Validator minimum commission

.gitignore

@@ -4,4 +4,8 @@ secret.yml
 cosmoshub3.json
 exchanges.json
 juno_out.json
-bin
+bin
+
+# emacs editor config
+\#*\#
+.\#*

app/ante.go

@@ -0,0 +1,97 @@
+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"
+	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
+	channelkeeper "github.com/cosmos/ibc-go/modules/core/04-channel/keeper"
+	ibcante "github.com/cosmos/ibc-go/modules/core/ante"
+)
+
+// HandlerOptions extends the SDK's AnteHandler options by requiring the IBC
+// channel keeper.
+type HandlerOptions struct {
+	ante.HandlerOptions
+
+	IBCChannelkeeper channelkeeper.Keeper
+}
+
+type MinCommissionDecorator struct{}
+
+func NewMinCommissionDecorator() MinCommissionDecorator {
+	return MinCommissionDecorator{}
+}
+
+func (MinCommissionDecorator) AnteHandle(
+	ctx sdk.Context, tx sdk.Tx,
+	simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
+	msgs := tx.GetMsgs()
+	minCommissionRate := sdk.NewDecWithPrec(5, 2)
+	for _, m := range msgs {
+		switch msg := m.(type) {
+		case *stakingtypes.MsgCreateValidator:
+			// prevent new validators joining the set with
+			// commission set below 5%
+			c := msg.Commission
+			if c.Rate.LT(minCommissionRate) {
+				return ctx, sdkerrors.Wrap(sdkerrors.ErrUnauthorized, "commission can't be lower than 5%")
+			}
+		case *stakingtypes.MsgEditValidator:
+			// if commission rate is nil, it means only
+			// other fields are affected - skip
+			if msg.CommissionRate == nil {
+				continue
+			}
+			if msg.CommissionRate.LT(minCommissionRate) {
+				return ctx, sdkerrors.Wrap(sdkerrors.ErrUnauthorized, "commission can't be lower than 5%")
+			}
+		default:
+			continue
+		}
+	}
+	return next(ctx, tx, simulate)
+}
+
+// NewAnteHandler returns an AnteHandler that checks and increments sequence
+// numbers, checks signatures & account numbers, and deducts fees from the first
+// signer.
+func NewAnteHandler(options 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")
+	}
+
+	var sigGasConsumer = options.SigGasConsumer
+	if sigGasConsumer == nil {
+		sigGasConsumer = ante.DefaultSigVerificationGasConsumer
+	}
+
+	anteDecorators := []sdk.AnteDecorator{
+		ante.NewSetUpContextDecorator(), // outermost AnteDecorator. SetUpContext must be called first
+		NewMinCommissionDecorator(),
+		ante.NewRejectExtensionOptionsDecorator(),
+		ante.NewMempoolFeeDecorator(),
+		ante.NewValidateBasicDecorator(),
+		ante.NewTxTimeoutHeightDecorator(),
+		ante.NewValidateMemoDecorator(options.AccountKeeper),
+		ante.NewConsumeGasForTxSizeDecorator(options.AccountKeeper),
+		ante.NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper),
+		// SetPubKeyDecorator must be called before all signature verification decorators
+		ante.NewSetPubKeyDecorator(options.AccountKeeper),
+		ante.NewValidateSigCountDecorator(options.AccountKeeper),
+		ante.NewSigGasConsumeDecorator(options.AccountKeeper, sigGasConsumer),
+		ante.NewSigVerificationDecorator(options.AccountKeeper, options.SignModeHandler),
+		ante.NewIncrementSequenceDecorator(options.AccountKeeper),
+		ibcante.NewAnteDecorator(options.IBCChannelkeeper),
+	}
+
+	return sdk.ChainAnteDecorators(anteDecorators...), nil
+}

app/app.go

@@ -105,7 +105,6 @@ import (
 const (
 	AccountAddressPrefix = "juno"
 	Name                 = "juno"
-	upgradeName          = "moneta-alpha"
 )
 
 // this line is used by starport scaffolding # stargate/wasm/app/enabledProposals
@@ -524,13 +523,16 @@ func New(
 	app.MountTransientStores(tkeys)
 	app.MountMemoryStores(memKeys)
 
-	anteHandler, err := ante.NewAnteHandler(
-		ante.HandlerOptions{
-			AccountKeeper:   app.AccountKeeper,
-			BankKeeper:      app.BankKeeper,
-			FeegrantKeeper:  app.FeeGrantKeeper,
-			SignModeHandler: encodingConfig.TxConfig.SignModeHandler(),
-			SigGasConsumer:  ante.DefaultSigVerificationGasConsumer,
+	anteHandler, err := NewAnteHandler(
+		HandlerOptions{
+			HandlerOptions: ante.HandlerOptions{
+				AccountKeeper:   app.AccountKeeper,
+				BankKeeper:      app.BankKeeper,
+				FeegrantKeeper:  app.FeeGrantKeeper,
+				SignModeHandler: encodingConfig.TxConfig.SignModeHandler(),
+				SigGasConsumer:  ante.DefaultSigVerificationGasConsumer,
+			},
+			IBCChannelkeeper: app.IBCKeeper.ChannelKeeper,
 		},
 	)
 	if err != nil {
@@ -548,7 +550,7 @@ func New(
 		panic(err)
 	}
 
-	if upgradeInfo.Name == upgradeName && !app.UpgradeKeeper.IsSkipHeight(upgradeInfo.Height) {
+	if upgradeInfo.Name == "moneta-alpha" && !app.UpgradeKeeper.IsSkipHeight(upgradeInfo.Height) {
 		storeUpgrades := store.StoreUpgrades{
 			Added: []string{authz.ModuleName, feegrant.ModuleName, wasm.ModuleName},
 		}
@@ -702,7 +704,32 @@ func (app *App) RegisterTendermintService(clientCtx client.Context) {
 
 // RegisterUpgradeHandlers returns upgrade handlers
 func (app *App) RegisterUpgradeHandlers(cfg module.Configurator) {
-	app.UpgradeKeeper.SetUpgradeHandler(upgradeName, func(ctx sdk.Context, plan upgradetypes.Plan, vm module.VersionMap) (module.VersionMap, error) {
+	app.UpgradeKeeper.SetUpgradeHandler("moneta-alpha", func(ctx sdk.Context, plan upgradetypes.Plan, vm module.VersionMap) (module.VersionMap, error) {
+		return app.mm.RunMigrations(ctx, cfg, vm)
+	})
+
+	app.UpgradeKeeper.SetUpgradeHandler("moneta-beta", func(ctx sdk.Context, plan upgradetypes.Plan, vm module.VersionMap) (module.VersionMap, error) {
+		// force an update of validator min commission
+		validators := app.StakingKeeper.GetAllValidators(ctx)
+		// hard code this because we don't want
+		// a) a fork or
+		// b) immediate reaction with additional gov props
+		minCommissionRate := sdk.NewDecWithPrec(5, 2)
+		for _, v := range validators {
+			if v.Commission.Rate.LT(minCommissionRate) {
+				comm, err := app.StakingKeeper.UpdateValidatorCommission(
+					ctx, v, minCommissionRate)
+				if err != nil {
+					panic(err)
+				}
+				v.Commission = comm
+
+				// call the before-modification hook since we're about to update the commission
+				app.StakingKeeper.BeforeValidatorModified(ctx, v.GetOperator())
+
+				app.StakingKeeper.SetValidator(ctx, v)
+			}
+		}
 		return app.mm.RunMigrations(ctx, cfg, vm)
 	})
 }