package channeldb import ( "bytes" "encoding/binary" "errors" "io" "github.com/coreos/bbolt" "github.com/lightningnetwork/lnd/lnwire" ) var ( // paymentBucket is the name of the bucket within the database that // stores all data related to payments. // // Within the payments bucket, each invoice is keyed by its invoice ID // which is a monotonically increasing uint64. BoltDB's sequence // feature is used for generating monotonically increasing id. paymentBucket = []byte("payments") // paymentStatusBucket is the name of the bucket within the database that // stores the status of a payment indexed by the payment's preimage. paymentStatusBucket = []byte("payment-status") ) // PaymentStatus represent current status of payment type PaymentStatus byte const ( // StatusGrounded is the status where a payment has never been // initiated, or has been initiated and received an intermittent // failure. StatusGrounded PaymentStatus = 0 // StatusInFlight is the status where a payment has been initiated, but // a response has not been received. StatusInFlight PaymentStatus = 1 // StatusCompleted is the status where a payment has been initiated and // the payment was completed successfully. StatusCompleted PaymentStatus = 2 ) // Bytes returns status as slice of bytes. func (ps PaymentStatus) Bytes() []byte { return []byte{byte(ps)} } // FromBytes sets status from slice of bytes. func (ps *PaymentStatus) FromBytes(status []byte) error { if len(status) != 1 { return errors.New("payment status is empty") } switch PaymentStatus(status[0]) { case StatusGrounded, StatusInFlight, StatusCompleted: *ps = PaymentStatus(status[0]) default: return errors.New("unknown payment status") } return nil } // String returns readable representation of payment status. func (ps PaymentStatus) String() string { switch ps { case StatusGrounded: return "Grounded" case StatusInFlight: return "In Flight" case StatusCompleted: return "Completed" default: return "Unknown" } } // OutgoingPayment represents a successful payment between the daemon and a // remote node. Details such as the total fee paid, and the time of the payment // are stored. type OutgoingPayment struct { Invoice // Fee is the total fee paid for the payment in milli-satoshis. Fee lnwire.MilliSatoshi // TotalTimeLock is the total cumulative time-lock in the HTLC extended // from the second-to-last hop to the destination. TimeLockLength uint32 // Path encodes the path the payment took through the network. The path // excludes the outgoing node and consists of the hex-encoded // compressed public key of each of the nodes involved in the payment. Path [][33]byte // PaymentPreimage is the preImage of a successful payment. This is used // to calculate the PaymentHash as well as serve as a proof of payment. PaymentPreimage [32]byte } // AddPayment saves a successful payment to the database. It is assumed that // all payment are sent using unique payment hashes. func (db *DB) AddPayment(payment *OutgoingPayment) error { // Validate the field of the inner voice within the outgoing payment, // these must also adhere to the same constraints as regular invoices. if err := validateInvoice(&payment.Invoice); err != nil { return err } // We first serialize the payment before starting the database // transaction so we can avoid creating a DB payment in the case of a // serialization error. var b bytes.Buffer if err := serializeOutgoingPayment(&b, payment); err != nil { return err } paymentBytes := b.Bytes() return db.Batch(func(tx *bolt.Tx) error { payments, err := tx.CreateBucketIfNotExists(paymentBucket) if err != nil { return err } // Obtain the new unique sequence number for this payment. paymentID, err := payments.NextSequence() if err != nil { return err } // We use BigEndian for keys as it orders keys in // ascending order. This allows bucket scans to order payments // in the order in which they were created. paymentIDBytes := make([]byte, 8) binary.BigEndian.PutUint64(paymentIDBytes, paymentID) return payments.Put(paymentIDBytes, paymentBytes) }) } // FetchAllPayments returns all outgoing payments in DB. func (db *DB) FetchAllPayments() ([]*OutgoingPayment, error) { var payments []*OutgoingPayment err := db.View(func(tx *bolt.Tx) error { bucket := tx.Bucket(paymentBucket) if bucket == nil { return