lnd/itest/lnd_route_blinding_test.go

791 lines
24 KiB
Go

package itest
import (
"bytes"
"context"
"crypto/sha256"
"encoding/hex"
"time"
"github.com/btcsuite/btcd/btcec/v2"
"github.com/btcsuite/btcd/btcutil"
sphinx "github.com/lightningnetwork/lightning-onion"
"github.com/lightningnetwork/lnd/chainreg"
"github.com/lightningnetwork/lnd/lnrpc"
"github.com/lightningnetwork/lnd/lnrpc/routerrpc"
"github.com/lightningnetwork/lnd/lntest"
"github.com/lightningnetwork/lnd/lntest/node"
"github.com/lightningnetwork/lnd/lntypes"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/record"
"github.com/lightningnetwork/lnd/routing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// testQueryBlindedRoutes tests querying routes to blinded routes. To do this,
// it sets up a nework of Alice - Bob - Carol and creates a mock blinded route
// that uses Carol as the introduction node (plus dummy hops to cover multiple
// hops). The test simply asserts that the structure of the route is as
// expected. It also includes the edge case of a single-hop blinded route,
// which indicates that the introduction node is the recipient.
func testQueryBlindedRoutes(ht *lntest.HarnessTest) {
var (
// Convenience aliases.
alice = ht.Alice
bob = ht.Bob
)
// Setup a two hop channel network: Alice -- Bob -- Carol.
// We set our proportional fee for these channels to zero, so that
// our calculations are easier. This is okay, because we're not testing
// the basic mechanics of pathfinding in this test.
chanAmt := btcutil.Amount(100000)
chanPointAliceBob := ht.OpenChannel(
alice, bob, lntest.OpenChannelParams{
Amt: chanAmt,
BaseFee: 10000,
FeeRate: 0,
UseBaseFee: true,
UseFeeRate: true,
},
)
carol := ht.NewNode("Carol", nil)
ht.EnsureConnected(bob, carol)
var bobCarolBase uint64 = 2000
chanPointBobCarol := ht.OpenChannel(
bob, carol, lntest.OpenChannelParams{
Amt: chanAmt,
BaseFee: bobCarolBase,
FeeRate: 0,
UseBaseFee: true,
UseFeeRate: true,
},
)
// Wait for Alice to see Bob/Carol's channel because she'll need it for
// pathfinding.
ht.AssertTopologyChannelOpen(alice, chanPointBobCarol)
// Lookup full channel info so that we have channel ids for our route.
aliceBobChan := ht.GetChannelByChanPoint(alice, chanPointAliceBob)
bobCarolChan := ht.GetChannelByChanPoint(bob, chanPointBobCarol)
// Sanity check that bob's fee is as expected.
chanInfoReq := &lnrpc.ChanInfoRequest{
ChanId: bobCarolChan.ChanId,
}
bobCarolInfo := bob.RPC.GetChanInfo(chanInfoReq)
// Our test relies on knowing the fee rate for bob - carol to set the
// fees we expect for our route. Perform a quick sanity check that our
// policy is as expected.
var policy *lnrpc.RoutingPolicy
if bobCarolInfo.Node1Pub == bob.PubKeyStr {
policy = bobCarolInfo.Node1Policy
} else {
policy = bobCarolInfo.Node2Policy
}
require.Equal(ht, bobCarolBase, uint64(policy.FeeBaseMsat), "base fee")
require.EqualValues(ht, 0, policy.FeeRateMilliMsat, "fee rate")
// We'll also need the current block height to calculate our locktimes.
info := alice.RPC.GetInfo()
// Since we created channels with default parameters, we can assume
// that all of our channels have the default cltv delta.
bobCarolDelta := uint32(chainreg.DefaultBitcoinTimeLockDelta)
// Create arbitrary pubkeys for use in our blinded route. They're not
// actually used functionally in this test, so we can just make them up.
