mirror of
https://github.com/aljazceru/lspd.git
synced 2025-12-18 14:24:21 +01:00
398 lines
14 KiB
Go
398 lines
14 KiB
Go
package interceptor
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"encoding/hex"
|
|
"log"
|
|
"math/big"
|
|
"time"
|
|
|
|
"github.com/breez/lspd/chain"
|
|
"github.com/breez/lspd/common"
|
|
"github.com/breez/lspd/config"
|
|
"github.com/breez/lspd/lightning"
|
|
"github.com/breez/lspd/lsps0"
|
|
"github.com/breez/lspd/notifications"
|
|
"github.com/btcsuite/btcd/wire"
|
|
"golang.org/x/exp/slices"
|
|
"golang.org/x/sync/singleflight"
|
|
)
|
|
|
|
type Interceptor struct {
|
|
client lightning.Client
|
|
config *config.NodeConfig
|
|
store InterceptStore
|
|
openingService common.OpeningService
|
|
feeEstimator chain.FeeEstimator
|
|
feeStrategy chain.FeeStrategy
|
|
payHashGroup singleflight.Group
|
|
notificationService *notifications.NotificationService
|
|
}
|
|
|
|
func NewInterceptHandler(
|
|
client lightning.Client,
|
|
config *config.NodeConfig,
|
|
store InterceptStore,
|
|
openingService common.OpeningService,
|
|
feeEstimator chain.FeeEstimator,
|
|
feeStrategy chain.FeeStrategy,
|
|
notificationService *notifications.NotificationService,
|
|
) *Interceptor {
|
|
return &Interceptor{
|
|
client: client,
|
|
config: config,
|
|
store: store,
|
|
openingService: openingService,
|
|
feeEstimator: feeEstimator,
|
|
feeStrategy: feeStrategy,
|
|
notificationService: notificationService,
|
|
}
|
|
}
|
|
|
|
func (i *Interceptor) Intercept(req common.InterceptRequest) common.InterceptResult {
|
|
reqPaymentHashStr := hex.EncodeToString(req.PaymentHash)
|
|
log.Printf("Intercept: scid: %s, paymentHash: %s, outgoingAmount: %v, outgoingExpiry: %v, incomingExpiry: %v", req.Scid.ToString(), reqPaymentHashStr, req.OutgoingAmountMsat, req.OutgoingExpiry, req.IncomingExpiry)
|
|
resp, _, _ := i.payHashGroup.Do(reqPaymentHashStr, func() (interface{}, error) {
|
|
token, params, paymentHash, paymentSecret, destination, incomingAmountMsat, outgoingAmountMsat, channelPoint, tag, err := i.store.PaymentInfo(req.PaymentHash)
|
|
if err != nil {
|
|
log.Printf("paymentInfo(%x) error: %v", req.PaymentHash, err)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_NODE_FAILURE,
|
|
}, nil
|
|
}
|
|
|
|
isRegistered := paymentSecret != nil
|
|
// Sanity check. If the payment is registered, the destination is always set.
|
|
if isRegistered && (destination == nil || len(destination) != 33) {
|
|
log.Printf("ERROR: Payment was registered without destination. paymentHash: %s", reqPaymentHashStr)
|
|
}
|
|
|
|
isProbe := isRegistered && !bytes.Equal(paymentHash, req.PaymentHash)
|
|
nextHop, _ := i.client.GetPeerId(&req.Scid)
|
|
if err != nil {
|
|
log.Printf("GetPeerId(%s) error: %v", req.Scid.ToString(), err)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}, nil
|
|
}
|
|
|
|
// If the payment was registered, but the next hop is not the destination
|
|
// that means we are not the last hop of the payment, so we'll just forward.
|
|
if isRegistered && nextHop != nil && !bytes.Equal(nextHop, destination) {
|
|
log.Printf("paymentHash: %s, nextHop (%s) != destination (%s)", reqPaymentHashStr, hex.EncodeToString(nextHop), hex.EncodeToString(destination))
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}, nil
|
|
}
|
|
|
|
// nextHop is set if the sender's scid corresponds to a known channel.
|
|
// destination is set if the payment was registered for a channel open.
|
|
// The 'actual' next hop will be either of those.
|
|
if nextHop == nil {
|
|
|
|
// If the next hop cannot be deduced from the scid, and the payment
|
|
// is not registered, there's nothing left to be done. Just continue.
