Prefer sending tx_bytes to Simulate gRPC endpoint (#8926)

* First run * Remove dead code * Make test pass * Proto gen * Fix lint * Add changelog * Fix tests * Fix test * Update x/auth/tx/service.go Co-authored-by: Marie Gauthier <marie.gauthier63@gmail.com> * Remove protoTxProvider * Add grpc-gateway test * Add comment * move to api breaking * lesser diff * remove conflict * empty commit to rerun CI * empty commit to rerun CI Co-authored-by: Marie Gauthier <marie.gauthier63@gmail.com> Co-authored-by: Alessio Treglia <alessio@tendermint.com> Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
2021-03-25 11:52:54 +01:00 · 2021-03-25 11:52:54 +01:00 · 1fa2c22d8a
commit 1fa2c22d8a
parent 7ac436d2f7
14 changed files with 809 additions and 751 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -65,6 +65,8 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (x/upgrade) [\#8743](https://github.com/cosmos/cosmos-sdk/pull/8743) `UpgradeHandler` includes a new argument `VersionMap` which helps facilitate in-place migrations.
 * (x/auth) [\#8129](https://github.com/cosmos/cosmos-sdk/pull/8828) Updated `SigVerifiableTx.GetPubKeys` method signature to return error.
 * [\#8682](https://github.com/cosmos/cosmos-sdk/pull/8682) `ante.NewAnteHandler` updated to receive all positional params as `ante.HandlerOptions` struct. If required fields aren't set, throws error accordingly.
+* (client) [\#8926](https://github.com/cosmos/cosmos-sdk/pull/8926) `client/tx.PrepareFactory` has been converted to a private function, as it's only used internally.
+* (auth/tx) [\#8926](https://github.com/cosmos/cosmos-sdk/pull/8926) The `ProtoTxProvider` interface used as a workaround for transaction simulation has been removed.

 ### State Machine Breaking

@ -110,6 +112,10 @@ Ref: https://keepachangelog.com/en/1.0.0/

 This release fixes security vulnerability identified in the simapp.

+### Deprecated
+
+* (grpc) [\#8926](https://github.com/cosmos/cosmos-sdk/pull/8926) The `tx` field in `SimulateRequest` has been deprecated, prefer to pass `tx_bytes` instead.
+
 ## [v0.42.0](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.42.0) - 2021-03-08

 **IMPORTANT**: This release contains an important security fix for all non Cosmos Hub chains running Stargate version of the Cosmos SDK (>0.40). Non-hub chains should not be using any version of the SDK in the v0.40.x or v0.41.x release series. See [#8461](https://github.com/cosmos/cosmos-sdk/pull/8461) for more details.
--- a/client/tx/tx.go
+++ b/client/tx/tx.go
@ -2,11 +2,13 @@ package tx

 import (
 	"bufio"
+	"context"
 	"errors"
 	"fmt"
 	"net/http"
 	"os"

+	gogogrpc "github.com/gogo/protobuf/grpc"
 	"github.com/spf13/pflag"

 	"github.com/cosmos/cosmos-sdk/client"
@ -20,7 +22,6 @@ import (
 	"github.com/cosmos/cosmos-sdk/types/tx"
 	"github.com/cosmos/cosmos-sdk/types/tx/signing"
 	authsigning "github.com/cosmos/cosmos-sdk/x/auth/signing"
-	authtx "github.com/cosmos/cosmos-sdk/x/auth/tx"
 )

 // GenerateOrBroadcastTxCLI will either generate and print and unsigned transaction
@ -50,7 +51,7 @@ func GenerateTx(clientCtx client.Context, txf Factory, msgs ...sdk.Msg) error {
 			return errors.New("cannot estimate gas in offline mode")
 		}

-		_, adjusted, err := CalculateGas(clientCtx.QueryWithData, txf, msgs...)
+		_, adjusted, err := CalculateGas(clientCtx, txf, msgs...)
 		if err != nil {
 			return err
 		}
@ -76,13 +77,13 @@ func GenerateTx(clientCtx client.Context, txf Factory, msgs ...sdk.Msg) error {
 // given set of messages. It will also simulate gas requirements if necessary.
 // It will return an error upon failure.
 func BroadcastTx(clientCtx client.Context, txf Factory, msgs ...sdk.Msg) error {
-	txf, err := PrepareFactory(clientCtx, txf)
+	txf, err := prepareFactory(clientCtx, txf)
 	if err != nil {
 		return err
 	}

 	if txf.SimulateAndExecute() || clientCtx.Simulate {
-		_, adjusted, err := CalculateGas(clientCtx.QueryWithData, txf, msgs...)
+		_, adjusted, err := CalculateGas(clientCtx, txf, msgs...)
 		if err != nil {
 			return err
 		}
@ -142,8 +143,9 @@ func BroadcastTx(clientCtx client.Context, txf Factory, msgs ...sdk.Msg) error {
 // BaseReq. Upon any error, the error will be written to the http.ResponseWriter.
 // Note that this function returns the legacy StdTx Amino JSON format for compatibility
 // with legacy clients.
+// Deprecated: We are removing Amino soon.
 func WriteGeneratedTxResponse(
-	ctx client.Context, w http.ResponseWriter, br rest.BaseReq, msgs ...sdk.Msg,
+	clientCtx client.Context, w http.ResponseWriter, br rest.BaseReq, msgs ...sdk.Msg,
 ) {
 	gasAdj, ok := rest.ParseFloat64OrReturnBadRequest(w, br.GasAdjustment, flags.DefaultGasAdjustment)
 	if !ok {
@ -163,7 +165,7 @@ func WriteGeneratedTxResponse(
 		WithMemo(br.Memo).
 		WithChainID(br.ChainID).
 		WithSimulateAndExecute(br.Simulate).
-		WithTxConfig(ctx.TxConfig).
+		WithTxConfig(clientCtx.TxConfig).
 		WithTimeoutHeight(br.TimeoutHeight)

 	if br.Simulate || gasSetting.Simulate {
@ -172,7 +174,7 @@ func WriteGeneratedTxResponse(
 			return
 		}

