package channeldb import ( "bytes" "encoding/binary" "errors" "fmt" "io" "sort" "time" "github.com/btcsuite/btcd/btcec" "github.com/coreos/bbolt" "github.com/lightningnetwork/lnd/lntypes" "github.com/lightningnetwork/lnd/lnwire" "github.com/lightningnetwork/lnd/routing/route" ) var ( // paymentsRootBucket is the name of the top-level bucket within the // database that stores all data related to payments. Within this // bucket, each payment hash its own sub-bucket keyed by its payment // hash. // // Bucket hierarchy: // // root-bucket // | // |-- // | |--sequence-key: // | |--creation-info-key: // | |--attempt-info-key: // | |--settle-info-key: // | |--fail-info-key: // | | // | |--duplicate-bucket (only for old, completed payments) // | | // | |-- // | | |--sequence-key: // | | |--creation-info-key: // | | |--attempt-info-key: // | | |--settle-info-key: // | | |--fail-info-key: // | | // | |-- // | | | // | ... ... // | // |-- // | | // | ... // ... // paymentsRootBucket = []byte("payments-root-bucket") // paymentDublicateBucket is the name of a optional sub-bucket within // the payment hash bucket, that is used to hold duplicate payments to // a payment hash. This is needed to support information from earlier // versions of lnd, where it was possible to pay to a payment hash more // than once. paymentDuplicateBucket = []byte("payment-duplicate-bucket") // paymentSequenceKey is a key used in the payment's sub-bucket to // store the sequence number of the payment. paymentSequenceKey = []byte("payment-sequence-key") // paymentCreationInfoKey is a key used in the payment's sub-bucket to // store the creation info of the payment. paymentCreationInfoKey = []byte("payment-creation-info") // paymentAttemptInfoKey is a key used in the payment's sub-bucket to // store the info about the latest attempt that was done for the // payment in question. paymentAttemptInfoKey = []byte("payment-attempt-info") // paymentSettleInfoKey is a key used in the payment's sub-bucket to // store the settle info of the payment. paymentSettleInfoKey = []byte("payment-settle-info") // paymentFailInfoKey is a key used in the payment's sub-bucket to // store information about the reason a payment failed. paymentFailInfoKey = []byte("payment-fail-info") ) // FailureReason encodes the reason a payment ultimately failed. type FailureReason byte const ( // FailureReasonTimeout indicates that the payment did timeout before a // successful payment attempt was made. FailureReasonTimeout FailureReason = 0 // FailureReasonNoRoute indicates no successful route to the // destination was found during path finding. FailureReasonNoRoute FailureReason = 1 // TODO(halseth): cancel state. // TODO(joostjager): Add failure reasons for: // UnknownPaymentHash, FinalInvalidAmt, FinalInvalidCltv // LocalLiquidityInsufficient, RemoteCapacityInsufficient. ) // String returns a human readable FailureReason func (r FailureReason) String() string { switch r { case FailureReasonTimeout: return "timeout" case FailureReasonNoRoute: return "no_route" } return "unknown" } // PaymentStatus represent current status of payment type PaymentStatus byte const ( // StatusUnknown is the status where a payment has never been initiated // and hence is unknown. StatusUnknown PaymentStatus = 0 // StatusInFlight is the status where a payment has been initiated, but // a response has not been received. StatusInFlight PaymentStatus = 1 // StatusSucceeded is the status where a payment has been initiated and // the payment was completed successfully. StatusSucceeded PaymentStatus = 2 // StatusFailed is the status where a payment has been initiated and a // failure result has come back. StatusFailed PaymentStatus = 3 ) // 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 StatusUnknown, StatusInFlight, StatusSucceeded, StatusFailed: *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 StatusUnknown: return "Unknown" case StatusInFlight: return "In Flight" case StatusSucceeded: return "Succeeded" case StatusFailed: return "Failed" default: return "Unknown" } } // PaymentCreationInfo is the information necessary to have ready when // initiating a payment, moving it into state InFlight. type PaymentCreationInfo struct { // PaymentHash is the hash this payment is paying to. PaymentHash lntypes.Hash // Value is the amount we are paying. Value lnwire.MilliSatoshi // CreatingDate is the time when this payment was initiated. CreationDate time.Time // PaymentRequest is the full payment request, if any. PaymentRequest []byte } // PaymentAttemptInfo contains information about a specific payment attempt for // a given payment. This information is used by the router to handle any errors // coming back after an attempt is made, and to query the switch about the // status of a payment. For settled payment this will be the information for // the succeeding payment attempt. type PaymentAttemptInfo struct { // PaymentID is the unique ID used for this attempt. PaymentID uint64 // SessionKey is the ephemeral key used for this payment attempt. SessionKey *btcec.PrivateKey // Route is the route attempted to send the HTLC. Route route.Route } // Payment is a wrapper around a payment's PaymentCreationInfo, // PaymentAttemptInfo, and preimage. All payments will have the // PaymentCreationInfo set, the PaymentAttemptInfo will be set only if at least // one payment attempt has been made, while only completed payments will have a // non-zero payment preimage. type Payment struct { // sequenceNum is a unique identifier used to sort the payments in // order of creation. sequenceNum uint64 // Status is the current PaymentStatus of this payment. Status PaymentStatus // Info holds all static information about this payment, and is // populated when the payment is initiated. Info *PaymentCreationInfo // Attempt is the information about the last payment attempt made. // // NOTE: Can be nil if no attempt is yet made. Attempt *PaymentAttemptInfo // PaymentPreimage is the preimage of a successful payment. This serves // as a proof of payment. It will only be non-nil for settled payments. // // NOTE: Can be nil if payment is not settled. PaymentPreimage *lntypes.Preimage // Failure is a failure reason code indicating the reason the payment // failed. It is only non-nil for failed payments. // // NOTE: Can be nil if payment is not failed. Failure *FailureReason } // FetchPayments returns all sent payments found in the DB. func (db *DB) FetchPayments() ([]*Payment, error) { var payments []*Payment err := db.View(func(tx *bbolt.Tx) error { paymentsBucket := tx.Bucket(paymentsRootBucket) if paymentsBucket == nil { return nil } return paymentsBucket.ForEach(func(k, v []byte) error { bucket := paymentsBucket.Bucket(k) if bucket == nil { // We only expect sub-buckets to be found in // this top-level bucket. return fmt.Errorf("non bucket element in " + "payments bucket") } p, err := fetchPayment(bucket) if err != nil { return err } payments = append(payments, p) // For older versions of lnd, duplicate payments to a // payment has was possible. These will be found in a // sub-bucket indexed by their sequence number if // available. dup := bucket.Bucket(paymentDuplicateBucket) if dup == nil { return nil } return dup.ForEach(func(k, v []byte) error { subBucket := dup.Bucket(k) if subBucket == nil { // We one bucket for each duplicate to // be found. return fmt.Errorf("non bucket element" + "in duplicate bucket") } p, err := fetchPayment(subBucket) if err != nil { return err } payments = append(payments, p) return nil }) }) }) if err != nil { return nil, err } // Before returning, sort the payments by their sequence number. sort.Slice(payments, func(i, j int) bool { return payments[i].sequenceNum < payments[j].sequenceNum }) return payments, nil } func fetchPayment(bucket *bbolt.Bucket) (*Payment, error) { var ( err error p = &Payment{} ) seqBytes := bucket.Get(paymentSequenceKey) if seqBytes == nil { return nil, fmt.Errorf("sequence number not found") } p.sequenceNum = binary.BigEndian.Uint64(seqBytes) // Get the payment status. p.Status = fetchPaymentStatus(bucket) // Get the PaymentCreationInfo. b := bucket.Get(paymentCreationInfoKey) if b == nil { return nil, fmt.Errorf("creation info not found") } r := bytes.NewReader(b) p.Info, err = deserializePaymentCreationInfo(r) if err != nil { return nil, err } // Get the PaymentAttemptInfo. This can be unset. b = bucket.Get(paymentAttemptInfoKey) if b != nil { r = bytes.NewReader(b) p.Attempt, err = deserializePaymentAttemptInfo(r) if err != nil { return nil, err } } // Get the payment preimage. This is only found for // completed payments. b = bucket.Get(paymentSettleInfoKey) if b != nil { var preimg lntypes.Preimage