lnd.xprv/routing/pathfind_test.go
2019-03-15 10:08:32 +01:00

2024 lines
58 KiB
Go

package routing
import (
"bytes"
"crypto/sha256"
"encoding/binary"
"encoding/hex"
"encoding/json"
"errors"
"fmt"
"io/ioutil"
"math"
"math/big"
"net"
"os"
"strings"
"testing"
"github.com/btcsuite/btcd/btcec"
"github.com/btcsuite/btcd/chaincfg/chainhash"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/zpay32"
)
const (
// basicGraphFilePath is the file path for a basic graph used within
// the tests. The basic graph consists of 5 nodes with 5 channels
// connecting them.
basicGraphFilePath = "testdata/basic_graph.json"
// excessiveHopsGraphFilePath is a file path which stores the JSON dump
// of a graph which was previously triggering an erroneous excessive
// hops error. The error has since been fixed, but a test case
// exercising it is kept around to guard against regressions.
excessiveHopsGraphFilePath = "testdata/excessive_hops.json"
// specExampleFilePath is a file path which stores an example which
// implementations will use in order to ensure that they're calculating
// the payload for each hop in path properly.
specExampleFilePath = "testdata/spec_example.json"
// noFeeLimit is the maximum value of a payment through Lightning. We
// can use this value to signal there is no fee limit since payments
// should never be larger than this.
noFeeLimit = lnwire.MilliSatoshi(math.MaxUint32)
)
var (
noRestrictions = &RestrictParams{
FeeLimit: noFeeLimit,
}
)
var (
testSig = &btcec.Signature{
R: new(big.Int),
S: new(big.Int),
}
_, _ = testSig.R.SetString("63724406601629180062774974542967536251589935445068131219452686511677818569431", 10)
_, _ = testSig.S.SetString("18801056069249825825291287104931333862866033135609736119018462340006816851118", 10)
testAuthProof = channeldb.ChannelAuthProof{
NodeSig1Bytes: testSig.Serialize(),
NodeSig2Bytes: testSig.Serialize(),
BitcoinSig1Bytes: testSig.Serialize(),
BitcoinSig2Bytes: testSig.Serialize(),
}
)
// testGraph is the struct which corresponds to the JSON format used to encode
// graphs within the files in the testdata directory.
//
// TODO(roasbeef): add test graph auto-generator
type testGraph struct {
Info []string `json:"info"`
Nodes []testNode `json:"nodes"`
Edges []testChan `json:"edges"`
}
// testNode represents a node within the test graph above. We skip certain
// information such as the node's IP address as that information isn't needed
// for our tests.
type testNode struct {
Source bool `json:"source"`
PubKey string `json:"pubkey"`
Alias string `json:"alias"`
}
// testChan represents the JSON version of a payment channel. This struct
// matches the Json that's encoded under the "edges" key within the test graph.
type testChan struct {
Node1 string `json:"node_1"`
Node2 string `json:"node_2"`
ChannelID uint64 `json:"channel_id"`
ChannelPoint string `json:"channel_point"`
ChannelFlags uint8 `json:"channel_flags"`
MessageFlags uint8 `json:"message_flags"`
Expiry uint16 `json:"expiry"`
MinHTLC int64 `json:"min_htlc"`
MaxHTLC int64 `json:"max_htlc"`
FeeBaseMsat int64 `json:"fee_base_msat"`
FeeRate int64 `json:"fee_rate"`
Capacity int64 `json:"capacity"`
}
// makeTestGraph creates a new instance of a channeldb.ChannelGraph for testing
// purposes. A callback which cleans up the created temporary directories is
// also returned and intended to be executed after the test completes.
func makeTestGraph() (*channeldb.ChannelGraph, func(), error) {
// First, create a temporary directory to be used for the duration of
// this test.
tempDirName, err := ioutil.TempDir("", "channeldb")
if err != nil {
return nil, nil, err
}
// Next, create channeldb for the first time.
cdb, err := channeldb.Open(tempDirName)
if err != nil {
return nil, nil, err
}
cleanUp := func() {
cdb.Close()
os.RemoveAll(tempDirName)
}
return cdb.ChannelGraph(), cleanUp, nil
}
// parseTestGraph returns a fully populated ChannelGraph given a path to a JSON
// file which encodes a test graph.
func parseTestGraph(path string) (*testGraphInstance, error) {
graphJSON, err := ioutil.ReadFile(path)
if err != nil {
return nil, err
}
// First unmarshal the JSON graph into an instance of the testGraph
// struct. Using the struct tags created above in the struct, the JSON
// will be properly parsed into the struct above.
var g testGraph
if err := json.Unmarshal(graphJSON, &g); err != nil {
return nil, err
}
// We'll use this fake address for the IP address of all the nodes in
// our tests. This value isn't needed for path finding so it doesn't
// need to be unique.
var testAddrs []net.Addr
testAddr, err := net.ResolveTCPAddr("tcp", "192.0.0.1:8888")
if err != nil {
return nil, err
}
testAddrs = append(testAddrs, testAddr)
// Next, create a temporary graph database for usage within the test.
graph, cleanUp, err := makeTestGraph()
if err != nil {
return nil, err
}
aliasMap := make(map[string]Vertex)
var source *channeldb.LightningNode
// First we insert all the nodes within the graph as vertexes.
for _, node := range g.Nodes {
pubBytes, err := hex.DecodeString(node.PubKey)
if err != nil {
return nil, err
}
dbNode := &channeldb.LightningNode{
HaveNodeAnnouncement: true,
AuthSigBytes: testSig.Serialize(),
LastUpdate: testTime,
Addresses: testAddrs,
Alias: node.Alias,
Features: testFeatures,
}
copy(dbNode.PubKeyBytes[:], pubBytes)
// We require all aliases within the graph to be unique for our
// tests.
if _, ok := aliasMap[node.Alias]; ok {
return nil, errors.New("aliases for nodes " +
"must be unique!")
}
// If the alias is unique, then add the node to the
// alias map for easy lookup.
aliasMap[node.Alias] = dbNode.PubKeyBytes
// If the node is tagged as the source, then we create a
// pointer to is so we can mark the source in the graph
// properly.
if node.Source {
// If we come across a node that's marked as the
// source, and we've already set the source in a prior
// iteration, then the JSON has an error as only ONE
// node can be the source in the graph.
if source != nil {
return nil, errors.New("JSON is invalid " +
"multiple nodes are tagged as the source")
}
source = dbNode
}
// With the node fully parsed, add it as a vertex within the
// graph.
if err := graph.AddLightningNode(dbNode); err != nil {
return nil, err
}
}
if source != nil {
// Set the selected source node
if err := graph.SetSourceNode(source); err != nil {
return nil, err
}
}
// With all the vertexes inserted, we can now insert the edges into the
// test graph.
for _, edge := range g.Edges {
node1Bytes, err := hex.DecodeString(edge.Node1)
if err != nil {
return nil, err
}
node2Bytes, err := hex.DecodeString(edge.Node2)
if err != nil {
return nil, err
}
if bytes.Compare(node1Bytes, node2Bytes) == 1 {
return nil, fmt.Errorf(
"channel %v node order incorrect",
edge.ChannelID,
)
}
fundingTXID := strings.Split(edge.ChannelPoint, ":")[0]
txidBytes, err := chainhash.NewHashFromStr(fundingTXID)
if err != nil {
return nil, err
}
fundingPoint := wire.OutPoint{
Hash: *txidBytes,
Index: 0,
}
// We first insert the existence of the edge between the two
// nodes.
