evm: params (#458)

* evm: params

* setup

* bump commit

* fixes

* increase gas usage

* tests

* evm denom param

* more config updates

* update genesis

* update ante handler

* csdb param test

* more tests and fixes

* update statedb.Copy

* lint

* additional test

* fix importer tests

* fix AnteHandler test

* minor update

* revert

* undo gas update

* stringer test

* changelog

* fix csdb index error (#493)

* attempt to fix

* cleanup

* add idx check

* update csdb.Copy

* update default hash

* update querier

* update rpc tests

* fix estimate gas test

Co-authored-by: noot <36753753+noot@users.noreply.github.com>
Co-authored-by: noot <elizabethjbinks@gmail.com>

CHANGELOG.md

@@ -40,6 +40,9 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Improvements
 
 * (app) [\#471](https://github.com/ChainSafe/ethermint/pull/471) Add `x/upgrade` module for managing software updates.
+* (`x/evm`) [\#458](https://github.com/ChainSafe/ethermint/pull/458) Define parameter for token denomination used for the EVM module.
+* (`x/evm`) [\#443](https://github.com/ChainSafe/ethermint/issues/443) Support custom Ethereum `ChainConfig` params.
+* (types) [\#434](https://github.com/ChainSafe/ethermint/issues/434) Update default denomination to Atto Photon (`aphoton`).
 
 ### Bug Fixes
 

Makefile

@@ -211,7 +211,7 @@ test-race:
 
 test-import:
 	@go test ./importer -v --vet=off --run=TestImportBlocks --datadir tmp \
-	--blockchain blockchain --timeout=10m
+	--blockchain blockchain
 	rm -rf importer/tmp
 
 test-rpc:

app/ante/ante.go

@@ -6,7 +6,6 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/auth"
 	authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
 	"github.com/cosmos/cosmos-sdk/x/auth/types"
-	"github.com/cosmos/cosmos-sdk/x/bank"
 
 	"github.com/cosmos/ethermint/crypto"
 	evmtypes "github.com/cosmos/ethermint/x/evm/types"
@@ -29,7 +28,7 @@ const (
 // Ethereum or SDK transaction to an internal ante handler for performing
 // transaction-level processing (e.g. fee payment, signature verification) before
 // being passed onto it's respective handler.
-func NewAnteHandler(ak auth.AccountKeeper, bk bank.Keeper, sk types.SupplyKeeper) sdk.AnteHandler {
+func NewAnteHandler(ak auth.AccountKeeper, evmKeeper EVMKeeper, sk types.SupplyKeeper) sdk.AnteHandler {
 	return func(
 		ctx sdk.Context, tx sdk.Tx, sim bool,
 	) (newCtx sdk.Context, err error) {
@@ -53,11 +52,11 @@ func NewAnteHandler(ak auth.AccountKeeper, bk bank.Keeper, sk types.SupplyKeeper
 		case evmtypes.MsgEthereumTx:
 			anteHandler = sdk.ChainAnteDecorators(
 				NewEthSetupContextDecorator(), // outermost AnteDecorator. EthSetUpContext must be called first
-				NewEthMempoolFeeDecorator(),
+				NewEthMempoolFeeDecorator(evmKeeper),
 				NewEthSigVerificationDecorator(),
-				NewAccountVerificationDecorator(ak, bk),
+				NewAccountVerificationDecorator(ak, evmKeeper),
 				NewNonceVerificationDecorator(ak),
-				NewEthGasConsumeDecorator(ak, sk),
+				NewEthGasConsumeDecorator(ak, sk, evmKeeper),
 				NewIncrementSenderSequenceDecorator(ak), // innermost AnteDecorator.
 			)
 		default:

app/ante/ante_test.go

@@ -254,8 +254,9 @@ func (suite *AnteTestSuite) TestEthInvalidMempoolFees() {
 	// setup app with checkTx = true
 	suite.app = app.Setup(true)
 	suite.ctx = suite.app.BaseApp.NewContext(true, abci.Header{Height: 1, ChainID: "3", Time: time.Now().UTC()})
-	suite.anteHandler = ante.NewAnteHandler(suite.app.AccountKeeper, suite.app.BankKeeper, suite.app.SupplyKeeper)
+	suite.app.EvmKeeper.SetParams(suite.ctx, evmtypes.DefaultParams())
 
+	suite.anteHandler = ante.NewAnteHandler(suite.app.AccountKeeper, suite.app.EvmKeeper, suite.app.SupplyKeeper)
 	suite.ctx = suite.ctx.WithMinGasPrices(sdk.NewDecCoins(sdk.NewDecCoin(types.DenomDefault, sdk.NewInt(500000))))
 	addr1, priv1 := newTestAddrKey()
 	addr2, _ := newTestAddrKey()

app/ante/eth.go

@@ -9,7 +9,6 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/auth"
 	authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
 	"github.com/cosmos/cosmos-sdk/x/auth/types"
-	"github.com/cosmos/cosmos-sdk/x/bank"
 
 	emint "github.com/cosmos/ethermint/types"
 	evmtypes "github.com/cosmos/ethermint/x/evm/types"
@@ -18,6 +17,11 @@ import (
 	ethcore "github.com/ethereum/go-ethereum/core"
 )
 
+// EVMKeeper defines the expected keeper interface used on the Eth AnteHandler
+type EVMKeeper interface {
+	GetParams(ctx sdk.Context) evmtypes.Params
+}
+
 // EthSetupContextDecorator sets the infinite GasMeter in the Context and wraps
 // the next AnteHandler with a defer clause to recover from any downstream
 // OutOfGas panics in the AnteHandler chain to return an error with information
@@ -68,11 +72,15 @@ func (escd EthSetupContextDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simu
 
 // EthMempoolFeeDecorator validates that sufficient fees have been provided that
 // meet a minimum threshold defined by the proposer (for mempool purposes during CheckTx).
-type EthMempoolFeeDecorator struct{}
+type EthMempoolFeeDecorator struct {
+	evmKeeper EVMKeeper
+}
 
 // NewEthMempoolFeeDecorator creates a new EthMempoolFeeDecorator
-func NewEthMempoolFeeDecorator() EthMempoolFeeDecorator {
+func NewEthMempoolFeeDecorator(ek EVMKeeper) EthMempoolFeeDecorator {
-	return EthMempoolFeeDecorator{}
+	return EthMempoolFeeDecorator{
+		evmKeeper: ek,
+	}
 }
 
 // AnteHandle verifies that enough fees have been provided by the
@@ -90,8 +98,10 @@ func (emfd EthMempoolFeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simula
 		return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type: %T", tx)
 	}
 
+	evmDenom := emfd.evmKeeper.GetParams(ctx).EvmDenom
+
 	// fee = GP * GL
-	fee := sdk.NewInt64DecCoin(emint.DenomDefault, msgEthTx.Fee().Int64())
+	fee := sdk.NewInt64DecCoin(evmDenom, msgEthTx.Fee().Int64())
 
 	minGasPrices := ctx.MinGasPrices()
 
@@ -99,7 +109,7 @@ func (emfd EthMempoolFeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simula
 	// NOTE: we only check if aphotons are present in min gas prices. It is up to the
 	// sender if they want to send additional fees in other denominations.
 	var hasEnoughFees bool
-	if fee.Amount.GTE(minGasPrices.AmountOf(emint.DenomDefault)) {
+	if fee.Amount.GTE(minGasPrices.AmountOf(evmDenom)) {
 		hasEnoughFees = true
 	}
 
@@ -150,15 +160,15 @@ func (esvd EthSigVerificationDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, s
 
 // AccountVerificationDecorator validates an account balance checks
 type AccountVerificationDecorator struct {
-	ak auth.AccountKeeper
+	ak        auth.AccountKeeper
-	bk bank.Keeper
+	evmKeeper EVMKeeper
 }
 
 // NewAccountVerificationDecorator creates a new AccountVerificationDecorator
-func NewAccountVerificationDecorator(ak auth.AccountKeeper, bk bank.Keeper) AccountVerificationDecorator {
+func NewAccountVerificationDecorator(ak auth.AccountKeeper, ek EVMKeeper) AccountVerificationDecorator {
 	return AccountVerificationDecorator{
-		ak: ak,
+		ak:        ak,
-		bk: bk,
+		evmKeeper: ek,
 	}
 }
 
@@ -192,12 +202,14 @@ func (avd AccountVerificationDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, s
 		)
 	}
 
+	evmDenom := avd.evmKeeper.GetParams(ctx).EvmDenom
+
 	// validate sender has enough funds to pay for gas cost
-	balance := sdk.Coin{Denom: emint.DenomDefault, Amount: acc.GetCoins().AmountOf(emint.DenomDefault)}
+	balance := acc.GetCoins().AmountOf(evmDenom)
-	if balance.Amount.BigInt().Cmp(msgEthTx.Cost()) < 0 {
+	if balance.BigInt().Cmp(msgEthTx.Cost()) < 0 {
 		return ctx, sdkerrors.Wrapf(
 			sdkerrors.ErrInsufficientFunds,
-			"sender balance < tx gas cost (%s < %s%s)", balance.String(), msgEthTx.Cost().String(), emint.DenomDefault,
+			"sender balance < tx gas cost (%s%s < %s%s)", balance.String(), evmDenom, msgEthTx.Cost().String(), evmDenom,
 		)
 	}
 
@@ -250,15 +262,17 @@ func (nvd NonceVerificationDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, sim
 // EthGasConsumeDecorator validates enough intrinsic gas for the transaction and
 // gas consumption.
 type EthGasConsumeDecorator struct {
-	ak auth.AccountKeeper
+	ak        auth.AccountKeeper
-	sk types.SupplyKeeper
+	sk        types.SupplyKeeper
+	evmKeeper EVMKeeper
 }
 
