laconicd-deprecated/app/ante/eth.go

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package ante
import (
"errors"
"math/big"
sdk "github.com/cosmos/cosmos-sdk/types"
sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
ethermint "github.com/tharsis/ethermint/types"
evmkeeper "github.com/tharsis/ethermint/x/evm/keeper"
"github.com/tharsis/ethermint/x/evm/statedb"
evmtypes "github.com/tharsis/ethermint/x/evm/types"
"github.com/ethereum/go-ethereum/common"
ethtypes "github.com/ethereum/go-ethereum/core/types"
)
// EthSigVerificationDecorator validates an ethereum signatures
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type EthSigVerificationDecorator struct {
evmKeeper EVMKeeper
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}
// NewEthSigVerificationDecorator creates a new EthSigVerificationDecorator
func NewEthSigVerificationDecorator(ek EVMKeeper) EthSigVerificationDecorator {
return EthSigVerificationDecorator{
evmKeeper: ek,
}
}
// AnteHandle validates checks that the registered chain id is the same as the one on the message, and
// that the signer address matches the one defined on the message.
// It's not skipped for RecheckTx, because it set `From` address which is critical from other ante handler to work.
// Failure in RecheckTx will prevent tx to be included into block, especially when CheckTx succeed, in which case user
// won't see the error message.
func (esvd EthSigVerificationDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
if tx == nil || len(tx.GetMsgs()) != 1 {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "only 1 ethereum msg supported per tx")
}
chainID := esvd.evmKeeper.ChainID()
params := esvd.evmKeeper.GetParams(ctx)
ethCfg := params.ChainConfig.EthereumConfig(chainID)
blockNum := big.NewInt(ctx.BlockHeight())
signer := ethtypes.MakeSigner(ethCfg, blockNum)
msg := tx.GetMsgs()[0]
msgEthTx, ok := msg.(*evmtypes.MsgEthereumTx)
if !ok {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type %T, expected %T", tx, (*evmtypes.MsgEthereumTx)(nil))
}
sender, err := signer.Sender(msgEthTx.AsTransaction())
if err != nil {
return ctx, sdkerrors.Wrapf(
sdkerrors.ErrorInvalidSigner,
"couldn't retrieve sender address ('%s') from the ethereum transaction: %s",
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msgEthTx.From,
err.Error(),
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)
}
// set up the sender to the transaction field if not already
msgEthTx.From = sender.Hex()
return next(ctx, msgEthTx, simulate)
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}
// EthAccountVerificationDecorator validates an account balance checks
type EthAccountVerificationDecorator struct {
ak evmtypes.AccountKeeper
bankKeeper evmtypes.BankKeeper
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evmKeeper EVMKeeper
}
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// NewEthAccountVerificationDecorator creates a new EthAccountVerificationDecorator
func NewEthAccountVerificationDecorator(ak evmtypes.AccountKeeper, bankKeeper evmtypes.BankKeeper, ek EVMKeeper) EthAccountVerificationDecorator {
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return EthAccountVerificationDecorator{
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ak: ak,
bankKeeper: bankKeeper,
evmKeeper: ek,
}
}
// AnteHandle validates checks that the sender balance is greater than the total transaction cost.
// The account will be set to store if it doesn't exis, i.e cannot be found on store.
// This AnteHandler decorator will fail if:
// - any of the msgs is not a MsgEthereumTx
// - from address is empty
// - account balance is lower than the transaction cost
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func (avd EthAccountVerificationDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
if !ctx.IsCheckTx() {
return next(ctx, tx, simulate)
}
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for i, msg := range tx.GetMsgs() {
msgEthTx, ok := msg.(*evmtypes.MsgEthereumTx)
if !ok {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type %T, expected %T", tx, (*evmtypes.MsgEthereumTx)(nil))
}
txData, err := evmtypes.UnpackTxData(msgEthTx.Data)
if err != nil {
return ctx, sdkerrors.Wrapf(err, "failed to unpack tx data any for tx %d", i)
}
// sender address should be in the tx cache from the previous AnteHandle call
from := msgEthTx.GetFrom()
if from.Empty() {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidAddress, "from address cannot be empty")
}
// check whether the sender address is EOA
fromAddr := common.BytesToAddress(from)
acct, err := avd.evmKeeper.GetAccount(ctx, fromAddr)
if err != nil {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrInvalidType,
"the sender is not EthAccount: address %s", fromAddr)
}
if acct == nil {
acc := avd.ak.NewAccountWithAddress(ctx, from)
avd.ak.SetAccount(ctx, acc)
acct = statedb.NewEmptyAccount()
} else if acct.IsContract() {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrInvalidType,
"the sender is not EOA: address %s, codeHash <%s>", fromAddr, acct.CodeHash)
}
if err := evmkeeper.CheckSenderBalance(sdk.NewIntFromBigInt(acct.Balance), txData); err != nil {
return ctx, sdkerrors.Wrap(err, "failed to check sender balance")
}
}
return next(ctx, tx, simulate)
}
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// EthNonceVerificationDecorator checks that the account nonce from the transaction matches
// the sender account sequence.
