Emint tx type for eth_call and logs setup (#118)

* Implement new tx message type for eth_call and module txs and abstracted state transition, prepared db for logs

* Added transaction indexing to evm keeper

* Alternative count type

x/evm/handler.go

@@ -3,15 +3,15 @@ package evm
 import (
 	"fmt"
 	"math/big"
-	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core"
-	"github.com/ethereum/go-ethereum/core/vm"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	authutils "github.com/cosmos/cosmos-sdk/x/auth/client/utils"
 	emint "github.com/cosmos/ethermint/types"
 	"github.com/cosmos/ethermint/x/evm/types"
+
+	tm "github.com/tendermint/tendermint/types"
 )
 
 // NewHandler returns a handler for Ethermint type messages.
@@ -20,6 +20,8 @@ func NewHandler(keeper Keeper) sdk.Handler {
 		switch msg := msg.(type) {
 		case types.EthereumTxMsg:
 			return handleETHTxMsg(ctx, keeper, msg)
+		case types.EmintMsg:
+			return handleEmintMsg(ctx, keeper, msg)
 		default:
 			errMsg := fmt.Sprintf("Unrecognized ethermint Msg type: %v", msg.Type())
 			return sdk.ErrUnknownRequest(errMsg).Result()
@@ -44,82 +46,64 @@ func handleETHTxMsg(ctx sdk.Context, keeper Keeper, msg types.EthereumTxMsg) sdk
 	if err != nil {
 		return emint.ErrInvalidSender(err.Error()).Result()
 	}
-	contractCreation := msg.To() == nil
 
-	// Pay intrinsic gas
-	// TODO: Check config for homestead enabled
-	cost, err := core.IntrinsicGas(msg.Data.Payload, contractCreation, true)
+	st := types.StateTransition{
+		Sender:       sender,
+		AccountNonce: msg.Data.AccountNonce,
+		Price:        msg.Data.Price,
+		GasLimit:     msg.Data.GasLimit,
+		Recipient:    msg.Data.Recipient,
+		Amount:       msg.Data.Amount,
+		Payload:      msg.Data.Payload,
+		Csdb:         keeper.csdb,
+		ChainID:      intChainID,
+	}
+
+	// Encode transaction by default Tx encoder
+	txEncoder := authutils.GetTxEncoder(types.ModuleCdc)
+	txBytes, err := txEncoder(msg)
 	if err != nil {
-		return emint.ErrInvalidIntrinsicGas(err.Error()).Result()
+		return sdk.ErrInternal(err.Error()).Result()
 	}
+	txHash := tm.Tx(txBytes).Hash()
 
-	usableGas := msg.Data.GasLimit - cost
+	// Prepare db for logs
+	keeper.csdb.Prepare(common.BytesToHash(txHash), common.Hash{}, keeper.txCount.get())
+	keeper.txCount.increment()
 
-	// Create context for evm
-	context := vm.Context{
-		CanTransfer: core.CanTransfer,
-		Transfer:    core.Transfer,
-		Origin:      sender,
-		Coinbase:    common.Address{},
-		BlockNumber: big.NewInt(ctx.BlockHeight()),
-		Time:        big.NewInt(time.Now().Unix()),
-		Difficulty:  big.NewInt(0x30000), // unused
-		GasLimit:    ctx.GasMeter().Limit(),
-		GasPrice:    ctx.MinGasPrices().AmountOf(emint.DenomDefault).Int,
-	}
-
-	vmenv := vm.NewEVM(context, keeper.csdb.WithContext(ctx), types.GenerateChainConfig(intChainID), vm.Config{})
-
-	var (
-		leftOverGas uint64
-		addr        common.Address
-		vmerr       error
-		senderRef   = vm.AccountRef(sender)
-	)
-
-	if contractCreation {
-		_, addr, leftOverGas, vmerr = vmenv.Create(senderRef, msg.Data.Payload, usableGas, msg.Data.Amount)
-	} else {
-		// Increment the nonce for the next transaction
-		keeper.csdb.SetNonce(sender, keeper.csdb.GetNonce(sender)+1)
-		_, leftOverGas, vmerr = vmenv.Call(senderRef, *msg.To(), msg.Data.Payload, usableGas, msg.Data.Amount)
-	}
-
-	// handle errors
-	if vmerr != nil {
-		return emint.ErrVMExecution(vmerr.Error()).Result()
-	}
-
-	// Refund remaining gas from tx (Check these values and ensure gas is being consumed correctly)
-	refundGas(keeper.csdb, &leftOverGas, msg.Data.GasLimit, context.GasPrice, sender)
-
-	// add balance for the processor of the tx (determine who rewards are being processed to)
-	// TODO: Double check nothing needs to be done here
-
-	keeper.csdb.Finalise(true) // Change to depend on config
-
-	// TODO: Consume gas from sender
-
-	return sdk.Result{Data: addr.Bytes(), GasUsed: msg.Data.GasLimit - leftOverGas}
+	return st.TransitionCSDB(ctx)
 }
 
