mirror of https://github.com/lightninglabs/loop
instantout: add fsm and actions
sputn1ck
3 months ago
parent
89b5c00cfa
commit
56ed6f7ccb
@ -0,0 +1,615 @@
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package instantout
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import (
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"context"
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"crypto/rand"
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"errors"
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"fmt"
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"time"
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"github.com/btcsuite/btcd/btcec/v2"
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"github.com/btcsuite/btcd/btcutil"
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"github.com/btcsuite/btcd/txscript"
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"github.com/lightninglabs/lndclient"
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"github.com/lightninglabs/loop/fsm"
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"github.com/lightninglabs/loop/instantout/reservation"
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"github.com/lightninglabs/loop/loopdb"
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"github.com/lightninglabs/loop/swap"
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loop_rpc "github.com/lightninglabs/loop/swapserverrpc"
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"github.com/lightningnetwork/lnd/lnrpc"
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"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
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"github.com/lightningnetwork/lnd/lntypes"
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)
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var (
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// Define route independent max routing fees. We have currently no way
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// to get a reliable estimate of the routing fees. Best we can do is
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// the minimum routing fees, which is not very indicative.
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maxRoutingFeeBase = btcutil.Amount(10)
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maxRoutingFeeRate = int64(20000)
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// urgentConfTarget is the target number of blocks for the htlc to be
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// confirmed quickly.
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urgentConfTarget = int32(3)
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// normalConfTarget is the target number of blocks for the sweepless
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// sweep to be confirmed.
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normalConfTarget = int32(6)
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// defaultMaxParts is the default maximum number of parts for the swap.
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defaultMaxParts = uint32(5)
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// defaultSendpaymentTimeout is the default timeout for the swap invoice.
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defaultSendpaymentTimeout = time.Minute * 5
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// defaultPollPaymentTime is the default time to poll the server for the
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// payment status.
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defaultPollPaymentTime = time.Second * 15
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)
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// InitInstantOutCtx contains the context for the InitInstantOutAction.
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type InitInstantOutCtx struct {
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cltvExpiry int32
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reservations []reservation.ID
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initationHeight int32
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outgoingChanSet loopdb.ChannelSet
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protocolVersion ProtocolVersion
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}
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// InitInstantOutAction is the first action that is executed when the instant
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// out FSM is started. It will send the instant out request to the server.
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func (f *FSM) InitInstantOutAction(eventCtx fsm.EventContext) fsm.EventType {
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initCtx, ok := eventCtx.(*InitInstantOutCtx)
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if !ok {
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return f.HandleError(fsm.ErrInvalidContextType)
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}
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if len(initCtx.reservations) == 0 {
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return f.HandleError(fmt.Errorf("no reservations provided"))
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}
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var (
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reservationAmt uint64
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reservationIds = make([][]byte, 0, len(initCtx.reservations))
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reservations = make(
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[]*reservation.Reservation, 0, len(initCtx.reservations),
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)
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)
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// The requested amount needs to be full reservation amounts.
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for _, reservationId := range initCtx.reservations {
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resId := reservationId
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res, err := f.cfg.ReservationManager.GetReservation(
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f.ctx, resId,
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)
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if err != nil {
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return f.HandleError(err)
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}
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// Check if the reservation is locked.
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if res.State == reservation.Locked {
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return f.HandleError(fmt.Errorf("reservation %v is "+
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"locked", reservationId))
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}
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reservationAmt += uint64(res.Value)
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reservationIds = append(reservationIds, resId[:])
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reservations = append(reservations, res)
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}
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// Create the preimage for the swap.
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var preimage lntypes.Preimage
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if _, err := rand.Read(preimage[:]); err != nil {
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return f.HandleError(err)
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}
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// Create the keys for the swap.
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keyRes, err := f.cfg.Wallet.DeriveNextKey(f.ctx, KeyFamily)
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if err != nil {
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return f.HandleError(err)
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}
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swapHash := preimage.Hash()
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// Create a high fee rate so that the htlc will be confirmed quickly.
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feeRate, err := f.cfg.Wallet.EstimateFeeRate(f.ctx, urgentConfTarget)
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if err != nil {
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f.Infof("error estimating fee rate: %v", err)
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return f.HandleError(err)
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}
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// Send the instantout request to the server.
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instantOutResponse, err := f.cfg.InstantOutClient.RequestInstantLoopOut(
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f.ctx,
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&loop_rpc.InstantLoopOutRequest{
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ReceiverKey: keyRes.PubKey.SerializeCompressed(),
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SwapHash: swapHash[:],
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Expiry: initCtx.cltvExpiry,
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HtlcFeeRate: uint64(feeRate),
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ReservationIds: reservationIds,
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ProtocolVersion: CurrentRpcProtocolVersion(),
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},
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)
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if err != nil {
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return f.HandleError(err)
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}
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// Decode the invoice to check if the hash is valid.
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payReq, err := f.cfg.LndClient.DecodePaymentRequest(
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f.ctx, instantOutResponse.SwapInvoice,
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)
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if err != nil {
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return f.HandleError(err)
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}
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if swapHash != payReq.Hash {
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return f.HandleError(fmt.Errorf("invalid swap invoice hash: "+
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"expected %x got %x", preimage.Hash(), payReq.Hash))
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}
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serverPubkey, err := btcec.ParsePubKey(instantOutResponse.SenderKey)
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if err != nil {
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return f.HandleError(err)
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}
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// Create the address that we'll send the funds to.
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sweepAddress, err := f.cfg.Wallet.NextAddr(
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f.ctx, "", walletrpc.AddressType_TAPROOT_PUBKEY, false,
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)
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if err != nil {
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return f.HandleError(err)
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}
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// Now we can create the instant out.
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instantOut := &InstantOut{
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SwapHash: swapHash,
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swapPreimage: preimage,
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protocolVersion: ProtocolVersionFullReservation,
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initiationHeight: initCtx.initationHeight,
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outgoingChanSet: initCtx.outgoingChanSet,
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cltvExpiry: initCtx.cltvExpiry,
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clientPubkey: keyRes.PubKey,
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serverPubkey: serverPubkey,
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value: btcutil.Amount(reservationAmt),
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htlcFeeRate: feeRate,
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swapInvoice: instantOutResponse.SwapInvoice,
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reservations: reservations,
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keyLocator: keyRes.KeyLocator,
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sweepAddress: sweepAddress,
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}
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err = f.cfg.Store.CreateInstantLoopOut(f.ctx, instantOut)
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if err != nil {
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return f.HandleError(err)
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}
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f.InstantOut = instantOut
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return OnInit
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}
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// PollPaymentAcceptedAction locks the reservations, sends the payment to the
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// server and polls the server for the payment status.
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func (f *FSM) PollPaymentAcceptedAction(_ fsm.EventContext) fsm.EventType {
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// Now that we're doing the swap, we first lock the reservations
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// so that they can't be used for other swaps.
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for _, reservation := range f.InstantOut.reservations {
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err := f.cfg.ReservationManager.LockReservation(
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f.ctx, reservation.ID,
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)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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}
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// Now we send the payment to the server.
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payChan, paymentErrChan, err := f.cfg.RouterClient.SendPayment(
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f.ctx,
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lndclient.SendPaymentRequest{
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Invoice: f.InstantOut.swapInvoice,
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Timeout: defaultSendpaymentTimeout,
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MaxParts: defaultMaxParts,
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MaxFee: getMaxRoutingFee(f.InstantOut.value),
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},
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)
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if err != nil {
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f.Errorf("error sending payment: %v", err)
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return f.handleErrorAndUnlockReservations(err)
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}
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// We'll continuously poll the server for the payment status.
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pollPaymentTries := 0
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// We want to poll quickly the first time.
