// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package magicsock import ( "bytes" "context" crand "crypto/rand" "crypto/tls" "encoding/binary" "errors" "fmt" "io" "math/rand" "net" "net/http" "net/http/httptest" "net/netip" "os" "runtime" "strconv" "strings" "sync" "testing" "time" "unsafe" "go4.org/mem" "golang.zx2c4.com/wireguard/device" "golang.zx2c4.com/wireguard/tun/tuntest" "tailscale.com/derp" "tailscale.com/derp/derphttp" "tailscale.com/disco" "tailscale.com/ipn/ipnstate" "tailscale.com/net/netaddr" "tailscale.com/net/stun/stuntest" "tailscale.com/net/tstun" "tailscale.com/tailcfg" "tailscale.com/tstest" "tailscale.com/tstest/natlab" "tailscale.com/types/key" "tailscale.com/types/logger" "tailscale.com/types/netmap" "tailscale.com/types/nettype" "tailscale.com/util/cibuild" "tailscale.com/util/racebuild" "tailscale.com/wgengine/filter" "tailscale.com/wgengine/wgcfg" "tailscale.com/wgengine/wgcfg/nmcfg" "tailscale.com/wgengine/wglog" ) func init() { os.Setenv("IN_TS_TEST", "1") // Some of these tests lose a disco pong before establishing a // direct connection, so instead of waiting 5 seconds in the // test, reduce the wait period. // (In particular, TestActiveDiscovery.) discoPingInterval = 100 * time.Millisecond pingTimeoutDuration = 100 * time.Millisecond } // WaitReady waits until the magicsock is entirely initialized and connected // to its home DERP server. This is normally not necessary, since magicsock // is intended to be entirely asynchronous, but it helps eliminate race // conditions in tests. In particular, you can't expect two test magicsocks // to be able to connect to each other through a test DERP unless they are // both fully initialized before you try. func (c *Conn) WaitReady(t testing.TB) { t.Helper() timer := time.NewTimer(10 * time.Second) defer timer.Stop() select { case <-c.derpStarted: return case <-c.connCtx.Done(): t.Fatalf("magicsock.Conn closed while waiting for readiness") case <-timer.C: t.Fatalf("timeout waiting for readiness") } } func runDERPAndStun(t *testing.T, logf logger.Logf, l nettype.PacketListener, stunIP netip.Addr) (derpMap *tailcfg.DERPMap, cleanup func()) { d := derp.NewServer(key.NewNode(), logf) httpsrv := httptest.NewUnstartedServer(derphttp.Handler(d)) httpsrv.Config.ErrorLog = logger.StdLogger(logf) httpsrv.Config.TLSNextProto = make(map[string]func(*http.Server, *tls.Conn, http.Handler)) httpsrv.StartTLS() stunAddr, stunCleanup := stuntest.ServeWithPacketListener(t, l) m := &tailcfg.DERPMap{ Regions: map[int]*tailcfg.DERPRegion{ 1: { RegionID: 1, RegionCode: "test", Nodes: []*tailcfg.DERPNode{ { Name: "t1", RegionID: 1, HostName: "test-node.unused", IPv4: "127.0.0.1", IPv6: "none", STUNPort: stunAddr.Port, DERPPort: httpsrv.Listener.Addr().(*net.TCPAddr).Port, InsecureForTests: true, STUNTestIP: stunIP.String(), }, }, }, }, } cleanup = func() { httpsrv.CloseClientConnections() httpsrv.Close() d.Close() stunCleanup() } return m, cleanup } // magicStack is a magicsock, plus all the stuff around it that's // necessary to send and receive packets to test e2e wireguard // happiness. type magicStack struct { privateKey key.NodePrivate epCh chan []tailcfg.Endpoint // endpoint updates produced by this peer conn *Conn // the magicsock itself tun *tuntest.ChannelTUN // TUN device to send/receive packets tsTun *tstun.Wrapper // wrapped tun that implements filtering and wgengine hooks dev *device.Device // the wireguard-go Device that connects the previous things wgLogger *wglog.Logger // wireguard-go log wrapper } // newMagicStack builds and initializes an idle magicsock and // friends. You need to call conn.SetNetworkMap and dev.Reconfig // before anything interesting happens. func newMagicStack(t testing.TB, logf logger.Logf, l nettype.PacketListener, derpMap *tailcfg.DERPMap) *magicStack { privateKey := key.NewNode() return newMagicStackWithKey(t, logf, l, derpMap, privateKey) } func newMagicStackWithKey(t testing.TB, logf logger.Logf, l nettype.PacketListener, derpMap *tailcfg.DERPMap, privateKey key.NodePrivate) *magicStack { t.Helper() epCh := make(chan []tailcfg.Endpoint, 100) // arbitrary conn, err := NewConn(Options{ Logf: logf, TestOnlyPacketListener: l, EndpointsFunc: func(eps []tailcfg.Endpoint) { epCh <- eps }, }) if err != nil { t.Fatalf("constructing magicsock: %v", err) } conn.SetDERPMap(derpMap) if err := conn.SetPrivateKey(privateKey); err != nil { t.Fatalf("setting private key in magicsock: %v", err) } tun := tuntest.NewChannelTUN() tsTun := tstun.Wrap(logf, tun.TUN()) tsTun.SetFilter(filter.NewAllowAllForTest(logf)) wgLogger := wglog.NewLogger(logf) dev := wgcfg.NewDevice(tsTun, conn.Bind(), wgLogger.DeviceLogger) dev.Up() // Wait for magicsock to connect up to DERP. conn.WaitReady(t) // Wait for first endpoint update to be available deadline := time.Now().Add(2 * time.Second) for len(epCh) == 0 && time.Now().Before(deadline) { time.Sleep(100 * time.Millisecond) } return &magicStack{ privateKey: privateKey, epCh: epCh, conn: conn, tun: tun, tsTun: tsTun, dev: dev, wgLogger: wgLogger, } } func (s *magicStack) Reconfig(cfg *wgcfg.Config) error { s.wgLogger.SetPeers(cfg.Peers) return wgcfg.ReconfigDevice(s.dev, cfg, s.conn.logf) } func (s *magicStack) String() string { pub := s.Public() return pub.ShortString() } func (s *magicStack) Close() { s.dev.Close() s.conn.Close() } func (s *magicStack) Public() key.NodePublic { return s.privateKey.Public() } func (s *magicStack) Status() *ipnstate.Status { var sb ipnstate.StatusBuilder s.conn.UpdateStatus(&sb) return sb.Status() } // IP returns the Tailscale IP address assigned to this magicStack. // // Something external needs to provide a NetworkMap and WireGuard // configs to the magicStack in order for it to acquire an IP // address. See meshStacks for one possible source of netmaps and IPs. func (s *magicStack) IP() netip.Addr { for deadline := time.Now().Add(5 * time.Second); time.Now().Before(deadline); time.Sleep(10 * time.Millisecond) { st := s.Status() if len(st.TailscaleIPs) > 0 { return st.TailscaleIPs[0] } } panic("timed out waiting for magicstack to get an IP assigned") } // meshStacks monitors epCh on all given ms, and plumbs network maps // and WireGuard configs into everyone to form a full mesh that has up // to date endpoint info. Think of it as an extremely stripped down // and purpose-built Tailscale control plane. func meshStacks(logf logger.Logf, mutateNetmap func(idx int, nm *netmap.NetworkMap), ms ...*magicStack) (cleanup func()) { ctx, cancel := context.WithCancel(context.Background()) // Serialize all reconfigurations globally, just to keep things // simpler. var ( mu sync.Mutex eps = make([][]tailcfg.Endpoint, len(ms)) ) buildNetmapLocked := func(myIdx int) *netmap.NetworkMap { me := ms[myIdx] nm := &netmap.NetworkMap{ PrivateKey: me.privateKey, NodeKey: me.privateKey.Public(), Addresses: []netip.Prefix{netip.PrefixFrom(netaddr.IPv4(1, 0, 0, byte(myIdx+1)), 32)}, } for i, peer := range ms { if i == myIdx { continue } addrs := []netip.Prefix{netip.PrefixFrom(netaddr.IPv4(1, 0, 0, byte(i+1)), 32)} peer := &tailcfg.Node{ ID: tailcfg.NodeID(i + 1), Name: fmt.Sprintf("node%d", i+1), Key: peer.privateKey.Public(), DiscoKey: peer.conn.DiscoPublicKey(), Addresses: addrs, AllowedIPs: addrs, Endpoints: epStrings(eps[i]), DERP: "127.3.3.40:1", } nm.Peers = append(nm.Peers, peer) } if mutateNetmap != nil { mutateNetmap(myIdx, nm) } return nm } updateEps := func(idx int, newEps []tailcfg.Endpoint) { mu.Lock() defer mu.Unlock() eps[idx] = newEps for i, m := range ms { nm := buildNetmapLocked(i) m.conn.SetNetworkMap(nm) peerSet := make(map[key.NodePublic]struct{}, len(nm.Peers)) for _, peer := range nm.Peers { peerSet[peer.Key] = struct{}{} } m.conn.UpdatePeers(peerSet) wg, err := nmcfg.WGCfg(nm, logf, netmap.AllowSingleHosts, "") if err != nil { // We're too far from the *testing.T to be graceful, // blow up. Shouldn't happen anyway. panic(fmt.Sprintf("failed to construct wgcfg from netmap: %v", err)) } if err := m.Reconfig(wg); err != nil { if ctx.Err() != nil || errors.Is(err, errConnClosed) { // shutdown race, don't care. return } panic(fmt.Sprintf("device reconfig failed: %v", err)) } } } var wg sync.WaitGroup wg.Add(len(ms)) for i := range ms { go func(myIdx int) { defer wg.Done() for { select { case <-ctx.Done(): return case eps := <-ms[myIdx].epCh: logf("conn%d endpoints update", myIdx+1) updateEps(myIdx, eps) } } }(i) } return func() { cancel() wg.Wait() } } func TestNewConn(t *testing.T) { tstest.PanicOnLog() tstest.ResourceCheck(t) epCh := make(chan string, 16) epFunc := func(endpoints []tailcfg.Endpoint) { for _, ep := range endpoints { epCh <- ep.Addr.String() } } stunAddr, stunCleanupFn := stuntest.Serve(t) defer stunCleanupFn() port := pickPort(t) conn, err := NewConn(Options{ Port: port, EndpointsFunc: epFunc, Logf: t.Logf, }) if err != nil { t.Fatal(err) } defer conn.Close() conn.SetDERPMap(stuntest.DERPMapOf(stunAddr.String())) conn.SetPrivateKey(key.NewNode()) go func() { var pkt [64 << 10]byte for { _, _, err := conn.receiveIPv4(pkt[:]) if err != nil { return } } }() timeout := time.After(10 * time.Second) var endpoints []string suffix := fmt.Sprintf(":%d", port) collectEndpoints: for { select { case ep := <-epCh: endpoints = append(endpoints, ep) if strings.HasSuffix(ep, suffix) { break collectEndpoints } case <-timeout: t.Fatalf("timeout with endpoints: %v", endpoints) } } } func pickPort(t testing.TB) uint16 { t.Helper() conn, err := net.ListenPacket("udp4", "127.0.0.1:0") if err != nil { t.Fatal(err) } defer conn.Close() return uint16(conn.LocalAddr().