Enable/disable coin transfers by denom (#6527)

* initial implementation of per denom sendenabled

* Fix for accidentally removed keyword

* Validate individual param in param array

* Lint fix

* Refactor bank params to use protobuf
Modified SendEnabled property to be part of generic Params object
Updated genesis functions to use default params structure

* Refactor simulation genesis for clarity

* update changelog for bank sendenable per denom

* fix NoOpMsg type in multisend test

* Add a coin denom send check utility function

* Additional godoc comments and clarification

* Add default send enabled parameter to bank.
Remove empty denom capability from SendEnabled parameters
Update simulation to exercise both configuration options independently

* Minor suggested improvements.

* simulation fix

* bank proto sendenabled package name removed

* Remove extra gogo proto yaml tags

* Params rename IsSendEnabled to SendEnabledDenom

* Refactor to SendEnabledCoin(s)

* update slashing test to use bank params

* Clean up change log entry for feature.

Co-authored-by: Federico Kunze <31522760+fedekunze@users.noreply.github.com>
Co-authored-by: Alessio Treglia <alessio@tendermint.com>
Co-authored-by: Alexander Bezobchuk <alexanderbez@users.noreply.github.com>

CHANGELOG.md

@@ -203,6 +203,9 @@ invalid or incomplete requests.
 ### State Machine Breaking
 
 * (x/bank) [\#6283](https://github.com/cosmos/cosmos-sdk/pull/6283) Create account if recipient does not exist on handing `MsgMultiSend`.
+* (x/bank) [\#6518](https://github.com/cosmos/cosmos-sdk/pull/6518) Support for global and per-denomination send enabled flags.
+  * Existing send_enabled global flag has been moved into a Params structure as `default_send_enabled`.
+  * An array of: `{denom: string, enabled: bool}` is added to bank Params to support per-denomination override of global default value.
 * (x/staking) [\#6061](https://github.com/cosmos/cosmos-sdk/pull/6061) Allow a validator to immediately unjail when no signing info is present due to
 falling below their minimum self-delegation and never having been bonded. The validator may immediately unjail once they've met their minimum self-delegation.
 * (x/supply) [\#6010](https://github.com/cosmos/cosmos-sdk/pull/6010) Removed the `x/supply` module by merging the existing types and APIs into the `x/bank` module.

proto/cosmos/bank/bank.proto

@@ -7,6 +7,25 @@ import "cosmos/cosmos.proto";
 
 option go_package = "github.com/cosmos/cosmos-sdk/x/bank/types";
 
+// Params defines the set of bank parameters.
+message Params {
+  option (gogoproto.goproto_stringer) = false;
+  repeated SendEnabled send_enabled = 1[
+    (gogoproto.moretags) = "yaml:\"send_enabled,omitempty\""
+  ];
+  bool default_send_enabled = 2[
+    (gogoproto.moretags) = "yaml:\"default_send_enabled,omitempty\""
+  ];
+}
+
+// Send enabled configuration properties for each denomination
+message SendEnabled {
+  option (gogoproto.equal) = true;
+  option (gogoproto.goproto_stringer) = false;
+  string denom = 1;
+  bool enabled = 2;
+}
+
 // MsgSend - high level transaction of the coin module
 message MsgSend {
   option (gogoproto.equal) = true;

simapp/test_helpers.go

@@ -118,7 +118,7 @@ func SetupWithGenesisValSet(t *testing.T, valSet *tmtypes.ValidatorSet, genAccs
 	}
 
 	// update total supply
-	bankGenesis := banktypes.NewGenesisState(banktypes.DefaultGenesisState().SendEnabled, balances, totalSupply)
+	bankGenesis := banktypes.NewGenesisState(banktypes.DefaultGenesisState().Params, balances, totalSupply)
 	genesisState[banktypes.ModuleName] = app.Codec().MustMarshalJSON(bankGenesis)
 
 	stateBytes, err := codec.MarshalJSONIndent(app.Codec(), genesisState)
@@ -157,7 +157,7 @@ func SetupWithGenesisAccounts(genAccs []authtypes.GenesisAccount, balances ...ba
 		totalSupply = totalSupply.Add(b.Coins...)
 	}
 
-	bankGenesis := banktypes.NewGenesisState(banktypes.DefaultGenesisState().SendEnabled, balances, totalSupply)
+	bankGenesis := banktypes.NewGenesisState(banktypes.DefaultGenesisState().Params, balances, totalSupply)
 	genesisState[banktypes.ModuleName] = app.Codec().MustMarshalJSON(bankGenesis)
 
 	stateBytes, err := codec.MarshalJSONIndent(app.Codec(), genesisState)

x/bank/genesis.go

@@ -10,7 +10,7 @@ import (
 
 // InitGenesis initializes the bank module's state from a given genesis state.
 func InitGenesis(ctx sdk.Context, keeper keeper.Keeper, genState types.GenesisState) {
-	keeper.SetSendEnabled(ctx, genState.SendEnabled)
+	keeper.SetParams(ctx, genState.Params)
 
 	var totalSupply sdk.Coins
 
@@ -57,11 +57,14 @@ func ExportGenesis(ctx sdk.Context, keeper keeper.Keeper) types.GenesisState {
 		})
 	}
 
-	return types.NewGenesisState(keeper.GetSendEnabled(ctx), balances, keeper.GetSupply(ctx).GetTotal())
+	return types.NewGenesisState(keeper.GetParams(ctx), balances, keeper.GetSupply(ctx).GetTotal())
 }
 