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timer := time.NewTimer(time.Second)
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for {
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select {
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case payRes := <-payChan:
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f.Debugf("payment result: %v", payRes)
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if payRes.State == lnrpc.Payment_FAILED {
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return f.handleErrorAndUnlockReservations(
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fmt.Errorf("payment failed: %v",
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payRes.FailureReason),
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)
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}
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case err := <-paymentErrChan:
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f.Errorf("error sending payment: %v", err)
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return f.handleErrorAndUnlockReservations(err)
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case <-f.ctx.Done():
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return f.handleErrorAndUnlockReservations(nil)
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case <-timer.C:
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res, err := f.cfg.InstantOutClient.PollPaymentAccepted(
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f.ctx, &loop_rpc.PollPaymentAcceptedRequest{
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SwapHash: f.InstantOut.SwapHash[:],
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},
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)
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if err != nil {
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pollPaymentTries++
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if pollPaymentTries > 20 {
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return f.handleErrorAndUnlockReservations(err)
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}
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}
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if res != nil && res.Accepted {
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return OnPaymentAccepted
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}
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timer.Reset(defaultPollPaymentTime)
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}
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}
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}
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// BuildHTLCAction creates the htlc transaction, exchanges nonces with
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// the server and sends the htlc signatures to the server.
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func (f *FSM) BuildHTLCAction(eventCtx fsm.EventContext) fsm.EventType {
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htlcSessions, htlcClientNonces, err := f.InstantOut.createMusig2Session(
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f.ctx, f.cfg.Signer,
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)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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f.htlcMusig2Sessions = htlcSessions
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// Send the server the client nonces.
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htlcInitRes, err := f.cfg.InstantOutClient.InitHtlcSig(
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f.ctx,
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&loop_rpc.InitHtlcSigRequest{
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SwapHash: f.InstantOut.SwapHash[:],
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HtlcClientNonces: htlcClientNonces,
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},
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)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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if len(htlcInitRes.HtlcServerNonces) != len(f.InstantOut.reservations) {
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return f.handleErrorAndUnlockReservations(
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errors.New("invalid number of server nonces"),
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)
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}
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htlcServerNonces, err := toNonces(htlcInitRes.HtlcServerNonces)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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// Now that our nonces are set, we can create and sign the htlc
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// transaction.
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htlcTx, err := f.InstantOut.createHtlcTransaction(f.cfg.Network)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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// Next we'll get our sweep tx signatures.
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htlcSigs, err := f.InstantOut.signMusig2Tx(
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f.ctx, f.cfg.Signer, htlcTx, f.htlcMusig2Sessions,
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htlcServerNonces,
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)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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// Send the server the htlc signatures.
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htlcRes, err := f.cfg.InstantOutClient.PushHtlcSig(
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f.ctx,
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&loop_rpc.PushHtlcSigRequest{
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SwapHash: f.InstantOut.SwapHash[:],
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ClientSigs: htlcSigs,
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},
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)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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// We can now finalize the htlc transaction.
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htlcTx, err = f.InstantOut.finalizeMusig2Transaction(
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f.ctx, f.cfg.Signer, f.htlcMusig2Sessions, htlcTx,
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htlcRes.ServerSigs,
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)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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f.InstantOut.finalizedHtlcTx = htlcTx
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return OnHtlcSigReceived
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}
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// PushPreimageAction pushes the preimage to the server. It also creates the
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// sweepless sweep transaction and sends the signatures to the server. Finally,
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// it publishes the sweepless sweep transaction. If any of the steps after
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// pushing the preimage fail, the htlc timeout transaction will be published.
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func (f *FSM) PushPreimageAction(eventCtx fsm.EventContext) fsm.EventType {
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// First we'll create the musig2 context.
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coopSessions, coopClientNonces, err := f.InstantOut.createMusig2Session(
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f.ctx, f.cfg.Signer,
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)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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f.sweeplessSweepSessions = coopSessions
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// Get the feerate for the coop sweep.
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feeRate, err := f.cfg.Wallet.EstimateFeeRate(f.ctx, normalConfTarget)
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if err != nil {
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return f.handleErrorAndUnlockReservations(err)
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}
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pushPreImageRes, err := f.cfg.InstantOutClient.PushPreimage(
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f.ctx,
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&loop_rpc.PushPreimageRequest{
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Preimage: f.InstantOut.swapPreimage[:],
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ClientNonces: coopClientNonces,
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ClientSweepAddr: f.InstantOut.sweepAddress.String(),
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MusigTxFeeRate: uint64(feeRate),
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},
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)
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// Now that we have revealed the preimage, if any following step fail,
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// we'll need to publish the htlc tx.
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if err != nil {
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f.LastActionError = err
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return OnErrorPublishHtlc
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}
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// Now that we have the sweepless sweep signatures we can build and
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// publish the sweepless sweep transaction.
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sweepTx, err := f.InstantOut.createSweeplessSweepTx(feeRate)
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if err != nil {
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f.LastActionError = err
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return OnErrorPublishHtlc
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}
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coopServerNonces, err := toNonces(pushPreImageRes.ServerNonces)
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if err != nil {
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f.LastActionError = err
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return OnErrorPublishHtlc
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}
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// Next we'll get our sweep tx signatures.
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_, err = f.InstantOut.signMusig2Tx(
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f.ctx, f.cfg.Signer, sweepTx, f.sweeplessSweepSessions,
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coopServerNonces,
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)
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if err != nil {
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f.LastActionError = err
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return OnErrorPublishHtlc
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}
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// Now we'll finalize the sweepless sweep transaction.
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sweepTx, err = f.InstantOut.finalizeMusig2Transaction(
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f.ctx, f.cfg.Signer, f.sweeplessSweepSessions, sweepTx,
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pushPreImageRes.Musig2SweepSigs,
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)
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if err != nil {
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f.LastActionError = err
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return OnErrorPublishHtlc
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}
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txLabel := fmt.Sprintf("sweepless-sweep-%v",
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f.InstantOut.swapPreimage.Hash())
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// Publish the sweepless sweep transaction.
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err = f.cfg.Wallet.PublishTransaction(f.ctx, sweepTx, txLabel)
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if err != nil {
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f.LastActionError = err
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return OnErrorPublishHtlc
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}
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f.InstantOut.finalizedSweeplessSweepTx = sweepTx
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txHash := f.InstantOut.finalizedSweeplessSweepTx.TxHash()
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f.InstantOut.SweepTxHash = &txHash
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return OnSweeplessSweepPublished
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}
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// WaitForSweeplessSweepConfirmedAction waits for the sweepless sweep
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// transaction to be confirmed.
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func (f *FSM) WaitForSweeplessSweepConfirmedAction(
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eventCtx fsm.EventContext) fsm.EventType {
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pkscript, err := txscript.PayToAddrScript(f.InstantOut.sweepAddress)
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if err != nil {
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return f.HandleError(err)
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}
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confChan, confErrChan, err := f.cfg.ChainNotifier.
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RegisterConfirmationsNtfn(
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f.ctx, f.InstantOut.SweepTxHash, pkscript,
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1, f.InstantOut.initiationHeight,
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)
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if err != nil {
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return f.HandleError(err)
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}
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for {
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select {
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case spendErr := <-confErrChan:
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f.LastActionError = spendErr
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f.Errorf("error listening for sweepless sweep "+
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"confirmation: %v", spendErr)
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return OnErrorPublishHtlc
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case conf := <-confChan:
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f.InstantOut.
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sweepConfirmationHeight = conf.BlockHeight
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return OnSweeplessSweepConfirmed
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}
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}
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}
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// PublishHtlcAction publishes the htlc transaction and the htlc sweep
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// transaction.