edgeInfo := channeldb.ChannelEdgeInfo{
ChannelID: edge.ChannelID,
AuthProof: &testAuthProof,
ChannelPoint: fundingPoint,
Capacity: btcutil.Amount(edge.Capacity),
}
copy(edgeInfo.NodeKey1Bytes[:], node1Bytes)
copy(edgeInfo.NodeKey2Bytes[:], node2Bytes)
copy(edgeInfo.BitcoinKey1Bytes[:], node1Bytes)
copy(edgeInfo.BitcoinKey2Bytes[:], node2Bytes)
err = graph.AddChannelEdge(&edgeInfo)
if err != nil && err != channeldb.ErrEdgeAlreadyExist {
return nil, err
}
edgePolicy := &channeldb.ChannelEdgePolicy{
SigBytes: testSig.Serialize(),
MessageFlags: lnwire.ChanUpdateMsgFlags(edge.MessageFlags),
ChannelFlags: lnwire.ChanUpdateChanFlags(edge.ChannelFlags),
ChannelID: edge.ChannelID,
LastUpdate: testTime,
TimeLockDelta: edge.Expiry,
MinHTLC: lnwire.MilliSatoshi(edge.MinHTLC),
MaxHTLC: lnwire.MilliSatoshi(edge.MaxHTLC),
FeeBaseMSat: lnwire.MilliSatoshi(edge.FeeBaseMsat),
FeeProportionalMillionths: lnwire.MilliSatoshi(edge.FeeRate),
}
if err := graph.UpdateEdgePolicy(edgePolicy); err != nil {
return nil, err
}
}
return &testGraphInstance{
graph: graph,
cleanUp: cleanUp,
aliasMap: aliasMap,
}, nil
}
type testChannelPolicy struct {
Expiry uint16
MinHTLC lnwire.MilliSatoshi
MaxHTLC lnwire.MilliSatoshi
FeeBaseMsat lnwire.MilliSatoshi
FeeRate lnwire.MilliSatoshi
}
type testChannelEnd struct {
Alias string
testChannelPolicy
}
func defaultTestChannelEnd(alias string, capacity btcutil.Amount) *testChannelEnd {
return &testChannelEnd{
Alias: alias,
testChannelPolicy: testChannelPolicy{
Expiry: 144,
MinHTLC: lnwire.MilliSatoshi(1000),
MaxHTLC: lnwire.NewMSatFromSatoshis(capacity),
FeeBaseMsat: lnwire.MilliSatoshi(1000),
FeeRate: lnwire.MilliSatoshi(1),
},
}
}
func symmetricTestChannel(alias1 string, alias2 string, capacity btcutil.Amount,
policy *testChannelPolicy, chanID ...uint64) *testChannel {
// Leaving id zero will result in auto-generation of a channel id during
// graph construction.
var id uint64
if len(chanID) > 0 {
id = chanID[0]
}
return &testChannel{
Capacity: capacity,
Node1: &testChannelEnd{
Alias: alias1,
testChannelPolicy: *policy,
},
Node2: &testChannelEnd{
Alias: alias2,
testChannelPolicy: *policy,
},
ChannelID: id,
}
}
type testChannel struct {
Node1 *testChannelEnd
Node2 *testChannelEnd
Capacity btcutil.Amount
ChannelID uint64
}
type testGraphInstance struct {
graph *channeldb.ChannelGraph
cleanUp func()
// aliasMap is a map from a node's alias to its public key. This type is
// provided in order to allow easily look up from the human memorable alias
// to an exact node's public key.
aliasMap map[string]Vertex
// privKeyMap maps a node alias to its private key. This is used to be
// able to mock a remote node's signing behaviour.
privKeyMap map[string]*btcec.PrivateKey
}
// createTestGraphFromChannels returns a fully populated ChannelGraph based on a set of
// test channels. Additional required information like keys are derived in
// a deterministical way and added to the channel graph. A list of nodes is
// not required and derived from the channel data. The goal is to keep
// instantiating a test channel graph as light weight as possible.
func createTestGraphFromChannels(testChannels []*testChannel) (*testGraphInstance, error) {
// We'll use this fake address for the IP address of all the nodes in
// our tests. This value isn't needed for path finding so it doesn't
// need to be unique.
var testAddrs []net.Addr
testAddr, err := net.ResolveTCPAddr("tcp", "192.0.0.1:8888")
if err != nil {
return nil, err
}
testAddrs = append(testAddrs, testAddr)
// Next, create a temporary graph database for usage within the test.
graph, cleanUp, err := makeTestGraph()
if err != nil {
return nil, err
}
aliasMap := make(map[string]Vertex)
privKeyMap := make(map[string]*btcec.PrivateKey)
nodeIndex := byte(0)
addNodeWithAlias := func(alias string) (*channeldb.LightningNode, error) {
keyBytes := make([]byte, 32)
keyBytes = []byte{
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, nodeIndex + 1,
}
privKey, pubKey := btcec.PrivKeyFromBytes(btcec.S256(),
keyBytes)
dbNode := &channeldb.LightningNode{
HaveNodeAnnouncement: true,
AuthSigBytes: testSig.Serialize(),
LastUpdate: testTime,
Addresses: testAddrs,
Alias: alias,
Features: testFeatures,
}
copy(dbNode.PubKeyBytes[:], pubKey.SerializeCompressed())
privKeyMap[alias] = privKey
// With the node fully parsed, add it as a vertex within the
// graph.
if err := graph.AddLightningNode(dbNode); err != nil {
return nil, err
}
aliasMap[alias] = dbNode.PubKeyBytes
nodeIndex++
return dbNode, nil
}
var source *channeldb.LightningNode
if source, err = addNodeWithAlias("roasbeef"); err != nil {
return nil, err
}
// Set the source node
if err := graph.SetSourceNode(source); err != nil {
return nil, err
}
// Initialize variable that keeps track of the next channel id to assign
// if none is specified.
nextUnassignedChannelID := uint64(100000)
for _, testChannel := range testChannels {
for _, alias := range []string{
testChannel.Node1.Alias, testChannel.Node2.Alias} {
_, exists := aliasMap[alias]
if !exists {
addNodeWithAlias(alias)
}
}
channelID := testChannel.ChannelID
// If no channel id is specified, generate an id.
if channelID == 0 {
channelID = nextUnassignedChannelID
nextUnassignedChannelID++
}
var hash [sha256.Size]byte
hash[len(hash)-1] = byte(channelID)
fundingPoint := &wire.OutPoint{
Hash: chainhash.Hash(hash),
Index: 0,
}
// We first insert the existence of the edge between the two
// nodes.