(*net.UDPAddr).Port) } func TestPickDERPFallback(t *testing.T) { tstest.PanicOnLog() tstest.ResourceCheck(t) c := newConn() dm := &tailcfg.DERPMap{ Regions: map[int]*tailcfg.DERPRegion{ 1: {}, 2: {}, 3: {}, 4: {}, 5: {}, 6: {}, 7: {}, 8: {}, }, } c.derpMap = dm a := c.pickDERPFallback() if a == 0 { t.Fatalf("pickDERPFallback returned 0") } // Test that it's consistent. for i := 0; i < 50; i++ { b := c.pickDERPFallback() if a != b { t.Fatalf("got inconsistent %d vs %d values", a, b) } } // Test that that the pointer value of c is blended in and // distribution over nodes works. got := map[int]int{} for i := 0; i < 50; i++ { c = newConn() c.derpMap = dm got[c.pickDERPFallback()]++ } t.Logf("distribution: %v", got) if len(got) < 2 { t.Errorf("expected more than 1 node; got %v", got) } // Test that stickiness works. const someNode = 123456 c.myDerp = someNode if got := c.pickDERPFallback(); got != someNode { t.Errorf("not sticky: got %v; want %v", got, someNode) } // TODO: test that disco-based clients changing to a new DERP // region causes this fallback to also move, once disco clients // have fixed DERP fallback logic. } // TestDeviceStartStop exercises the startup and shutdown logic of // wireguard-go, which is intimately intertwined with magicsock's own // lifecycle. We seem to be good at generating deadlocks here, so if // this test fails you should suspect a deadlock somewhere in startup // or shutdown. It may be an infrequent flake, so run with // -count=10000 to be sure. func TestDeviceStartStop(t *testing.T) { tstest.PanicOnLog() tstest.ResourceCheck(t) conn, err := NewConn(Options{ EndpointsFunc: func(eps []tailcfg.Endpoint) {}, Logf: t.Logf, }) if err != nil { t.Fatal(err) } defer conn.Close() tun := tuntest.NewChannelTUN() wgLogger := wglog.NewLogger(t.Logf) dev := wgcfg.NewDevice(tun.TUN(), conn.Bind(), wgLogger.DeviceLogger) dev.Up() dev.Close() } // Exercise a code path in sendDiscoMessage if the connection has been closed. func TestConnClosed(t *testing.T) { mstun := &natlab.Machine{Name: "stun"} m1 := &natlab.Machine{Name: "m1"} m2 := &natlab.Machine{Name: "m2"} inet := natlab.NewInternet() sif := mstun.Attach("eth0", inet) m1if := m1.Attach("eth0", inet) m2if := m2.Attach("eth0", inet) d := &devices{ m1: m1, m1IP: m1if.V4(), m2: m2, m2IP: m2if.V4(), stun: mstun, stunIP: sif.V4(), } logf, closeLogf := logger.LogfCloser(t.Logf) defer closeLogf() derpMap, cleanup := runDERPAndStun(t, logf, d.stun, d.stunIP) defer cleanup() ms1 := newMagicStack(t, logger.WithPrefix(logf, "conn1: "), d.m1, derpMap) defer ms1.Close() ms2 := newMagicStack(t, logger.WithPrefix(logf, "conn2: "), d.m2, derpMap) defer ms2.Close() cleanup = meshStacks(t.Logf, nil, ms1, ms2) defer cleanup() pkt := tuntest.Ping(ms2.IP(), ms1.IP()) if len(ms1.conn.activeDerp) == 0 { t.Errorf("unexpected DERP empty got: %v want: >0", len(ms1.conn.activeDerp)) } ms1.conn.Close() ms2.conn.Close() // This should hit a c.closed conditional in sendDiscoMessage() and return immediately. ms1.tun.Outbound <- pkt select { case <-ms2.tun.Inbound: t.Error("unexpected response with connection closed") case <-time.After(100 * time.Millisecond): } if len(ms1.conn.activeDerp) > 0 { t.Errorf("unexpected DERP active got: %v want:0", len(ms1.conn.activeDerp)) } } func makeNestable(t *testing.T) (logf logger.Logf, setT func(t *testing.T)) { var mu sync.RWMutex cur := t setT = func(t *testing.T) { mu.Lock() cur = t mu.Unlock() } logf = func(s string, args ...any) { mu.RLock() t := cur t.Helper() t.Logf(s, args...) mu.RUnlock() } return logf, setT } // localhostOnlyListener is a nettype.PacketListener that listens on // localhost (127.0.0.1 or ::1, depending on the requested network) // when asked to listen on the unspecified address. // // It's used in tests where we set up localhost-to-localhost // communication, because if you listen on the unspecified address on // macOS and Windows, you get an interactive firewall consent prompt // to allow the binding, which breaks our CIs. type localhostListener struct{} func (localhostListener) ListenPacket(ctx context.Context, network, address string) (net.PacketConn, error) { host, port, err := net.SplitHostPort(address) if err != nil { return nil, err } switch network { case "udp4": switch host { case "", "0.0.0.0": host = "127.0.0.1" case "127.0.0.1": default: return nil, fmt.Errorf("localhostListener cannot be asked to listen on %q", address) } case "udp6": switch host { case "", "::": host = "::1" case "::1": default: return nil, fmt.Errorf("localhostListener cannot be asked to listen on %q", address) } } var conf net.ListenConfig return conf.ListenPacket(ctx, network, net.JoinHostPort(host, port)) } func TestTwoDevicePing(t *testing.T) { l, ip := localhostListener{}, netaddr.IPv4(127, 0, 0, 1) n := &devices{ m1: l, m1IP: ip, m2: l, m2IP: ip, stun: l, stunIP: ip, } testTwoDevicePing(t, n) } // Legacy clients appear to new code as peers that know about DERP and // WireGuard, but don't have a disco key. Check that we can still // communicate successfully with such peers. func TestNoDiscoKey(t *testing.T) { tstest.PanicOnLog() tstest.ResourceCheck(t) derpMap, cleanup := runDERPAndStun(t, t.Logf, localhostListener{}, netaddr.IPv4(127, 0, 0, 1)) defer cleanup() m1 := newMagicStack(t, t.Logf, localhostListener{}, derpMap) defer m1.Close() m2 := newMagicStack(t, t.Logf, localhostListener{}, derpMap) defer m2.Close() removeDisco := func(idx int, nm *netmap.NetworkMap) { for _, p := range nm.Peers { p.DiscoKey = key.DiscoPublic{} } } cleanupMesh := meshStacks(t.Logf, removeDisco, m1, m2) defer cleanupMesh() // Wait for both peers to know about each other before we try to // ping. for { if s1 := m1.Status(); len(s1.Peer) != 1 { time.Sleep(10 * time.Millisecond) continue } if s2 := m2.Status(); len(s2.Peer) != 1 { time.Sleep(10 * time.Millisecond) continue } break } pkt := tuntest.Ping(m2.IP(), m1.IP()) m1.tun.Outbound <- pkt select { case <-m2.tun.Inbound: t.Logf("ping m1>m2 ok") case <-time.After(10 * time.Second): t.Fatalf("timed out waiting for ping to transit") } } func TestDiscokeyChange(t *testing.T) { tstest.PanicOnLog() tstest.ResourceCheck(t) derpMap, cleanup := runDERPAndStun(t, t.Logf, localhostListener{}, netaddr.IPv4(127, 0, 0, 1)) defer cleanup() m1Key := key.NewNode() m1 := newMagicStackWithKey(t, t.Logf, localhostListener{}, derpMap, m1Key) defer m1.Close() m2 := newMagicStack(t, t.Logf, localhostListener{}, derpMap) defer m2.Close() var ( mu sync.Mutex // Start with some random discoKey that isn't actually m1's key, // to simulate m2 coming up with knowledge of an old, expired // discokey. We'll switch to the correct one later in the test. m1DiscoKey = key.NewDisco().Public() ) setm1Key := func(idx int, nm *netmap.NetworkMap) { if idx != 1 { // only mutate m2's netmap return } if len(nm.Peers) != 1 { // m1 not in netmap yet. return } mu.Lock() defer mu.Unlock() nm.Peers[0].DiscoKey = m1DiscoKey } cleanupMesh := meshStacks(t.Logf, setm1Key, m1, m2) defer cleanupMesh() // Wait for both peers to know about each other. for { if s1 := m1.Status(); len(s1.Peer) != 1 { time.Sleep(10 * time.Millisecond) continue } if s2 := m2.Status(); len(s2.Peer) != 1 { time.Sleep(10 * time.Millisecond) continue } break } mu.Lock() m1DiscoKey = m1.conn.DiscoPublicKey() mu.Unlock() // Manually trigger an endpoint update to meshStacks, so it hands // m2 a new netmap. m1.conn.mu.Lock() m1.epCh <- m1.conn.lastEndpoints m1.conn.mu.Unlock() cleanup = newPinger(t, t.Logf, m1, m2) defer cleanup() mustDirect(t, t.Logf, m1, m2) mustDirect(t, t.Logf, m2, m1) } func TestActiveDiscovery(t *testing.T) { t.Run("simple_internet", func(t *testing.T) { t.Parallel() mstun := &natlab.Machine{Name: "stun"} m1 := &natlab.Machine{Name: "m1"} m2 := &natlab.Machine{Name: "m2"} inet := natlab.NewInternet() sif := mstun.Attach("eth0", inet) m1if := m1.Attach("eth0", inet) m2if := m2.Attach("eth0", inet) n := &devices{ m1: m1, m1IP: m1if.V4(), m2: m2, m2IP: m2if.V4(), stun: mstun, stunIP: sif.V4(), } testActiveDiscovery(t, n) }) t.Run("facing_easy_firewalls", func(t *testing.T) { mstun := &natlab.Machine{Name: "stun"} m1 := &natlab.Machine{ Name: "m1", PacketHandler: &natlab.Firewall{}, } m2 := &natlab.Machine{ Name: "m2", PacketHandler: &natlab.Firewall{}, } inet := natlab.NewInternet() sif := mstun.Attach("eth0", inet) m1if := m1.Attach("eth0", inet) m2if := m2.Attach("eth0", inet) n := &devices{ m1: m1, m1IP: m1if.V4(), m2: m2, m2IP: m2if.V4(), stun: mstun, stunIP: sif.V4(), } testActiveDiscovery(t, n) }) t.Run("facing_nats", func(t *testing.T) { mstun := &natlab.Machine{Name: "stun"} m1 := &natlab.Machine{ Name: "m1", PacketHandler: &natlab.Firewall{}, } nat1 := &natlab.Machine{ Name: "nat1", } m2 := &natlab.Machine{ Name: "m2", PacketHandler: &natlab.Firewall{}, } nat2 := &natlab.Machine{ Name: "nat2", } inet := natlab.NewInternet() lan1 := &natlab.Network{ Name: "lan1", Prefix4: netip.MustParsePrefix("192.168.0.0/24"), } lan2 := &natlab.Network{ Name: "lan2", Prefix4: netip.MustParsePrefix("192.168.1.0/24"), } sif := mstun.Attach("eth0", inet) nat1WAN := nat1.Attach("wan", inet) nat1LAN := nat1.Attach("lan1", lan1) nat2WAN := nat2.Attach("wan", inet) nat2LAN := nat2.Attach("lan2", lan2) m1if := m1.Attach("eth0", lan1) m2if := m2.Attach("eth0", lan2) lan1.SetDefaultGateway(nat1LAN) lan2.SetDefaultGateway(nat2LAN) nat1.PacketHandler = &natlab.SNAT44{ Machine: nat1, ExternalInterface: nat1WAN, Firewall: &natlab.Firewall{ TrustedInterface: nat1LAN, }, } nat2.PacketHandler = &natlab.SNAT44{ Machine: nat2, ExternalInterface: nat2WAN, Firewall: &natlab.Firewall{ TrustedInterface: nat2LAN, }, } n := &devices{ m1: m1, m1IP: m1if.V4(), m2: m2, m2IP: m2if.V4(), stun: mstun, stunIP: sif.V4(), } testActiveDiscovery(t, n) }) } type devices struct { m1 nettype.PacketListener m1IP netip.Addr m2 nettype.PacketListener m2IP netip.Addr stun nettype.PacketListener stunIP netip.Addr } // newPinger starts continuously sending test packets from srcM to // dstM, until cleanup is invoked to stop it. Each ping has 1 second // to transit the network. It is a test failure to lose a ping. func newPinger(t *testing.T, logf logger.Logf, src, dst *magicStack) (cleanup func()) { ctx, cancel := context.WithCancel(context.Background()) done := make(chan struct{}) one := func() bool { // TODO(danderson): requiring exactly zero packet loss // will probably be too strict for some tests we'd like to // run (e.g. discovery switching to a new path on // failure). Figure out what kind of thing would be // acceptable to test instead of "every ping must // transit". pkt := tuntest.Ping(dst.IP(), src.IP()) select { case src.tun.Outbound <- pkt: case <-ctx.Done(): return false } select { case <-dst.tun.Inbound: return true case <-time.After(10 * time.Second): // Very generous timeout here because depending on // magicsock setup races, the first handshake might get // eaten by the receiving end (if wireguard-go hasn't been // configured quite yet), so we have to wait for at least // the first retransmit from wireguard before we declare // failure. t.Errorf("timed out waiting for ping to transit") return true case <-ctx.Done(): // Try a little bit longer to consume the packet we're // waiting for. This is to deal with shutdown races, where // natlab may still be delivering a packet to us from a // goroutine. select { case <-dst.tun.Inbound: case <-time.After(time.Second): } return false } } cleanup = func() { cancel() <-done } // Synchronously transit one ping to get things started. This is // nice because it means that newPinger returning means we've // worked through initial connectivity. if !one() { cleanup() return } go func() { logf("sending ping stream from %s (%s) to %s (%s)", src, src.IP(), dst, dst.IP()) defer close(done) for one() { } }() return cleanup } // testActiveDiscovery verifies that two magicStacks tied to the given // devices can establish a direct p2p connection with each other. See // TestActiveDiscovery for the various configurations of devices that // get exercised. func testActiveDiscovery(t *testing.T, d *devices) { tstest.PanicOnLog() tstest.ResourceCheck(t) tlogf, setT := makeNestable(t) setT(t) start := time.Now() wlogf := func(msg string, args ...any) { t.Helper() msg = fmt.Sprintf("%s: %s", time.Since(start).Truncate(time.Microsecond), msg) tlogf(msg, args...) } logf, closeLogf := logger.LogfCloser(wlogf) defer closeLogf() derpMap, cleanup := runDERPAndStun(t, logf, d.stun, d.stunIP) defer cleanup() m1 := newMagicStack(t, logger.WithPrefix(logf, "conn1: "), d.m1, derpMap) defer m1.Close() m2 := newMagicStack(t, logger.WithPrefix(logf, "conn2: "), d.m2, derpMap) defer m2.Close() cleanup = meshStacks(logf, nil, m1, m2) defer cleanup() m1IP := m1.IP() m2IP := m2.IP() logf("IPs: %s %s", m1IP, m2IP) cleanup = newPinger(t, logf, m1, m2) defer cleanup() // Everything is now up and running, active discovery should find // a direct path between our peers. Wait for it to switch away // from DERP. mustDirect(t, logf, m1, m2) mustDirect(t, logf, m2, m1) logf("starting cleanup") } func mustDirect(t *testing.T, logf logger.Logf, m1, m2 *magicStack) { lastLog := time.Now().Add(-time.Minute) // See https://github.com/tailscale/tailscale/issues/654 // and https://github.com/tailscale/tailscale/issues/3247 for discussions of this deadline. for deadline := time.Now().Add(30 * time.Second); time.Now().Before(deadline); time.Sleep(10 * time.Millisecond) { pst := m1.Status().Peer[m2.Public()] if pst.CurAddr != "" { logf("direct link %s->%s found with addr %s", m1, m2, pst.CurAddr) return } if now := time.Now(); now.Sub(lastLog) > time.Second { logf("no direct path %s->%s yet, addrs %v", m1, m2, pst.Addrs) lastLog = now } } t.Errorf("magicsock did not find a direct path from %s to %s", m1, m2) } func testTwoDevicePing(t *testing.T, d *devices) { tstest.PanicOnLog() tstest.ResourceCheck(t) // This gets reassigned inside every test, so that the connections // all log using the "current" t.Logf function. Sigh. nestedLogf, setT := makeNestable(t) logf, closeLogf := logger.LogfCloser(nestedLogf) defer closeLogf() derpMap, cleanup := runDERPAndStun(t, logf, d.stun, d.stunIP) defer cleanup() m1 := newMagicStack(t, logf, d.m1, derpMap) defer m1.Close() m2 := newMagicStack(t, logf, d.m2, derpMap) defer m2.Close() cleanupMesh := meshStacks(logf, nil, m1, m2) defer cleanupMesh() // Wait for magicsock to be told about peers from meshStacks. tstest.WaitFor(10*time.Second, func() error { if p := m1.Status().Peer[m2.Public()]; p == nil || !p.InMagicSock { return errors.New("m1 not ready") } if p := m2.Status().Peer[m1.Public()]; p == nil || !p.InMagicSock { return errors.New("m2 not ready") } return nil }) m1cfg := &wgcfg.Config{ Name: "peer1", PrivateKey: m1.privateKey, Addresses: []netip.Prefix{netip.MustParsePrefix("1.0.0.1/32")}, Peers: []wgcfg.Peer{ { PublicKey: m2.privateKey.Public(), DiscoKey: m2.conn.DiscoPublicKey(), AllowedIPs: []netip.Prefix{netip.MustParsePrefix("1.0.0.2/32")}, }, }, } m2cfg := &wgcfg.Config{ Name: "peer2", PrivateKey: m2.privateKey, Addresses: []netip.Prefix{netip.MustParsePrefix("1.0.0.2/32")}, Peers: []wgcfg.Peer{ { PublicKey: