feat(ante): skip fees for IBC messages

README.md

@@ -106,6 +106,7 @@ export HUB_RPC_ENDPOINT="http://localhost"
 export HUB_RPC_PORT="36657" # default: 36657
 export HUB_RPC_URL="${HUB_RPC_ENDPOINT}:${HUB_RPC_PORT}"
 export HUB_CHAIN_ID="dymension_100-1"
+export HUB_REST_URL="localhost:1318" # required for relayer
 
 dymd config chain-id ${HUB_CHAIN_ID}
 dymd config node ${HUB_RPC_URL}
@@ -140,7 +141,7 @@ NEW_NUMERIC_PART=$(echo "$NUMERIC_PART + 100000000000000000000" | bc)
 # Append 'adym' back
 TRANSFER_AMOUNT="${NEW_NUMERIC_PART}adym"
 
-dymd tx bank send $HUB_KEY_WITH_FUNDS $SEQUENCER_ADDR ${TRANSFER_AMOUNT} --keyring-backend test --broadcast-mode block --fees 1dym -y --node ${HUB_RPC_URL} --chain-id ${HUB_CHAIN_ID}
+dymd tx bank send $HUB_KEY_WITH_FUNDS $SEQUENCER_ADDR ${TRANSFER_AMOUNT} --keyring-backend test --fees 1dym -y --node ${HUB_RPC_URL} --chain-id ${HUB_CHAIN_ID}
 ```
 
 ### Generate denommetadata
@@ -170,22 +171,14 @@ sh scripts/settlement/register_sequencer_to_hub.sh
 ### Configure the rollapp
 
 Modify `dymint.toml` in the chain directory (`~/.rollapp/config`)
-set:
-
-linux:
-
-```shell
-sed -i 's/settlement_layer.*/settlement_layer = "dymension"/' ${ROLLAPP_HOME_DIR}/config/dymint.toml
-sed -i '/node_address =/c\node_address = '\"$HUB_RPC_URL\" "${ROLLAPP_HOME_DIR}/config/dymint.toml"
-sed -i '/rollapp_id =/c\rollapp_id = '\"$ROLLAPP_CHAIN_ID\" "${ROLLAPP_HOME_DIR}/config/dymint.toml"
-```
-
-mac:
 