 // NewEthGasConsumeDecorator creates a new EthGasConsumeDecorator
-func NewEthGasConsumeDecorator(ak auth.AccountKeeper, sk types.SupplyKeeper) EthGasConsumeDecorator {
+func NewEthGasConsumeDecorator(ak auth.AccountKeeper, sk types.SupplyKeeper, ek EVMKeeper) EthGasConsumeDecorator {
 	return EthGasConsumeDecorator{
-		ak: ak,
+		ak:        ak,
-		sk: sk,
+		sk:        sk,
+		evmKeeper: ek,
 	}
 }
 
@@ -307,8 +321,10 @@ func (egcd EthGasConsumeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simula
 		// Cost calculates the fees paid to validators based on gas limit and price
 		cost := new(big.Int).Mul(msgEthTx.Data.Price, new(big.Int).SetUint64(gasLimit))
 
+		evmDenom := egcd.evmKeeper.GetParams(ctx).EvmDenom
+
 		feeAmt := sdk.NewCoins(
-			sdk.NewCoin(emint.DenomDefault, sdk.NewIntFromBigInt(cost)),
+			sdk.NewCoin(evmDenom, sdk.NewIntFromBigInt(cost)),
 		)
 
 		err = auth.DeductFees(egcd.sk, ctx, senderAcc, feeAmt)

app/ante/utils_test.go

@@ -38,7 +38,9 @@ func (suite *AnteTestSuite) SetupTest() {
 	suite.app.Codec().RegisterConcrete(&sdk.TestMsg{}, "test/TestMsg", nil)
 
 	suite.ctx = suite.app.BaseApp.NewContext(checkTx, abci.Header{Height: 1, ChainID: "3", Time: time.Now().UTC()})
-	suite.anteHandler = ante.NewAnteHandler(suite.app.AccountKeeper, suite.app.BankKeeper, suite.app.SupplyKeeper)
+	suite.app.EvmKeeper.SetParams(suite.ctx, evmtypes.DefaultParams())
+
+	suite.anteHandler = ante.NewAnteHandler(suite.app.AccountKeeper, suite.app.EvmKeeper, suite.app.SupplyKeeper)
 }
 
 func TestAnteTestSuite(t *testing.T) {

app/ethermint.go

@@ -148,7 +148,7 @@ func NewEthermintApp(
 
 	cdc := ethermintcodec.MakeCodec(ModuleBasics)
 
-	// use custom Ethermint transaction decoder
+	// NOTE we use custom Ethermint transaction decoder that supports the sdk.Tx interface instead of sdk.StdTx
 	bApp := bam.NewBaseApp(appName, logger, db, evm.TxDecoder(cdc), baseAppOptions...)
 	bApp.SetCommitMultiStoreTracer(traceStore)
 	bApp.SetAppVersion(version.Version)
@@ -182,6 +182,7 @@ func NewEthermintApp(
 	app.subspaces[gov.ModuleName] = app.ParamsKeeper.Subspace(gov.DefaultParamspace).WithKeyTable(gov.ParamKeyTable())
 	app.subspaces[crisis.ModuleName] = app.ParamsKeeper.Subspace(crisis.DefaultParamspace)
 	app.subspaces[evidence.ModuleName] = app.ParamsKeeper.Subspace(evidence.DefaultParamspace)
+	app.subspaces[evm.ModuleName] = app.ParamsKeeper.Subspace(evm.DefaultParamspace)
 
 	// use custom Ethermint account for contracts
 	app.AccountKeeper = auth.NewAccountKeeper(
@@ -212,7 +213,7 @@ func NewEthermintApp(
 	)
 	app.UpgradeKeeper = upgrade.NewKeeper(skipUpgradeHeights, keys[upgrade.StoreKey], app.cdc)
 	app.EvmKeeper = evm.NewKeeper(
-		app.cdc, keys[evm.StoreKey], app.AccountKeeper,
+		app.cdc, keys[evm.StoreKey], app.subspaces[evm.ModuleName], app.AccountKeeper,
 	)
 	app.FaucetKeeper = faucet.NewKeeper(
 		app.cdc, keys[faucet.StoreKey], app.SupplyKeeper,
@@ -311,7 +312,7 @@ func NewEthermintApp(
 	// initialize BaseApp
 	app.SetInitChainer(app.InitChainer)
 	app.SetBeginBlocker(app.BeginBlocker)
-	app.SetAnteHandler(ante.NewAnteHandler(app.AccountKeeper, app.BankKeeper, app.SupplyKeeper))
+	app.SetAnteHandler(ante.NewAnteHandler(app.AccountKeeper, app.EvmKeeper, app.SupplyKeeper))
 	app.SetEndBlocker(app.EndBlocker)
 
 	if loadLatest {

importer/importer_test.go

@@ -26,6 +26,7 @@ import (
 	"github.com/cosmos/ethermint/core"
 	emintcrypto "github.com/cosmos/ethermint/crypto"
 	"github.com/cosmos/ethermint/types"
+	"github.com/cosmos/ethermint/x/evm"
 	evmtypes "github.com/cosmos/ethermint/x/evm/types"
 
 	ethcmn "github.com/ethereum/go-ethereum/common"
@@ -49,9 +50,6 @@ var (
 
 	genInvestor = ethcmn.HexToAddress("0x756F45E3FA69347A9A973A725E3C98bC4db0b5a0")
 
-	accKey   = sdk.NewKVStoreKey(auth.StoreKey)
-	storeKey = sdk.NewKVStoreKey(evmtypes.StoreKey)
-
 	logger = tmlog.NewNopLogger()
 
 	rewardBig8  = big.NewInt(8)
@@ -101,12 +99,13 @@ func trapSignals() {
 }
 
 // nolint: interfacer
-func createAndTestGenesis(t *testing.T, cms sdk.CommitMultiStore, ak auth.AccountKeeper) {
+func createAndTestGenesis(t *testing.T, cms sdk.CommitMultiStore, ak auth.AccountKeeper, evmKeeper evm.Keeper) {
 	genBlock := ethcore.DefaultGenesisBlock()
 	ms := cms.CacheMultiStore()
 	ctx := sdk.NewContext(ms, abci.Header{}, false, logger)
 
-	stateDB := evmtypes.NewCommitStateDB(ctx, storeKey, ak)
+	// Set the default Ethermint parameters to the parameter keeper store
+	evmKeeper.SetParams(ctx, evmtypes.DefaultParams())
 
 	// sort the addresses and insertion of key/value pairs matters
 	genAddrs := make([]string, len(genBlock.Alloc))
@@ -122,23 +121,23 @@ func createAndTestGenesis(t *testing.T, cms sdk.CommitMultiStore, ak auth.Accoun
 		addr := ethcmn.HexToAddress(addrStr)
 		acc := genBlock.Alloc[addr]
 
-		stateDB.AddBalance(addr, acc.Balance)
+		evmKeeper.AddBalance(ctx, addr, acc.Balance)
-		stateDB.SetCode(addr, acc.Code)
+		evmKeeper.SetCode(ctx, addr, acc.Code)
-		stateDB.SetNonce(addr, acc.Nonce)
+		evmKeeper.SetNonce(ctx, addr, acc.Nonce)
 
 		for key, value := range acc.Storage {
-			stateDB.SetState(addr, key, value)
+			evmKeeper.SetState(ctx, addr, key, value)
 		}
 	}
 
 	// get balance of one of the genesis account having 400 ETH
-	b := stateDB.GetBalance(genInvestor)
+	b := evmKeeper.GetBalance(ctx, genInvestor)
 	require.Equal(t, "200000000000000000000", b.String())
 
 	// commit the stateDB with 'false' to delete empty objects
 	//
 	// NOTE: Commit does not yet return the intra merkle root (version)
-	_, err := stateDB.Commit(false)
+	_, err := evmKeeper.Commit(ctx, false)
 	require.NoError(t, err)
 
 	// persist multi-store cache state
@@ -176,20 +175,27 @@ func TestImportBlocks(t *testing.T) {
 
 	cms := store.NewCommitMultiStore(db)
 
-	// The ParamsKeeper handles parameter storage for the application
+	authStoreKey := sdk.NewKVStoreKey(auth.StoreKey)
-	keyParams := sdk.NewKVStoreKey(params.StoreKey)
+	evmStoreKey := sdk.NewKVStoreKey(evmtypes.StoreKey)
-	tkeyParams := sdk.NewTransientStoreKey(params.TStoreKey)
+	paramsStoreKey := sdk.NewKVStoreKey(params.StoreKey)
-	paramsKeeper := params.NewKeeper(cdc, keyParams, tkeyParams)
+	paramsTransientStoreKey := sdk.NewTransientStoreKey(params.TStoreKey)
-	// Set specific supspaces
-	authSubspace := paramsKeeper.Subspace(auth.DefaultParamspace)
-	ak := auth.NewAccountKeeper(cdc, accKey, authSubspace, types.ProtoAccount)
 
 	// mount stores
-	keys := []*sdk.KVStoreKey{accKey, storeKey}
+	keys := []*sdk.KVStoreKey{authStoreKey, evmStoreKey, paramsStoreKey}
 	for _, key := range keys {
 		cms.MountStoreWithDB(key, sdk.StoreTypeIAVL, nil)
 	}
 