m1.privateKey.Public(), DiscoKey: m1.conn.DiscoPublicKey(), AllowedIPs: []netip.Prefix{netip.MustParsePrefix("1.0.0.1/32")}, }, }, } if err := m1.Reconfig(m1cfg); err != nil { t.Fatal(err) } if err := m2.Reconfig(m2cfg); err != nil { t.Fatal(err) } // In the normal case, pings succeed immediately. // However, in the case of a handshake race, we need to retry. // With very bad luck, we can need to retry multiple times. allowedRetries := 3 if cibuild.On() { // Allow extra retries on small/flaky/loaded CI machines. allowedRetries *= 2 } // Retries take 5s each. Add 1s for some processing time. pingTimeout := 5*time.Second*time.Duration(allowedRetries) + time.Second // sendWithTimeout sends msg using send, checking that it is received unchanged from in. // It resends once per second until the send succeeds, or pingTimeout time has elapsed. sendWithTimeout := func(msg []byte, in chan []byte, send func()) error { start := time.Now() for time.Since(start) < pingTimeout { send() select { case recv := <-in: if !bytes.Equal(msg, recv) { return errors.New("ping did not transit correctly") } return nil case <-time.After(time.Second): // try again } } return errors.New("ping timed out") } ping1 := func(t *testing.T) { msg2to1 := tuntest.Ping(netip.MustParseAddr("1.0.0.1"), netip.MustParseAddr("1.0.0.2")) send := func() { m2.tun.Outbound <- msg2to1 t.Log("ping1 sent") } in := m1.tun.Inbound if err := sendWithTimeout(msg2to1, in, send); err != nil { t.Error(err) } } ping2 := func(t *testing.T) { msg1to2 := tuntest.Ping(netip.MustParseAddr("1.0.0.2"), netip.MustParseAddr("1.0.0.1")) send := func() { m1.tun.Outbound <- msg1to2 t.Log("ping2 sent") } in := m2.tun.Inbound if err := sendWithTimeout(msg1to2, in, send); err != nil { t.Error(err) } } outerT := t t.Run("ping 1.0.0.1", func(t *testing.T) { setT(t) defer setT(outerT) ping1(t) }) t.Run("ping 1.0.0.2", func(t *testing.T) { setT(t) defer setT(outerT) ping2(t) }) t.Run("ping 1.0.0.2 via SendPacket", func(t *testing.T) { setT(t) defer setT(outerT) msg1to2 := tuntest.Ping(netip.MustParseAddr("1.0.0.2"), netip.MustParseAddr("1.0.0.1")) send := func() { if err := m1.tsTun.InjectOutbound(msg1to2); err != nil { t.Fatal(err) } t.Log("SendPacket sent") } in := m2.tun.Inbound if err := sendWithTimeout(msg1to2, in, send); err != nil { t.Error(err) } }) t.Run("no-op dev1 reconfig", func(t *testing.T) { setT(t) defer setT(outerT) if err := m1.Reconfig(m1cfg); err != nil { t.Fatal(err) } ping1(t) ping2(t) }) } func TestDiscoMessage(t *testing.T) { c := newConn() c.logf = t.Logf c.privateKey = key.NewNode() peer1Pub := c.DiscoPublicKey() peer1Priv := c.discoPrivate n := &tailcfg.Node{ Key: key.NewNode().Public(), DiscoKey: peer1Pub, } c.peerMap.upsertEndpoint(&endpoint{ publicKey: n.Key, discoKey: n.DiscoKey, }, key.DiscoPublic{}) const payload = "why hello" var nonce [24]byte crand.Read(nonce[:]) pkt := peer1Pub.AppendTo([]byte("TS💬")) box := peer1Priv.Shared(c.discoPrivate.Public()).Seal([]byte(payload)) pkt = append(pkt, box...) got := c.handleDiscoMessage(pkt, netip.AddrPort{}, key.NodePublic{}) if !got { t.Error("failed to open it") } } // tests that having a endpoint.String prevents wireguard-go's // log.Printf("%v") of its conn.Endpoint values from using reflect to // walk into read mutex while they're being used and then causing data // races. func TestDiscoStringLogRace(t *testing.T) { de := new(endpoint) var wg sync.WaitGroup wg.Add(2) go func() { defer wg.Done() fmt.Fprintf(io.Discard, "%v", de) }() go func() { defer wg.Done() de.mu.Lock() }() wg.Wait() } func Test32bitAlignment(t *testing.T) { // Need an associated conn with non-nil noteRecvActivity to // trigger interesting work on the atomics in endpoint. called := 0 de := endpoint{ c: &Conn{ noteRecvActivity: func(key.NodePublic) { called++ }, }, } if off := unsafe.Offsetof(de.lastRecv); off%8 != 0 { t.Fatalf("endpoint.lastRecv is not 8-byte aligned") } de.noteRecvActivity() // verify this doesn't panic on 32-bit if called != 1 { t.Fatal("expected call to noteRecvActivity") } de.noteRecvActivity() if called != 1 { t.Error("expected no second call to noteRecvActivity") } } // newTestConn returns a new Conn. func newTestConn(t testing.TB) *Conn { t.Helper() port := pickPort(t) conn, err := NewConn(Options{ Logf: t.Logf, Port: port, TestOnlyPacketListener: localhostListener{}, EndpointsFunc: func(eps []tailcfg.Endpoint) { t.Logf("endpoints: %q", eps) }, }) if err != nil { t.Fatal(err) } return conn } // addTestEndpoint sets conn's network map to a single peer expected // to receive packets from sendConn (or DERP), and returns that peer's // nodekey and discokey. func addTestEndpoint(tb testing.TB, conn *Conn, sendConn net.PacketConn) (key.NodePublic, key.DiscoPublic) { // Give conn just enough state that it'll recognize sendConn as a // valid peer and not fall through to the legacy magicsock // codepath. discoKey := key.DiscoPublicFromRaw32(mem.B([]byte{31: 1})) nodeKey := key.NodePublicFromRaw32(mem.B([]byte{0: 'N', 1: 'K', 31: 0})) conn.SetNetworkMap(&netmap.NetworkMap{ Peers: []*tailcfg.Node{ { Key: nodeKey, DiscoKey: discoKey, Endpoints: []string{sendConn.LocalAddr().String()}, }, }, }) conn.SetPrivateKey(key.NodePrivateFromRaw32(mem.B([]byte{0: 1, 31: 0}))) _, err := conn.ParseEndpoint(nodeKey.UntypedHexString()) if err != nil { tb.Fatal(err) } conn.addValidDiscoPathForTest(nodeKey, netip.MustParseAddrPort(sendConn.LocalAddr().String())) return nodeKey, discoKey } func setUpReceiveFrom(tb testing.TB) (roundTrip func()) { if b, ok := tb.