 ```shell
-sed -i '' 's/settlement_layer.*/settlement_layer = "dymension"/' ${ROLLAPP_HOME_DIR}/config/dymint.toml
-sed -i '' 's|node_address =.*|node_address = '\"$HUB_RPC_URL\"'|' "${ROLLAPP_HOME_DIR}/config/dymint.toml"
-sed -i '' 's|rollapp_id =.*|rollapp_id = '\"$ROLLAPP_CHAIN_ID\"'|' "${ROLLAPP_HOME_DIR}/config/dymint.toml"
+dasel put -f "${ROLLAPP_HOME_DIR}"/config/dymint.toml "settlement_layer" -v "dymension"
+dasel put -f "${ROLLAPP_HOME_DIR}"/config/dymint.toml "node_address" -v "$HUB_RPC_URL"
+dasel put -f "${ROLLAPP_HOME_DIR}"/config/dymint.toml "rollapp_id" -v "$ROLLAPP_CHAIN_ID"
+dasel put -f "${ROLLAPP_HOME_DIR}"/config/dymint.toml "max_idle_time" -v "2s"
+dasel put -f "${ROLLAPP_HOME_DIR}"/config/dymint.toml "max_proof_time" -v "1s"
+dasel put -f "${ROLLAPP_HOME_DIR}"/config/app.toml "minimum-gas-prices" -v "1awsm"
 ```
 
 ### Run rollapp locally

app/ante.go

@@ -47,12 +47,13 @@ func GetAnteDecorators(options HandlerOptions) []sdk.AnteDecorator {
 		ante.NewTxTimeoutHeightDecorator(),
 
 		ante.NewValidateMemoDecorator(options.AccountKeeper),
+		NewCreateAccountDecorator(options.AccountKeeper.(accountKeeper)),
 		ante.NewConsumeGasForTxSizeDecorator(options.AccountKeeper),
-		gasless.NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper, options.TxFeeChecker, options.GaslessKeeper),
+		NewBypassIBCFeeDecorator(gasless.NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper, options.TxFeeChecker, options.GaslessKeeper)),
 		ante.NewSetPubKeyDecorator(options.AccountKeeper), // SetPubKeyDecorator must be called before all signature verification decorators
 		ante.NewValidateSigCountDecorator(options.AccountKeeper),
 		ante.NewSigGasConsumeDecorator(options.AccountKeeper, sigGasConsumer),
-		ante.NewSigVerificationDecorator(options.AccountKeeper, options.SignModeHandler),
+		NewSigCheckDecorator(options.AccountKeeper.(accountKeeper), options.SignModeHandler),
 		ante.NewIncrementSequenceDecorator(options.AccountKeeper),
 	}
 

app/bypass_ibc_fee_decorator.go

@@ -0,0 +1,66 @@
+package app
+
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	clienttypes "github.com/cosmos/ibc-go/v6/modules/core/02-client/types"
+	conntypes "github.com/cosmos/ibc-go/v6/modules/core/03-connection/types"
+	channeltypes "github.com/cosmos/ibc-go/v6/modules/core/04-channel/types"
+)
+
+type anteHandler interface {
+	AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (sdk.Context, error)
+}
+
+type BypassIBCFeeDecorator struct {
+	nextAnte anteHandler
+}
+
+func NewBypassIBCFeeDecorator(nextAnte anteHandler) BypassIBCFeeDecorator {
+	return BypassIBCFeeDecorator{nextAnte: nextAnte}
+}
+
+// SKIP FEE DEDUCT and MIN GAS PRICE Ante handlers for IBC relayer messages
+func (n BypassIBCFeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (sdk.Context, error) {
+	// ======== HACK ================
+	if isIBCRelayerMsg(tx.GetMsgs()) {
+		return next(ctx, tx, simulate)
+	}
+	// ==============================
+
+	// If it's not an IBC Relayer transfer, proceed with the default fee handling
+	return n.nextAnte.AnteHandle(ctx, tx, simulate, next)
+}
+
+// isIBCRelayerMsg checks if all the messages in the transaction are IBC relayer messages
+func isIBCRelayerMsg(msgs []sdk.Msg) bool {
+	isIBCRelayer := false
+
+	for _, msg := range msgs {
+		switch msg.(type) {
+		// IBC Client Messages
+		case *clienttypes.MsgCreateClient, *clienttypes.MsgUpdateClient,
+			*clienttypes.MsgUpgradeClient, *clienttypes.MsgSubmitMisbehaviour:
+			isIBCRelayer = true
+
+		// IBC Connection Messages
+		case *conntypes.MsgConnectionOpenInit, *conntypes.MsgConnectionOpenTry,
+			*conntypes.MsgConnectionOpenAck, *conntypes.MsgConnectionOpenConfirm:
+			isIBCRelayer = true
+
+		// IBC Channel Messages
+		case *channeltypes.MsgChannelOpenInit, *channeltypes.MsgChannelOpenTry,
+			*channeltypes.MsgChannelOpenAck, *channeltypes.MsgChannelOpenConfirm,
+			*channeltypes.MsgChannelCloseInit, *channeltypes.MsgChannelCloseConfirm:
+			isIBCRelayer = true
+
+		// IBC Packet Messages
+		case *channeltypes.MsgRecvPacket, *channeltypes.MsgAcknowledgement,
+			*channeltypes.MsgTimeout, *channeltypes.MsgTimeoutOnClose:
+			isIBCRelayer = true
+		default:
+			return false
+		}
+	}
+
+	return isIBCRelayer
+}

app/create_account_decorator.go

@@ -0,0 +1,67 @@
+package app
+
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
+	authsigning "github.com/cosmos/cosmos-sdk/x/auth/signing"
+	"github.com/cosmos/cosmos-sdk/x/auth/types"
+)
+
+type createAccountDecorator struct {
+	ak accountKeeper
+}
+
+type accountKeeper interface {
+	authante.AccountKeeper
+	NewAccountWithAddress(ctx sdk.Context, addr sdk.AccAddress) types.AccountI
+}
+
+func NewCreateAccountDecorator(ak accountKeeper) createAccountDecorator {
+	return createAccountDecorator{ak: ak}
+}
+
+const newAccountCtxKeyPrefix = "new-account/"
