lnd.xprv/channeldb/migration_01_to_11/invoices.go
2021-05-07 14:18:56 +02:00

553 lines
16 KiB
Go

package migration_01_to_11
import (
"bytes"
"encoding/binary"
"fmt"
"io"
"time"
"github.com/btcsuite/btcd/wire"
lnwire "github.com/lightningnetwork/lnd/channeldb/migration/lnwire21"
"github.com/lightningnetwork/lnd/kvdb"
"github.com/lightningnetwork/lnd/lntypes"
"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
})
}, func() {
invoices = 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
}