feat: zero gas fee

app/ante/handler_options.go

@@ -16,6 +16,8 @@
 package ante
 
 import (
+	"math/big"
+
 	errorsmod "cosmossdk.io/errors"
 	storetypes "cosmossdk.io/store/types"
 	txsigning "cosmossdk.io/x/tx/signing"
@@ -92,6 +94,35 @@ func newEthAnteHandler(options HandlerOptions) sdk.AnteHandler {
 		baseFee := blockCfg.BaseFee
 		rules := blockCfg.Rules
 
+		isZeroGas := false
+		fromAddrs := make([]sdk.AccAddress, 0)
+		for _, m := range tx.GetMsgs() {
+			msgEthTx, ok := m.(*evmtypes.MsgEthereumTx)
+			if !ok {
+				return ctx, errorsmod.Wrapf(errortypes.ErrUnknownRequest, "invalid message type %T, expected %T", m, (*evmtypes.MsgEthereumTx)(nil))
+			}
+			msg := msgEthTx.AsMessage(nil)
+
+			fromAddrs = append(fromAddrs, msg.From.Bytes())
+
+			if msg.To != nil && len(msg.Data) >= 4 {
+				toAddr := msg.To.Bytes()
+				signature := msg.Data[:4]
+				if options.EvmKeeper.HasZeroGas(ctx, toAddr, signature) {
+					isZeroGas = true
+				}
+			}
+		}
+		if isZeroGas {
+			for _, fromAddr := range fromAddrs {
+				if options.AccountKeeper.GetAccount(ctx, fromAddr) == nil {
+					newAcc := options.AccountKeeper.NewAccountWithAddress(ctx, fromAddr)
+					options.AccountKeeper.SetAccount(ctx, newAcc)
+				}
+			}
+			baseFee = big.NewInt(0)
+		}
+
 		// all transactions must implement FeeTx
 		_, ok := tx.(sdk.FeeTx)
 		if !ok {

app/ante/interfaces.go

@@ -33,6 +33,7 @@ type EVMKeeper interface {
 	ChainID() *big.Int
 	EVMBlockConfig(sdk.Context, *big.Int) (*evmkeeper.EVMBlockConfig, error)
 
+	HasZeroGas(ctx sdk.Context, addr []byte, sig []byte) bool
 	DeductTxCostsFromUserBalance(ctx sdk.Context, fees sdk.Coins, from common.Address) error
 }
 

proto/ethermint/evm/v1/genesis.proto

@@ -2,6 +2,7 @@ syntax = "proto3";
 package ethermint.evm.v1;
 
 import "ethermint/evm/v1/params.proto";
+import "ethermint/evm/v1/zero_gas.proto";
 import "ethermint/evm/v1/state.proto";
 import "gogoproto/gogo.proto";
 
@@ -13,6 +14,8 @@ message GenesisState {
   repeated GenesisAccount accounts = 1 [(gogoproto.nullable) = false];
   // params defines all the parameters of the module.
   Params params = 2 [(gogoproto.nullable) = false];
+  // zero_gas defines the zero gas config for the module.
+  repeated ZeroGas zero_gas = 3 [(gogoproto.nullable) = false];
 }
 
 // GenesisAccount defines an account to be initialized in the genesis state.

proto/ethermint/evm/v1/query.proto

@@ -6,6 +6,7 @@ import "ethermint/evm/v1/tx.proto";
 import "ethermint/evm/v1/log.proto";
 import "ethermint/evm/v1/params.proto";
 import "ethermint/evm/v1/trace_config.proto";
+import "ethermint/evm/v1/zero_gas.proto";
 import "gogoproto/gogo.proto";
 import "google/api/annotations.proto";
 import "google/protobuf/timestamp.proto";
@@ -81,6 +82,16 @@ service Query {
   rpc BaseFee(QueryBaseFeeRequest) returns (QueryBaseFeeResponse) {
     option (google.api.http).get = "/ethermint/evm/v1/base_fee";
   }
+
+  // ZeroGas queries the zero gas config for a given contract address and signature
+  rpc ZeroGas(QueryZeroGasRequest) returns (QueryZeroGasResponse) {
+    option (google.api.http).get = "/ethermint/evm/v1/zero_gas";
+  }
+
+  // AllZeroGas queries all the zero gas
+  rpc AllZeroGas(QueryAllZeroGasRequest) returns (QueryAllZeroGasResponse) {
+    option (google.api.http).get = "/ethermint/evm/v1/all_zero_gas";
+  }
 }
 
