[WIP] multi: use ChannelAnnouncement2 to advertise Taproot Channels

channeldb/announcement_nonces.go

@@ -0,0 +1,132 @@
+package channeldb
+
+import (
+	"fmt"
+
+	"github.com/btcsuite/btcd/btcec/v2/schnorr/musig2"
+	"github.com/lightningnetwork/lnd/kvdb"
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+var announcementNoncesBucket = []byte("announcement-nonces")
+
+func (c *ChannelStateDB) SaveAnnouncementNonces(chanID lnwire.ChannelID, node,
+	btc [musig2.PubNonceSize]byte) error {
+
+	chanIDCopy := make([]byte, 32)
+	copy(chanIDCopy, chanID[:])
+
+	scratch := make([]byte, musig2.PubNonceSize*2)
+	copy(scratch[:musig2.PubNonceSize], node[:])
+	copy(scratch[musig2.PubNonceSize:], btc[:])
+
+	return kvdb.Update(c.backend, func(tx kvdb.RwTx) error {
+		bucket, err := tx.CreateTopLevelBucket(
+			announcementNoncesBucket,
+		)
+		if err != nil {
+			return err
+		}
+
+		return bucket.Put(chanIDCopy, scratch)
+	}, func() {})
+}
+
+type AnnouncementNonces struct {
+	Btc  [musig2.PubNonceSize]byte
+	Node [musig2.PubNonceSize]byte
+}
+
+func (c *ChannelStateDB) GetAllAnnouncementNonces() (map[lnwire.ChannelID]*AnnouncementNonces, error) {
+
+	m := make(map[lnwire.ChannelID]*AnnouncementNonces)
+	err := kvdb.View(c.backend, func(tx kvdb.RTx) error {
+		bucket := tx.ReadBucket(announcementNoncesBucket)
+		if bucket == nil {
+			return nil
+		}
+
+		return bucket.ForEach(func(k, v []byte) error {
+			if len(k) != 32 {
+				return fmt.Errorf("invalid chan ID key")
+			}
+			if len(v) != musig2.PubNonceSize*2 {
+				return fmt.Errorf("wrong number of bytes")
+			}
+
+			var chanID lnwire.ChannelID
+			copy(chanID[:], k)
+
+			var btc, node [musig2.PubNonceSize]byte
+
+			copy(btc[:], v[:musig2.PubNonceSize])
+			copy(node[:], v[musig2.PubNonceSize:])
+
+			m[chanID] = &AnnouncementNonces{
+				Btc:  btc,
+				Node: node,
+			}
+
+			return nil
+		})
+	}, func() {
+		m = make(map[lnwire.ChannelID]*AnnouncementNonces)
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return m, nil
+}
+
+func (c *ChannelStateDB) GetAnnouncementNonces(chanID lnwire.ChannelID) (
+	*[musig2.PubNonceSize]byte, *[musig2.PubNonceSize]byte, error) {
+
+	chanIDCopy := make([]byte, 32)
+	copy(chanIDCopy, chanID[:])
+
+	var node, btc [musig2.PubNonceSize]byte
+	err := kvdb.View(c.backend, func(tx kvdb.RTx) error {
+		bucket := tx.ReadBucket(announcementNoncesBucket)
+		if bucket == nil {
+			return ErrChannelNotFound
+		}
+
+		noncesBytes := bucket.Get(chanIDCopy)
+		if noncesBytes == nil {
+			return ErrChannelNotFound
+		}
+
+		if len(noncesBytes) != musig2.PubNonceSize*2 {
+			return fmt.Errorf("wrong number of bytes")
+		}
+
+		copy(node[:], noncesBytes[:musig2.PubNonceSize])
+		copy(btc[:], noncesBytes[musig2.PubNonceSize:])
+
+		return nil
+	}, func() {})
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return &node, &btc, nil
+}
+
+func (c *ChannelStateDB) DeleteAnnouncementNonces(
+	chanID lnwire.ChannelID) error {
+
+	chanIDCopy := make([]byte, 32)
+	copy(chanIDCopy, chanID[:])
+
+	return kvdb.Update(c.backend, func(tx kvdb.RwTx) error {
+		bucket := tx.ReadWriteBucket(
+			announcementNoncesBucket,
+		)
+		if bucket == nil {
+			return nil
+		}
+
+		return bucket.Delete(chanIDCopy)
+	}, func() {})
+}