feat: add acknowledgePacket handler to channel/v2

modules/core/04-channel/v2/keeper/events.go

@@ -11,12 +11,17 @@ func EmitSendPacketEvents(ctx context.Context, packet channeltypesv2.Packet) {
 	// TODO: https://github.com/cosmos/ibc-go/issues/7386
 }
 
-// EmitTimeoutPacketEvents emits events for the TimeoutPacket handler.
-func EmitTimeoutPacketEvents(ctx context.Context, packet channeltypesv2.Packet) {
+// EmitRecvPacketEvents emits events for the RecvPacket handler.
+func EmitRecvPacketEvents(ctx context.Context, packet channeltypesv2.Packet) {
 	// TODO: https://github.com/cosmos/ibc-go/issues/7386
 }
 
-// EmitRecvPacketEvents emits events for the RecvPacket handler.
-func EmitRecvPacketEvents(ctx context.Context, packet channeltypesv2.Packet) {
+// EmitAcknowledgePacketEvents emits events for the AcknowledgePacket handler.
+func EmitAcknowledgePacketEvents(ctx context.Context, packet channeltypesv2.Packet, acknowledgement channeltypesv2.Acknowledgement) {
+	// TODO: https://github.com/cosmos/ibc-go/issues/7386
+}
+
+// EmitTimeoutPacketEvents emits events for the TimeoutPacket handler.
+func EmitTimeoutPacketEvents(ctx context.Context, packet channeltypesv2.Packet) {
 	// TODO: https://github.com/cosmos/ibc-go/issues/7386
 }

modules/core/04-channel/v2/keeper/keeper.go

@@ -75,17 +75,17 @@ func (k *Keeper) GetCounterparty(ctx context.Context, clientID string) (types.Co
 }
 
 // GetPacketReceipt returns the packet receipt from the packet receipt path based on the sourceID and sequence.
-func (k *Keeper) GetPacketReceipt(ctx context.Context, sourceID string, sequence uint64) (string, bool) {
+func (k *Keeper) GetPacketReceipt(ctx context.Context, sourceID string, sequence uint64) []byte {
 	store := k.storeService.OpenKVStore(ctx)
 	bigEndianBz := sdk.Uint64ToBigEndian(sequence)
 	bz, err := store.Get(hostv2.PacketReceiptKey(sourceID, bigEndianBz))
 	if err != nil {
 		panic(err)
 	}
 	if len(bz) == 0 {
-		return "", false
+		return nil
 	}
-	return string(bz), true
+	return bz
 }
 
 // SetPacketReceipt writes the packet receipt under the receipt path
@@ -121,17 +121,17 @@ func (k *Keeper) HasPacketAcknowledgement(ctx context.Context, sourceID string,
 }
 
 // GetPacketCommitment returns the packet commitment hash under the commitment path.
-func (k *Keeper) GetPacketCommitment(ctx context.Context, sourceID string, sequence uint64) (string, bool) {
+func (k *Keeper) GetPacketCommitment(ctx context.Context, sourceID string, sequence uint64) []byte {
 	store := k.storeService.OpenKVStore(ctx)
 	bigEndianBz := sdk.Uint64ToBigEndian(sequence)
 	bz, err := store.Get(hostv2.PacketCommitmentKey(sourceID, bigEndianBz))
 	if err != nil {
 		panic(err)
 	}
 	if len(bz) == 0 {
-		return "", false
+		return nil
 	}
-	return string(bz), true
+	return bz
 }
 
 // SetPacketCommitment writes the commitment hash under the commitment path.
@@ -199,3 +199,15 @@ func (k *Keeper) AliasV1Channel(ctx context.Context, portID, channelID string) (
 	}
 	return counterparty, true
 }
+
+// getV1Counterparty attempts to retrieve a v1 channel from the channel keeper if it exists, then converts it
+// to a v2 counterparty and stores it in the v2 channel keeper for future use
+func (k *Keeper) getV1Counterparty(ctx context.Context, port, id string) (types.Counterparty, bool) {
+	if counterparty, ok := k.AliasV1Channel(ctx, port, id); ok {
+		// we can key on just the channel here since channel ids are globally unique
+		k.SetCounterparty(ctx, id, counterparty)
+		return counterparty, true
+	}
+
+	return types.Counterparty{}, false
+}

modules/core/04-channel/v2/keeper/msg_server.go

@@ -43,8 +43,42 @@ func (k *Keeper) SendPacket(ctx context.Context, msg *channeltypesv2.MsgSendPack
 	return &channeltypesv2.MsgSendPacketResponse{Sequence: sequence}, nil
 }
 