var (
_, blindingPoint = btcec.PrivKeyFromBytes([]byte{1})
_, carolBlinded = btcec.PrivKeyFromBytes([]byte{2})
_, blindedHop1 = btcec.PrivKeyFromBytes([]byte{3})
_, blindedHop2 = btcec.PrivKeyFromBytes([]byte{4})
encryptedDataCarol = []byte{1, 2, 3}
encryptedData1 = []byte{4, 5, 6}
encryptedData2 = []byte{7, 8, 9}
blindingBytes = blindingPoint.SerializeCompressed()
carolBlindedBytes = carolBlinded.SerializeCompressed()
blinded1Bytes = blindedHop1.SerializeCompressed()
blinded2Bytes = blindedHop2.SerializeCompressed()
)
// Now we create a blinded route which uses carol as an introduction
// node followed by two dummy hops (the arbitrary pubkeys in our
// blinded route above:
// Carol --- B1 --- B2
route := &lnrpc.BlindedPath{
IntroductionNode: carol.PubKey[:],
BlindingPoint: blindingBytes,
BlindedHops: []*lnrpc.BlindedHop{
{
// The first hop in the blinded route is
// expected to be the introduction node.
BlindedNode: carolBlindedBytes,
EncryptedData: encryptedDataCarol,
},
{
BlindedNode: blinded1Bytes,
EncryptedData: encryptedData1,
},
{
BlindedNode: blinded2Bytes,
EncryptedData: encryptedData2,
},
},
}
// Create a blinded payment that has aggregate cltv and fee params
// for our route.
var (
blindedBaseFee uint64 = 1500
blindedCltvDelta uint32 = 125
)
blindedPayment := &lnrpc.BlindedPaymentPath{
BlindedPath: route,
BaseFeeMsat: blindedBaseFee,
TotalCltvDelta: blindedCltvDelta,
}
// Query for a route to the blinded path constructed above.
var paymentAmt int64 = 100_000
req := &lnrpc.QueryRoutesRequest{
AmtMsat: paymentAmt,
BlindedPaymentPaths: []*lnrpc.BlindedPaymentPath{
blindedPayment,
},
}
resp := alice.RPC.QueryRoutes(req)
require.Len(ht, resp.Routes, 1)
// Payment amount and cltv will be included for the bob/carol edge
// (because we apply on the outgoing hop), and the blinded portion of
// the route.
totalFee := bobCarolBase + blindedBaseFee
totalAmt := uint64(paymentAmt) + totalFee
totalCltv := info.BlockHeight + bobCarolDelta + blindedCltvDelta
// Alice -> Bob
// Forward: total - bob carol fees
// Expiry: total - bob carol delta
//
// Bob -> Carol
// Forward: 101500 (total + blinded fees)
// Expiry: Height + blinded cltv delta
// Encrypted Data: enc_carol
//
// Carol -> Blinded 1
// Forward/ Expiry: 0
// Encrypted Data: enc_1
//
// Blinded 1 -> Blinded 2
// Forward/ Expiry: Height
// Encrypted Data: enc_2
hop0Amount := int64(totalAmt - bobCarolBase)
hop0Expiry := totalCltv - bobCarolDelta
finalHopExpiry := totalCltv - bobCarolDelta - blindedCltvDelta
expectedRoute := &lnrpc.Route{
TotalTimeLock: totalCltv,
TotalAmtMsat: int64(totalAmt),
TotalFeesMsat: int64(totalFee),
Hops: []*lnrpc.Hop{
{
ChanId: aliceBobChan.ChanId,
Expiry: hop0Expiry,
AmtToForwardMsat: hop0Amount,
FeeMsat: int64(bobCarolBase),
PubKey: bob.PubKeyStr,
},
{
ChanId: bobCarolChan.ChanId,
PubKey: carol.PubKeyStr,
BlindingPoint: blindingBytes,
FeeMsat: int64(blindedBaseFee),
EncryptedData: encryptedDataCarol,
},
{
PubKey: hex.EncodeToString(
blinded1Bytes,
),
EncryptedData: encryptedData1,
},
{
