core: Export DKGGroupPublicKey and its verify function (#160)

3 files changed, 21 insertions, 18 deletions

diff --git a/core/configuration-chain.go b/core/configuration-chain.go
index 300b080..aca1a84 100644
--- a/core/configuration-chain.go
+++ b/core/configuration-chain.go
@@ -42,7 +42,7 @@ type configurationChain struct {
 	dkg       *dkgProtocol
 	dkgLock   sync.RWMutex
 	dkgSigner map[uint64]*dkgShareSecret
-	gpk       map[uint64]*dkgGroupPublicKey
+	gpk       map[uint64]*DKGGroupPublicKey
 	dkgResult sync.RWMutex
 	tsig      *tsigProtocol
 	tsigReady *sync.Cond
@@ -60,7 +60,7 @@ func newConfigurationChain(
 		recv:      recv,
 		gov:       gov,
 		dkgSigner: make(map[uint64]*dkgShareSecret),
-		gpk:       make(map[uint64]*dkgGroupPublicKey),
+		gpk:       make(map[uint64]*DKGGroupPublicKey),
 		tsigReady: sync.NewCond(&sync.Mutex{}),
 	}
 }
@@ -123,7 +123,7 @@ func (cc *configurationChain) runDKG(round uint64) error {
 	cc.dkgLock.Unlock()
 	<-ticker.Tick()
 	cc.dkgLock.Lock()
-	gpk, err := newDKGGroupPublicKey(round,
+	gpk, err := NewDKGGroupPublicKey(round,
 		cc.gov.DKGMasterPublicKeys(round),
 		cc.gov.DKGComplaints(round),
 		cc.dkg.threshold)
@@ -170,7 +170,7 @@ func (cc *configurationChain) preparePartialSignature(
 func (cc *configurationChain) runTSig(
 	round uint64, hash common.Hash, psigType types.DKGPartialSignatureType) (
 	crypto.Signature, error) {
-	gpk, exist := func() (*dkgGroupPublicKey, bool) {
+	gpk, exist := func() (*DKGGroupPublicKey, bool) {
 		cc.dkgResult.RLock()
 		defer cc.dkgResult.RUnlock()
 		gpk, exist := cc.gpk[round]
diff --git a/core/dkg-tsig-protocol.go b/core/dkg-tsig-protocol.go
index 2bdb4e9..2bb4c52 100644
--- a/core/dkg-tsig-protocol.go
+++ b/core/dkg-tsig-protocol.go
@@ -81,7 +81,8 @@ type dkgShareSecret struct {
 	privateKey *dkg.PrivateKey
 }
 
-type dkgGroupPublicKey struct {
+// DKGGroupPublicKey is the result of DKG protocol.
+type DKGGroupPublicKey struct {
 	round          uint64
 	qualifyIDs     dkg.IDs
 	qualifyNodeIDs map[types.NodeID]struct{}
@@ -92,7 +93,7 @@ type dkgGroupPublicKey struct {
 }
 
 type tsigProtocol struct {
-	groupPublicKey *dkgGroupPublicKey
+	groupPublicKey *DKGGroupPublicKey
 	hash           common.Hash
 	psigType       types.DKGPartialSignatureType
 	sigs           map[dkg.ID]dkg.PartialSignature
@@ -311,11 +312,12 @@ func (ss *dkgShareSecret) sign(hash common.Hash) dkg.PartialSignature {
 	return dkg.PartialSignature(sig)
 }
 
-func newDKGGroupPublicKey(
+// NewDKGGroupPublicKey creats a DKGGroupPublicKey instance.
+func NewDKGGroupPublicKey(
 	round uint64,
 	mpks []*types.DKGMasterPublicKey, complaints []*types.DKGComplaint,
 	threshold int) (
-	*dkgGroupPublicKey, error) {
+	*DKGGroupPublicKey, error) {
 	// Calculate qualify members.
 	disqualifyIDs := map[types.NodeID]struct{}{}
 	complaintsByID := map[types.NodeID]int{}
@@ -369,7 +371,7 @@ func newDKGGroupPublicKey(
 		pubShares = append(pubShares, &mpkMap[id].PublicKeyShares)
 	}
 	groupPK := dkg.RecoverGroupPublicKey(pubShares)
-	return &dkgGroupPublicKey{
+	return &DKGGroupPublicKey{
 		round:          round,
 		qualifyIDs:     qualifyIDs,
 		qualifyNodeIDs: qualifyNodeIDs,
@@ -380,13 +382,14 @@ func newDKGGroupPublicKey(
 	}, nil
 }
 
