lnd.xprv/peer/test_utils.go

package peer

import (
	"bytes"
	crand "crypto/rand"
	"encoding/binary"
	"io"
	"io/ioutil"
	"math/rand"
	"net"
	"os"
	"testing"
	"time"

	"github.com/btcsuite/btcd/btcec"
	"github.com/btcsuite/btcd/chaincfg/chainhash"
	"github.com/btcsuite/btcd/wire"
	"github.com/btcsuite/btcutil"
	"github.com/lightningnetwork/lnd/chainntnfs"
	"github.com/lightningnetwork/lnd/channeldb"
	"github.com/lightningnetwork/lnd/htlcswitch"
	"github.com/lightningnetwork/lnd/input"
	"github.com/lightningnetwork/lnd/keychain"
	"github.com/lightningnetwork/lnd/lntest/mock"
	"github.com/lightningnetwork/lnd/lnwallet"
	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
	"github.com/lightningnetwork/lnd/lnwire"
	"github.com/lightningnetwork/lnd/netann"
	"github.com/lightningnetwork/lnd/queue"
	"github.com/lightningnetwork/lnd/shachain"
	"github.com/lightningnetwork/lnd/ticker"
	"github.com/stretchr/testify/require"
)

const (
	broadcastHeight = 100

	// timeout is a timeout value to use for tests which need to wait for
	// a return value on a channel.
	timeout = time.Second * 5
)

var (
	alicesPrivKey = []byte{
		0x2b, 0xd8, 0x06, 0xc9, 0x7f, 0x0e, 0x00, 0xaf,
		0x1a, 0x1f, 0xc3, 0x32, 0x8f, 0xa7, 0x63, 0xa9,
		0x26, 0x97, 0x23, 0xc8, 0xdb, 0x8f, 0xac, 0x4f,
		0x93, 0xaf, 0x71, 0xdb, 0x18, 0x6d, 0x6e, 0x90,
	}

	bobsPrivKey = []byte{
		0x81, 0xb6, 0x37, 0xd8, 0xfc, 0xd2, 0xc6, 0xda,
		0x63, 0x59, 0xe6, 0x96, 0x31, 0x13, 0xa1, 0x17,
		0xd, 0xe7, 0x95, 0xe4, 0xb7, 0x25, 0xb8, 0x4d,
		0x1e, 0xb, 0x4c, 0xfd, 0x9e, 0xc5, 0x8c, 0xe9,
	}

	// Use a hard-coded HD seed.
	testHdSeed = [32]byte{
		0xb7, 0x94, 0x38, 0x5f, 0x2d, 0x1e, 0xf7, 0xab,
		0x4d, 0x92, 0x73, 0xd1, 0x90, 0x63, 0x81, 0xb4,
		0x4f, 0x2f, 0x6f, 0x25, 0x88, 0xa3, 0xef, 0xb9,
		0x6a, 0x49, 0x18, 0x83, 0x31, 0x98, 0x47, 0x53,
	}

	// Just use some arbitrary bytes as delivery script.
	dummyDeliveryScript = alicesPrivKey

	// testTx is used as the default funding txn for single-funder channels.
	testTx = &wire.MsgTx{
		Version: 1,
		TxIn: []*wire.TxIn{
			{
				PreviousOutPoint: wire.OutPoint{
					Hash:  chainhash.Hash{},
					Index: 0xffffffff,
				},
				SignatureScript: []byte{0x04, 0x31, 0xdc, 0x00, 0x1b, 0x01, 0x62},
				Sequence:        0xffffffff,
			},
		},
		TxOut: []*wire.TxOut{
			{
				Value: 5000000000,
				PkScript: []byte{
					0x41, // OP_DATA_65
					0x04, 0xd6, 0x4b, 0xdf, 0xd0, 0x9e, 0xb1, 0xc5,
					0xfe, 0x29, 0x5a, 0xbd, 0xeb, 0x1d, 0xca, 0x42,
					0x81, 0xbe, 0x98, 0x8e, 0x2d, 0xa0, 0xb6, 0xc1,
					0xc6, 0xa5, 0x9d, 0xc2, 0x26, 0xc2, 0x86, 0x24,
					0xe1, 0x81, 0x75, 0xe8, 0x51, 0xc9, 0x6b, 0x97,
					0x3d, 0x81, 0xb0, 0x1c, 0xc3, 0x1f, 0x04, 0x78,
					0x34, 0xbc, 0x06, 0xd6, 0xd6, 0xed, 0xf6, 0x20,
					0xd1, 0x84, 0x24, 0x1a, 0x6a, 0xed, 0x8b, 0x63,
					0xa6, // 65-byte signature
					0xac, // OP_CHECKSIG
				},
			},
		},
		LockTime: 5,
	}
)

