[3/?] - lnwire: add new TLV record types + messages for taproot chans

channeldb/graph.go

@@ -2726,7 +2726,7 @@ func (l *LightningNode) NodeAnnouncement(signed bool) (*lnwire.NodeAnnouncement,
 		return nodeAnn, nil
 	}
 
-	sig, err := lnwire.NewSigFromRawSignature(l.AuthSigBytes)
+	sig, err := lnwire.NewSigFromECDSARawSignature(l.AuthSigBytes)
 	if err != nil {
 		return nil, err
 	}

discovery/gossiper.go

@@ -2201,25 +2201,25 @@ func (d *AuthenticatedGossiper) updateChannel(info *channeldb.ChannelEdgeInfo,
 			BitcoinKey2:     info.BitcoinKey2Bytes,
 			ExtraOpaqueData: edge.ExtraOpaqueData,
 		}
-		chanAnn.NodeSig1, err = lnwire.NewSigFromRawSignature(
+		chanAnn.NodeSig1, err = lnwire.NewSigFromECDSARawSignature(
 			info.AuthProof.NodeSig1Bytes,
 		)
 		if err != nil {
 			return nil, nil, err
 		}
-		chanAnn.NodeSig2, err = lnwire.NewSigFromRawSignature(
+		chanAnn.NodeSig2, err = lnwire.NewSigFromECDSARawSignature(
 			info.AuthProof.NodeSig2Bytes,
 		)
 		if err != nil {
 			return nil, nil, err
 		}
-		chanAnn.BitcoinSig1, err = lnwire.NewSigFromRawSignature(
+		chanAnn.BitcoinSig1, err = lnwire.NewSigFromECDSARawSignature(
 			info.AuthProof.BitcoinSig1Bytes,
 		)
 		if err != nil {
 			return nil, nil, err
 		}
-		chanAnn.BitcoinSig2, err = lnwire.NewSigFromRawSignature(
+		chanAnn.BitcoinSig2, err = lnwire.NewSigFromECDSARawSignature(
 			info.AuthProof.BitcoinSig2Bytes,
 		)
 		if err != nil {

docs/release-notes/release-notes-0.17.0.md

@@ -0,0 +1,10 @@
+# Release Notes
+
+## BOLT Specs
+
+* The `lnwire` library is now able to [parse messages for the new experimental
+  taproot channels spec proposal](https://github.com/lightningnetwork/lnd/pull/7331).
+
+# Contributors (Alphabetical Order)
+
+* Olaoluwa Osuntokun

htlcswitch/link_test.go

@@ -5374,9 +5374,15 @@ func TestChannelLinkFail(t *testing.T) {
 
 				// Flip a bit on the signature, rendering it
 				// invalid.
-				sig[19] ^= 1
+				sigCopy := sig.Copy()
+				copyBytes := sigCopy.RawBytes()
+				copyBytes[19] ^= 1
+				modifiedSig, err := lnwire.NewSigFromWireECDSA(
+					copyBytes,
+				)
+				require.NoError(t, err)
 				commitSig := &lnwire.CommitSig{
-					CommitSig: sig,
+					CommitSig: modifiedSig,
 					HtlcSigs:  htlcSigs,
 				}
 

lnrpc/routerrpc/router_backend.go

@@ -1283,7 +1283,7 @@ func marshallChannelUpdate(update *lnwire.ChannelUpdate) *lnrpc.ChannelUpdate {
 	}
 
 	return &lnrpc.ChannelUpdate{
-		Signature:       update.Signature[:],
+		Signature:       update.Signature.RawBytes(),
 		ChainHash:       update.ChainHash[:],
 		ChanId:          update.ShortChannelID.ToUint64(),
 		Timestamp:       update.Timestamp,

lnrpc/signrpc/signer_server.go

@@ -713,7 +713,7 @@ func (s *Server) VerifyMessage(_ context.Context,
 	}
 
 	// The signature must be fixed-size LN wire format encoded.
-	wireSig, err := lnwire.NewSigFromRawSignature(in.Signature)
+	wireSig, err := lnwire.NewSigFromECDSARawSignature(in.Signature)
 	if err != nil {
 		return nil, fmt.Errorf("failed to decode signature: %v", err)
 	}

lnwallet/chancloser/chancloser.go

@@ -785,16 +785,18 @@ func (c *ChanCloser) proposeCloseSigned(fee btcutil.Amount) (*lnwire.ClosingSign
 		return nil, err
 	}
 