edgeInfo := channeldb.ChannelEdgeInfo{
ChannelID: channelID,
AuthProof: &testAuthProof,
ChannelPoint: *fundingPoint,
Capacity: testChannel.Capacity,
NodeKey1Bytes: aliasMap[testChannel.Node1.Alias],
BitcoinKey1Bytes: aliasMap[testChannel.Node1.Alias],
NodeKey2Bytes: aliasMap[testChannel.Node2.Alias],
BitcoinKey2Bytes: aliasMap[testChannel.Node2.Alias],
}
err = graph.AddChannelEdge(&edgeInfo)
if err != nil && err != channeldb.ErrEdgeAlreadyExist {
return nil, err
}
var msgFlags lnwire.ChanUpdateMsgFlags
if testChannel.Node1.MaxHTLC != 0 {
msgFlags = 1
}
edgePolicy := &channeldb.ChannelEdgePolicy{
SigBytes: testSig.Serialize(),
MessageFlags: msgFlags,
ChannelFlags: 0,
ChannelID: channelID,
LastUpdate: testTime,
TimeLockDelta: testChannel.Node1.Expiry,
MinHTLC: testChannel.Node1.MinHTLC,
MaxHTLC: testChannel.Node1.MaxHTLC,
FeeBaseMSat: testChannel.Node1.FeeBaseMsat,
FeeProportionalMillionths: testChannel.Node1.FeeRate,
}
if err := graph.UpdateEdgePolicy(edgePolicy); err != nil {
return nil, err
}
msgFlags = 0
if testChannel.Node2.MaxHTLC != 0 {
msgFlags = 1
}
edgePolicy = &channeldb.ChannelEdgePolicy{
SigBytes: testSig.Serialize(),
MessageFlags: msgFlags,
ChannelFlags: lnwire.ChanUpdateDirection,
ChannelID: channelID,
LastUpdate: testTime,
TimeLockDelta: testChannel.Node2.Expiry,
MinHTLC: testChannel.Node2.MinHTLC,
MaxHTLC: testChannel.Node2.MaxHTLC,
FeeBaseMSat: testChannel.Node2.FeeBaseMsat,
FeeProportionalMillionths: testChannel.Node2.FeeRate,
}
if err := graph.UpdateEdgePolicy(edgePolicy); err != nil {
return nil, err
}
channelID++
}
return &testGraphInstance{
graph: graph,
cleanUp: cleanUp,
aliasMap: aliasMap,
privKeyMap: privKeyMap,
}, nil
}
// TestFindLowestFeePath tests that out of two routes with identical total
// time lock values, the route with the lowest total fee should be returned.
// The fee rates are chosen such that the test failed on the previous edge
// weight function where one of the terms was fee squared.
func TestFindLowestFeePath(t *testing.T) {
t.Parallel()
// Set up a test graph with two paths from roasbeef to target. Both
// paths have equal total time locks, but the path through b has lower
// fees (700 compared to 800 for the path through a).
testChannels := []*testChannel{
symmetricTestChannel("roasbeef", "first", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: 100000000,
}),
symmetricTestChannel("first", "a", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: 100000000,
}),
symmetricTestChannel("a", "target", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: 100000000,
}),
symmetricTestChannel("first", "b", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 100,
MinHTLC: 1,
MaxHTLC: 100000000,
}),
symmetricTestChannel("b", "target", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 600,
MinHTLC: 1,
MaxHTLC: 100000000,
}),
}
testGraphInstance, err := createTestGraphFromChannels(testChannels)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer testGraphInstance.cleanUp()
sourceNode, err := testGraphInstance.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
sourceVertex := Vertex(sourceNode.PubKeyBytes)
const (
startingHeight = 100
finalHopCLTV = 1
)
paymentAmt := lnwire.NewMSatFromSatoshis(100)
target := testGraphInstance.aliasMap["target"]
path, err := findPath(
&graphParams{
graph: testGraphInstance.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, paymentAmt,
)
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
route, err := newRoute(
paymentAmt, sourceVertex, path, startingHeight,
finalHopCLTV)
if err != nil {
t.Fatalf("unable to create path: %v", err)
}
// Assert that the lowest fee route is returned.
if route.Hops[1].PubKeyBytes != testGraphInstance.aliasMap["b"] {
t.Fatalf("expected route to pass through b, "+
"but got a route through %v",
getAliasFromPubKey(route.Hops[1].PubKeyBytes,
testGraphInstance.aliasMap))
}
}
func getAliasFromPubKey(pubKey Vertex,
aliases map[string]Vertex) string {
for alias, key := range aliases {
if key == pubKey {
return alias
}
}
return ""
}
type expectedHop struct {
alias string
fee lnwire.MilliSatoshi
fwdAmount lnwire.MilliSatoshi
timeLock uint32
}
type basicGraphPathFindingTestCase struct {
target string
paymentAmt btcutil.Amount
feeLimit lnwire.MilliSatoshi
expectedTotalAmt lnwire.MilliSatoshi
expectedTotalTimeLock uint32
expectedHops []expectedHop
expectFailureNoPath bool
}
var basicGraphPathFindingTests = []basicGraphPathFindingTestCase{
// Basic route with one intermediate hop.
{target: "sophon", paymentAmt: 100, feeLimit: noFeeLimit,
expectedTotalTimeLock: 102, expectedTotalAmt: 100110,
expectedHops: []expectedHop{
{alias: "songoku", fwdAmount: 100000, fee: 110, timeLock: 101},
{alias: "sophon", fwdAmount: 100000, fee: 0, timeLock: 101},
}},
// Basic direct (one hop) route.
{target: "luoji", paymentAmt: 100, feeLimit: noFeeLimit,
expectedTotalTimeLock: 101, expectedTotalAmt: 100000,
expectedHops: []expectedHop{
{alias: "luoji", fwdAmount: 100000, fee: 0, timeLock: 101},
}},
// Three hop route where fees need to be added in to the forwarding amount.
// The high fee hop phamnewun should be avoided.
{target: "elst", paymentAmt: 50000, feeLimit: noFeeLimit,
expectedTotalTimeLock: 103, expectedTotalAmt: 50050210,
expectedHops: []expectedHop{
{alias: "songoku", fwdAmount: 50000200, fee: 50010, timeLock: 102},
{alias: "sophon", fwdAmount: 50000000, fee: 200, timeLock: 101},
{alias: "elst", fwdAmount: 50000000, fee: 0, timeLock: 101},
}},
// Three hop route where fees need to be added in to the forwarding amount.
// However this time the fwdAmount becomes too large for the roasbeef <->
// songoku channel. Then there is no other option than to choose the
// expensive phamnuwen channel. This test case was failing before
// the route search was executed backwards.
{target: "elst", paymentAmt: 100000, feeLimit: noFeeLimit,
expectedTotalTimeLock: 103, expectedTotalAmt: 110010220,
expectedHops: []expectedHop{
{alias: "phamnuwen", fwdAmount: 100000200, fee: 10010020, timeLock: 102},
{alias: "sophon", fwdAmount: 100000000, fee: 200, timeLock: 101},
{alias: "elst", fwdAmount: 100000000, fee: 0, timeLock: 101},
}},
// Basic route with fee limit.