// noUpdate is a function which can be used as a parameter in createTestPeer to
// call the setup code with no custom values on the channels set up.
var noUpdate = func(a, b *channeldb.OpenChannel) {}

// createTestPeer creates a channel between two nodes, and returns a peer for
// one of the nodes, together with the channel seen from both nodes. It takes
// an updateChan function which can be used to modify the default values on
// the channel states for each peer.
func createTestPeer(notifier chainntnfs.ChainNotifier,
	publTx chan *wire.MsgTx, updateChan func(a, b *channeldb.OpenChannel)) (
	*Brontide, *lnwallet.LightningChannel, func(), error) {

	aliceKeyPriv, aliceKeyPub := btcec.PrivKeyFromBytes(
		btcec.S256(), alicesPrivKey,
	)
	aliceKeySigner := &keychain.PrivKeyDigestSigner{PrivKey: aliceKeyPriv}
	bobKeyPriv, bobKeyPub := btcec.PrivKeyFromBytes(
		btcec.S256(), bobsPrivKey,
	)

	channelCapacity := btcutil.Amount(10 * 1e8)
	channelBal := channelCapacity / 2
	aliceDustLimit := btcutil.Amount(200)
	bobDustLimit := btcutil.Amount(1300)
	csvTimeoutAlice := uint32(5)
	csvTimeoutBob := uint32(4)

	prevOut := &wire.OutPoint{
		Hash:  chainhash.Hash(testHdSeed),
		Index: 0,
	}
	fundingTxIn := wire.NewTxIn(prevOut, nil, nil)

	aliceCfg := channeldb.ChannelConfig{
		ChannelConstraints: channeldb.ChannelConstraints{
			DustLimit:        aliceDustLimit,
			MaxPendingAmount: lnwire.MilliSatoshi(rand.Int63()),
			ChanReserve:      btcutil.Amount(rand.Int63()),
			MinHTLC:          lnwire.MilliSatoshi(rand.Int63()),
			MaxAcceptedHtlcs: uint16(rand.Int31()),
			CsvDelay:         uint16(csvTimeoutAlice),
		},
		MultiSigKey: keychain.KeyDescriptor{
			PubKey: aliceKeyPub,
		},
		RevocationBasePoint: keychain.KeyDescriptor{
			PubKey: aliceKeyPub,
		},
		PaymentBasePoint: keychain.KeyDescriptor{
			PubKey: aliceKeyPub,
		},
		DelayBasePoint: keychain.KeyDescriptor{
			PubKey: aliceKeyPub,
		},
		HtlcBasePoint: keychain.KeyDescriptor{
			PubKey: aliceKeyPub,
		},
	}
	bobCfg := channeldb.ChannelConfig{
		ChannelConstraints: channeldb.ChannelConstraints{
			DustLimit:        bobDustLimit,
			MaxPendingAmount: lnwire.MilliSatoshi(rand.Int63()),
			ChanReserve:      btcutil.Amount(rand.Int63()),
			MinHTLC:          lnwire.MilliSatoshi(rand.Int63()),
			MaxAcceptedHtlcs: uint16(rand.Int31()),
			CsvDelay:         uint16(csvTimeoutBob),
		},
		MultiSigKey: keychain.KeyDescriptor{
			PubKey: bobKeyPub,
		},
		RevocationBasePoint: keychain.KeyDescriptor{
			PubKey: bobKeyPub,
		},
		PaymentBasePoint: keychain.KeyDescriptor{
			PubKey: bobKeyPub,
		},
		DelayBasePoint: keychain.KeyDescriptor{
			PubKey: bobKeyPub,
		},
		HtlcBasePoint: keychain.KeyDescriptor{
			PubKey: bobKeyPub,
		},
	}