+
+func CtxKeyNewAccount(acc string) string {
+	return newAccountCtxKeyPrefix + acc
+}
+
+func (cad createAccountDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (sdk.Context, error) {
+	sigTx, ok := tx.(authsigning.SigVerifiableTx)
+	if !ok {
+		return ctx, sdkerrors.Wrap(sdkerrors.ErrTxDecode, "invalid tx type")
+	}
+
+	pubkeys, err := sigTx.GetPubKeys()
+	if err != nil {
+		return ctx, err
+	}
+
+	ibcRelayerMsg := isIBCRelayerMsg(tx.GetMsgs())
+
+	for i, pk := range pubkeys {
+		if pk == nil {
+			continue
+		}
+
+		acc, err := authante.GetSignerAcc(ctx, cad.ak, sigTx.GetSigners()[i])
+		if err != nil {
+			// ======= HACK =========================
+			// for IBC relayer messages, create an account if it doesn't exist
+			if ibcRelayerMsg {
+				address := sdk.AccAddress(pk.Address())
+				acc = cad.ak.NewAccountWithAddress(ctx, address)
+				// inject the new account flag into the context, in order to signal
+				// the account creation to the subsequent decorators (sigchecker)
+				ctx = ctx.WithValue(CtxKeyNewAccount(address.String()), struct{}{})
+				cad.ak.SetAccount(ctx, acc)
+			} else {
+				return ctx, err
+			}
+			// ======================================
+		}
+	}
+
+	return next(ctx, tx, simulate)
+}

app/sigcheck_decorator.go

@@ -0,0 +1,105 @@
+package app
+
+import (
+	"fmt"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
+	authsigning "github.com/cosmos/cosmos-sdk/x/auth/signing"
+)
+
+type sigCheckDecorator struct {
+	ak              accountKeeper
+	signModeHandler authsigning.SignModeHandler
+}
+
+func NewSigCheckDecorator(ak accountKeeper, signModeHandler authsigning.SignModeHandler) sigCheckDecorator {
+	return sigCheckDecorator{ak: ak, signModeHandler: signModeHandler}
+}
+
+// Copied from github.com/cosmos/[email protected]/x/auth/ante/sigverify.go:235
+// and modified to set account number to 0 when verifying for IBC relayer messages from a new account
+func (svd sigCheckDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
+	sigTx, ok := tx.(authsigning.SigVerifiableTx)
+	if !ok {
+		return ctx, sdkerrors.Wrap(sdkerrors.ErrTxDecode, "invalid transaction type")
+	}
+
+	// stdSigs contains the sequence number, account number, and signatures.
+	// When simulating, this would just be a 0-length slice.
+	sigs, err := sigTx.GetSignaturesV2()
+	if err != nil {
+		return ctx, err
+	}
+
+	signerAddrs := sigTx.GetSigners()
+
+	// check that signer length and signature length are the same
+	if len(sigs) != len(signerAddrs) {
+		return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnauthorized, "invalid number of signer;  expected: %d, got %d", len(signerAddrs), len(sigs))
+	}
+
+	ibcRelayerMsg := isIBCRelayerMsg(tx.GetMsgs())
+
+	for i, sig := range sigs {
+		acc, err := authante.GetSignerAcc(ctx, svd.ak, signerAddrs[i])
+		if err != nil {
+			return ctx, err
+		}
+
+		// retrieve pubkey
+		pubKey := acc.GetPubKey()
+		if !simulate && pubKey == nil {
+			return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidPubKey, "pubkey on account is not set")
+		}
+
+		// Check account sequence number.
+		if sig.Sequence != acc.GetSequence() {
+			return ctx, sdkerrors.Wrapf(
+				sdkerrors.ErrWrongSequence,
+				"account sequence mismatch, expected %d, got %d", acc.GetSequence(), sig.Sequence,
+			)
+		}
+
+		// retrieve signer data
+		genesis := ctx.BlockHeight() == 0
+		chainID := ctx.ChainID()
+		var accNum uint64
+
+		// ======= HACK ====================
+		_, isNewAcc := ctx.Value(CtxKeyNewAccount(acc.GetAddress().String())).(struct{})
+		isNewRelayerAcc := ibcRelayerMsg && isNewAcc
+		if !genesis && !isNewRelayerAcc {
+			accNum = acc.GetAccountNumber()
+		}
+		// =================================
+
+		signerData := authsigning.SignerData{
+			Address:       acc.GetAddress().String(),
+			ChainID:       chainID,
+			AccountNumber: accNum,
+			Sequence:      acc.GetSequence(),
+			PubKey:        pubKey,
+		}
+
+		// no need to verify signatures on recheck tx
+		if !simulate && !ctx.IsReCheckTx() {
+			err := authsigning.VerifySignature(pubKey, signerData, sig.Data, svd.signModeHandler, tx)
+			if err != nil {
+				var errMsg string
+				if authante.OnlyLegacyAminoSigners(sig.Data) {
+					// If all signers are using SIGN_MODE_LEGACY_AMINO, we rely on VerifySignature to check account sequence number,
+					// and therefore communicate sequence number as a potential cause of error.
+					errMsg = fmt.Sprintf("signature verification failed; please verify account number (%d), sequence (%d) and chain-id (%s)", accNum, acc.GetSequence(), chainID)
+				} else {
+					errMsg = fmt.Sprintf("signature verification failed; please verify account number (%d) and chain-id (%s)", accNum, chainID)
+				}
+				return ctx, sdkerrors.Wrap(sdkerrors.ErrUnauthorized, errMsg)
+
+			}
+		}
+	}
+
+	return next(ctx, tx, simulate)
+}