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func (f *FSM) PublishHtlcAction(eventCtx fsm.EventContext) fsm.EventType {
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// Publish the htlc transaction.
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err := f.cfg.Wallet.PublishTransaction(
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f.ctx, f.InstantOut.finalizedHtlcTx,
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fmt.Sprintf("htlc-%v", f.InstantOut.swapPreimage.Hash()),
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)
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if err != nil {
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return f.HandleError(err)
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}
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txHash := f.InstantOut.finalizedHtlcTx.TxHash()
|
||||
f.Debugf("published htlc tx: %v", txHash)
|
||||
|
||||
// We'll now wait for the htlc to be confirmed.
|
||||
confChan, confErrChan, err := f.cfg.ChainNotifier.
|
||||
RegisterConfirmationsNtfn(
|
||||
f.ctx, &txHash,
|
||||
f.InstantOut.finalizedHtlcTx.TxOut[0].PkScript,
|
||||
1, f.InstantOut.initiationHeight,
|
||||
)
|
||||
if err != nil {
|
||||
return f.HandleError(err)
|
||||
}
|
||||
for {
|
||||
select {
|
||||
case spendErr := <-confErrChan:
|
||||
return f.HandleError(spendErr)
|
||||
|
||||
case <-confChan:
|
||||
return OnHtlcPublished
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// PublishHtlcSweepAction publishes the htlc sweep transaction.
|
||||
func (f *FSM) PublishHtlcSweepAction(eventCtx fsm.EventContext) fsm.EventType {
|
||||
// Create a feerate that will confirm the htlc quickly.
|
||||
feeRate, err := f.cfg.Wallet.EstimateFeeRate(f.ctx, urgentConfTarget)
|
||||
if err != nil {
|
||||
return f.HandleError(err)
|
||||
}
|
||||
|
||||
getInfo, err := f.cfg.LndClient.GetInfo(f.ctx)
|
||||
if err != nil {
|
||||
return f.HandleError(err)
|
||||
}
|
||||
|
||||
// We can immediately publish the htlc sweep transaction.
|
||||
htlcSweepTx, err := f.InstantOut.generateHtlcSweepTx(
|
||||
f.ctx, f.cfg.Signer, feeRate, f.cfg.Network, getInfo.BlockHeight,
|
||||
)
|
||||
if err != nil {
|
||||
return f.HandleError(err)
|
||||
}
|
||||
|
||||
label := fmt.Sprintf("htlc-sweep-%v", f.InstantOut.swapPreimage.Hash())
|
||||
|
||||
err = f.cfg.Wallet.PublishTransaction(f.ctx, htlcSweepTx, label)
|
||||
if err != nil {
|
||||
log.Errorf("error publishing htlc sweep tx: %v", err)
|
||||
return f.HandleError(err)
|
||||
}
|
||||
|
||||
sweepTxHash := htlcSweepTx.TxHash()
|
||||
|
||||
f.InstantOut.SweepTxHash = &sweepTxHash
|
||||
|
||||
return OnHtlcSweepPublished
|
||||
}
|
||||
|
||||
// WaitForHtlcSweepConfirmedAction waits for the htlc sweep transaction to be
|
||||
// confirmed.
|
||||
func (f *FSM) WaitForHtlcSweepConfirmedAction(
|
||||
eventCtx fsm.EventContext) fsm.EventType {
|
||||
|
||||
sweepPkScript, err := txscript.PayToAddrScript(
|
||||
f.InstantOut.sweepAddress,
|
||||
)
|
||||
if err != nil {
|
||||
return f.HandleError(err)
|
||||
}
|
||||
|
||||
confChan, confErrChan, err := f.cfg.ChainNotifier.RegisterConfirmationsNtfn(
|
||||
f.ctx, f.InstantOut.SweepTxHash, sweepPkScript,
|
||||
1, f.InstantOut.initiationHeight,
|
||||
)
|
||||
if err != nil {
|
||||
return f.HandleError(err)
|
||||
}
|
||||
|
||||
f.Debugf("waiting for htlc sweep tx %v to be confirmed",
|
||||
f.InstantOut.SweepTxHash)
|
||||
|
||||
for {
|
||||
select {
|
||||
case spendErr := <-confErrChan:
|
||||
return f.HandleError(spendErr)
|
||||
|
||||
case conf := <-confChan:
|
||||
f.InstantOut.
|
||||
sweepConfirmationHeight = conf.BlockHeight
|
||||
|
||||
return OnHtlcSwept
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// handleErrorAndUnlockReservations handles an error and unlocks the
|
||||
// reservations.
|
||||
func (f *FSM) handleErrorAndUnlockReservations(err error) fsm.EventType {
|
||||
// We might get here from a canceled context, we create a new context
|
||||
// with a timeout to unlock the reservations.
|
||||
ctx, cancel := context.WithTimeout(context.Background(), time.Second*30)
|
||||
defer cancel()
|
||||
|
||||
// Unlock the reservations.
|
||||
for _, reservation := range f.InstantOut.reservations {
|
||||
err := f.cfg.ReservationManager.UnlockReservation(
|
||||
ctx, reservation.ID,
|
||||
)
|
||||
if err != nil {
|
||||
f.Errorf("error unlocking reservation: %v", err)
|
||||
return f.HandleError(err)
|
||||
}
|
||||
}
|
||||
|
||||
// We're also sending the server a cancel message so that it can
|
||||
// release the reservations. This can be done in a goroutine as we
|
||||
// wan't to fail the fsm early.
|
||||
go func() {
|
||||
ctx, cancel := context.WithTimeout(context.Background(), time.Second*30)
|
||||
defer cancel()
|
||||
_, cancelErr := f.cfg.InstantOutClient.CancelInstantSwap(
|
||||
ctx, &loop_rpc.CancelInstantSwapRequest{
|
||||
SwapHash: f.InstantOut.SwapHash[:],
|
||||
},
|
||||
)
|
||||
if cancelErr != nil {
|
||||
// We'll log the error but not return it as we want to return the
|
||||
// original error.
|
||||
f.Debugf("error sending cancel message: %v", cancelErr)
|
||||
}
|
||||
}()
|
||||
|
||||
return f.HandleError(err)
|
||||
}
|
||||
|
||||
func getMaxRoutingFee(amt btcutil.Amount) btcutil.Amount {
|
||||
return swap.CalcFee(amt, maxRoutingFeeBase, maxRoutingFeeRate)
|
||||
}
|
||||
@ -0,0 +1,401 @@
|
||||
package instantout
|
||||
|
||||
import (
|
||||
"context"
|
||||
"errors"
|
||||
|
||||
"github.com/btcsuite/btcd/chaincfg"
|
||||
"github.com/lightninglabs/lndclient"
|
||||
"github.com/lightninglabs/loop/fsm"
|
||||
loop_rpc "github.com/lightninglabs/loop/swapserverrpc"
|
||||
"github.com/lightningnetwork/lnd/input"
|
||||
)
|
||||
|
||||
type ProtocolVersion uint32
|
||||
|
||||
const (
|
||||
// ProtocolVersionUndefined is the undefined protocol version.
|
||||
ProtocolVersionUndefined ProtocolVersion = 0
|
||||
|
||||
// ProtocolVersionFullReservation is the protocol version that uses
|
||||
// the full reservation amount without change.
|
||||
ProtocolVersionFullReservation ProtocolVersion = 1
|
||||
)
|
||||
|
||||
// CurrentProtocolVersion returns the current protocol version.
|
||||
func CurrentProtocolVersion() ProtocolVersion {
|
||||
return ProtocolVersionFullReservation
|
||||
}
|
||||
|
||||
// CurrentRpcProtocolVersion returns the current rpc protocol version.
