lnd.xprv/channeldb/invoices.go

1321 lines
38 KiB
Go

package channeldb
import (
"bytes"
"encoding/binary"
"errors"
"fmt"
"io"
"time"
"github.com/btcsuite/btcd/wire"
"github.com/coreos/bbolt"
"github.com/lightningnetwork/lnd/lntypes"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/tlv"
)
var (
// UnknownPreimage is an all-zeroes preimage that indicates that the
// preimage for this invoice is not yet known.
UnknownPreimage lntypes.Preimage
// 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")
// paymentHashIndexBucket is the name of the sub-bucket within the
// invoiceBucket which indexes all invoices by their payment hash. The
// payment hash is the sha256 of the invoice's payment preimage. This
// index is used to detect duplicates, and also to provide a fast path
// for looking up incoming HTLCs to determine if we're able to settle
// them fully.
//
// maps: payHash => invoiceKey
invoiceIndexBucket = []byte("paymenthashes")
// numInvoicesKey is the name of key which houses the auto-incrementing
// invoice ID which is essentially used as a primary key. With each
// invoice inserted, the primary key is incremented by one. This key is
// stored within the invoiceIndexBucket. Within the invoiceBucket
// invoices are uniquely identified by the invoice ID.
numInvoicesKey = []byte("nik")
// 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")
// ErrInvoiceAlreadySettled is returned when the invoice is already
// settled.
ErrInvoiceAlreadySettled = errors.New("invoice already settled")
// ErrInvoiceAlreadyCanceled is returned when the invoice is already
// canceled.
ErrInvoiceAlreadyCanceled = errors.New("invoice already canceled")
// ErrInvoiceAlreadyAccepted is returned when the invoice is already
// accepted.
ErrInvoiceAlreadyAccepted = errors.New("invoice already accepted")
// ErrInvoiceStillOpen is returned when the invoice is still open.
ErrInvoiceStillOpen = errors.New("invoice still open")
)
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 cancelled.
Htlcs map[CircuitKey]*InvoiceHTLC
}
// HtlcState defines the states an htlc paying to an invoice can be in.
type HtlcState uint8
const (
// HtlcStateAccepted indicates the htlc is locked-in, but not resolved.
HtlcStateAccepted HtlcState = iota
// HtlcStateCancelled indicates the htlc is cancelled back to the
// sender.
HtlcStateCancelled
// HtlcStateSettled indicates the htlc is settled.
HtlcStateSettled
)
// 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
// cancelled htlc isn't just removed from the invoice htlcs map, because
// we need AcceptedHeight to properly cancel the htlc back.
State HtlcState
}
// HtlcAcceptDesc describes the details of a newly accepted htlc.
type HtlcAcceptDesc struct {
// AcceptHeight is the block height at which this htlc was accepted.
AcceptHeight int32
// Amt is the amount that is carried by this htlc.
Amt lnwire.MilliSatoshi
// Expiry is the expiry height of this htlc.
Expiry uint32
}
// InvoiceUpdateDesc describes the changes that should be applied to the
// invoice.
type InvoiceUpdateDesc struct {
// State is the new state that this invoice should progress to.
State ContractState
// Htlcs describes the changes that need to be made to the invoice htlcs
// in the database. Htlc map entries with their value set should be
// added. If the map value is nil, the htlc should be cancelled.
Htlcs map[CircuitKey]*HtlcAcceptDesc
// Preimage must be set to the preimage when state is settled.