	bobRoot, err := chainhash.NewHash(bobKeyPriv.Serialize())
	if err != nil {
		return nil, nil, nil, err
	}
	bobPreimageProducer := shachain.NewRevocationProducer(*bobRoot)
	bobFirstRevoke, err := bobPreimageProducer.AtIndex(0)
	if err != nil {
		return nil, nil, nil, err
	}
	bobCommitPoint := input.ComputeCommitmentPoint(bobFirstRevoke[:])

	aliceRoot, err := chainhash.NewHash(aliceKeyPriv.Serialize())
	if err != nil {
		return nil, nil, nil, err
	}
	alicePreimageProducer := shachain.NewRevocationProducer(*aliceRoot)
	aliceFirstRevoke, err := alicePreimageProducer.AtIndex(0)
	if err != nil {
		return nil, nil, nil, err
	}
	aliceCommitPoint := input.ComputeCommitmentPoint(aliceFirstRevoke[:])

	aliceCommitTx, bobCommitTx, err := lnwallet.CreateCommitmentTxns(
		channelBal, channelBal, &aliceCfg, &bobCfg, aliceCommitPoint,
		bobCommitPoint, *fundingTxIn, channeldb.SingleFunderTweaklessBit,
	)
	if err != nil {
		return nil, nil, nil, err
	}

	alicePath, err := ioutil.TempDir("", "alicedb")
	if err != nil {
		return nil, nil, nil, err
	}

	dbAlice, err := channeldb.Open(alicePath)
	if err != nil {
		return nil, nil, nil, err
	}

	bobPath, err := ioutil.TempDir("", "bobdb")
	if err != nil {
		return nil, nil, nil, err
	}

	dbBob, err := channeldb.Open(bobPath)
	if err != nil {
		return nil, nil, nil, err
	}

	estimator := chainfee.NewStaticEstimator(12500, 0)
	feePerKw, err := estimator.EstimateFeePerKW(1)
	if err != nil {
		return nil, nil, nil, err
	}

	// TODO(roasbeef): need to factor in commit fee?
	aliceCommit := channeldb.ChannelCommitment{
		CommitHeight:  0,
		LocalBalance:  lnwire.NewMSatFromSatoshis(channelBal),
		RemoteBalance: lnwire.NewMSatFromSatoshis(channelBal),
		FeePerKw:      btcutil.Amount(feePerKw),
		CommitFee:     feePerKw.FeeForWeight(input.CommitWeight),
		CommitTx:      aliceCommitTx,
		CommitSig:     bytes.Repeat([]byte{1}, 71),
	}
	bobCommit := channeldb.ChannelCommitment{
		CommitHeight:  0,
		LocalBalance:  lnwire.NewMSatFromSatoshis(channelBal),
		RemoteBalance: lnwire.NewMSatFromSatoshis(channelBal),
		FeePerKw:      btcutil.Amount(feePerKw),
		CommitFee:     feePerKw.FeeForWeight(input.CommitWeight),
		CommitTx:      bobCommitTx,
		CommitSig:     bytes.Repeat([]byte{1}, 71),
	}

	var chanIDBytes [8]byte
	if _, err := io.ReadFull(crand.Reader, chanIDBytes[:]); err != nil {
		return nil, nil, nil, err
	}

	shortChanID := lnwire.NewShortChanIDFromInt(
		binary.BigEndian.Uint64(chanIDBytes[:]),
	)

