Add messenger proxy (#53)

* Started proxy bridge

* Fix L1MessengerProxy deploy

* Attempt 2

* Fix bug in ResolvedDelegateProxy

* Fix bug in L1XDomainMessenger

* Reduce nodes in Merkle Trie tests

* Fix rebase error

* Add clarifying comment to delegate proxy
Co-authored-by: Kelvin Fichter <kelvinfichter@gmail.com>

packages/contracts/contracts/optimistic-ethereum/OVM/bridge/OVM_L1CrossDomainMessenger.sol

@@ -5,6 +5,7 @@ pragma experimental ABIEncoderV2;
 /* Library Imports */
 import { Lib_OVMCodec } from "../../libraries/codec/Lib_OVMCodec.sol";
 import { Lib_AddressResolver } from "../../libraries/resolver/Lib_AddressResolver.sol";
+import { Lib_AddressManager } from "../../libraries/resolver/Lib_AddressManager.sol";
 import { Lib_SecureMerkleTrie } from "../../libraries/trie/Lib_SecureMerkleTrie.sol";
 
 /* Interface Imports */
@@ -24,12 +25,24 @@ contract OVM_L1CrossDomainMessenger is iOVM_L1CrossDomainMessenger, OVM_BaseCros
      * Constructor *
      ***************/
 
+    /**
+     * Pass a default zero address to the address resolver. This will be updated when initialized.
+     */
+    constructor()
+        Lib_AddressResolver(address(0))
+    {}
+
     /**
      * @param _libAddressManager Address of the Address Manager.
      */
-    constructor(
+    function initialize(
         address _libAddressManager
-    ) Lib_AddressResolver(_libAddressManager) {}
+    )
+        public
+    {
+        require(address(libAddressManager) == address(0), "L1CrossDomainMessenger already intialized.");
+        libAddressManager = Lib_AddressManager(_libAddressManager);
+    }
 
 
     /********************

packages/contracts/contracts/optimistic-ethereum/libraries/resolver/Lib_ResolvedDelegateProxy.sol

+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.7.0;
+
+/* Library Imports */
+import { Lib_AddressManager } from "./Lib_AddressManager.sol";
+
+/**
+ * @title Lib_ResolvedDelegateProxy
+ */
+contract Lib_ResolvedDelegateProxy {
+
+    /*************
+     * Variables *
+     *************/
+
+    // Using mappings to store fields to avoid overwriting storage slots in the
+    // implementation contract. For example, instead of storing these fields at
+    // storage slot `0` & `1`, they are stored at `hash(${FIELD_NAME} + address(this))`
+    // See: https://solidity.readthedocs.io/en/v0.7.0/internals/layout_in_storage.html
+    mapping(address=>string) private implementationName;
+    mapping(address=>Lib_AddressManager) private addressManager;
+
+
+    /***************
+     * Constructor *
+     ***************/
+
+    /**
+     * @param _libAddressManager Address of the Lib_AddressManager.
+     * @param _implementationName implementationName of the contract to proxy to.
+     */
+    constructor(
+        address _libAddressManager,
+        string memory _implementationName
+    )
+    {
+        addressManager[address(this)] = Lib_AddressManager(_libAddressManager);
+        implementationName[address(this)] = _implementationName;
+    }
+
+
+    /*********************
+     * Fallback Function *
+     *********************/
+
+    fallback()
+        external
+    {
+        address target = addressManager[address(this)].getAddress((implementationName[address(this)]));
+        require(
+            target != address(0),
+            "Target address must be initialized."
+        );
+
+        (bool success, bytes memory returndata) = target.delegatecall(msg.data);
+
+        if (success == true) {
+            assembly {
+                return(add(returndata, 0x20), mload(returndata))
+            }
+        } else {
+            assembly {
+                revert(add(returndata, 0x20), mload(returndata))
+            }
+        }
+    }
+}

packages/contracts/src/contract-deployment/config.ts

@@ -43,7 +43,17 @@ export const makeContractDeployConfig = async (
   return {
     OVM_L1CrossDomainMessenger: {
       factory: getContractFactory('OVM_L1CrossDomainMessenger'),
-      params: [AddressManager.address],
+      params: [],
+    },
+    Proxy__OVM_L1CrossDomainMessenger: {
+      factory: getContractFactory('Lib_ResolvedDelegateProxy'),
+      params: [AddressManager.address, 'OVM_L1CrossDomainMessenger'],
+      afterDeploy: async (contracts): Promise<void> => {
+        const xDomainMessenger = getContractFactory(
+          'OVM_L1CrossDomainMessenger'
+        ).attach(contracts.Proxy__Proxy__OVM_L1CrossDomainMessenger.address)
+        await xDomainMessenger.initialize(AddressManager.address)
+      },
     },
     OVM_L2CrossDomainMessenger: {
       factory: getContractFactory('OVM_L2CrossDomainMessenger'),

packages/contracts/test/contracts/OVM/bridge/OVM_L1CrossDomainMessenger.spec.ts

@@ -34,6 +34,20 @@ const getXDomainCalldata = (
   ).encodeFunctionData('relayMessage', [target, sender, message, messageNonce])
 }
 
+const deployProxyXDomainMessenger = async (
+  addressManager: Contract,
+  l1XDomainMessenger: Contract
+): Promise<Contract> => {
+  await addressManager.setAddress(
+    'OVM_L1CrossDomainMessenger',
+    l1XDomainMessenger.address
+  )
+  const proxy = await (await ethers.getContractFactory(
+      'Lib_ResolvedDelegateProxy'
+  )).deploy(addressManager.address, 'OVM_L1CrossDomainMessenger')
+  return l1XDomainMessenger.attach(proxy.address)
+}
+
 describe('OVM_L1CrossDomainMessenger', () => {
   let signer: Signer
   before(async () => {
@@ -89,9 +103,10 @@ describe('OVM_L1CrossDomainMessenger', () => {
 
   let OVM_L1CrossDomainMessenger: Contract
   beforeEach(async () => {
-    OVM_L1CrossDomainMessenger = await Factory__OVM_L1CrossDomainMessenger.deploy(
-      AddressManager.address
-    )
+    const xDomainMessenerImpl = await Factory__OVM_L1CrossDomainMessenger.deploy()
+    // We use an upgradable proxy for the XDomainMessenger--deploy & set up the proxy.
+    OVM_L1CrossDomainMessenger = await deployProxyXDomainMessenger(AddressManager, xDomainMessenerImpl)
+    await OVM_L1CrossDomainMessenger.initialize(AddressManager.address)
   })
 
   describe('sendMessage', () => {

packages/contracts/test/contracts/libraries/trie/Lib_MerkleTrie.spec.ts

@@ -7,7 +7,7 @@ import { Contract } from 'ethers'
 /* Internal Imports */
 import { TrieTestGenerator } from '../../../helpers'
 
-const NODE_COUNTS = [1, 2, 128, 256, 512, 1024, 2048, 4096]
+const NODE_COUNTS = [1, 2, 128]
 
 describe('Lib_MerkleTrie', () => {
   let Lib_MerkleTrie: Contract

packages/contracts/test/contracts/libraries/trie/Lib_SecureMerkleTrie.spec.ts

@@ -7,7 +7,7 @@ import { Contract } from 'ethers'
 /* Internal Imports */
 import { TrieTestGenerator } from '../../../helpers'
 
-const NODE_COUNTS = [1, 2, 128, 256, 512, 1024, 2048, 4096]
+const NODE_COUNTS = [1, 2, 128]
 
 describe('Lib_SecureMerkleTrie', () => {
   let Lib_SecureMerkleTrie: Contract