-	// We'll note our last signature and proposed fee so when the remote party
-	// responds we'll be able to decide if we've agreed on fees or not.
+	// We'll note our last signature and proposed fee so when the remote
+	// party responds we'll be able to decide if we've agreed on fees or
+	// not.
 	c.lastFeeProposal = fee
+
 	parsedSig, err := lnwire.NewSigFromSignature(rawSig)
 	if err != nil {
 		return nil, err
 	}
 
-	chancloserLog.Infof("ChannelPoint(%v): proposing fee of %v sat to close "+
-		"chan", c.chanPoint, int64(fee))
+	chancloserLog.Infof("ChannelPoint(%v): proposing fee of %v sat to "+
+		"close chan", c.chanPoint, int64(fee))
 
 	// We'll assemble a ClosingSigned message using this information and return
 	// it to the caller so we can kick off the final stage of the channel

lnwallet/channel.go

@@ -320,7 +320,7 @@ type PaymentDescriptor struct {
 	// local node. This signature is generated by the remote node and
 	// stored by the local node in the case that local node needs to
 	// broadcast their commitment transaction.
-	sig *ecdsa.Signature
+	sig input.Signature
 
 	// addCommitHeight[Remote|Local] encodes the height of the commitment
 	// which included this HTLC on either the remote or local commitment
@@ -4333,7 +4333,7 @@ func genHtlcSigValidationJobs(localCommitmentView *commitment,
 		var (
 			htlcIndex uint64
 			sigHash   func() ([]byte, error)
-			sig       *ecdsa.Signature
+			sig       input.Signature
 			err       error
 		)
 

lnwallet/channel_test.go

@@ -5331,7 +5331,11 @@ func TestInvalidCommitSigError(t *testing.T) {
 
 	// Before the signature gets to Bob, we'll mutate it, such that the
 	// signature is now actually invalid.
-	aliceSig[0] ^= 88
+	aliceSigCopy := aliceSig.Copy()
+	aliceSigCopyBytes := aliceSigCopy.RawBytes()
+	aliceSigCopyBytes[0] ^= 88
+	aliceSig, err = lnwire.NewSigFromWireECDSA(aliceSigCopyBytes)
+	require.NoError(t, err)
 
 	// Bob should reject this new state, and return the proper error.
 	err = bobChannel.ReceiveNewCommitment(aliceSig, aliceHtlcSigs)

lnwallet/rpcwallet/rpcwallet.go

@@ -453,11 +453,20 @@ func (r *RPCKeyRing) SignMessage(keyLoc keychain.KeyLocator,
 			"signer instance: %v", err)
 	}
 
-	wireSig, err := lnwire.NewSigFromRawSignature(resp.Signature)
+	wireSig, err := lnwire.NewSigFromECDSARawSignature(resp.Signature)
 	if err != nil {
-		return nil, fmt.Errorf("error parsing raw signature: %v", err)
+		return nil, fmt.Errorf("unable to create sig: %w", err)
 	}
-	return wireSig.ToSignature()
+	sig, err := wireSig.ToSignature()
+	if err != nil {
+		return nil, fmt.Errorf("unable to parse sig: %w", err)
+	}
+	ecdsaSig, ok := sig.(*ecdsa.Signature)
+	if !ok {
+		return nil, fmt.Errorf("unexpected signature type: %T", sig)
+	}
+
+	return ecdsaSig, nil
 }
 