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type EthNonceVerificationDecorator struct {
ak evmtypes.AccountKeeper
}
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// NewEthNonceVerificationDecorator creates a new EthNonceVerificationDecorator
func NewEthNonceVerificationDecorator(ak evmtypes.AccountKeeper) EthNonceVerificationDecorator {
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return EthNonceVerificationDecorator{
ak: ak,
}
}
// AnteHandle validates that the transaction nonces are valid and equivalent to the sender accounts
// current nonce.
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func (nvd EthNonceVerificationDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
// no need to check the nonce on ReCheckTx
if ctx.IsReCheckTx() {
return next(ctx, tx, simulate)
}
for _, msg := range tx.GetMsgs() {
msgEthTx, ok := msg.(*evmtypes.MsgEthereumTx)
if !ok {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type %T, expected %T", tx, (*evmtypes.MsgEthereumTx)(nil))
}
// sender address should be in the tx cache from the previous AnteHandle call
seq, err := nvd.ak.GetSequence(ctx, msgEthTx.GetFrom())
if err != nil {
return ctx, sdkerrors.Wrapf(err, "sequence not found for address %s", msgEthTx.From)
}
txData, err := evmtypes.UnpackTxData(msgEthTx.Data)
if err != nil {
return ctx, sdkerrors.Wrap(err, "failed to unpack tx data")
}
// if multiple transactions are submitted in succession with increasing nonces,
// all will be rejected except the first, since the first needs to be included in a block
// before the sequence increments
if txData.GetNonce() != seq {
return ctx, sdkerrors.Wrapf(
sdkerrors.ErrInvalidSequence,
"invalid nonce; got %d, expected %d", txData.GetNonce(), seq,
)
}
}
return next(ctx, tx, simulate)
}
// EthGasConsumeDecorator validates enough intrinsic gas for the transaction and
// gas consumption.
type EthGasConsumeDecorator struct {
evmKeeper EVMKeeper
}
// NewEthGasConsumeDecorator creates a new EthGasConsumeDecorator
func NewEthGasConsumeDecorator(
evmKeeper EVMKeeper,
) EthGasConsumeDecorator {
return EthGasConsumeDecorator{
evmKeeper: evmKeeper,
}
}
// AnteHandle validates that the Ethereum tx message has enough to cover intrinsic gas
// (during CheckTx only) and that the sender has enough balance to pay for the gas cost.
//
// Intrinsic gas for a transaction is the amount of gas that the transaction uses before the
// transaction is executed. The gas is a constant value plus any cost inccured by additional bytes
// of data supplied with the transaction.