+	cms.MountStoreWithDB(paramsTransientStoreKey, sdk.StoreTypeTransient, nil)
+
+	paramsKeeper := params.NewKeeper(cdc, paramsStoreKey, paramsTransientStoreKey)
+
+	// Set specific subspaces
+	authSubspace := paramsKeeper.Subspace(auth.DefaultParamspace)
+	evmSubspace := paramsKeeper.Subspace(evmtypes.DefaultParamspace).WithKeyTable(evmtypes.ParamKeyTable())
+	ak := auth.NewAccountKeeper(cdc, authStoreKey, authSubspace, types.ProtoAccount)
+	evmKeeper := evm.NewKeeper(cdc, evmStoreKey, evmSubspace, ak)
+
 	cms.SetPruning(sdkstore.PruneNothing)
 
 	// load latest version (root)
@@ -197,7 +203,7 @@ func TestImportBlocks(t *testing.T) {
 	require.NoError(t, err)
 
 	// set and test genesis block
-	createAndTestGenesis(t, cms, ak)
+	createAndTestGenesis(t, cms, ak, evmKeeper)
 
 	// open blockchain export file
 	blockchainInput, err := os.Open(flagBlockchain)
@@ -242,27 +248,25 @@ func TestImportBlocks(t *testing.T) {
 		ctx := sdk.NewContext(ms, abci.Header{}, false, logger)
 		ctx = ctx.WithBlockHeight(int64(block.NumberU64()))
 
-		stateDB := createStateDB(ctx, ak)
-
 		if chainConfig.DAOForkSupport && chainConfig.DAOForkBlock != nil && chainConfig.DAOForkBlock.Cmp(block.Number()) == 0 {
-			applyDAOHardFork(stateDB)
+			applyDAOHardFork(evmKeeper)
 		}
 
 		for i, tx := range block.Transactions() {
-			stateDB.Prepare(tx.Hash(), block.Hash(), i)
+			evmKeeper.Prepare(ctx, tx.Hash(), block.Hash(), i)
 
 			receipt, gas, err := applyTransaction(
-				chainConfig, chainContext, nil, gp, stateDB, header, tx, usedGas, vmConfig,
+				chainConfig, chainContext, nil, gp, evmKeeper, header, tx, usedGas, vmConfig,
 			)
 			require.NoError(t, err, "failed to apply tx at block %d; tx: %X; gas %d; receipt:%v", block.NumberU64(), tx.Hash(), gas, receipt)
 			require.NotNil(t, receipt)
 		}
 
 		// apply mining rewards
-		accumulateRewards(chainConfig, stateDB, header, block.Uncles())
+		accumulateRewards(chainConfig, evmKeeper, header, block.Uncles())
 
 		// commit stateDB
-		_, err := stateDB.Commit(chainConfig.IsEIP158(block.Number()))
+		_, err := evmKeeper.CommitStateDB.Commit(chainConfig.IsEIP158(block.Number()))
 		require.NoError(t, err, "failed to commit StateDB")
 
 		// simulate BaseApp EndBlocker commitment
@@ -276,16 +280,11 @@ func TestImportBlocks(t *testing.T) {
 	}
 }
 
-// nolint: interfacer
-func createStateDB(ctx sdk.Context, ak auth.AccountKeeper) *evmtypes.CommitStateDB {
-	return evmtypes.NewCommitStateDB(ctx, storeKey, ak)
-}
-
 // accumulateRewards credits the coinbase of the given block with the mining
 // reward. The total reward consists of the static block reward and rewards for
 // included uncles. The coinbase of each uncle block is also rewarded.
 func accumulateRewards(
-	config *ethparams.ChainConfig, stateDB *evmtypes.CommitStateDB,
+	config *ethparams.ChainConfig, evmKeeper evm.Keeper,
 	header *ethtypes.Header, uncles []*ethtypes.Header,
 ) {
 
@@ -304,12 +303,12 @@ func accumulateRewards(
 		r.Sub(r, header.Number)
 		r.Mul(r, blockReward)
 		r.Div(r, rewardBig8)
-		stateDB.AddBalance(uncle.Coinbase, r)
+		evmKeeper.CommitStateDB.AddBalance(uncle.Coinbase, r)
 		r.Div(blockReward, rewardBig32)
 		reward.Add(reward, r)
 	}
 
-	stateDB.AddBalance(header.Coinbase, reward)
+	evmKeeper.CommitStateDB.AddBalance(header.Coinbase, reward)
 }
 
 // ApplyDAOHardFork modifies the state database according to the DAO hard-fork
@@ -318,16 +317,16 @@ func accumulateRewards(
 // Code is pulled from go-ethereum 1.9 because the StateDB interface does not include the
 // SetBalance function implementation
 // Ref: https://github.com/ethereum/go-ethereum/blob/52f2461774bcb8cdd310f86b4bc501df5b783852/consensus/misc/dao.go#L74
-func applyDAOHardFork(statedb *evmtypes.CommitStateDB) {
+func applyDAOHardFork(evmKeeper evm.Keeper) {
 	// Retrieve the contract to refund balances into
-	if !statedb.Exist(ethparams.DAORefundContract) {
+	if !evmKeeper.CommitStateDB.Exist(ethparams.DAORefundContract) {
-		statedb.CreateAccount(ethparams.DAORefundContract)
+		evmKeeper.CommitStateDB.CreateAccount(ethparams.DAORefundContract)
 	}
 
 	// Move every DAO account and extra-balance account funds into the refund contract
 	for _, addr := range ethparams.DAODrainList() {
-		statedb.AddBalance(ethparams.DAORefundContract, statedb.GetBalance(addr))
+		evmKeeper.CommitStateDB.AddBalance(ethparams.DAORefundContract, evmKeeper.CommitStateDB.GetBalance(addr))
-		statedb.SetBalance(addr, new(big.Int))
+		evmKeeper.CommitStateDB.SetBalance(addr, new(big.Int))
 	}
 }
 
@@ -339,7 +338,7 @@ func applyDAOHardFork(statedb *evmtypes.CommitStateDB) {
 // Ref: https://github.com/ethereum/go-ethereum/blob/52f2461774bcb8cdd310f86b4bc501df5b783852/core/state_processor.go#L88
 func applyTransaction(
 	config *ethparams.ChainConfig, bc ethcore.ChainContext, author *ethcmn.Address,
-	gp *ethcore.GasPool, statedb *evmtypes.CommitStateDB, header *ethtypes.Header,
+	gp *ethcore.GasPool, evmKeeper evm.Keeper, header *ethtypes.Header,
 	tx *ethtypes.Transaction, usedGas *uint64, cfg ethvm.Config,
 ) (*ethtypes.Receipt, uint64, error) {
 	msg, err := tx.AsMessage(ethtypes.MakeSigner(config, header.Number))
@@ -352,7 +351,7 @@ func applyTransaction(
 
 	// Create a new environment which holds all relevant information
 	// about the transaction and calling mechanisms.
-	vmenv := ethvm.NewEVM(context, statedb, config, cfg)
+	vmenv := ethvm.NewEVM(context, evmKeeper.CommitStateDB, config, cfg)
 
 	// Apply the transaction to the current state (included in the env)
 	execResult, err := ethcore.ApplyMessage(vmenv, msg, gp)
@@ -364,9 +363,9 @@ func applyTransaction(
 	// Update the state with pending changes
 	var intRoot ethcmn.Hash
 	if config.IsByzantium(header.Number) {
-		err = statedb.Finalise(true)
+		err = evmKeeper.CommitStateDB.Finalise(true)
 	} else {
-		intRoot, err = statedb.IntermediateRoot(config.IsEIP158(header.Number))
+		intRoot, err = evmKeeper.CommitStateDB.IntermediateRoot(config.IsEIP158(header.Number))
 	}
 
 	if err != nil {
@@ -388,11 +387,11 @@ func applyTransaction(
 	}
 
 	// Set the receipt logs and create a bloom for filtering
-	receipt.Logs, err = statedb.GetLogs(tx.Hash())
+	receipt.Logs, err = evmKeeper.CommitStateDB.GetLogs(tx.Hash())
 	receipt.Bloom = ethtypes.CreateBloom(ethtypes.Receipts{receipt})
-	receipt.BlockHash = statedb.BlockHash()
+	receipt.BlockHash = evmKeeper.CommitStateDB.BlockHash()
 	receipt.BlockNumber = header.Number
-	receipt.TransactionIndex = uint(statedb.TxIndex())
+	receipt.TransactionIndex = uint(evmKeeper.CommitStateDB.TxIndex())
 
 	return receipt, execResult.UsedGas, err
 }

tests/rpc_test.go

@@ -751,12 +751,14 @@ func TestEth_EstimateGas(t *testing.T) {
 	param[0]["to"] = "0x1122334455667788990011223344556677889900"
 	param[0]["value"] = "0x1"
 	rpcRes := call(t, "eth_estimateGas", param)
+	require.NotNil(t, rpcRes)
+	require.NotEmpty(t, rpcRes.Result)
 
-	var gas hexutil.Bytes
+	var gas string
 	err := json.Unmarshal(rpcRes.Result, &gas)
-	require.NoError(t, err)
+	require.NoError(t, err, string(rpcRes.Result))
 
-	require.Equal(t, "0xffdf", gas.String())
+	require.Equal(t, "0x1051d", gas)
 }
 
 func TestEth_EstimateGas_ContractDeployment(t *testing.T) {
@@ -768,12 +770,14 @@ func TestEth_EstimateGas_ContractDeployment(t *testing.T) {
 	param[0]["data"] = bytecode
 
 	rpcRes := call(t, "eth_estimateGas", param)
+	require.NotNil(t, rpcRes)
+	require.NotEmpty(t, rpcRes.Result)
 
 	var gas hexutil.Uint64
 	err := json.Unmarshal(rpcRes.Result, &gas)
-	require.NoError(t, err)
+	require.NoError(t, err, string(rpcRes.Result))
 
