feat(callbacks): adr8 implementation

modules/apps/27-interchain-accounts/controller/ibc_middleware.go

@@ -17,7 +17,10 @@ import (
 	ibcexported "github.com/cosmos/ibc-go/v7/modules/core/exported"
 )
 
-var _ porttypes.Middleware = (*IBCMiddleware)(nil)
+var (
+	_ porttypes.Middleware            = (*IBCMiddleware)(nil)
+	_ porttypes.PacketDataUnmarshaler = (*IBCMiddleware)(nil)
+)
 
 // IBCMiddleware implements the ICS26 callbacks for the fee middleware given the
 // ICA controller keeper and the underlying application.
@@ -253,3 +256,15 @@ func (im IBCMiddleware) WriteAcknowledgement(
 func (im IBCMiddleware) GetAppVersion(ctx sdk.Context, portID, channelID string) (string, bool) {
 	return im.keeper.GetAppVersion(ctx, portID, channelID)
 }
+
+// UnmarshalPacketData attempts to unmarshal the provided packet data bytes
+// into an InterchainAccountPacketData. This function implements the optional
+// PacketDataUnmarshaler interface required for ADR 008 support.
+func (im IBCMiddleware) UnmarshalPacketData(bz []byte) (interface{}, error) {
+	var packetData icatypes.InterchainAccountPacketData
+	if err := icatypes.ModuleCdc.UnmarshalJSON(bz, &packetData); err != nil {
+		return nil, err
+	}
+
+	return packetData, nil
+}

modules/apps/27-interchain-accounts/controller/ibc_middleware_test.go

@@ -918,3 +918,20 @@ func (suite *InterchainAccountsTestSuite) TestClosedChannelReopensWithMsgServer(
 	err = path.EndpointB.ChanOpenConfirm()
 	suite.Require().NoError(err)
 }
+
+func (suite *InterchainAccountsTestSuite) TestUnmarshalPacketData() {
+	expPacketData := icatypes.InterchainAccountPacketData{
+		Type: icatypes.EXECUTE_TX,
+		Data: []byte("data"),
+		Memo: `{"callback": {"src_callback_address": "testAddr"}}`,
+	}
+
+	packetData, err := controller.IBCMiddleware{}.UnmarshalPacketData(expPacketData.GetBytes())
+	suite.Require().NoError(err)
+	suite.Require().Equal(expPacketData, packetData)
+
+	invalidPacketData := []byte("invalid packet data")
+	packetData, err = controller.IBCMiddleware{}.UnmarshalPacketData(invalidPacketData)
+	suite.Require().Error(err)
+	suite.Require().Nil(packetData)
+}

modules/apps/27-interchain-accounts/host/ibc_module.go

@@ -12,10 +12,16 @@ import (
 	"github.com/cosmos/ibc-go/v7/modules/apps/27-interchain-accounts/host/types"
 	icatypes "github.com/cosmos/ibc-go/v7/modules/apps/27-interchain-accounts/types"
 	channeltypes "github.com/cosmos/ibc-go/v7/modules/core/04-channel/types"
+	porttypes "github.com/cosmos/ibc-go/v7/modules/core/05-port/types"
 	ibcerrors "github.com/cosmos/ibc-go/v7/modules/core/errors"
 	ibcexported "github.com/cosmos/ibc-go/v7/modules/core/exported"
 )
 
+var (
+	_ porttypes.IBCModule             = &IBCModule{}
+	_ porttypes.PacketDataUnmarshaler = &IBCModule{}
+)
+
 // IBCModule implements the ICS26 interface for interchain accounts host chains
 type IBCModule struct {
 	keeper keeper.Keeper
@@ -149,3 +155,15 @@ func (im IBCModule) OnTimeoutPacket(
 ) error {
 	return errorsmod.Wrap(icatypes.ErrInvalidChannelFlow, "cannot cause a packet timeout on a host channel end, a host chain does not send a packet over the channel")
 }
+
+// UnmarshalPacketData attempts to unmarshal the provided packet data bytes
+// into an InterchainAccountPacketData. This function implements the optional
+// PacketDataUnmarshaler interface required for ADR 008 support.
+func (im IBCModule) UnmarshalPacketData(bz []byte) (interface{}, error) {
+	var packetData icatypes.InterchainAccountPacketData
+	if err := icatypes.ModuleCdc.UnmarshalJSON(bz, &packetData); err != nil {
+		return nil, err
+	}
+
+	return packetData, nil
+}

modules/apps/27-interchain-accounts/host/ibc_module_test.go

@@ -14,6 +14,7 @@ import (
 	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
 
 	capabilitytypes "github.com/cosmos/ibc-go/modules/capability/types"
+	icahost "github.com/cosmos/ibc-go/v7/modules/apps/27-interchain-accounts/host"
 	"github.com/cosmos/ibc-go/v7/modules/apps/27-interchain-accounts/host/types"
 	icatypes "github.com/cosmos/ibc-go/v7/modules/apps/27-interchain-accounts/types"
 	feetypes "github.com/cosmos/ibc-go/v7/modules/apps/29-fee/types"
@@ -708,6 +709,23 @@ func (suite *InterchainAccountsTestSuite) TestControlAccountAfterChannelClose()
 	suite.assertBalance(icaAddr, expBalAfterSecondSend)
 }
 