|
||||
func CurrentRpcProtocolVersion() loop_rpc.InstantOutProtocolVersion {
|
||||
return loop_rpc.InstantOutProtocolVersion(CurrentProtocolVersion())
|
||||
}
|
||||
|
||||
const (
|
||||
// defaultObserverSize is the size of the fsm observer channel.
|
||||
defaultObserverSize = 15
|
||||
)
|
||||
|
||||
var (
|
||||
ErrProtocolVersionNotSupported = errors.New(
|
||||
"protocol version not supported",
|
||||
)
|
||||
)
|
||||
|
||||
// States.
|
||||
var (
|
||||
// Init is the initial state of the instant out FSM.
|
||||
Init = fsm.StateType("Init")
|
||||
|
||||
// SendPaymentAndPollAccepted is the state where the payment is sent
|
||||
// and the server is polled for the accepted state.
|
||||
SendPaymentAndPollAccepted = fsm.StateType("SendPaymentAndPollAccepted")
|
||||
|
||||
// BuildHtlc is the state where the htlc transaction is built.
|
||||
BuildHtlc = fsm.StateType("BuildHtlc")
|
||||
|
||||
// PushPreimage is the state where the preimage is pushed to the server.
|
||||
PushPreimage = fsm.StateType("PushPreimage")
|
||||
|
||||
// WaitForSweeplessSweepConfirmed is the state where we wait for the
|
||||
// sweepless sweep to be confirmed.
|
||||
WaitForSweeplessSweepConfirmed = fsm.StateType(
|
||||
"WaitForSweeplessSweepConfirmed")
|
||||
|
||||
// FinishedSweeplessSweep is the state where the swap is finished by
|
||||
// publishing the sweepless sweep.
|
||||
FinishedSweeplessSweep = fsm.StateType("FinishedSweeplessSweep")
|
||||
|
||||
// PublishHtlc is the state where the htlc transaction is published.
|
||||
PublishHtlc = fsm.StateType("PublishHtlc")
|
||||
|
||||
// PublishHtlcSweep is the state where the htlc sweep transaction is
|
||||
// published.
|
||||
PublishHtlcSweep = fsm.StateType("PublishHtlcSweep")
|
||||
|
||||
// FinishedHtlcPreimageSweep is the state where the swap is finished by
|
||||
// publishing the htlc preimage sweep.
|
||||
FinishedHtlcPreimageSweep = fsm.StateType("FinishedHtlcPreimageSweep")
|
||||
|
||||
// WaitForHtlcSweepConfirmed is the state where we wait for the htlc
|
||||
// sweep to be confirmed.
|
||||
WaitForHtlcSweepConfirmed = fsm.StateType("WaitForHtlcSweepConfirmed")
|
||||
|
||||
// FailedHtlcSweep is the state where the htlc sweep failed.
|
||||
FailedHtlcSweep = fsm.StateType("FailedHtlcSweep")
|
||||
|
||||
// Failed is the state where the swap failed.
|
||||
Failed = fsm.StateType("InstantOutFailed")
|
||||
)
|
||||
|
||||
// Events.
|
||||
var (
|
||||
// OnStart is the event that is sent when the FSM is started.
|
||||
OnStart = fsm.EventType("OnStart")
|
||||
|
||||
// OnInit is the event that is triggered when the FSM is initialized.
|
||||
OnInit = fsm.EventType("OnInit")
|
||||
|
||||
// OnPaymentAccepted is the event that is triggered when the payment
|
||||
// is accepted by the server.
|
||||
OnPaymentAccepted = fsm.EventType("OnPaymentAccepted")
|
||||
|
||||
// OnHtlcSigReceived is the event that is triggered when the htlc sig
|
||||
// is received.
|
||||
OnHtlcSigReceived = fsm.EventType("OnHtlcSigReceived")
|
||||
|
||||
// OnPreimagePushed is the event that is triggered when the preimage
|
||||
// is pushed to the server.
|
||||
OnPreimagePushed = fsm.EventType("OnPreimagePushed")
|
||||
|
||||
// OnSweeplessSweepPublished is the event that is triggered when the
|
||||
// sweepless sweep is published.
|
||||
OnSweeplessSweepPublished = fsm.EventType("OnSweeplessSweepPublished")
|
||||
|
||||
// OnSweeplessSweepConfirmed is the event that is triggered when the
|
||||
// sweepless sweep is confirmed.
|
||||
OnSweeplessSweepConfirmed = fsm.EventType("OnSweeplessSweepConfirmed")
|
||||
|
||||
// OnErrorPublishHtlc is the event that is triggered when the htlc
|
||||
// sweep is published after an error.
|
||||
OnErrorPublishHtlc = fsm.EventType("OnErrorPublishHtlc")
|
||||
|
||||
// OnInvalidCoopSweep is the event that is triggered when the coop
|
||||
// sweep is invalid.
|
||||
OnInvalidCoopSweep = fsm.EventType("OnInvalidCoopSweep")
|
||||
|
||||
// OnHtlcPublished is the event that is triggered when the htlc
|
||||
// transaction is published.
|
||||
OnHtlcPublished = fsm.EventType("OnHtlcPublished")
|
||||
|
||||
// OnHtlcSweepPublished is the event that is triggered when the htlc
|
||||
// sweep is published.
|
||||
OnHtlcSweepPublished = fsm.EventType("OnHtlcSweepPublished")
|
||||
|
||||
// OnHtlcSwept is the event that is triggered when the htlc sweep is
|
||||
// confirmed.
|
||||
OnHtlcSwept = fsm.EventType("OnHtlcSwept")
|
||||
|
||||
// OnRecover is the event that is triggered when the FSM recovers from
|
||||
// a restart.
|
||||
OnRecover = fsm.EventType("OnRecover")
|
||||
)
|
||||
|
||||
// Config contains the services required for the instant out FSM.
|
||||
type Config struct {
|
||||
// Store is used to store the instant out.
|
||||
Store InstantLoopOutStore
|
||||
|
||||
// LndClient is used to decode the swap invoice.
|
||||
LndClient lndclient.LightningClient
|
||||
|
||||
// RouterClient is used to send the offchain payment to the server.
|
||||
RouterClient lndclient.RouterClient
|
||||
|
||||
// ChainNotifier is used to be notified of on-chain events.
|
||||
ChainNotifier lndclient.ChainNotifierClient
|
||||
|
||||
// Signer is used to sign transactions.
|
||||
Signer lndclient.SignerClient
|
||||
|
||||
// Wallet is used to derive keys.
|
||||
Wallet lndclient.WalletKitClient
|
||||
|
||||
// InstantOutClient is used to communicate with the swap server.
|
||||
InstantOutClient loop_rpc.InstantSwapServerClient
|
||||
|
||||
// ReservationManager is used to get the reservations and lock them.
|
||||
ReservationManager ReservationManager
|
||||
|
||||
// Network is the network that is used for the swap.
|
||||
Network *chaincfg.Params
|
||||
}
|
||||
|
||||
// FSM is the state machine that handles the instant out.
|
||||
type FSM struct {
|
||||
*fsm.StateMachine
|
||||
|
||||
ctx context.Context
|
||||
|
||||
// cfg contains all the services that the reservation manager needs to
|
||||
// operate.
|
||||
cfg *Config
|
||||
|
||||
// InstantOut contains all the information about the instant out.
|
||||
InstantOut *InstantOut
|
||||
|
||||
// htlcMusig2Sessions contains all the reservations input musig2
|
||||
// sessions that will be used for the htlc transaction.
|
||||
htlcMusig2Sessions []*input.MuSig2SessionInfo
|
||||
|
||||
// sweeplessSweepSessions contains all the reservations input musig2
|
||||
// sessions that will be used for the sweepless sweep transaction.