-	require.Equal(t, hexutil.Uint64(0x1cab2), gas)
+	require.Equal(t, "0x1cab2", gas.String())
 }
 
 func TestEth_ExportAccount(t *testing.T) {
@@ -831,10 +835,10 @@ func TestEth_ExportAccount_WithStorage(t *testing.T) {
 	require.NoError(t, err)
 
 	// deployed bytecode
-	bytecode := ethcmn.FromHex("0x6080604052348015600f57600080fd5b506004361060285760003560e01c8063eb8ac92114602d575b600080fd5b606060048036036040811015604157600080fd5b8101908080359060200190929190803590602001909291905050506062565b005b8160008190555080827ff3ca124a697ba07e8c5e80bebcfcc48991fc16a63170e8a9206e30508960d00360405160405180910390a3505056fea265627a7a723158201d94d2187aaf3a6790527b615fcc40970febf0385fa6d72a2344848ebd0df3e964736f6c63430005110032")
+	bytecode := "0x6080604052348015600f57600080fd5b506004361060285760003560e01c8063eb8ac92114602d575b600080fd5b606060048036036040811015604157600080fd5b8101908080359060200190929190803590602001909291905050506062565b005b8160008190555080827ff3ca124a697ba07e8c5e80bebcfcc48991fc16a63170e8a9206e30508960d00360405160405180910390a3505056fea265627a7a723158201d94d2187aaf3a6790527b615fcc40970febf0385fa6d72a2344848ebd0df3e964736f6c63430005110032"
 	require.Equal(t, addr, strings.ToLower(account.Address.Hex()))
 	require.Equal(t, big.NewInt(0), account.Balance)
-	require.Equal(t, hexutil.Bytes(bytecode), account.Code)
+	require.Equal(t, bytecode, account.Code.String())
 	require.NotEqual(t, types.Storage(nil), account.Storage)
 }
 

x/evm/alias.go

@@ -7,9 +7,10 @@ import (
 
 // nolint
 const (
-	ModuleName = types.ModuleName
+	ModuleName        = types.ModuleName
-	StoreKey   = types.StoreKey
+	StoreKey          = types.StoreKey
-	RouterKey  = types.RouterKey
+	RouterKey         = types.RouterKey
+	DefaultParamspace = types.DefaultParamspace
 )
 
 // nolint

x/evm/genesis.go

@@ -28,6 +28,9 @@ func InitGenesis(ctx sdk.Context, k Keeper, data GenesisState) []abci.ValidatorU
 		}
 	}
 
+	k.SetChainConfig(ctx, data.ChainConfig)
+	k.SetParams(ctx, data.Params)
+
 	// set state objects and code to store
 	_, err = k.Commit(ctx, false)
 	if err != nil {
@@ -74,8 +77,12 @@ func ExportGenesis(ctx sdk.Context, k Keeper, ak types.AccountKeeper) GenesisSta
 		ethGenAccounts = append(ethGenAccounts, genAccount)
 	}
 
+	config, _ := k.GetChainConfig(ctx)
+
 	return GenesisState{
-		Accounts: ethGenAccounts,
+		Accounts:    ethGenAccounts,
-		TxsLogs:  k.GetAllTxLogs(ctx),
+		TxsLogs:     k.GetAllTxLogs(ctx),
+		ChainConfig: config,
+		Params:      k.GetParams(ctx),
 	}
 }

x/evm/handler.go

@@ -65,8 +65,12 @@ func handleMsgEthereumTx(ctx sdk.Context, k Keeper, msg types.MsgEthereumTx) (*s
 	k.CommitStateDB.Prepare(ethHash, common.Hash{}, k.TxCount)
 	k.TxCount++
 
-	// TODO: move to keeper
+	config, found := k.GetChainConfig(ctx)
-	executionResult, err := st.TransitionDb(ctx)
+	if !found {
+		return nil, types.ErrChainConfigNotFound
+	}
+
+	executionResult, err := st.TransitionDb(ctx, config)
 	if err != nil {
 		return nil, err
 	}
@@ -142,7 +146,12 @@ func handleMsgEthermint(ctx sdk.Context, k Keeper, msg types.MsgEthermint) (*sdk
 	k.CommitStateDB.Prepare(ethHash, common.Hash{}, k.TxCount)
 	k.TxCount++
 
-	executionResult, err := st.TransitionDb(ctx)
+	config, found := k.GetChainConfig(ctx)
+	if !found {
+		return nil, types.ErrChainConfigNotFound
+	}
+
+	executionResult, err := st.TransitionDb(ctx, config)
 	if err != nil {
 		return nil, err
 	}

x/evm/keeper/keeper.go

@@ -10,6 +10,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/codec"
 	"github.com/cosmos/cosmos-sdk/store/prefix"
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/x/params"
 
 	"github.com/cosmos/ethermint/x/evm/types"
 
@@ -28,7 +29,8 @@ type Keeper struct {
 	// - storing transaction Logs
 	// - storing block height -> bloom filter map. Needed for the Web3 API.
 	// - storing block hash -> block height map. Needed for the Web3 API.
-	storeKey      sdk.StoreKey
+	storeKey sdk.StoreKey
+	// Ethermint concrete implementation on the EVM StateDB interface
 	CommitStateDB *types.CommitStateDB
 	// Transaction counter in a block. Used on StateSB's Prepare function.
 	// It is reset to 0 every block on BeginBlock so there's no point in storing the counter
@@ -39,12 +41,18 @@ type Keeper struct {
 
 // NewKeeper generates new evm module keeper
 func NewKeeper(
-	cdc *codec.Codec, storeKey sdk.StoreKey, ak types.AccountKeeper,
+	cdc *codec.Codec, storeKey sdk.StoreKey, paramSpace params.Subspace, ak types.AccountKeeper,
 ) Keeper {
+	// set KeyTable if it has not already been set
+	if !paramSpace.HasKeyTable() {
+		paramSpace = paramSpace.WithKeyTable(types.ParamKeyTable())
+	}
+
+	// NOTE: we pass in the parameter space to the CommitStateDB in order to use custom denominations for the EVM operations
 	return Keeper{
 		cdc:           cdc,
 		storeKey:      storeKey,
-		CommitStateDB: types.NewCommitStateDB(sdk.Context{}, storeKey, ak),
+		CommitStateDB: types.NewCommitStateDB(sdk.Context{}, storeKey, paramSpace, ak),
 		TxCount:       0,
 		Bloom:         big.NewInt(0),
 	}
@@ -134,3 +142,25 @@ func (k Keeper) GetAccountStorage(ctx sdk.Context, address common.Address) (type
 
 	return storage, nil
 }
+
+// GetChainConfig gets block height from block consensus hash
+func (k Keeper) GetChainConfig(ctx sdk.Context) (types.ChainConfig, bool) {
+	store := prefix.NewStore(ctx.KVStore(k.storeKey), types.KeyPrefixChainConfig)
+	// get from an empty key that's already prefixed by KeyPrefixChainConfig
+	bz := store.Get([]byte{})
+	if len(bz) == 0 {
+		return types.ChainConfig{}, false
+	}
+
+	var config types.ChainConfig
+	k.cdc.MustUnmarshalBinaryBare(bz, &config)
+	return config, true
+}
+
+// SetChainConfig sets the mapping from block consensus hash to block height
+func (k Keeper) SetChainConfig(ctx sdk.Context, config types.ChainConfig) {
+	store := prefix.NewStore(ctx.KVStore(k.storeKey), types.KeyPrefixChainConfig)
+	bz := k.cdc.MustMarshalBinaryBare(config)
+	// get to an empty key that's already prefixed by KeyPrefixChainConfig
+	store.Set([]byte{}, bz)
+}

x/evm/keeper/keeper_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/cosmos/ethermint/app"
 	ethermint "github.com/cosmos/ethermint/types"
 	"github.com/cosmos/ethermint/x/evm/keeper"
+	"github.com/cosmos/ethermint/x/evm/types"
 
 	ethcmn "github.com/ethereum/go-ethereum/common"
 	ethtypes "github.com/ethereum/go-ethereum/core/types"
@@ -148,3 +149,15 @@ func (suite *KeeperTestSuite) TestDBStorage() {
 	// simulate BaseApp EndBlocker commitment
 	suite.app.Commit()
 }
+
+func (suite *KeeperTestSuite) TestChainConfig() {
+	config, found := suite.app.EvmKeeper.GetChainConfig(suite.ctx)
+	suite.Require().True(found)
+	suite.Require().Equal(types.DefaultChainConfig(), config)
+
+	config.EIP150Block = sdk.NewInt(100)
+	suite.app.EvmKeeper.SetChainConfig(suite.ctx, config)
+	newConfig, found := suite.app.EvmKeeper.GetChainConfig(suite.ctx)
+	suite.Require().True(found)
+	suite.Require().Equal(config, newConfig)
+}

x/evm/keeper/params.go

@@ -0,0 +1,17 @@
+package keeper
+
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	"github.com/cosmos/ethermint/x/evm/types"
+)
+
+// GetParams returns the total set of evm parameters.
+func (k Keeper) GetParams(ctx sdk.Context) (params types.Params) {
+	return k.CommitStateDB.WithContext(ctx).GetParams()
+}
+
+// SetParams sets the evm parameters to the param space.
+func (k Keeper) SetParams(ctx sdk.Context, params types.Params) {
+	k.CommitStateDB.WithContext(ctx).SetParams(params)
+}

x/evm/keeper/params_test.go

@@ -0,0 +1,14 @@
+package keeper_test
+
+import (
+	"github.com/cosmos/ethermint/x/evm/types"
+)
+
+func (suite *KeeperTestSuite) TestParams() {
+	params := suite.app.EvmKeeper.GetParams(suite.ctx)
+	suite.Require().Equal(types.DefaultParams(), params)
+	params.EvmDenom = "ara"
+	suite.app.EvmKeeper.SetParams(suite.ctx, params)
+	newParams := suite.app.EvmKeeper.GetParams(suite.ctx)
+	suite.Require().Equal(newParams, params)
+}