+func (suite *InterchainAccountsTestSuite) TestUnmarshalPacketData() {
+	expPacketData := icatypes.InterchainAccountPacketData{
+		Type: icatypes.EXECUTE_TX,
+		Data: []byte("data"),
+		Memo: `{"callback": {"src_callback_address": "testAddr"}}`,
+	}
+
+	packetData, err := icahost.IBCModule{}.UnmarshalPacketData(expPacketData.GetBytes())
+	suite.Require().NoError(err)
+	suite.Require().Equal(expPacketData, packetData)
+
+	invalidPacketData := []byte("invalid packet data")
+	packetData, err = icahost.IBCModule{}.UnmarshalPacketData(invalidPacketData)
+	suite.Require().Error(err)
+	suite.Require().Nil(packetData)
+}
+
 // assertBalance asserts that the provided address has exactly the expected balance.
 // CONTRACT: the expected balance must only contain one coin denom.
 func (suite *InterchainAccountsTestSuite) assertBalance(addr sdk.AccAddress, expBalance sdk.Coins) {

modules/apps/27-interchain-accounts/types/packet.go

@@ -1,12 +1,16 @@
 package types
 
 import (
+	"encoding/base64"
+	"encoding/json"
 	"time"
 
 	errorsmod "cosmossdk.io/errors"
 
 	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	"github.com/cosmos/ibc-go/v7/modules/core/exported"
 )
 
 // MaxMemoCharLength defines the maximum length for the InterchainAccountPacketData memo field
@@ -25,6 +29,8 @@ var (
 	DefaultRelativePacketTimeoutTimestamp = uint64((time.Duration(10) * time.Minute).Nanoseconds())
 )
 
+var _ exported.CallbackPacketData = (*InterchainAccountPacketData)(nil)
+
 // ValidateBasic performs basic validation of the interchain account packet data.
 // The memo may be empty.
 func (iapd InterchainAccountPacketData) ValidateBasic() error {
@@ -48,6 +54,115 @@ func (iapd InterchainAccountPacketData) GetBytes() []byte {
 	return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(&iapd))
 }
 
+/*
+
+ADR-8 CallbackPacketData implementation
+
+InterchainAccountPacketData implements CallbackPacketData interface. This will allow middlewares targeting specific VMs
+to retrieve the desired callback address for the ICA packet on the source chain. Destination callback addresses are not
+supported for ICS 27.
+
+The Memo is used to set the desired callback addresses.
+
+The Memo format is defined like so:
+
+```json
+{
+	// ... other memo fields we don't care about
+	"callback": {
+		"src_callback_address": {contractAddrOnSourceChain},
+
+		// optional fields
+		"callback_msg": {base64StringForCallback},
+	}
+}
+```
+
+*/
+
+// GetSourceCallbackAddress returns the source callback address provided in the packet data memo.
+// If no callback address is specified, an empty string is returned.
+//
+// The memo is expected to specify the callback address in the following format:
+// { "callback": { "src_callback_address": {contractAddrOnSourceChain}}
+//
+// ADR-8 middleware should callback on the returned address if it is a PacketActor
+// (i.e. smart contract that accepts IBC callbacks).
+func (iapd InterchainAccountPacketData) GetSourceCallbackAddress() string {
+	callbackData := iapd.GetCallbackData()
+	if callbackData == nil {
+		return ""
+	}
+
+	callbackAddr, ok := callbackData["src_callback_address"].(string)
+	if !ok {
+		return ""
+	}
+
+	return callbackAddr
+}
+
+// GetDestCallbackAddress returns an empty string. Destination callback addresses
+// are not supported for ICS 27. This feature is natively supported by
+// interchain accounts host submodule transaction execution.
+func (iapd InterchainAccountPacketData) GetDestCallbackAddress() string {
+	return ""
+}
+
+// GetUserDefinedCustomMessage returns the custom message provided in the packet data memo.
+// Custom message is expected to be base64 encoded.
+//
+// The memo is expected to specify the callback address in the following format:
+// { "callback": { ... , "callback_msg": {base64StringForCallback} }
+//
+// If no custom message is specified, nil is returned.
+func (iapd InterchainAccountPacketData) GetUserDefinedCustomMessage() []byte {
+	callbackData := iapd.GetCallbackData()
+	if callbackData == nil {
+		return nil
+	}
+
+	callbackMsg, ok := callbackData["callback_msg"].(string)
+	if !ok {
+		return nil
+	}
+
+	// base64 decode the callback message
+	base64DecodedMsg, err := base64.StdEncoding.DecodeString(callbackMsg)
+	if err != nil {
+		return nil
+	}
+
+	return base64DecodedMsg
+}
+
+// UserDefinedGasLimit returns 0 (no-op). The gas limit of the executing
+// transaction will be used.
+func (iapd InterchainAccountPacketData) UserDefinedGasLimit() uint64 {
+	return 0
+}
+
+// getCallbackData returns the memo as `map[string]interface{}` so that it can be
+// interpreted as a json object with keys.
+func (iapd InterchainAccountPacketData) GetCallbackData() map[string]interface{} {
+	if len(iapd.Memo) == 0 {
+		return nil
+	}
+
+	jsonObject := make(map[string]interface{})
+	err := json.Unmarshal([]byte(iapd.Memo), &jsonObject)
+	if err != nil {
+		return nil
+	}
+
+	callbackData, ok := jsonObject["callback"].(map[string]interface{})
+	if !ok {
+		return nil
+	}
+
+	return callbackData
+}
+
 // GetBytes returns the JSON marshalled interchain account CosmosTx.
 func (ct CosmosTx) GetBytes() []byte {
 	return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(&ct))

