lnd.xprv/channeldb/migration12/invoices.go
2019-11-22 02:24:28 -08:00

319 lines
9.5 KiB
Go

package migration12
import (
"bytes"
"encoding/binary"
"io"
"time"
"github.com/btcsuite/btcd/wire"
"github.com/lightningnetwork/lnd/lntypes"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/tlv"
)
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
memoType tlv.Type = 0
payReqType tlv.Type = 1
createTimeType tlv.Type = 2
settleTimeType tlv.Type = 3
addIndexType tlv.Type = 4
settleIndexType tlv.Type = 5
preimageType tlv.Type = 6
valueType tlv.Type = 7
cltvDeltaType tlv.Type = 8
expiryType tlv.Type = 9
paymentAddrType tlv.Type = 10
featuresType tlv.Type = 11
invStateType tlv.Type = 12
amtPaidType tlv.Type = 13
)
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")
// Big endian is the preferred byte order, due to cursor scans over
// integer keys iterating in order.
byteOrder = binary.BigEndian
)
// ContractState describes the state the invoice is in.
type ContractState uint8
// 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
// PaymentAddr is a randomly generated value include in the MPP record
// by the sender to prevent probing of the receiver.
PaymentAddr [32]byte
// Features is the feature vectors advertised on the payment request.
Features *lnwire.FeatureVector
}
// 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
// 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 []byte
}
// LegacyDeserializeInvoice decodes an invoice from the passed io.Reader using
// the pre-TLV serialization.
func LegacyDeserializeInvoice(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
}
_, 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 flattened byte slice.
func deserializeHtlcs(r io.Reader) ([]byte, error) {
var b bytes.Buffer
_, err := io.Copy(&b, r)
return b.Bytes(), err
}
// SerializeInvoice serializes an invoice to a writer.
//
// nolint: dupl
func SerializeInvoice(w io.Writer, i *Invoice) error {
creationDateBytes, err := i.CreationDate.MarshalBinary()
if err != nil {
return err
}
settleDateBytes, err := i.SettleDate.MarshalBinary()
if err != nil {
return err
}
var fb bytes.Buffer
err = i.Terms.Features.EncodeBase256(&fb)
if err != nil {
return err
}
featureBytes := fb.Bytes()
preimage := [32]byte(i.Terms.PaymentPreimage)
value := uint64(i.Terms.Value)
cltvDelta := uint32(i.FinalCltvDelta)
expiry := uint64(i.Expiry)
amtPaid := uint64(i.AmtPaid)
state := uint8(i.Terms.State)
tlvStream, err := tlv.NewStream(
// Memo and payreq.
tlv.MakePrimitiveRecord(memoType, &i.Memo),
tlv.MakePrimitiveRecord(payReqType, &i.PaymentRequest),
// Add/settle metadata.
tlv.MakePrimitiveRecord(createTimeType, &creationDateBytes),
tlv.MakePrimitiveRecord(settleTimeType, &settleDateBytes),
tlv.MakePrimitiveRecord(addIndexType, &i.AddIndex),
tlv.MakePrimitiveRecord(settleIndexType, &i.SettleIndex),
// Terms.
tlv.MakePrimitiveRecord(preimageType, &preimage),
tlv.MakePrimitiveRecord(valueType, &value),
tlv.MakePrimitiveRecord(cltvDeltaType, &cltvDelta),
tlv.MakePrimitiveRecord(expiryType, &expiry),
tlv.MakePrimitiveRecord(paymentAddrType, &i.Terms.PaymentAddr),
tlv.MakePrimitiveRecord(featuresType, &featureBytes),
// Invoice state.
tlv.MakePrimitiveRecord(invStateType, &state),
tlv.MakePrimitiveRecord(amtPaidType, &amtPaid),
)
if err != nil {
return err
}
var b bytes.Buffer
if err = tlvStream.Encode(&b); err != nil {
return err
}
err = binary.Write(w, byteOrder, uint64(b.Len()))
if err != nil {
return err
}
if _, err = w.Write(b.Bytes()); err != nil {
return err
}
return serializeHtlcs(w, i.Htlcs)
}
// serializeHtlcs writes a serialized list of invoice htlcs into a writer.
func serializeHtlcs(w io.Writer, htlcs []byte) error {
_, err := w.Write(htlcs)
return err
}