 // SignMessageCompact signs the given message, single or double SHA256 hashing

lnwallet/sigpool.go

@@ -5,7 +5,6 @@ import (
 	"sync"
 
 	"github.com/btcsuite/btcd/btcec/v2"
-	"github.com/btcsuite/btcd/btcec/v2/ecdsa"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/lnwire"
@@ -36,7 +35,7 @@ type VerifyJob struct {
 
 	// Sig is the raw signature generated using the above public key.  This
 	// is the signature to be verified.
-	Sig *ecdsa.Signature
+	Sig input.Signature
 
 	// SigHash is a function closure generates the sighashes that the
 	// passed signature is known to have signed.

lnwire/accept_channel.go

@@ -105,6 +105,13 @@ type AcceptChannel struct {
 	// type.
 	LeaseExpiry *LeaseExpiry
 
+	// LocalNonce is an optional field that transmits the
+	// local/verification nonce for a party. This nonce will be used to
+	// verify the very first commitment transaction signature.
+	// This will only be populated if the simple taproot channels type was
+	// negotiated.
+	LocalNonce *Musig2Nonce
+
 	// ExtraData is the set of data that was appended to this message to
 	// fill out the full maximum transport message size. These fields can
 	// be used to specify optional data such as custom TLV fields.
@@ -134,6 +141,9 @@ func (a *AcceptChannel) Encode(w *bytes.Buffer, pver uint32) error {
 	if a.LeaseExpiry != nil {
 		recordProducers = append(recordProducers, a.LeaseExpiry)
 	}
+	if a.LocalNonce != nil {
+		recordProducers = append(recordProducers, a.LocalNonce)
+	}
 	err := EncodeMessageExtraData(&a.ExtraData, recordProducers...)
 	if err != nil {
 		return err
@@ -238,9 +248,11 @@ func (a *AcceptChannel) Decode(r io.Reader, pver uint32) error {
 	var (
 		chanType    ChannelType
 		leaseExpiry LeaseExpiry
+		localNonce  Musig2Nonce
 	)
 	typeMap, err := tlvRecords.ExtractRecords(
 		&a.UpfrontShutdownScript, &chanType, &leaseExpiry,
+		&localNonce,
 	)
 	if err != nil {
 		return err
@@ -253,6 +265,9 @@ func (a *AcceptChannel) Decode(r io.Reader, pver uint32) error {
 	if val, ok := typeMap[LeaseExpiryRecordType]; ok && val == nil {
 		a.LeaseExpiry = &leaseExpiry
 	}
+	if val, ok := typeMap[NonceRecordType]; ok && val == nil {
+		a.LocalNonce = &localNonce
+	}
 
 	a.ExtraData = tlvRecords
 

lnwire/channel_reestablish.go

@@ -5,6 +5,7 @@ import (
 	"io"
 
 	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/lightningnetwork/lnd/tlv"
 )
 
 // ChannelReestablish is a message sent between peers that have an existing
@@ -62,6 +63,13 @@ type ChannelReestablish struct {
 	// current un-revoked commitment transaction of the sending party.
 	LocalUnrevokedCommitPoint *btcec.PublicKey
 
+	// LocalNonce is an optional field that stores a local musig2 nonce.
+	// This will only be populated if the simple taproot channels type was
+	// negotiated.
+	//
+	// TODO(roasbeef): rename to verification nonce
+	LocalNonce *Musig2Nonce
+
 	// ExtraData is the set of data that was appended to this message to
 	// fill out the full maximum transport message size. These fields can
 	// be used to specify optional data such as custom TLV fields.
@@ -108,6 +116,16 @@ func (a *ChannelReestablish) Encode(w *bytes.Buffer, pver uint32) error {
 	if err := WritePublicKey(w, a.LocalUnrevokedCommitPoint); err != nil {
 		return err
 	}
+
+	recordProducers := make([]tlv.RecordProducer, 0, 1)
+	if a.LocalNonce != nil {
+		recordProducers = append(recordProducers, a.LocalNonce)
+	}
+	err := EncodeMessageExtraData(&a.ExtraData, recordProducers...)
+	if err != nil {
+		return err
+	}
+
 	return WriteBytes(w, a.ExtraData)
 }
 