x/evm/keeper/querier.go

@@ -21,7 +21,7 @@ import (
 
 // NewQuerier is the module level router for state queries
 func NewQuerier(keeper Keeper) sdk.Querier {
-	return func(ctx sdk.Context, path []string, req abci.RequestQuery) ([]byte, error) {
+	return func(ctx sdk.Context, path []string, _ abci.RequestQuery) ([]byte, error) {
 		switch path[0] {
 		case types.QueryProtocolVersion:
 			return queryProtocolVersion(keeper)
@@ -203,7 +203,7 @@ func queryExportAccount(ctx sdk.Context, path []string, keeper Keeper) ([]byte,
 	addr := ethcmn.HexToAddress(path[1])
 
 	var storage types.Storage
-	err := keeper.CommitStateDB.ForEachStorage(addr, func(key, value ethcmn.Hash) bool {
+	err := keeper.ForEachStorage(ctx, addr, func(key, value ethcmn.Hash) bool {
 		storage = append(storage, types.NewState(key, value))
 		return false
 	})

x/evm/module_test.go

@@ -18,8 +18,11 @@ var testJSON = `{
           "address": "0x2cc7fdf9fde6746731d7f11979609d455c2c197a",
           "balance": 0,
           "code": "0x60806040"
-        }
+				}
-      ]
+			],
+			"params": {
+				"evm_denom": "aphoton"
+			}
  	}`
 
 func (suite *EvmTestSuite) TestInitGenesis() {

x/evm/types/chain_config.go

@@ -2,25 +2,171 @@ package types
 
 import (
 	"math/big"
+	"strings"
+
+	"gopkg.in/yaml.v2"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/params"
 )
 
-// GenerateChainConfig returns an Ethereum chainconfig for EVM state transitions
+// ChainConfig defines the Ethereum ChainConfig parameters using sdk.Int values instead of big.Int.
-func GenerateChainConfig(chainID *big.Int) *params.ChainConfig {
+//
-	// TODO: Update chainconfig to take in parameters for fork blocks
+// NOTE 1: Since empty/uninitialized Ints (i.e with a nil big.Int value) are parsed to zero, we need to manually
+// specify that negative Int values will be considered as nil. See getBlockValue for reference.
+//
+// NOTE 2: This type is not a configurable Param since the SDK does not allow for validation against
+// a previous stored parameter values or the current block height (retrieved from context). If you
+// want to update the config values, use an software upgrade procedure.
+type ChainConfig struct {
+	HomesteadBlock sdk.Int `json:"homestead_block" yaml:"homestead_block"` // Homestead switch block (< 0 no fork, 0 = already homestead)
+
+	DAOForkBlock   sdk.Int `json:"dao_fork_block" yaml:"dao_fork_block"`     // TheDAO hard-fork switch block (< 0 no fork)
+	DAOForkSupport bool    `json:"dao_fork_support" yaml:"dao_fork_support"` // Whether the nodes supports or opposes the DAO hard-fork
+
+	// EIP150 implements the Gas price changes (https://github.com/ethereum/EIPs/issues/150)
+	EIP150Block sdk.Int `json:"eip150_block" yaml:"eip150_block"` // EIP150 HF block (< 0 no fork)
+	EIP150Hash  string  `json:"eip150_hash" yaml:"eip150_hash"`   // EIP150 HF hash (needed for header only clients as only gas pricing changed)
+
+	EIP155Block sdk.Int `json:"eip155_block" yaml:"eip155_block"` // EIP155 HF block
+	EIP158Block sdk.Int `json:"eip158_block" yaml:"eip158_block"` // EIP158 HF block
+
+	ByzantiumBlock      sdk.Int `json:"byzantium_block" yaml:"byzantium_block"`           // Byzantium switch block (< 0 no fork, 0 = already on byzantium)
+	ConstantinopleBlock sdk.Int `json:"constantinople_block" yaml:"constantinople_block"` // Constantinople switch block (< 0 no fork, 0 = already activated)
+	PetersburgBlock     sdk.Int `json:"petersburg_block" yaml:"petersburg_block"`         // Petersburg switch block (< 0 same as Constantinople)
+	IstanbulBlock       sdk.Int `json:"istanbul_block" yaml:"istanbul_block"`             // Istanbul switch block (< 0 no fork, 0 = already on istanbul)
+	MuirGlacierBlock    sdk.Int `json:"muir_glacier_block" yaml:"muir_glacier_block"`     // Eip-2384 (bomb delay) switch block (< 0 no fork, 0 = already activated)
+
+	YoloV1Block sdk.Int `json:"yoloV1_block" yaml:"yoloV1_block"` // YOLO v1: https://github.com/ethereum/EIPs/pull/2657 (Ephemeral testnet)
+	EWASMBlock  sdk.Int `json:"ewasm_block" yaml:"ewasm_block"`   // EWASM switch block (< 0 no fork, 0 = already activated)
+}
+
+// EthereumConfig returns an Ethereum ChainConfig for EVM state transitions.
+// All the negative or nil values are converted to nil
+func (cc ChainConfig) EthereumConfig(chainID *big.Int) *params.ChainConfig {
 	return &params.ChainConfig{
 		ChainID:             chainID,
-		HomesteadBlock:      big.NewInt(0),
+		HomesteadBlock:      getBlockValue(cc.HomesteadBlock),
-		DAOForkBlock:        big.NewInt(0),
+		DAOForkBlock:        getBlockValue(cc.DAOForkBlock),
-		DAOForkSupport:      true,
+		DAOForkSupport:      cc.DAOForkSupport,
-		EIP150Block:         big.NewInt(0),
+		EIP150Block:         getBlockValue(cc.EIP150Block),
-		EIP150Hash:          common.HexToHash("0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0"),
+		EIP150Hash:          common.HexToHash(cc.EIP150Hash),
-		EIP155Block:         big.NewInt(0),
+		EIP155Block:         getBlockValue(cc.EIP155Block),
-		EIP158Block:         big.NewInt(0),
+		EIP158Block:         getBlockValue(cc.EIP158Block),
-		ByzantiumBlock:      big.NewInt(0),
+		ByzantiumBlock:      getBlockValue(cc.ByzantiumBlock),
-		ConstantinopleBlock: big.NewInt(0),
+		ConstantinopleBlock: getBlockValue(cc.ConstantinopleBlock),
-		PetersburgBlock:     big.NewInt(0),
+		PetersburgBlock:     getBlockValue(cc.PetersburgBlock),
+		IstanbulBlock:       getBlockValue(cc.IstanbulBlock),
+		MuirGlacierBlock:    getBlockValue(cc.MuirGlacierBlock),
+		YoloV1Block:         getBlockValue(cc.YoloV1Block),
+		EWASMBlock:          getBlockValue(cc.EWASMBlock),
 	}
 }
+
+// String implements the fmt.Stringer interface
+func (cc ChainConfig) String() string {
+	out, _ := yaml.Marshal(cc)
+	return string(out)
+}
+
+// DefaultChainConfig returns default evm parameters. Th
+func DefaultChainConfig() ChainConfig {
+	return ChainConfig{
+		HomesteadBlock:      sdk.ZeroInt(),
+		DAOForkBlock:        sdk.ZeroInt(),
+		DAOForkSupport:      true,
+		EIP150Block:         sdk.ZeroInt(),
+		EIP150Hash:          common.Hash{}.String(),
+		EIP155Block:         sdk.ZeroInt(),
+		EIP158Block:         sdk.ZeroInt(),
+		ByzantiumBlock:      sdk.ZeroInt(),
+		ConstantinopleBlock: sdk.ZeroInt(),
+		PetersburgBlock:     sdk.ZeroInt(),
+		IstanbulBlock:       sdk.NewInt(-1),
+		MuirGlacierBlock:    sdk.NewInt(-1),
+		YoloV1Block:         sdk.NewInt(-1),
+		EWASMBlock:          sdk.NewInt(-1),
+	}
+}
+
+func getBlockValue(block sdk.Int) *big.Int {
+	if block.IsNegative() {
+		return nil
+	}
+
+	return block.BigInt()
+}
+
+// Validate performs a basic validation of the ChainConfig params. The function will return an error
+// if any of the block values is uninitialized (i.e nil) or if the EIP150Hash is an invalid hash.
+func (cc ChainConfig) Validate() error {
+	if err := validateBlock(cc.HomesteadBlock); err != nil {
+		return sdkerrors.Wrap(err, "homesteadBlock")
+	}
+	if err := validateBlock(cc.DAOForkBlock); err != nil {
+		return sdkerrors.Wrap(err, "daoForkBlock")
+	}
+	if err := validateBlock(cc.EIP150Block); err != nil {
+		return sdkerrors.Wrap(err, "eip150Block")
+	}
+	if err := validateHash(cc.EIP150Hash); err != nil {
+		return err
+	}
+	if err := validateBlock(cc.EIP155Block); err != nil {
+		return sdkerrors.Wrap(err, "eip155Block")
+	}
+	if err := validateBlock(cc.EIP158Block); err != nil {
+		return sdkerrors.Wrap(err, "eip158Block")
+	}
+	if err := validateBlock(cc.ByzantiumBlock); err != nil {
+		return sdkerrors.Wrap(err, "byzantiumBlock")
+	}
+	if err := validateBlock(cc.ConstantinopleBlock); err != nil {
+		return sdkerrors.Wrap(err, "constantinopleBlock")
+	}
+	if err := validateBlock(cc.PetersburgBlock); err != nil {
+		return sdkerrors.Wrap(err, "petersburgBlock")
+	}
+	if err := validateBlock(cc.IstanbulBlock); err != nil {
+		return sdkerrors.Wrap(err, "istanbulBlock")
+	}
+	if err := validateBlock(cc.MuirGlacierBlock); err != nil {
+		return sdkerrors.Wrap(err, "muirGlacierBlock")
+	}
+	if err := validateBlock(cc.YoloV1Block); err != nil {
+		return sdkerrors.Wrap(err, "yoloV1Block")
+	}
+	if err := validateBlock(cc.EWASMBlock); err != nil {
+		return sdkerrors.Wrap(err, "eWASMBlock")
+	}
+
+	return nil
+}
+
+func validateHash(hex string) error {
+	if hex != "" && strings.TrimSpace(hex) == "" {
+		return sdkerrors.Wrapf(ErrInvalidChainConfig, "hash cannot be blank")
+	}
+
+	bz := common.FromHex(hex)
+	lenHex := len(bz)
+	if lenHex > 0 && lenHex != common.HashLength {
+		return sdkerrors.Wrapf(ErrInvalidChainConfig, "invalid hash length, expected %d, got %d", common.HashLength, lenHex)
+	}
+
+	return nil
+}
+
+func validateBlock(block sdk.Int) error {
+	if block == (sdk.Int{}) || block.BigInt() == nil {
+		return sdkerrors.Wrapf(
+			ErrInvalidChainConfig,
+			"cannot use uninitialized or nil values for Int, set a negative Int value if you want to define a nil Ethereum block",
+		)
+	}
+
+	return nil
+}