-func refundGas(
-	st vm.StateDB, gasRemaining *uint64, initialGas uint64, gasPrice *big.Int,
-	from common.Address,
-) {
-	// Apply refund counter, capped to half of the used gas.
-	refund := (initialGas - *gasRemaining) / 2
-	if refund > st.GetRefund() {
-		refund = st.GetRefund()
+func handleEmintMsg(ctx sdk.Context, keeper Keeper, msg types.EmintMsg) sdk.Result {
+	if err := msg.ValidateBasic(); err != nil {
+		return err.Result()
 	}
-	*gasRemaining += refund
 
-	// Return ETH for remaining gas, exchanged at the original rate.
-	remaining := new(big.Int).Mul(new(big.Int).SetUint64(*gasRemaining), gasPrice)
-	st.AddBalance(from, remaining)
+	// parse the chainID from a string to a base-10 integer
+	intChainID, ok := new(big.Int).SetString(ctx.ChainID(), 10)
+	if !ok {
+		return emint.ErrInvalidChainID(fmt.Sprintf("invalid chainID: %s", ctx.ChainID())).Result()
+	}
 
-	// // Also return remaining gas to the block gas counter so it is
-	// // available for the next transaction.
-	// TODO: Return gas to block gas meter?
-	// st.gp.AddGas(st.gas)
+	st := types.StateTransition{
+		Sender:       common.BytesToAddress(msg.From.Bytes()),
+		AccountNonce: msg.AccountNonce,
+		Price:        msg.Price.BigInt(),
+		GasLimit:     msg.GasLimit,
+		Amount:       msg.Amount.BigInt(),
+		Payload:      msg.Payload,
+		Csdb:         keeper.csdb,
+		ChainID:      intChainID,
+	}
+
+	if msg.Recipient != nil {
+		to := common.BytesToAddress(msg.Recipient.Bytes())
+		st.Recipient = &to
+	}
+
+	// Prepare db for logs
+	keeper.csdb.Prepare(common.Hash{}, common.Hash{}, keeper.txCount.get()) // Cannot provide tx hash
+	keeper.txCount.increment()
+
+	return st.TransitionCSDB(ctx)
 }

x/evm/keeper.go

@@ -23,6 +23,21 @@ type Keeper struct {
 	csdb     *types.CommitStateDB
 	cdc      *codec.Codec
 	blockKey sdk.StoreKey
+	txCount  *count
+}
+
+type count int
+
+func (c *count) get() int {
+	return (int)(*c)
+}
+
+func (c *count) increment() {
+	*c = *c + 1
+}
+
+func (c *count) reset() {
+	*c = 0
 }
 
 // NewKeeper generates new evm module keeper
@@ -32,6 +47,7 @@ func NewKeeper(ak auth.AccountKeeper, storageKey, codeKey sdk.StoreKey,
 		csdb:     types.NewCommitStateDB(sdk.Context{}, ak, storageKey, codeKey),
 		cdc:      cdc,
 		blockKey: blockKey,
+		txCount:  new(count),
 	}
 }
 
