evm: balance and nonce invariants (#661)

* evm: balance and nonce invariants

* nonce invariant

* changelog

* use iterator on export

CHANGELOG.md

@@ -37,13 +37,19 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## Unreleased
 
+### API Breaking
+
+* (evm) [\#661](https://github.com/cosmos/ethermint/pull/661) `Balance` field has been removed from the evm module's `GenesisState`.
+
 ### Improvements
 
+* (evm) [\#661](https://github.com/cosmos/ethermint/pull/661) Add invariant check for account balance and account nonce.
 * (deps) [\#654](https://github.com/cosmos/ethermint/pull/654) Bump go-ethereum version to [v1.9.25](https://github.com/ethereum/go-ethereum/releases/tag/v1.9.25)
 * (evm) [\#627](https://github.com/cosmos/ethermint/issues/627) Add extra EIPs parameter to apply custom EVM jump tables.
 
 ### Bug Fixes
 
+* (evm) [\#661](https://github.com/cosmos/ethermint/pull/661) Set nonce to the EVM account on genesis initialization.
 * (evm) [\#621](https://github.com/cosmos/ethermint/issues/621) EVM `GenesisAccount` fields now share the same format as the auth module `Account`.
 * (evm) [\#618](https://github.com/cosmos/ethermint/issues/618) Add missing EVM `Context` `GetHash` field that retrieves a the header hash from a given block height.
 * (app) [\#617](https://github.com/cosmos/ethermint/issues/617) Fix genesis export functionality.

app/ethermint.go

@@ -280,7 +280,7 @@ func NewEthermintApp(
 	app.mm.SetOrderInitGenesis(
 		auth.ModuleName, distr.ModuleName, staking.ModuleName, bank.ModuleName,
 		slashing.ModuleName, gov.ModuleName, mint.ModuleName, supply.ModuleName,
-		crisis.ModuleName, genutil.ModuleName, evidence.ModuleName, evm.ModuleName,
+		evm.ModuleName, crisis.ModuleName, genutil.ModuleName, evidence.ModuleName,
 		faucet.ModuleName,
 	)
 

x/evm/genesis.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	authexported "github.com/cosmos/cosmos-sdk/x/auth/exported"
 
 	ethcmn "github.com/ethereum/go-ethereum/common"
 
@@ -20,7 +21,6 @@ func InitGenesis(ctx sdk.Context, k Keeper, accountKeeper types.AccountKeeper, d
 	for _, account := range data.Accounts {
 		address := ethcmn.HexToAddress(account.Address)
 		accAddress := sdk.AccAddress(address.Bytes())
-
 		// check that the EVM balance the matches the account balance
 		acc := accountKeeper.GetAccount(ctx, accAddress)
 		if acc == nil {
@@ -37,17 +37,11 @@ func InitGenesis(ctx sdk.Context, k Keeper, accountKeeper types.AccountKeeper, d
 		}
 
 		evmBalance := acc.GetCoins().AmountOf(evmDenom)
-		if !evmBalance.Equal(account.Balance) {
-			panic(
-				fmt.Errorf(
-					"balance mismatch for account %s, expected %s%s, got %s%s",
-					account.Address, evmBalance, evmDenom, account.Balance, evmDenom,
-				),
-			)
-		}
 
-		k.SetBalance(ctx, address, account.Balance.BigInt())
+		k.SetNonce(ctx, address, acc.GetSequence())
+		k.SetBalance(ctx, address, evmBalance.BigInt())
 		k.SetCode(ctx, address, account.Code)
+
 		for _, storage := range account.Storage {
 			k.SetState(ctx, address, storage.Key, storage.Value)
 		}
@@ -83,12 +77,11 @@ func InitGenesis(ctx sdk.Context, k Keeper, accountKeeper types.AccountKeeper, d
 func ExportGenesis(ctx sdk.Context, k Keeper, ak types.AccountKeeper) GenesisState {
 	// nolint: prealloc
 	var ethGenAccounts []types.GenesisAccount
-	accounts := ak.GetAllAccounts(ctx)
-
-	for _, account := range accounts {
+	ak.IterateAccounts(ctx, func(account authexported.Account) bool {
 		ethAccount, ok := account.(*ethermint.EthAccount)
 		if !ok {
-			continue
+			// ignore non EthAccounts
+			return false
 		}
 
 		addr := ethAccount.EthAddress()
@@ -98,18 +91,15 @@ func ExportGenesis(ctx sdk.Context, k Keeper, ak types.AccountKeeper) GenesisSta
 			panic(err)
 		}
 