	aliceChannelState := &channeldb.OpenChannel{
		LocalChanCfg:            aliceCfg,
		RemoteChanCfg:           bobCfg,
		IdentityPub:             aliceKeyPub,
		FundingOutpoint:         *prevOut,
		ShortChannelID:          shortChanID,
		ChanType:                channeldb.SingleFunderTweaklessBit,
		IsInitiator:             true,
		Capacity:                channelCapacity,
		RemoteCurrentRevocation: bobCommitPoint,
		RevocationProducer:      alicePreimageProducer,
		RevocationStore:         shachain.NewRevocationStore(),
		LocalCommitment:         aliceCommit,
		RemoteCommitment:        aliceCommit,
		Db:                      dbAlice,
		Packager:                channeldb.NewChannelPackager(shortChanID),
		FundingTxn:              testTx,
	}
	bobChannelState := &channeldb.OpenChannel{
		LocalChanCfg:            bobCfg,
		RemoteChanCfg:           aliceCfg,
		IdentityPub:             bobKeyPub,
		FundingOutpoint:         *prevOut,
		ChanType:                channeldb.SingleFunderTweaklessBit,
		IsInitiator:             false,
		Capacity:                channelCapacity,
		RemoteCurrentRevocation: aliceCommitPoint,
		RevocationProducer:      bobPreimageProducer,
		RevocationStore:         shachain.NewRevocationStore(),
		LocalCommitment:         bobCommit,
		RemoteCommitment:        bobCommit,
		Db:                      dbBob,
		Packager:                channeldb.NewChannelPackager(shortChanID),
	}

	// Set custom values on the channel states.
	updateChan(aliceChannelState, bobChannelState)

	aliceAddr := &net.TCPAddr{
		IP:   net.ParseIP("127.0.0.1"),
		Port: 18555,
	}

	if err := aliceChannelState.SyncPending(aliceAddr, 0); err != nil {
		return nil, nil, nil, err
	}

	bobAddr := &net.TCPAddr{
		IP:   net.ParseIP("127.0.0.1"),
		Port: 18556,
	}

	if err := bobChannelState.SyncPending(bobAddr, 0); err != nil {
		return nil, nil, nil, err
	}

	cleanUpFunc := func() {
		os.RemoveAll(bobPath)
		os.RemoveAll(alicePath)
	}

	aliceSigner := &mock.SingleSigner{Privkey: aliceKeyPriv}
	bobSigner := &mock.SingleSigner{Privkey: bobKeyPriv}

	alicePool := lnwallet.NewSigPool(1, aliceSigner)
	channelAlice, err := lnwallet.NewLightningChannel(
		aliceSigner, aliceChannelState, alicePool,
	)
	if err != nil {
		return nil, nil, nil, err
	}
	_ = alicePool.Start()

	bobPool := lnwallet.NewSigPool(1, bobSigner)
	channelBob, err := lnwallet.NewLightningChannel(
		bobSigner, bobChannelState, bobPool,
	)
	if err != nil {
		return nil, nil, nil, err
	}
	_ = bobPool.Start()

	chainIO := &mock.ChainIO{
		BestHeight: broadcastHeight,
	}
	wallet := &lnwallet.LightningWallet{
		WalletController: &mock.WalletController{
			RootKey:               aliceKeyPriv,
			PublishedTransactions: publTx,
		},
	}

	_, currentHeight, err := chainIO.GetBestBlock()
	if err != nil {
		return nil, nil, nil, err
	}

	htlcSwitch, err := htlcswitch.New(htlcswitch.Config{
		DB:             dbAlice,
		SwitchPackager: channeldb.NewSwitchPackager(),
		Notifier:       notifier,
		FwdEventTicker: ticker.New(
			htlcswitch.DefaultFwdEventInterval),
		LogEventTicker: ticker.New(
			htlcswitch.DefaultLogInterval),
		AckEventTicker: ticker.New(
			htlcswitch.DefaultAckInterval),
	}, uint32(currentHeight))
	if err != nil {
		return nil, nil, nil, err
	}
	if err = htlcSwitch.Start(); err != nil {
		return nil, nil, nil, err
	}