 // ValidateGenesis performs basic validation of supply genesis data returning an
 // error for any failed validation criteria.
 func ValidateGenesis(data types.GenesisState) error {
+	if err := data.Params.Validate(); err != nil {
+		return err
+	}
 	return types.NewSupply(data.Supply).ValidateBasic()
 }

x/bank/handler.go

@@ -30,8 +30,8 @@ func NewHandler(k keeper.Keeper) sdk.Handler {
 
 // Handle MsgSend.
 func handleMsgSend(ctx sdk.Context, k keeper.Keeper, msg *types.MsgSend) (*sdk.Result, error) {
-	if !k.GetSendEnabled(ctx) {
+	if err := k.SendEnabledCoins(ctx, msg.Amount...); err != nil {
-		return nil, types.ErrSendDisabled
+		return nil, err
 	}
 
 	if k.BlockedAddr(msg.ToAddress) {
@@ -66,8 +66,10 @@ func handleMsgSend(ctx sdk.Context, k keeper.Keeper, msg *types.MsgSend) (*sdk.R
 // Handle MsgMultiSend.
 func handleMsgMultiSend(ctx sdk.Context, k keeper.Keeper, msg *types.MsgMultiSend) (*sdk.Result, error) {
 	// NOTE: totalIn == totalOut should already have been checked
-	if !k.GetSendEnabled(ctx) {
+	for _, in := range msg.Inputs {
-		return nil, types.ErrSendDisabled
+		if err := k.SendEnabledCoins(ctx, in.Coins...); err != nil {
+			return nil, err
+		}
 	}
 
 	for _, out := range msg.Outputs {

x/bank/keeper/keeper_test.go

@@ -69,7 +69,7 @@ func (suite *IntegrationTestSuite) SetupTest() {
 	ctx := app.BaseApp.NewContext(false, abci.Header{})
 
 	app.AccountKeeper.SetParams(ctx, authtypes.DefaultParams())
-	app.BankKeeper.SetSendEnabled(ctx, true)
+	app.BankKeeper.SetParams(ctx, types.DefaultParams())
 
 	suite.app = app
 	suite.ctx = ctx
@@ -454,9 +454,45 @@ func (suite *IntegrationTestSuite) TestBalance() {
 
 func (suite *IntegrationTestSuite) TestSendEnabled() {
 	app, ctx := suite.app, suite.ctx
-	enabled := false
+	enabled := true
-	app.BankKeeper.SetSendEnabled(ctx, enabled)
+	params := types.DefaultParams()
-	suite.Require().Equal(enabled, app.BankKeeper.GetSendEnabled(ctx))
+	suite.Require().Equal(enabled, params.DefaultSendEnabled)
+
+	app.BankKeeper.SetParams(ctx, params)
+
+	bondCoin := sdk.NewCoin(sdk.DefaultBondDenom, sdk.OneInt())
+	fooCoin := sdk.NewCoin("foocoin", sdk.OneInt())
+	barCoin := sdk.NewCoin("barcoin", sdk.OneInt())
+
+	// assert with default (all denom) send enabled both Bar and Bond Denom are enabled
+	suite.Require().Equal(enabled, app.BankKeeper.SendEnabledCoin(ctx, barCoin))
+	suite.Require().Equal(enabled, app.BankKeeper.SendEnabledCoin(ctx, bondCoin))
+
+	// Both coins should be send enabled.
+	err := app.BankKeeper.SendEnabledCoins(ctx, fooCoin, bondCoin)
+	suite.Require().NoError(err)
+
+	// Set default send_enabled to !enabled, add a foodenom that overrides default as enabled
+	params.DefaultSendEnabled = !enabled
+	params = params.SetSendEnabledParam(fooCoin.Denom, enabled)
+	app.BankKeeper.SetParams(ctx, params)
+
+	// Expect our specific override to be enabled, others to be !enabled.
+	suite.Require().Equal(enabled, app.BankKeeper.SendEnabledCoin(ctx, fooCoin))
+	suite.Require().Equal(!enabled, app.BankKeeper.SendEnabledCoin(ctx, barCoin))
+	suite.Require().Equal(!enabled, app.BankKeeper.SendEnabledCoin(ctx, bondCoin))
+
+	// Foo coin should be send enabled.
+	err = app.BankKeeper.SendEnabledCoins(ctx, fooCoin)
+	suite.Require().NoError(err)
+
+	// Expect an error when one coin is not send enabled.
+	err = app.BankKeeper.SendEnabledCoins(ctx, fooCoin, bondCoin)
+	suite.Require().Error(err)
+
+	// Expect an error when all coins are not send enabled.
+	err = app.BankKeeper.SendEnabledCoins(ctx, bondCoin, barCoin)
+	suite.Require().Error(err)
 }
 
 func (suite *IntegrationTestSuite) TestHasBalance() {
@@ -531,7 +567,7 @@ func (suite *IntegrationTestSuite) TestMsgSendEvents() {
 func (suite *IntegrationTestSuite) TestMsgMultiSendEvents() {
 	app, ctx := suite.app, suite.ctx
 
-	app.BankKeeper.SetSendEnabled(ctx, true)
+	app.BankKeeper.SetParams(ctx, types.DefaultParams())
 
 	addr := sdk.AccAddress([]byte("addr1"))
 	addr2 := sdk.AccAddress([]byte("addr2"))

x/bank/keeper/send.go

@@ -24,8 +24,11 @@ type SendKeeper interface {
 	SetBalance(ctx sdk.Context, addr sdk.AccAddress, balance sdk.Coin) error
 	SetBalances(ctx sdk.Context, addr sdk.AccAddress, balances sdk.Coins) error
 
-	GetSendEnabled(ctx sdk.Context) bool
+	GetParams(ctx sdk.Context) types.Params
-	SetSendEnabled(ctx sdk.Context, enabled bool)
+	SetParams(ctx sdk.Context, params types.Params)
+
+	SendEnabledCoin(ctx sdk.Context, coin sdk.Coin) bool
+	SendEnabledCoins(ctx sdk.Context, coins ...sdk.Coin) error
 
 	BlockedAddr(addr sdk.AccAddress) bool
 }
@@ -60,6 +63,17 @@ func NewBaseSendKeeper(
 	}
 }
 