-		balanceInt := k.GetBalance(ctx, addr)
-		balance := sdk.NewIntFromBigInt(balanceInt)
-
 		genAccount := types.GenesisAccount{
 			Address: addr.String(),
-			Balance: balance,
 			Code:    k.GetCode(ctx, addr),
 			Storage: storage,
 		}
 
 		ethGenAccounts = append(ethGenAccounts, genAccount)
-	}
+		return false
+	})
 
 	config, _ := k.GetChainConfig(ctx)
 

x/evm/genesis_test.go

@@ -54,7 +54,6 @@ func (suite *EvmTestSuite) TestInitGenesis() {
 				Accounts: []types.GenesisAccount{
 					{
 						Address: address.String(),
-						Balance: sdk.OneInt(),
 						Storage: types.Storage{
 							{Key: common.BytesToHash([]byte("key")), Value: common.BytesToHash([]byte("value"))},
 						},
@@ -87,25 +86,6 @@ func (suite *EvmTestSuite) TestInitGenesis() {
 				Accounts: []types.GenesisAccount{
 					{
 						Address: address.String(),
-						Balance: sdk.OneInt(),
-					},
-				},
-			},
-			true,
-		},
-		{
-			"balance mismatch",
-			func() {
-				acc := suite.app.AccountKeeper.NewAccountWithAddress(suite.ctx, address.Bytes())
-				suite.Require().NotNil(acc)
-				suite.app.AccountKeeper.SetAccount(suite.ctx, acc)
-			},
-			types.GenesisState{
-				Params: types.DefaultParams(),
-				Accounts: []types.GenesisAccount{
-					{
-						Address: address.String(),
-						Balance: sdk.OneInt(),
 					},
 				},
 			},

x/evm/keeper/invariants.go

@@ -0,0 +1,100 @@
+package keeper
+
+import (
+	"fmt"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	authexported "github.com/cosmos/cosmos-sdk/x/auth/exported"
+
+	ethermint "github.com/cosmos/ethermint/types"
+	"github.com/cosmos/ethermint/x/evm/types"
+)
+
+const (
+	balanceInvariant = "balance"
+	nonceInvariant   = "nonce"
+)
+
+// RegisterInvariants registers the evm module invariants
+func RegisterInvariants(ir sdk.InvariantRegistry, k Keeper) {
+	ir.RegisterRoute(types.ModuleName, balanceInvariant, k.BalanceInvariant())
+	ir.RegisterRoute(types.ModuleName, nonceInvariant, k.NonceInvariant())
+}
+
+// BalanceInvariant checks that all auth module's EthAccounts in the application have the same balance
+// as the EVM one.
+func (k Keeper) BalanceInvariant() sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		var (
+			msg   string
+			count int
+		)
+
+		k.accountKeeper.IterateAccounts(ctx, func(account authexported.Account) bool {
+			ethAccount, ok := account.(*ethermint.EthAccount)
+			if !ok {
+				// ignore non EthAccounts
+				return false
+			}
+
+			evmDenom := k.GetParams(ctx).EvmDenom
+			accountBalance := ethAccount.GetCoins().AmountOf(evmDenom)
+			evmBalance := k.GetBalance(ctx, ethAccount.EthAddress())
+
+			if evmBalance.Cmp(accountBalance.BigInt()) != 0 {
+				count++
+				msg += fmt.Sprintf(
+					"\tbalance mismatch for address %s: account balance %s, evm balance %s\n",
+					account.GetAddress(), accountBalance.String(), evmBalance.String(),
+				)
+			}
+
+			return false
+		})
+
+		broken := count != 0
+
+		return sdk.FormatInvariant(
+			types.ModuleName, balanceInvariant,
+			fmt.Sprintf("account balances mismatches found %d\n%s", count, msg),
+		), broken
+	}
+}
+
+// NonceInvariant checks that all auth module's EthAccounts in the application have the same nonce
+// sequence as the EVM.
+func (k Keeper) NonceInvariant() sdk.Invariant {
+	return func(ctx sdk.Context) (string, bool) {
+		var (
+			msg   string
+			count int
+		)
+
+		k.accountKeeper.IterateAccounts(ctx, func(account authexported.Account) bool {
+			ethAccount, ok := account.(*ethermint.EthAccount)
+			if !ok {
+				// ignore non EthAccounts
+				return false
+			}
+
+			evmNonce := k.GetNonce(ctx, ethAccount.EthAddress())
+
+			if evmNonce != ethAccount.Sequence {
+				count++
+				msg += fmt.Sprintf(
+					"\nonce mismatch for address %s: account nonce %d, evm nonce %d\n",
+					account.GetAddress(), ethAccount.Sequence, evmNonce,
+				)
+			}
+
+			return false
+		})
+
+		broken := count != 0
+
+		return sdk.FormatInvariant(
+			types.ModuleName, nonceInvariant,
+			fmt.Sprintf("account nonces mismatches found %d\n%s", count, msg),
+		), broken
+	}
+}

