package wtclient import ( "net" "github.com/btcsuite/btcd/btcec" "github.com/lightningnetwork/lnd/brontide" "github.com/lightningnetwork/lnd/lnwire" "github.com/lightningnetwork/lnd/watchtower/wtdb" "github.com/lightningnetwork/lnd/watchtower/wtserver" ) // DB abstracts the required database operations required by the watchtower // client. type DB interface { // CreateTower initialize an address record used to communicate with a // watchtower. Each Tower is assigned a unique ID, that is used to // amortize storage costs of the public key when used by multiple // sessions. CreateTower(*lnwire.NetAddress) (*wtdb.Tower, error) // CreateClientSession saves a newly negotiated client session to the // client's database. This enables the session to be used across // restarts. CreateClientSession(*wtdb.ClientSession) error // ListClientSessions returns all sessions that have not yet been // exhausted. This is used on startup to find any sessions which may // still be able to accept state updates. ListClientSessions() (map[wtdb.SessionID]*wtdb.ClientSession, error) // FetchChanPkScripts returns a map of all sweep pkscripts for // registered channels. This is used on startup to cache the sweep // pkscripts of registered channels in memory. FetchChanPkScripts() (map[lnwire.ChannelID][]byte, error) // AddChanPkScript inserts a newly generated sweep pkscript for the // given channel. AddChanPkScript(lnwire.ChannelID, []byte) error // MarkBackupIneligible records that the state identified by the // (channel id, commit height) tuple was ineligible for being backed up // under the current policy. This state can be retried later under a // different policy. MarkBackupIneligible(chanID lnwire.ChannelID, commitHeight uint64) error // CommitUpdate writes the next state update for a particular // session, so that we can be sure to resend it after a restart if it // hasn't been ACK'd by the tower. The sequence number of the update // should be exactly one greater than the existing entry, and less that // or equal to the session's MaxUpdates. CommitUpdate(id *wtdb.SessionID, seqNum uint16, update *wtdb.CommittedUpdate) (uint16, error) // AckUpdate records an acknowledgment from the watchtower that the // update identified by seqNum was received and saved. The returned // lastApplied will be recorded. AckUpdate(id *wtdb.SessionID, seqNum, lastApplied uint16) error } // Dial connects to an addr using the specified net and returns the connection // object. type Dial func(net, addr string) (net.Conn, error) // AuthDialer connects to a remote node using an authenticated transport, such as // brontide. The dialer argument is used to specify a resolver, which allows // this method to be used over Tor or clear net connections. type AuthDialer func(localPriv *btcec.PrivateKey, netAddr *lnwire.NetAddress, dialer func(string, string) (net.Conn, error)) (wtserver.Peer, error) // AuthDial is the watchtower client's default method of dialing. func AuthDial(localPriv *btcec.PrivateKey, netAddr *lnwire.NetAddress, dialer func(string, string) (net.Conn, error)) (wtserver.Peer, error) { return brontide.Dial(localPriv, netAddr, dialer) }