completed replay attack demonstrator example

typescript/replay-attack-demonstrator-example/app.test.ts

@@ -0,0 +1,134 @@
+import { ethers } from 'ethers';
+import {
+  createTransaction,
+  serializeTransaction,
+  canReplayTransaction,
+  getTransactionDetails,
+  NETWORKS
+} from './app';
+
+describe('Replay Attack Demonstrator', () => {
+  describe('createTransaction', () => {
+    it('should create a transaction with correct parameters', () => {
+      const tx = createTransaction(
+        '0x2222222222222222222222222222222222222222',
+        '1.0',
+        56,
+        0,
+        '21000',
+        '20000000000'
+      );
+
+      expect(tx.to).toBe('0x2222222222222222222222222222222222222222');
+      expect(tx.value).toBe(ethers.parseEther('1.0'));
+      expect(tx.chainId).toBe(56);
+      expect(tx.nonce).toBe(0);
+      expect(tx.gasLimit).toBe('21000');
+      expect(tx.gasPrice).toBe('20000000000');
+      expect(tx.type).toBe(0);
+    });
+
+    it('should use default values when optional parameters are not provided', () => {
+      const tx = createTransaction(
+        '0x2222222222222222222222222222222222222222',
+        '0.5',
+        97
+      );
+
+      expect(tx.nonce).toBe(0);
+      expect(tx.gasLimit).toBe('21000');
+      expect(tx.gasPrice).toBe('20000000000');
+    });
+  });
+
+  describe('serializeTransaction', () => {
+    it('should serialize a signed transaction hex string', async () => {
+      // Create a mock signed transaction hex
+      const wallet = ethers.Wallet.createRandom();
+      const tx = createTransaction(
+        '0x2222222222222222222222222222222222222222',
+        '0.1',
+        56
+      );
+
+      // This will create a signed transaction
+      const signedTx = await wallet.signTransaction(tx);
+      const parsed = serializeTransaction(signedTx);
+      expect(parsed).toBeInstanceOf(ethers.Transaction);
+      expect(parsed.to).toBe('0x2222222222222222222222222222222222222222');
+    });
+  });
+
+  describe('canReplayTransaction', () => {
+    it('should detect that transaction with chainId protection cannot be replayed on different network', async () => {
+      const wallet = ethers.Wallet.createRandom();
+      const tx = createTransaction(
+        '0x2222222222222222222222222222222222222222',
+        '0.1',
+        56 // BSC Mainnet
+      );
+
+      const signedTx = await wallet.signTransaction(tx);
+      const parsed = serializeTransaction(signedTx);
+
+      const result = canReplayTransaction(56, 1, parsed); // Try to replay on Ethereum Mainnet
+
+      expect(result.canReplay).toBe(false);
+      expect(result.reason).toContain('protected by chainId');
+    });
+
+    it('should detect that transaction can be replayed on same network', async () => {
+      const wallet = ethers.Wallet.createRandom();
+      const tx = createTransaction(
+        '0x2222222222222222222222222222222222222222',
+        '0.1',
+        56 // BSC Mainnet
+      );
+
+      const signedTx = await wallet.signTransaction(tx);
+      const parsed = serializeTransaction(signedTx);
+
+      const result = canReplayTransaction(56, 56, parsed); // Same network
+
+      expect(result.canReplay).toBe(true);
+      expect(result.reason).toContain('matches target network');
+    });
+  });
+
+  describe('getTransactionDetails', () => {
+    it('should extract transaction details from signed transaction hex', async () => {
+      const wallet = ethers.Wallet.createRandom();
+      const tx = createTransaction(
+        '0x2222222222222222222222222222222222222222',
+        '0.5',
+        56
+      );
+
+      const signedTx = await wallet.signTransaction(tx);
+      const details = getTransactionDetails(signedTx);
+
+      expect(details.transaction).toBeInstanceOf(ethers.Transaction);
+      expect(details.to).toBe('0x2222222222222222222222222222222222222222');
+      expect(details.value).toBe('0.5');
+      expect(details.chainId).toBe(56);
+      expect(details.from).toBeDefined();
+    });
+  });
+
+  describe('NETWORKS', () => {
+    it('should have correct network configurations', () => {
+      expect(NETWORKS['bsc-mainnet']).toBeDefined();
+      expect(NETWORKS['bsc-mainnet'].chainId).toBe(56);
+      expect(NETWORKS['bsc-mainnet'].name).toBe('BSC Mainnet');
+
+      expect(NETWORKS['bsc-testnet']).toBeDefined();
+      expect(NETWORKS['bsc-testnet'].chainId).toBe(97);
+
+      expect(NETWORKS['eth-mainnet']).toBeDefined();
+      expect(NETWORKS['eth-mainnet'].chainId).toBe(1);
+
+      expect(NETWORKS['eth-sepolia']).toBeDefined();
+      expect(NETWORKS['eth-sepolia'].chainId).toBe(11155111);
+    });
+  });
+});