tokenbridge: implement new governance packet spec

Change-Id: Iee4b596b6a8ca9dfc9c6ee8c6188a4083a05edeb

ethereum/contracts/bridge/BridgeGovernance.sol

@@ -20,17 +20,21 @@ import "../interfaces/IWormhole.sol";
 contract BridgeGovernance is BridgeGetters, BridgeSetters, ERC1967Upgrade {
     using BytesLib for bytes;
 
+    // "TokenBridge" (left padded)
+    bytes32 constant module = 0x000000000000000000000000000000000000000000546f6b656e427269646765;
+
     // Execute a RegisterChain governance message
     function registerChain(bytes memory encodedVM) public {
         (IWormhole.VM memory vm, bool valid, string memory reason) = verifyGovernanceVM(encodedVM);
         require(valid, reason);
 
-
         setGovernanceActionConsumed(vm.hash);
 
         BridgeStructs.RegisterChain memory chain = parseRegisterChain(vm.payload);
 
-        setBridgeImplementation(chain.chainID, chain.emitterAddress);
+        require(chain.chainId == chainId() || chain.chainId == 0, "invalid chain id");
+
+        setBridgeImplementation(chain.emitterChainID, chain.emitterAddress);
     }
 
     // Execute a UpgradeContract governance message
@@ -42,7 +46,7 @@ contract BridgeGovernance is BridgeGetters, BridgeSetters, ERC1967Upgrade {
 
         BridgeStructs.UpgradeContract memory implementation = parseUpgrade(vm.payload);
 
-        require(implementation.chainID == chainId(), "wrong chain id");
+        require(implementation.chainId == chainId(), "wrong chain id");
 
         upgradeImplementation(address(uint160(uint256(implementation.newContract))));
     }
@@ -85,34 +89,51 @@ contract BridgeGovernance is BridgeGetters, BridgeSetters, ERC1967Upgrade {
     function parseRegisterChain(bytes memory encoded) public pure returns(BridgeStructs.RegisterChain memory chain) {
         uint index = 0;
 
-        chain.payloadID = encoded.toUint8(index);
+        // governance header
+
+        chain.module = encoded.toBytes32(index);
+        index += 32;
+        require(chain.module == module, "invalid RegisterChain: wrong module");
+
+        chain.action = encoded.toUint8(index);
         index += 1;
+        require(chain.action == 1, "invalid RegisterChain: wrong action");
 
-        require(chain.payloadID == 3, "invalid RegisterChain");
+        chain.chainId = encoded.toUint16(index);
+        index += 2;
 
-        chain.chainID = encoded.toUint16(index);
+        // payload
+
+        chain.emitterChainID = encoded.toUint16(index);
         index += 2;
 
         chain.emitterAddress = encoded.toBytes32(index);
         index += 32;
 
-        require(encoded.length == index, "invalid RegisterChain");
+        require(encoded.length == index, "invalid RegisterChain: wrong length");
     }
 
     function parseUpgrade(bytes memory encoded) public pure returns(BridgeStructs.UpgradeContract memory chain) {
         uint index = 0;
 
-        chain.payloadID = encoded.toUint8(index);
+        // governance header
+
+        chain.module = encoded.toBytes32(index);
+        index += 32;
+        require(chain.module == module, "invalid UpgradeContract: wrong module");
+
+        chain.action = encoded.toUint8(index);
         index += 1;
+        require(chain.action == 2, "invalid UpgradeContract: wrong action");
 
-        require(chain.payloadID == 4, "invalid UpgradeContract");
+        chain.chainId = encoded.toUint16(index);
-
-        chain.chainID = encoded.toUint16(index);
         index += 2;
 
+        // payload
+
         chain.newContract = encoded.toBytes32(index);
         index += 32;
 
-        require(encoded.length == index, "invalid UpgradeContract");
+        require(encoded.length == index, "invalid UpgradeContract: wrong length");
     }
 }

ethereum/contracts/bridge/BridgeStructs.sol

@@ -37,19 +37,29 @@ contract BridgeStructs {
     }
 
     struct RegisterChain {
-        // PayloadID uint8 = 3
+        // Governance Header
-        uint8 payloadID;
+        // module: "TokenBridge" left-padded
+        bytes32 module;
+        // governance action: 1
+        uint8 action;
+        // governance paket chain id: this or 0
+        uint16 chainId;
+
         // Chain ID
-        uint16 chainID;
+        uint16 emitterChainID;
         // Emitter address. Left-zero-padded if shorter than 32 bytes
         bytes32 emitterAddress;
     }
 
     struct UpgradeContract {
-        // PayloadID uint8 = 4
+        // Governance Header
-        uint8 payloadID;
+        // module: "TokenBridge" left-padded
-        // Chain ID
+        bytes32 module;
-        uint16 chainID;
+        // governance action: 2
+        uint8 action;
+        // governance paket chain id
+        uint16 chainId;
+
         // Address of the new contract
         bytes32 newContract;
     }

ethereum/test/bridge.js

@@ -79,7 +79,10 @@ contract("Bridge", function () {
         const accounts = await web3.eth.getAccounts();
 
         let data = [
-            "0x03",
+            "0x",
+            "000000000000000000000000000000000000000000546f6b656e427269646765",
+            "01",
+            "0000",
             web3.eth.abi.encodeParameter("uint16", testForeignChainId).substring(2 + (64 - 4)),
             web3.eth.abi.encodeParameter("bytes32", testForeignBridgeContract).substring(2),
         ].join('')
@@ -121,7 +124,9 @@ contract("Bridge", function () {
         const mock = await MockBridgeImplementation.new();
 
         let data = [
-            "0x04",
+            "0x",
+            "000000000000000000000000000000000000000000546f6b656e427269646765",
+            "02",
             web3.eth.abi.encodeParameter("uint16", testChainId).substring(2 + (64 - 4)),
             web3.eth.abi.encodeParameter("address", mock.address).substring(2),
         ].join('')