@@ -53,7 +69,7 @@ func (k *Keeper) GetBlockHashMapping(ctx sdk.Context, hash []byte) (height int64
 	store := ctx.KVStore(k.blockKey)
 	bz := store.Get(hash)
 	if bytes.Equal(bz, []byte{}) {
-		panic(fmt.Errorf("block with hash %s not found", ethcmn.Bytes2Hex(hash)))
+		panic(fmt.Errorf("block with hash %s not found", ethcmn.BytesToHash(hash)))
 	}
 	k.cdc.MustUnmarshalBinaryLengthPrefixed(bz, &height)
 	return

x/evm/module.go

@@ -107,6 +107,7 @@ func (am AppModule) NewQuerierHandler() sdk.Querier {
 func (am AppModule) BeginBlock(ctx sdk.Context, bl abci.RequestBeginBlock) {
 	// Consider removing this when using evm as module without web3 API
 	am.keeper.SetBlockHashMapping(ctx, bl.Header.LastBlockId.GetHash(), bl.Header.GetHeight()-1)
+	am.keeper.txCount.reset()
 }
 
 // EndBlock function for module at end of block

x/evm/types/codec.go

@@ -5,6 +5,7 @@ import (
 	"github.com/cosmos/ethermint/crypto"
 )
 
+// ModuleCdc defines the codec to be used by evm module
 var ModuleCdc = codec.New()
 
 func init() {
@@ -19,5 +20,6 @@ func init() {
 // RegisterCodec registers concrete types and interfaces on the given codec.
 func RegisterCodec(cdc *codec.Codec) {
 	cdc.RegisterConcrete(&EthereumTxMsg{}, "ethermint/MsgEthereumTx", nil)
+	cdc.RegisterConcrete(&EmintMsg{}, "ethermint/MsgEmint", nil)
 	crypto.RegisterCodec(cdc)
 }

x/evm/types/emint_msg.go

@@ -0,0 +1,88 @@
+package types
+
+import (
+	"fmt"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/ethermint/types"
+	ethcmn "github.com/ethereum/go-ethereum/common"
+)
+
+var (
+	_ sdk.Msg = EmintMsg{}
+)
+
+const (
+	// TypeEmintMsg defines the type string of Emint message
+	TypeEmintMsg = "emint_tx"
+)
+
+// EmintMsg implements a cosmos equivalent structure for Ethereum transactions
+type EmintMsg struct {
+	AccountNonce uint64          `json:"nonce"`
+	Price        sdk.Int         `json:"gasPrice"`
+	GasLimit     uint64          `json:"gas"`
+	Recipient    *sdk.AccAddress `json:"to" rlp:"nil"` // nil means contract creation
+	Amount       sdk.Int         `json:"value"`
+	Payload      []byte          `json:"input"`
+
+	// From address (formerly derived from signature)
+	From sdk.AccAddress `json:"from"`
+}
+
+// NewEmintMsg returns a reference to a new Ethermint transaction
+func NewEmintMsg(
+	nonce uint64, to *sdk.AccAddress, amount sdk.Int,
+	gasLimit uint64, gasPrice sdk.Int, payload []byte, from sdk.AccAddress,
+) EmintMsg {
+	return EmintMsg{
+		AccountNonce: nonce,
+		Price:        gasPrice,
+		GasLimit:     gasLimit,
+		Recipient:    to,
+		Amount:       amount,
+		Payload:      payload,
+		From:         from,
+	}
+}
+
+// Route should return the name of the module
+func (msg EmintMsg) Route() string { return RouterKey }
+
+// Type returns the action of the message
+func (msg EmintMsg) Type() string { return TypeEmintMsg }
+
+// GetSignBytes encodes the message for signing
+func (msg EmintMsg) GetSignBytes() []byte {
+	return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(msg))
+}
+
+// ValidateBasic runs stateless checks on the message
+func (msg EmintMsg) ValidateBasic() sdk.Error {
+	if msg.Price.Sign() != 1 {
+		return types.ErrInvalidValue(fmt.Sprintf("Price must be positive: %x", msg.Price))
+	}
+
+	// Amount can be 0
+	if msg.Amount.Sign() == -1 {
+		return types.ErrInvalidValue(fmt.Sprintf("amount cannot be negative: %x", msg.Amount))
+	}
+
+	return nil
+}
+
+// GetSigners defines whose signature is required
+func (msg EmintMsg) GetSigners() []sdk.AccAddress {
+	return []sdk.AccAddress{msg.From}
+}
+
+// To returns the recipient address of the transaction. It returns nil if the
+// transaction is a contract creation.
+func (msg EmintMsg) To() *ethcmn.Address {
+	if msg.Recipient == nil {
+		return nil
+	}
+
+	addr := ethcmn.BytesToAddress(msg.Recipient.Bytes())
+	return &addr
+}

