package migration_01_to_11 import ( "bytes" "encoding/binary" "fmt" "io" "time" "github.com/btcsuite/btcd/wire" "github.com/lightningnetwork/lnd/channeldb/kvdb" "github.com/lightningnetwork/lnd/lntypes" "github.com/lightningnetwork/lnd/lnwire" "github.com/lightningnetwork/lnd/tlv" ) var ( // invoiceBucket is the name of the bucket within the database that // stores all data related to invoices no matter their final state. // Within the invoice bucket, each invoice is keyed by its invoice ID // which is a monotonically increasing uint32. invoiceBucket = []byte("invoices") // addIndexBucket is an index bucket that we'll use to create a // monotonically increasing set of add indexes. Each time we add a new // invoice, this sequence number will be incremented and then populated // within the new invoice. // // In addition to this sequence number, we map: // // addIndexNo => invoiceKey addIndexBucket = []byte("invoice-add-index") // settleIndexBucket is an index bucket that we'll use to create a // monotonically increasing integer for tracking a "settle index". Each // time an invoice is settled, this sequence number will be incremented // as populate within the newly settled invoice. // // In addition to this sequence number, we map: // // settleIndexNo => invoiceKey settleIndexBucket = []byte("invoice-settle-index") ) const ( // MaxMemoSize is maximum size of the memo field within invoices stored // in the database. MaxMemoSize = 1024 // MaxReceiptSize is the maximum size of the payment receipt stored // within the database along side incoming/outgoing invoices. MaxReceiptSize = 1024 // MaxPaymentRequestSize is the max size of a payment request for // this invoice. // TODO(halseth): determine the max length payment request when field // lengths are final. MaxPaymentRequestSize = 4096 // A set of tlv type definitions used to serialize invoice htlcs to the // database. chanIDType tlv.Type = 1 htlcIDType tlv.Type = 3 amtType tlv.Type = 5 acceptHeightType tlv.Type = 7 acceptTimeType tlv.Type = 9 resolveTimeType tlv.Type = 11 expiryHeightType tlv.Type = 13 stateType tlv.Type = 15 ) // ContractState describes the state the invoice is in. type ContractState uint8 const ( // ContractOpen means the invoice has only been created. ContractOpen ContractState = 0 // ContractSettled means the htlc is settled and the invoice has been // paid. ContractSettled ContractState = 1 // ContractCanceled means the invoice has been canceled. ContractCanceled ContractState = 2 // ContractAccepted means the HTLC has been accepted but not settled // yet. ContractAccepted ContractState = 3 ) // String returns a human readable identifier for the ContractState type. func (c ContractState) String() string { switch c { case ContractOpen: return "Open" case ContractSettled: return "Settled" case ContractCanceled: return "Canceled" case ContractAccepted: return "Accepted" } return "Unknown" } // ContractTerm is a companion struct to the Invoice struct. This struct houses // the necessary conditions required before the invoice can be considered fully // settled by the payee. type ContractTerm struct { // PaymentPreimage is the preimage which is to be revealed in the // occasion that an HTLC paying to the hash of this preimage is // extended. PaymentPreimage lntypes.Preimage // Value is the expected amount of milli-satoshis to be paid to an HTLC // which can be satisfied by the above preimage. Value lnwire.MilliSatoshi // State describes the state the invoice is in. State ContractState } // Invoice is a payment invoice generated by a payee in order to request // payment for some good or service. The inclusion of invoices within Lightning // creates a payment work flow for merchants very similar to that of the // existing financial system within PayPal, etc. Invoices are added to