x/evm/types/chain_config_test.go

@@ -0,0 +1,245 @@
+package types
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+var defaultEIP150Hash = common.Hash{}.String()
+
+func TestChainConfigValidate(t *testing.T) {
+	testCases := []struct {
+		name     string
+		config   ChainConfig
+		expError bool
+	}{
+		{"default", DefaultChainConfig(), false},
+		{
+			"valid",
+			ChainConfig{
+				HomesteadBlock:      sdk.OneInt(),
+				DAOForkBlock:        sdk.OneInt(),
+				EIP150Block:         sdk.OneInt(),
+				EIP150Hash:          defaultEIP150Hash,
+				EIP155Block:         sdk.OneInt(),
+				EIP158Block:         sdk.OneInt(),
+				ByzantiumBlock:      sdk.OneInt(),
+				ConstantinopleBlock: sdk.OneInt(),
+				PetersburgBlock:     sdk.OneInt(),
+				IstanbulBlock:       sdk.OneInt(),
+				MuirGlacierBlock:    sdk.OneInt(),
+				YoloV1Block:         sdk.OneInt(),
+				EWASMBlock:          sdk.OneInt(),
+			},
+			false,
+		},
+		{
+			"empty",
+			ChainConfig{},
+			true,
+		},
+		{
+			"invalid HomesteadBlock",
+			ChainConfig{
+				HomesteadBlock: sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid DAOForkBlock",
+			ChainConfig{
+				HomesteadBlock: sdk.OneInt(),
+				DAOForkBlock:   sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid EIP150Block",
+			ChainConfig{
+				HomesteadBlock: sdk.OneInt(),
+				DAOForkBlock:   sdk.OneInt(),
+				EIP150Block:    sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid EIP150Hash",
+			ChainConfig{
+				HomesteadBlock: sdk.OneInt(),
+				DAOForkBlock:   sdk.OneInt(),
+				EIP150Block:    sdk.OneInt(),
+				EIP150Hash:     "  ",
+			},
+			true,
+		},
+		{
+			"invalid EIP155Block",
+			ChainConfig{
+				HomesteadBlock: sdk.OneInt(),
+				DAOForkBlock:   sdk.OneInt(),
+				EIP150Block:    sdk.OneInt(),
+				EIP150Hash:     defaultEIP150Hash,
+				EIP155Block:    sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid EIP158Block",
+			ChainConfig{
+				HomesteadBlock: sdk.OneInt(),
+				DAOForkBlock:   sdk.OneInt(),
+				EIP150Block:    sdk.OneInt(),
+				EIP150Hash:     defaultEIP150Hash,
+				EIP155Block:    sdk.OneInt(),
+				EIP158Block:    sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid ByzantiumBlock",
+			ChainConfig{
+				HomesteadBlock: sdk.OneInt(),
+				DAOForkBlock:   sdk.OneInt(),
+				EIP150Block:    sdk.OneInt(),
+				EIP150Hash:     defaultEIP150Hash,
+				EIP155Block:    sdk.OneInt(),
+				EIP158Block:    sdk.OneInt(),
+				ByzantiumBlock: sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid ConstantinopleBlock",
+			ChainConfig{
+				HomesteadBlock:      sdk.OneInt(),
+				DAOForkBlock:        sdk.OneInt(),
+				EIP150Block:         sdk.OneInt(),
+				EIP150Hash:          defaultEIP150Hash,
+				EIP155Block:         sdk.OneInt(),
+				EIP158Block:         sdk.OneInt(),
+				ByzantiumBlock:      sdk.OneInt(),
+				ConstantinopleBlock: sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid PetersburgBlock",
+			ChainConfig{
+				HomesteadBlock:      sdk.OneInt(),
+				DAOForkBlock:        sdk.OneInt(),
+				EIP150Block:         sdk.OneInt(),
+				EIP150Hash:          defaultEIP150Hash,
+				EIP155Block:         sdk.OneInt(),
+				EIP158Block:         sdk.OneInt(),
+				ByzantiumBlock:      sdk.OneInt(),
+				ConstantinopleBlock: sdk.OneInt(),
+				PetersburgBlock:     sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid IstanbulBlock",
+			ChainConfig{
+				HomesteadBlock:      sdk.OneInt(),
+				DAOForkBlock:        sdk.OneInt(),
+				EIP150Block:         sdk.OneInt(),
+				EIP150Hash:          defaultEIP150Hash,
+				EIP155Block:         sdk.OneInt(),
+				EIP158Block:         sdk.OneInt(),
+				ByzantiumBlock:      sdk.OneInt(),
+				ConstantinopleBlock: sdk.OneInt(),
+				PetersburgBlock:     sdk.OneInt(),
+				IstanbulBlock:       sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid MuirGlacierBlock",
+			ChainConfig{
+				HomesteadBlock:      sdk.OneInt(),
+				DAOForkBlock:        sdk.OneInt(),
+				EIP150Block:         sdk.OneInt(),
+				EIP150Hash:          defaultEIP150Hash,
+				EIP155Block:         sdk.OneInt(),
+				EIP158Block:         sdk.OneInt(),
+				ByzantiumBlock:      sdk.OneInt(),
+				ConstantinopleBlock: sdk.OneInt(),
+				PetersburgBlock:     sdk.OneInt(),
+				IstanbulBlock:       sdk.OneInt(),
+				MuirGlacierBlock:    sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid YoloV1Block",
+			ChainConfig{
+				HomesteadBlock:      sdk.OneInt(),
+				DAOForkBlock:        sdk.OneInt(),
+				EIP150Block:         sdk.OneInt(),
+				EIP150Hash:          defaultEIP150Hash,
+				EIP155Block:         sdk.OneInt(),
+				EIP158Block:         sdk.OneInt(),
+				ByzantiumBlock:      sdk.OneInt(),
+				ConstantinopleBlock: sdk.OneInt(),
+				PetersburgBlock:     sdk.OneInt(),
+				IstanbulBlock:       sdk.OneInt(),
+				MuirGlacierBlock:    sdk.OneInt(),
+				YoloV1Block:         sdk.Int{},
+			},
+			true,
+		},
+		{
+			"invalid EWASMBlock",
+			ChainConfig{
+				HomesteadBlock:      sdk.OneInt(),
+				DAOForkBlock:        sdk.OneInt(),
+				EIP150Block:         sdk.OneInt(),
+				EIP150Hash:          defaultEIP150Hash,
+				EIP155Block:         sdk.OneInt(),
+				EIP158Block:         sdk.OneInt(),
+				ByzantiumBlock:      sdk.OneInt(),
+				ConstantinopleBlock: sdk.OneInt(),
+				PetersburgBlock:     sdk.OneInt(),
+				IstanbulBlock:       sdk.OneInt(),
+				MuirGlacierBlock:    sdk.OneInt(),
+				YoloV1Block:         sdk.OneInt(),
+				EWASMBlock:          sdk.Int{},
+			},
+			true,
+		},
+	}
+
+	for _, tc := range testCases {
+		err := tc.config.Validate()
+
+		if tc.expError {
+			require.Error(t, err, tc.name)
+		} else {
+			require.NoError(t, err, tc.name)
+		}
+	}
+}
+
+func TestChainConfig_String(t *testing.T) {
+	configStr := `homestead_block: "0"
+dao_fork_block: "0"
+dao_fork_support: true
+eip150_block: "0"
+eip150_hash: "0x0000000000000000000000000000000000000000000000000000000000000000"
+eip155_block: "0"
+eip158_block: "0"
+byzantium_block: "0"
+constantinople_block: "0"
+petersburg_block: "0"
+istanbul_block: "-1"
+muir_glacier_block: "-1"
+yoloV1_block: "-1"
+ewasm_block: "-1"
+`
+	require.Equal(t, configStr, DefaultChainConfig().String())
+}