|
|
if !isRegistered {
|
|
log.Printf("paymentHash: %s, nextHop == nil and not registered", reqPaymentHashStr)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}, nil
|
|
}
|
|
|
|
// The payment was registered, so the next hop is the registered
|
|
// destination
|
|
nextHop = destination
|
|
}
|
|
|
|
isConnected, err := i.client.IsConnected(nextHop)
|
|
if err != nil {
|
|
log.Printf("IsConnected(%x) error: %v", nextHop, err)
|
|
return &common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_CHANNEL_FAILURE,
|
|
}, nil
|
|
}
|
|
|
|
if isProbe {
|
|
// If this is a known probe, we'll quit early for non-connected clients.
|
|
if !isConnected {
|
|
log.Printf("paymentHash: %s, probe and not connected", reqPaymentHashStr)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}, nil
|
|
}
|
|
|
|
// If it's a probe, they are connected, but need a channel, we'll return
|
|
// INCORRECT_OR_UNKNOWN_PAYMENT_DETAILS. This is an out-of-spec
|
|
// error code, because it shouldn't be returned by an intermediate
|
|
// node. But senders implementnig the probing-01: prefix should
|
|
// know that the actual payment would probably succeed.
|
|
if channelPoint == nil {
|
|
log.Printf("paymentHash: %s, probe and channelPoint == nil", reqPaymentHashStr)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_INCORRECT_OR_UNKNOWN_PAYMENT_DETAILS,
|
|
}, nil
|
|
}
|
|
}
|
|
|
|
if isConnected {
|
|
// If the peer is connected, notify anyway, but don't wait for the result.
|
|
go i.notificationService.Notify(
|
|
hex.EncodeToString(nextHop),
|
|
reqPaymentHashStr,
|
|
)
|
|
} else {
|
|
// Make sure the client is connected by potentially notifying them to come online.
|
|
notifyResult := i.notifyAndWait(reqPaymentHashStr, nextHop, isRegistered)
|
|
if notifyResult != nil {
|
|
log.Printf("paymentHash: %s, !isConnected and notifyResult != nil", reqPaymentHashStr)
|
|
// return *notifyResult, nil
|
|
}
|
|
}
|
|
|
|
// The peer is online, we can resume the htlc if it's not a channel open.
|
|
if !isRegistered {
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}, nil
|
|
}
|
|
|
|
// The first htlc of a MPP will open the channel.
|
|
if channelPoint == nil {
|
|
// TODO: When opening_fee_params is enforced, turn this check in a temporary channel failure.
|
|
if params == nil {
|
|
log.Printf("DEPRECATED: Intercepted htlc with deprecated fee mechanism. Using default fees. payment hash: %s", reqPaymentHashStr)
|
|
params = &common.OpeningFeeParams{
|
|
MinFeeMsat: uint64(i.config.ChannelMinimumFeeMsat),
|
|
Proportional: uint32(i.config.ChannelFeePermyriad * 100),
|
|
ValidUntil: time.Now().UTC().Add(time.Duration(time.Hour * 24)).Format(lsps0.TIME_FORMAT),
|
|
MinLifetime: uint32(i.config.MaxInactiveDuration / 600),
|
|
MaxClientToSelfDelay: uint32(10000),
|
|
}
|
|
}
|
|
|
|
// Make sure the cltv delta is enough.
|
|
if int64(req.IncomingExpiry)-int64(req.OutgoingExpiry) < int64(i.config.TimeLockDelta) {
|
|
log.Printf("paymentHash: %s, outgoingExpiry: %v, incomingExpiry: %v, i.config.TimeLockDelta: %v", reqPaymentHashStr, req.OutgoingExpiry, req.IncomingExpiry, i.config.TimeLockDelta)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_CHANNEL_FAILURE,
|
|
}, nil
|
|
}
|
|
|
|
validUntil, err := time.Parse(lsps0.TIME_FORMAT, params.ValidUntil)
|
|
if err != nil {
|
|
log.Printf("paymentHash: %s, time.Parse(%s, %s) failed. Failing channel open: %v", reqPaymentHashStr, lsps0.TIME_FORMAT, params.ValidUntil, err)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_CHANNEL_FAILURE,
|
|
}, nil
|
|
}
|
|
|
|
// Make sure the opening_fee_params are not expired.