x/evm/types/emint_msg_test.go

@@ -0,0 +1,76 @@
+package types
+
+import (
+	"testing"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/stretchr/testify/require"
+	"github.com/tendermint/tendermint/crypto/secp256k1"
+)
+
+func TestEmintMsg(t *testing.T) {
+	addr := newSdkAddress()
+	fromAddr := newSdkAddress()
+
+	msg := NewEmintMsg(0, &addr, sdk.NewInt(1), 100000, sdk.NewInt(2), []byte("test"), fromAddr)
+	require.NotNil(t, msg)
+	require.Equal(t, msg.Recipient, &addr)
+
+	require.Equal(t, msg.Route(), RouterKey)
+	require.Equal(t, msg.Type(), TypeEmintMsg)
+}
+
+func TestEmintMsgValidation(t *testing.T) {
+	testCases := []struct {
+		nonce      uint64
+		to         *sdk.AccAddress
+		amount     sdk.Int
+		gasLimit   uint64
+		gasPrice   sdk.Int
+		payload    []byte
+		expectPass bool
+		from       sdk.AccAddress
+	}{
+		{amount: sdk.NewInt(100), gasPrice: sdk.NewInt(100000), expectPass: true},
+		{amount: sdk.NewInt(0), gasPrice: sdk.NewInt(100000), expectPass: true},
+		{amount: sdk.NewInt(-1), gasPrice: sdk.NewInt(100000), expectPass: false},
+		{amount: sdk.NewInt(100), gasPrice: sdk.NewInt(-1), expectPass: false},
+	}
+
+	for i, tc := range testCases {
+		msg := NewEmintMsg(tc.nonce, tc.to, tc.amount, tc.gasLimit, tc.gasPrice, tc.payload, tc.from)
+
+		if tc.expectPass {
+			require.Nil(t, msg.ValidateBasic(), "test: %v", i)
+		} else {
+			require.NotNil(t, msg.ValidateBasic(), "test: %v", i)
+		}
+	}
+}
+
+func TestEmintEncodingAndDecoding(t *testing.T) {
+	addr := newSdkAddress()
+	fromAddr := newSdkAddress()
+
+	msg := NewEmintMsg(0, &addr, sdk.NewInt(1), 100000, sdk.NewInt(2), []byte("test"), fromAddr)
+
+	raw, err := cdc.MarshalBinaryBare(msg)
+	require.NoError(t, err)
+
+	var msg2 EmintMsg
+	err = cdc.UnmarshalBinaryBare(raw, &msg2)
+	require.NoError(t, err)
+
+	require.Equal(t, msg.AccountNonce, msg2.AccountNonce)
+	require.Equal(t, msg.Recipient, msg2.Recipient)
+	require.Equal(t, msg.Amount, msg2.Amount)
+	require.Equal(t, msg.GasLimit, msg2.GasLimit)
+	require.Equal(t, msg.Price, msg2.Price)
+	require.Equal(t, msg.Payload, msg2.Payload)
+	require.Equal(t, msg.From, msg2.From)
+}
+
+func newSdkAddress() sdk.AccAddress {
+	tmpKey := secp256k1.GenPrivKey().PubKey()
+	return sdk.AccAddress(tmpKey.Address().Bytes())
+}