x/evm/types/codec.go

@@ -13,6 +13,7 @@ func RegisterCodec(cdc *codec.Codec) {
 	cdc.RegisterConcrete(MsgEthereumTx{}, "ethermint/MsgEthereumTx", nil)
 	cdc.RegisterConcrete(MsgEthermint{}, "ethermint/MsgEthermint", nil)
 	cdc.RegisterConcrete(TxData{}, "ethermint/TxData", nil)
+	cdc.RegisterConcrete(ChainConfig{}, "ethermint/ChainConfig", nil)
 }
 
 func init() {

x/evm/types/errors.go

@@ -9,4 +9,10 @@ import (
 var (
 	// ErrInvalidState returns an error resulting from an invalid Storage State.
 	ErrInvalidState = sdkerrors.Register(ModuleName, 2, "invalid storage state")
+
+	// ErrChainConfigNotFound returns an error if the chain config cannot be found on the store.
+	ErrChainConfigNotFound = sdkerrors.Register(ModuleName, 3, "chain configuration not found")
+
+	// ErrInvalidChainConfig returns an error resulting from an invalid ChainConfig.
+	ErrInvalidChainConfig = sdkerrors.Register(ModuleName, 4, "invalid chain configuration")
 )

x/evm/types/genesis.go

@@ -13,8 +13,10 @@ import (
 type (
 	// GenesisState defines the evm module genesis state
 	GenesisState struct {
-		Accounts []GenesisAccount  `json:"accounts"`
+		Accounts    []GenesisAccount  `json:"accounts"`
-		TxsLogs  []TransactionLogs `json:"txs_logs"`
+		TxsLogs     []TransactionLogs `json:"txs_logs"`
+		ChainConfig ChainConfig       `json:"chain_config"`
+		Params      Params            `json:"params"`
 	}
 
 	// GenesisAccount defines an account to be initialized in the genesis state.
@@ -46,11 +48,14 @@ func (ga GenesisAccount) Validate() error {
 	return ga.Storage.Validate()
 }
 
-// DefaultGenesisState sets default evm genesis state with empty accounts.
+// DefaultGenesisState sets default evm genesis state with empty accounts and default params and
+// chain config values.
 func DefaultGenesisState() GenesisState {
 	return GenesisState{
-		Accounts: []GenesisAccount{},
+		Accounts:    []GenesisAccount{},
-		TxsLogs:  []TransactionLogs{},
+		TxsLogs:     []TransactionLogs{},
+		ChainConfig: DefaultChainConfig(),
+		Params:      DefaultParams(),
 	}
 }
 
@@ -80,5 +85,9 @@ func (gs GenesisState) Validate() error {
 		seenTxs[tx.Hash.String()] = true
 	}
 
-	return nil
+	if err := gs.ChainConfig.Validate(); err != nil {
+		return err
+	}
+
+	return gs.Params.Validate()
 }

x/evm/types/genesis_test.go

@@ -122,9 +122,16 @@ func TestValidateGenesis(t *testing.T) {
 						},
 					},
 				},
+				ChainConfig: DefaultChainConfig(),
+				Params:      DefaultParams(),
 			},
 			expPass: true,
 		},
+		{
+			name:     "empty genesis",
+			genState: GenesisState{},
+			expPass:  false,
+		},
 		{
 			name: "invalid genesis",
 			genState: GenesisState{
@@ -227,6 +234,22 @@ func TestValidateGenesis(t *testing.T) {
 			},
 			expPass: false,
 		},
+		{
+			name: "invalid params",
+			genState: GenesisState{
+				ChainConfig: DefaultChainConfig(),
+				Params:      Params{},
+			},
+			expPass: false,
+		},
+		{
+			name: "invalid chain config",
+			genState: GenesisState{
+				ChainConfig: ChainConfig{},
+				Params:      DefaultParams(),
+			},
+			expPass: false,
+		},
 	}
 
 	for _, tc := range testCases {

x/evm/types/journal_test.go

@@ -15,6 +15,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/store"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/x/auth"
+	"github.com/cosmos/cosmos-sdk/x/gov/types"
 	"github.com/cosmos/cosmos-sdk/x/params"
 
 	ethcmn "github.com/ethereum/go-ethereum/common"
@@ -119,11 +120,12 @@ func (suite *JournalTestSuite) setup() {
 	paramsKeeper := params.NewKeeper(cdc, keyParams, tkeyParams)
 
 	authSubspace := paramsKeeper.Subspace(auth.DefaultParamspace)
+	evmSubspace := paramsKeeper.Subspace(types.DefaultParamspace)
 
 	ak := auth.NewAccountKeeper(cdc, authKey, authSubspace, ethermint.ProtoAccount)
 
 	suite.ctx = sdk.NewContext(cms, abci.Header{ChainID: "8"}, false, tmlog.NewNopLogger())
-	suite.stateDB = NewCommitStateDB(suite.ctx, storeKey, ak).WithContext(suite.ctx)
+	suite.stateDB = NewCommitStateDB(suite.ctx, storeKey, evmSubspace, ak).WithContext(suite.ctx)
 }
 
 func TestJournalTestSuite(t *testing.T) {

x/evm/types/key.go

@@ -21,11 +21,12 @@ const (
 
 // KVStore key prefixes
 var (
-	KeyPrefixBlockHash = []byte{0x01}
+	KeyPrefixBlockHash   = []byte{0x01}
-	KeyPrefixBloom     = []byte{0x02}
+	KeyPrefixBloom       = []byte{0x02}
-	KeyPrefixLogs      = []byte{0x03}
+	KeyPrefixLogs        = []byte{0x03}
-	KeyPrefixCode      = []byte{0x04}
+	KeyPrefixCode        = []byte{0x04}
-	KeyPrefixStorage   = []byte{0x05}
+	KeyPrefixStorage     = []byte{0x05}
+	KeyPrefixChainConfig = []byte{0x06}
 )
 
 // BloomKey defines the store key for a block Bloom

x/evm/types/params.go

@@ -0,0 +1,73 @@
+package types
+
+import (
+	"fmt"
+
+	"gopkg.in/yaml.v2"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/x/params"
+
+	ethermint "github.com/cosmos/ethermint/types"
+)
+
+const (
+	// DefaultParamspace for params keeper
+	DefaultParamspace = ModuleName
+)
+
+// Parameter keys
+var (
+	ParamStoreKeyEVMDenom = []byte("EVMDenom")
+)
+
+// ParamKeyTable returns the parameter key table.
+func ParamKeyTable() params.KeyTable {
+	return params.NewKeyTable().RegisterParamSet(&Params{})
+}
+
+// Params defines the EVM module parameters
+type Params struct {
+	EvmDenom string `json:"evm_denom" yaml:"evm_denom"`
+}
+
+// NewParams creates a new Params instance
+func NewParams(evmDenom string) Params {
+	return Params{
+		EvmDenom: evmDenom,
+	}
+}
+
+// DefaultParams returns default evm parameters
+func DefaultParams() Params {
+	return Params{
+		EvmDenom: ethermint.DenomDefault,
+	}
+}
+
+// String implements the fmt.Stringer interface
+func (p Params) String() string {
+	out, _ := yaml.Marshal(p)
+	return string(out)
+}
+
+// ParamSetPairs returns the parameter set pairs.
+func (p *Params) ParamSetPairs() params.ParamSetPairs {
+	return params.ParamSetPairs{
+		params.NewParamSetPair(ParamStoreKeyEVMDenom, &p.EvmDenom, validateEVMDenom),
+	}
+}
+
+// Validate performs basic validation on evm parameters.
+func (p Params) Validate() error {
+	return sdk.ValidateDenom(p.EvmDenom)
+}
+
+func validateEVMDenom(i interface{}) error {
+	denom, ok := i.(string)
+	if !ok {
+		return fmt.Errorf("invalid parameter type: %T", i)
+	}
+
+	return sdk.ValidateDenom(denom)
+}

x/evm/types/params_test.go

@@ -0,0 +1,52 @@
+package types
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestParamsValidate(t *testing.T) {
+	testCases := []struct {
+		name     string
+		params   Params
+		expError bool
+	}{
+		{"default", DefaultParams(), false},
+		{
+			"valid",
+			NewParams("ara"),
+			false,
+		},
+		{
+			"empty",
+			Params{},
+			true,
+		},
+		{
+			"invalid evm denom",
+			Params{
+				EvmDenom: "@!#!@$!@5^32",
+			},
+			true,
+		},
+	}
+
+	for _, tc := range testCases {
+		err := tc.params.Validate()
+
+		if tc.expError {
+			require.Error(t, err, tc.name)
+		} else {
+			require.NoError(t, err, tc.name)
+		}
+	}
+}
+
+func TestParamsValidatePriv(t *testing.T) {
+	require.Error(t, validateEVMDenom(false))
+}
+
+func TestParams_String(t *testing.T) {
+	require.Equal(t, "evm_denom: aphoton\n", DefaultParams().String())
+}

x/evm/types/state_object.go

@@ -176,8 +176,8 @@ func (so *stateObject) AddBalance(amount *big.Int) {
 		return
 	}
 
-	// newBalance := so.balance.Add(amt)
+	evmDenom := so.stateDB.GetParams().EvmDenom
-	newBalance := so.account.GetCoins().AmountOf(types.DenomDefault).Add(amt)
+	newBalance := so.account.GetCoins().AmountOf(evmDenom).Add(amt)
 	so.SetBalance(newBalance.BigInt())
 }
 
@@ -188,7 +188,9 @@ func (so *stateObject) SubBalance(amount *big.Int) {
 	if amt.IsZero() {
 		return
 	}
-	newBalance := so.account.GetCoins().AmountOf(types.DenomDefault).Sub(amt)
+
+	evmDenom := so.stateDB.GetParams().EvmDenom
+	newBalance := so.account.GetCoins().AmountOf(evmDenom).Sub(amt)
 	so.SetBalance(newBalance.BigInt())
 }
 