Preimage lntypes.Preimage
}
// InvoiceUpdateCallback is a callback used in the db transaction to update the
// invoice.
type InvoiceUpdateCallback = func(invoice *Invoice) (*InvoiceUpdateDesc, error)
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
}
// AddInvoice inserts the targeted invoice into the database. If the invoice has
// *any* payment hashes which already exists within the database, then the
// insertion will be aborted and rejected due to the strict policy banning any
// duplicate payment hashes. A side effect of this function is that it sets
// AddIndex on newInvoice.
func (d *DB) AddInvoice(newInvoice *Invoice, paymentHash lntypes.Hash) (
uint64, error) {
if err := validateInvoice(newInvoice); err != nil {
return 0, err
}
var invoiceAddIndex uint64
err := d.Update(func(tx *bbolt.Tx) error {
invoices, err := tx.CreateBucketIfNotExists(invoiceBucket)
if err != nil {
return err
}
invoiceIndex, err := invoices.CreateBucketIfNotExists(
invoiceIndexBucket,
)
if err != nil {
return err
}
addIndex, err := invoices.CreateBucketIfNotExists(
addIndexBucket,
)
if err != nil {
return err
}
// Ensure that an invoice an identical payment hash doesn't
// already exist within the index.
if invoiceIndex.Get(paymentHash[:]) != nil {
return ErrDuplicateInvoice
}
// If the current running payment ID counter hasn't yet been
// created, then create it now.
var invoiceNum uint32
invoiceCounter := invoiceIndex.Get(numInvoicesKey)
if invoiceCounter == nil {
var scratch [4]byte
byteOrder.PutUint32(scratch[:], invoiceNum)
err := invoiceIndex.Put(numInvoicesKey, scratch[:])
if err != nil {
return err
}
} else {
invoiceNum = byteOrder.Uint32(invoiceCounter)
}
newIndex, err := putInvoice(
invoices, invoiceIndex, addIndex, newInvoice, invoiceNum,
paymentHash,
)
if err != nil {
return err
}
invoiceAddIndex = newIndex
return nil
})
if err != nil {
return 0, err
}
return invoiceAddIndex, err
}
// InvoicesAddedSince can be used by callers to seek into the event time series
// of all the invoices added in the database. The specified sinceAddIndex
// should be the highest add index that the caller knows of. This method will
// return all invoices with an add index greater than the specified
// sinceAddIndex.
//
// NOTE: The index starts from 1, as a result. We enforce that specifying a
// value below the starting index value is a noop.
func (d *DB) InvoicesAddedSince(sinceAddIndex uint64) ([]Invoice, error) {
var newInvoices []Invoice
// If an index of zero was specified, then in order to maintain
// backwards compat, we won't send out any new invoices.
if sinceAddIndex == 0 {
return newInvoices, nil
}
var startIndex [8]byte
byteOrder.PutUint64(startIndex[:], sinceAddIndex)
err := d.DB.View(func(tx *bbolt.Tx) error {
invoices := tx.Bucket(invoiceBucket)
if invoices == nil {
return ErrNoInvoicesCreated
}
addIndex := invoices.Bucket(addIndexBucket)
if addIndex == nil {
return ErrNoInvoicesCreated
}
// We'll now run through each entry in the add index starting
// at our starting index. We'll continue until we reach the
// very end of the current key space.
invoiceCursor := addIndex.Cursor()
// We'll seek to the starting index, then manually advance the
// cursor in order to skip the entry with the since add index.
invoiceCursor.Seek(startIndex[:])
addSeqNo, invoiceKey := invoiceCursor.Next()
for ; addSeqNo != nil && bytes.Compare(addSeqNo, startIndex[:]) > 0; addSeqNo, invoiceKey = invoiceCursor.Next() {
// For each key found, we'll look up the actual
// invoice, then accumulate it into our return value.
invoice, err := fetchInvoice(invoiceKey, invoices)
if err != nil {
return err
}
newInvoices = append(newInvoices, invoice)
}
return nil
})
switch {
// If no invoices have been created, then we'll return the empty set of
// invoices.
case err == ErrNoInvoicesCreated:
case err != nil:
return nil, err
}
return newInvoices, nil
}
// LookupInvoice attempts to look up an invoice according to its 32 byte
// payment hash. If an invoice which can settle the HTLC identified by the
// passed payment hash isn't found, then an error is returned. Otherwise, the
// full invoice is returned. Before setting the incoming HTLC, the values
// SHOULD be checked to ensure the payer meets the agreed upon contractual
// terms of the payment.
