lnd/autopilot/graph.go
Elle Mouton fa7c1e250b
multi: let ForEachChannel be a method on ChannelGraph
Having a `ForEachChannel` method on the `LightningNode` struct itself
results in a `kvdb.Backend` object needing to be stored within the
LightningNode struct. In this commit, this method is replaced with a
`ForEachNodeChannel` method on the `ChannelGraph` struct will perform
the same function without needing the db pointer to be stored within the
LightningNode. This change, the LightningNode struct more closely
represents the schema on disk.

The existing `ForEachNodeChannel` method on `ChannelGraph` is renamed to
`ForEachNodeDirectedChannel`. It performs a slightly different function
since it's call-back operates on Cached policies.
2023-11-08 10:51:50 +02:00

627 lines
16 KiB
Go

package autopilot
import (
"bytes"
"encoding/hex"
"net"
"sort"
"sync/atomic"
"time"
"github.com/btcsuite/btcd/btcec/v2"
"github.com/btcsuite/btcd/btcec/v2/ecdsa"
"github.com/btcsuite/btcd/btcutil"
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/kvdb"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/routing/route"
)
var (
testRBytes, _ = hex.DecodeString("8ce2bc69281ce27da07e6683571319d18e949ddfa2965fb6caa1bf0314f882d7")
testSBytes, _ = hex.DecodeString("299105481d63e0f4bc2a88121167221b6700d72a0ead154c03be696a292d24ae")
testRScalar = new(btcec.ModNScalar)
testSScalar = new(btcec.ModNScalar)
_ = testRScalar.SetByteSlice(testRBytes)
_ = testSScalar.SetByteSlice(testSBytes)
testSig = ecdsa.NewSignature(testRScalar, testSScalar)
chanIDCounter uint64 // To be used atomically.
)
// databaseChannelGraph wraps a channeldb.ChannelGraph instance with the
// necessary API to properly implement the autopilot.ChannelGraph interface.
//
// TODO(roasbeef): move inmpl to main package?
type databaseChannelGraph struct {
db *channeldb.ChannelGraph
}
// A compile time assertion to ensure databaseChannelGraph meets the
// autopilot.ChannelGraph interface.
var _ ChannelGraph = (*databaseChannelGraph)(nil)
// ChannelGraphFromDatabase returns an instance of the autopilot.ChannelGraph
// backed by a live, open channeldb instance.
func ChannelGraphFromDatabase(db *channeldb.ChannelGraph) ChannelGraph {
return &databaseChannelGraph{
db: db,
}
}
// type dbNode is a wrapper struct around a database transaction an
// channeldb.LightningNode. The wrapper method implement the autopilot.Node
// interface.
type dbNode struct {
db *channeldb.ChannelGraph
tx kvdb.RTx
node *channeldb.LightningNode
}
// A compile time assertion to ensure dbNode meets the autopilot.Node
// interface.
var _ Node = (*dbNode)(nil)
// PubKey is the identity public key of the node. This will be used to attempt
// to target a node for channel opening by the main autopilot agent. The key
// will be returned in serialized compressed format.
//
// NOTE: Part of the autopilot.Node interface.
func (d dbNode) PubKey() [33]byte {
return d.node.PubKeyBytes
}
// Addrs returns a slice of publicly reachable public TCP addresses that the
// peer is known to be listening on.
//
// NOTE: Part of the autopilot.Node interface.
func (d dbNode) Addrs() []net.Addr {
return d.node.Addresses
}
// ForEachChannel is a higher-order function that will be used to iterate
// through all edges emanating from/to the target node. For each active
// channel, this function should be called with the populated ChannelEdge that
// describes the active channel.
//
// NOTE: Part of the autopilot.Node interface.
func (d dbNode) ForEachChannel(cb func(ChannelEdge) error) error {
return d.db.ForEachNodeChannel(d.tx, d.node.PubKeyBytes,
func(tx kvdb.RTx, ei *channeldb.ChannelEdgeInfo, ep,
_ *channeldb.ChannelEdgePolicy) error {
// Skip channels for which no outgoing edge policy is
// available.
//
// TODO(joostjager): Ideally the case where channels
// have a nil policy should be supported, as autopilot
// is not looking at the policies. For now, it is not
// easily possible to get a reference to the other end
// LightningNode object without retrieving the policy.
if ep == nil {
return nil
}
edge := ChannelEdge{
ChanID: lnwire.NewShortChanIDFromInt(
ep.ChannelID,
),
Capacity: ei.Capacity,
Peer: dbNode{
tx: tx,
db: d.db,
node: ep.Node,
},
}
return cb(edge)
})
}
// ForEachNode is a higher-order function that should be called once for each
// connected node within the channel graph. If the passed callback returns an
// error, then execution should be terminated.