|
||||
sweeplessSweepSessions []*input.MuSig2SessionInfo
|
||||
}
|
||||
|
||||
// NewFSM creates a new instant out FSM.
|
||||
func NewFSM(ctx context.Context, cfg *Config,
|
||||
protocolVersion ProtocolVersion) (*FSM, error) {
|
||||
|
||||
instantOut := &InstantOut{
|
||||
State: fsm.EmptyState,
|
||||
protocolVersion: protocolVersion,
|
||||
}
|
||||
|
||||
return NewFSMFromInstantOut(ctx, cfg, instantOut)
|
||||
}
|
||||
|
||||
// NewFSMFromInstantOut creates a new instantout FSM from an existing instantout
|
||||
// recovered from the database.
|
||||
func NewFSMFromInstantOut(ctx context.Context, cfg *Config,
|
||||
instantOut *InstantOut) (*FSM, error) {
|
||||
|
||||
instantOutFSM := &FSM{
|
||||
ctx: ctx,
|
||||
cfg: cfg,
|
||||
InstantOut: instantOut,
|
||||
}
|
||||
switch instantOut.protocolVersion {
|
||||
case ProtocolVersionFullReservation:
|
||||
instantOutFSM.StateMachine = fsm.NewStateMachineWithState(
|
||||
instantOutFSM.GetV1ReservationStates(),
|
||||
instantOut.State, defaultObserverSize,
|
||||
)
|
||||
|
||||
default:
|
||||
return nil, ErrProtocolVersionNotSupported
|
||||
}
|
||||
|
||||
instantOutFSM.ActionEntryFunc = instantOutFSM.updateInstantOut
|
||||
|
||||
return instantOutFSM, nil
|
||||
}
|
||||
|
||||
// GetV1ReservationStates returns the states for the v1 reservation.
|
||||
func (f *FSM) GetV1ReservationStates() fsm.States {
|
||||
return fsm.States{
|
||||
fsm.EmptyState: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnStart: Init,
|
||||
},
|
||||
Action: nil,
|
||||
},
|
||||
Init: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnInit: SendPaymentAndPollAccepted,
|
||||
fsm.OnError: Failed,
|
||||
OnRecover: Failed,
|
||||
},
|
||||
Action: f.InitInstantOutAction,
|
||||
},
|
||||
SendPaymentAndPollAccepted: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnPaymentAccepted: BuildHtlc,
|
||||
fsm.OnError: Failed,
|
||||
OnRecover: Failed,
|
||||
},
|
||||
Action: f.PollPaymentAcceptedAction,
|
||||
},
|
||||
BuildHtlc: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnHtlcSigReceived: PushPreimage,
|
||||
fsm.OnError: Failed,
|
||||
OnRecover: Failed,
|
||||
},
|
||||
Action: f.BuildHTLCAction,
|
||||
},
|
||||
PushPreimage: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnSweeplessSweepPublished: WaitForSweeplessSweepConfirmed,
|
||||
fsm.OnError: Failed,
|
||||
OnErrorPublishHtlc: PublishHtlc,
|
||||
OnRecover: PushPreimage,
|
||||
},
|
||||
Action: f.PushPreimageAction,
|
||||
},
|
||||
WaitForSweeplessSweepConfirmed: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnSweeplessSweepConfirmed: FinishedSweeplessSweep,
|
||||
OnRecover: WaitForSweeplessSweepConfirmed,
|
||||
fsm.OnError: PublishHtlc,
|
||||
},
|
||||
Action: f.WaitForSweeplessSweepConfirmedAction,
|
||||
},
|
||||
FinishedSweeplessSweep: fsm.State{
|
||||
Transitions: fsm.Transitions{},
|
||||
Action: fsm.NoOpAction,
|
||||
},
|
||||
PublishHtlc: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
fsm.OnError: FailedHtlcSweep,
|
||||
OnRecover: PublishHtlc,
|
||||
OnHtlcPublished: PublishHtlcSweep,
|
||||
},
|
||||
Action: f.PublishHtlcAction,
|
||||
},
|
||||
PublishHtlcSweep: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnHtlcSweepPublished: WaitForHtlcSweepConfirmed,
|
||||
OnRecover: PublishHtlcSweep,
|
||||
fsm.OnError: FailedHtlcSweep,
|
||||
},
|
||||
Action: f.PublishHtlcSweepAction,
|
||||
},
|
||||
WaitForHtlcSweepConfirmed: fsm.State{
|
||||
Transitions: fsm.Transitions{
|
||||
OnHtlcSwept: FinishedHtlcPreimageSweep,
|
||||
OnRecover: WaitForHtlcSweepConfirmed,
|
||||
fsm.OnError: FailedHtlcSweep,
|
||||
},
|
||||
Action: f.WaitForHtlcSweepConfirmedAction,
|
||||
},
|
||||
FinishedHtlcPreimageSweep: fsm.State{
|
||||
Transitions: fsm.Transitions{},
|
||||
Action: fsm.NoOpAction,
|
||||
},
|
||||
FailedHtlcSweep: fsm.State{
|
||||
Action: fsm.NoOpAction,
|
||||
Transitions: fsm.Transitions{
|
||||
OnRecover: PublishHtlcSweep,
|
||||
},
|
||||
},
|
||||
Failed: fsm.State{
|
||||
Action: fsm.NoOpAction,
|
||||
},
|
||||
}
|
||||
}
|
||||
|
||||
// updateInstantOut is called after every action and updates the reservation
|
||||
// in the db.
|
||||
func (f *FSM) updateInstantOut(notification fsm.Notification) {
|
||||
f.Infof("Previous: %v, Event: %v, Next: %v", notification.PreviousState,
|
||||
notification.Event, notification.NextState)
|
||||
|
||||
// Skip the update if the reservation is not yet initialized.
|
||||
if f.InstantOut == nil {
|
||||
return
|
||||
}
|
||||
|
||||
f.InstantOut.State = notification.NextState
|
||||
|
||||
// If we're in the early stages we don't have created the reservation
|
||||
// in the store yet and won't need to update it.
|
||||
if f.InstantOut.State == Init ||
|
||||
f.InstantOut.State == fsm.EmptyState ||
|
||||
(notification.PreviousState == Init &&
|
||||
f.InstantOut.State == Failed) {
|
||||
|
||||
return
|
||||
}
|
||||
|
||||
err := f.cfg.Store.UpdateInstantLoopOut(f.ctx, f.InstantOut)
|
||||
if err != nil {
|
||||
log.Errorf("Error updating instant out: %v", err)
|
||||
return
|
||||
}
|
||||
}
|
||||
|
||||
// Infof logs an info message with the reservation hash as prefix.
|
||||
func (f *FSM) Infof(format string, args ...interface{}) {
|
||||
log.Infof(
|
||||
"InstantOut %v: "+format,
|
||||
append(
|
||||
[]interface{}{f.InstantOut.swapPreimage.Hash()},
|
||||
args...,
|
||||
)...,
|
||||
)
|
||||
}
|
||||
|
||||
// Debugf logs a debug message with the reservation hash as prefix.
|
||||
func (f *FSM) Debugf(format string, args ...interface{}) {
|
||||
log.Debugf(
|
||||
"InstantOut %v: "+format,
|
||||
append(
|
||||
[]interface{}{f.InstantOut.swapPreimage.Hash()},
|
||||
args...,
|
||||
)...,
|
||||
)
|
||||
}
|
||||
|
||||
// Errorf logs an error message with the reservation hash as prefix.
|
||||
func (f *FSM) Errorf(format string, args ...interface{}) {
|
||||
log.Errorf(
|
||||
"InstantOut %v: "+format,
|
||||
append(
|
||||
[]interface{}{f.InstantOut.swapPreimage.Hash()},
|
||||
args...,
|
||||
)...,
|
||||
)
|
||||
}
|
||||
|
||||
// isFinalState returns true if the state is a final state.