PubKey: hex.EncodeToString(
blinded2Bytes,
),
AmtToForwardMsat: paymentAmt,
Expiry: finalHopExpiry,
EncryptedData: encryptedData2,
TotalAmtMsat: uint64(paymentAmt),
},
},
}
r := resp.Routes[0]
assert.Equal(ht, expectedRoute.TotalTimeLock, r.TotalTimeLock)
assert.Equal(ht, expectedRoute.TotalAmtMsat, r.TotalAmtMsat)
assert.Equal(ht, expectedRoute.TotalFeesMsat, r.TotalFeesMsat)
assert.Equal(ht, len(expectedRoute.Hops), len(r.Hops))
for i, hop := range expectedRoute.Hops {
assert.Equal(ht, hop.PubKey, r.Hops[i].PubKey,
"hop: %v pubkey", i)
assert.Equal(ht, hop.ChanId, r.Hops[i].ChanId,
"hop: %v chan id", i)
assert.Equal(ht, hop.Expiry, r.Hops[i].Expiry,
"hop: %v expiry", i)
assert.Equal(ht, hop.AmtToForwardMsat,
r.Hops[i].AmtToForwardMsat, "hop: %v forward", i)
assert.Equal(ht, hop.FeeMsat, r.Hops[i].FeeMsat,
"hop: %v fee", i)
assert.Equal(ht, hop.BlindingPoint, r.Hops[i].BlindingPoint,
"hop: %v blinding point", i)
assert.Equal(ht, hop.EncryptedData, r.Hops[i].EncryptedData,
"hop: %v encrypted data", i)
}
// Dispatch a payment to our blinded route.
preimage := [33]byte{1, 2, 3}
hash := sha256.Sum256(preimage[:])
sendReq := &routerrpc.SendToRouteRequest{
PaymentHash: hash[:],
Route: r,
}
htlcAttempt := alice.RPC.SendToRouteV2(sendReq)
// Since Carol doesn't understand blinded routes, we expect her to fail
// the payment because the onion payload is invalid (missing amount to
// forward).
require.NotNil(ht, htlcAttempt.Failure)
require.Equal(ht, uint32(2), htlcAttempt.Failure.FailureSourceIndex)
// Next, we test an edge case where just an introduction node is
// included as a "single hop blinded route".
sendToIntroCLTVFinal := uint32(15)
sendToIntroTimelock := info.BlockHeight + bobCarolDelta +
sendToIntroCLTVFinal
introNodeBlinded := &lnrpc.BlindedPaymentPath{
BlindedPath: &lnrpc.BlindedPath{
IntroductionNode: carol.PubKey[:],
BlindingPoint: blindingBytes,
BlindedHops: []*lnrpc.BlindedHop{
{
// The first hop in the blinded route is
// expected to be the introduction node.
BlindedNode: carolBlindedBytes,
EncryptedData: encryptedDataCarol,
},
},
},
// Fees should be zero for a single hop blinded path, and the
// total cltv expiry is just expected to cover the final cltv
// delta of the receiving node (ie, the introduction node).
BaseFeeMsat: 0,
TotalCltvDelta: sendToIntroCLTVFinal,
}
req = &lnrpc.QueryRoutesRequest{
AmtMsat: paymentAmt,
BlindedPaymentPaths: []*lnrpc.BlindedPaymentPath{
introNodeBlinded,
},
}
// Assert that we have one route, and two hops: Alice/Bob and Bob/Carol.
resp = alice.RPC.QueryRoutes(req)
require.Len(ht, resp.Routes, 1)
require.Len(ht, resp.Routes[0].Hops, 2)
require.Equal(ht, resp.Routes[0].TotalTimeLock, sendToIntroTimelock)
ht.CloseChannel(alice, chanPointAliceBob)
ht.CloseChannel(bob, chanPointBobCarol)
}
type blindedForwardTest struct {
ht *lntest.HarnessTest
carol *node.HarnessNode
dave *node.HarnessNode
channels []*lnrpc.ChannelPoint
carolInterceptor routerrpc.Router_HtlcInterceptorClient
preimage [32]byte
// cancel will cancel the test's top level context.