-func (*Keeper) Acknowledgement(ctx context.Context, acknowledgement *channeltypesv2.MsgAcknowledgement) (*channeltypesv2.MsgAcknowledgementResponse, error) {
-	panic("implement me")
+func (k *Keeper) Acknowledgement(ctx context.Context, msg *channeltypesv2.MsgAcknowledgement) (*channeltypesv2.MsgAcknowledgementResponse, error) {
+	sdkCtx := sdk.UnwrapSDKContext(ctx)
+	relayer, err := sdk.AccAddressFromBech32(msg.Signer)
+	if err != nil {
+		sdkCtx.Logger().Error("acknowledgement failed", "error", errorsmod.Wrap(err, "Invalid address for msg Signer"))
+		return nil, errorsmod.Wrap(err, "Invalid address for msg Signer")
+	}
+
+	cacheCtx, writeFn := sdkCtx.CacheContext()
+	err = k.acknowledgePacket(cacheCtx, msg.Packet, msg.Acknowledgement, msg.ProofAcked, msg.ProofHeight)
+
+	switch err {
+	case nil:
+		writeFn()
+	case channeltypesv1.ErrNoOpMsg:
+		// no-ops do not need event emission as they will be ignored
+		sdkCtx.Logger().Debug("no-op on redundant relay", "source-id", msg.Packet.SourceId)
+		return &channeltypesv2.MsgAcknowledgementResponse{Result: channeltypesv1.NOOP}, nil
+	default:
+		sdkCtx.Logger().Error("acknowledgement failed", "source-id", msg.Packet.SourceId, "error", errorsmod.Wrap(err, "acknowledge packet verification failed"))
+		return nil, errorsmod.Wrap(err, "acknowledge packet verification failed")
+	}
+
+	_ = relayer
+
+	// TODO: implement once app router is wired up.
+	// https://github.com/cosmos/ibc-go/issues/7384
+	// for _, pd := range msg.PacketData {
+	//	cbs := k.PortKeeper.AppRouter.Route(pd.SourcePort)
+	//	err := cbs.OnSendPacket(ctx, msg.SourceId, sequence, msg.TimeoutTimestamp, pd, signer)
+	//	if err != nil {
+	//		return nil, err
+	//	}
+	// }
+
+	return nil, nil
 }
 
 // RecvPacket implements the PacketMsgServer RecvPacket method.

modules/core/04-channel/v2/keeper/relay.go → modules/core/04-channel/v2/keeper/packet.go

@@ -17,18 +17,6 @@ import (
 	"github.com/cosmos/ibc-go/v9/modules/core/packet-server/types"
 )
 
-// getV1Counterparty attempts to retrieve a v1 channel from the channel keeper if it exists, then converts it
-// to a v2 counterparty and stores it in the v2 channel keeper for future use
-func (k *Keeper) getV1Counterparty(ctx context.Context, port, id string) (channeltypesv2.Counterparty, bool) {
-	if counterparty, ok := k.AliasV1Channel(ctx, port, id); ok {
-		// we can key on just the channel here since channel ids are globally unique
-		k.SetCounterparty(ctx, id, counterparty)
-		return counterparty, true
-	}
-
-	return channeltypesv2.Counterparty{}, false
-}
-
 // sendPacket constructs a packet from the input arguments, writes a packet commitment to state
 // in order for the packet to be sent to the counterparty.
 func (k *Keeper) sendPacket(
@@ -137,8 +125,9 @@ func (k Keeper) recvPacket(
 	// REPLAY PROTECTION: Packet receipts will indicate that a packet has already been received
 	// on unordered channels. Packet receipts must not be pruned, unless it has been marked stale
 	// by the increase of the recvStartSequence.
-	_, found := k.GetPacketReceipt(ctx, packet.DestinationId, packet.Sequence)
-	if found {
+	// TODO: change to HasReceipt
+	receipt := k.GetPacketReceipt(ctx, packet.DestinationId, packet.Sequence)
+	if receipt != nil {
 		EmitRecvPacketEvents(ctx, packet)
 		// This error indicates that the packet has already been relayed. Core IBC will
 		// treat this error as a no-op in order to prevent an entire relay transaction
@@ -173,6 +162,62 @@ func (k Keeper) recvPacket(
 	return nil
 }
 