//
// NOTE: Part of the autopilot.ChannelGraph interface.
func (d *databaseChannelGraph) ForEachNode(cb func(Node) error) error {
return d.db.ForEachNode(func(tx kvdb.RTx, n *channeldb.LightningNode) error {
// We'll skip over any node that doesn't have any advertised
// addresses. As we won't be able to reach them to actually
// open any channels.
if len(n.Addresses) == 0 {
return nil
}
node := dbNode{
db: d.db,
tx: tx,
node: n,
}
return cb(node)
})
}
// addRandChannel creates a new channel two target nodes. This function is
// meant to aide in the generation of random graphs for use within test cases
// the exercise the autopilot package.
func (d *databaseChannelGraph) addRandChannel(node1, node2 *btcec.PublicKey,
capacity btcutil.Amount) (*ChannelEdge, *ChannelEdge, error) {
fetchNode := func(pub *btcec.PublicKey) (*channeldb.LightningNode, error) {
if pub != nil {
vertex, err := route.NewVertexFromBytes(
pub.SerializeCompressed(),
)
if err != nil {
return nil, err
}
dbNode, err := d.db.FetchLightningNode(vertex)
switch {
case err == channeldb.ErrGraphNodeNotFound:
fallthrough
case err == channeldb.ErrGraphNotFound:
graphNode := &channeldb.LightningNode{
HaveNodeAnnouncement: true,
Addresses: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
Features: lnwire.NewFeatureVector(
nil, lnwire.Features,
),
AuthSigBytes: testSig.Serialize(),
}
graphNode.AddPubKey(pub)
if err := d.db.AddLightningNode(graphNode); err != nil {
return nil, err
}
case err != nil:
return nil, err
}
return dbNode, nil
}
nodeKey, err := randKey()
if err != nil {
return nil, err
}
dbNode := &channeldb.LightningNode{
HaveNodeAnnouncement: true,
Addresses: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
Features: lnwire.NewFeatureVector(
nil, lnwire.Features,
),
AuthSigBytes: testSig.Serialize(),
}
dbNode.AddPubKey(nodeKey)
if err := d.db.AddLightningNode(dbNode); err != nil {
return nil, err
}
return dbNode, nil
}
vertex1, err := fetchNode(node1)
if err != nil {
return nil, nil, err
}
vertex2, err := fetchNode(node2)
if err != nil {
return nil, nil, err
}
var lnNode1, lnNode2 *btcec.PublicKey
if bytes.Compare(vertex1.PubKeyBytes[:], vertex2.PubKeyBytes[:]) == -1 {
lnNode1, _ = vertex1.PubKey()
lnNode2, _ = vertex2.PubKey()
} else {
lnNode1, _ = vertex2.PubKey()
lnNode2, _ = vertex1.PubKey()
}
chanID := randChanID()
edge := &channeldb.ChannelEdgeInfo{
ChannelID: chanID.ToUint64(),
Capacity: capacity,
}
edge.AddNodeKeys(lnNode1, lnNode2, lnNode1, lnNode2)
if err := d.db.AddChannelEdge(edge); err != nil {
return nil, nil, err
}
edgePolicy := &channeldb.ChannelEdgePolicy{
SigBytes: testSig.Serialize(),
ChannelID: chanID.ToUint64(),
LastUpdate: time.Now(),
TimeLockDelta: 10,
MinHTLC: 1,
MaxHTLC: lnwire.NewMSatFromSatoshis(capacity),
FeeBaseMSat: 10,
FeeProportionalMillionths: 10000,
MessageFlags: 1,
ChannelFlags: 0,
}
if err := d.db.UpdateEdgePolicy(edgePolicy); err != nil {
return nil, nil, err
}
edgePolicy = &channeldb.ChannelEdgePolicy{
SigBytes: testSig.Serialize(),
ChannelID: chanID.ToUint64(),
LastUpdate: time.Now(),
TimeLockDelta: 10,
MinHTLC: 1,
MaxHTLC: lnwire.NewMSatFromSatoshis(capacity),
FeeBaseMSat: 10,
FeeProportionalMillionths: 10000,
MessageFlags: 1,
ChannelFlags: 1,
}
if err := d.db.UpdateEdgePolicy(edgePolicy); err != nil {
return nil, nil, err
}
return &ChannelEdge{
ChanID: chanID,
Capacity: capacity,
Peer: dbNode{
db: d.db,
node: vertex1,
},
},
&ChannelEdge{
ChanID: chanID,
Capacity: capacity,
Peer: dbNode{
db: d.db,
node: vertex2,
},
},
nil
}
func (d *databaseChannelGraph) addRandNode() (*btcec.PublicKey, error) {
nodeKey, err := randKey()
if err != nil {
return nil, err
}
dbNode := &channeldb.LightningNode{
HaveNodeAnnouncement: true,
Addresses: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
Features: lnwire.NewFeatureVector(
nil, lnwire.Features,
),
AuthSigBytes: testSig.Serialize(),
}
dbNode.AddPubKey(nodeKey)
if err := d.db.AddLightningNode(dbNode); err != nil {
return nil, err
}
return nodeKey, nil
}
// memChannelGraph is an implementation of the autopilot.ChannelGraph backed by
// an in-memory graph.