{target: "sophon", paymentAmt: 100, feeLimit: 50,
expectFailureNoPath: true,
}}
func TestBasicGraphPathFinding(t *testing.T) {
t.Parallel()
testGraphInstance, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer testGraphInstance.cleanUp()
// With the test graph loaded, we'll test some basic path finding using
// the pre-generated graph. Consult the testdata/basic_graph.json file
// to follow along with the assumptions we'll use to test the path
// finding.
for _, testCase := range basicGraphPathFindingTests {
t.Run(testCase.target, func(subT *testing.T) {
testBasicGraphPathFindingCase(subT, testGraphInstance, &testCase)
})
}
}
func testBasicGraphPathFindingCase(t *testing.T, graphInstance *testGraphInstance,
test *basicGraphPathFindingTestCase) {
aliases := graphInstance.aliasMap
expectedHops := test.expectedHops
expectedHopCount := len(expectedHops)
sourceNode, err := graphInstance.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
sourceVertex := Vertex(sourceNode.PubKeyBytes)
const (
startingHeight = 100
finalHopCLTV = 1
)
paymentAmt := lnwire.NewMSatFromSatoshis(test.paymentAmt)
target := graphInstance.aliasMap[test.target]
path, err := findPath(
&graphParams{
graph: graphInstance.graph,
},
&RestrictParams{
FeeLimit: test.feeLimit,
},
sourceNode.PubKeyBytes, target, paymentAmt,
)
if test.expectFailureNoPath {
if err == nil {
t.Fatal("expected no path to be found")
}
return
}
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
route, err := newRoute(
paymentAmt, sourceVertex, path, startingHeight,
finalHopCLTV,
)
if err != nil {
t.Fatalf("unable to create path: %v", err)
}
if len(route.Hops) != len(expectedHops) {
t.Fatalf("route is of incorrect length, expected %v got %v",
expectedHopCount, len(route.Hops))
}
// Check hop nodes
for i := 0; i < len(expectedHops); i++ {
if route.Hops[i].PubKeyBytes != aliases[expectedHops[i].alias] {
t.Fatalf("%v-th hop should be %v, is instead: %v",
i, expectedHops[i],
getAliasFromPubKey(route.Hops[i].PubKeyBytes,
aliases))
}
}
// Next, we'll assert that the "next hop" field in each route payload
// properly points to the channel ID that the HTLC should be forwarded
// along.
hopPayloads := route.ToHopPayloads()
if len(hopPayloads) != expectedHopCount {
t.Fatalf("incorrect number of hop payloads: expected %v, got %v",
expectedHopCount, len(hopPayloads))
}
// Hops should point to the next hop
for i := 0; i < len(expectedHops)-1; i++ {
var expectedHop [8]byte
binary.BigEndian.PutUint64(expectedHop[:], route.Hops[i+1].ChannelID)
if !bytes.Equal(hopPayloads[i].NextAddress[:], expectedHop[:]) {
t.Fatalf("first hop has incorrect next hop: expected %x, got %x",
expectedHop[:], hopPayloads[i].NextAddress)
}
}
// The final hop should have a next hop value of all zeroes in order
// to indicate it's the exit hop.
var exitHop [8]byte
lastHopIndex := len(expectedHops) - 1
if !bytes.Equal(hopPayloads[lastHopIndex].NextAddress[:], exitHop[:]) {
t.Fatalf("first hop has incorrect next hop: expected %x, got %x",
exitHop[:], hopPayloads[lastHopIndex].NextAddress)
}
var expectedTotalFee lnwire.MilliSatoshi
for i := 0; i < expectedHopCount; i++ {
// We'll ensure that the amount to forward, and fees
// computed for each hop are correct.
fee := route.HopFee(i)
if fee != expectedHops[i].fee {
t.Fatalf("fee incorrect for hop %v: expected %v, got %v",
i, expectedHops[i].fee, fee)
}
if route.Hops[i].AmtToForward != expectedHops[i].fwdAmount {
t.Fatalf("forwarding amount for hop %v incorrect: "+
"expected %v, got %v",
i, expectedHops[i].fwdAmount,
route.Hops[i].AmtToForward)
}
// We'll also assert that the outgoing CLTV value for each
// hop was set accordingly.
if route.Hops[i].OutgoingTimeLock != expectedHops[i].timeLock {
t.Fatalf("outgoing time-lock for hop %v is incorrect: "+
"expected %v, got %v", i,
expectedHops[i].timeLock,
route.Hops[i].OutgoingTimeLock)
}
expectedTotalFee += expectedHops[i].fee
}
if route.TotalAmount != test.expectedTotalAmt {
t.Fatalf("total amount incorrect: "+
"expected %v, got %v",
test.expectedTotalAmt, route.TotalAmount)
}
if route.TotalTimeLock != test.expectedTotalTimeLock {
t.Fatalf("expected time lock of %v, instead have %v", 2,
route.TotalTimeLock)
}
}
func TestPathFindingWithAdditionalEdges(t *testing.T) {
t.Parallel()
graph, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
paymentAmt := lnwire.NewMSatFromSatoshis(100)
// In this test, we'll test that we're able to find paths through
// private channels when providing them as additional edges in our path
// finding algorithm. To do so, we'll create a new node, doge, and
// create a private channel between it and songoku. We'll then attempt
// to find a path from our source node, roasbeef, to doge.
dogePubKeyHex := "03dd46ff29a6941b4a2607525b043ec9b020b3f318a1bf281536fd7011ec59c882"
dogePubKeyBytes, err := hex.DecodeString(dogePubKeyHex)
if err != nil {
t.Fatalf("unable to decode public key: %v", err)
}
dogePubKey, err := btcec.ParsePubKey(dogePubKeyBytes, btcec.S256())
if err != nil {
t.Fatalf("unable to parse public key from bytes: %v", err)
}
doge := &channeldb.LightningNode{}
doge.AddPubKey(dogePubKey)
doge.Alias = "doge"
copy(doge.PubKeyBytes[:], dogePubKeyBytes)
graph.aliasMap["doge"] = doge.PubKeyBytes
// Create the channel edge going from songoku to doge and include it in
// our map of additional edges.
songokuToDoge := &channeldb.ChannelEdgePolicy{
Node: doge,
ChannelID: 1337,
FeeBaseMSat: 1,
FeeProportionalMillionths: 1000,
TimeLockDelta: 9,
}
additionalEdges := map[Vertex][]*channeldb.ChannelEdgePolicy{
graph.aliasMap["songoku"]: {songokuToDoge},
}
// We should now be able to find a path from roasbeef to doge.
path, err := findPath(
&graphParams{
graph: graph.graph,
additionalEdges: additionalEdges,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, doge.PubKeyBytes, paymentAmt,
)
if err != nil {
t.Fatalf("unable to find private path to doge: %v", err)
}
// The path should represent the following hops:
// roasbeef -> songoku -> doge
assertExpectedPath(t, graph.aliasMap, path, "songoku", "doge")
}
func TestKShortestPathFinding(t *testing.T) {
t.Parallel()
graph, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
// In this test we'd like to ensure that our algorithm to find the
// k-shortest paths from a given source node to any destination node
// works as expected.