-		_, adjusted, err := CalculateGas(ctx.QueryWithData, txf, msgs...)
+		_, adjusted, err := CalculateGas(clientCtx, txf, msgs...)
 		if rest.CheckInternalServerError(w, err) {
 			return
 		}
@ -180,7 +182,7 @@ func WriteGeneratedTxResponse(
 		txf = txf.WithGas(adjusted)

 		if br.Simulate {
-			rest.WriteSimulationResponse(w, ctx.LegacyAmino, txf.Gas())
+			rest.WriteSimulationResponse(w, clientCtx.LegacyAmino, txf.Gas())
 			return
 		}
 	}
@ -190,12 +192,12 @@ func WriteGeneratedTxResponse(
 		return
 	}

-	stdTx, err := ConvertTxToStdTx(ctx.LegacyAmino, tx.GetTx())
+	stdTx, err := ConvertTxToStdTx(clientCtx.LegacyAmino, tx.GetTx())
 	if rest.CheckInternalServerError(w, err) {
 		return
 	}

-	output, err := ctx.LegacyAmino.MarshalJSON(stdTx)
+	output, err := clientCtx.LegacyAmino.MarshalJSON(stdTx)
 	if rest.CheckInternalServerError(w, err) {
 		return
 	}
@ -268,46 +270,35 @@ func BuildSimTx(txf Factory, msgs ...sdk.Msg) ([]byte, error) {
 		return nil, err
 	}

-	protoProvider, ok := txb.(authtx.ProtoTxProvider)
-	if !ok {
-		return nil, fmt.Errorf("cannot simulate amino tx")
-	}
-	simReq := tx.SimulateRequest{Tx: protoProvider.GetProtoTx()}
-
-	return simReq.Marshal()
+	return txf.txConfig.TxEncoder()(txb.GetTx())
 }

 // CalculateGas simulates the execution of a transaction and returns the
 // simulation response obtained by the query and the adjusted gas amount.
 func CalculateGas(
-	queryFunc func(string, []byte) ([]byte, int64, error), txf Factory, msgs ...sdk.Msg,
-) (tx.SimulateResponse, uint64, error) {
+	clientCtx gogogrpc.ClientConn, txf Factory, msgs ...sdk.Msg,
+) (*tx.SimulateResponse, uint64, error) {
 	txBytes, err := BuildSimTx(txf, msgs...)
 	if err != nil {
-		return tx.SimulateResponse{}, 0, err
+		return nil, 0, err
 	}

-	// TODO This should use the generated tx service Client.
-	// https://github.com/cosmos/cosmos-sdk/issues/7726
-	bz, _, err := queryFunc("/cosmos.tx.v1beta1.Service/Simulate", txBytes)
+	txSvcClient := tx.NewServiceClient(clientCtx)
+	simRes, err := txSvcClient.Simulate(context.Background(), &tx.SimulateRequest{
+		TxBytes: txBytes,
+	})
 	if err != nil {
-		return tx.SimulateResponse{}, 0, err
-	}
-
-	var simRes tx.SimulateResponse
-
-	if err := simRes.Unmarshal(bz); err != nil {
-		return tx.SimulateResponse{}, 0, err
+		return nil, 0, err
 	}

 	return simRes, uint64(txf.GasAdjustment() * float64(simRes.GasInfo.GasUsed)), nil
 }

-// PrepareFactory ensures the account defined by ctx.GetFromAddress() exists and
+// prepareFactory ensures the account defined by ctx.GetFromAddress() exists and
 // if the account number and/or the account sequence number are zero (not set),
 // they will be queried for and set on the provided Factory. A new Factory with
 // the updated fields will be returned.
-func PrepareFactory(clientCtx client.Context, txf Factory) (Factory, error) {
+func prepareFactory(clientCtx client.Context, txf Factory) (Factory, error) {
 	from := clientCtx.GetFromAddress()

 	if err := txf.accountRetriever.EnsureExists(clientCtx, from); err != nil {
--- a/client/tx/tx_test.go
+++ b/client/tx/tx_test.go
@ -1,10 +1,12 @@
 package tx_test

 import (
-	"errors"
+	gocontext "context"
+	"fmt"
 	"testing"

 	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc"

 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/tx"
@ -24,30 +26,34 @@ func NewTestTxConfig() client.TxConfig {
 	return cfg.TxConfig
 }

-func TestCalculateGas(t *testing.T) {
-	makeQueryFunc := func(gasUsed uint64, wantErr bool) func(string, []byte) ([]byte, int64, error) {
-		return func(string, []byte) ([]byte, int64, error) {
-			if wantErr {
-				return nil, 0, errors.New("query failed")
-			}
-			simRes := &txtypes.SimulateResponse{
-				GasInfo: &sdk.GasInfo{GasUsed: gasUsed, GasWanted: gasUsed},
-				Result:  &sdk.Result{Data: []byte("tx data"), Log: "log"},
-			}
+// mockContext is a mock client.Context to return abitrary simulation response, used to
+// unit test CalculateGas.
+type mockContext struct {
+	gasUsed uint64
+	wantErr bool
+}

-			bz, err := simRes.Marshal()
-			if err != nil {
-				return nil, 0, err
-			}
-
-			return bz, 0, nil
-		}
+func (m mockContext) Invoke(grpcCtx gocontext.Context, method string, req, reply interface{}, opts ...grpc.CallOption) (err error) {
+	if m.wantErr {
+		return fmt.Errorf("mock err")
 	}