copy(preimg[:], b[:]) p.PaymentPreimage = &preimg } // Get failure reason if available. b = bucket.Get(paymentFailInfoKey) if b != nil { reason := FailureReason(b[0]) p.Failure = &reason } return p, nil } // DeletePayments deletes all completed and failed payments from the DB. func (db *DB) DeletePayments() error { return db.Update(func(tx *bbolt.Tx) error { payments := tx.Bucket(paymentsRootBucket) if payments == nil { return nil } var deleteBuckets [][]byte err := payments.ForEach(func(k, _ []byte) error { bucket := payments.Bucket(k) if bucket == nil { // We only expect sub-buckets to be found in // this top-level bucket. return fmt.Errorf("non bucket element in " + "payments bucket") } // If the status is InFlight, we cannot safely delete // the payment information, so we return early. paymentStatus := fetchPaymentStatus(bucket) if paymentStatus == StatusInFlight { return nil } deleteBuckets = append(deleteBuckets, k) return nil }) if err != nil { return err } for _, k := range deleteBuckets { if err := payments.DeleteBucket(k); err != nil { return err } } return nil }) } func serializePaymentCreationInfo(w io.Writer, c *PaymentCreationInfo) error { var scratch [8]byte if _, err := w.Write(c.PaymentHash[:]); err != nil { return err } byteOrder.PutUint64(scratch[:], uint64(c.Value)) if _, err := w.Write(scratch[:]); err != nil { return err } byteOrder.PutUint64(scratch[:], uint64(c.CreationDate.Unix())) if _, err := w.Write(scratch[:]); err != nil { return err } byteOrder.PutUint32(scratch[:4], uint32(len(c.PaymentRequest))) if _, err := w.Write(scratch[:4]); err != nil { return err } if _, err := w.Write(c.PaymentRequest[:]); err != nil { return err } return nil } func deserializePaymentCreationInfo(r io.Reader) (*PaymentCreationInfo, error) { var scratch [8]byte c := &PaymentCreationInfo{} if _, err := io.ReadFull(r, c.PaymentHash[:]); err != nil { return nil, err } if _, err := io.ReadFull(r, scratch[:]); err != nil { return nil, err } c.Value = lnwire.MilliSatoshi(byteOrder.Uint64(scratch[:])) if _, err := io.ReadFull(r, scratch[:]); err != nil { return nil, err } c.CreationDate = time.Unix(int64(byteOrder.Uint64(scratch[:])), 0) if _, err := io.ReadFull(r, scratch[:4]); err != nil { return nil, err } reqLen := uint32(byteOrder.Uint32(scratch[:4])) payReq := make([]byte, reqLen) if reqLen > 0 { if _, err := io.ReadFull(r, payReq[:]); err != nil { return nil, err } } c.PaymentRequest = payReq return c, nil } func serializePaymentAttemptInfo(w io.Writer, a *PaymentAttemptInfo) error { if err := WriteElements(w, a.PaymentID, a.SessionKey); err != nil { return err } if err := serializeRoute(w, a.Route); err != nil { return err } return nil } func deserializePaymentAttemptInfo(r io.Reader) (*PaymentAttemptInfo, error) { a := &PaymentAttemptInfo{} err := ReadElements(r, &a.PaymentID, &a.SessionKey) if err != nil { return nil, err } a.Route, err = deserializeRoute(r) if err != nil { return nil, err } return a, nil } func serializeHop(w io.Writer, h *route.Hop) error { if err := WriteElements(w, h.PubKeyBytes[:], h.ChannelID, h.OutgoingTimeLock, h.AmtToForward, ); err != nil { return err } return nil } func deserializeHop(r io.Reader) (*route.Hop, error) { h := &route.Hop{} var pub []byte if err := ReadElements(r, &pub); err != nil { return nil, err } copy(h.PubKeyBytes[:], pub) if err := ReadElements(r, &h.ChannelID, &h.OutgoingTimeLock, &h.AmtToForward, ); err != nil { return nil, err } return h, nil } func serializeRoute(w io.Writer, r route.Route) error { if err := WriteElements(w, r.TotalTimeLock, r.TotalAmount, r.SourcePubKey[:], ); err != nil { return err } if err := WriteElements(w, uint32(len(r.Hops))); err != nil { return err } for _, h := range r.Hops { if err := serializeHop(w, h); err != nil { return err } } return nil } func deserializeRoute(r io.Reader) (route.Route, error) { rt := route.Route{} if err := ReadElements(r, &rt.TotalTimeLock, &rt.TotalAmount, ); err != nil { return rt, err } var pub []byte if err := ReadElements(r, &pub); err != nil { return rt, err } copy(rt.SourcePubKey[:], pub) var numHops uint32 if err := ReadElements(r, &numHops); err != nil { return rt, err } var hops []*route.Hop for i := uint32(0); i < numHops; i++ { hop, err := deserializeHop(r) if err != nil { return rt, err } hops = append(hops, hop) } rt.Hops = hops return rt, nil }