x/evm/keeper/invariants_test.go

@@ -0,0 +1,139 @@
+package keeper_test
+
+import (
+	"math/big"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
+
+	"github.com/cosmos/ethermint/crypto/ethsecp256k1"
+	ethermint "github.com/cosmos/ethermint/types"
+
+	ethcmn "github.com/ethereum/go-ethereum/common"
+)
+
+func (suite *KeeperTestSuite) TestBalanceInvariant() {
+	privkey, err := ethsecp256k1.GenerateKey()
+	suite.Require().NoError(err)
+
+	address := ethcmn.HexToAddress(privkey.PubKey().Address().String())
+
+	testCases := []struct {
+		name      string
+		malleate  func()
+		expBroken bool
+	}{
+		{
+			"balance mismatch",
+			func() {
+				acc := suite.app.AccountKeeper.NewAccountWithAddress(suite.ctx, address.Bytes())
+				suite.Require().NotNil(acc)
+				err := acc.SetCoins(sdk.NewCoins(ethermint.NewPhotonCoinInt64(1)))
+				suite.Require().NoError(err)
+				suite.app.AccountKeeper.SetAccount(suite.ctx, acc)
+
+				suite.app.EvmKeeper.SetBalance(suite.ctx, address, big.NewInt(1000))
+			},
+			true,
+		},
+		{
+			"balance ok",
+			func() {
+				acc := suite.app.AccountKeeper.NewAccountWithAddress(suite.ctx, address.Bytes())
+				suite.Require().NotNil(acc)
+				err := acc.SetCoins(sdk.NewCoins(ethermint.NewPhotonCoinInt64(1)))
+				suite.Require().NoError(err)
+				suite.app.AccountKeeper.SetAccount(suite.ctx, acc)
+
+				suite.app.EvmKeeper.SetBalance(suite.ctx, address, big.NewInt(1))
+			},
+			false,
+		},
+		{
+			"invalid account type",
+			func() {
+				acc := authtypes.NewBaseAccountWithAddress(address.Bytes())
+				suite.app.AccountKeeper.SetAccount(suite.ctx, &acc)
+			},
+			false,
+		},
+	}
+
+	for _, tc := range testCases {
+		suite.Run(tc.name, func() {
+			suite.SetupTest() // reset values
+
+			tc.malleate()
+
+			_, broken := suite.app.EvmKeeper.BalanceInvariant()(suite.ctx)
+			if tc.expBroken {
+				suite.Require().True(broken)
+			} else {
+				suite.Require().False(broken)
+			}
+		})
+	}
+}
+
+func (suite *KeeperTestSuite) TestNonceInvariant() {
+	privkey, err := ethsecp256k1.GenerateKey()
+	suite.Require().NoError(err)
+
+	address := ethcmn.HexToAddress(privkey.PubKey().Address().String())
+
+	testCases := []struct {
+		name      string
+		malleate  func()
+		expBroken bool
+	}{
+		{
+			"nonce mismatch",
+			func() {
+				acc := suite.app.AccountKeeper.NewAccountWithAddress(suite.ctx, address.Bytes())
+				suite.Require().NotNil(acc)
+				err := acc.SetSequence(1)
+				suite.Require().NoError(err)
+				suite.app.AccountKeeper.SetAccount(suite.ctx, acc)
+
+				suite.app.EvmKeeper.SetNonce(suite.ctx, address, 100)
+			},
+			true,
+		},
+		{
+			"nonce ok",
+			func() {
+				acc := suite.app.AccountKeeper.NewAccountWithAddress(suite.ctx, address.Bytes())
+				suite.Require().NotNil(acc)
+				err := acc.SetSequence(1)
+				suite.Require().NoError(err)
+				suite.app.AccountKeeper.SetAccount(suite.ctx, acc)
+
+				suite.app.EvmKeeper.SetNonce(suite.ctx, address, 1)
+			},
+			false,
+		},
+		{
+			"invalid account type",
+			func() {
+				acc := authtypes.NewBaseAccountWithAddress(address.Bytes())
+				suite.app.AccountKeeper.SetAccount(suite.ctx, &acc)
+			},
+			false,
+		},
+	}
+
+	for _, tc := range testCases {
+		suite.Run(tc.name, func() {
+			suite.SetupTest() // reset values
+
+			tc.malleate()
+
+			_, broken := suite.app.EvmKeeper.NonceInvariant()(suite.ctx)
+			if tc.expBroken {
+				suite.Require().True(broken)
+			} else {
+				suite.Require().False(broken)
+			}
+		})
+	}
+}