	nodeSignerAlice := netann.NewNodeSigner(aliceKeySigner)

	const chanActiveTimeout = time.Minute

	chanStatusMgr, err := netann.NewChanStatusManager(&netann.ChanStatusConfig{
		ChanStatusSampleInterval: 30 * time.Second,
		ChanEnableTimeout:        chanActiveTimeout,
		ChanDisableTimeout:       2 * time.Minute,
		DB:                       dbAlice,
		Graph:                    dbAlice.ChannelGraph(),
		MessageSigner:            nodeSignerAlice,
		OurPubKey:                aliceKeyPub,
		IsChannelActive:          htlcSwitch.HasActiveLink,
		ApplyChannelUpdate:       func(*lnwire.ChannelUpdate) error { return nil },
	})
	if err != nil {
		return nil, nil, nil, err
	}
	if err = chanStatusMgr.Start(); err != nil {
		return nil, nil, nil, err
	}

	errBuffer, err := queue.NewCircularBuffer(ErrorBufferSize)
	if err != nil {
		return nil, nil, nil, err
	}

	var pubKey [33]byte
	copy(pubKey[:], aliceKeyPub.SerializeCompressed())

	cfgAddr := &lnwire.NetAddress{
		IdentityKey: aliceKeyPub,
		Address:     aliceAddr,
		ChainNet:    wire.SimNet,
	}

	cfg := &Config{
		Addr:        cfgAddr,
		PubKeyBytes: pubKey,
		ErrorBuffer: errBuffer,
		ChainIO:     chainIO,
		Switch:      htlcSwitch,

		ChanActiveTimeout: chanActiveTimeout,
		InterceptSwitch:   htlcswitch.NewInterceptableSwitch(htlcSwitch),

		ChannelDB:      dbAlice,
		FeeEstimator:   estimator,
		Wallet:         wallet,
		ChainNotifier:  notifier,
		ChanStatusMgr:  chanStatusMgr,
		DisconnectPeer: func(b *btcec.PublicKey) error { return nil },
	}

	alicePeer := NewBrontide(*cfg)

	chanID := lnwire.NewChanIDFromOutPoint(channelAlice.ChannelPoint())
	alicePeer.activeChannels[chanID] = channelAlice

	alicePeer.wg.Add(1)
	go alicePeer.channelManager()

	return alicePeer, channelBob, cleanUpFunc, nil
}

type mockMessageConn struct {
	t *testing.T

	// MessageConn embeds our interface so that the mock does not need to
	// implement every function. The mock will panic if an unspecified function
	// is called.
	MessageConn

	// writtenMessages is a channel that our mock pushes written messages into.
	writtenMessages chan []byte
}

func newMockConn(t *testing.T, expectedMessages int) *mockMessageConn {
	return &mockMessageConn{
		t:               t,
		writtenMessages: make(chan []byte, expectedMessages),
	}
}

// SetWriteDeadline mocks setting write deadline for our conn.
func (m *mockMessageConn) SetWriteDeadline(time.Time) error {
	return nil
}

// Flush mocks a message conn flush.
func (m *mockMessageConn) Flush() (int, error) {
	return 0, nil
}

// WriteMessage mocks sending of a message on our connection. It will push
// the bytes sent into the mock's writtenMessages channel.
func (m *mockMessageConn) WriteMessage(msg []byte) error {
	select {
	case m.writtenMessages <- msg:
	case <-time.After(timeout):
		m.t.Fatalf("timeout sending message: %v", msg)
	}

	return nil
}

// assertWrite asserts that our mock as had WriteMessage called with the byte
// slice we expect.
func (m *mockMessageConn) assertWrite(expected []byte) {
	select {
	case actual := <-m.writtenMessages:
		require.Equal(m.t, expected, actual)

	case <-time.After(timeout):
		m.t.Fatalf("timeout waiting for write: %v", expected)
	}
}