|
||||
func isFinalState(state fsm.StateType) bool {
|
||||
switch state {
|
||||
case Failed, FinishedHtlcPreimageSweep,
|
||||
FinishedSweeplessSweep:
|
||||
|
||||
return true
|
||||
}
|
||||
return false
|
||||
}
|
||||
@ -0,0 +1,488 @@
|
||||
package instantout
|
||||
|
||||
import (
|
||||
"context"
|
||||
"errors"
|
||||
"fmt"
|
||||
"reflect"
|
||||
|
||||
"github.com/btcsuite/btcd/btcec/v2"
|
||||
"github.com/btcsuite/btcd/btcec/v2/schnorr/musig2"
|
||||
"github.com/btcsuite/btcd/btcutil"
|
||||
"github.com/btcsuite/btcd/chaincfg"
|
||||
"github.com/btcsuite/btcd/chaincfg/chainhash"
|
||||
"github.com/btcsuite/btcd/txscript"
|
||||
"github.com/btcsuite/btcd/wire"
|
||||
"github.com/lightninglabs/lndclient"
|
||||
"github.com/lightninglabs/loop/fsm"
|
||||
"github.com/lightninglabs/loop/instantout/reservation"
|
||||
"github.com/lightninglabs/loop/loopdb"
|
||||
"github.com/lightninglabs/loop/swap"
|
||||
"github.com/lightningnetwork/lnd/input"
|
||||
"github.com/lightningnetwork/lnd/keychain"
|
||||
"github.com/lightningnetwork/lnd/lntypes"
|
||||
"github.com/lightningnetwork/lnd/lnwallet/chainfee"
|
||||
)
|
||||
|
||||
// InstantOut holds the necessary information to execute an instant out swap.
|
||||
type InstantOut struct {
|
||||
// SwapHash is the hash of the swap.
|
||||
SwapHash lntypes.Hash
|
||||
|
||||
// swapPreimage is the preimage that is used for the swap.
|
||||
swapPreimage lntypes.Preimage
|
||||
|
||||
// State is the current state of the swap.
|
||||
State fsm.StateType
|
||||
|
||||
// cltvExpiry is the expiry of the swap.
|
||||
cltvExpiry int32
|
||||
|
||||
// outgoingChanSet optionally specifies the short channel ids of the
|
||||
// channels that may be used to loop out.
|
||||
outgoingChanSet loopdb.ChannelSet
|
||||
|
||||
// reservations are the reservations that are used in as inputs for the
|
||||
// instant out swap.
|
||||
reservations []*reservation.Reservation
|
||||
|
||||
// protocolVersion is the version of the protocol that is used for the
|
||||
// swap.
|
||||
protocolVersion ProtocolVersion
|
||||
|
||||
// initiationHeight is the height at which the swap was initiated.
|
||||
initiationHeight int32
|
||||
|
||||
// value is the amount that is swapped.
|
||||
value btcutil.Amount
|
||||
|
||||
// keyLocator is the key locator that is used for the swap.
|
||||
keyLocator keychain.KeyLocator
|
||||
|
||||
// clientPubkey is the pubkey of the client that is used for the swap.
|
||||
clientPubkey *btcec.PublicKey
|
||||
|
||||
// serverPubkey is the pubkey of the server that is used for the swap.
|
||||
serverPubkey *btcec.PublicKey
|
||||
|
||||
// swapInvoice is the invoice that is used for the swap.
|
||||
swapInvoice string
|
||||
|
||||
// htlcFeeRate is the fee rate that is used for the htlc transaction.
|
||||
htlcFeeRate chainfee.SatPerKWeight
|
||||
|
||||
// sweepAddress is the address that is used to sweep the funds to.
|
||||
sweepAddress btcutil.Address
|
||||
|
||||
// finalizedHtlcTx is the finalized htlc transaction that is used in the
|
||||
// non-cooperative path for the instant out swap.
|
||||
finalizedHtlcTx *wire.MsgTx
|
||||
|
||||
// SweepTxHash is the hash of the sweep transaction.
|
||||
SweepTxHash *chainhash.Hash
|
||||
|
||||
// finalizedSweeplessSweepTx is the transaction that is used to sweep
|
||||
// the funds in the cooperative path.
|
||||
finalizedSweeplessSweepTx *wire.MsgTx
|
||||
|
||||
// sweepConfirmationHeight is the height at which the sweep
|
||||
// transaction was confirmed.
|
||||
sweepConfirmationHeight uint32
|
||||
}
|
||||
|
||||
// getHtlc returns the swap.htlc for the instant out.
|
||||
func (i *InstantOut) getHtlc(chainParams *chaincfg.Params) (*swap.Htlc, error) {
|
||||
return swap.NewHtlcV2(
|
||||
i.cltvExpiry, pubkeyTo33ByteSlice(i.serverPubkey),
|
||||
pubkeyTo33ByteSlice(i.clientPubkey), i.SwapHash, chainParams,
|
||||
)
|
||||
}
|
||||
|
||||
// createMusig2Session creates a musig2 session for the instant out.
|
||||
func (i *InstantOut) createMusig2Session(ctx context.Context,
|
||||
signer lndclient.SignerClient) ([]*input.MuSig2SessionInfo,
|
||||
[][]byte, error) {
|
||||
|
||||
// Create the htlc musig2 context.
|
||||
musig2Sessions := make([]*input.MuSig2SessionInfo, len(i.reservations))
|
||||
clientNonces := make([][]byte, len(i.reservations))
|
||||
|
||||
// Create the sessions and nonces from the reservations.
|
||||
for idx, reservation := range i.reservations {
|
||||
session, err := reservation.Musig2CreateSession(ctx, signer)
|
||||
if err != nil {
|
||||
return nil, nil, err
|
||||
}
|
||||
|
||||
musig2Sessions[idx] = session
|
||||
clientNonces[idx] = session.PublicNonce[:]
|
||||
}
|
||||
|
||||
return musig2Sessions, clientNonces, nil
|
||||
}
|
||||
|
||||
// getInputReservation returns the input reservation for the instant out.
|
||||
func (i *InstantOut) getInputReservations() (InputReservations, error) {
|
||||
if len(i.reservations) == 0 {
|
||||
return nil, errors.New("no reservations")
|
||||
}
|
||||
|
||||
inputs := make(InputReservations, len(i.reservations))
|
||||
for idx, reservation := range i.reservations {
|
||||
pkScript, err := reservation.GetPkScript()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
inputs[idx] = InputReservation{
|
||||
Outpoint: *reservation.Outpoint,
|
||||
Value: reservation.Value,
|
||||
PkScript: pkScript,
|
||||
}
|
||||
}
|
||||
|
||||
return inputs, nil
|
||||
}
|
||||
|
||||
// createHtlcTransaction creates the htlc transaction for the instant out.
|
||||
func (i *InstantOut) createHtlcTransaction(network *chaincfg.Params) (
|
||||
*wire.MsgTx, error) {
|
||||
|
||||
if network == nil {
|
||||
return nil, errors.New("no network provided")
|
||||
}
|
||||
|
||||
inputReservations, err := i.getInputReservations()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// First Create the tx.
