lnd.xprv/autopilot/graph.go
2018-08-02 18:20:49 -07:00

425 lines
11 KiB
Go

package autopilot
import (
"bytes"
"math/big"
"net"
"sync/atomic"
"time"
"github.com/btcsuite/btcd/btcec"
"github.com/btcsuite/btcutil"
"github.com/coreos/bbolt"
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/lnwire"
)
var (
testSig = &btcec.Signature{
R: new(big.Int),
S: new(big.Int),
}
_, _ = testSig.R.SetString("63724406601629180062774974542967536251589935445068131219452686511677818569431", 10)
_, _ = testSig.S.SetString("18801056069249825825291287104931333862866033135609736119018462340006816851118", 10)
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 {
tx *bolt.Tx
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.
//
// NOTE: Part of the autopilot.Node interface.
func (d dbNode) PubKey() *btcec.PublicKey {
pubKey, _ := d.node.PubKey()
return pubKey
}
// 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.node.ForEachChannel(d.tx, func(tx *bolt.Tx,
ei *channeldb.ChannelEdgeInfo, ep, _ *channeldb.ChannelEdgePolicy) error {
pubkey, _ := ep.Node.PubKey()
edge := ChannelEdge{
Channel: Channel{
ChanID: lnwire.NewShortChanIDFromInt(ep.ChannelID),
Capacity: ei.Capacity,
FundedAmt: ei.Capacity,
Node: NewNodeID(pubkey),
},
Peer: dbNode{
tx: tx,
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(nil, func(tx *bolt.Tx, 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{
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 {
dbNode, err := d.db.FetchLightningNode(pub)
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.GlobalFeatures),
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.GlobalFeatures),
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,
FeeBaseMSat: 10,
FeeProportionalMillionths: 10000,
Flags: 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,
FeeBaseMSat: 10,
FeeProportionalMillionths: 10000,
Flags: 1,
}
if err := d.db.UpdateEdgePolicy(edgePolicy); err != nil {
return nil, nil, err
}
return &ChannelEdge{
Channel: Channel{
ChanID: chanID,
Capacity: capacity,
},
Peer: dbNode{
node: vertex1,
},
},
&ChannelEdge{
Channel: Channel{
ChanID: chanID,
Capacity: capacity,
},
Peer: dbNode{
node: vertex2,
},
},
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(btcec.S256())
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,
}
}
} else {
newPub, err := randKey()
if err != nil {
return nil, nil, err
}
vertex1 = memNode{
pub: newPub,
}
}
if node2 != nil {
vertex2, ok = m.graph[NewNodeID(node2)]
if !ok {
vertex2 = memNode{
pub: node2,
}
}
} else {
newPub, err := randKey()
if err != nil {
return nil, nil, err
}
vertex2 = memNode{
pub: newPub,
}
}
channel := Channel{
ChanID: randChanID(),
Capacity: capacity,
}
edge1 := ChannelEdge{
Channel: channel,
Peer: vertex2,
}
vertex1.chans = append(vertex1.chans, edge1)
edge2 := ChannelEdge{
Channel: channel,
Peer: vertex1,
}
vertex2.chans = append(vertex2.chans, edge2)
m.graph[NewNodeID(vertex1.pub)] = vertex1
m.graph[NewNodeID(vertex2.pub)] = vertex2
return &edge1, &edge2, 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() *btcec.PublicKey {
return m.pub
}
// 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
}