//
// This AnteHandler decorator will fail if:
// - the transaction contains more than one message
// - the message is not a MsgEthereumTx
// - sender account cannot be found
// - transaction's gas limit is lower than the intrinsic gas
// - user doesn't have enough balance to deduct the transaction fees (gas_limit * gas_price)
// - transaction or block gas meter runs out of gas
func (egcd EthGasConsumeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
params := egcd.evmKeeper.GetParams(ctx)
ethCfg := params.ChainConfig.EthereumConfig(egcd.evmKeeper.ChainID())
blockHeight := big.NewInt(ctx.BlockHeight())
homestead := ethCfg.IsHomestead(blockHeight)
istanbul := ethCfg.IsIstanbul(blockHeight)
london := ethCfg.IsLondon(blockHeight)
evmDenom := params.EvmDenom
var events sdk.Events
for _, msg := range tx.GetMsgs() {
msgEthTx, ok := msg.(*evmtypes.MsgEthereumTx)
if !ok {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type %T, expected %T", tx, (*evmtypes.MsgEthereumTx)(nil))
}
txData, err := evmtypes.UnpackTxData(msgEthTx.Data)
if err != nil {
return ctx, sdkerrors.Wrap(err, "failed to unpack tx data")
}
fees, err := egcd.evmKeeper.DeductTxCostsFromUserBalance(
ctx,
*msgEthTx,
txData,
evmDenom,
homestead,
istanbul,
london,
)
if err != nil {
return ctx, sdkerrors.Wrapf(err, "failed to deduct transaction costs from user balance")
}
events = append(events, sdk.NewEvent(sdk.EventTypeTx, sdk.NewAttribute(sdk.AttributeKeyFee, fees.String())))
}
// TODO: change to typed events
ctx.EventManager().EmitEvents(events)
// TODO: deprecate after https://github.com/cosmos/cosmos-sdk/issues/9514 is fixed on SDK
blockGasLimit := ethermint.BlockGasLimit(ctx)
// NOTE: safety check
if blockGasLimit > 0 {
// generate a copy of the gas pool (i.e block gas meter) to see if we've run out of gas for this block
// if current gas consumed is greater than the limit, this funcion panics and the error is recovered on the Baseapp
gasPool := sdk.NewGasMeter(blockGasLimit)
gasPool.ConsumeGas(ctx.GasMeter().GasConsumedToLimit(), "gas pool check")
}
// we know that we have enough gas on the pool to cover the intrinsic gas
return next(ctx, tx, simulate)
}
// CanTransferDecorator checks if the sender is allowed to transfer funds according to the EVM block
// context rules.
type CanTransferDecorator struct {
evmKeeper EVMKeeper
feemarketKeeper evmtypes.FeeMarketKeeper
}
// NewCanTransferDecorator creates a new CanTransferDecorator instance.
func NewCanTransferDecorator(evmKeeper EVMKeeper, fmk evmtypes.FeeMarketKeeper) CanTransferDecorator {
return CanTransferDecorator{
evmKeeper: evmKeeper,
feemarketKeeper: fmk,
}
}
// AnteHandle creates an EVM from the message and calls the BlockContext CanTransfer function to
// see if the address can execute the transaction.
func (ctd CanTransferDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (sdk.Context, error) {
params := ctd.evmKeeper.GetParams(ctx)
ethCfg := params.ChainConfig.EthereumConfig(ctd.evmKeeper.ChainID())
signer := ethtypes.MakeSigner(ethCfg, big.NewInt(ctx.BlockHeight()))
for _, msg := range tx.GetMsgs() {
msgEthTx, ok := msg.(*evmtypes.MsgEthereumTx)
if !ok {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type %T, expected %T", tx, (*evmtypes.MsgEthereumTx)(nil))
}
baseFee := ctd.evmKeeper.BaseFee(ctx, ethCfg)
coreMsg, err := msgEthTx.AsMessage(signer, baseFee)
if err != nil {
return ctx, sdkerrors.Wrapf(
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err,
"failed to create an ethereum core.Message from signer %T", signer,
)
}
// NOTE: pass in an empty coinbase address and nil tracer as we don't need them for the check below
cfg := &evmtypes.EVMConfig{
ChainConfig: ethCfg,
Params: params,
CoinBase: common.Address{},
BaseFee: baseFee,
}
stateDB := statedb.New(ctx, ctd.evmKeeper, statedb.NewEmptyTxConfig(common.BytesToHash(ctx.HeaderHash().Bytes())))
evm := ctd.evmKeeper.NewEVM(ctx, coreMsg, cfg, evmtypes.NewNoOpTracer(), stateDB)
// 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
if coreMsg.Value().Sign() > 0 && !evm.Context.CanTransfer(stateDB, coreMsg.From(), coreMsg.Value()) {
return ctx, sdkerrors.Wrapf(
sdkerrors.ErrInsufficientFunds,
"failed to transfer %s from address %s using the EVM block context transfer function",
coreMsg.Value(),
coreMsg.From(),
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)
}
if evmtypes.IsLondon(ethCfg, ctx.BlockHeight()) {
if baseFee == nil {
return ctx, sdkerrors.Wrap(
evmtypes.ErrInvalidBaseFee,
"base fee is supported but evm block context value is nil",
)
}
if coreMsg.GasFeeCap().Cmp(baseFee) < 0 {
return ctx, sdkerrors.Wrapf(
evmtypes.ErrInvalidBaseFee,
"max fee per gas less than block base fee (%s < %s)",
coreMsg.GasFeeCap(), baseFee,
)
}
}
}
return next(ctx, tx, simulate)
}
// EthIncrementSenderSequenceDecorator increments the sequence of the signers.
