Updating extension for ppom-validator updates (#20000)

.metamaskrc.dist

@@ -12,3 +12,4 @@ INFURA_PROJECT_ID=00000000000
 
 ; Set this to test changes to the phishing warning page.
 ;PHISHING_WARNING_PAGE_URL=
+BLOCKAID_FILE_CDN=

app/scripts/lib/ppom/ppom-middleware.test.ts

@@ -0,0 +1,110 @@
+import { createPPOMMiddleware } from './ppom-middleware';
+
+Object.defineProperty(globalThis, 'fetch', {
+  writable: true,
+  value: () => undefined,
+});
+
+Object.defineProperty(globalThis, 'performance', {
+  writable: true,
+  value: () => undefined,
+});
+
+describe('PPOMMiddleware', () => {
+  it('should call ppomController.usePPOM for requests of type confirmation', async () => {
+    const useMock = jest.fn();
+    const controller = {
+      usePPOM: useMock,
+    };
+    const middlewareFunction = createPPOMMiddleware(controller as any);
+    await middlewareFunction(
+      { method: 'eth_sendTransaction' },
+      undefined,
+      () => undefined,
+    );
+    expect(useMock).toHaveBeenCalledTimes(1);
+  });
+
+  it('should add validation response on confirmation requests', async () => {
+    const controller = {
+      usePPOM: async () => Promise.resolve('VALIDATION_RESULT'),
+    };
+    const middlewareFunction = createPPOMMiddleware(controller as any);
+    const req = { method: 'eth_sendTransaction', ppomResponse: undefined };
+    await middlewareFunction(req, undefined, () => undefined);
+    expect(req.ppomResponse).toBeDefined();
+  });
+
+  it('should call next method when ppomController.usePPOM completes', async () => {
+    const ppom = {
+      validateJsonRpc: () => undefined,
+    };
+    const controller = {
+      usePPOM: async (callback: any) => {
+        callback(ppom);
+      },
+    };
+    const middlewareFunction = createPPOMMiddleware(controller as any);
+    const nextMock = jest.fn();
+    await middlewareFunction(
+      { method: 'eth_sendTransaction' },
+      undefined,
+      nextMock,
+    );
+    expect(nextMock).toHaveBeenCalledTimes(1);
+  });
+
+  it('should call next method when ppomController.usePPOM throws error', async () => {
+    const controller = {
+      usePPOM: async (_callback: any) => {
+        throw Error('Some error');
+      },
+    };
+    const middlewareFunction = createPPOMMiddleware(controller as any);
+    const nextMock = jest.fn();
+    await middlewareFunction(
+      { method: 'eth_sendTransaction' },
+      undefined,
+      nextMock,
+    );
+    expect(nextMock).toHaveBeenCalledTimes(1);
+  });
+
+  it('should call ppom.validateJsonRpc when invoked', async () => {
+    const validateMock = jest.fn();
+    const ppom = {
+      validateJsonRpc: validateMock,
+    };
+    const controller = {
+      usePPOM: async (callback: any) => {
+        callback(ppom);
+      },
+    };
+    const middlewareFunction = createPPOMMiddleware(controller as any);
+    await middlewareFunction(
+      { method: 'eth_sendTransaction' },
+      undefined,
+      () => undefined,
+    );
+    expect(validateMock).toHaveBeenCalledTimes(1);
+  });
+
+  it('should not call ppom.validateJsonRpc when request is not for confirmation method', async () => {
+    const validateMock = jest.fn();
+    const ppom = {
+      validateJsonRpc: validateMock,
+    };
+    const controller = {
+      usePPOM: async (callback: any) => {
+        callback(ppom);
+      },
+    };
+    const middlewareFunction = createPPOMMiddleware(controller as any);
+    await middlewareFunction(
+      { method: 'eth_someRequest' },
+      undefined,
+      () => undefined,
+    );
+    expect(validateMock).toHaveBeenCalledTimes(0);
+  });
+});

app/scripts/lib/ppom/ppom-middleware.ts

@@ -0,0 +1,43 @@
+import { PPOM } from '@blockaid/ppom';
+
+import { PPOMController } from '@metamask/ppom-validator';
+
+const ConfirmationMethods = Object.freeze([
+  'eth_sendRawTransaction',
+  'eth_sendTransaction',
+  'eth_sign',
+  'eth_signTypedData',
+  'eth_signTypedData_v1',
+  'eth_signTypedData_v3',
+  'eth_signTypedData_v4',
+  'personal_sign',
+]);
+
+/**
+ * Middleware function that handles JSON RPC requests.
+ * This function will be called for every JSON RPC request.
+ * It will call the PPOM to check if the request is malicious or benign.
+ * If the request is benign, it will be forwarded to the next middleware.
+ * If the request is malicious or warning, it will trigger the PPOM alert dialog,
+ * after the user has confirmed or rejected the request,
+ * the request will be forwarded to the next middleware, together with the PPOM response.
+ *
+ * @param ppomController - Instance of PPOMController.
+ * @returns PPOMMiddleware function.
+ */
+export function createPPOMMiddleware(ppomController: PPOMController) {
+  return async (req: any, _res: any, next: () => void) => {
+    try {
+      if (ConfirmationMethods.includes(req.method)) {
+        // eslint-disable-next-line require-atomic-updates
+        req.ppomResponse = await ppomController.usePPOM(async (ppom: PPOM) => {
+          return ppom.validateJsonRpc(req);
+        });
+      }
+    } catch (error: unknown) {
+      console.error('Error validating JSON RPC using PPOM: ', error);
+    } finally {
+      next();
+    }
+  };
+}