func (d *DB) LookupInvoice(paymentHash [32]byte) (Invoice, error) {
var invoice Invoice
err := d.View(func(tx *bbolt.Tx) error {
invoices := tx.Bucket(invoiceBucket)
if invoices == nil {
return ErrNoInvoicesCreated
}
invoiceIndex := invoices.Bucket(invoiceIndexBucket)
if invoiceIndex == nil {
return ErrNoInvoicesCreated
}
// Check the invoice index to see if an invoice paying to this
// hash exists within the DB.
invoiceNum := invoiceIndex.Get(paymentHash[:])
if invoiceNum == nil {
return ErrInvoiceNotFound
}
// An invoice matching the payment hash has been found, so
// retrieve the record of the invoice itself.
i, err := fetchInvoice(invoiceNum, invoices)
if err != nil {
return err
}
invoice = i
return nil
})
if err != nil {
return invoice, err
}
return invoice, 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 := d.View(func(tx *bbolt.Tx) error {
invoiceB := tx.Bucket(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
}
// InvoiceQuery represents a query to the invoice database. The query allows a
// caller to retrieve all invoices starting from a particular add index and
// limit the number of results returned.
type InvoiceQuery struct {
// IndexOffset is the offset within the add indices to start at. This
// can be used to start the response at a particular invoice.
IndexOffset uint64
// NumMaxInvoices is the maximum number of invoices that should be
// starting from the add index.
NumMaxInvoices uint64
// PendingOnly, if set, returns unsettled invoices starting from the
// add index.
PendingOnly bool
// Reversed, if set, indicates that the invoices returned should start
// from the IndexOffset and go backwards.
Reversed bool
}
// InvoiceSlice is the response to a invoice query. It includes the original
// query, the set of invoices that match the query, and an integer which
// represents the offset index of the last item in the set of returned invoices.
// This integer allows callers to resume their query using this offset in the
// event that the query's response exceeds the maximum number of returnable
// invoices.
type InvoiceSlice struct {
InvoiceQuery
// Invoices is the set of invoices that matched the query above.
Invoices []Invoice
// FirstIndexOffset is the index of the first element in the set of
// returned Invoices above. Callers can use this to resume their query
// in the event that the slice has too many events to fit into a single
// response.
FirstIndexOffset uint64
// LastIndexOffset is the index of the last element in the set of
// returned Invoices above. Callers can use this to resume their query
// in the event that the slice has too many events to fit into a single
// response.
LastIndexOffset uint64
}
// QueryInvoices allows a caller to query the invoice database for invoices
// within the specified add index range.
func (d *DB) QueryInvoices(q InvoiceQuery) (InvoiceSlice, error) {
resp := InvoiceSlice{
InvoiceQuery: q,
}
err := d.View(func(tx *bbolt.Tx) error {
// If the bucket wasn't found, then there aren't any invoices
// within the database yet, so we can simply exit.
invoices := tx.Bucket(invoiceBucket)
if invoices == nil {
return ErrNoInvoicesCreated
}
invoiceAddIndex := invoices.Bucket(addIndexBucket)
if invoiceAddIndex == nil {
return ErrNoInvoicesCreated
}
// keyForIndex is a helper closure that retrieves the invoice
// key for the given add index of an invoice.
keyForIndex := func(c *bbolt.Cursor, index uint64) []byte {
var keyIndex [8]byte
byteOrder.PutUint64(keyIndex[:], index)
_, invoiceKey := c.Seek(keyIndex[:])
return invoiceKey
}
// nextKey is a helper closure to determine what the next
// invoice key is when iterating over the invoice add index.
nextKey := func(c *bbolt.Cursor) ([]byte, []byte) {
if q.Reversed {
return c.Prev()
}
return c.Next()
}
// We'll be using a cursor to seek into the database and return
// a slice of invoices. We'll need to determine where to start
// our cursor depending on the parameters set within the query.
c := invoiceAddIndex.Cursor()
invoiceKey := keyForIndex(c, q.IndexOffset+1)
// If the query is specifying reverse iteration, then we must
// handle a few offset cases.
if q.Reversed {
switch q.IndexOffset {
// This indicates the default case, where no offset was
// specified. In that case we just start from the last
// invoice.
case 0:
_, invoiceKey = c.Last()
// This indicates the offset being set to the very
// first invoice. Since there are no invoices before
// this offset, and the direction is reversed, we can
// return without adding any invoices to the response.
case 1:
return nil
// Otherwise we start iteration at the invoice prior to
// the offset.
default:
invoiceKey = keyForIndex(c, q.IndexOffset-1)
}
}
// If we know that a set of invoices exists, then we'll begin
// our seek through the bucket in order to satisfy the query.