// In our basic_graph.json, there exist two paths from roasbeef to luo
// ji. Our algorithm should properly find both paths, and also rank
// them in order of their total "distance".
paymentAmt := lnwire.NewMSatFromSatoshis(100)
target := graph.aliasMap["luoji"]
restrictions := &RestrictParams{
FeeLimit: noFeeLimit,
}
paths, err := findPaths(
nil, graph.graph, sourceNode.PubKeyBytes, target, paymentAmt,
restrictions, 100, nil,
)
if err != nil {
t.Fatalf("unable to find paths between roasbeef and "+
"luo ji: %v", err)
}
// The algorithm should have found two paths from roasbeef to luo ji.
if len(paths) != 2 {
t.Fatalf("two path shouldn't been found, instead %v were",
len(paths))
}
// Additionally, the total hop length of the first path returned should
// be _less_ than that of the second path returned.
if len(paths[0]) > len(paths[1]) {
t.Fatalf("paths found not ordered properly")
}
// The first route should be a direct route to luo ji.
assertExpectedPath(t, graph.aliasMap, paths[0], "roasbeef", "luoji")
// The second route should be a route to luo ji via satoshi.
assertExpectedPath(
t, graph.aliasMap, paths[1], "roasbeef", "satoshi", "luoji",
)
}
// TestNewRoute tests whether the construction of hop payloads by newRoute
// is executed correctly.
func TestNewRoute(t *testing.T) {
var sourceKey [33]byte
sourceVertex := Vertex(sourceKey)
const (
startingHeight = 100
finalHopCLTV = 1
)
createHop := func(baseFee lnwire.MilliSatoshi,
feeRate lnwire.MilliSatoshi,
bandwidth lnwire.MilliSatoshi,
timeLockDelta uint16) *channeldb.ChannelEdgePolicy {
return &channeldb.ChannelEdgePolicy{
Node: &channeldb.LightningNode{},
FeeProportionalMillionths: feeRate,
FeeBaseMSat: baseFee,
TimeLockDelta: timeLockDelta,
}
}
testCases := []struct {
// name identifies the test case in the test output.
name string
// hops is the list of hops (the route) that gets passed into
// the call to newRoute.
hops []*channeldb.ChannelEdgePolicy
// paymentAmount is the amount that is send into the route
// indicated by hops.
paymentAmount lnwire.MilliSatoshi
// expectedFees is a list of fees that every hop is expected
// to charge for forwarding.
expectedFees []lnwire.MilliSatoshi
// expectedTimeLocks is a list of time lock values that every
// hop is expected to specify in its outgoing HTLC. The time
// lock values in this list are relative to the current block
// height.
expectedTimeLocks []uint32
// expectedTotalAmount is the total amount that is expected to
// be returned from newRoute. This amount should include all
// the fees to be paid to intermediate hops.
expectedTotalAmount lnwire.MilliSatoshi
// expectedTotalTimeLock is the time lock that is expected to
// be returned from newRoute. This is the time lock that should
// be specified in the HTLC that is sent by the source node.
// expectedTotalTimeLock is relative to the current block height.
expectedTotalTimeLock uint32
// expectError indicates whether the newRoute call is expected
// to fail or succeed.
expectError bool
// expectedErrorCode indicates the expected error code when
// expectError is true.
expectedErrorCode errorCode
}{
{
// For a single hop payment, no fees are expected to be paid.
name: "single hop",
paymentAmount: 100000,
hops: []*channeldb.ChannelEdgePolicy{
createHop(100, 1000, 1000000, 10),
},
expectedFees: []lnwire.MilliSatoshi{0},
expectedTimeLocks: []uint32{1},
expectedTotalAmount: 100000,
expectedTotalTimeLock: 1,
}, {
// For a two hop payment, only the fee for the first hop
// needs to be paid. The destination hop does not require
// a fee to receive the payment.
name: "two hop",
paymentAmount: 100000,
hops: []*channeldb.ChannelEdgePolicy{
createHop(0, 1000, 1000000, 10),
createHop(30, 1000, 1000000, 5),
},
expectedFees: []lnwire.MilliSatoshi{130, 0},
expectedTimeLocks: []uint32{1, 1},
expectedTotalAmount: 100130,
expectedTotalTimeLock: 6,
}, {
// A three hop payment where the first and second hop
// will both charge 1 msat. The fee for the first hop
// is actually slightly higher than 1, because the amount
// to forward also includes the fee for the second hop. This
// gets rounded down to 1.
name: "three hop",
paymentAmount: 100000,
hops: []*channeldb.ChannelEdgePolicy{
createHop(0, 10, 1000000, 10),
createHop(0, 10, 1000000, 5),
createHop(0, 10, 1000000, 3),
},
expectedFees: []lnwire.MilliSatoshi{1, 1, 0},
expectedTotalAmount: 100002,
expectedTimeLocks: []uint32{4, 1, 1},
expectedTotalTimeLock: 9,
}, {
// A three hop payment where the fee of the first hop
// is slightly higher (11) than the fee at the second hop,
// because of the increase amount to forward.
name: "three hop with fee carry over",
paymentAmount: 100000,
hops: []*channeldb.ChannelEdgePolicy{
createHop(0, 10000, 1000000, 10),
createHop(0, 10000, 1000000, 5),
createHop(0, 10000, 1000000, 3),
},
expectedFees: []lnwire.MilliSatoshi{1010, 1000, 0},
expectedTotalAmount: 102010,
expectedTimeLocks: []uint32{4, 1, 1},
expectedTotalTimeLock: 9,
}, {
// A three hop payment where the fee policies of the first and
// second hop are just high enough to show the fee carry over
// effect.
name: "three hop with minimal fees for carry over",
paymentAmount: 100000,
hops: []*channeldb.ChannelEdgePolicy{
createHop(0, 10000, 1000000, 10),
// First hop charges 0.1% so the second hop fee
// should show up in the first hop fee as 1 msat
// extra.
createHop(0, 1000, 1000000, 5),
// Second hop charges a fixed 1000 msat.
createHop(1000, 0, 1000000, 3),
},
expectedFees: []lnwire.MilliSatoshi{101, 1000, 0},
expectedTotalAmount: 101101,
expectedTimeLocks: []uint32{4, 1, 1},
expectedTotalTimeLock: 9,
}}
for _, testCase := range testCases {
assertRoute := func(t *testing.T, route *Route) {
if route.TotalAmount != testCase.expectedTotalAmount {
t.Errorf("Expected total amount is be %v"+
", but got %v instead",
testCase.expectedTotalAmount,
route.TotalAmount)
}
for i := 0; i < len(testCase.expectedFees); i++ {
fee := route.HopFee(i)
if testCase.expectedFees[i] != fee {
t.Errorf("Expected fee for hop %v to "+
"be %v, but got %v instead",
i, testCase.expectedFees[i],
fee)
}
}
expectedTimeLockHeight := startingHeight +
testCase.expectedTotalTimeLock
if route.TotalTimeLock != expectedTimeLockHeight {
t.Errorf("Expected total time lock to be %v"+
", but got %v instead",
expectedTimeLockHeight,
route.TotalTimeLock)
}
for i := 0; i < len(testCase.expectedTimeLocks); i++ {
expectedTimeLockHeight := startingHeight +
testCase.expectedTimeLocks[i]
if expectedTimeLockHeight !=
route.Hops[i].OutgoingTimeLock {
t.Errorf("Expected time lock for hop "+
"%v to be %v, but got %v instead",
i, expectedTimeLockHeight,
route.Hops[i].OutgoingTimeLock)
}
}
}
t.Run(testCase.name, func(t *testing.T) {
route, err := newRoute(testCase.paymentAmount,
sourceVertex, testCase.hops, startingHeight,
finalHopCLTV)
if testCase.expectError {
expectedCode := testCase.expectedErrorCode
if err == nil || !IsError(err, expectedCode) {
t.Fatalf("expected newRoute to fail "+
"with error code %v but got "+
"%v instead",
expectedCode, err)
}
} else {
if err != nil {
t.Errorf("unable to create path: %v", err)
return
}
assertRoute(t, route)
}
})
}
}
func TestNewRoutePathTooLong(t *testing.T) {
t.Skip()
// Ensure that potential paths which are over the maximum hop-limit are
// rejected.