+// GetParams returns the total set of bank parameters.
+func (k BaseSendKeeper) GetParams(ctx sdk.Context) (params types.Params) {
+	k.paramSpace.GetParamSet(ctx, &params)
+	return params
+}
+
+// SetParams sets the total set of bank parameters.
+func (k BaseSendKeeper) SetParams(ctx sdk.Context, params types.Params) {
+	k.paramSpace.SetParamSet(ctx, &params)
+}
+
 // InputOutputCoins performs multi-send functionality. It accepts a series of
 // inputs that correspond to a series of outputs. It returns an error if the
 // inputs and outputs don't lineup or if any single transfer of tokens fails.
@@ -256,16 +270,21 @@ func (k BaseSendKeeper) SetBalance(ctx sdk.Context, addr sdk.AccAddress, balance
 	return nil
 }
 
-// GetSendEnabled returns the current SendEnabled
+// SendEnabledCoins checks the coins provide and returns an ErrSendDisabled if
-func (k BaseSendKeeper) GetSendEnabled(ctx sdk.Context) bool {
+// any of the coins are not configured for sending.  Returns nil if sending is enabled
-	var enabled bool
+// for all provided coin
-	k.paramSpace.Get(ctx, types.ParamStoreKeySendEnabled, &enabled)
+func (k BaseSendKeeper) SendEnabledCoins(ctx sdk.Context, coins ...sdk.Coin) error {
-	return enabled
+	for _, coin := range coins {
+		if !k.SendEnabledCoin(ctx, coin) {
+			return sdkerrors.Wrapf(types.ErrSendDisabled, "%s transfers are currently disabled", coin.Denom)
+		}
+	}
+	return nil
 }
 
-// SetSendEnabled sets the send enabled
+// SendEnabledCoin returns the current SendEnabled status of the provided coin's denom
-func (k BaseSendKeeper) SetSendEnabled(ctx sdk.Context, enabled bool) {
+func (k BaseSendKeeper) SendEnabledCoin(ctx sdk.Context, coin sdk.Coin) bool {
-	k.paramSpace.Set(ctx, types.ParamStoreKeySendEnabled, &enabled)
+	return k.GetParams(ctx).SendEnabledDenom(coin.Denom)
 }
 
 // BlockedAddr checks if a given address is restricted from

x/bank/simulation/genesis.go

@@ -3,21 +3,36 @@ package simulation
 // DONTCOVER
 
 import (
+	"fmt"
 	"math/rand"
 
+	"github.com/cosmos/cosmos-sdk/codec"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/types/module"
 	"github.com/cosmos/cosmos-sdk/x/bank/types"
 )
 
-// Simulation parameter constants
+// RandomGenesisDefaultSendParam computes randomized allow all send transfers param for the bank module
-const (
+func RandomGenesisDefaultSendParam(r *rand.Rand) bool {
-	SendEnabled = "send_enabled"
+	// 90% chance of transfers being enable or P(a) = 0.9 for success
-)
+	return r.Int63n(101) <= 90
+}
 
-// GenSendEnabled randomized SendEnabled
+// RandomGenesisSendParams randomized Parameters for the bank module
-func GenSendEnabled(r *rand.Rand) bool {
+func RandomGenesisSendParams(r *rand.Rand) types.SendEnabledParams {
-	return r.Int63n(101) <= 95 // 95% chance of transfers being enabled
+	params := types.DefaultParams()
+	// 90% chance of transfers being DefaultSendEnabled=true or P(a) = 0.9 for success
+	// 50% of the time add an additional denom specific record (P(b) = 0.475 = 0.5 * 0.95)
+	if r.Int63n(101) <= 50 {
+		// set send enabled 95% of the time
+		bondEnabled := r.Int63n(101) <= 95
+		params = params.SetSendEnabledParam(
+			sdk.DefaultBondDenom,
+			bondEnabled)
+	}
+
+	// overall probability of enabled for bond denom is 94.75% (P(a)+P(b) - P(a)*P(b))
+	return params.SendEnabled
 }
 
 // RandomGenesisAccounts returns a slice of account balances. Each account has
@@ -37,16 +52,31 @@ func RandomGenesisBalances(simState *module.SimulationState) []types.Balance {
 
 // RandomizedGenState generates a random GenesisState for bank
 func RandomizedGenState(simState *module.SimulationState) {
-	var sendEnabled bool
+	var sendEnabledParams types.SendEnabledParams
 	simState.AppParams.GetOrGenerate(
-		simState.Cdc, SendEnabled, &sendEnabled, simState.Rand,
+		simState.Cdc, string(types.KeySendEnabled), &sendEnabledParams, simState.Rand,
-		func(r *rand.Rand) { sendEnabled = GenSendEnabled(r) },
+		func(r *rand.Rand) { sendEnabledParams = RandomGenesisSendParams(r) },
+	)
+
+	var defaultSendEnabledParam bool
+	simState.AppParams.GetOrGenerate(
+		simState.Cdc, string(types.KeyDefaultSendEnabled), &defaultSendEnabledParam, simState.Rand,
+		func(r *rand.Rand) { defaultSendEnabledParam = RandomGenesisDefaultSendParam(r) },
 	)
 
 	numAccs := int64(len(simState.Accounts))
 	totalSupply := sdk.NewInt(simState.InitialStake * (numAccs + simState.NumBonded))
 	supply := sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, totalSupply))
 
