Add permissioned create

core/vm/can_create.go

@@ -0,0 +1,31 @@
+package vm
+
+import (
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/holiman/uint256"
+)
+
+const canCreateGasLimit = uint64(1000000)
+
+// `bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)`
+var proxyImplementationSlot = common.HexToHash("0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc")
+
+// Predeploy address (may or may not have an implementation behind it)
+var letPredeploy = common.HexToAddress("0x42000000000000000000000000000000000001e7")
+
+// 4-byte signature of `canCreate(address contractCaller)` + 12-byte padding
+var canCreatePrefix = common.FromHex("0x7804a5dc000000000000000000000000")
+
+func CanCreate(evm *EVM, caller ContractRef) error {
+	implementation := evm.StateDB.GetState(letPredeploy, proxyImplementationSlot)
+	if implementation == (common.Hash{}) {
+		return nil
+	}
+	var contractCaller common.Address
+	if contract, ok := caller.(*Contract); ok {
+		contractCaller = contract.Caller()
+	}
+	data := append(canCreatePrefix, contractCaller[:]...)
+	_, _, err := evm.Call(caller, letPredeploy, data, canCreateGasLimit, new(uint256.Int))
+	return err
+}

core/vm/can_create_test.go

@@ -0,0 +1 @@
+package vm

core/vm/evm.go

@@ -459,6 +459,9 @@ func (evm *EVM) create(caller ContractRef, codeAndHash *codeAndHash, gas uint64,
 	if !evm.Context.CanTransfer(evm.StateDB, caller.Address(), value) {
 		return nil, common.Address{}, gas, ErrInsufficientBalance
 	}
+	if err := CanCreate(evm, caller); err != nil {
+		return nil, common.Address{}, gas, err
+	}
 	nonce := evm.StateDB.GetNonce(caller.Address())
 	if nonce+1 < nonce {
 		return nil, common.Address{}, gas, ErrNonceUintOverflow