+	*(reply.(*txtypes.SimulateResponse)) = txtypes.SimulateResponse{
+		GasInfo: &sdk.GasInfo{GasUsed: m.gasUsed, GasWanted: m.gasUsed},
+		Result:  &sdk.Result{Data: []byte("tx data"), Log: "log"},
+	}
+
+	return nil
+}
+func (mockContext) NewStream(gocontext.Context, *grpc.StreamDesc, string, ...grpc.CallOption) (grpc.ClientStream, error) {
+	panic("not implemented")
+}
+
+func TestCalculateGas(t *testing.T) {
 	type args struct {
-		queryFuncGasUsed uint64
-		queryFuncWantErr bool
-		adjustment       float64
+		mockGasUsed uint64
+		mockWantErr bool
+		adjustment  float64
 	}

 	testCases := []struct {
@ -70,8 +76,11 @@ func TestCalculateGas(t *testing.T) {
 			WithTxConfig(txCfg).WithSignMode(txCfg.SignModeHandler().DefaultMode())

 		t.Run(stc.name, func(t *testing.T) {
-			queryFunc := makeQueryFunc(stc.args.queryFuncGasUsed, stc.args.queryFuncWantErr)
-			simRes, gotAdjusted, err := tx.CalculateGas(queryFunc, txf.WithGasAdjustment(stc.args.adjustment))
+			mockClientCtx := mockContext{
+				gasUsed: tc.args.mockGasUsed,
+				wantErr: tc.args.mockWantErr,
+			}
+			simRes, gotAdjusted, err := tx.CalculateGas(mockClientCtx, txf.WithGasAdjustment(stc.args.adjustment))
 			if stc.expPass {
 				require.NoError(t, err)
 				require.Equal(t, simRes.GasInfo.GasUsed, stc.wantEstimate)
@ -79,7 +88,7 @@ func TestCalculateGas(t *testing.T) {
 				require.NotNil(t, simRes.Result)
 			} else {
 				require.Error(t, err)
-				require.Nil(t, simRes.Result)
+				require.Nil(t, simRes)
 			}
 		})
 	}
--- a/docs/core/proto-docs.md
+++ b/docs/core/proto-docs.md
@ -7257,7 +7257,8 @@ RPC method.

 | Field | Type | Label | Description |
 | ----- | ---- | ----- | ----------- |
-| `tx` | [Tx](#cosmos.tx.v1beta1.Tx) |  | tx is the transaction to simulate. |
+| `tx` | [Tx](#cosmos.tx.v1beta1.Tx) |  | **Deprecated.** tx is the transaction to simulate. Deprecated. Send raw tx bytes instead. |
+| `tx_bytes` | [bytes](#bytes) |  | tx_bytes is the raw transaction. |



--- a/docs/run-node/txs.md
+++ b/docs/run-node/txs.md
@ -305,15 +305,13 @@ func simulateTx() error {
    // Simulate the tx via gRPC. We create a new client for the Protobuf Tx
    // service.
    txClient := tx.NewServiceClient(grpcConn)
-    // We then call the BroadcastTx method on this client.
-    protoTx := txBuilderToProtoTx(txBuilder)
-    if err != nil {
-        return err
-    }
+    txBytes := /* Fill in with your signed transaction bytes. */
+
+    // We then call the Simulate method on this client.
    grpcRes, err := txClient.Simulate(
        context.Background(),
        &tx.SimulateRequest{
-            Tx: protoTx,
+            TxBytes: txBytes,
        },
    )
    if err != nil {
@ -324,16 +322,6 @@ func simulateTx() error {