cancel func()
}
func newBlindedForwardTest(ht *lntest.HarnessTest) (context.Context,
*blindedForwardTest) {
ctx, cancel := context.WithCancel(context.Background())
return ctx, &blindedForwardTest{
ht: ht,
cancel: cancel,
preimage: [32]byte{1, 2, 3},
}
}
// setup spins up additional nodes needed for our test and creates a four hop
// network for testing blinded forwarding and returns a blinded route from
// Bob -> Carol -> Dave, with Bob acting as the introduction point and an
// interceptor on Carol's node to manage HTLCs (as Dave does not yet support
// receiving).
func (b *blindedForwardTest) setup(
ctx context.Context) *routing.BlindedPayment {
b.carol = b.ht.NewNode("Carol", []string{
"requireinterceptor",
})
var err error
b.carolInterceptor, err = b.carol.RPC.Router.HtlcInterceptor(ctx)
require.NoError(b.ht, err, "interceptor")
b.dave = b.ht.NewNode("Dave", nil)
b.channels = setupFourHopNetwork(b.ht, b.carol, b.dave)
// Create a blinded route to Dave via Bob --- Carol --- Dave:
bobChan := b.ht.GetChannelByChanPoint(b.ht.Bob, b.channels[1])
carolChan := b.ht.GetChannelByChanPoint(b.carol, b.channels[2])
edges := []*forwardingEdge{
getForwardingEdge(b.ht, b.ht.Bob, bobChan.ChanId),
getForwardingEdge(b.ht, b.carol, carolChan.ChanId),
}
davePk, err := btcec.ParsePubKey(b.dave.PubKey[:])
require.NoError(b.ht, err, "dave pubkey")
return b.createBlindedRoute(edges, davePk, 50)
}
// cleanup tears down all channels created by the test and cancels the top
// level context used in the test.
func (b *blindedForwardTest) cleanup() {
b.ht.CloseChannel(b.ht.Alice, b.channels[0])
b.ht.CloseChannel(b.ht.Bob, b.channels[1])
b.ht.CloseChannel(b.carol, b.channels[2])
b.cancel()
}
// createRouteToBlinded queries for a route from alice to the blinded path
// provided.
//
//nolint:gomnd
func (b *blindedForwardTest) createRouteToBlinded(paymentAmt int64,
route *routing.BlindedPayment) *lnrpc.Route {
intro := route.BlindedPath.IntroductionPoint.SerializeCompressed()
blinding := route.BlindedPath.BlindingPoint.SerializeCompressed()
blindedRoute := &lnrpc.BlindedPath{
IntroductionNode: intro,
BlindingPoint: blinding,
BlindedHops: make(
[]*lnrpc.BlindedHop,
len(route.BlindedPath.BlindedHops),
),
}
for i, hop := range route.BlindedPath.BlindedHops {
blindedRoute.BlindedHops[i] = &lnrpc.BlindedHop{
BlindedNode: hop.BlindedNodePub.SerializeCompressed(),
EncryptedData: hop.CipherText,
}
}
blindedPath := &lnrpc.BlindedPaymentPath{
BlindedPath: blindedRoute,
BaseFeeMsat: uint64(
route.BaseFee,
),
ProportionalFeeRate: route.ProportionalFeeRate,
TotalCltvDelta: uint32(
route.CltvExpiryDelta,
),
}
req := &lnrpc.QueryRoutesRequest{
AmtMsat: paymentAmt,
// Our fee limit doesn't really matter, we just want to
// be able to make the payment.
FeeLimit: &lnrpc.FeeLimit{
Limit: &lnrpc.FeeLimit_Percent{
Percent: 50,
},
},
BlindedPaymentPaths: []*lnrpc.BlindedPaymentPath{
blindedPath,
},
}
resp := b.ht.Alice.RPC.QueryRoutes(req)
require.Greater(b.ht, len(resp.Routes), 0, "no routes")
require.Len(b.ht, resp.Routes[0].Hops, 3, "unexpected route length")
return resp.Routes[0]
}
// sendBlindedPayment dispatches a payment to the route provided.
func (b *blindedForwardTest) sendBlindedPayment(ctx context.Context,
route *lnrpc.Route) {
hash := sha256.Sum256(b.preimage[:])
sendReq := &routerrpc.SendToRouteRequest{
PaymentHash: hash[:],
Route: route,
}
// Dispatch in a goroutine because this call is blocking - we assume
// that we'll have assertions that this payment is sent by the caller.
go func() {
b.ht.Alice.RPC.SendToRouteV2(sendReq)
}()
}
// interceptFinalHop launches a goroutine to intercept Carol's htlcs and
// returns a closure that can be used to resolve intercepted htlcs.
