evm: add ApplyNativeMessage (#557)

* add ApplyNativeMessage

Closes #533

* fix lint

* Update x/evm/types/tracer.go

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

* Update x/evm/types/tracer.go

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

* no-op tracer

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>
Co-authored-by: Federico Kunze <federico.kunze94@gmail.com>

app/ante/eth.go

@@ -362,7 +362,7 @@ func (ctd CanTransferDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate
 		}
 
 		// NOTE: pass in an empty coinbase address and nil tracer as we don't need them for the check below
-		evm := ctd.evmKeeper.NewEVM(coreMsg, ethCfg, params, common.Address{}, nil)
+		evm := ctd.evmKeeper.NewEVM(coreMsg, ethCfg, params, common.Address{}, evmtypes.NewNoOpTracer())
 
 		// check that caller has enough balance to cover asset transfer for **topmost** call
 		// NOTE: here the gas consumed is from the context with the infinite gas meter

x/evm/keeper/state_transition.go

@@ -311,6 +311,38 @@ func (k *Keeper) ApplyMessage(evm *vm.EVM, msg core.Message, cfg *params.ChainCo
 	}, nil
 }
 
+// ApplyNativeMessage executes an ethereum message on the EVM. It is meant to be called from an internal
+// native Cosmos SDK module.
+func (k *Keeper) ApplyNativeMessage(msg core.Message) (*types.MsgEthereumTxResponse, error) {
+	// TODO: clean up and remove duplicate code.
+
+	ctx := k.Ctx()
+	params := k.GetParams(ctx)
+	// return error if contract creation or call are disabled through governance
+	if !params.EnableCreate && msg.To() == nil {
+		return nil, stacktrace.Propagate(types.ErrCreateDisabled, "failed to create new contract")
+	} else if !params.EnableCall && msg.To() != nil {
+		return nil, stacktrace.Propagate(types.ErrCallDisabled, "failed to call contract")
+	}
+
+	ethCfg := params.ChainConfig.EthereumConfig(k.eip155ChainID)
+
+	// get the coinbase address from the block proposer
+	coinbase, err := k.GetCoinbaseAddress(ctx)
+	if err != nil {
+		return nil, stacktrace.Propagate(err, "failed to obtain coinbase address")
+	}
+
+	evm := k.NewEVM(msg, ethCfg, params, coinbase, nil)
+
+	ret, err := k.ApplyMessage(evm, msg, ethCfg, true)
+	if err != nil {
+		return nil, err
+	}
+	k.CommitCachedContexts()
+	return ret, nil
+}
+
 // GetEthIntrinsicGas returns the intrinsic gas cost for the transaction
 func (k *Keeper) GetEthIntrinsicGas(msg core.Message, cfg *params.ChainConfig, isContractCreation bool) (uint64, error) {
 	height := big.NewInt(k.Ctx().BlockHeight())

x/evm/types/tracer.go

@@ -4,7 +4,9 @@ import (
 	"fmt"
 	"math/big"
 	"os"
+	"time"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/params"
@@ -36,7 +38,7 @@ func NewTracer(tracer string, msg core.Message, cfg *params.ChainConfig, height
 	case TracerStruct:
 		return vm.NewStructLogger(logCfg)
 	default:
-		return nil
+		return NewNoOpTracer()
 	}
 }
 
@@ -112,3 +114,28 @@ func FormatLogs(logs []vm.StructLog) []StructLogRes {
 	}
 	return formatted
 }
+
+var _ vm.Tracer = &NoOpTracer{}
+
+// NoOpTracer is an empty implementation of vm.Tracer interface
+type NoOpTracer struct{}
+
+// NewNoOpTracer creates a no-op vm.Tracer
+func NewNoOpTracer() *NoOpTracer {
+	return &NoOpTracer{}
+}
+
+// CaptureStart implements vm.Tracer interface
+func (dt NoOpTracer) CaptureStart(env *vm.EVM, from, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
+}
+
+// CaptureState implements vm.Tracer interface
+func (dt NoOpTracer) CaptureState(env *vm.EVM, pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
+}
+
+// CaptureFault implements vm.Tracer interface
+func (dt NoOpTracer) CaptureFault(env *vm.EVM, pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, depth int, err error) {
+}
+
+// CaptureEnd implements vm.Tracer interface
+func (dt NoOpTracer) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) {}