graph, err := parseTestGraph(excessiveHopsGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
paymentAmt := lnwire.NewMSatFromSatoshis(100)
// We start by confirming that routing a payment 20 hops away is
// possible. Alice should be able to find a valid route to ursula.
target := graph.aliasMap["ursula"]
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, paymentAmt,
)
if err != nil {
t.Fatalf("path should have been found")
}
// Vincent is 21 hops away from Alice, and thus no valid route should be
// presented to Alice.
target = graph.aliasMap["vincent"]
path, err := findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, paymentAmt,
)
if err == nil {
t.Fatalf("should not have been able to find path, supposed to be "+
"greater than 20 hops, found route with %v hops",
len(path))
}
}
func TestPathNotAvailable(t *testing.T) {
t.Parallel()
graph, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
// With the test graph loaded, we'll test that queries for target that
// are either unreachable within the graph, or unknown result in an
// error.
unknownNodeStr := "03dd46ff29a6941b4a2607525b043ec9b020b3f318a1bf281536fd7011ec59c882"
unknownNodeBytes, err := hex.DecodeString(unknownNodeStr)
if err != nil {
t.Fatalf("unable to parse bytes: %v", err)
}
var unknownNode Vertex
copy(unknownNode[:], unknownNodeBytes)
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, unknownNode, 100,
)
if !IsError(err, ErrNoPathFound) {
t.Fatalf("path shouldn't have been found: %v", err)
}
}
func TestPathInsufficientCapacity(t *testing.T) {
t.Parallel()
graph, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
// Next, test that attempting to find a path in which the current
// channel graph cannot support due to insufficient capacity triggers
// an error.
// To test his we'll attempt to make a payment of 1 BTC, or 100 million
// satoshis. The largest channel in the basic graph is of size 100k
// satoshis, so we shouldn't be able to find a path to sophon even
// though we have a 2-hop link.
target := graph.aliasMap["sophon"]
payAmt := lnwire.NewMSatFromSatoshis(btcutil.SatoshiPerBitcoin)
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if !IsError(err, ErrNoPathFound) {
t.Fatalf("graph shouldn't be able to support payment: %v", err)
}
}
// TestRouteFailMinHTLC tests that if we attempt to route an HTLC which is
// smaller than the advertised minHTLC of an edge, then path finding fails.
func TestRouteFailMinHTLC(t *testing.T) {
t.Parallel()
graph, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
// We'll not attempt to route an HTLC of 10 SAT from roasbeef to Son
// Goku. However, the min HTLC of Son Goku is 1k SAT, as a result, this
// attempt should fail.
target := graph.aliasMap["songoku"]
payAmt := lnwire.MilliSatoshi(10)
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if !IsError(err, ErrNoPathFound) {
t.Fatalf("graph shouldn't be able to support payment: %v", err)
}
}
// TestRouteFailMaxHTLC tests that if we attempt to route an HTLC which is
// larger than the advertised max HTLC of an edge, then path finding fails.
func TestRouteFailMaxHTLC(t *testing.T) {
t.Parallel()
// Set up a test graph:
// roasbeef <--> firstHop <--> secondHop <--> target
// We will be adjusting the max HTLC of the edge between the first and
// second hops.
var firstToSecondID uint64 = 1
testChannels := []*testChannel{
symmetricTestChannel("roasbeef", "first", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: 100000001,
}),
symmetricTestChannel("first", "second", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: 100000002,
}, firstToSecondID),
symmetricTestChannel("second", "target", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: 100000003,
}),
}
graph, err := createTestGraphFromChannels(testChannels)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
// First, attempt to send a payment greater than the max HTLC we are
// about to set, which should succeed.
target := graph.aliasMap["target"]
payAmt := lnwire.MilliSatoshi(100001)
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if err != nil {
t.Fatalf("graph should've been able to support payment: %v", err)
}
// Next, update the middle edge policy to only allow payments up to 100k
// msat.
_, midEdge, _, err := graph.graph.FetchChannelEdgesByID(firstToSecondID)
midEdge.MessageFlags = 1
midEdge.MaxHTLC = payAmt - 1
if err := graph.graph.UpdateEdgePolicy(midEdge); err != nil {
t.Fatalf("unable to update edge: %v", err)
}
// We'll now attempt to route through that edge with a payment above
// 100k msat, which should fail.
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if !IsError(err, ErrNoPathFound) {
t.Fatalf("graph shouldn't be able to support payment: %v", err)
}
}
// TestRouteFailDisabledEdge tests that if we attempt to route to an edge
// that's disabled, then that edge is disqualified, and the routing attempt
// will fail. We also test that this is true only for non-local edges, as we'll
// ignore the disable flags, with the assumption that the correct bandwidth is
// found among the bandwidth hints.
func TestRouteFailDisabledEdge(t *testing.T) {
t.Parallel()
graph, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
// First, we'll try to route from roasbeef -> sophon. This should
// succeed without issue, and return a single path via phamnuwen
target := graph.aliasMap["sophon"]
payAmt := lnwire.NewMSatFromSatoshis(105000)
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
// Disable the edge roasbeef->phamnuwen. This should not impact the
// path finding, as we don't consider the disable flag for local
// channels (and roasbeef is the source).
roasToPham := uint64(999991)
_, e1, e2, err := graph.graph.FetchChannelEdgesByID(roasToPham)
if err != nil {
t.Fatalf("unable to fetch edge: %v", err)
}
e1.ChannelFlags |= lnwire.ChanUpdateDisabled
if err := graph.graph.UpdateEdgePolicy(e1); err != nil {
t.Fatalf("unable to update edge: %v", err)
}
e2.ChannelFlags |= lnwire.ChanUpdateDisabled
if err := graph.graph.UpdateEdgePolicy(e2); err != nil {
t.Fatalf("unable to update edge: %v", err)
}
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
// Now, we'll modify the edge from phamnuwen -> sophon, to read that
// it's disabled.
phamToSophon := uint64(99999)
_, e, _, err := graph.graph.FetchChannelEdgesByID(phamToSophon)
if err != nil {
t.Fatalf("unable to fetch edge: %v", err)
}
e.ChannelFlags |= lnwire.ChanUpdateDisabled
if err := graph.graph.UpdateEdgePolicy(e); err != nil {
t.Fatalf("unable to update edge: %v", err)
}
// If we attempt to route through that edge, we should get a failure as
// it is no longer eligible.