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type EthIncrementSenderSequenceDecorator struct {
ak evmtypes.AccountKeeper
}
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// NewEthIncrementSenderSequenceDecorator creates a new EthIncrementSenderSequenceDecorator.
func NewEthIncrementSenderSequenceDecorator(ak evmtypes.AccountKeeper) EthIncrementSenderSequenceDecorator {
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return EthIncrementSenderSequenceDecorator{
ak: ak,
}
}
// AnteHandle handles incrementing the sequence of the signer (i.e sender). If the transaction is a
// contract creation, the nonce will be incremented during the transaction execution and not within
// this AnteHandler decorator.
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func (issd EthIncrementSenderSequenceDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (sdk.Context, error) {
for _, msg := range tx.GetMsgs() {
// increment sequence of all signers
for _, addr := range msg.GetSigners() {
acc := issd.ak.GetAccount(ctx, addr)
if acc == nil {
return ctx, sdkerrors.Wrapf(
sdkerrors.ErrUnknownAddress,
"account %s (%s) is nil", common.BytesToAddress(addr.Bytes()), addr,
)
}
if err := acc.SetSequence(acc.GetSequence() + 1); err != nil {
return ctx, sdkerrors.Wrapf(err, "failed to set sequence to %d", acc.GetSequence()+1)
}
issd.ak.SetAccount(ctx, acc)
}
}
return next(ctx, tx, simulate)
}
// EthValidateBasicDecorator is adapted from ValidateBasicDecorator from cosmos-sdk, it ignores ErrNoSignatures
type EthValidateBasicDecorator struct {
evmKeeper EVMKeeper
}
// NewEthValidateBasicDecorator creates a new EthValidateBasicDecorator
func NewEthValidateBasicDecorator(ek EVMKeeper) EthValidateBasicDecorator {
return EthValidateBasicDecorator{
evmKeeper: ek,
}
}
// AnteHandle handles basic validation of tx
func (vbd EthValidateBasicDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (sdk.Context, error) {
// no need to validate basic on recheck tx, call next antehandler
if ctx.IsReCheckTx() {
return next(ctx, tx, simulate)
}
err := tx.ValidateBasic()
// ErrNoSignatures is fine with eth tx
if err != nil && !errors.Is(err, sdkerrors.ErrNoSignatures) {
return ctx, sdkerrors.Wrap(err, "tx basic validation failed")
}
// For eth type cosmos tx, some fields should be veified as zero values,
// since we will only verify the signature against the hash of the MsgEthereumTx.Data
if wrapperTx, ok := tx.(protoTxProvider); ok {
protoTx := wrapperTx.GetProtoTx()
body := protoTx.Body
if body.Memo != "" || body.TimeoutHeight != uint64(0) || len(body.NonCriticalExtensionOptions) > 0 {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest,
"for eth tx body Memo TimeoutHeight NonCriticalExtensionOptions should be empty")
}
if len(body.ExtensionOptions) != 1 {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "for eth tx length of ExtensionOptions should be 1")
}
if len(protoTx.GetMsgs()) != 1 {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "only 1 ethereum msg supported per tx")
}
msg := protoTx.GetMsgs()[0]
msgEthTx, ok := msg.(*evmtypes.MsgEthereumTx)
if !ok {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type %T, expected %T", tx, (*evmtypes.MsgEthereumTx)(nil))
}
ethGasLimit := msgEthTx.GetGas()
txData, err := evmtypes.UnpackTxData(msgEthTx.Data)
if err != nil {
return ctx, sdkerrors.Wrap(err, "failed to unpack MsgEthereumTx Data")
}
params := vbd.evmKeeper.GetParams(ctx)
chainID := vbd.evmKeeper.ChainID()
ethCfg := params.ChainConfig.EthereumConfig(chainID)
baseFee := vbd.evmKeeper.BaseFee(ctx, ethCfg)