-	bankGenesis := types.NewGenesisState(sendEnabled, RandomGenesisBalances(simState), supply)
+	bankGenesis := types.GenesisState{
+		Params: types.Params{
+			SendEnabled:        sendEnabledParams,
+			DefaultSendEnabled: defaultSendEnabledParam,
+		},
+		Balances: RandomGenesisBalances(simState),
+		Supply:   supply,
+	}
+
+	fmt.Printf("Selected randomly generated bank parameters:\n%s\n", codec.MustMarshalJSONIndent(simState.Cdc, bankGenesis.Params))
 	simState.GenState[types.ModuleName] = simState.Cdc.MustMarshalJSON(bankGenesis)
 }

x/bank/simulation/operations.go

@@ -59,13 +59,13 @@ func SimulateMsgSend(ak types.AccountKeeper, bk keeper.Keeper) simtypes.Operatio
 		r *rand.Rand, app *baseapp.BaseApp, ctx sdk.Context,
 		accs []simtypes.Account, chainID string,
 	) (simtypes.OperationMsg, []simtypes.FutureOperation, error) {
-
-		if !bk.GetSendEnabled(ctx) {
-			return simtypes.NoOpMsg(types.ModuleName, types.TypeMsgSend, "transfers are not enabled"), nil, nil
-		}
-
 		simAccount, toSimAcc, coins, skip := randomSendFields(r, ctx, accs, bk, ak)
 
+		// Check send_enabled status of each coin denom
+		if err := bk.SendEnabledCoins(ctx, coins...); err != nil {
+			return simtypes.NoOpMsg(types.ModuleName, types.TypeMsgSend, err.Error()), nil, nil
+		}
+
 		if skip {
 			return simtypes.NoOpMsg(types.ModuleName, types.TypeMsgSend, "skip all transfers"), nil, nil
 		}
@@ -130,10 +130,6 @@ func SimulateMsgMultiSend(ak types.AccountKeeper, bk keeper.Keeper) simtypes.Ope
 		accs []simtypes.Account, chainID string,
 	) (simtypes.OperationMsg, []simtypes.FutureOperation, error) {
 
-		if !bk.GetSendEnabled(ctx) {
-			return simtypes.NoOpMsg(types.ModuleName, types.TypeMsgMultiSend, "transfers are not enabled"), nil, nil
-		}
-
 		// random number of inputs/outputs between [1, 3]
 		inputs := make([]types.Input, r.Intn(3)+1)
 		outputs := make([]types.Output, r.Intn(3)+1)
@@ -169,6 +165,11 @@ func SimulateMsgMultiSend(ak types.AccountKeeper, bk keeper.Keeper) simtypes.Ope
 			totalSentCoins = totalSentCoins.Add(coins...)
 		}
 
+		// Check send_enabled status of each sent coin denom
+		if err := bk.SendEnabledCoins(ctx, totalSentCoins...); err != nil {
+			return simtypes.NoOpMsg(types.ModuleName, types.TypeMsgMultiSend, err.Error()), nil, nil
+		}
+
 		for o := range outputs {
 			outAddr, _ := simtypes.RandomAcc(r, accs)
 

x/bank/simulation/params.go

@@ -12,15 +12,18 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/bank/types"
 )
 
-const keySendEnabled = "sendenabled"
-
 // ParamChanges defines the parameters that can be modified by param change proposals
 // on the simulation
 func ParamChanges(r *rand.Rand) []simtypes.ParamChange {
 	return []simtypes.ParamChange{
-		simulation.NewSimParamChange(types.ModuleName, keySendEnabled,
+		simulation.NewSimParamChange(types.ModuleName, string(types.KeySendEnabled),
 			func(r *rand.Rand) string {
-				return fmt.Sprintf("%v", GenSendEnabled(r))
+				return fmt.Sprintf("%s", types.ModuleCdc.MustMarshalJSON(RandomGenesisSendParams(r)))
+			},
+		),
+		simulation.NewSimParamChange(types.ModuleName, string(types.KeyDefaultSendEnabled),
+			func(r *rand.Rand) string {
+				return fmt.Sprintf("%v", RandomGenesisDefaultSendParam(r))
 			},
 		),
 	}

x/bank/spec/05_params.md

@@ -6,7 +6,20 @@ order: 5
 
 The bank module contains the following parameters:
 
-| Key         | Type | Example |
+| Key                | Type          | Example                            |
-|-------------|------|---------|
+|--------------------|---------------|------------------------------------|
-| sendenabled | bool | true    |
+| SendEnabled        | []SendEnabled | [{denom: "stake", enabled: true }] |
+| DefaultSendEnabled | bool          | true                               |
 
+
+## SendEnabled
+
+The send enabled parameter is an array of SendEnabled entries mapping coin
+denominations to their send_enabled status.  Entries in this list take
+precedence over the `DefaultSendEnabled` setting.
+
+## DefaultSendEnabled
+
+The default send enabled value controls send transfer capability for all
+coin denominations unless specifically included in the array of `SendEnabled`
+parameters.

x/bank/types/bank.pb.go

@@ -27,6 +27,110 @@ var _ = math.Inf
 // proto package needs to be updated.
 const _ = proto.GoGoProtoPackageIsVersion3 // please upgrade the proto package
 