|
|
// If they are expired, but the current chain fee is fine, open channel anyway.
|
|
if time.Now().UTC().After(validUntil) {
|
|
if !i.openingService.IsCurrentChainFeeCheaper(token, params) {
|
|
log.Printf("Intercepted expired payment registration. Failing payment. payment hash: %s, valid until: %s", reqPaymentHashStr, params.ValidUntil)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_CHANNEL_FAILURE,
|
|
}, nil
|
|
}
|
|
|
|
log.Printf("Intercepted expired payment registration. Opening channel anyway, because it's cheaper at the current rate. paymenthash: %s, params: %+v", reqPaymentHashStr, params)
|
|
}
|
|
|
|
channelPoint, err = i.openChannel(req.PaymentHash, destination, incomingAmountMsat, tag)
|
|
if err != nil {
|
|
log.Printf("paymentHash: %s, openChannel(%x, %v) err: %v", reqPaymentHashStr, destination, incomingAmountMsat, err)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_CHANNEL_FAILURE,
|
|
}, nil
|
|
}
|
|
}
|
|
|
|
var bigProd, bigAmt big.Int
|
|
amt := (bigAmt.Div(bigProd.Mul(big.NewInt(outgoingAmountMsat), big.NewInt(int64(req.OutgoingAmountMsat))), big.NewInt(incomingAmountMsat))).Int64()
|
|
|
|
deadline := time.Now().Add(60 * time.Second)
|
|
|
|
for {
|
|
chanResult, _ := i.client.GetChannel(destination, *channelPoint)
|
|
if chanResult != nil {
|
|
log.Printf("paymentHash: %s, channel opened successfully alias: %v, confirmed: %v", reqPaymentHashStr, chanResult.InitialChannelID.ToString(), chanResult.ConfirmedChannelID.ToString())
|
|
|
|
err := i.store.InsertChannel(
|
|
uint64(chanResult.InitialChannelID),
|
|
uint64(chanResult.ConfirmedChannelID),
|
|
channelPoint.String(),
|
|
destination,
|
|
time.Now(),
|
|
)
|
|
|
|
if err != nil {
|
|
log.Printf("paymentHash: %s, insertChannel error: %v", reqPaymentHashStr, err)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_CHANNEL_FAILURE,
|
|
}, nil
|
|
}
|
|
|
|
channelID := chanResult.ConfirmedChannelID
|
|
if uint64(channelID) == 0 {
|
|
channelID = chanResult.InitialChannelID
|
|
}
|
|
|
|
useLegacyOnionBlob := slices.Contains(i.config.LegacyOnionTokens, token)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME_WITH_ONION,
|
|
Destination: destination,
|
|
ChannelPoint: channelPoint,
|
|
Scid: channelID,
|
|
PaymentSecret: paymentSecret,
|
|
AmountMsat: uint64(amt),
|
|
TotalAmountMsat: uint64(outgoingAmountMsat),
|
|
UseLegacyOnionBlob: useLegacyOnionBlob,
|
|
}, nil
|
|
}
|
|
|
|
log.Printf("paymentHash: %s, waiting for channel to get opened.... %v", reqPaymentHashStr, destination)
|
|
if time.Now().After(deadline) {
|
|
log.Printf("paymentHash: %s, Stop retrying getChannel(%v, %v)", reqPaymentHashStr, destination, channelPoint.String())
|
|
break
|
|
}
|
|
<-time.After(1 * time.Second)
|
|
}
|
|
|
|
log.Printf("paymentHash: %s, Error: Channel failed to open... timed out. ", reqPaymentHashStr)
|
|
return common.InterceptResult{
|
|
Action: common.INTERCEPT_FAIL_HTLC_WITH_CODE,
|
|
FailureCode: common.FAILURE_TEMPORARY_CHANNEL_FAILURE,
|
|
}, nil
|
|
})
|
|
|
|
return resp.(common.InterceptResult)
|
|
}
|
|
|
|
func (i *Interceptor) notifyAndWait(reqPaymentHashStr string, nextHop []byte, isRegistered bool) *common.InterceptResult {
|
|
// If not connected, send a notification to the registered
|
|
// notification service for this client if available.