//
//nolint:lll
func (b *blindedForwardTest) interceptFinalHop() func(routerrpc.ResolveHoldForwardAction) {
hash := sha256.Sum256(b.preimage[:])
htlcReceived := make(chan *routerrpc.ForwardHtlcInterceptRequest)
// Launch a goroutine which will receive from the interceptor and pipe
// it into our request channel.
go func() {
forward, err := b.carolInterceptor.Recv()
if err != nil {
b.ht.Fatalf("intercept receive failed: %v", err)
}
if !bytes.Equal(forward.PaymentHash, hash[:]) {
b.ht.Fatalf("unexpected payment hash: %v", hash)
}
select {
case htlcReceived <- forward:
case <-time.After(lntest.DefaultTimeout):
b.ht.Fatal("timeout waiting to send intercepted htlc")
}
}()
// Create a closure that will wait for the intercept request and
// resolve the HTLC with the appropriate action.
resolve := func(action routerrpc.ResolveHoldForwardAction) {
select {
case forward := <-htlcReceived:
resp := &routerrpc.ForwardHtlcInterceptResponse{
IncomingCircuitKey: forward.IncomingCircuitKey,
}
switch action {
case routerrpc.ResolveHoldForwardAction_FAIL:
resp.Action = routerrpc.ResolveHoldForwardAction_FAIL
case routerrpc.ResolveHoldForwardAction_SETTLE:
resp.Action = routerrpc.ResolveHoldForwardAction_SETTLE
resp.Preimage = b.preimage[:]
case routerrpc.ResolveHoldForwardAction_RESUME:
resp.Action = routerrpc.ResolveHoldForwardAction_RESUME
}
require.NoError(b.ht, b.carolInterceptor.Send(resp))
case <-time.After(lntest.DefaultTimeout):
b.ht.Fatal("timeout waiting for htlc intercept")
}
}
return resolve
}
// setupFourHopNetwork creates a network with the following topology and
// liquidity:
// Alice (100k)----- Bob (100k) ----- Carol (100k) ----- Dave
//
// The funding outpoint for AB / BC / CD are returned in-order.
func setupFourHopNetwork(ht *lntest.HarnessTest,
carol, dave *node.HarnessNode) []*lnrpc.ChannelPoint {
const chanAmt = btcutil.Amount(100000)
var networkChans []*lnrpc.ChannelPoint
// Open a channel with 100k satoshis between Alice and Bob with Alice
// being the sole funder of the channel.
chanPointAlice := ht.OpenChannel(
ht.Alice, ht.Bob, lntest.OpenChannelParams{
Amt: chanAmt,
},
)
networkChans = append(networkChans, chanPointAlice)
// Create a channel between bob and carol.
ht.EnsureConnected(ht.Bob, carol)
chanPointBob := ht.OpenChannel(
ht.Bob, carol, lntest.OpenChannelParams{
Amt: chanAmt,
},
)
networkChans = append(networkChans, chanPointBob)
// Fund carol and connect her and dave so that she can create a channel
// between them.
ht.FundCoins(btcutil.SatoshiPerBitcoin, carol)
ht.EnsureConnected(carol, dave)
chanPointCarol := ht.OpenChannel(
carol, dave, lntest.OpenChannelParams{
Amt: chanAmt,
},
)
networkChans = append(networkChans, chanPointCarol)
// Wait for all nodes to have seen all channels.
nodes := []*node.HarnessNode{ht.Alice, ht.Bob, carol, dave}
for _, chanPoint := range networkChans {
for _, node := range nodes {
ht.AssertTopologyChannelOpen(node, chanPoint)
}
}
return []*lnrpc.ChannelPoint{
chanPointAlice,
chanPointBob,
chanPointCarol,
}
}
// createBlindedRoute creates a blinded route to the recipient node provided.