+// Params defines the set of bank parameters.
+type Params struct {
+	SendEnabled        []*SendEnabled `protobuf:"bytes,1,rep,name=send_enabled,json=sendEnabled,proto3" json:"send_enabled,omitempty" yaml:"send_enabled,omitempty"`
+	DefaultSendEnabled bool           `protobuf:"varint,2,opt,name=default_send_enabled,json=defaultSendEnabled,proto3" json:"default_send_enabled,omitempty" yaml:"default_send_enabled,omitempty"`
+}
+
+func (m *Params) Reset()      { *m = Params{} }
+func (*Params) ProtoMessage() {}
+func (*Params) Descriptor() ([]byte, []int) {
+	return fileDescriptor_717c78e54d4b5794, []int{0}
+}
+func (m *Params) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *Params) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_Params.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalToSizedBuffer(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *Params) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Params.Merge(m, src)
+}
+func (m *Params) XXX_Size() int {
+	return m.Size()
+}
+func (m *Params) XXX_DiscardUnknown() {
+	xxx_messageInfo_Params.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Params proto.InternalMessageInfo
+
+func (m *Params) GetSendEnabled() []*SendEnabled {
+	if m != nil {
+		return m.SendEnabled
+	}
+	return nil
+}
+
+func (m *Params) GetDefaultSendEnabled() bool {
+	if m != nil {
+		return m.DefaultSendEnabled
+	}
+	return false
+}
+
+// Send enabled configuration properties for each denomination
+type SendEnabled struct {
+	Denom   string `protobuf:"bytes,1,opt,name=denom,proto3" json:"denom,omitempty"`
+	Enabled bool   `protobuf:"varint,2,opt,name=enabled,proto3" json:"enabled,omitempty"`
+}
+
+func (m *SendEnabled) Reset()      { *m = SendEnabled{} }
+func (*SendEnabled) ProtoMessage() {}
+func (*SendEnabled) Descriptor() ([]byte, []int) {
+	return fileDescriptor_717c78e54d4b5794, []int{1}
+}
+func (m *SendEnabled) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *SendEnabled) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_SendEnabled.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalToSizedBuffer(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *SendEnabled) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_SendEnabled.Merge(m, src)
+}
+func (m *SendEnabled) XXX_Size() int {
+	return m.Size()
+}
+func (m *SendEnabled) XXX_DiscardUnknown() {
+	xxx_messageInfo_SendEnabled.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_SendEnabled proto.InternalMessageInfo
+
+func (m *SendEnabled) GetDenom() string {
+	if m != nil {
+		return m.Denom
+	}
+	return ""
+}
+
+func (m *SendEnabled) GetEnabled() bool {
+	if m != nil {
+		return m.Enabled
+	}
+	return false
+}
+
 // MsgSend - high level transaction of the coin module
 type MsgSend struct {
 	FromAddress github_com_cosmos_cosmos_sdk_types.AccAddress `protobuf:"bytes,1,opt,name=from_address,json=fromAddress,proto3,casttype=github.com/cosmos/cosmos-sdk/types.AccAddress" json:"from_address,omitempty" yaml:"from_address"`
@@ -38,7 +142,7 @@ func (m *MsgSend) Reset()         { *m = MsgSend{} }
 func (m *MsgSend) String() string { return proto.CompactTextString(m) }
 func (*MsgSend) ProtoMessage()    {}
 func (*MsgSend) Descriptor() ([]byte, []int) {
-	return fileDescriptor_717c78e54d4b5794, []int{0}
+	return fileDescriptor_717c78e54d4b5794, []int{2}
 }
 func (m *MsgSend) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -98,7 +202,7 @@ func (m *Input) Reset()         { *m = Input{} }
 func (m *Input) String() string { return proto.CompactTextString(m) }
 func (*Input) ProtoMessage()    {}
 func (*Input) Descriptor() ([]byte, []int) {
-	return fileDescriptor_717c78e54d4b5794, []int{1}
+	return fileDescriptor_717c78e54d4b5794, []int{3}
 }
 func (m *Input) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -151,7 +255,7 @@ func (m *Output) Reset()         { *m = Output{} }
 func (m *Output) String() string { return proto.CompactTextString(m) }
 func (*Output) ProtoMessage()    {}
 func (*Output) Descriptor() ([]byte, []int) {
-	return fileDescriptor_717c78e54d4b5794, []int{2}
+	return fileDescriptor_717c78e54d4b5794, []int{4}
 }
 func (m *Output) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -204,7 +308,7 @@ func (m *MsgMultiSend) Reset()         { *m = MsgMultiSend{} }
 func (m *MsgMultiSend) String() string { return proto.CompactTextString(m) }
 func (*MsgMultiSend) ProtoMessage()    {}
 func (*MsgMultiSend) Descriptor() ([]byte, []int) {
-	return fileDescriptor_717c78e54d4b5794, []int{3}
+	return fileDescriptor_717c78e54d4b5794, []int{5}
 }
 func (m *MsgMultiSend) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -256,7 +360,7 @@ type Supply struct {
 func (m *Supply) Reset()      { *m = Supply{} }
 func (*Supply) ProtoMessage() {}
 func (*Supply) Descriptor() ([]byte, []int) {
-	return fileDescriptor_717c78e54d4b5794, []int{4}
+	return fileDescriptor_717c78e54d4b5794, []int{6}
 }
 func (m *Supply) XXX_Unmarshal(b []byte) error {
 	return m.Unmarshal(b)
@@ -286,6 +390,8 @@ func (m *Supply) XXX_DiscardUnknown() {
 var xxx_messageInfo_Supply proto.InternalMessageInfo
 
 func init() {
+	proto.RegisterType((*Params)(nil), "cosmos.bank.Params")
+	proto.RegisterType((*SendEnabled)(nil), "cosmos.bank.SendEnabled")
 	proto.RegisterType((*MsgSend)(nil), "cosmos.bank.MsgSend")
 	proto.RegisterType((*Input)(nil), "cosmos.bank.Input")
 	proto.RegisterType((*Output)(nil), "cosmos.bank.Output")
@@ -296,38 +402,73 @@ func init() {
 func init() { proto.RegisterFile("cosmos/bank/bank.proto", fileDescriptor_717c78e54d4b5794) }
 
 var fileDescriptor_717c78e54d4b5794 = []byte{
-	// 457 bytes of a gzipped FileDescriptorProto
+	// 583 bytes of a gzipped FileDescriptorProto
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-	0xff, 0xa5, 0xa6, 0xc2, 0x41, 0x82, 0x04, 0x00, 0x00,
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+	0xf0, 0x79, 0xae, 0x83, 0xe7, 0x0b, 0x5d, 0x39, 0x5d, 0xe8, 0xca, 0xc7, 0x85, 0xae, 0x3c, 0xdc,
+	0x3a, 0x8f, 0x1e, 0x0f, 0xd6, 0x57, 0xf9, 0x63, 0xb9, 0xf3, 0x2d, 0x00, 0x00, 0xff, 0xff, 0xba,
+	0x32, 0x90, 0x68, 0x99, 0x05, 0x00, 0x00,
 }
 
