core: vm: implement transfer node ownership (#255)

3 files changed, 83 insertions, 9 deletions

diff --git a/core/vm/oracle_contract_abi.go b/core/vm/oracle_contract_abi.go
index 23fb99ae5..e06adf633 100644
--- a/core/vm/oracle_contract_abi.go
+++ b/core/vm/oracle_contract_abi.go
@@ -741,7 +741,7 @@ const GovernanceABIJSON = `
     "constant": false,
     "inputs": [
       {
-        "name": "newOwner",
+        "name": "NewOwner",
         "type": "address"
       }
     ],
@@ -806,6 +806,20 @@ const GovernanceABIJSON = `
     "type": "function"
   },
   {
+    "constant": false,
+    "inputs": [
+      {
+        "name": "NewOwner",
+        "type": "address"
+      }
+    ],
+    "name": "transferNodeOwnership",
+    "outputs": [],
+    "payable": false,
+    "stateMutability": "nonpayable",
+    "type": "function"
+  },
+  {
     "constant": true,
     "inputs": [],
     "name": "nodesLength",
diff --git a/core/vm/oracle_contracts.go b/core/vm/oracle_contracts.go
index 4168c7b37..836489420 100644
--- a/core/vm/oracle_contracts.go
+++ b/core/vm/oracle_contracts.go
@@ -240,7 +240,6 @@ func (s *GovernanceState) read1DByteArray(loc *big.Int) [][]byte {
 		elementLoc := new(big.Int).Add(dataLoc, big.NewInt(i))
 		data = append(data, s.readBytes(elementLoc))
 	}
-
 	return data
 }
 
@@ -517,13 +516,13 @@ func (s *GovernanceState) DeleteNodeOffsets(n *nodeInfo) error {
 	return nil
 }
 
-func (s *GovernanceState) GetNodeOwnerByID(id coreTypes.NodeID) (common.Address, error) {
+func (s *GovernanceState) GetNodeByID(id coreTypes.NodeID) (*nodeInfo, error) {
 	offset := s.NodesOffsetByNodeKeyAddress(idToAddress(id))
 	if offset.Cmp(big.NewInt(0)) < 0 {
-		return common.Address{}, errors.New("node not found")
+		return nil, errors.New("node not found")
 	}
 	node := s.Node(offset)
-	return node.Owner, nil
+	return node, nil
 }
 
 // uint256 public crsRound;
@@ -1270,9 +1269,11 @@ func (g *GovernanceContract) addDKGComplaint(round *big.Int, comp []byte) ([]byt
 		return g.penalize()
 	}
 	if need {
+		node, err := g.state.GetNodeByID(dkgComplaint.PrivateShare.ProposerID)
+		if err != nil {
+			return g.penalize()
+		}
 		fineValue := g.state.FineValue(big.NewInt(ReportTypeInvalidDKG))
-		offset := g.state.NodesOffsetByNodeKeyAddress(idToAddress(dkgComplaint.PrivateShare.ProposerID))
-		node := g.state.Node(offset)
 		if err := g.fine(node.Owner, fineValue, comp, nil); err != nil {
 			return g.penalize()
 		}
@@ -1703,8 +1704,10 @@ func (g *GovernanceContract) report(reportType *big.Int, arg1, arg2 []byte) ([]b
 		return g.penalize()
 	}
 
-	offset := g.state.NodesOffsetByNodeKeyAddress(idToAddress(reportedNodeID))
-	node := g.state.Node(offset)
+	node, err := g.state.GetNodeByID(reportedNodeID)
+	if err != nil {
+		return g.penalize()
+	}
 
 	g.state.emitForkReported(node.Owner, reportType, arg1, arg2)
 
