package wtdb import ( "errors" "github.com/btcsuite/btcd/btcec" "github.com/lightningnetwork/lnd/lnwire" "github.com/lightningnetwork/lnd/watchtower/wtpolicy" ) var ( // ErrClientSessionNotFound signals that the requested client session // was not found in the database. ErrClientSessionNotFound = errors.New("client session not found") // ErrUpdateAlreadyCommitted signals that the chosen sequence number has // already been committed to an update with a different breach hint. ErrUpdateAlreadyCommitted = errors.New("update already committed") // ErrCommitUnorderedUpdate signals the client tried to commit a // sequence number other than the next unallocated sequence number. ErrCommitUnorderedUpdate = errors.New("update seqnum not monotonic") // ErrCommittedUpdateNotFound signals that the tower tried to ACK a // sequence number that has not yet been allocated by the client. ErrCommittedUpdateNotFound = errors.New("committed update not found") // ErrUnallocatedLastApplied signals that the tower tried to provide a // LastApplied value greater than any allocated sequence number. ErrUnallocatedLastApplied = errors.New("tower echoed last appiled " + "greater than allocated seqnum") ) // ClientSession encapsulates a SessionInfo returned from a successful // session negotiation, and also records the tower and ephemeral secret used for // communicating with the tower. type ClientSession struct { // ID is the client's public key used when authenticating with the // tower. ID SessionID // SeqNum is the next unallocated sequence number that can be sent to // the tower. SeqNum uint16 // TowerLastApplied the last last-applied the tower has echoed back. TowerLastApplied uint16 // TowerID is the unique, db-assigned identifier that references the // Tower with which the session is negotiated. TowerID uint64 // Tower holds the pubkey and address of the watchtower. // // NOTE: This value is not serialized. It is recovered by looking up the // tower with TowerID. Tower *Tower // KeyIndex is the index of key locator used to derive the client's // session key so that it can authenticate with the tower to update its // session. In order to rederive the private key, the key locator should // use the keychain.KeyFamilyTowerSession key family. KeyIndex uint32 // SessionPrivKey is the ephemeral secret key used to connect to the // watchtower. // // NOTE: This value is not serialized. It is derived using the KeyIndex // on startup to avoid storing private keys on disk. SessionPrivKey *btcec.PrivateKey // Policy holds the negotiated session parameters. Policy wtpolicy.Policy // RewardPkScript is the pkscript that the tower's reward will be // deposited to if a sweep transaction confirms and the sessions // specifies a reward output. RewardPkScript []byte // CommittedUpdates is a map from allocated sequence numbers to unacked // updates. These updates can be resent after a restart if the update // failed to send or receive an acknowledgment. CommittedUpdates map[uint16]*CommittedUpdate // AckedUpdates is a map from sequence number to backup id to record // which revoked states were uploaded via this session. AckedUpdates map[uint16]BackupID } // BackupID identifies a particular revoked, remote commitment by channel id and // commitment height. type BackupID struct { // ChanID is the channel id of the revoked commitment. ChanID lnwire.ChannelID // CommitHeight is the commitment height of the revoked commitment. CommitHeight uint64 } // CommittedUpdate holds a state update sent by a client along with its // SessionID. type CommittedUpdate struct { BackupID BackupID // Hint is the 16-byte prefix of the revoked commitment transaction ID. Hint BreachHint // EncryptedBlob is a ciphertext containing the sweep information for // exacting justice if the commitment transaction matching the breach // hint is braodcast. EncryptedBlob []byte }