+func (this *SendEnabled) Equal(that interface{}) bool {
+	if that == nil {
+		return this == nil
+	}
+
+	that1, ok := that.(*SendEnabled)
+	if !ok {
+		that2, ok := that.(SendEnabled)
+		if ok {
+			that1 = &that2
+		} else {
+			return false
+		}
+	}
+	if that1 == nil {
+		return this == nil
+	} else if this == nil {
+		return false
+	}
+	if this.Denom != that1.Denom {
+		return false
+	}
+	if this.Enabled != that1.Enabled {
+		return false
+	}
+	return true
+}
 func (this *MsgSend) Equal(that interface{}) bool {
 	if that == nil {
 		return this == nil
@@ -493,6 +634,93 @@ func (this *Supply) Equal(that interface{}) bool {
 	}
 	return true
 }
+func (m *Params) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *Params) MarshalTo(dAtA []byte) (int, error) {
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+func (m *Params) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
+	_ = i
+	var l int
+	_ = l
+	if m.DefaultSendEnabled {
+		i--
+		if m.DefaultSendEnabled {
+			dAtA[i] = 1
+		} else {
+			dAtA[i] = 0
+		}
+		i--
+		dAtA[i] = 0x10
+	}
+	if len(m.SendEnabled) > 0 {
+		for iNdEx := len(m.SendEnabled) - 1; iNdEx >= 0; iNdEx-- {
+			{
+				size, err := m.SendEnabled[iNdEx].MarshalToSizedBuffer(dAtA[:i])
+				if err != nil {
+					return 0, err
+				}
+				i -= size
+				i = encodeVarintBank(dAtA, i, uint64(size))
+			}
+			i--
+			dAtA[i] = 0xa
+		}
+	}
+	return len(dAtA) - i, nil
+}
+
+func (m *SendEnabled) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *SendEnabled) MarshalTo(dAtA []byte) (int, error) {
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+func (m *SendEnabled) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
+	_ = i
+	var l int
+	_ = l
+	if m.Enabled {
+		i--
+		if m.Enabled {
+			dAtA[i] = 1
+		} else {
+			dAtA[i] = 0
+		}
+		i--
+		dAtA[i] = 0x10
+	}
+	if len(m.Denom) > 0 {
+		i -= len(m.Denom)
+		copy(dAtA[i:], m.Denom)
+		i = encodeVarintBank(dAtA, i, uint64(len(m.Denom)))
+		i--
+		dAtA[i] = 0xa
+	}
+	return len(dAtA) - i, nil
+}
+
 func (m *MsgSend) Marshal() (dAtA []byte, err error) {
 	size := m.Size()
 	dAtA = make([]byte, size)
@@ -731,6 +959,40 @@ func encodeVarintBank(dAtA []byte, offset int, v uint64) int {
 	dAtA[offset] = uint8(v)
 	return base
 }
+func (m *Params) Size() (n int) {
+	if m == nil {
+		return 0
+	}
+	var l int
+	_ = l
+	if len(m.SendEnabled) > 0 {
+		for _, e := range m.SendEnabled {
+			l = e.Size()
+			n += 1 + l + sovBank(uint64(l))
+		}
+	}
+	if m.DefaultSendEnabled {
+		n += 2
+	}
+	return n
+}
+
+func (m *SendEnabled) Size() (n int) {
+	if m == nil {
+		return 0
+	}
+	var l int
+	_ = l
+	l = len(m.Denom)
+	if l > 0 {
+		n += 1 + l + sovBank(uint64(l))
+	}
+	if m.Enabled {
+		n += 2
+	}
+	return n
+}
+
 func (m *MsgSend) Size() (n int) {
 	if m == nil {
 		return 0
@@ -834,6 +1096,218 @@ func sovBank(x uint64) (n int) {
 func sozBank(x uint64) (n int) {
 	return sovBank(uint64((x << 1) ^ uint64((int64(x) >> 63))))
 }
+func (m *Params) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowBank
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= uint64(b&0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: Params: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: Params: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field SendEnabled", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowBank
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				msglen |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthBank
+			}
+			postIndex := iNdEx + msglen
+			if postIndex < 0 {
+				return ErrInvalidLengthBank
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.SendEnabled = append(m.SendEnabled, &SendEnabled{})
+			if err := m.SendEnabled[len(m.SendEnabled)-1].Unmarshal(dAtA[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field DefaultSendEnabled", wireType)
+			}
+			var v int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowBank
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				v |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			m.DefaultSendEnabled = bool(v != 0)
+		default:
+			iNdEx = preIndex
+			skippy, err := skipBank(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthBank
+			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthBank
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
+func (m *SendEnabled) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowBank
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= uint64(b&0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: SendEnabled: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: SendEnabled: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Denom", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowBank
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthBank
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex < 0 {
+				return ErrInvalidLengthBank
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Denom = string(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Enabled", wireType)
+			}
+			var v int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowBank
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				v |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			m.Enabled = bool(v != 0)
+		default:
+			iNdEx = preIndex
+			skippy, err := skipBank(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthBank
+			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthBank
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
 func (m *MsgSend) Unmarshal(dAtA []byte) error {
 	l := len(dAtA)
 	iNdEx := 0

x/bank/types/genesis.go

@@ -14,9 +14,9 @@ var _ exported.GenesisBalance = (*Balance)(nil)
 
 // GenesisState defines the bank module's genesis state.
 type GenesisState struct {
-	SendEnabled bool      `json:"send_enabled" yaml:"send_enabled"`
+	Params   Params    `json:"params" yaml:"params"`
-	Balances    []Balance `json:"balances" yaml:"balances"`
+	Balances []Balance `json:"balances" yaml:"balances"`
-	Supply      sdk.Coins `json:"supply" yaml:"supply"`
+	Supply   sdk.Coins `json:"supply" yaml:"supply"`
 }
 