// The set of hops is expected to start at the introduction node and end at
// the recipient.
func (b *blindedForwardTest) createBlindedRoute(hops []*forwardingEdge,
dest *btcec.PublicKey, finalCLTV uint16) *routing.BlindedPayment {
// Create a path with space for each of our hops + the destination
// node. We include our passed final cltv delta here because blinded
// paths include the delta in the blinded portion (not the invoice).
blindedPayment := &routing.BlindedPayment{
CltvExpiryDelta: finalCLTV,
}
pathLength := len(hops) + 1
blindedPath := make([]*sphinx.HopInfo, pathLength)
// Run forwards through our hops to create blinded route data for each
// node with the next node's short channel id and our payment
// constraints.
for i := 0; i < len(hops); i++ {
node := hops[i]
scid := node.channelID
// Set the relay information for this edge based on its policy.
delta := uint16(node.edge.TimeLockDelta)
relayInfo := &record.PaymentRelayInfo{
BaseFee: uint32(node.edge.FeeBaseMsat),
FeeRate: uint32(node.edge.FeeRateMilliMsat),
CltvExpiryDelta: delta,
}
// We set our constraints with our edge's actual htlc min, and
// an arbitrary maximum expiry (since it's just an anti-probing
// mechanism).
constraints := &record.PaymentConstraints{
HtlcMinimumMsat: lnwire.MilliSatoshi(node.edge.MinHtlc),
MaxCltvExpiry: 100000,
}
// Add CLTV delta of each hop to the blinded payment.
blindedPayment.CltvExpiryDelta += delta
// Encode the route's blinded data and include it in the
// blinded hop.
payload := record.NewBlindedRouteData(
scid, nil, *relayInfo, constraints, nil,
)
payloadBytes, err := record.EncodeBlindedRouteData(payload)
require.NoError(b.ht, err)
blindedPath[i] = &sphinx.HopInfo{
NodePub: node.pubkey,
PlainText: payloadBytes,
}
}
// Next, we'll run backwards through our route to build up the aggregate
// fees for the blinded payment as a whole. This is done in a separate
// loop for the sake of readability.
//
// For blinded path aggregated fees, we start at the receiving node
// and add up base an proportional fees *including* the fees that we'll
// charge on accumulated fees. We use the int ceiling to round up so
// that the sender will always over-pay, ensuring that we don't round
// down along the route leaving one forwarding node short of what
// they're expecting.
var (
hopCount = len(hops) - 1
currentHopBaseFee = hops[hopCount].edge.FeeBaseMsat
currentHopPropFee = hops[hopCount].edge.FeeRateMilliMsat
feeParts int64 = 1e6
)
// Note: the spec says to iterate backwards, but then uses n / n +1 to
// express the "next" hop in the route going backwards. This works for
// languages where we can iterate backwards and get an increasing
// index, but since we're counting backwards we use n-1 instead.
//
// Specification reference:
//nolint:lll
// https://github.com/lightning/bolts/blob/60de4a09727c20dea330f9ee8313034de6e50594/proposals/route-blinding.md?plain=1#L253-L254
for i := hopCount; i > 0; i-- {
preceedingBase := hops[i-1].edge.FeeBaseMsat
preceedingProp := hops[i-1].edge.FeeBaseMsat
// Separate numerator from ceiling division to break up large
// lines.
baseFeeNumerator := preceedingBase*feeParts +
currentHopBaseFee*(feeParts+preceedingProp)
currentHopBaseFee = (baseFeeNumerator + feeParts - 1) / feeParts
propFeeNumerator := (currentHopPropFee+preceedingProp)*
feeParts + currentHopPropFee*preceedingProp
currentHopPropFee = (propFeeNumerator + feeParts - 1) / feeParts
}
blindedPayment.BaseFee = uint32(currentHopBaseFee)
blindedPayment.ProportionalFeeRate = uint32(currentHopPropFee)
// Add our destination node at the end of the path. We don't need to
// add any forwarding parameters because we're at the final hop.