@@ -1931,6 +1934,12 @@ func (g *GovernanceContract) Run(evm *EVM, input []byte, contract *Contract) (re
 			return nil, errExecutionReverted
 		}
 		return g.transferOwnership(newOwner)
+	case "transferNodeOwnership":
+		var newOwner common.Address
+		if err := method.Inputs.Unpack(&newOwner, arguments); err != nil {
+			return nil, errExecutionReverted
+		}
+		return g.transferNodeOwnership(newOwner)
 	case "unstake":
 		amount := new(big.Int)
 		if err := method.Inputs.Unpack(&amount, arguments); err != nil {
@@ -2219,6 +2228,24 @@ func (g *GovernanceContract) transferOwnership(newOwner common.Address) ([]byte,
 	return nil, nil
 }
 
+func (g *GovernanceContract) transferNodeOwnership(newOwner common.Address) ([]byte, error) {
+	caller := g.contract.Caller()
+
+	offset := g.state.NodesOffsetByAddress(caller)
+	if offset.Cmp(big.NewInt(0)) < 0 {
+		return g.penalize()
+	}
+
+	node := g.state.Node(offset)
+	g.state.PutNodeOffsets(node, big.NewInt(0))
+
+	node.Owner = newOwner
+	g.state.PutNodeOffsets(node, offset)
+	g.state.UpdateNode(offset, node)
+
+	return nil, nil
+}
+
 func PackProposeCRS(round uint64, signedCRS []byte) ([]byte, error) {
 	method := GovernanceABI.Name2Method["proposeCRS"]
 	res, err := method.Inputs.Pack(big.NewInt(int64(round)), signedCRS)
diff --git a/core/vm/oracle_contracts_test.go b/core/vm/oracle_contracts_test.go
index 0b8b7b4f7..436923aa3 100644
--- a/core/vm/oracle_contracts_test.go
+++ b/core/vm/oracle_contracts_test.go
@@ -239,6 +239,39 @@ func (g *OracleContractsTestSuite) TestTransferOwnership() {
 	g.Require().Equal(addr, g.s.Owner())
 }
 
+func (g *OracleContractsTestSuite) TestTransferNodeOwnership() {
+	privKey, addr := g.newPrefundAccount()
+	pk := crypto.FromECDSAPub(&privKey.PublicKey)
+	nodeKeyAddr := crypto.PubkeyToAddress(privKey.PublicKey)
+
+	amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(1e6))
+	input, err := GovernanceABI.ABI.Pack("register", pk, "Test1", "test1@dexon.org", "Taipei", "https://dexon.org")
+	g.Require().NoError(err)
+	_, err = g.call(GovernanceContractAddress, addr, input, amount)
+	g.Require().NoError(err)
+
+	offset := g.s.NodesOffsetByAddress(addr)
+
+	_, newAddr := g.newPrefundAccount()
+	newNodeKeyAddr := crypto.PubkeyToAddress(privKey.PublicKey)
+
+	input, err = GovernanceABI.ABI.Pack("transferNodeOwnership", newAddr)
+	g.Require().NoError(err)
+
+	// Call with non-owner.
+	_, noneOwner := g.newPrefundAccount()
+	_, err = g.call(GovernanceContractAddress, noneOwner, input, big.NewInt(0))
+	g.Require().Error(err)
+
+	// Call with owner.
+	_, err = g.call(GovernanceContractAddress, addr, input, big.NewInt(0))
+	g.Require().NoError(err)
+	g.Require().Equal(uint64(0), g.s.NodesOffsetByAddress(addr).Uint64())
+	g.Require().Equal(uint64(0), g.s.NodesOffsetByNodeKeyAddress(nodeKeyAddr).Uint64())
+	g.Require().Equal(offset.Uint64(), g.s.NodesOffsetByAddress(newAddr).Uint64())
+	g.Require().Equal(offset.Uint64(), g.s.NodesOffsetByNodeKeyAddress(newNodeKeyAddr).Uint64())
+}
+
 func (g *OracleContractsTestSuite) TestStakingMechanism() {
 	privKey, addr := g.newPrefundAccount()
 	pk := crypto.FromECDSAPub(&privKey.PublicKey)