|
|
notified, err := i.notificationService.Notify(
|
|
hex.EncodeToString(nextHop),
|
|
reqPaymentHashStr,
|
|
)
|
|
|
|
// If this errors or the client is not notified, the client
|
|
// is offline or unknown. We'll resume the HTLC (which will
|
|
// result in UNKOWN_NEXT_PEER)
|
|
if err != nil || !notified {
|
|
return &common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}
|
|
}
|
|
|
|
log.Printf("paymentHash %s, Notified %x of pending htlc", reqPaymentHashStr, nextHop)
|
|
d, err := time.ParseDuration(i.config.NotificationTimeout)
|
|
if err != nil {
|
|
log.Printf("WARN: No NotificationTimeout set. Using default 1m")
|
|
d = time.Minute
|
|
}
|
|
timeout := time.Now().Add(d)
|
|
|
|
// Wait for a while to allow the client to come online.
|
|
err = i.client.WaitOnline(nextHop, timeout)
|
|
|
|
// If there's an error waiting, resume the htlc. It will
|
|
// probably fail with UNKNOWN_NEXT_PEER.
|
|
if err != nil {
|
|
log.Printf(
|
|
"paymentHash %s, waiting for peer %x to come online failed with %v",
|
|
reqPaymentHashStr,
|
|
nextHop,
|
|
err,
|
|
)
|
|
return &common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}
|
|
}
|
|
|
|
log.Printf("paymentHash %s, Peer %x is back online. Continue htlc.", reqPaymentHashStr, nextHop)
|
|
// At this point we know a few things.
|
|
// - This is either a channel partner or a registered payment
|
|
// - they were offline
|
|
// - They got notified about the htlc
|
|
// - They came back online
|
|
// So if this payment was not registered, this is a channel
|
|
// partner and we have to wait for the channel to become active
|
|
// before we can forward.
|
|
if !isRegistered {
|
|
err = i.client.WaitChannelActive(nextHop, timeout)
|
|
if err != nil {
|
|
log.Printf(
|
|
"paymentHash %s, waiting for channel with %x to become active failed with %v",
|
|
reqPaymentHashStr,
|
|
nextHop,
|
|
err,
|
|
)
|
|
return &common.InterceptResult{
|
|
Action: common.INTERCEPT_RESUME,
|
|
}
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (i *Interceptor) openChannel(paymentHash, destination []byte, incomingAmountMsat int64, tag *string) (*wire.OutPoint, error) {
|
|
capacity := incomingAmountMsat/1000 + i.config.AdditionalChannelCapacity
|
|
if capacity == i.config.PublicChannelAmount {
|
|
capacity++
|
|
}
|
|
|
|
fee, err := i.feeEstimator.EstimateFeeRate(
|
|
context.Background(),
|
|
i.feeStrategy,
|
|
)
|
|
if err != nil || fee == nil {
|
|
log.Printf("Error estimating chain fee, fallback to target conf: %v", err)
|
|
fee = &chain.FeeEstimation{
|
|
TargetConf: &i.config.TargetConf,
|
|
}
|
|
}
|
|
|
|
log.Printf(
|
|
"Opening zero conf channel. Paymenthash: %x, Destination: %x, capacity: %v, fee: %s",
|
|
paymentHash,
|
|
destination,
|
|
capacity,
|
|
fee.String(),
|
|
)
|
|
channelPoint, err := i.client.OpenChannel(&lightning.OpenChannelRequest{
|
|
Destination: destination,
|
|
CapacitySat: uint64(capacity),
|
|
MinConfs: i.config.MinConfs,
|
|
IsPrivate: true,
|
|
IsZeroConf: true,
|
|
FeeSatPerVByte: fee.SatPerVByte,
|
|
TargetConf: fee.TargetConf,
|
|
})
|
|
if err != nil {
|
|
log.Printf("paymenthash %x, client.OpenChannelSync(%x, %v) error: %v", paymentHash, destination, capacity, err)
|
|
return nil, err
|
|
}
|
|
sendOpenChannelEmailNotification(
|
|
paymentHash,
|
|
incomingAmountMsat,
|
|
destination,
|
|
capacity,
|
|
channelPoint.String(),
|
|
tag,
|
|
)
|
|
err = i.store.SetFundingTx(paymentHash, channelPoint)
|
|
return channelPoint, err
|
|
}
|