modules/apps/27-interchain-accounts/types/packet_test.go

@@ -1,6 +1,8 @@
 package types_test
 
 import (
+	"fmt"
+
 	"github.com/cosmos/ibc-go/v7/modules/apps/27-interchain-accounts/types"
 )
 
@@ -82,3 +84,123 @@ func (suite *TypesTestSuite) TestValidateBasic() {
 		})
 	}
 }
+
+func (suite *TypesTestSuite) TestGetSourceCallbackAddress() {
+	const expSrcCbAddr = "srcCbAddr"
+
+	testCases := []struct {
+		name       string
+		packetData types.InterchainAccountPacketData
+		expPass    bool
+	}{
+		{
+			"memo is empty",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: "",
+			},
+			false,
+		},
+		{
+			"memo is not json string",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: "memo",
+			},
+			false,
+		},
+		{
+			"memo does not have callbacks in json struct",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: `{"Key": 10}`,
+			},
+			false,
+		},
+		{
+			"memo has callbacks in json struct but does not have src_callback_address key",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: `{"callback": {"Key": 10}}`,
+			},
+			false,
+		},
+		{
+			"memo has callbacks in json struct but does not have string value for src_callback_address key",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: `{"callback": {"src_callback_address": 10}}`,
+			},
+			false,
+		},
+		{
+			"memo has callbacks in json struct and properly formatted src_callback_address",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: fmt.Sprintf(`{"callback": {"src_callback_address": "%s"}}`, expSrcCbAddr),
+			},
+			true,
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		suite.Run(tc.name, func() {
+			srcCbAddr := tc.packetData.GetSourceCallbackAddress()
+
+			if tc.expPass {
+				suite.Require().Equal(expSrcCbAddr, srcCbAddr)
+			} else {
+				suite.Require().Equal("", srcCbAddr)
+			}
+		})
+	}
+}
+
+func (suite *TypesTestSuite) TestGetDestCallbackAddress() {
+	testCases := []struct {
+		name       string
+		packetData types.InterchainAccountPacketData
+	}{
+		{
+			"memo is empty",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: "",
+			},
+		},
+		{
+			"memo has dest callback address specified in json struct",
+			types.InterchainAccountPacketData{
+				Type: types.EXECUTE_TX,
+				Data: []byte("data"),
+				Memo: `{"callback": {"dest_callback_address": "testAddress"}}`,
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		suite.Run(tc.name, func() {
+			destCbAddr := tc.packetData.GetDestCallbackAddress()
+			suite.Require().Equal("", destCbAddr)
+		})
+	}
+}
+
+func (suite *TypesTestSuite) TestUserDefinedGasLimit() {
+	packetData := types.InterchainAccountPacketData{
+		Type: types.EXECUTE_TX,
+		Data: []byte("data"),
+		Memo: `{"callback": {"user_defined_gas_limit": 100}}`,
+	}
+
+	suite.Require().Equal(uint64(0), packetData.UserDefinedGasLimit(), "user defined gas limit does not return 0")
+}