+func (k Keeper) acknowledgePacket(ctx context.Context, packet channeltypesv2.Packet, acknowledgement channeltypesv2.Acknowledgement, proof []byte, proofHeight exported.Height) error {
+	// Lookup counterparty associated with our channel and ensure
+	// that the packet was indeed sent by our counterparty.
+	counterparty, ok := k.GetCounterparty(ctx, packet.SourceId)
+	if !ok {
+		return errorsmod.Wrap(types.ErrCounterpartyNotFound, packet.SourceId)
+	}
+
+	if counterparty.ClientId != packet.DestinationId {
+		return channeltypes.ErrInvalidChannelIdentifier
+	}
+	clientID := counterparty.ClientId
+
+	commitment := k.GetPacketCommitment(ctx, packet.SourceId, packet.Sequence)
+	if len(commitment) == 0 {
+		// TODO: emit events
+		// k.EmitAcknowledgePacketEvent(ctx, packet, nil)
+
+		// This error indicates that the acknowledgement has already been relayed
+		// or there is a misconfigured relayer attempting to prove an acknowledgement
+		// for a packet never sent. Core IBC will treat this error as a no-op in order to
+		// prevent an entire relay transaction from failing and consuming unnecessary fees.
+		return channeltypes.ErrNoOpMsg
+	}
+
+	packetCommitment := channeltypesv2.CommitPacket(packet)
+
+	// verify we sent the packet and haven't cleared it out yet
+	if !bytes.Equal(commitment, packetCommitment) {
+		return errorsmod.Wrapf(channeltypes.ErrInvalidPacket, "commitment bytes are not equal: got (%v), expected (%v)", packetCommitment, commitment)
+	}
+
+	path := hostv2.PacketAcknowledgementKey(packet.DestinationId, sdk.Uint64ToBigEndian(packet.Sequence))
+	merklePath := types.BuildMerklePath(counterparty.MerklePathPrefix, path)
+
+	if err := k.ClientKeeper.VerifyMembership(
+		ctx,
+		clientID,
+		proofHeight,
+		0, 0,
+		proof,
+		merklePath,
+		channeltypesv2.CommitAcknowledgement(acknowledgement),
+	); err != nil {
+		return errorsmod.Wrapf(err, "failed packet acknowledgement verification for client (%s)", clientID)
+	}
+
+	k.DeletePacketCommitment(ctx, packet.SourceId, packet.Sequence)
+
+	k.Logger(ctx).Info("packet acknowledged", "sequence", strconv.FormatUint(packet.GetSequence(), 10), "source_id", packet.GetSourceId(), "destination_id", packet.GetDestinationId())
+
+	EmitAcknowledgePacketEvents(ctx, packet, acknowledgement)
+
+	return nil
+}
+
 // timeoutPacket implements the timeout logic required by a packet handler.
 // The packet is checked for correctness including asserting that the packet was
 // sent and received on clients which are counterparties for one another.
@@ -209,9 +254,8 @@ func (k Keeper) timeoutPacket(
 	}
 
 	// check that the commitment has not been cleared and that it matches the packet sent by relayer
-	commitment, ok := k.GetPacketCommitment(ctx, packet.SourceId, packet.Sequence)
-
-	if !ok {
+	commitment := k.GetPacketCommitment(ctx, packet.SourceId, packet.Sequence)
+	if len(commitment) == 0 {
 		EmitTimeoutPacketEvents(ctx, packet)
 		// This error indicates that the timeout has already been relayed
 		// or there is a misconfigured relayer attempting to prove a timeout
@@ -222,7 +266,7 @@ func (k Keeper) timeoutPacket(
 
 	packetCommitment := channeltypesv2.CommitPacket(packet)
 	// verify we sent the packet and haven't cleared it out yet
-	if !bytes.Equal([]byte(commitment), packetCommitment) {
+	if !bytes.Equal(commitment, packetCommitment) {
 		return errorsmod.Wrapf(channeltypes.ErrInvalidPacket, "packet commitment bytes are not equal: got (%v), expected (%v)", commitment, packetCommitment)
 	}
 