    return nil
 }
-
-// txBuilderToProtoTx converts a txBuilder into a proto tx.Tx.
-func txBuilderToProtoTx(txBuilder client.TxBuilder) (*tx.Tx, error) { // nolint
-	protoProvider, ok := txBuilder.(authtx.ProtoTxProvider)
-	if !ok {
-		return nil, fmt.Errorf("expected proto tx builder, got %T", txBuilder)
-	}
-
-	return protoProvider.GetProtoTx(), nil
-}
 ```

 ## Using REST
--- a/proto/cosmos/tx/v1beta1/service.proto
+++ b/proto/cosmos/tx/v1beta1/service.proto
@ -101,7 +101,10 @@ message BroadcastTxResponse {
 // RPC method.
 message SimulateRequest {
  // tx is the transaction to simulate.
-  cosmos.tx.v1beta1.Tx tx = 1;
+  // Deprecated. Send raw tx bytes instead.
+  cosmos.tx.v1beta1.Tx tx = 1 [deprecated=true];
+  // tx_bytes is the raw transaction.
+  bytes tx_bytes = 2;
 }

 // SimulateResponse is the response type for the
--- a/simapp/simd/cmd/root.go
+++ b/simapp/simd/cmd/root.go
@ -25,7 +25,6 @@ import (
 	"github.com/cosmos/cosmos-sdk/snapshots"
 	"github.com/cosmos/cosmos-sdk/store"
 	sdk "github.com/cosmos/cosmos-sdk/types"
-	authclient "github.com/cosmos/cosmos-sdk/x/auth/client"
 	authcmd "github.com/cosmos/cosmos-sdk/x/auth/client/cli"
 	"github.com/cosmos/cosmos-sdk/x/auth/types"
 	vestingcli "github.com/cosmos/cosmos-sdk/x/auth/vesting/client/cli"
@ -66,8 +65,6 @@ func NewRootCmd() (*cobra.Command, params.EncodingConfig) {
 }

 func initRootCmd(rootCmd *cobra.Command, encodingConfig params.EncodingConfig) {
-	authclient.Codec = encodingConfig.Marshaler
-
 	rootCmd.AddCommand(
 		genutilcli.InitCmd(simapp.ModuleBasics, simapp.DefaultNodeHome),
 		genutilcli.CollectGenTxsCmd(banktypes.GenesisBalancesIterator{}, simapp.DefaultNodeHome),
--- a/types/tx/service.pb.go
+++ b/types/tx/service.pb.go
@ -339,7 +339,10 @@ func (m *BroadcastTxResponse) GetTxResponse() *types.TxResponse {
 // RPC method.
 type SimulateRequest struct {
 	// tx is the transaction to simulate.
-	Tx *Tx `protobuf:"bytes,1,opt,name=tx,proto3" json:"tx,omitempty"`
+	// Deprecated. Send raw tx bytes instead.
+	Tx *Tx `protobuf:"bytes,1,opt,name=tx,proto3" json:"tx,omitempty"` // Deprecated: Do not use.
+	// tx_bytes is the raw transaction.
+	TxBytes []byte `protobuf:"bytes,2,opt,name=tx_bytes,json=txBytes,proto3" json:"tx_bytes,omitempty"`
 }

 func (m *SimulateRequest) Reset()         { *m = SimulateRequest{} }
@ -375,6 +378,7 @@ func (m *SimulateRequest) XXX_DiscardUnknown() {

 var xxx_messageInfo_SimulateRequest proto.InternalMessageInfo

+// Deprecated: Do not use.
 func (m *SimulateRequest) GetTx() *Tx {
 	if m != nil {
 		return m.Tx
@ -382,6 +386,13 @@ func (m *SimulateRequest) GetTx() *Tx {
 	return nil
 }

+func (m *SimulateRequest) GetTxBytes() []byte {
+	if m != nil {
+		return m.TxBytes
+	}
+	return nil
+}
+
 // SimulateResponse is the response type for the
 // Service.SimulateRPC method.
 type SimulateResponse struct {
@ -569,59 +580,59 @@ func init() {
 }

 var fileDescriptor_e0b00a618705eca7 = []byte{
-	// 817 bytes of a gzipped FileDescriptorProto
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-	0x96, 0x91, 0xd0, 0x4b, 0x58, 0x9d, 0xfe, 0x53, 0x6f, 0xb4, 0x6a, 0x19, 0xb9, 0x74, 0x0d, 0xab,
-	0x73, 0x83, 0x82, 0x14, 0xc8, 0x55, 0x8d, 0x66, 0xa5, 0x5e, 0xab, 0xb4, 0x8e, 0xdb, 0x07, 0xcd,
-	0x7a, 0x63, 0x81, 0x35, 0x0b, 0xeb, 0x0b, 0xfb, 0xd5, 0x6f, 0x9a, 0xb5, 0xaf, 0x33, 0x12, 0x7a,
-	0x1f, 0xd6, 0x16, 0x76, 0x5a, 0x27, 0x87, 0xb5, 0x8c, 0x1c, 0x91, 0x52, 0xe1, 0x3b, 0xf1, 0xf2,
-	0xbf, 0x71, 0x48, 0xb4, 0x82, 0xd7, 0x13, 0x5d, 0x41, 0x72, 0x32, 0x02, 0x48, 0x8d, 0x70, 0x70,
-	0x61, 0xb4, 0x72, 0x6f, 0x1f, 0xc4, 0x88, 0x91, 0xdc, 0xfc, 0xe9, 0xcf, 0x7f, 0x7e, 0x95, 0xf3,
-	0xea, 0x6b, 0x3d, 0xe2, 0xd9, 0x16, 0xe0, 0x2f, 0xa4, 0x12, 0xba, 0x80, 0x77, 0xf8, 0x79, 0xa2,