if baseFee == nil && txData.TxType() == ethtypes.DynamicFeeTxType {
return ctx, sdkerrors.Wrap(ethtypes.ErrTxTypeNotSupported, "dynamic fee tx not supported")
}
ethFeeAmount := sdk.Coins{sdk.NewCoin(params.EvmDenom, sdk.NewIntFromBigInt(txData.Fee()))}
authInfo := protoTx.AuthInfo
if len(authInfo.SignerInfos) > 0 {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "for eth tx AuthInfo SignerInfos should be empty")
}
if authInfo.Fee.Payer != "" || authInfo.Fee.Granter != "" {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "for eth tx AuthInfo Fee payer and granter should be empty")
}
if !authInfo.Fee.Amount.IsEqual(ethFeeAmount) {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "invalid eth tx AuthInfo Fee Amount")
}
if authInfo.Fee.GasLimit != ethGasLimit {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "invalid eth tx AuthInfo Fee GasLimit")
}
sigs := protoTx.Signatures
if len(sigs) > 0 {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "for eth tx Signatures should be empty")
}
}
return next(ctx, tx, simulate)
}
// EthSetupContextDecorator is adapted from SetUpContextDecorator from cosmos-sdk, it ignores gas consumption
// by setting the gas meter to infinite
type EthSetupContextDecorator struct{}
func NewEthSetUpContextDecorator() EthSetupContextDecorator {
return EthSetupContextDecorator{}
}
func (esc EthSetupContextDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
// all transactions must implement GasTx
_, ok := tx.(authante.GasTx)
if !ok {
return newCtx, sdkerrors.Wrap(sdkerrors.ErrTxDecode, "Tx must be GasTx")
}
newCtx = ctx.WithGasMeter(sdk.NewInfiniteGasMeter())
return next(newCtx, tx, simulate)
}
// EthMempoolFeeDecorator will check if the transaction's effective fee is at least as large
// as the local validator's minimum gasFee (defined in validator config).
// If fee is too low, decorator returns error and tx is rejected from mempool.
// Note this only applies when ctx.CheckTx = true
// If fee is high enough or not CheckTx, then call next AnteHandler
// CONTRACT: Tx must implement FeeTx to use MempoolFeeDecorator
type EthMempoolFeeDecorator struct {
feemarketKeeper evmtypes.FeeMarketKeeper
evmKeeper EVMKeeper
}
func NewEthMempoolFeeDecorator(ek EVMKeeper, fmk evmtypes.FeeMarketKeeper) EthMempoolFeeDecorator {
return EthMempoolFeeDecorator{
feemarketKeeper: fmk,
evmKeeper: ek,
}
}
// AnteHandle ensures that the provided fees meet a minimum threshold for the validator,
// if this is a CheckTx. This is only for local mempool purposes, and thus
// is only ran on check tx.
func (mfd EthMempoolFeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
if ctx.IsCheckTx() && !simulate {
if len(tx.GetMsgs()) != 1 {
return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "only 1 ethereum msg supported per tx")
}
msg, ok := tx.GetMsgs()[0].(*evmtypes.MsgEthereumTx)
if !ok {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type %T, expected %T", tx, (*evmtypes.MsgEthereumTx)(nil))
}
var feeAmt *big.Int
params := mfd.evmKeeper.GetParams(ctx)
chainID := mfd.evmKeeper.ChainID()
ethCfg := params.ChainConfig.EthereumConfig(chainID)
evmDenom := params.EvmDenom
baseFee := mfd.evmKeeper.BaseFee(ctx, ethCfg)
if baseFee != nil {
feeAmt = msg.GetEffectiveFee(baseFee)
} else {
feeAmt = msg.GetFee()
}
glDec := sdk.NewDec(int64(msg.GetGas()))
requiredFee := ctx.MinGasPrices().AmountOf(evmDenom).Mul(glDec)
if sdk.NewDecFromBigInt(feeAmt).LT(requiredFee) {
return ctx, sdkerrors.Wrapf(sdkerrors.ErrInsufficientFee, "insufficient fees; got: %s required: %s", feeAmt, requiredFee)
}
}
return next(ctx, tx, simulate)
}