chore: add generic proof verification methods to ClientState interface (

cosmos#1645)

* adding generic proof verification methods to ClientState interface

* adding function boilerplate to solomachine and legacy v100 solomachine

* adding comments for todos

modules/core/02-client/legacy/v100/solomachine.go

@@ -211,6 +211,35 @@ func (cs ClientState) VerifyNextSequenceRecv(
 	panic("legacy solo machine is deprecated!")
 }
 
+// VerifyMembership panics!
+func (cs *ClientState) VerifyMembership(
+	ctx sdk.Context,
+	clientStore sdk.KVStore,
+	cdc codec.BinaryCodec,
+	height exported.Height,
+	delayTimePeriod uint64,
+	delayBlockPeriod uint64,
+	proof []byte,
+	path []byte,
+	value []byte,
+) error {
+	panic("legacy solo machine is deprecated!")
+}
+
+// VerifyNonMembership panics!
+func (cs *ClientState) VerifyNonMembership(
+	ctx sdk.Context,
+	clientStore sdk.KVStore,
+	cdc codec.BinaryCodec,
+	height exported.Height,
+	delayTimePeriod uint64,
+	delayBlockPeriod uint64,
+	proof []byte,
+	path []byte,
+) error {
+	panic("legacy solo machine is deprecated")
+}
+
 // ClientType panics!
 func (ConsensusState) ClientType() string {
 	panic("legacy solo machine is deprecated!")

modules/core/exported/client.go

@@ -98,6 +98,33 @@ type ClientState interface {
 
 	// State verification functions
 
+	// VerifyMembership is a generic proof verification method which verifies a proof of the existence of a value at a given CommitmentPath at the specified height.
+	// The caller is expected to construct the full CommitmentPath from a CommitmentPrefix and a standardized path (as defined in ICS 24).
+	VerifyMembership(
+		ctx sdk.Context,
+		clientStore sdk.KVStore,
+		cdc codec.BinaryCodec,
+		height Height,
+		delayTimePeriod uint64,
+		delayBlockPeriod uint64,
+		proof []byte,
+		path []byte,
+		value []byte,
+	) error
+
+	// VerifyNonMembership is a generic proof verification method which verifies the absense of a given CommitmentPath at a specified height.
+	// The caller is expected to construct the full CommitmentPath from a CommitmentPrefix and a standardized path (as defined in ICS 24).
+	VerifyNonMembership(
+		ctx sdk.Context,
+		clientStore sdk.KVStore,
+		cdc codec.BinaryCodec,
+		height Height,
+		delayTimePeriod uint64,
+		delayBlockPeriod uint64,
+		proof []byte,
+		path []byte,
+	) error
+
 	VerifyClientState(
 		store sdk.KVStore,
 		cdc codec.BinaryCodec,

modules/light-clients/06-solomachine/types/client_state.go

@@ -415,6 +415,39 @@ func (cs *ClientState) VerifyNextSequenceRecv(
 	return nil
 }
 
+// VerifyMembership is a generic proof verification method which verifies a proof of the existence of a value at a given CommitmentPath at the specified height.
+// The caller is expected to construct the full CommitmentPath from a CommitmentPrefix and a standardized path (as defined in ICS 24).
+func (cs *ClientState) VerifyMembership(
+	ctx sdk.Context,
+	clientStore sdk.KVStore,
+	cdc codec.BinaryCodec,
+	height exported.Height,
+	delayTimePeriod uint64,
+	delayBlockPeriod uint64,
+	proof []byte,
+	path []byte,
+	value []byte,
+) error {
+	// TODO: Implement 06-solomachine VerifyMembership
+	return nil
+}
+
+// VerifyNonMembership is a generic proof verification method which verifies the absense of a given CommitmentPath at a specified height.
+// The caller is expected to construct the full CommitmentPath from a CommitmentPrefix and a standardized path (as defined in ICS 24).
+func (cs *ClientState) VerifyNonMembership(
+	ctx sdk.Context,
+	clientStore sdk.KVStore,
+	cdc codec.BinaryCodec,
+	height exported.Height,
+	delayTimePeriod uint64,
+	delayBlockPeriod uint64,
+	proof []byte,
+	path []byte,
+) error {
+	// TODO: Implement 06-solomachine VerifyNonMembership
+	return nil
+}
+
 // produceVerificationArgs perfoms the basic checks on the arguments that are
 // shared between the verification functions and returns the public key of the
 // consensus state, the unmarshalled proof representing the signature and timestamp