
+        // @ts-expect-error test only
+        describe.each(testCases)('$name', ({ name, launcher, options, fingerprintGeneratorOptions }) => {
+            const fpg = new FingerprintGenerator(fingerprintGeneratorOptions);
+
+            const getNewPage = async (browser: PPBrowser | PWBrowser, fp: any): Promise<any> => {
+                if (frameworkName === 'Playwright') {
+                    const context = await (browser as PWBrowser).newContext();
+                    await fpInjector.attachFingerprintToPlaywright(context, fp);
+                    return context.newPage();
+                }
+                if (frameworkName === 'Puppeteer') {
+                    const page = await (browser as PPBrowser).newPage();
+                    await fpInjector.attachFingerprintToPuppeteer(page, fp);
+                    return page;
+                }
+                throw new Error(`Unknown framework name ${frameworkName}`);
+            };
+
+            test('WebRTC not blocked by default', async () => {
+                const fp = fpg.getFingerprint();
+
+                const browser = await launcher.launch({ ...options });
+                const page = await getNewPage(browser, fp);
+
+                await page.goto('https://hide.me/en/webrtc-leak-test');
+                await page.waitForTimeout(5000);
+                const ok = await page.$('.o-pagecheck__alert--ok');
+                expect(ok).toBeFalsy();
+
+                browser.close();
+            });
+
+            test('WebRTC not blocked if `mockWebRTC: false`', async () => {
+                const fp = fpg.getFingerprint({
+                    mockWebRTC: false,
+                });
+
+                const browser = await launcher.launch({ headless: false, ...options });
+                const page = await getNewPage(browser, fp);
+
+                await page.goto('https://hide.me/en/webrtc-leak-test');
+                await page.waitForTimeout(5000);
+                const ok = await page.$('.o-pagecheck__alert--ok');
+                expect(ok).toBeFalsy();
+
+                browser.close();
+            });
+
+            test('WebRTC blocked if `mockWebRTC: true`', async () => {
+                const fp = fpg.getFingerprint({
+                    mockWebRTC: true,
+                });
+
+                const browser = await launcher.launch({ headless: false, ...options });
+                const page = await getNewPage(browser, fp);
+
+                await page.goto('https://hide.me/en/webrtc-leak-test');
+                await page.waitForTimeout(5000);
+                const ok = await page.$('.o-pagecheck__alert--ok');
+                expect(ok).toBeTruthy();
+
+                browser.close();
+            });
+        });
+    });
+
     describe('helpers', () => {
         test('Playwright helpers', async () => {
             const browser = await chromium.launch();