payloadBytes, err := record.EncodeBlindedRouteData(
// TODO: we don't have support for the final hop fields,
// because only forwarding is supported. We add a next
// node ID here so that it _looks like_ a valid
// forwarding hop (though in reality it's the last
// hop).
record.NewBlindedRouteData(
lnwire.NewShortChanIDFromInt(100), nil,
record.PaymentRelayInfo{}, nil, nil,
),
)
require.NoError(b.ht, err, "final payload")
blindedPath[pathLength-1] = &sphinx.HopInfo{
NodePub: dest,
PlainText: payloadBytes,
}
// Blind the path.
blindingKey, err := btcec.NewPrivateKey()
require.NoError(b.ht, err)
blindedPayment.BlindedPath, err = sphinx.BuildBlindedPath(
blindingKey, blindedPath,
)
require.NoError(b.ht, err, "build blinded path")
return blindedPayment
}
// forwardingEdge contains the channel id/source public key for a forwarding
// edge and the policy associated with the channel in that direction.
type forwardingEdge struct {
pubkey *btcec.PublicKey
channelID lnwire.ShortChannelID
edge *lnrpc.RoutingPolicy
}
func getForwardingEdge(ht *lntest.HarnessTest,
node *node.HarnessNode, chanID uint64) *forwardingEdge {
chanInfo := node.RPC.GetChanInfo(&lnrpc.ChanInfoRequest{
ChanId: chanID,
})
pubkey, err := btcec.ParsePubKey(node.PubKey[:])
require.NoError(ht, err, "%v pubkey", node.Cfg.Name)
fwdEdge := &forwardingEdge{
pubkey: pubkey,
channelID: lnwire.NewShortChanIDFromInt(chanID),
}
if chanInfo.Node1Pub == node.PubKeyStr {
fwdEdge.edge = chanInfo.Node1Policy
} else {
require.Equal(ht, node.PubKeyStr, chanInfo.Node2Pub,
"policy edge sanity check")
fwdEdge.edge = chanInfo.Node2Policy
}
return fwdEdge
}
// testForwardBlindedRoute tests lnd's ability to forward payments in a blinded
// route.
func testForwardBlindedRoute(ht *lntest.HarnessTest) {
ctx, testCase := newBlindedForwardTest(ht)
defer testCase.cleanup()
route := testCase.setup(ctx)
blindedRoute := testCase.createRouteToBlinded(10_000_000, route)
// Receiving via blinded routes is not yet supported, so Dave won't be
// able to process the payment.
//
// We have an interceptor at our disposal that will catch htlcs as they
// are forwarded (ie, it won't intercept a HTLC that dave is receiving,
// since no forwarding occurs). We initiate this interceptor with
// Carol, so that we can catch it and settle on the outgoing link to
// Dave. Once we hit the outgoing link, we know that we successfully
// parsed the htlc, so this is an acceptable compromise.
// Assert that our interceptor has exited without an error.
resolveHTLC := testCase.interceptFinalHop()
// Once our interceptor is set up, we can send the blinded payment.
testCase.sendBlindedPayment(ctx, blindedRoute)
// Wait for the HTLC to be active on Alice's channel.
hash := sha256.Sum256(testCase.preimage[:])
ht.AssertOutgoingHTLCActive(ht.Alice, testCase.channels[0], hash[:])
ht.AssertOutgoingHTLCActive(ht.Bob, testCase.channels[1], hash[:])
// Intercept and settle the HTLC.
resolveHTLC(routerrpc.ResolveHoldForwardAction_SETTLE)
// Wait for the HTLC to reflect as settled for Alice.
preimage, err := lntypes.MakePreimage(testCase.preimage[:])
require.NoError(ht, err)
ht.AssertPaymentStatus(ht.Alice, preimage, lnrpc.Payment_SUCCEEDED)
// Assert that the HTLC has settled before test cleanup runs so that
// we can cooperatively close all channels.
ht.AssertHTLCNotActive(ht.Bob, testCase.channels[1], hash[:])
ht.AssertHTLCNotActive(ht.Alice, testCase.channels[0], hash[:])
}