x/evm/types/state_transition.go

@@ -0,0 +1,99 @@
+package types
+
+import (
+	"math/big"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/vm"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	emint "github.com/cosmos/ethermint/types"
+)
+
+// StateTransition defines data to transitionDB in evm
+type StateTransition struct {
+	Sender       common.Address
+	AccountNonce uint64
+	Price        *big.Int
+	GasLimit     uint64
+	Recipient    *common.Address
+	Amount       *big.Int
+	Payload      []byte
+	Csdb         *CommitStateDB
+	ChainID      *big.Int
+}
+
+// TransitionCSDB performs an evm state transition from a transaction
+func (st StateTransition) TransitionCSDB(ctx sdk.Context) sdk.Result {
+	contractCreation := st.Recipient == nil
+
+	// Create context for evm
+	context := vm.Context{
+		CanTransfer: core.CanTransfer,
+		Transfer:    core.Transfer,
+		Origin:      st.Sender,
+		Coinbase:    common.Address{},
+		BlockNumber: big.NewInt(ctx.BlockHeight()),
+		Time:        big.NewInt(time.Now().Unix()),
+		Difficulty:  big.NewInt(0x30000), // unused
+		GasLimit:    ctx.GasMeter().Limit(),
+		GasPrice:    ctx.MinGasPrices().AmountOf(emint.DenomDefault).Int,
+	}
+
+	vmenv := vm.NewEVM(context, st.Csdb.WithContext(ctx), GenerateChainConfig(st.ChainID), vm.Config{})
+
+	var (
+		leftOverGas uint64
+		addr        common.Address
+		vmerr       error
+		senderRef   = vm.AccountRef(st.Sender)
+	)
+
+	if contractCreation {
+		_, addr, leftOverGas, vmerr = vmenv.Create(senderRef, st.Payload, st.GasLimit, st.Amount)
+	} else {
+		// Increment the nonce for the next transaction
+		st.Csdb.SetNonce(st.Sender, st.Csdb.GetNonce(st.Sender)+1)
+		_, leftOverGas, vmerr = vmenv.Call(senderRef, *st.Recipient, st.Payload, st.GasLimit, st.Amount)
+	}
+
+	// handle errors
+	if vmerr != nil {
+		return emint.ErrVMExecution(vmerr.Error()).Result()
+	}
+
+	// Refund remaining gas from tx (Check these values and ensure gas is being consumed correctly)
+	refundGas(st.Csdb, &leftOverGas, st.GasLimit, context.GasPrice, st.Sender)
+
+	// add balance for the processor of the tx (determine who rewards are being processed to)
+	// TODO: Double check nothing needs to be done here
+
+	st.Csdb.Finalise(true) // Change to depend on config
+
+	// TODO: Consume gas from sender
+
+	return sdk.Result{Data: addr.Bytes(), GasUsed: st.GasLimit - leftOverGas}
+}
+
+func refundGas(
+	st vm.StateDB, gasRemaining *uint64, initialGas uint64, gasPrice *big.Int,
+	from common.Address,
+) {
+	// Apply refund counter, capped to half of the used gas.
+	refund := (initialGas - *gasRemaining) / 2
+	if refund > st.GetRefund() {
+		refund = st.GetRefund()
+	}
+	*gasRemaining += refund
+
+	// // Return ETH for remaining gas, exchanged at the original rate.
+	// remaining := new(big.Int).Mul(new(big.Int).SetUint64(*gasRemaining), gasPrice)
+	// st.AddBalance(from, remaining)
+
+	// // Also return remaining gas to the block gas counter so it is
+	// // available for the next transaction.
+	// TODO: Return gas to block gas meter?
+	// st.gp.AddGas(st.gas)
+}

x/evm/types/statedb.go

@@ -96,6 +96,7 @@ func NewCommitStateDB(ctx sdk.Context, ak auth.AccountKeeper, storageKey, codeKe
 	}
 }
 
+// WithContext returns a Database with an updated sdk context
 func (csdb *CommitStateDB) WithContext(ctx sdk.Context) *CommitStateDB {
 	csdb.ctx = ctx
 	return csdb
@@ -372,7 +373,7 @@ func (csdb *CommitStateDB) Commit(deleteEmptyObjects bool) (root ethcmn.Hash, er
 	return
 }
 
-// Finalize finalizes the state objects (accounts) state by setting their state,
+// Finalise finalizes the state objects (accounts) state by setting their state,
 // removing the csdb destructed objects and clearing the journal as well as the
 // refunds.
 func (csdb *CommitStateDB) Finalise(deleteEmptyObjects bool) {