 // Balance defines an account address and balance pair used in the bank module's
@@ -50,17 +50,17 @@ func SanitizeGenesisBalances(balances []Balance) []Balance {
 }
 
 // NewGenesisState creates a new genesis state.
-func NewGenesisState(sendEnabled bool, balances []Balance, supply sdk.Coins) GenesisState {
+func NewGenesisState(params Params, balances []Balance, supply sdk.Coins) GenesisState {
 	return GenesisState{
-		SendEnabled: sendEnabled,
+		Params:   params,
-		Balances:    balances,
+		Balances: balances,
-		Supply:      supply,
+		Supply:   supply,
 	}
 }
 
 // DefaultGenesisState returns a default bank module genesis state.
 func DefaultGenesisState() GenesisState {
-	return NewGenesisState(true, []Balance{}, DefaultSupply().GetTotal())
+	return NewGenesisState(DefaultParams(), []Balance{}, DefaultSupply().GetTotal())
 }
 
 // GetGenesisStateFromAppState returns x/bank GenesisState given raw application

x/bank/types/params.go

@@ -3,7 +3,9 @@ package types
 import (
 	"fmt"
 
+	sdk "github.com/cosmos/cosmos-sdk/types"
 	paramtypes "github.com/cosmos/cosmos-sdk/x/params/types"
+	yaml "gopkg.in/yaml.v2"
 )
 
 const (
@@ -11,21 +13,129 @@ const (
 	DefaultSendEnabled = true
 )
 
-// ParamStoreKeySendEnabled is store's key for SendEnabled
+var (
-var ParamStoreKeySendEnabled = []byte("sendenabled")
+	// KeySendEnabled is store's key for SendEnabled Params
+	KeySendEnabled = []byte("SendEnabled")
+	// KeyDefaultSendEnabled is store's key for the DefaultSendEnabled option
+	KeyDefaultSendEnabled = []byte("DefaultSendEnabled")
+)
 
-// ParamKeyTable type declaration for parameters
+// ParamKeyTable for bank module.
 func ParamKeyTable() paramtypes.KeyTable {
-	return paramtypes.NewKeyTable(
+	return paramtypes.NewKeyTable().RegisterParamSet(&Params{})
-		paramtypes.NewParamSetPair(ParamStoreKeySendEnabled, false, validateSendEnabled),
+}
-	)
+
+// NewParams creates a new parameter configuration for the bank module
+func NewParams(defaultSendEnabled bool, sendEnabledParams SendEnabledParams) Params {
+	return Params{
+		SendEnabled:        sendEnabledParams,
+		DefaultSendEnabled: defaultSendEnabled,
+	}
+}
+
+// DefaultParams is the default parameter configuration for the bank module
+func DefaultParams() Params {
+	return Params{
+		SendEnabled: SendEnabledParams{},
+		// The default send enabled value allows send transfers for all coin denoms
+		DefaultSendEnabled: true,
+	}
+}
+
+// Validate all bank module parameters
+func (p Params) Validate() error {
+	if err := validateSendEnabledParams(p.SendEnabled); err != nil {
+		return err
+	}
+	return validateIsBool(p.DefaultSendEnabled)
+}
+
+// String implements the Stringer interface.
+func (p Params) String() string {
+	out, _ := yaml.Marshal(p)
+	return string(out)
+}
+
+// SendEnabledDenom returns true if the given denom is enabled for sending
+func (p Params) SendEnabledDenom(denom string) bool {
+	for _, pse := range p.SendEnabled {
+		if pse.Denom == denom {
+			return pse.Enabled
+		}
+	}
+	return p.DefaultSendEnabled
+}
+
+// SetSendEnabledParam returns an updated set of Parameters with the given denom
+// send enabled flag set.
+func (p Params) SetSendEnabledParam(denom string, sendEnabled bool) Params {
+	var sendParams SendEnabledParams
+	for _, p := range p.SendEnabled {
+		if p.Denom != denom {
+			sendParams = append(sendParams, NewSendEnabled(p.Denom, p.Enabled))
+		}
+	}
+	sendParams = append(sendParams, NewSendEnabled(denom, sendEnabled))
+	return NewParams(p.DefaultSendEnabled, sendParams)
+}
+
+// ParamSetPairs implements params.ParamSet
+func (p *Params) ParamSetPairs() paramtypes.ParamSetPairs {
+	return paramtypes.ParamSetPairs{
+		paramtypes.NewParamSetPair(KeySendEnabled, &p.SendEnabled, validateSendEnabledParams),
+		paramtypes.NewParamSetPair(KeyDefaultSendEnabled, &p.DefaultSendEnabled, validateIsBool),
+	}
+}
+
+// SendEnabledParams is a collection of parameters indicating if a coin denom is enabled for sending
+type SendEnabledParams []*SendEnabled
+
+func validateSendEnabledParams(i interface{}) error {
+	params, ok := i.([]*SendEnabled)
+	if !ok {
+		return fmt.Errorf("invalid parameter type: %T", i)
+	}
+	// ensure each denom is only registered one time.
+	registered := make(map[string]bool)
+	for _, p := range params {
+		if _, exists := registered[p.Denom]; exists {
+			return fmt.Errorf("duplicate send enabled parameter found: '%s'", p.Denom)
+		}
+		if err := validateSendEnabled(*p); err != nil {
+			return err
+		}
+		registered[p.Denom] = true
+	}
+	return nil
+}
+
+// NewSendEnabled creates a new SendEnabled object
+// The denom may be left empty to control the global default setting of send_enabled
+func NewSendEnabled(denom string, sendEnabled bool) *SendEnabled {
+	return &SendEnabled{
+		Denom:   denom,
+		Enabled: sendEnabled,
+	}
+}
+
+// String implements stringer insterface
+func (se SendEnabled) String() string {
+	out, _ := yaml.Marshal(se)
+	return string(out)
 }
 