-func (gpk *dkgGroupPublicKey) verifySignature(
+// VerifySignature verifies if the signature is correct.
+func (gpk *DKGGroupPublicKey) VerifySignature(
 	hash common.Hash, sig crypto.Signature) bool {
 	return gpk.groupPublicKey.VerifySignature(hash, sig)
 }
 
 func newTSigProtocol(
-	gpk *dkgGroupPublicKey,
+	gpk *DKGGroupPublicKey,
 	hash common.Hash,
 	psigType types.DKGPartialSignatureType) *tsigProtocol {
 	return &tsigProtocol{
diff --git a/core/dkg-tsig-protocol_test.go b/core/dkg-tsig-protocol_test.go
index 6273e53..1e8cac4 100644
--- a/core/dkg-tsig-protocol_test.go
+++ b/core/dkg-tsig-protocol_test.go
@@ -181,7 +181,7 @@ func (s *DKGTSIGProtocolTestSuite) TestDKGTSIGProtocol() {
 	}
 
 	// DKG is fininished.
-	gpk, err := newDKGGroupPublicKey(round,
+	gpk, err := NewDKGGroupPublicKey(round,
 		gov.DKGMasterPublicKeys(round), gov.DKGComplaints(round),
 		k,
 	)
@@ -230,7 +230,7 @@ func (s *DKGTSIGProtocolTestSuite) TestDKGTSIGProtocol() {
 
 	sig, err := tsig.signature()
 	s.Require().NoError(err)
-	s.True(gpk.verifySignature(msgHash, sig))
+	s.True(gpk.VerifySignature(msgHash, sig))
 }
 
 func (s *DKGTSIGProtocolTestSuite) TestNackComplaint() {
@@ -477,7 +477,7 @@ func (s *DKGTSIGProtocolTestSuite) TestQualifyIDs() {
 		s.Require().True(complaints[i].IsNack())
 	}
 
-	gpk, err := newDKGGroupPublicKey(round,
+	gpk, err := NewDKGGroupPublicKey(round,
 		gov.DKGMasterPublicKeys(round), complaints,
 		k,
 	)
@@ -487,7 +487,7 @@ func (s *DKGTSIGProtocolTestSuite) TestQualifyIDs() {
 		s.NotEqual(id, byzantineID)
 	}
 
-	gpk2, err := newDKGGroupPublicKey(round,
+	gpk2, err := NewDKGGroupPublicKey(round,
 		gov.DKGMasterPublicKeys(round), complaints[:k],
 		k,
 	)
@@ -497,7 +497,7 @@ func (s *DKGTSIGProtocolTestSuite) TestQualifyIDs() {
 	// Test for complaint.
 	complaints[0].PrivateShare.Signature = crypto.Signature{Signature: []byte{0}}
 	s.Require().False(complaints[0].IsNack())
-	gpk3, err := newDKGGroupPublicKey(round,
+	gpk3, err := NewDKGGroupPublicKey(round,
 		gov.DKGMasterPublicKeys(round), complaints[:1],
 		k,
 	)
@@ -552,7 +552,7 @@ func (s *DKGTSIGProtocolTestSuite) TestPartialSignature() {
 	}
 
 	// DKG is fininished.
-	gpk, err := newDKGGroupPublicKey(round,
+	gpk, err := NewDKGGroupPublicKey(round,
 		gov.DKGMasterPublicKeys(round), gov.DKGComplaints(round),
 		k,
 	)
@@ -613,7 +613,7 @@ func (s *DKGTSIGProtocolTestSuite) TestPartialSignature() {
 
 	sig, err := tsig.signature()
 	s.Require().NoError(err)
-	s.True(gpk.verifySignature(msgHash, sig))
+	s.True(gpk.VerifySignature(msgHash, sig))
 }
 
 func TestDKGTSIGProtocol(t *testing.T) {