_, err = findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if !IsError(err, ErrNoPathFound) {
t.Fatalf("graph shouldn't be able to support payment: %v", err)
}
}
// TestPathSourceEdgesBandwidth tests that explicitly passing in a set of
// bandwidth hints is used by the path finding algorithm to consider whether to
// use a local channel.
func TestPathSourceEdgesBandwidth(t *testing.T) {
t.Parallel()
graph, err := parseTestGraph(basicGraphFilePath)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer graph.cleanUp()
sourceNode, err := graph.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
// First, we'll try to route from roasbeef -> sophon. This should
// succeed without issue, and return a path via songoku, as that's the
// cheapest path.
target := graph.aliasMap["sophon"]
payAmt := lnwire.NewMSatFromSatoshis(50000)
path, err := findPath(
&graphParams{
graph: graph.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
assertExpectedPath(t, graph.aliasMap, path, "songoku", "sophon")
// Now we'll set the bandwidth of the edge roasbeef->songoku and
// roasbeef->phamnuwen to 0.
roasToSongoku := uint64(12345)
roasToPham := uint64(999991)
bandwidths := map[uint64]lnwire.MilliSatoshi{
roasToSongoku: 0,
roasToPham: 0,
}
// Since both these edges has a bandwidth of zero, no path should be
// found.
_, err = findPath(
&graphParams{
graph: graph.graph,
bandwidthHints: bandwidths,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if !IsError(err, ErrNoPathFound) {
t.Fatalf("graph shouldn't be able to support payment: %v", err)
}
// Set the bandwidth of roasbeef->phamnuwen high enough to carry the
// payment.
bandwidths[roasToPham] = 2 * payAmt
// Now, if we attempt to route again, we should find the path via
// phamnuven, as the other source edge won't be considered.
path, err = findPath(
&graphParams{
graph: graph.graph,
bandwidthHints: bandwidths,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
assertExpectedPath(t, graph.aliasMap, path, "phamnuwen", "sophon")
// Finally, set the roasbeef->songoku bandwidth, but also set its
// disable flag.
bandwidths[roasToSongoku] = 2 * payAmt
_, e1, e2, err := graph.graph.FetchChannelEdgesByID(roasToSongoku)
if err != nil {
t.Fatalf("unable to fetch edge: %v", err)
}
e1.ChannelFlags |= lnwire.ChanUpdateDisabled
if err := graph.graph.UpdateEdgePolicy(e1); err != nil {
t.Fatalf("unable to update edge: %v", err)
}
e2.ChannelFlags |= lnwire.ChanUpdateDisabled
if err := graph.graph.UpdateEdgePolicy(e2); err != nil {
t.Fatalf("unable to update edge: %v", err)
}
// Since we ignore disable flags for local channels, a path should
// still be found.
path, err = findPath(
&graphParams{
graph: graph.graph,
bandwidthHints: bandwidths,
},
&RestrictParams{
FeeLimit: noFeeLimit,
},
sourceNode.PubKeyBytes, target, payAmt,
)
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
assertExpectedPath(t, graph.aliasMap, path, "songoku", "sophon")
}
func TestPathInsufficientCapacityWithFee(t *testing.T) {
t.Parallel()
// TODO(roasbeef): encode live graph to json
// TODO(roasbeef): need to add a case, or modify the fee ratio for one
// to ensure that has going forward, but when fees are applied doesn't
// work
}
func TestPathFindSpecExample(t *testing.T) {
t.Parallel()
// All our path finding tests will assume a starting height of 100, so
// we'll pass that in to ensure that the router uses 100 as the current
// height.
const startingHeight = 100
ctx, cleanUp, err := createTestCtxFromFile(startingHeight, specExampleFilePath)
if err != nil {
t.Fatalf("unable to create router: %v", err)
}
defer cleanUp()
const (
aliceFinalCLTV = 10
bobFinalCLTV = 20
carolFinalCLTV = 30
daveFinalCLTV = 40
)
// We'll first exercise the scenario of a direct payment from Bob to
// Carol, so we set "B" as the source node so path finding starts from
// Bob.
bob := ctx.aliases["B"]
bobKey, err := btcec.ParsePubKey(bob[:], btcec.S256())
if err != nil {
t.Fatal(err)
}
bobNode, err := ctx.graph.FetchLightningNode(bobKey)
if err != nil {
t.Fatalf("unable to find bob: %v", err)
}
if err := ctx.graph.SetSourceNode(bobNode); err != nil {
t.Fatalf("unable to set source node: %v", err)
}
// Query for a route of 4,999,999 mSAT to carol.
carol := ctx.aliases["C"]
const amt lnwire.MilliSatoshi = 4999999
routes, err := ctx.router.FindRoutes(
bobNode.PubKeyBytes, carol, amt, noRestrictions, 100,
)
if err != nil {
t.Fatalf("unable to find route: %v", err)
}
// We should come back with _exactly_ two routes.
if len(routes) != 2 {
t.Fatalf("expected %v routes, instead have: %v", 2,
len(routes))
}
// Now we'll examine the first route returned for correctness.
//
// It should be sending the exact payment amount as there are no
// additional hops.
firstRoute := routes[0]
if firstRoute.TotalAmount != amt {
t.Fatalf("wrong total amount: got %v, expected %v",
firstRoute.TotalAmount, amt)
}
if firstRoute.Hops[0].AmtToForward != amt {
t.Fatalf("wrong forward amount: got %v, expected %v",
firstRoute.Hops[0].AmtToForward, amt)
}
fee := firstRoute.HopFee(0)
if fee != 0 {
t.Fatalf("wrong hop fee: got %v, expected %v", fee, 0)
}
// The CLTV expiry should be the current height plus 9 (the expiry for
// the B -> C channel.
if firstRoute.TotalTimeLock !=
startingHeight+zpay32.DefaultFinalCLTVDelta {
t.Fatalf("wrong total time lock: got %v, expecting %v",
firstRoute.TotalTimeLock,
startingHeight+zpay32.DefaultFinalCLTVDelta)
}
// Next, we'll set A as the source node so we can assert that we create
// the proper route for any queries starting with Alice.
alice := ctx.aliases["A"]
aliceKey, err := btcec.ParsePubKey(alice[:], btcec.S256())
if err != nil {
t.Fatal(err)
}
aliceNode, err := ctx.graph.FetchLightningNode(aliceKey)
if err != nil {
t.Fatalf("unable to find alice: %v", err)
}
if err := ctx.graph.SetSourceNode(aliceNode); err != nil {
t.Fatalf("unable to set source node: %v", err)
}
ctx.router.selfNode = aliceNode
source, err := ctx.graph.SourceNode()
if err != nil {
t.Fatalf("unable to retrieve source node: %v", err)
}
if source.PubKeyBytes != alice {
t.Fatalf("source node not set")
}
// We'll now request a route from A -> B -> C.
ctx.router.routeCache = make(map[routeTuple][]*Route)
routes, err = ctx.router.FindRoutes(
source.PubKeyBytes, carol, amt, noRestrictions, 100,
)
if err != nil {
t.Fatalf("unable to find routes: %v", err)
}
// We should come back with _exactly_ two routes.
if len(routes) != 2 {
t.Fatalf("expected %v routes, instead have: %v", 2,
len(routes))
}
// Both routes should be two hops.
if len(routes[0].Hops) != 2 {
t.Fatalf("route should be %v hops, is instead %v", 2,
len(routes[0].Hops))
}
if len(routes[1].Hops) != 2 {
t.Fatalf("route should be %v hops, is instead %v", 2,
len(routes[1].Hops))
}
// The total amount should factor in a fee of 10199 and also use a CLTV
// delta total of 29 (20 + 9),
expectedAmt := lnwire.MilliSatoshi(5010198)
if routes[0].TotalAmount != expectedAmt {
t.Fatalf("wrong amount: got %v, expected %v",
routes[0].TotalAmount, expectedAmt)
}
if routes[0].TotalTimeLock != startingHeight+29 {
t.Fatalf("wrong total time lock: got %v, expecting %v",
routes[0].TotalTimeLock, startingHeight+29)
}
// Ensure that the hops of the first route are properly crafted.