// We'll continue until either we reach the end of the range, or
// reach our max number of invoices.
for ; invoiceKey != nil; _, invoiceKey = nextKey(c) {
// If our current return payload exceeds the max number
// of invoices, then we'll exit now.
if uint64(len(resp.Invoices)) >= q.NumMaxInvoices {
break
}
invoice, err := fetchInvoice(invoiceKey, invoices)
if err != nil {
return err
}
// Skip any settled invoices if the caller is only
// interested in unsettled.
if q.PendingOnly &&
invoice.Terms.State == ContractSettled {
continue
}
// At this point, we've exhausted the offset, so we'll
// begin collecting invoices found within the range.
resp.Invoices = append(resp.Invoices, invoice)
}
// If we iterated through the add index in reverse order, then
// we'll need to reverse the slice of invoices to return them in
// forward order.
if q.Reversed {
numInvoices := len(resp.Invoices)
for i := 0; i < numInvoices/2; i++ {
opposite := numInvoices - i - 1
resp.Invoices[i], resp.Invoices[opposite] =
resp.Invoices[opposite], resp.Invoices[i]
}
}
return nil
})
if err != nil && err != ErrNoInvoicesCreated {
return resp, err
}
// Finally, record the indexes of the first and last invoices returned
// so that the caller can resume from this point later on.
if len(resp.Invoices) > 0 {
resp.FirstIndexOffset = resp.Invoices[0].AddIndex
resp.LastIndexOffset = resp.Invoices[len(resp.Invoices)-1].AddIndex
}
return resp, nil
}
// UpdateInvoice attempts to update an invoice corresponding to the passed
// payment hash. If an invoice matching the passed payment hash doesn't exist
// within the database, then the action will fail with a "not found" error.
//
// The update is performed inside the same database transaction that fetches the
// invoice and is therefore atomic. The fields to update are controlled by the
// supplied callback.
func (d *DB) UpdateInvoice(paymentHash lntypes.Hash,
callback InvoiceUpdateCallback) (*Invoice, error) {
var updatedInvoice *Invoice
err := d.Update(func(tx *bbolt.Tx) error {
invoices, err := tx.CreateBucketIfNotExists(invoiceBucket)
if err != nil {
return err
}
invoiceIndex, err := invoices.CreateBucketIfNotExists(
invoiceIndexBucket,
)
if err != nil {
return err
}
settleIndex, err := invoices.CreateBucketIfNotExists(
settleIndexBucket,
)
if err != nil {
return err
}
// Check the invoice index to see if an invoice paying to this
// hash exists within the DB.
invoiceNum := invoiceIndex.Get(paymentHash[:])
if invoiceNum == nil {
return ErrInvoiceNotFound
}
updatedInvoice, err = d.updateInvoice(
paymentHash, invoices, settleIndex, invoiceNum,
callback,
)
return err
})
return updatedInvoice, err
}
// InvoicesSettledSince can be used by callers to catch up any settled invoices
// they missed within the settled invoice time series. We'll return all known
// settled invoice that have a settle index higher than the passed
// sinceSettleIndex.
