Merge pull request #49 from bze-alphateam/feature/tx-ante

added ante handler to reject txes with fees in unknown denoms

app/ante.go

@@ -0,0 +1,87 @@
+package app
+
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	"github.com/cosmos/cosmos-sdk/x/auth/ante"
+)
+
+const (
+	denomMainnet = "ubze"
+	denomTestnet = "utbz"
+)
+
+func NewAnteHandler(options ante.HandlerOptions) (sdk.AnteHandler, error) {
+	if options.AccountKeeper == nil {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrLogic, "account keeper is required for ante builder")
+	}
+
+	if options.BankKeeper == nil {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrLogic, "bank keeper is required for ante builder")
+	}
+
+	if options.SignModeHandler == nil {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrLogic, "sign mode handler is required for ante builder")
+	}
+
+	sigGasConsumer := options.SigGasConsumer
+	if sigGasConsumer == nil {
+		sigGasConsumer = ante.DefaultSigVerificationGasConsumer
+	}
+
+	anteDecorators := []sdk.AnteDecorator{
+		ante.NewSetUpContextDecorator(), // outermost AnteDecorator. SetUpContext must be called first
+		ante.NewRejectExtensionOptionsDecorator(),
+		ante.NewMempoolFeeDecorator(),
+		ante.NewValidateBasicDecorator(),
+		NewValidateTxFeeDenomsDecorator(), //use our own validate basic to enforce denoms that should be used for fees
+		ante.NewTxTimeoutHeightDecorator(),
+		ante.NewValidateMemoDecorator(options.AccountKeeper),
+		ante.NewConsumeGasForTxSizeDecorator(options.AccountKeeper),
+		ante.NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper),
+		ante.NewSetPubKeyDecorator(options.AccountKeeper), // SetPubKeyDecorator must be called before all signature verification decorators
+		ante.NewValidateSigCountDecorator(options.AccountKeeper),
+		ante.NewSigGasConsumeDecorator(options.AccountKeeper, sigGasConsumer),
+		ante.NewSigVerificationDecorator(options.AccountKeeper, options.SignModeHandler),
+		ante.NewIncrementSequenceDecorator(options.AccountKeeper),
+	}
+
+	return sdk.ChainAnteDecorators(anteDecorators...), nil
+}
+
+// ValidateTxFeeDenomsDecorator will check if denominations used for tx fees are allowed and returns an error otherwise
+type ValidateTxFeeDenomsDecorator struct{}
+
+func NewValidateTxFeeDenomsDecorator() ValidateTxFeeDenomsDecorator {
+	return ValidateTxFeeDenomsDecorator{}
+}
+
+func (vbd ValidateTxFeeDenomsDecorator) 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)
+	}
+
+	feeTx, ok := tx.(sdk.FeeTx)
+	if !ok {
+		return ctx, sdkerrors.Wrap(sdkerrors.ErrTxDecode, "ValidateTxFeeDenomsDecorator requires tx to be a FeeTx")
+	}
+
+	for _, c := range feeTx.GetFee() {
+		if !vbd.isAllowedDenom(c.Denom) {
+			return ctx, sdkerrors.Wrapf(
+				sdkerrors.ErrInvalidRequest,
+				"invalid fee supplied. cannot pay fee in %s denomination. Allowed denomination is %s for mainnet and %s for testnet",
+				c.Denom,
+				denomMainnet,
+				denomTestnet,
+			)
+		}
+	}
+
+	return next(ctx, tx, simulate)
+}
+
+func (vbd ValidateTxFeeDenomsDecorator) isAllowedDenom(denom string) bool {
+	return denom == denomMainnet || denom == denomTestnet
+}

app/app.go

@@ -678,7 +678,7 @@ func New(
 	app.SetInitChainer(app.InitChainer)
 	app.SetBeginBlocker(app.BeginBlocker)
 
-	anteHandler, err := ante.NewAnteHandler(
+	anteHandler, err := NewAnteHandler(
 		ante.HandlerOptions{
 			AccountKeeper:   app.AccountKeeper,
 			BankKeeper:      app.BankKeeper,

go.mod

@@ -16,6 +16,7 @@ require (
 	github.com/stretchr/testify v1.8.1
 	github.com/tendermint/tendermint v0.34.27
 	github.com/tendermint/tm-db v0.6.7
+	google.golang.org/genproto/googleapis/api v0.0.0-20240814211410-ddb44dafa142
 	google.golang.org/genproto/googleapis/api v0.0.0-20240723171418-e6d459c13d2a
 	google.golang.org/grpc v1.64.1
 	google.golang.org/protobuf v1.34.2