 // QueryAccountRequest is the request type for the Query/Account RPC method.
@@ -336,3 +347,24 @@ message QueryBaseFeeResponse {
   // base_fee is the EIP1559 base fee
   string base_fee = 1 [(gogoproto.customtype) = "cosmossdk.io/math.Int"];
 }
+
+// QueryZeroGasRequest defines ZeroGas request
+message QueryZeroGasRequest {
+  // contract_address is the contract address to query the zero gas for
+  string contract_address = 1;
+}
+
+// QueryZeroGasResponse defines ZeroGas response
+message QueryZeroGasResponse {
+  // items is the zero gas items
+  repeated string signatures = 1;
+}
+
+// QueryAllZeroGasRequest defines AllZeroGas request
+message QueryAllZeroGasRequest {}
+
+// QueryAllZeroGasResponse defines AllZeroGas response
+message QueryAllZeroGasResponse {
+  // items is the zero gas items
+  repeated ZeroGas items = 1 [ (gogoproto.nullable) = false ];
+}

proto/ethermint/evm/v1/tx.proto

@@ -6,9 +6,11 @@ import "cosmos_proto/cosmos.proto";
 import "gogoproto/gogo.proto";
 import "google/api/annotations.proto";
 import "google/protobuf/any.proto";
+import "amino/amino.proto";
 import "ethermint/evm/v1/access_tuple.proto";
 import "ethermint/evm/v1/log.proto";
 import "ethermint/evm/v1/params.proto";
+import "ethermint/evm/v1/zero_gas.proto";
 
 option go_package = "github.com/evmos/ethermint/x/evm/types";
 
@@ -22,6 +24,8 @@ service Msg {
   // UpdateParams defined a governance operation for updating the x/evm module parameters.
   // The authority is hard-coded to the Cosmos SDK x/gov module account
   rpc UpdateParams(MsgUpdateParams) returns (MsgUpdateParamsResponse);
+  // UpdateZeroGas defines a method for updating the zero gas config
+  rpc UpdateZeroGas(MsgUpdateZeroGas) returns (MsgUpdateZeroGasResponse);
 }
 
 // MsgEthereumTx encapsulates an Ethereum transaction as an SDK message.
@@ -187,3 +191,22 @@ message MsgUpdateParams {
 // MsgUpdateParamsResponse defines the response structure for executing a
 // MsgUpdateParams message.
 message MsgUpdateParamsResponse {}
+
+// MsgUpdateZeroGas defines a Msg for updating the x/evm module zero gas config.
+message MsgUpdateZeroGas {
+  option (cosmos.msg.v1.signer) = "authority";
+
+  // authority is the address that controls the module (defaults to x/gov unless
+  // overwritten).
+  string authority = 1 [ (cosmos_proto.scalar) = "cosmos.AddressString" ];
+  option (amino.name) = "basechain/MsgUpdateZeroGasConfig";
+
+  option (gogoproto.equal) = false;
+
+  // metadata defines the zero gas to update.
+  UpdateZeroGasMetadata metadata = 2 [(gogoproto.nullable) = false];
+}
+
+// MsgUpdateZeroGasResponse defines the response structure for executing a
+// MsgUpdateZeroGas message.
+message MsgUpdateZeroGasResponse {}

proto/ethermint/evm/v1/zero_gas.proto

@@ -0,0 +1,23 @@
+syntax = "proto3";
+package ethermint.evm.v1;
+
+import "gogoproto/gogo.proto";
+
+option go_package = "github.com/evmos/ethermint/x/evm/types";
+
+// ZeroGas defines the parameters for zero gas fee transactions
+message ZeroGas {
+  // contract_address specifies the target contract address for zero gas fee transactions
+  string contract_address = 1 [(gogoproto.moretags) = "yaml:\"contract_address\""];
+  // signatures is a list of function signatures that will have zero gas fee
+  // when called on the specified contract_address
+  repeated string signatures = 2 [(gogoproto.moretags) = "yaml:\"signatures\""];
+}
+
+message UpdateZeroGasMetadata {
+  // zero gas items to be added
+  repeated ZeroGas add_items = 1;
+
+  // zero gas items to be removed
+  repeated ZeroGas remove_items = 2;
+}