//
// NOTE: The index starts from 1, as a result. We enforce that specifying a
// value below the starting index value is a noop.
func (d *DB) InvoicesSettledSince(sinceSettleIndex uint64) ([]Invoice, error) {
var settledInvoices []Invoice
// If an index of zero was specified, then in order to maintain
// backwards compat, we won't send out any new invoices.
if sinceSettleIndex == 0 {
return settledInvoices, nil
}
var startIndex [8]byte
byteOrder.PutUint64(startIndex[:], sinceSettleIndex)
err := d.DB.View(func(tx *bbolt.Tx) error {
invoices := tx.Bucket(invoiceBucket)
if invoices == nil {
return ErrNoInvoicesCreated
}
settleIndex := invoices.Bucket(settleIndexBucket)
if settleIndex == nil {
return ErrNoInvoicesCreated
}
// We'll now run through each entry in the add index starting
// at our starting index. We'll continue until we reach the
// very end of the current key space.
invoiceCursor := settleIndex.Cursor()
// We'll seek to the starting index, then manually advance the
// cursor in order to skip the entry with the since add index.
invoiceCursor.Seek(startIndex[:])
seqNo, invoiceKey := invoiceCursor.Next()
for ; seqNo != nil && bytes.Compare(seqNo, startIndex[:]) > 0; seqNo, invoiceKey = invoiceCursor.Next() {
// For each key found, we'll look up the actual
// invoice, then accumulate it into our return value.
invoice, err := fetchInvoice(invoiceKey, invoices)
if err != nil {
return err
}
settledInvoices = append(settledInvoices, invoice)
}
return nil
})
if err != nil {
return nil, err
}
return settledInvoices, nil
}
func putInvoice(invoices, invoiceIndex, addIndex *bbolt.Bucket,
i *Invoice, invoiceNum uint32, paymentHash lntypes.Hash) (
uint64, error) {
// Create the invoice key which is just the big-endian representation
// of the invoice number.
var invoiceKey [4]byte
byteOrder.PutUint32(invoiceKey[:], invoiceNum)
// Increment the num invoice counter index so the next invoice bares
// the proper ID.
var scratch [4]byte
invoiceCounter := invoiceNum + 1
byteOrder.PutUint32(scratch[:], invoiceCounter)
if err := invoiceIndex.Put(numInvoicesKey, scratch[:]); err != nil {
return 0, err
}
// Add the payment hash to the invoice index. This will let us quickly
// identify if we can settle an incoming payment, and also to possibly
// allow a single invoice to have multiple payment installations.
err := invoiceIndex.Put(paymentHash[:], invoiceKey[:])
if err != nil {
return 0, err
}
// Next, we'll obtain the next add invoice index (sequence
// number), so we can properly place this invoice within this
// event stream.
nextAddSeqNo, err := addIndex.NextSequence()
if err != nil {
return 0, err
}
// With the next sequence obtained, we'll updating the event series in
// the add index bucket to map this current add counter to the index of
// this new invoice.
var seqNoBytes [8]byte
byteOrder.PutUint64(seqNoBytes[:], nextAddSeqNo)
if err := addIndex.Put(seqNoBytes[:], invoiceKey[:]); err != nil {
return 0, err
}
i.AddIndex = nextAddSeqNo
// Finally, serialize the invoice itself to be written to the disk.
var buf bytes.Buffer
if err := serializeInvoice(&buf, i); err != nil {
return 0, err
}
if err := invoices.Put(invoiceKey[:], buf.Bytes()); err != nil {
return 0, err
}
return nextAddSeqNo, 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 fetchInvoice(invoiceNum []byte, invoices *bbolt.Bucket) (Invoice, error) {
invoiceBytes := invoices.Get(invoiceNum)
if invoiceBytes == nil {
return Invoice{}, ErrInvoiceNotFound
}
invoiceReader := bytes.NewReader(invoiceBytes)
return deserializeInvoice(invoiceReader)
}
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
}
// copySlice allocates a new slice and copies the source into it.
func copySlice(src []byte) []byte {
dest := make([]byte, len(src))
copy(dest, src)
return dest
}
// copyInvoice makes a deep copy of the supplied invoice.