 func validateSendEnabled(i interface{}) error {
+	param, ok := i.(SendEnabled)
+	if !ok {
+		return fmt.Errorf("invalid parameter type: %T", i)
+	}
+	return sdk.ValidateDenom(param.Denom)
+}
+
+func validateIsBool(i interface{}) error {
 	_, ok := i.(bool)
 	if !ok {
 		return fmt.Errorf("invalid parameter type: %T", i)
 	}
-
 	return nil
 }

x/bank/types/params_test.go

@@ -0,0 +1,124 @@
+package types
+
+import (
+	"testing"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_validateSendEnabledParam(t *testing.T) {
+	type args struct {
+		i interface{}
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantErr bool
+	}{
+		{"invalid type", args{sdk.NewCoin(sdk.DefaultBondDenom, sdk.OneInt())}, true},
+
+		{"invalid empty denom send enabled", args{*NewSendEnabled("", true)}, true},
+		{"invalid empty denom send disabled", args{*NewSendEnabled("", false)}, true},
+
+		{"valid denom send enabled", args{*NewSendEnabled(sdk.DefaultBondDenom, true)}, false},
+		{"valid denom send disabled", args{*NewSendEnabled(sdk.DefaultBondDenom, false)}, false},
+
+		{"invalid denom send enabled", args{*NewSendEnabled("FOO", true)}, true},
+		{"invalid denom send disabled", args{*NewSendEnabled("FOO", false)}, true},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			require.Equal(t, tt.wantErr, validateSendEnabled(tt.args.i) != nil)
+		})
+	}
+}
+
+func Test_sendParamEqual(t *testing.T) {
+	paramsA := NewSendEnabled(sdk.DefaultBondDenom, true)
+	paramsB := NewSendEnabled(sdk.DefaultBondDenom, true)
+	paramsC := NewSendEnabled("foodenom", false)
+
+	ok := paramsA.Equal(paramsB)
+	require.True(t, ok)
+
+	ok = paramsA.Equal(paramsC)
+	require.False(t, ok)
+}
+
+func Test_sendParamString(t *testing.T) {
+	paramString := "denom: foo\nenabled: false\n"
+	param := NewSendEnabled("foo", false)
+
+	require.Equal(t, paramString, param.String())
+}
+
+func Test_validateParams(t *testing.T) {
+	params := DefaultParams()
+
+	// default params have no error
+	require.NoError(t, params.Validate())
+
+	// default case is all denoms are enabled for sending
+	require.True(t, params.SendEnabledDenom(sdk.DefaultBondDenom))
+	require.True(t, params.SendEnabledDenom("foodenom"))
+
+	params.DefaultSendEnabled = false
+	params = params.SetSendEnabledParam("foodenom", true)
+
+	require.NoError(t, validateSendEnabledParams(params.SendEnabled))
+	require.True(t, params.SendEnabledDenom("foodenom"))
+	require.False(t, params.SendEnabledDenom(sdk.DefaultBondDenom))
+
+	params.DefaultSendEnabled = true
+	params = params.SetSendEnabledParam("foodenom", false)
+
+	require.NoError(t, validateSendEnabledParams(params.SendEnabled))
+	require.False(t, params.SendEnabledDenom("foodenom"))
+	require.True(t, params.SendEnabledDenom(sdk.DefaultBondDenom))
+
+	params = params.SetSendEnabledParam("foodenom", true)
+	require.True(t, params.SendEnabledDenom("foodenom"))
+
+	params = params.SetSendEnabledParam("foodenom", false)
+	require.False(t, params.SendEnabledDenom("foodenom"))
+
+	require.True(t, params.SendEnabledDenom("foodenom2"))
+	params = params.SetSendEnabledParam("foodenom2", false)
+	require.True(t, params.SendEnabledDenom(""))
+	require.True(t, params.SendEnabledDenom(sdk.DefaultBondDenom))
+	require.False(t, params.SendEnabledDenom("foodenom2"))
+
+	paramYaml := `send_enabled:
+- denom: foodenom
+  enabled: false
+- denom: foodenom2
+  enabled: false
+default_send_enabled: true
+`
+	require.Equal(t, paramYaml, params.String())
+
+	// Ensure proper format of yaml output when false
+	params.DefaultSendEnabled = false
+	paramYaml = `send_enabled:
+- denom: foodenom
+  enabled: false
+- denom: foodenom2
+  enabled: false
+`
+	require.Equal(t, paramYaml, params.String())
+
+	params = NewParams(true, SendEnabledParams{
+		NewSendEnabled("foodenom", false),
+		NewSendEnabled("foodenom", true), // this is not allowed
+	})
+
+	// fails due to duplicate entries.
+	require.Error(t, params.Validate())
+
+	// fails due to invalid type
+	require.Error(t, validateSendEnabledParams(NewSendEnabled("foodenom", true)))
+
+	require.Error(t, validateSendEnabledParams(SendEnabledParams{NewSendEnabled("INVALIDDENOM", true)}))
+}

x/slashing/keeper/grpc_query_test.go

@@ -13,6 +13,7 @@ import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/types/query"
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
+	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
 	"github.com/cosmos/cosmos-sdk/x/slashing/keeper"
 	"github.com/cosmos/cosmos-sdk/x/slashing/types"
 )
@@ -31,7 +32,7 @@ func (suite *SlashingTestSuite) SetupTest() {
 	ctx := app.BaseApp.NewContext(false, abci.Header{})
 
 	app.AccountKeeper.SetParams(ctx, authtypes.DefaultParams())
-	app.BankKeeper.SetSendEnabled(ctx, true)
+	app.BankKeeper.SetParams(ctx, banktypes.DefaultParams())
 	app.SlashingKeeper.SetParams(ctx, keeper.TestParams())
 
 	addrDels := simapp.AddTestAddrsIncremental(app, ctx, 2, sdk.TokensFromConsensusPower(200))