-	0x8d, 0x08, 0xd6, 0xf0, 0x34, 0xe4, 0xf2, 0xcb, 0x01, 0xa2, 0x66, 0x81, 0xd7, 0xdc, 0x40, 0x1f,
-	0xe9, 0x51, 0x6f, 0x36, 0xd5, 0xaf, 0xfc, 0x09, 0xba, 0x41, 0x3f, 0x42, 0x2a, 0x74, 0x17, 0x51,
-	0xe1, 0xa1, 0x2b, 0x3c, 0x2b, 0xbf, 0xf9, 0x18, 0x4c, 0x88, 0x78, 0xc3, 0x45, 0xbc, 0x56, 0x5f,
-	0x45, 0x8b, 0xf0, 0x7b, 0xbe, 0x86, 0x54, 0xe8, 0x15, 0x8d, 0x14, 0x70, 0xff, 0x9b, 0x10, 0x29,
-	0x20, 0xe2, 0x31, 0x56, 0x15, 0x2e, 0x20, 0x8b, 0x96, 0x08, 0xa8, 0xd6, 0xfe, 0xb8, 0x53, 0xa4,
-	0xdb, 0x3b, 0x45, 0xfa, 0xfb, 0x4e, 0x91, 0x7e, 0x19, 0x2b, 0xb1, 0xdf, 0xc7, 0x8a, 0x74, 0x3b,
-	0x56, 0x62, 0x7f, 0x8d, 0x95, 0xd8, 0x77, 0x05, 0xcb, 0x66, 0x67, 0xc3, 0x8e, 0xd6, 0x25, 0xfd,
-	0x49, 0x7e, 0xf0, 0xf3, 0x09, 0xed, 0xfd, 0xa0, 0xb3, 0xd1, 0x00, 0xfb, 0x84, 0x9d, 0x15, 0xfe,
-	0xf9, 0xfa, 0xf4, 0xbf, 0x00, 0x00, 0x00, 0xff, 0xff, 0x7b, 0x64, 0xf5, 0xff, 0x95, 0x07, 0x00,
-	0x00,
+	// 831 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x9c, 0x55, 0x41, 0x8f, 0xdb, 0x44,
+	0x14, 0x5e, 0x3b, 0x65, 0x93, 0xbe, 0x64, 0x4b, 0x3a, 0xbb, 0x14, 0x93, 0x82, 0x37, 0x75, 0xc9,
+	0x36, 0x44, 0xc2, 0x56, 0x03, 0x48, 0x08, 0x71, 0x89, 0x93, 0x74, 0x59, 0x41, 0x9b, 0x6a, 0xb2,
+	0x08, 0x15, 0x21, 0x45, 0x4e, 0x32, 0xf5, 0x5a, 0x6c, 0x3c, 0x59, 0xcf, 0x64, 0xe5, 0xa8, 0xad,
+	0x90, 0x38, 0x72, 0x42, 0xe2, 0x67, 0xf0, 0x27, 0x38, 0x72, 0x5c, 0x89, 0x0b, 0x47, 0xb4, 0xe1,
+	0x47, 0x70, 0x44, 0x1e, 0x4f, 0x12, 0x27, 0xeb, 0x74, 0x11, 0xa7, 0xbc, 0xc9, 0x7c, 0xef, 0x7b,
+	0xdf, 0xfb, 0xe6, 0xcd, 0x18, 0xf6, 0x07, 0x94, 0x8d, 0x28, 0xb3, 0x78, 0x68, 0x9d, 0x3f, 0xec,
+	0x13, 0xee, 0x3c, 0xb4, 0x18, 0x09, 0xce, 0xbd, 0x01, 0x31, 0xc7, 0x01, 0xe5, 0x14, 0xdd, 0x8e,
+	0x01, 0x26, 0x0f, 0x4d, 0x09, 0x28, 0xbd, 0xeb, 0x52, 0xea, 0x9e, 0x12, 0xcb, 0x19, 0x7b, 0x96,
+	0xe3, 0xfb, 0x94, 0x3b, 0xdc, 0xa3, 0x3e, 0x8b, 0x13, 0x4a, 0xf7, 0x25, 0x63, 0xdf, 0x61, 0xc4,
+	0x72, 0xfa, 0x03, 0x6f, 0x41, 0x1c, 0x2d, 0x24, 0xa8, 0x74, 0xb5, 0x2c, 0x0f, 0xe5, 0xde, 0x9e,
+	0x4b, 0x5d, 0x2a, 0x42, 0x2b, 0x8a, 0xe4, 0xbf, 0xb5, 0x24, 0xed, 0xd9, 0x84, 0x04, 0xd3, 0x45,
+	0xe6, 0xd8, 0x71, 0x3d, 0x5f, 0x68, 0x88, 0xb1, 0xc6, 0xaf, 0x0a, 0xa0, 0x43, 0xc2, 0x8f, 0x43,
+	0xd6, 0x3e, 0x27, 0x3e, 0xc7, 0xe4, 0x6c, 0x42, 0x18, 0x47, 0x77, 0x60, 0x9b, 0x44, 0x6b, 0xa6,
+	0x29, 0xe5, 0x4c, 0xf5, 0x26, 0x96, 0x2b, 0xf4, 0x08, 0x60, 0x49, 0xa1, 0xa9, 0x65, 0xa5, 0x9a,
+	0xaf, 0x1f, 0x98, 0xb2, 0xef, 0xa8, 0x9e, 0x29, 0xea, 0xcd, 0xfb, 0x37, 0x9f, 0x3a, 0x2e, 0x91,
+	0x9c, 0x38, 0x91, 0x89, 0x3e, 0x81, 0x1c, 0x0d, 0x86, 0x24, 0xe8, 0xf5, 0xa7, 0x5a, 0xa6, 0xac,
+	0x54, 0x6f, 0xd5, 0x4b, 0xe6, 0x15, 0xf7, 0xcc, 0x4e, 0x04, 0xb1, 0xa7, 0x38, 0x4b, 0xe3, 0xc0,
+	0xb8, 0x50, 0x60, 0x77, 0x45, 0x2d, 0x1b, 0x53, 0x9f, 0x11, 0xf4, 0x00, 0x32, 0x3c, 0x8c, 0xb5,
+	0xe6, 0xeb, 0x6f, 0xa5, 0x30, 0x1d, 0x87, 0x38, 0x42, 0xa0, 0x43, 0x28, 0xf0, 0xb0, 0x17, 0xc8,
+	0x3c, 0xa6, 0xa9, 0x22, 0xe3, 0xfd, 0x95, 0x0e, 0x84, 0xf7, 0x89, 0x44, 0x09, 0xc6, 0x79, 0xbe,
+	0x88, 0x23, 0xa2, 0xa4, 0x11, 0x19, 0x61, 0xc4, 0x83, 0x6b, 0x8d, 0x90, 0x4c, 0x89, 0x54, 0x83,
+	0x00, 0xb2, 0x03, 0xea, 0x0c, 0x07, 0x0e, 0xe3, 0x51, 0xb1, 0xd8, 0xff, 0x77, 0x20, 0xc7, 0xc3,
+	0x5e, 0x7f, 0xca, 0x49, 0xd4, 0x95, 0x52, 0x2d, 0xe0, 0x2c, 0x0f, 0xed, 0x68, 0x89, 0x3e, 0x86,
+	0x1b, 0x23, 0x3a, 0x24, 0xc2, 0xfc, 0x5b, 0xf5, 0x72, 0x4a, 0xb3, 0x0b, 0xbe, 0xc7, 0x74, 0x48,
+	0xb0, 0x40, 0x1b, 0xdf, 0xc1, 0xee, 0x4a, 0x19, 0x69, 0x5c, 0x1b, 0xf2, 0x09, 0x3f, 0x44, 0xa9,
+	0xff, 0x6a, 0x07, 0x2c, 0xed, 0x30, 0xbe, 0x81, 0x37, 0xbb, 0xde, 0x68, 0x72, 0xea, 0xf0, 0xf9,
+	0x69, 0xa3, 0x0f, 0x40, 0xe5, 0xa1, 0x24, 0x4c, 0x3f, 0x11, 0x5b, 0xd5, 0x14, 0xac, 0xf2, 0x70,
+	0xa5, 0x59, 0x75, 0xa5, 0x59, 0xe3, 0x27, 0x05, 0x8a, 0x4b, 0x66, 0x29, 0xfa, 0x73, 0xc8, 0xb9,