x/evm/keeper/keeper.go

@@ -30,6 +30,8 @@ type Keeper struct {
 	// - storing block height -> bloom filter map. Needed for the Web3 API.
 	// - storing block hash -> block height map. Needed for the Web3 API.
 	storeKey sdk.StoreKey
+	// Account Keeper for fetching accounts
+	accountKeeper types.AccountKeeper
 	// Ethermint concrete implementation on the EVM StateDB interface
 	CommitStateDB *types.CommitStateDB
 	// Transaction counter in a block. Used on StateSB's Prepare function.
@@ -52,6 +54,7 @@ func NewKeeper(
 	return Keeper{
 		cdc:           cdc,
 		storeKey:      storeKey,
+		accountKeeper: ak,
 		CommitStateDB: types.NewCommitStateDB(sdk.Context{}, storeKey, paramSpace, ak),
 		TxCount:       0,
 		Bloom:         big.NewInt(0),

x/evm/keeper/querier.go

@@ -197,12 +197,8 @@ func queryExportAccount(ctx sdk.Context, path []string, keeper Keeper) ([]byte,
 		return nil, err
 	}
 
-	balanceInt := keeper.GetBalance(ctx, addr)
-	balance := sdk.NewIntFromBigInt(balanceInt)
-
 	res := types.GenesisAccount{
 		Address: hexAddress,
-		Balance: balance,
 		Code:    keeper.GetCode(ctx, addr),
 		Storage: storage,
 	}

x/evm/module.go

@@ -88,7 +88,9 @@ func (AppModule) Name() string {
 }
 
 // RegisterInvariants interface for registering invariants
-func (am AppModule) RegisterInvariants(ir sdk.InvariantRegistry) {}
+func (am AppModule) RegisterInvariants(ir sdk.InvariantRegistry) {
+	keeper.RegisterInvariants(ir, am.keeper)
+}
 
 // Route specifies path for transactions
 func (am AppModule) Route() string {

x/evm/types/expected_keepers.go

@@ -9,6 +9,7 @@ import (
 type AccountKeeper interface {
 	NewAccountWithAddress(ctx sdk.Context, addr sdk.AccAddress) authexported.Account
 	GetAllAccounts(ctx sdk.Context) (accounts []authexported.Account)
+	IterateAccounts(ctx sdk.Context, cb func(account authexported.Account) bool)
 	GetAccount(ctx sdk.Context, addr sdk.AccAddress) authexported.Account
 	SetAccount(ctx sdk.Context, account authexported.Account)
 	RemoveAccount(ctx sdk.Context, account authexported.Account)

x/evm/types/genesis.go

@@ -4,8 +4,6 @@ import (
 	"errors"
 	"fmt"
 