//
// After taking the fee, Bob should be forwarding the remainder which
// is the exact payment to Bob.
if routes[0].Hops[0].AmtToForward != amt {
t.Fatalf("wrong forward amount: got %v, expected %v",
routes[0].Hops[0].AmtToForward, amt)
}
// We shouldn't pay any fee for the first, hop, but the fee for the
// second hop posted fee should be exactly:
// The fee that we pay for the second hop will be "applied to the first
// hop, so we should get a fee of exactly:
//
// * 200 + 4999999 * 2000 / 1000000 = 10199
fee = routes[0].HopFee(0)
if fee != 10199 {
t.Fatalf("wrong hop fee: got %v, expected %v", fee, 10199)
}
// While for the final hop, as there's no additional hop afterwards, we
// pay no fee.
fee = routes[0].HopFee(1)
if fee != 0 {
t.Fatalf("wrong hop fee: got %v, expected %v", fee, 0)
}
// The outgoing CLTV value itself should be the current height plus 30
// to meet Carol's requirements.
if routes[0].Hops[0].OutgoingTimeLock !=
startingHeight+zpay32.DefaultFinalCLTVDelta {
t.Fatalf("wrong total time lock: got %v, expecting %v",
routes[0].Hops[0].OutgoingTimeLock,
startingHeight+zpay32.DefaultFinalCLTVDelta)
}
// For B -> C, we assert that the final hop also has the proper
// parameters.
lastHop := routes[0].Hops[1]
if lastHop.AmtToForward != amt {
t.Fatalf("wrong forward amount: got %v, expected %v",
lastHop.AmtToForward, amt)
}
if lastHop.OutgoingTimeLock !=
startingHeight+zpay32.DefaultFinalCLTVDelta {
t.Fatalf("wrong total time lock: got %v, expecting %v",
lastHop.OutgoingTimeLock,
startingHeight+zpay32.DefaultFinalCLTVDelta)
}
// We'll also make similar assertions for the second route from A to C
// via D.
secondRoute := routes[1]
expectedAmt = 5020398
if secondRoute.TotalAmount != expectedAmt {
t.Fatalf("wrong amount: got %v, expected %v",
secondRoute.TotalAmount, expectedAmt)
}
expectedTimeLock := startingHeight + daveFinalCLTV + zpay32.DefaultFinalCLTVDelta
if secondRoute.TotalTimeLock != uint32(expectedTimeLock) {
t.Fatalf("wrong total time lock: got %v, expecting %v",
secondRoute.TotalTimeLock, expectedTimeLock)
}
onionPayload := secondRoute.Hops[0]
if onionPayload.AmtToForward != amt {
t.Fatalf("wrong forward amount: got %v, expected %v",
onionPayload.AmtToForward, amt)
}
expectedTimeLock = startingHeight + zpay32.DefaultFinalCLTVDelta
if onionPayload.OutgoingTimeLock != uint32(expectedTimeLock) {
t.Fatalf("wrong outgoing time lock: got %v, expecting %v",
onionPayload.OutgoingTimeLock,
expectedTimeLock)
}
// The B -> C hop should also be identical as the prior cases.
lastHop = secondRoute.Hops[1]
if lastHop.AmtToForward != amt {
t.Fatalf("wrong forward amount: got %v, expected %v",
lastHop.AmtToForward, amt)
}
if lastHop.OutgoingTimeLock !=
startingHeight+zpay32.DefaultFinalCLTVDelta {
t.Fatalf("wrong total time lock: got %v, expecting %v",
lastHop.OutgoingTimeLock,
startingHeight+zpay32.DefaultFinalCLTVDelta)
}
}
func assertExpectedPath(t *testing.T, aliasMap map[string]Vertex,
path []*channeldb.ChannelEdgePolicy, nodeAliases ...string) {
if len(path) != len(nodeAliases) {
t.Fatal("number of hops and number of aliases do not match")
}
for i, hop := range path {
if hop.Node.PubKeyBytes != aliasMap[nodeAliases[i]] {
t.Fatalf("expected %v to be pos #%v in hop, instead "+
"%v was", nodeAliases[i], i, hop.Node.Alias)
}
}
}
// TestNewRouteFromEmptyHops tests that the NewRouteFromHops function returns an
// error when the hop list is empty.
func TestNewRouteFromEmptyHops(t *testing.T) {
t.Parallel()
var source Vertex
_, err := NewRouteFromHops(0, 0, source, []*Hop{})
if err != ErrNoRouteHopsProvided {
t.Fatalf("expected empty hops error: instead got: %v", err)
}
}
// TestRestrictOutgoingChannel asserts that a outgoing channel restriction is
// obeyed by the path finding algorithm.
func TestRestrictOutgoingChannel(t *testing.T) {
t.Parallel()
// Set up a test graph with three possible paths from roasbeef to
// target. The path through channel 2 is the highest cost path.
testChannels := []*testChannel{
symmetricTestChannel("roasbeef", "a", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
}, 1),
symmetricTestChannel("a", "target", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
}),
symmetricTestChannel("roasbeef", "b", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 800,
MinHTLC: 1,
}, 2),
symmetricTestChannel("roasbeef", "b", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 600,
MinHTLC: 1,
}, 3),
symmetricTestChannel("b", "target", 100000, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
}),
}
testGraphInstance, err := createTestGraphFromChannels(testChannels)
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer testGraphInstance.cleanUp()
sourceNode, err := testGraphInstance.graph.SourceNode()
if err != nil {
t.Fatalf("unable to fetch source node: %v", err)
}
sourceVertex := Vertex(sourceNode.PubKeyBytes)
const (
startingHeight = 100
finalHopCLTV = 1
)
paymentAmt := lnwire.NewMSatFromSatoshis(100)
target := testGraphInstance.aliasMap["target"]
outgoingChannelID := uint64(2)
// Find the best path given the restriction to only use channel 2 as the
// outgoing channel.
path, err := findPath(
&graphParams{
graph: testGraphInstance.graph,
},
&RestrictParams{
FeeLimit: noFeeLimit,
OutgoingChannelID: &outgoingChannelID,
},
sourceVertex, target, paymentAmt,
)
if err != nil {
t.Fatalf("unable to find path: %v", err)
}
route, err := newRoute(
paymentAmt, sourceVertex, path, startingHeight,
finalHopCLTV,
)
if err != nil {
t.Fatalf("unable to create path: %v", err)
}
// Assert that the route starts with channel 2, in line with the
// specified restriction.
if route.Hops[0].ChannelID != 2 {
t.Fatalf("expected route to pass through channel 2, "+
"but channel %v was selected instead", route.Hops[0].ChannelID)
}
}