|
||||
msgTx := wire.NewMsgTx(2)
|
||||
|
||||
// add the reservation inputs
|
||||
for _, reservation := range inputReservations {
|
||||
msgTx.AddTxIn(&wire.TxIn{
|
||||
PreviousOutPoint: reservation.Outpoint,
|
||||
})
|
||||
}
|
||||
|
||||
// Estimate the fee
|
||||
weight := htlcWeight(len(inputReservations))
|
||||
fee := i.htlcFeeRate.FeeForWeight(weight)
|
||||
if fee > i.value/5 {
|
||||
return nil, errors.New("fee is higher than 20% of " +
|
||||
"sweep value")
|
||||
}
|
||||
|
||||
htlc, err := i.getHtlc(network)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Create the sweep output
|
||||
sweepOutput := &wire.TxOut{
|
||||
Value: int64(i.value) - int64(fee),
|
||||
PkScript: htlc.PkScript,
|
||||
}
|
||||
|
||||
msgTx.AddTxOut(sweepOutput)
|
||||
|
||||
return msgTx, nil
|
||||
}
|
||||
|
||||
// createSweeplessSweepTx creates the sweepless sweep transaction for the
|
||||
// instant out.
|
||||
func (i *InstantOut) createSweeplessSweepTx(feerate chainfee.SatPerKWeight) (
|
||||
*wire.MsgTx, error) {
|
||||
|
||||
inputReservations, err := i.getInputReservations()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// First Create the tx.
|
||||
msgTx := wire.NewMsgTx(2)
|
||||
|
||||
// add the reservation inputs
|
||||
for _, reservation := range inputReservations {
|
||||
msgTx.AddTxIn(&wire.TxIn{
|
||||
PreviousOutPoint: reservation.Outpoint,
|
||||
})
|
||||
}
|
||||
|
||||
// Estimate the fee
|
||||
weight := sweeplessSweepWeight(len(inputReservations))
|
||||
fee := feerate.FeeForWeight(weight)
|
||||
if fee > i.value/5 {
|
||||
return nil, errors.New("fee is higher than 20% of " +
|
||||
"sweep value")
|
||||
}
|
||||
|
||||
pkscript, err := txscript.PayToAddrScript(i.sweepAddress)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Create the sweep output
|
||||
sweepOutput := &wire.TxOut{
|
||||
Value: int64(i.value) - int64(fee),
|
||||
PkScript: pkscript,
|
||||
}
|
||||
|
||||
msgTx.AddTxOut(sweepOutput)
|
||||
|
||||
return msgTx, nil
|
||||
}
|
||||
|
||||
// signMusig2Tx adds the server nonces to the musig2 sessions and signs the
|
||||
// transaction.
|
||||
func (i *InstantOut) signMusig2Tx(ctx context.Context,
|
||||
signer lndclient.SignerClient, tx *wire.MsgTx,
|
||||
musig2sessions []*input.MuSig2SessionInfo,
|
||||
counterPartyNonces [][66]byte) ([][]byte, error) {
|
||||
|
||||
inputs, err := i.getInputReservations()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
prevOutFetcher := inputs.GetPrevoutFetcher()
|
||||
sigHashes := txscript.NewTxSigHashes(tx, prevOutFetcher)
|
||||
sigs := make([][]byte, len(inputs))
|
||||
|
||||
for idx, reservation := range inputs {
|
||||
if !reflect.DeepEqual(tx.TxIn[idx].PreviousOutPoint,
|
||||
reservation.Outpoint) {
|
||||
|
||||
return nil, fmt.Errorf("tx input does not match " +
|
||||
"reservation")
|
||||
}
|
||||
|
||||
taprootSigHash, err := txscript.CalcTaprootSignatureHash(
|
||||
sigHashes, txscript.SigHashDefault,
|
||||
tx, idx, prevOutFetcher,
|
||||
)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var digest [32]byte
|
||||
copy(digest[:], taprootSigHash)
|
||||
|
||||
// Register the server's nonce before attempting to create our
|
||||
// partial signature.
|
||||
haveAllNonces, err := signer.MuSig2RegisterNonces(
|
||||
ctx, musig2sessions[idx].SessionID,
|
||||
[][musig2.PubNonceSize]byte{counterPartyNonces[idx]},
|
||||
)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Sanity check that we have all the nonces.
|
||||
if !haveAllNonces {
|
||||
return nil, fmt.Errorf("invalid MuSig2 session: " +
|
||||
"nonces missing")
|
||||
}
|
||||
|
||||
// Since our MuSig2 session has all nonces, we can now create
|
||||
// the local partial signature by signing the sig hash.
|
||||
sig, err := signer.MuSig2Sign(
|
||||
ctx, musig2sessions[idx].SessionID, digest, false,
|
||||
)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
sigs[idx] = sig
|
||||
}
|
||||
|
||||
return sigs, nil
|
||||
}
|
||||
|
||||
// finalizeMusig2Transaction creates the finalized transactions for either
|
||||
// the htlc or the cooperative close.
|
||||
func (i *InstantOut) finalizeMusig2Transaction(ctx context.Context,
|
||||
signer lndclient.SignerClient,
|
||||
musig2Sessions []*input.MuSig2SessionInfo,
|
||||
tx *wire.MsgTx, serverSigs [][]byte) (*wire.MsgTx, error) {
|
||||
|
||||
inputs, err := i.getInputReservations()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
for idx := range inputs {
|
||||
haveAllSigs, finalSig, err := signer.MuSig2CombineSig(
|
||||
ctx, musig2Sessions[idx].SessionID,
|
||||
[][]byte{serverSigs[idx]},
|
||||
)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if !haveAllSigs {
|
||||
return nil, fmt.Errorf("missing sigs")
|
||||
}
|
||||
|
||||
tx.TxIn[idx].Witness = wire.TxWitness{finalSig}
|
||||
}
|
||||
|
||||
return tx, nil
|
||||
}
|
||||
|
||||
// generateHtlcSweepTx creates the htlc sweep transaction for the instant out.
|
||||
func (i *InstantOut) generateHtlcSweepTx(ctx context.Context,
|
||||
signer lndclient.SignerClient, feeRate chainfee.SatPerKWeight,
|
||||
network *chaincfg.Params, blockheight uint32) (
|
||||
*wire.MsgTx, error) {
|
||||
|
||||
if network == nil {
|
||||
return nil, errors.New("no network provided")
|
||||
}
|
||||
|
||||
if i.finalizedHtlcTx == nil {
|
||||
return nil, errors.New("no finalized htlc tx")
|
||||
}
|
||||
|
||||
htlc, err := i.getHtlc(network)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Create the sweep transaction.
|
||||
sweepTx := wire.NewMsgTx(2)
|
||||
sweepTx.LockTime = blockheight
|
||||
|
||||
var weightEstimator input.TxWeightEstimator
|
||||
weightEstimator.AddP2TROutput()
|
||||
|
||||
err = htlc.AddSuccessToEstimator(&weightEstimator)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
htlcHash := i.finalizedHtlcTx.TxHash()
|
||||
|
||||
// Add the htlc input.
|
||||
sweepTx.AddTxIn(&wire.TxIn{
|
||||
PreviousOutPoint: wire.OutPoint{
|
||||
Hash: htlcHash,
|
||||
Index: 0,
|
||||
},
|
||||
SignatureScript: htlc.SigScript,
|
||||
Sequence: htlc.SuccessSequence(),
|
||||
})
|
||||
|
||||
// Add the sweep output.
|
||||
sweepPkScript, err := txscript.PayToAddrScript(i.sweepAddress)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
fee := feeRate.FeeForWeight(int64(weightEstimator.Weight()))
|
||||
|
||||
htlcOutValue := i.finalizedHtlcTx.TxOut[0].Value
|
||||
output := &wire.TxOut{
|
||||
Value: htlcOutValue - int64(fee),
|
||||
PkScript: sweepPkScript,
|
||||
}
|
||||
|
||||
sweepTx.AddTxOut(output)
|
||||
|
||||
signDesc := lndclient.SignDescriptor{
|
||||
WitnessScript: htlc.SuccessScript(),
|
||||
Output: &wire.TxOut{
|
||||
Value: htlcOutValue,
|
||||
PkScript: htlc.PkScript,
|
||||
},
|
||||
HashType: htlc.SigHash(),
|
||||
InputIndex: 0,
|
||||
KeyDesc: keychain.KeyDescriptor{
|
||||
KeyLocator: i.keyLocator,
|
||||
},
|
||||
}
|
||||
|
||||
rawSigs, err := signer.SignOutputRaw(
|
||||
ctx, sweepTx, []*lndclient.SignDescriptor{&signDesc}, nil,
|
||||
)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("sign output error: %v", err)
|
||||
}
|
||||
sig := rawSigs[0]
|
||||
|
||||
// Add witness stack to the tx input.