type memChannelGraph struct {
graph map[NodeID]*memNode
}
// A compile time assertion to ensure memChannelGraph meets the
// autopilot.ChannelGraph interface.
var _ ChannelGraph = (*memChannelGraph)(nil)
// newMemChannelGraph creates a new blank in-memory channel graph
// implementation.
func newMemChannelGraph() *memChannelGraph {
return &memChannelGraph{
graph: make(map[NodeID]*memNode),
}
}
// ForEachNode is a higher-order function that should be called once for each
// connected node within the channel graph. If the passed callback returns an
// error, then execution should be terminated.
//
// NOTE: Part of the autopilot.ChannelGraph interface.
func (m memChannelGraph) ForEachNode(cb func(Node) error) error {
for _, node := range m.graph {
if err := cb(node); err != nil {
return err
}
}
return nil
}
// randChanID generates a new random channel ID.
func randChanID() lnwire.ShortChannelID {
id := atomic.AddUint64(&chanIDCounter, 1)
return lnwire.NewShortChanIDFromInt(id)
}
// randKey returns a random public key.
func randKey() (*btcec.PublicKey, error) {
priv, err := btcec.NewPrivateKey()
if err != nil {
return nil, err
}
return priv.PubKey(), nil
}
// addRandChannel creates a new channel two target nodes. This function is
// meant to aide in the generation of random graphs for use within test cases
// the exercise the autopilot package.
func (m *memChannelGraph) addRandChannel(node1, node2 *btcec.PublicKey,
capacity btcutil.Amount) (*ChannelEdge, *ChannelEdge, error) {
var (
vertex1, vertex2 *memNode
ok bool
)
if node1 != nil {
vertex1, ok = m.graph[NewNodeID(node1)]
if !ok {
vertex1 = &memNode{
pub: node1,
addrs: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
}
}
} else {
newPub, err := randKey()
if err != nil {
return nil, nil, err
}
vertex1 = &memNode{
pub: newPub,
addrs: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
}
}
if node2 != nil {
vertex2, ok = m.graph[NewNodeID(node2)]
if !ok {
vertex2 = &memNode{
pub: node2,
addrs: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
}
}
} else {
newPub, err := randKey()
if err != nil {
return nil, nil, err
}
vertex2 = &memNode{
pub: newPub,
addrs: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
}
}
edge1 := ChannelEdge{
ChanID: randChanID(),
Capacity: capacity,
Peer: vertex2,
}
vertex1.chans = append(vertex1.chans, edge1)
edge2 := ChannelEdge{
ChanID: randChanID(),
Capacity: capacity,
Peer: vertex1,
}
vertex2.chans = append(vertex2.chans, edge2)
m.graph[NewNodeID(vertex1.pub)] = vertex1
m.graph[NewNodeID(vertex2.pub)] = vertex2
return &edge1, &edge2, nil
}
func (m *memChannelGraph) addRandNode() (*btcec.PublicKey, error) {
newPub, err := randKey()
if err != nil {
return nil, err
}
vertex := &memNode{
pub: newPub,
addrs: []net.Addr{
&net.TCPAddr{
IP: bytes.Repeat([]byte("a"), 16),
},
},
}
m.graph[NewNodeID(newPub)] = vertex
return newPub, nil
}
// databaseChannelGraphCached wraps a channeldb.ChannelGraph instance with the
// necessary API to properly implement the autopilot.ChannelGraph interface.