x/evm/client/cli/query.go

@@ -39,6 +39,8 @@ func GetQueryCmd() *cobra.Command {
 		GetStorageCmd(),
 		GetCodeCmd(),
 		GetParamsCmd(),
+		GetZeroGasCmd(),
+		GetAllZeroGasCmd(),
 	)
 	return cmd
 }
@@ -147,3 +149,59 @@ func GetParamsCmd() *cobra.Command {
 	flags.AddQueryFlagsToCmd(cmd)
 	return cmd
 }
+
+// GetZeroGasCmd queries the zero gas for a given contract address
+func GetZeroGasCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "zero-gas ADDRESS",
+		Short: "Get the zero gas for a given contract address",
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			clientCtx, err := client.GetClientQueryContext(cmd)
+			if err != nil {
+				return err
+			}
+
+			queryClient := types.NewQueryClient(clientCtx)
+
+			res, err := queryClient.ZeroGas(cmd.Context(), &types.QueryZeroGasRequest{
+				ContractAddress: args[0],
+			})
+			if err != nil {
+				return err
+			}
+
+			return clientCtx.PrintProto(res)
+		},
+	}
+
+	flags.AddQueryFlagsToCmd(cmd)
+	return cmd
+}
+
+// GetAllZeroGasCmd queries the all zero gas for a given contract address
+func GetAllZeroGasCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "all-zero-gas",
+		Short: "Get the all zero gas",
+		Args:  cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, _ []string) error {
+			clientCtx, err := client.GetClientQueryContext(cmd)
+			if err != nil {
+				return err
+			}
+
+			queryClient := types.NewQueryClient(clientCtx)
+
+			res, err := queryClient.AllZeroGas(cmd.Context(), &types.QueryAllZeroGasRequest{})
+			if err != nil {
+				return err
+			}
+
+			return clientCtx.PrintProto(res)
+		},
+	}
+
+	flags.AddQueryFlagsToCmd(cmd)
+	return cmd
+}

x/evm/genesis.go

@@ -82,6 +82,25 @@ func InitGenesis(
 		}
 	}
 
+	for _, config := range data.ZeroGas {
+		if !common.IsHexAddress(config.ContractAddress) {
+			panic(fmt.Sprintf("invalid contract address: %s", config.ContractAddress))
+		}
+
+		contractAddr := common.FromHex(config.ContractAddress)
+		for _, s := range config.Signatures {
+			sig := common.FromHex(s)
+			if len(sig) != 4 {
+				panic(fmt.Sprintf("invalid signature: %s", s))
+			}
+
+			err = k.SetZeroGas(ctx, contractAddr, sig)
+			if err != nil {
+				panic(fmt.Errorf("error setting zero gas config %s", err))
+			}
+		}
+	}
+
 	return []abci.ValidatorUpdate{}
 }
 
@@ -112,5 +131,6 @@ func ExportGenesis(ctx sdk.Context, k *keeper.Keeper, ak types.AccountKeeper) *t
 	return &types.GenesisState{
 		Accounts: ethGenAccounts,
 		Params:   k.GetParams(ctx),
+		ZeroGas:  k.GetAllZeroGas(ctx),
 	}
 }

x/evm/keeper/grpc_query.go

@@ -767,3 +767,23 @@ func getChainID(ctx sdk.Context, chainID int64) (*big.Int, error) {
 	}
 	return big.NewInt(chainID), nil
 }
+
+// ZeroGas implements the Query/ZeroGas gRPC method
+func (k Keeper) ZeroGas(c context.Context, req *types.QueryZeroGasRequest) (*types.QueryZeroGasResponse, error) {
+	ctx := sdk.UnwrapSDKContext(c)
+
+	if !common.IsHexAddress(req.ContractAddress) {
+		return nil, status.Errorf(codes.Internal, "invalid contract address: %s", req.ContractAddress)
+	}
+
+	contractAddr := common.FromHex(req.ContractAddress)
+	sigs := k.GetAllZeroGasSigsByAddr(ctx, contractAddr)
+	return &types.QueryZeroGasResponse{Signatures: sigs}, nil
+}
+
+// AllZeroGas implements the Query/AllZeroGas gRPC method
+func (k Keeper) AllZeroGas(c context.Context, req *types.QueryAllZeroGasRequest) (*types.QueryAllZeroGasResponse, error) {
+	ctx := sdk.UnwrapSDKContext(c)
+	items := k.GetAllZeroGas(ctx)
+	return &types.QueryAllZeroGasResponse{Items: items}, nil
+}