the // database when a payment is requested, then can be settled manually once the // payment is received at the upper layer. For record keeping purposes, // invoices are never deleted from the database, instead a bit is toggled // denoting the invoice has been fully settled. Within the database, all // invoices must have a unique payment hash which is generated by taking the // sha256 of the payment preimage. type Invoice struct { // Memo is an optional memo to be stored along side an invoice. The // memo may contain further details pertaining to the invoice itself, // or any other message which fits within the size constraints. Memo []byte // Receipt is an optional field dedicated for storing a // cryptographically binding receipt of payment. // // TODO(roasbeef): document scheme. Receipt []byte // PaymentRequest is an optional field where a payment request created // for this invoice can be stored. PaymentRequest []byte // FinalCltvDelta is the minimum required number of blocks before htlc // expiry when the invoice is accepted. FinalCltvDelta int32 // Expiry defines how long after creation this invoice should expire. Expiry time.Duration // CreationDate is the exact time the invoice was created. CreationDate time.Time // SettleDate is the exact time the invoice was settled. SettleDate time.Time // Terms are the contractual payment terms of the invoice. Once all the // terms have been satisfied by the payer, then the invoice can be // considered fully fulfilled. // // TODO(roasbeef): later allow for multiple terms to fulfill the final // invoice: payment fragmentation, etc. Terms ContractTerm // AddIndex is an auto-incrementing integer that acts as a // monotonically increasing sequence number for all invoices created. // Clients can then use this field as a "checkpoint" of sorts when // implementing a streaming RPC to notify consumers of instances where // an invoice has been added before they re-connected. // // NOTE: This index starts at 1. AddIndex uint64 // SettleIndex is an auto-incrementing integer that acts as a // monotonically increasing sequence number for all settled invoices. // Clients can then use this field as a "checkpoint" of sorts when // implementing a streaming RPC to notify consumers of instances where // an invoice has been settled before they re-connected. // // NOTE: This index starts at 1. SettleIndex uint64 // AmtPaid is the final amount that we ultimately accepted for pay for // this invoice. We specify this value independently as it's possible // that the invoice originally didn't specify an amount, or the sender // overpaid. AmtPaid lnwire.MilliSatoshi // Htlcs records all htlcs that paid to this invoice. Some of these // htlcs may have been marked as canceled. Htlcs map[CircuitKey]*InvoiceHTLC } // HtlcState defines the states an htlc paying to an invoice can be in. type HtlcState uint8 // InvoiceHTLC contains details about an htlc paying to this invoice. type InvoiceHTLC struct { // Amt is the amount that is carried by this htlc. Amt lnwire.MilliSatoshi // AcceptHeight is the block height at which the invoice registry // decided to accept this htlc as a payment to the invoice. At this // height, the invoice cltv delay must have been met. AcceptHeight uint32 // AcceptTime is the wall clock time at which the invoice registry // decided to accept the htlc. AcceptTime time.Time // ResolveTime is the wall clock time at which the invoice registry // decided to settle the htlc. ResolveTime time.Time // Expiry is the expiry height of this htlc. Expiry uint32 // State indicates the state the invoice htlc is currently in. A // canceled htlc isn't just removed from the invoice htlcs map, because // we need AcceptHeight to properly cancel the htlc back. State HtlcState } func validateInvoice(i *Invoice) error { if