|
||||
sweepTx.TxIn[0].Witness, err = htlc.GenSuccessWitness(
|
||||
sig, i.swapPreimage,
|
||||
)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return sweepTx, nil
|
||||
}
|
||||
|
||||
// htlcWeight returns the weight for the htlc transaction.
|
||||
func htlcWeight(numInputs int) int64 {
|
||||
var weightEstimator input.TxWeightEstimator
|
||||
for i := 0; i < numInputs; i++ {
|
||||
weightEstimator.AddTaprootKeySpendInput(
|
||||
txscript.SigHashDefault,
|
||||
)
|
||||
}
|
||||
|
||||
weightEstimator.AddP2WSHOutput()
|
||||
|
||||
return int64(weightEstimator.Weight())
|
||||
}
|
||||
|
||||
// sweeplessSweepWeight returns the weight for the sweepless sweep transaction.
|
||||
func sweeplessSweepWeight(numInputs int) int64 {
|
||||
var weightEstimator input.TxWeightEstimator
|
||||
for i := 0; i < numInputs; i++ {
|
||||
weightEstimator.AddTaprootKeySpendInput(
|
||||
txscript.SigHashDefault,
|
||||
)
|
||||
}
|
||||
|
||||
weightEstimator.AddP2TROutput()
|
||||
|
||||
return int64(weightEstimator.Weight())
|
||||
}
|
||||
|
||||
// pubkeyTo33ByteSlice converts a pubkey to a 33 byte slice.
|
||||
func pubkeyTo33ByteSlice(pubkey *btcec.PublicKey) [33]byte {
|
||||
var pubkeyBytes [33]byte
|
||||
copy(pubkeyBytes[:], pubkey.SerializeCompressed())
|
||||
|
||||
return pubkeyBytes
|
||||
}
|
||||
|
||||
// toNonces converts a byte slice to a 66 byte slice.
|
||||
func toNonces(nonces [][]byte) ([][66]byte, error) {
|
||||
res := make([][66]byte, 0, len(nonces))
|
||||
for _, n := range nonces {
|
||||
n := n
|
||||
nonce, err := byteSliceTo66ByteSlice(n)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
res = append(res, nonce)
|
||||
}
|
||||
|
||||
return res, nil
|
||||
}
|
||||
|
||||
// byteSliceTo66ByteSlice converts a byte slice to a 66 byte slice.
|
||||
func byteSliceTo66ByteSlice(b []byte) ([66]byte, error) {
|
||||
if len(b) != 66 {
|
||||
return [66]byte{}, fmt.Errorf("invalid byte slice length")
|
||||
}
|
||||
|
||||
var res [66]byte
|
||||
copy(res[:], b)
|
||||
|
||||
return res, nil
|
||||
}
|
||||
@ -0,0 +1,73 @@
|
||||
package instantout
|
||||
|
||||
import (
|
||||
"context"
|
||||
|
||||
"github.com/btcsuite/btcd/btcutil"
|
||||
"github.com/btcsuite/btcd/txscript"
|
||||
"github.com/btcsuite/btcd/wire"
|
||||
"github.com/lightninglabs/loop/instantout/reservation"
|
||||
)
|
||||
|
||||
const (
|
||||
KeyFamily = int32(42069)
|
||||
)
|
||||
|
||||
// InstantLoopOutStore is the interface that needs to be implemented by a
|
||||
// store that wants to be used by the instant loop out manager.
|
||||
type InstantLoopOutStore interface {
|
||||
// CreateInstantLoopOut adds a new instant loop out to the store.
|
||||
CreateInstantLoopOut(ctx context.Context, instantOut *InstantOut) error
|
||||
|
||||
// UpdateInstantLoopOut updates an existing instant loop out in the
|
||||
// store.
|
||||
UpdateInstantLoopOut(ctx context.Context, instantOut *InstantOut) error
|
||||
|
||||
// GetInstantLoopOut returns the instant loop out for the given swap
|
||||
// hash.
|
||||
GetInstantLoopOut(ctx context.Context, swapHash []byte) (*InstantOut, error)
|
||||
|
||||
// ListInstantLoopOuts returns all instant loop outs that are in the
|
||||
// store.
|
||||
ListInstantLoopOuts(ctx context.Context) ([]*InstantOut, error)
|
||||
}
|
||||
|
||||
// ReservationManager handles fetching and locking of reservations.
|
||||
type ReservationManager interface {
|
||||
// GetReservation returns the reservation for the given id.
|
||||
GetReservation(ctx context.Context, id reservation.ID) (
|
||||
*reservation.Reservation, error)
|
||||
|
||||
// LockReservation locks the reservation for the given id.
|
||||
LockReservation(ctx context.Context, id reservation.ID) error
|
||||
|
||||
// UnlockReservation unlocks the reservation for the given id.
|
||||
UnlockReservation(ctx context.Context, id reservation.ID) error
|
||||
}
|
||||
|
||||
// InputReservations is a helper struct for the input reservations.
|
||||
type InputReservations []InputReservation
|
||||
|
||||
// InputReservation is a helper struct for the input reservation.
|
||||
type InputReservation struct {
|
||||
Outpoint wire.OutPoint
|
||||
Value btcutil.Amount
|
||||
PkScript []byte
|
||||
}
|
||||
|
||||
// Output returns the output for the input reservation.
|
||||
func (r InputReservation) Output() *wire.TxOut {
|
||||
return wire.NewTxOut(int64(r.Value), r.PkScript)
|
||||
}
|
||||
|
||||
// GetPrevoutFetcher returns a prevout fetcher for the input reservations.
|
||||
func (i InputReservations) GetPrevoutFetcher() txscript.PrevOutputFetcher {
|
||||
prevOuts := make(map[wire.OutPoint]*wire.TxOut)
|
||||
|
||||
// add the reservation inputs
|
||||
for _, reservation := range i {
|
||||
prevOuts[reservation.Outpoint] = reservation.Output()
|
||||
}
|
||||
|
||||
return txscript.NewMultiPrevOutFetcher(prevOuts)
|
||||
}
|
||||
@ -0,0 +1,26 @@
|
||||
package instantout
|
||||
|
||||
import (
|
||||
"github.com/btcsuite/btclog"
|
||||
"github.com/lightningnetwork/lnd/build"
|
||||
)
|
||||
|
||||
// Subsystem defines the sub system name of this package.
|
||||
const Subsystem = "INST"
|
||||
|
||||
// log is a logger that is initialized with no output filters. This
|
||||
// means the package will not perform any logging by default until the caller
|
||||
// requests it.
|
||||
var log btclog.Logger
|
||||
|
||||
// The default amount of logging is none.
|
||||
func init() {
|
||||
UseLogger(build.NewSubLogger(Subsystem, nil))
|
||||
}
|
||||
|
||||
// UseLogger uses a specified Logger to output package logging info.
|
||||
// This should be used in preference to SetLogWriter if the caller is also
|
||||
// using btclog.
|
||||
func UseLogger(logger btclog.Logger) {
|
||||
log = logger
|
||||
}
|
||||
Loading…
Reference in New Issue