@@ -196,9 +198,10 @@ func (so *stateObject) SubBalance(amount *big.Int) {
 func (so *stateObject) SetBalance(amount *big.Int) {
 	amt := sdk.NewIntFromBigInt(amount)
 
+	evmDenom := so.stateDB.GetParams().EvmDenom
 	so.stateDB.journal.append(balanceChange{
 		account: &so.address,
-		prev:    so.account.GetCoins().AmountOf(types.DenomDefault),
+		prev:    so.account.GetCoins().AmountOf(evmDenom),
 	})
 
 	so.setBalance(amt)

x/evm/types/state_transition.go

@@ -10,8 +10,6 @@ import (
 	ethtypes "github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
 
-	emint "github.com/cosmos/ethermint/types"
-
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 )
@@ -49,7 +47,7 @@ type ExecutionResult struct {
 	GasInfo GasInfo
 }
 
-func (st StateTransition) newEVM(ctx sdk.Context, csdb *CommitStateDB, gasLimit uint64, gasPrice *big.Int) *vm.EVM {
+func (st StateTransition) newEVM(ctx sdk.Context, csdb *CommitStateDB, gasLimit uint64, gasPrice *big.Int, config ChainConfig) *vm.EVM {
 	// Create context for evm
 	context := vm.Context{
 		CanTransfer: core.CanTransfer,
@@ -63,13 +61,13 @@ func (st StateTransition) newEVM(ctx sdk.Context, csdb *CommitStateDB, gasLimit
 		GasPrice:    gasPrice,
 	}
 
-	return vm.NewEVM(context, csdb, GenerateChainConfig(st.ChainID), vm.Config{})
+	return vm.NewEVM(context, csdb, config.EthereumConfig(st.ChainID), vm.Config{})
 }
 
 // TransitionDb will transition the state by applying the current transaction and
 // returning the evm execution result.
 // NOTE: State transition checks are run during AnteHandler execution.
-func (st StateTransition) TransitionDb(ctx sdk.Context) (*ExecutionResult, error) {
+func (st StateTransition) TransitionDb(ctx sdk.Context, config ChainConfig) (*ExecutionResult, error) {
 	contractCreation := st.Recipient == nil
 
 	cost, err := core.IntrinsicGas(st.Payload, contractCreation, true, false)
@@ -103,12 +101,13 @@ func (st StateTransition) TransitionDb(ctx sdk.Context) (*ExecutionResult, error
 	// Clear cache of accounts to handle changes outside of the EVM
 	csdb.UpdateAccounts()
 
-	gasPrice := ctx.MinGasPrices().AmountOf(emint.DenomDefault)
+	evmDenom := csdb.GetParams().EvmDenom
+	gasPrice := ctx.MinGasPrices().AmountOf(evmDenom)
 	if gasPrice.IsNil() {
 		return nil, errors.New("gas price cannot be nil")
 	}
 
-	evm := st.newEVM(ctx, csdb, gasLimit, gasPrice.Int)
+	evm := st.newEVM(ctx, csdb, gasLimit, gasPrice.Int, config)
 
 	var (
 		ret             []byte

x/evm/types/state_transition_test.go

@@ -132,7 +132,7 @@ func (suite *StateDBTestSuite) TestTransitionDb() {
 	for _, tc := range testCase {
 		tc.malleate()
 
-		_, err = tc.state.TransitionDb(suite.ctx)
+		_, err = tc.state.TransitionDb(suite.ctx, types.DefaultChainConfig())
 
 		if tc.expPass {
 			suite.Require().NoError(err, tc.name)

x/evm/types/statedb.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/cosmos/cosmos-sdk/store/prefix"
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/x/params"
 
 	emint "github.com/cosmos/ethermint/types"
 
@@ -42,6 +43,7 @@ type CommitStateDB struct {
 	ctx sdk.Context
 
 	storeKey      sdk.StoreKey
+	paramSpace    params.Subspace
 	accountKeeper AccountKeeper
 
 	// array that hold 'live' objects, which will get modified while processing a
@@ -85,11 +87,12 @@ type CommitStateDB struct {
 // CONTRACT: Stores used for state must be cache-wrapped as the ordering of the
 // key/value space matters in determining the merkle root.
 func NewCommitStateDB(
-	ctx sdk.Context, storeKey sdk.StoreKey, ak AccountKeeper,
+	ctx sdk.Context, storeKey sdk.StoreKey, paramSpace params.Subspace, ak AccountKeeper,
 ) *CommitStateDB {
 	return &CommitStateDB{
 		ctx:                  ctx,
 		storeKey:             storeKey,
+		paramSpace:           paramSpace,
 		accountKeeper:        ak,
 		stateObjects:         []stateEntry{},
 		addressToObjectIndex: make(map[ethcmn.Address]int),
@@ -110,6 +113,11 @@ func (csdb *CommitStateDB) WithContext(ctx sdk.Context) *CommitStateDB {
 // Setters
 // ----------------------------------------------------------------------------
 
+// SetParams sets the evm parameters to the param space.
+func (csdb *CommitStateDB) SetParams(params Params) {
+	csdb.paramSpace.SetParamSet(csdb.ctx, &params)
+}
+
 // SetBalance sets the balance of an account.
 func (csdb *CommitStateDB) SetBalance(addr ethcmn.Address, amount *big.Int) {
 	so := csdb.GetOrNewStateObject(addr)
@@ -239,6 +247,12 @@ func (csdb *CommitStateDB) SubRefund(gas uint64) {
 // Getters
 // ----------------------------------------------------------------------------
 
+// GetParams returns the total set of evm parameters.
+func (csdb *CommitStateDB) GetParams() (params Params) {
+	csdb.paramSpace.GetParamSet(csdb.ctx, &params)
+	return params
+}
+
 // GetBalance retrieves the balance from the given address or 0 if object not
 // found.
 func (csdb *CommitStateDB) GetBalance(addr ethcmn.Address) *big.Int {
@@ -489,8 +503,9 @@ func (csdb *CommitStateDB) IntermediateRoot(deleteEmptyObjects bool) (ethcmn.Has
 
 // updateStateObject writes the given state object to the store.
 func (csdb *CommitStateDB) updateStateObject(so *stateObject) error {
+	evmDenom := csdb.GetParams().EvmDenom
 	// NOTE: we don't use sdk.NewCoin here to avoid panic on test importer's genesis
-	newBalance := sdk.Coin{Denom: emint.DenomDefault, Amount: sdk.NewIntFromBigInt(so.Balance())}
+	newBalance := sdk.Coin{Denom: evmDenom, Amount: sdk.NewIntFromBigInt(so.Balance())}
 	if !newBalance.IsValid() {
 		return fmt.Errorf("invalid balance %s", newBalance)
 	}
@@ -631,9 +646,10 @@ func (csdb *CommitStateDB) UpdateAccounts() {
 			continue
 		}
 
+		evmDenom := csdb.GetParams().EvmDenom
 		balance := sdk.Coin{
-			Denom:  emint.DenomDefault,
+			Denom:  evmDenom,
-			Amount: emintAcc.GetCoins().AmountOf(emint.DenomDefault),
+			Amount: emintAcc.GetCoins().AmountOf(evmDenom),
 		}
 
 		if stateEntry.stateObject.Balance() != balance.Amount.BigInt() && balance.IsValid() ||
@@ -692,6 +708,7 @@ func (csdb *CommitStateDB) Copy() *CommitStateDB {
 	state := &CommitStateDB{
 		ctx:                  csdb.ctx,
 		storeKey:             csdb.storeKey,
+		paramSpace:           csdb.paramSpace,
 		accountKeeper:        csdb.accountKeeper,
 		stateObjects:         []stateEntry{},
 		addressToObjectIndex: make(map[ethcmn.Address]int),
@@ -815,8 +832,7 @@ func (csdb *CommitStateDB) setError(err error) {
 // getStateObject attempts to retrieve a state object given by the address.
 // Returns nil and sets an error if not found.
 func (csdb *CommitStateDB) getStateObject(addr ethcmn.Address) (stateObject *stateObject) {
-	idx, found := csdb.addressToObjectIndex[addr]
+	if idx, found := csdb.addressToObjectIndex[addr]; found {
-	if found {
 		// prefer 'live' (cached) objects
 		if so := csdb.stateObjects[idx].stateObject; so != nil {
 			if so.deleted {
@@ -842,8 +858,7 @@ func (csdb *CommitStateDB) getStateObject(addr ethcmn.Address) (stateObject *sta
 }
 
 func (csdb *CommitStateDB) setStateObject(so *stateObject) {
-	idx, found := csdb.addressToObjectIndex[so.Address()]
+	if idx, found := csdb.addressToObjectIndex[so.Address()]; found {
-	if found {
 		// update the existing object
 		csdb.stateObjects[idx].stateObject = so
 		return

x/evm/types/statedb_test.go

@@ -57,6 +57,16 @@ func (suite *StateDBTestSuite) SetupTest() {
 	suite.app.AccountKeeper.SetAccount(suite.ctx, acc)
 	suite.stateObject = suite.stateDB.GetOrNewStateObject(suite.address)
 }
+
+func (suite *StateDBTestSuite) TestParams() {
+	params := suite.stateDB.GetParams()
+	suite.Require().Equal(types.DefaultParams(), params)
+	params.EvmDenom = "ara"
+	suite.stateDB.SetParams(params)
+	newParams := suite.stateDB.GetParams()
+	suite.Require().Equal(newParams, params)
+}
+
 func (suite *StateDBTestSuite) TestBloomFilter() {
 	// Prepare db for logs
 	tHash := ethcmn.BytesToHash([]byte{0x1})