modules/core/04-channel/v2/types/commitment.go

@@ -0,0 +1,55 @@
+package types
+
+import (
+	"crypto/sha256"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+// CommitPacket returns the V2 packet commitment bytes. The commitment consists of:
+// sha256_hash(timeout) + sha256_hash(destinationID) + sha256_hash(packetData) from a given packet.
+// This results in a fixed length preimage.
+// NOTE: A fixed length preimage is ESSENTIAL to prevent relayers from being able
+// to malleate the packet fields and create a commitment hash that matches the original packet.
+func CommitPacket(packet Packet) []byte {
+	buf := sdk.Uint64ToBigEndian(packet.GetTimeoutTimestamp())
+
+	destIDHash := sha256.Sum256([]byte(packet.DestinationId))
+	buf = append(buf, destIDHash[:]...)
+
+	for _, data := range packet.Data {
+		buf = append(buf, hashPacketData(data)...)
+	}
+
+	hash := sha256.Sum256(buf)
+	return hash[:]
+}
+
+// hashPacketData returns the hash of the packet data.
+func hashPacketData(data PacketData) []byte {
+	var buf []byte
+	sourceHash := sha256.Sum256([]byte(data.SourcePort))
+	buf = append(buf, sourceHash[:]...)
+	destHash := sha256.Sum256([]byte(data.DestinationPort))
+	buf = append(buf, destHash[:]...)
+	payloadValueHash := sha256.Sum256(data.Payload.Value)
+	buf = append(buf, payloadValueHash[:]...)
+	payloadEncodingHash := sha256.Sum256([]byte(data.Payload.Encoding))
+	buf = append(buf, payloadEncodingHash[:]...)
+	payloadVersionHash := sha256.Sum256([]byte(data.Payload.Version))
+	buf = append(buf, payloadVersionHash[:]...)
+	hash := sha256.Sum256(buf)
+	return hash[:]
+}
+
+// CommitAcknowledgement returns the hash of the acknowledgement data.
+func CommitAcknowledgement(acknowledgement Acknowledgement) []byte {
+	var buf []byte
+	for _, ack := range acknowledgement.GetAcknowledgementResults() {
+		hash := sha256.Sum256(ack.RecvPacketResult.GetAcknowledgement())
+		buf = append(buf, hash[:]...)
+	}
+
+	hash := sha256.Sum256(buf)
+	return hash[:]
+}

modules/core/04-channel/v2/types/packet.go

@@ -1,13 +1,10 @@
 package types
 
 import (
-	"crypto/sha256"
 	"strings"
 
 	errorsmod "cosmossdk.io/errors"
 
-	sdk "github.com/cosmos/cosmos-sdk/types"
-
 	host "github.com/cosmos/ibc-go/v9/modules/core/24-host"
 )
 
@@ -87,39 +84,3 @@ func (p Payload) Validate() error {
 	}
 	return nil
 }
-
-// CommitPacket returns the V2 packet commitment bytes. The commitment consists of:
-// sha256_hash(timeout) + sha256_hash(destinationID) + sha256_hash(packetData) from a given packet.
-// This results in a fixed length preimage.
-// NOTE: A fixed length preimage is ESSENTIAL to prevent relayers from being able
-// to malleate the packet fields and create a commitment hash that matches the original packet.
-func CommitPacket(packet Packet) []byte {
-	buf := sdk.Uint64ToBigEndian(packet.GetTimeoutTimestamp())
-
-	destIDHash := sha256.Sum256([]byte(packet.DestinationId))
-	buf = append(buf, destIDHash[:]...)
-
-	for _, data := range packet.Data {
-		buf = append(buf, hashPacketData(data)...)
-	}
-
-	hash := sha256.Sum256(buf)
-	return hash[:]
-}
-
-// hashPacketData returns the hash of the packet data.
-func hashPacketData(data PacketData) []byte {
-	var buf []byte
-	sourceHash := sha256.Sum256([]byte(data.SourcePort))
-	buf = append(buf, sourceHash[:]...)
-	destHash := sha256.Sum256([]byte(data.DestinationPort))
-	buf = append(buf, destHash[:]...)
-	payloadValueHash := sha256.Sum256(data.Payload.Value)
-	buf = append(buf, payloadValueHash[:]...)
-	payloadEncodingHash := sha256.Sum256([]byte(data.Payload.Encoding))
-	buf = append(buf, payloadEncodingHash[:]...)
-	payloadVersionHash := sha256.Sum256([]byte(data.Payload.Version))
-	buf = append(buf, payloadVersionHash[:]...)
-	hash := sha256.Sum256(buf)
-	return hash[:]
-}