+	0x0e, 0xeb, 0x79, 0xfe, 0x73, 0x2a, 0x0b, 0xdc, 0xdb, 0xac, 0xf8, 0xd0, 0x61, 0x47, 0xfe, 0x73,
+	0x8a, 0xb3, 0x6e, 0x1c, 0xa0, 0x4f, 0x61, 0x3b, 0x20, 0x6c, 0x72, 0xca, 0xe5, 0xf8, 0x96, 0x37,
+	0xe7, 0x62, 0x81, 0xc3, 0x12, 0x6f, 0x18, 0x50, 0x10, 0xc3, 0x37, 0x6f, 0x11, 0xc1, 0x8d, 0x13,
+	0x87, 0x9d, 0x08, 0x0d, 0x37, 0xb1, 0x88, 0x8d, 0x57, 0xb0, 0x23, 0x31, 0x52, 0x6c, 0xe5, 0x5a,
+	0x1f, 0x84, 0x07, 0x6b, 0x07, 0xa1, 0xfe, 0xbf, 0x83, 0xa8, 0x7d, 0x01, 0x59, 0x79, 0x69, 0x90,
+	0x06, 0x7b, 0x1d, 0xdc, 0x6a, 0xe3, 0x9e, 0xfd, 0xac, 0xf7, 0xf5, 0x93, 0xee, 0xd3, 0x76, 0xf3,
+	0xe8, 0xd1, 0x51, 0xbb, 0x55, 0xdc, 0x42, 0x45, 0x28, 0x2c, 0x76, 0x1a, 0xdd, 0x66, 0x51, 0x41,
+	0xb7, 0x61, 0x67, 0xf1, 0x4f, 0xab, 0xdd, 0x6d, 0x16, 0xd5, 0xda, 0x4b, 0xd8, 0x59, 0x99, 0x23,
+	0xa4, 0x43, 0xc9, 0xc6, 0x9d, 0x46, 0xab, 0xd9, 0xe8, 0x1e, 0xf7, 0x1e, 0x77, 0x5a, 0xed, 0x35,
+	0x56, 0x0d, 0xf6, 0xd6, 0xf6, 0xed, 0xaf, 0x3a, 0xcd, 0x2f, 0x8b, 0x0a, 0x7a, 0x1b, 0x76, 0xd7,
+	0x76, 0xba, 0xcf, 0x9e, 0x34, 0x8b, 0x6a, 0x4a, 0x4a, 0x43, 0xec, 0x64, 0xea, 0xff, 0x64, 0x20,
+	0xdb, 0x8d, 0x1f, 0x57, 0xf4, 0x02, 0x72, 0xf3, 0x11, 0x40, 0x46, 0x8a, 0x83, 0x6b, 0x93, 0x57,
+	0xba, 0xff, 0x5a, 0x8c, 0x9c, 0xd8, 0x83, 0x1f, 0xff, 0xf8, 0xfb, 0x17, 0xb5, 0x6c, 0xdc, 0xb5,
+	0x52, 0x5e, 0x75, 0x09, 0xfe, 0x4c, 0xa9, 0xa1, 0x33, 0x78, 0x43, 0x9c, 0x27, 0xda, 0x4f, 0x61,
+	0x4d, 0x4e, 0x43, 0xa9, 0xbc, 0x19, 0x20, 0x6b, 0x56, 0x44, 0xcd, 0x7d, 0xf4, 0x9e, 0x95, 0xf6,
+	0xa4, 0x33, 0xeb, 0x45, 0x34, 0x41, 0xaf, 0xd0, 0x0f, 0x90, 0x4f, 0x5c, 0x55, 0x54, 0x79, 0xdd,
+	0x0d, 0x5f, 0x96, 0x3f, 0xb8, 0x0e, 0x26, 0x45, 0xdc, 0x13, 0x22, 0xee, 0x1a, 0x77, 0xd2, 0x45,
+	0x44, 0x3d, 0xbf, 0x84, 0x7c, 0xe2, 0x91, 0x4d, 0x15, 0x70, 0xf5, 0x93, 0x91, 0x2a, 0x20, 0xe5,
+	0xad, 0x36, 0x74, 0x21, 0x40, 0x43, 0x1b, 0x04, 0xd8, 0xcd, 0xdf, 0x2f, 0x75, 0xe5, 0xe2, 0x52,
+	0x57, 0xfe, 0xba, 0xd4, 0x95, 0x9f, 0x67, 0xfa, 0xd6, 0x6f, 0x33, 0x5d, 0xb9, 0x98, 0xe9, 0x5b,
+	0x7f, 0xce, 0xf4, 0xad, 0x6f, 0x2b, 0xae, 0xc7, 0x4f, 0x26, 0x7d, 0x73, 0x40, 0x47, 0xf3, 0xfc,
+	0xf8, 0xe7, 0x43, 0x36, 0xfc, 0xde, 0xe2, 0xd3, 0x31, 0x89, 0x08, 0xfb, 0xdb, 0xe2, 0xeb, 0xf6,
+	0xd1, 0xbf, 0x01, 0x00, 0x00, 0xff, 0xff, 0xe4, 0x86, 0xcd, 0x5c, 0xb4, 0x07, 0x00, 0x00,
 }

 // Reference imports to suppress errors if they are not otherwise used.
@ -1022,6 +1033,13 @@ func (m *SimulateRequest) MarshalToSizedBuffer(dAtA []byte) (int, error) {
 	_ = i
 	var l int
 	_ = l
+	if len(m.TxBytes) > 0 {
+		i -= len(m.TxBytes)
+		copy(dAtA[i:], m.TxBytes)
+		i = encodeVarintService(dAtA, i, uint64(len(m.TxBytes)))
+		i--
+		dAtA[i] = 0x12
+	}
 	if m.Tx != nil {
 		{
 			size, err := m.Tx.MarshalToSizedBuffer(dAtA[:i])
@ -1258,6 +1276,10 @@ func (m *SimulateRequest) Size() (n int) {
 		l = m.Tx.Size()
 		n += 1 + l + sovService(uint64(l))
 	}
+	l = len(m.TxBytes)
+	if l > 0 {
+		n += 1 + l + sovService(uint64(l))
+	}
 	return n
 }

@ -1859,6 +1881,40 @@ func (m *SimulateRequest) Unmarshal(dAtA []byte) error {
 				return err
 			}
 			iNdEx = postIndex
+		case 2:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field TxBytes", wireType)
+			}
+			var byteLen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowService
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				byteLen |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if byteLen < 0 {
+				return ErrInvalidLengthService
+			}
+			postIndex := iNdEx + byteLen
+			if postIndex < 0 {
+				return ErrInvalidLengthService
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.TxBytes = append(m.TxBytes[:0], dAtA[iNdEx:postIndex]...)
+			if m.TxBytes == nil {
+				m.TxBytes = []byte{}
+			}
+			iNdEx = postIndex
 		default:
 			iNdEx = preIndex
 			skippy, err := skipService(dAtA[iNdEx:])
--- a/x/auth/client/tx.go
+++ b/x/auth/client/tx.go