@@ -156,7 +174,28 @@ func (a *ChannelReestablish) Decode(r io.Reader, pver uint32) error {
 		return err
 	}
 
-	return a.ExtraData.Decode(r)
+	var tlvRecords ExtraOpaqueData
+	if err := ReadElements(r, &tlvRecords); err != nil {
+		return err
+	}
+
+	var localNonce Musig2Nonce
+	typeMap, err := tlvRecords.ExtractRecords(
+		&localNonce,
+	)
+	if err != nil {
+		return err
+	}
+
+	if val, ok := typeMap[NonceRecordType]; ok && val == nil {
+		a.LocalNonce = &localNonce
+	}
+
+	if len(tlvRecords) != 0 {
+		a.ExtraData = tlvRecords
+	}
+
+	return nil
 }
 
 // MsgType returns the integer uniquely identifying this message type on the

lnwire/closing_signed.go

@@ -5,6 +5,7 @@ import (
 	"io"
 
 	"github.com/btcsuite/btcd/btcutil"
+	"github.com/lightningnetwork/lnd/tlv"
 )
 
 // ClosingSigned is sent by both parties to a channel once the channel is clear
@@ -29,6 +30,14 @@ type ClosingSigned struct {
 	// Signature is for the proposed channel close transaction.
 	Signature Sig
 
+	// PartialSig is used to transmit a musig2 extended partial signature
+	// that signs the latest fee offer. The nonce isn't sent along side, as
+	// that has already been sent in the initial shutdown message.
+	//
+	// NOTE: This field is only populated if a musig2 taproot channel is
+	// being signed for. In this case, the above Sig type MUST be blank.
+	PartialSig *PartialSig
+
 	// ExtraData is the set of data that was appended to this message to
 	// fill out the full maximum transport message size. These fields can
 	// be used to specify optional data such as custom TLV fields.
@@ -55,16 +64,52 @@ var _ Message = (*ClosingSigned)(nil)
 //
 // This is part of the lnwire.Message interface.
 func (c *ClosingSigned) Decode(r io.Reader, pver uint32) error {
-	return ReadElements(
-		r, &c.ChannelID, &c.FeeSatoshis, &c.Signature, &c.ExtraData,
+	err := ReadElements(
+		r, &c.ChannelID, &c.FeeSatoshis, &c.Signature,
+	)
+	if err != nil {
+		return err
+	}
+
+	var tlvRecords ExtraOpaqueData
+	if err := ReadElements(r, &tlvRecords); err != nil {
+		return err
+	}
+
+	var (
+		partialSig PartialSig
 	)
+	typeMap, err := tlvRecords.ExtractRecords(&partialSig)
+	if err != nil {
+		return err
+	}
+
+	// Set the corresponding TLV types if they were included in the stream.
+	if val, ok := typeMap[PartialSigRecordType]; ok && val == nil {
+		c.PartialSig = &partialSig
+	}
+
+	if len(tlvRecords) != 0 {
+		c.ExtraData = tlvRecords
+	}
+
+	return nil
 }
 
 // Encode serializes the target ClosingSigned into the passed io.Writer
 // observing the protocol version specified.
 //
 // This is part of the lnwire.Message interface.
 func (c *ClosingSigned) Encode(w *bytes.Buffer, pver uint32) error {
+	recordProducers := make([]tlv.RecordProducer, 0, 1)
+	if c.PartialSig != nil {
+		recordProducers = append(recordProducers, c.PartialSig)
+	}
+	err := EncodeMessageExtraData(&c.ExtraData, recordProducers...)
+	if err != nil {
+		return err
+	}
+
 	if err := WriteChannelID(w, c.ChannelID); err != nil {
 		return err
 	}