len(i.Memo) > MaxMemoSize { return fmt.Errorf("max length a memo is %v, and invoice "+ "of length %v was provided", MaxMemoSize, len(i.Memo)) } if len(i.Receipt) > MaxReceiptSize { return fmt.Errorf("max length a receipt is %v, and invoice "+ "of length %v was provided", MaxReceiptSize, len(i.Receipt)) } if len(i.PaymentRequest) > MaxPaymentRequestSize { return fmt.Errorf("max length of payment request is %v, length "+ "provided was %v", MaxPaymentRequestSize, len(i.PaymentRequest)) } return nil } // FetchAllInvoices returns all invoices currently stored within the database. // If the pendingOnly param is true, then only unsettled invoices will be // returned, skipping all invoices that are fully settled. func (d *DB) FetchAllInvoices(pendingOnly bool) ([]Invoice, error) { var invoices []Invoice err := kvdb.View(d, func(tx kvdb.RTx) error { invoiceB := tx.ReadBucket(invoiceBucket) if invoiceB == nil { return ErrNoInvoicesCreated } // Iterate through the entire key space of the top-level // invoice bucket. If key with a non-nil value stores the next // invoice ID which maps to the corresponding invoice. return invoiceB.ForEach(func(k, v []byte) error { if v == nil { return nil } invoiceReader := bytes.NewReader(v) invoice, err := deserializeInvoice(invoiceReader) if err != nil { return err } if pendingOnly && invoice.Terms.State == ContractSettled { return nil } invoices = append(invoices, invoice) return nil }) }) if err != nil { return nil, err } return invoices, nil } // serializeInvoice serializes an invoice to a writer. // // Note: this function is in use for a migration. Before making changes that // would modify the on disk format, make a copy of the original code and store // it with the migration. func serializeInvoice(w io.Writer, i *Invoice) error { if err := wire.WriteVarBytes(w, 0, i.Memo[:]); err != nil { return err } if err := wire.WriteVarBytes(w, 0, i.Receipt[:]); err != nil { return err } if err := wire.WriteVarBytes(w, 0, i.PaymentRequest[:]); err != nil { return err } if err := binary.Write(w, byteOrder, i.FinalCltvDelta); err != nil { return err } if err := binary.Write(w, byteOrder, int64(i.Expiry)); err != nil { return err } birthBytes, err := i.CreationDate.MarshalBinary() if err != nil { return err } if err := wire.WriteVarBytes(w, 0, birthBytes); err != nil { return err } settleBytes, err := i.SettleDate.MarshalBinary() if err != nil { return err } if err := wire.WriteVarBytes(w, 0, settleBytes); err != nil { return err } if _, err := w.Write(i.Terms.PaymentPreimage[:]); err != nil { return err } var scratch [8]byte byteOrder.PutUint64(scratch[:], uint64(i.Terms.Value)) if _, err := w.Write(scratch[:]); err != nil { return err } if err := binary.Write(w, byteOrder, i.Terms.State); err != nil { return err } if err := binary.Write(w, byteOrder, i.AddIndex); err != nil { return err } if err := binary.Write(w, byteOrder, i.SettleIndex); err != nil { return err } if err := binary.Write(w, byteOrder, int64(i.AmtPaid)); err != nil { return err } if err := serializeHtlcs(w, i.Htlcs); err != nil { return err } return nil } // serializeHtlcs serializes a map containing circuit keys and invoice htlcs to // a writer. func serializeHtlcs(w io.Writer, htlcs map[CircuitKey]*InvoiceHTLC) error { for key, htlc := range htlcs { // Encode the htlc in a tlv stream. chanID := key.ChanID.ToUint64() amt := uint64(htlc.Amt) acceptTime := uint64(htlc.AcceptTime.UnixNano()) resolveTime := uint64(htlc.ResolveTime.UnixNano()) state := uint8(htlc.State) tlvStream, err := tlv.NewStream( tlv.MakePrimitiveRecord(chanIDType, &chanID), tlv.MakePrimitiveRecord(htlcIDType, &key.HtlcID), tlv.MakePrimitiveRecord(amtType, &amt), tlv.MakePrimitiveRecord( acceptHeightType, &htlc.AcceptHeight, ), tlv.MakePrimitiveRecord(acceptTimeType, &acceptTime), tlv.MakePrimitiveRecord(resolveTimeType, &resolveTime), tlv.MakePrimitiveRecord(expiryHeightType, &htlc.Expiry), tlv.MakePrimitiveRecord(stateType, &state), ) if