@ -19,15 +19,6 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/auth/legacy/legacytx"
 )

-// Codec defines the x/auth account codec to be used for use with the
-// AccountRetriever. The application must be sure to set this to their respective
-// codec that implements the Codec interface and must be the same codec that
-// passed to the x/auth module.
-//
-// TODO:/XXX: Using a package-level global isn't ideal and we should consider
-// refactoring the module manager to allow passing in the correct module codec.
-var Codec codec.Marshaler
-
 // GasEstimateResponse defines a response definition for tx gas estimation.
 type GasEstimateResponse struct {
 	GasEstimate uint64 `json:"gas_estimate" yaml:"gas_estimate"`
--- a/x/auth/tx/builder.go
+++ b/x/auth/tx/builder.go
@ -35,7 +35,6 @@ var (
 	_ client.TxBuilder           = &wrapper{}
 	_ ante.HasExtensionOptionsTx = &wrapper{}
 	_ ExtensionOptionsTxBuilder  = &wrapper{}
-	_ ProtoTxProvider            = &wrapper{}
 )

 // ExtensionOptionsTxBuilder defines a TxBuilder that can also set extensions.
@ -356,8 +355,3 @@ func (w *wrapper) SetNonCriticalExtensionOptions(extOpts ...*codectypes.Any) {
 	w.tx.Body.NonCriticalExtensionOptions = extOpts
 	w.bodyBz = nil
 }
-
-// ProtoTxProvider is a type which can provide a proto transaction.
-type ProtoTxProvider interface {
-	GetProtoTx() *tx.Tx
-}
--- a/x/auth/tx/service.go
+++ b/x/auth/tx/service.go
@ -6,6 +6,7 @@ import (
 	"strings"

 	gogogrpc "github.com/gogo/protobuf/grpc"
+	"github.com/golang/protobuf/proto" //nolint:staticcheck
 	"github.com/grpc-ecosystem/grpc-gateway/runtime"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
@ -92,17 +93,25 @@ func (s txServer) GetTxsEvent(ctx context.Context, req *txtypes.GetTxsEventReque

 // Simulate implements the ServiceServer.Simulate RPC method.
 func (s txServer) Simulate(ctx context.Context, req *txtypes.SimulateRequest) (*txtypes.SimulateResponse, error) {
-	if req == nil || req.Tx == nil {
+	if req == nil {
 		return nil, status.Error(codes.InvalidArgument, "invalid empty tx")
 	}

-	err := req.Tx.UnpackInterfaces(s.interfaceRegistry)
-	if err != nil {
-		return nil, err
+	txBytes := req.TxBytes
+	if txBytes == nil && req.Tx != nil {
+		// This block is for backwards-compatibility.
+		// We used to support passing a `Tx` in req. But if we do that, sig
+		// verification might not pass, because the .Marshal() below might not
+		// be the same marshaling done by the client.
+		var err error
+		txBytes, err = proto.Marshal(req.Tx)
+		if err != nil {
+			return nil, status.Errorf(codes.InvalidArgument, "invalid tx; %v", err)
+		}
 	}
-	txBytes, err := req.Tx.Marshal()
-	if err != nil {
-		return nil, err
+
+	if txBytes == nil {
+		return nil, status.Errorf(codes.InvalidArgument, "empty txBytes is not allowed")
 	}

 	gasInfo, result, err := s.simulate(txBytes)
--- a/x/auth/tx/service_test.go
+++ b/x/auth/tx/service_test.go
@ -7,14 +7,13 @@ import (
 	"fmt"
 	"testing"

-	"github.com/cosmos/cosmos-sdk/testutil/testdata"
-
 	"github.com/stretchr/testify/suite"

 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/flags"
 	clienttx "github.com/cosmos/cosmos-sdk/client/tx"
 	"github.com/cosmos/cosmos-sdk/testutil/network"
+	"github.com/cosmos/cosmos-sdk/testutil/testdata"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/cosmos/cosmos-sdk/types/query"
@ -22,7 +21,6 @@ import (
 	"github.com/cosmos/cosmos-sdk/types/tx"
 	"github.com/cosmos/cosmos-sdk/types/tx/signing"
 	authclient "github.com/cosmos/cosmos-sdk/x/auth/client"
-	authtx "github.com/cosmos/cosmos-sdk/x/auth/tx"
 	bankcli "github.com/cosmos/cosmos-sdk/x/bank/client/testutil"
 	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
 )
@ -81,10 +79,14 @@ func (s *IntegrationTestSuite) TearDownSuite() {