func copyInvoice(src *Invoice) *Invoice {
dest := Invoice{
Memo: copySlice(src.Memo),
Receipt: copySlice(src.Receipt),
PaymentRequest: copySlice(src.PaymentRequest),
FinalCltvDelta: src.FinalCltvDelta,
CreationDate: src.CreationDate,
SettleDate: src.SettleDate,
Terms: src.Terms,
AddIndex: src.AddIndex,
SettleIndex: src.SettleIndex,
AmtPaid: src.AmtPaid,
Htlcs: make(
map[CircuitKey]*InvoiceHTLC, len(src.Htlcs),
),
}
for k, v := range src.Htlcs {
dest.Htlcs[k] = v
}
return &dest
}
// updateInvoice fetches the invoice, obtains the update descriptor from the
// callback and applies the updates in a single db transaction.
func (d *DB) updateInvoice(hash lntypes.Hash, invoices, settleIndex *bbolt.Bucket,
invoiceNum []byte, callback InvoiceUpdateCallback) (*Invoice, error) {
invoice, err := fetchInvoice(invoiceNum, invoices)
if err != nil {
return nil, err
}
preUpdateState := invoice.Terms.State
// Create deep copy to prevent any accidental modification in the
// callback.
copy := copyInvoice(&invoice)
// Call the callback and obtain the update descriptor.
update, err := callback(copy)
if err != nil {
return &invoice, err
}
// Update invoice state.
invoice.Terms.State = update.State
now := d.now()
// Update htlc set.
for key, htlcUpdate := range update.Htlcs {
htlc, ok := invoice.Htlcs[key]
// No update means the htlc needs to be cancelled.
if htlcUpdate == nil {
if !ok {
return nil, fmt.Errorf("unknown htlc %v", key)
}
if htlc.State == HtlcStateSettled {
return nil, fmt.Errorf("cannot cancel a " +
"settled htlc")
}
htlc.State = HtlcStateCancelled
htlc.ResolveTime = now
invoice.AmtPaid -= htlc.Amt
continue
}
// Add new htlc paying to the invoice.
if ok {
return nil, fmt.Errorf("htlc %v already exists", key)
}
htlc = &InvoiceHTLC{
Amt: htlcUpdate.Amt,
Expiry: htlcUpdate.Expiry,
AcceptHeight: uint32(htlcUpdate.AcceptHeight),
AcceptTime: now,
}
if preUpdateState == ContractSettled {
htlc.State = HtlcStateSettled
htlc.ResolveTime = now
} else {
htlc.State = HtlcStateAccepted
}
invoice.Htlcs[key] = htlc
invoice.AmtPaid += htlc.Amt
}
// If invoice moved to the settled state, update settle index and settle
// time.
if preUpdateState != invoice.Terms.State &&
invoice.Terms.State == ContractSettled {
if update.Preimage.Hash() != hash {
return nil, fmt.Errorf("preimage does not match")
}
invoice.Terms.PaymentPreimage = update.Preimage
// Settle all accepted htlcs.
for _, htlc := range invoice.Htlcs {
if htlc.State != HtlcStateAccepted {
continue
}
htlc.State = HtlcStateSettled
htlc.ResolveTime = now
}
err := setSettleFields(settleIndex, invoiceNum, &invoice, now)
if err != nil {
return nil, err
}
}
var buf bytes.Buffer
if err := serializeInvoice(&buf, &invoice); err != nil {
return nil, err
}
if err := invoices.Put(invoiceNum[:], buf.Bytes()); err != nil {
return nil, err
}
return &invoice, nil
}
func setSettleFields(settleIndex *bbolt.Bucket, invoiceNum []byte,
invoice *Invoice, now time.Time) error {
// Now that we know the invoice hasn't already been settled, we'll
// update the settle index so we can place this settle event in the
// proper location within our time series.
nextSettleSeqNo, err := settleIndex.NextSequence()
if err != nil {
return err
}
var seqNoBytes [8]byte
byteOrder.PutUint64(seqNoBytes[:], nextSettleSeqNo)
if err := settleIndex.Put(seqNoBytes[:], invoiceNum); err != nil {
return err
}
invoice.Terms.State = ContractSettled
invoice.SettleDate = now
invoice.SettleIndex = nextSettleSeqNo
return nil
}