err != nil { return err } var b bytes.Buffer if err := tlvStream.Encode(&b); err != nil { return err } // Write the length of the tlv stream followed by the stream // bytes. err = binary.Write(w, byteOrder, uint64(b.Len())) if err != nil { return err } if _, err := w.Write(b.Bytes()); err != nil { return err } } return nil } func deserializeInvoice(r io.Reader) (Invoice, error) { var err error invoice := Invoice{} // TODO(roasbeef): use read full everywhere invoice.Memo, err = wire.ReadVarBytes(r, 0, MaxMemoSize, "") if err != nil { return invoice, err } invoice.Receipt, err = wire.ReadVarBytes(r, 0, MaxReceiptSize, "") if err != nil { return invoice, err } invoice.PaymentRequest, err = wire.ReadVarBytes(r, 0, MaxPaymentRequestSize, "") if err != nil { return invoice, err } if err := binary.Read(r, byteOrder, &invoice.FinalCltvDelta); err != nil { return invoice, err } var expiry int64 if err := binary.Read(r, byteOrder, &expiry); err != nil { return invoice, err } invoice.Expiry = time.Duration(expiry) birthBytes, err := wire.ReadVarBytes(r, 0, 300, "birth") if err != nil { return invoice, err } if err := invoice.CreationDate.UnmarshalBinary(birthBytes); err != nil { return invoice, err } settledBytes, err := wire.ReadVarBytes(r, 0, 300, "settled") if err != nil { return invoice, err } if err := invoice.SettleDate.UnmarshalBinary(settledBytes); err != nil { return invoice, err } if _, err := io.ReadFull(r, invoice.Terms.PaymentPreimage[:]); err != nil { return invoice, err } var scratch [8]byte if _, err := io.ReadFull(r, scratch[:]); err != nil { return invoice, err } invoice.Terms.Value = lnwire.MilliSatoshi(byteOrder.Uint64(scratch[:])) if err := binary.Read(r, byteOrder, &invoice.Terms.State); err != nil { return invoice, err } if err := binary.Read(r, byteOrder, &invoice.AddIndex); err != nil { return invoice, err } if err := binary.Read(r, byteOrder, &invoice.SettleIndex); err != nil { return invoice, err } if err := binary.Read(r, byteOrder, &invoice.AmtPaid); err != nil { return invoice, err } invoice.Htlcs, err = deserializeHtlcs(r) if err != nil { return Invoice{}, err } return invoice, nil } // deserializeHtlcs reads a list of invoice htlcs from a reader and returns it // as a map. func deserializeHtlcs(r io.Reader) (map[CircuitKey]*InvoiceHTLC, error) { htlcs := make(map[CircuitKey]*InvoiceHTLC, 0) for { // Read the length of the tlv stream for this htlc. var streamLen uint64 if err := binary.Read(r, byteOrder, &streamLen); err != nil { if err == io.EOF { break } return nil, err } streamBytes := make([]byte, streamLen) if _, err := r.Read(streamBytes); err != nil { return nil, err } streamReader := bytes.NewReader(streamBytes) // Decode the contents into the htlc fields. var ( htlc InvoiceHTLC key CircuitKey chanID uint64 state uint8 acceptTime, resolveTime uint64 amt uint64 ) tlvStream, err := tlv.NewStream( tlv.MakePrimitiveRecord(chanIDType, &chanID), tlv.MakePrimitiveRecord(htlcIDType, &key.HtlcID), tlv.MakePrimitiveRecord(amtType, &amt), tlv.MakePrimitiveRecord( acceptHeightType, &htlc.AcceptHeight, ), tlv.MakePrimitiveRecord(acceptTimeType, &acceptTime), tlv.MakePrimitiveRecord(resolveTimeType, &resolveTime), tlv.MakePrimitiveRecord(expiryHeightType, &htlc.Expiry), tlv.MakePrimitiveRecord(stateType, &state), ) if err != nil { return nil, err } if err := tlvStream.Decode(streamReader); err != nil { return nil, err } key.ChanID = lnwire.NewShortChanIDFromInt(chanID) htlc.AcceptTime = time.Unix(0, int64(acceptTime)) htlc.ResolveTime = time.Unix(0, int64(resolveTime)) htlc.State = HtlcState(state) htlc.Amt = lnwire.MilliSatoshi(amt) htlcs[key] = &htlc } return htlcs, nil }