 }

 func (s IntegrationTestSuite) TestSimulateTx_GRPC() {
+	val := s.network.Validators[0]
 	txBuilder := s.mkTxBuilder()
 	// Convert the txBuilder to a tx.Tx.
 	protoTx, err := txBuilderToProtoTx(txBuilder)
 	s.Require().NoError(err)
+	// Encode the txBuilder to txBytes.
+	txBytes, err := val.ClientCtx.TxConfig.TxEncoder()(txBuilder.GetTx())
+	s.Require().NoError(err)

 	testCases := []struct {
 		name      string
@ -93,8 +95,9 @@ func (s IntegrationTestSuite) TestSimulateTx_GRPC() {
 		expErrMsg string
 	}{
 		{"nil request", nil, true, "request cannot be nil"},
-		{"empty request", &tx.SimulateRequest{}, true, "invalid empty tx"},
-		{"valid request", &tx.SimulateRequest{Tx: protoTx}, false, ""},
+		{"empty request", &tx.SimulateRequest{}, true, "empty txBytes is not allowed"},
+		{"valid request with proto tx (deprecated)", &tx.SimulateRequest{Tx: protoTx}, false, ""},
+		{"valid request with tx_bytes", &tx.SimulateRequest{TxBytes: txBytes}, false, ""},
 	}

 	for _, tc := range testCases {
@ -122,6 +125,9 @@ func (s IntegrationTestSuite) TestSimulateTx_GRPCGateway() {
 	// Convert the txBuilder to a tx.Tx.
 	protoTx, err := txBuilderToProtoTx(txBuilder)
 	s.Require().NoError(err)
+	// Encode the txBuilder to txBytes.
+	txBytes, err := val.ClientCtx.TxConfig.TxEncoder()(txBuilder.GetTx())
+	s.Require().NoError(err)

 	testCases := []struct {
 		name      string
@ -129,8 +135,9 @@ func (s IntegrationTestSuite) TestSimulateTx_GRPCGateway() {
 		expErr    bool
 		expErrMsg string
 	}{
-		{"empty request", &tx.SimulateRequest{}, true, "invalid empty tx"},
-		{"valid request", &tx.SimulateRequest{Tx: protoTx}, false, ""},
+		{"empty request", &tx.SimulateRequest{}, true, "empty txBytes is not allowed"},
+		{"valid request with proto tx (deprecated)", &tx.SimulateRequest{Tx: protoTx}, false, ""},
+		{"valid request with tx_bytes", &tx.SimulateRequest{TxBytes: txBytes}, false, ""},
 	}

 	for _, tc := range testCases {
@ -495,9 +502,19 @@ func (s IntegrationTestSuite) mkTxBuilder() client.TxBuilder {
 	return txBuilder
 }

+// protoTxProvider is a type which can provide a proto transaction. It is a
+// workaround to get access to the wrapper TxBuilder's method GetProtoTx().
+// Deprecated: It's only used for testing the deprecated Simulate gRPC endpoint
+// using a proto Tx field.
+type protoTxProvider interface {
+	GetProtoTx() *tx.Tx
+}
+
 // txBuilderToProtoTx converts a txBuilder into a proto tx.Tx.
+// Deprecated: It's only used for testing the deprecated Simulate gRPC endpoint
+// using a proto Tx field.
 func txBuilderToProtoTx(txBuilder client.TxBuilder) (*tx.Tx, error) { // nolint
-	protoProvider, ok := txBuilder.(authtx.ProtoTxProvider)
+	protoProvider, ok := txBuilder.(protoTxProvider)
 	if !ok {
 		return nil, sdkerrors.Wrapf(sdkerrors.ErrInvalidType, "expected proto tx builder, got %T", txBuilder)
 	}
--- a/x/bank/client/rest/tx_test.go
+++ b/x/bank/client/rest/tx_test.go
@ -5,12 +5,10 @@ package rest_test
 import (
 	"fmt"

-	"github.com/cosmos/cosmos-sdk/simapp"
 	"github.com/cosmos/cosmos-sdk/testutil/network"
 	"github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/cosmos/cosmos-sdk/types/rest"
-	authclient "github.com/cosmos/cosmos-sdk/x/auth/client"
 	"github.com/cosmos/cosmos-sdk/x/auth/legacy/legacytx"
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 	bankrest "github.com/cosmos/cosmos-sdk/x/bank/client/rest"
@ -18,9 +16,6 @@ import (
 )

 func (s *IntegrationTestSuite) TestCoinSend() {
-	encodingConfig := simapp.MakeTestEncodingConfig()
-	authclient.Codec = encodingConfig.Marshaler
-
 	val := s.network.Validators[0]

 	account, err := getAccountInfo(val)
--- a/x/staking/types/staking.pb.go
+++ b/x/staking/types/staking.pb.go