-	sdk "github.com/cosmos/cosmos-sdk/types"
-
 	ethcmn "github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 )
@@ -22,9 +20,9 @@ type (
 	// GenesisAccount defines an account to be initialized in the genesis state.
 	// Its main difference between with Geth's GenesisAccount is that it uses a custom
 	// storage type and that it doesn't contain the private key field.
+	// NOTE: balance is omitted as it is imported from the auth account balance.
 	GenesisAccount struct {
 		Address string        `json:"address"`
-		Balance sdk.Int       `json:"balance"`
 		Code    hexutil.Bytes `json:"code,omitempty"`
 		Storage Storage       `json:"storage,omitempty"`
 	}
@@ -35,12 +33,6 @@ func (ga GenesisAccount) Validate() error {
 	if ga.Address == (ethcmn.Address{}.String()) {
 		return fmt.Errorf("address cannot be the zero address %s", ga.Address)
 	}
-	if ga.Balance.IsNil() {
-		return errors.New("balance cannot be nil")
-	}
-	if ga.Balance.IsNegative() {
-		return errors.New("balance cannot be negative")
-	}
 	if ga.Code != nil && len(ga.Code) == 0 {
 		return errors.New("code bytes cannot be empty")
 	}

x/evm/types/genesis_test.go

@@ -9,8 +9,6 @@ import (
 	ethtypes "github.com/ethereum/go-ethereum/core/types"
 	ethcrypto "github.com/ethereum/go-ethereum/crypto"
 
-	sdk "github.com/cosmos/cosmos-sdk/types"
-
 	"github.com/cosmos/ethermint/crypto/ethsecp256k1"
 )
 
@@ -26,7 +24,6 @@ func TestValidateGenesisAccount(t *testing.T) {
 			"valid genesis account",
 			GenesisAccount{
 				Address: address.String(),
-				Balance: sdk.NewInt(1),
 				Code:    []byte{1, 2, 3},
 				Storage: Storage{
 					NewState(ethcmn.BytesToHash([]byte{1, 2, 3}), ethcmn.BytesToHash([]byte{1, 2, 3})),
@@ -38,23 +35,6 @@ func TestValidateGenesisAccount(t *testing.T) {
 			"empty account address bytes",
 			GenesisAccount{
 				Address: ethcmn.Address{}.String(),
-				Balance: sdk.NewInt(1),
-			},
-			false,
-		},
-		{
-			"nil account balance",
-			GenesisAccount{
-				Address: address.String(),
-				Balance: sdk.Int{},
-			},
-			false,
-		},
-		{
-			"nil account balance",
-			GenesisAccount{
-				Address: address.String(),
-				Balance: sdk.NewInt(-1),
 			},
 			false,
 		},
@@ -62,7 +42,6 @@ func TestValidateGenesisAccount(t *testing.T) {
 			"empty code bytes",
 			GenesisAccount{
 				Address: address.String(),
-				Balance: sdk.NewInt(1),
 				Code:    []byte{},
 			},
 			false,
@@ -101,7 +80,6 @@ func TestValidateGenesis(t *testing.T) {
 				Accounts: []GenesisAccount{
 					{
 						Address: address.String(),
-						Balance: sdk.NewInt(1),
 						Code:    []byte{1, 2, 3},
 						Storage: Storage{
 							{Key: ethcmn.BytesToHash([]byte{1, 2, 3})},
@@ -153,7 +131,6 @@ func TestValidateGenesis(t *testing.T) {
 				Accounts: []GenesisAccount{
 					{
 						Address: address.String(),
-						Balance: sdk.NewInt(1),
 						Code:    []byte{1, 2, 3},
 						Storage: Storage{
 							NewState(ethcmn.BytesToHash([]byte{1, 2, 3}), ethcmn.BytesToHash([]byte{1, 2, 3})),
@@ -161,7 +138,6 @@ func TestValidateGenesis(t *testing.T) {
 					},
 					{
 						Address: address.String(),
-						Balance: sdk.NewInt(1),
 						Code:    []byte{1, 2, 3},
 						Storage: Storage{
 							NewState(ethcmn.BytesToHash([]byte{1, 2, 3}), ethcmn.BytesToHash([]byte{1, 2, 3})),
@@ -177,7 +153,6 @@ func TestValidateGenesis(t *testing.T) {
 				Accounts: []GenesisAccount{
 					{
 						Address: address.String(),
-						Balance: sdk.NewInt(1),
 						Code:    []byte{1, 2, 3},
 						Storage: Storage{
 							{Key: ethcmn.BytesToHash([]byte{1, 2, 3})},
@@ -227,7 +202,6 @@ func TestValidateGenesis(t *testing.T) {
 				Accounts: []GenesisAccount{
 					{
 						Address: address.String(),
-						Balance: sdk.NewInt(1),
 						Code:    []byte{1, 2, 3},
 						Storage: Storage{
 							{Key: ethcmn.BytesToHash([]byte{1, 2, 3})},