type databaseChannelGraphCached struct {
db *channeldb.ChannelGraph
}
// A compile time assertion to ensure databaseChannelGraphCached meets the
// autopilot.ChannelGraph interface.
var _ ChannelGraph = (*databaseChannelGraphCached)(nil)
// ChannelGraphFromCachedDatabase returns an instance of the
// autopilot.ChannelGraph backed by a live, open channeldb instance.
func ChannelGraphFromCachedDatabase(db *channeldb.ChannelGraph) ChannelGraph {
return &databaseChannelGraphCached{
db: db,
}
}
// dbNodeCached is a wrapper struct around a database transaction for a
// channeldb.LightningNode. The wrapper methods implement the autopilot.Node
// interface.
type dbNodeCached struct {
node route.Vertex
channels map[uint64]*channeldb.DirectedChannel
}
// A compile time assertion to ensure dbNodeCached meets the autopilot.Node
// interface.
var _ Node = (*dbNodeCached)(nil)
// PubKey is the identity public key of the node.
//
// NOTE: Part of the autopilot.Node interface.
func (nc dbNodeCached) PubKey() [33]byte {
return nc.node
}
// Addrs returns a slice of publicly reachable public TCP addresses that the
// peer is known to be listening on.
//
// NOTE: Part of the autopilot.Node interface.
func (nc dbNodeCached) Addrs() []net.Addr {
// TODO: Add addresses to be usable by autopilot.
return []net.Addr{}
}
// ForEachChannel is a higher-order function that will be used to iterate
// through all edges emanating from/to the target node. For each active
// channel, this function should be called with the populated ChannelEdge that
// describes the active channel.
//
// NOTE: Part of the autopilot.Node interface.
func (nc dbNodeCached) ForEachChannel(cb func(ChannelEdge) error) error {
for cid, channel := range nc.channels {
edge := ChannelEdge{
ChanID: lnwire.NewShortChanIDFromInt(cid),
Capacity: channel.Capacity,
Peer: dbNodeCached{
node: channel.OtherNode,
},
}
if err := cb(edge); err != nil {
return err
}
}
return nil
}
// ForEachNode is a higher-order function that should be called once for each
// connected node within the channel graph. If the passed callback returns an
// error, then execution should be terminated.
//
// NOTE: Part of the autopilot.ChannelGraph interface.
func (dc *databaseChannelGraphCached) ForEachNode(cb func(Node) error) error {
return dc.db.ForEachNodeCached(func(n route.Vertex,
channels map[uint64]*channeldb.DirectedChannel) error {
if len(channels) > 0 {
node := dbNodeCached{
node: n,
channels: channels,
}
return cb(node)
}
return nil
})
}
// memNode is a purely in-memory implementation of the autopilot.Node
// interface.
type memNode struct {
pub *btcec.PublicKey
chans []ChannelEdge
addrs []net.Addr
}
// A compile time assertion to ensure memNode meets the autopilot.Node
// interface.
var _ Node = (*memNode)(nil)
// PubKey is the identity public key of the node. This will be used to attempt
// to target a node for channel opening by the main autopilot agent.
//
// NOTE: Part of the autopilot.Node interface.
func (m memNode) PubKey() [33]byte {
var n [33]byte
copy(n[:], m.pub.SerializeCompressed())
return n
}
// Addrs returns a slice of publicly reachable public TCP addresses that the
// peer is known to be listening on.
//
// NOTE: Part of the autopilot.Node interface.
func (m memNode) Addrs() []net.Addr {
return m.addrs
}
// ForEachChannel is a higher-order function that will be used to iterate
// through all edges emanating from/to the target node. For each active
// channel, this function should be called with the populated ChannelEdge that
// describes the active channel.
//
// NOTE: Part of the autopilot.Node interface.
func (m memNode) ForEachChannel(cb func(ChannelEdge) error) error {
for _, channel := range m.chans {
if err := cb(channel); err != nil {
return err
}
}
return nil
}
// Median returns the median value in the slice of Amounts.
func Median(vals []btcutil.Amount) btcutil.Amount {
sort.Slice(vals, func(i, j int) bool {
return vals[i] < vals[j]
})
num := len(vals)
switch {
case num == 0:
return 0
case num%2 == 0:
return (vals[num/2-1] + vals[num/2]) / 2
default:
return vals[num/2]
}
}