ErrNoPaymentsCreated } return bucket.ForEach(func(k, v []byte) error { // If the value is nil, then we ignore it as it may be // a sub-bucket. if v == nil { return nil } r := bytes.NewReader(v) payment, err := deserializeOutgoingPayment(r) if err != nil { return err } payments = append(payments, payment) return nil }) }) if err != nil { return nil, err } return payments, nil } // DeleteAllPayments deletes all payments from DB. func (db *DB) DeleteAllPayments() error { return db.Update(func(tx *bolt.Tx) error { err := tx.DeleteBucket(paymentBucket) if err != nil && err != bolt.ErrBucketNotFound { return err } _, err = tx.CreateBucket(paymentBucket) return err }) } // UpdatePaymentStatus sets the payment status for outgoing/finished payments in // local database. func (db *DB) UpdatePaymentStatus(paymentHash [32]byte, status PaymentStatus) error { return db.Batch(func(tx *bolt.Tx) error { return UpdatePaymentStatusTx(tx, paymentHash, status) }) } // UpdatePaymentStatusTx is a helper method that sets the payment status for // outgoing/finished payments in the local database. This method accepts a // boltdb transaction such that the operation can be composed into other // database transactions. func UpdatePaymentStatusTx(tx *bolt.Tx, paymentHash [32]byte, status PaymentStatus) error { paymentStatuses, err := tx.CreateBucketIfNotExists(paymentStatusBucket) if err != nil { return err } return paymentStatuses.Put(paymentHash[:], status.Bytes()) } // FetchPaymentStatus returns the payment status for outgoing payment. // If status of the payment isn't found, it will default to "StatusGrounded". func (db *DB) FetchPaymentStatus(paymentHash [32]byte) (PaymentStatus, error) { var paymentStatus = StatusGrounded err := db.View(func(tx *bolt.Tx) error { var err error paymentStatus, err = FetchPaymentStatusTx(tx, paymentHash) return err }) if err != nil { return StatusGrounded, err } return paymentStatus, nil } // FetchPaymentStatusTx is a helper method that returns the payment status for // outgoing payment. If status of the payment isn't found, it will default to // "StatusGrounded". It accepts the boltdb transactions such that this method // can be composed into other atomic operations. func FetchPaymentStatusTx(tx *bolt.Tx, paymentHash [32]byte) (PaymentStatus, error) { // The default status for all payments that aren't recorded in database. var paymentStatus = StatusGrounded bucket := tx.Bucket(paymentStatusBucket) if bucket == nil { return paymentStatus, nil } paymentStatusBytes := bucket.Get(paymentHash[:]) if paymentStatusBytes == nil { return paymentStatus, nil } paymentStatus.FromBytes(paymentStatusBytes) return paymentStatus, nil } func serializeOutgoingPayment(w io.Writer, p *OutgoingPayment) error { var scratch [8]byte if err := serializeInvoice(w, &p.Invoice); err != nil { return err } byteOrder.PutUint64(scratch[:], uint64(p.Fee)) if _, err := w.Write(scratch[:]); err != nil { return err } // First write out the length of the bytes to prefix the value. pathLen := uint32(len(p.Path)) byteOrder.PutUint32(scratch[:4], pathLen) if _, err := w.Write(scratch[:4]); err != nil { return err } // Then with the path written, we write out the series of public keys // involved in the path. for _, hop := range p.Path { if _, err := w.Write(hop[:]); err != nil { return err } } byteOrder.PutUint32(scratch[:4], p.TimeLockLength) if _, err := w.Write(scratch[:4]); err != nil { return err } if _, err := w.Write(p.PaymentPreimage[:]); err != nil { return err } return nil } func deserializeOutgoingPayment(r io.Reader) (*OutgoingPayment, error) { var scratch [8]byte p := &OutgoingPayment{} inv, err := deserializeInvoice(r) if err != nil { return nil, err } p.Invoice = inv if _, err := r.Read(scratch[:]); err != nil { return nil, err } p.Fee = lnwire.MilliSatoshi(byteOrder.Uint64(scratch[:])) if _, err = r.Read(scratch[:4]); err != nil { return nil, err } pathLen := byteOrder.Uint32(scratch[:4]) path := make([][33]byte, pathLen) for i := uint32(0); i < pathLen; i++ { if _, err := r.Read(path[i][:]); err != nil { return nil, err } } p.Path = path if _, err = r.Read(scratch[:4]); err != nil { return nil, err } p.TimeLockLength = byteOrder.Uint32(scratch[:4]) if _, err := r.Read(p.PaymentPreimage[:]); err != nil { return nil, err } return p, nil }