(*testing.B); ok { b.ReportAllocs() } conn := newTestConn(tb) tb.Cleanup(func() { conn.Close() }) conn.logf = logger.Discard sendConn, err := net.ListenPacket("udp4", "127.0.0.1:0") if err != nil { tb.Fatal(err) } tb.Cleanup(func() { sendConn.Close() }) addTestEndpoint(tb, conn, sendConn) var dstAddr net.Addr = conn.pconn4.LocalAddr() sendBuf := make([]byte, 1<<10) for i := range sendBuf { sendBuf[i] = 'x' } buf := make([]byte, 2<<10) return func() { if _, err := sendConn.WriteTo(sendBuf, dstAddr); err != nil { tb.Fatalf("WriteTo: %v", err) } n, ep, err := conn.receiveIPv4(buf) if err != nil { tb.Fatal(err) } _ = n _ = ep } } // goMajorVersion reports the major Go version and whether it is a Tailscale fork. // If parsing fails, goMajorVersion returns 0, false. func goMajorVersion(s string) (version int, isTS bool) { if !strings.HasPrefix(s, "go1.") { return 0, false } mm := s[len("go1."):] var major, rest string for _, sep := range []string{".", "rc", "beta", "-"} { i := strings.Index(mm, sep) if i > 0 { major, rest = mm[:i], mm[i:] break } } if major == "" { major = mm } n, err := strconv.Atoi(major) if err != nil { return 0, false } return n, strings.Contains(rest, "ts") } func TestGoMajorVersion(t *testing.T) { tests := []struct { version string wantN int wantTS bool }{ {"go1.15.8", 15, false}, {"go1.16rc1", 16, false}, {"go1.16rc1", 16, false}, {"go1.15.5-ts3bd89195a3", 15, true}, {"go1.15", 15, false}, {"go1.18-ts0d07ed810a", 18, true}, } for _, tt := range tests { n, ts := goMajorVersion(tt.version) if tt.wantN != n || tt.wantTS != ts { t.Errorf("goMajorVersion(%s) = %v, %v, want %v, %v", tt.version, n, ts, tt.wantN, tt.wantTS) } } // Ensure that the current Go version is parseable. n, _ := goMajorVersion(runtime.Version()) if n == 0 { t.Fatalf("unable to parse %v", runtime.Version()) } } func TestReceiveFromAllocs(t *testing.T) { if racebuild.On { t.Skip("alloc tests are unreliable with -race") } // Go 1.16 and before: allow 3 allocs. // Go 1.17: allow 2 allocs. // Go 1.17, Tailscale fork: allow 1 alloc. // Go 1.18+: allow 0 allocs. // Go 2.0: allow -1 allocs (projected). major, ts := goMajorVersion(runtime.Version()) maxAllocs := 3 switch { case major == 17 && !ts: maxAllocs = 2 case major == 17 && ts: maxAllocs = 1 case major >= 18: maxAllocs = 0 } t.Logf("allowing %d allocs for Go version %q", maxAllocs, runtime.Version()) roundTrip := setUpReceiveFrom(t) err := tstest.MinAllocsPerRun(t, uint64(maxAllocs), roundTrip) if err != nil { t.Fatal(err) } } func BenchmarkReceiveFrom(b *testing.B) { roundTrip := setUpReceiveFrom(b) for i := 0; i < b.N; i++ { roundTrip() } } func BenchmarkReceiveFrom_Native(b *testing.B) { b.ReportAllocs() recvConn, err := net.ListenPacket("udp4", "127.0.0.1:0") if err != nil { b.Fatal(err) } defer recvConn.Close() recvConnUDP := recvConn.(*net.UDPConn) sendConn, err := net.ListenPacket("udp4", "127.0.0.1:0") if err != nil { b.Fatal(err) } defer sendConn.Close() var dstAddr net.Addr = recvConn.LocalAddr() sendBuf := make([]byte, 1<<10) for i := range sendBuf { sendBuf[i] = 'x' } buf := make([]byte, 2<<10) for i := 0; i < b.N; i++ { if _, err := sendConn.WriteTo(sendBuf, dstAddr); err != nil { b.Fatalf("WriteTo: %v", err) } if _, _, err := recvConnUDP.ReadFromUDP(buf); err != nil { b.Fatalf("ReadFromUDP: %v", err) } } } // Test that a netmap update where node changes its node key but // doesn't change its disco key doesn't result in a broken state. // // https://github.com/tailscale/tailscale/issues/1391 func TestSetNetworkMapChangingNodeKey(t *testing.T) { conn := newTestConn(t) t.Cleanup(func() { conn.Close() }) var buf tstest.MemLogger conn.logf = buf.Logf conn.SetPrivateKey(key.NodePrivateFromRaw32(mem.B([]byte{0: 1, 31: 0}))) discoKey := key.DiscoPublicFromRaw32(mem.B([]byte{31: 1})) nodeKey1 := key.NodePublicFromRaw32(mem.B([]byte{0: 'N', 1: 'K', 2: '1', 31: 0})) nodeKey2 := key.NodePublicFromRaw32(mem.B([]byte{0: 'N', 1: 'K', 2: '2', 31: 0})) conn.SetNetworkMap(&netmap.NetworkMap{ Peers: []*tailcfg.Node{ { Key: nodeKey1, DiscoKey: discoKey, Endpoints: []string{"192.168.1.2:345"}, }, }, }) _, err := conn.ParseEndpoint(nodeKey1.UntypedHexString()) if err != nil { t.Fatal(err) } for i := 0; i < 3; i++ { conn.SetNetworkMap(&netmap.NetworkMap{ Peers: []*tailcfg.Node{ { Key: nodeKey2, DiscoKey: discoKey, Endpoints: []string{"192.168.1.2:345"}, }, }, }) } de, ok := conn.peerMap.endpointForNodeKey(nodeKey2) if ok && de.publicKey != nodeKey2 { t.Fatalf("discoEndpoint public key = %q; want %q", de.publicKey, nodeKey2) } if de.discoKey != discoKey { t.Errorf("discoKey = %v; want %v", de.discoKey, discoKey) } if _, ok := conn.peerMap.endpointForNodeKey(nodeKey1); ok { t.Errorf("didn't expect to find node for key1") } log := buf.String() wantSub := map[string]int{ "magicsock: got updated network map; 1 peers": 2, } for sub, want := range wantSub { got := strings.Count(log, sub) if got != want { t.Errorf("in log, count of substring %q = %v; want %v", sub, got, want) } } if t.Failed() { t.Logf("log output: %s", log) } } func TestRebindStress(t *testing.T) { conn := newTestConn(t) var buf tstest.MemLogger conn.logf = buf.Logf closed := false t.Cleanup(func() { if !closed { conn.Close() } }) ctx, cancel := context.WithCancel(context.Background()) defer cancel() errc := make(chan error, 1) go func() { buf := make([]byte, 1500) for { _, _, err := conn.receiveIPv4(buf) if ctx.Err() != nil { errc <- nil return } if err != nil { errc <- err return } } }() var wg sync.WaitGroup wg.Add(2) go func() { defer wg.Done() for i := 0; i < 2000; i++ { conn.Rebind() } }() go func() { defer wg.Done() for i := 0; i < 2000; i++ { conn.Rebind() } }() wg.Wait() cancel() if err := conn.Close(); err != nil { t.Fatal(err) } closed = true err := <-errc if err != nil { t.Fatalf("Got ReceiveIPv4 error: %v (is closed = %v). Log:\n%s", err, errors.Is(err, net.ErrClosed), buf.String()) } } func TestEndpointSetsEqual(t *testing.T) { s := func(ports ...uint16) (ret []tailcfg.Endpoint) { for _, port := range ports { ret = append(ret, tailcfg.Endpoint{ Addr: netip.AddrPortFrom(netip.Addr{}, port), }) } return } tests := []struct { a, b []tailcfg.Endpoint want bool }{ { want: true, }, { a: s(1, 2, 3), b: s(1, 2, 3), want: true, }, { a: s(1, 2), b: s(2, 1), want: true, }, { a: s(1, 2), b: s(2, 1, 1), want: true, }, { a: s(1, 2, 2), b: s(2, 1), want: true, }, { a: s(1, 2, 2), b: s(2, 1, 1), want: true, }, { a: s(1, 2, 2, 3), b: s(2, 1, 1), want: false, }, { a: s(1, 2, 2), b: s(2, 1, 1, 3), want: false, }, } for _, tt := range tests { if got := endpointSetsEqual(tt.a, tt.b); got != tt.want { t.Errorf("%q vs %q = %v; want %v", tt.a, tt.b, got, tt.want) } } } func TestBetterAddr(t *testing.T) { const ms = time.Millisecond al := func(ipps string, d time.Duration) addrLatency { return addrLatency{netip.MustParseAddrPort(ipps), d} } zero := addrLatency{} tests := []struct { a, b addrLatency want bool }{ {a: zero, b: zero, want: false}, {a: al("10.0.0.2:123", 5*ms), b: zero, want: true}, {a: zero, b: al("10.0.0.2:123", 5*ms), want: false}, {a: al("10.0.0.2:123", 5*ms), b: al("1.2.3.4:555", 6*ms), want: true}, {a: al("10.0.0.2:123", 5*ms), b: al("10.0.0.2:123", 10*ms), want: false}, // same IPPort // Prefer IPv6 if roughly equivalent: { a: al("[2001::5]:123", 100*ms), b: al("1.2.3.4:555", 91*ms), want: true, }, { a: al("1.2.3.4:555", 91*ms), b: al("[2001::5]:123", 100*ms), want: false, }, // But not if IPv4 is much faster: { a: al("[2001::5]:123", 100*ms), b: al("1.2.3.4:555", 30*ms), want: false, }, { a: al("1.2.3.4:555", 30*ms), b: al("[2001::5]:123", 100*ms), want: true, }, } for _, tt := range tests { got := betterAddr(tt.a, tt.b) if got != tt.want { t.Errorf("betterAddr(%+v, %+v) = %v; want %v", tt.a, tt.b, got, tt.want) continue } gotBack := betterAddr(tt.b, tt.a) if got && gotBack { t.Errorf("betterAddr(%+v, %+v) and betterAddr(%+v, %+v) both unexpectedly true", tt.a, tt.b, tt.b, tt.a) } } } func epStrings(eps []tailcfg.Endpoint) (ret []string) { for _, ep := range eps { ret = append(ret, ep.Addr.String()) } return } func TestStressSetNetworkMap(t *testing.T) { t.Parallel() conn := newTestConn(t) t.Cleanup(func() { conn.Close() }) var buf tstest.MemLogger conn.logf = buf.Logf conn.SetPrivateKey(key.NewNode()) const npeers = 5 present := make([]bool, npeers) allPeers := make([]*tailcfg.Node, npeers) for i := range allPeers { present[i] = true allPeers[i] = &tailcfg.Node{ DiscoKey: randDiscoKey(), Key: randNodeKey(), Endpoints: []string{fmt.Sprintf("192.168.1.2:%d", i)}, } } // Get a PRNG seed. If not provided, generate a new one to get extra coverage. seed, err := strconv.ParseUint(os.Getenv("TS_STRESS_SET_NETWORK_MAP_SEED"), 10, 64) if err != nil { var buf [8]byte crand.Read(buf[:]) seed = binary.LittleEndian.Uint64(buf[:]) } t.Logf("TS_STRESS_SET_NETWORK_MAP_SEED=%d", seed) prng := rand.New(rand.NewSource(int64(seed))) const iters = 1000 // approx 0.5s on an m1 mac for i := 0; i < iters; i++ { for j := 0; j < npeers; j++ { // Randomize which peers are present. if prng.Int()&1 == 0 { present[j] = !present[j] } // Randomize some peer disco keys and node keys. if prng.Int()&1 == 0 { allPeers[j].DiscoKey = randDiscoKey() } if prng.Int()&1 == 0 { allPeers[j].Key = randNodeKey() } } // Clone existing peers into a new netmap. peers := make([]*tailcfg.Node, 0, len(allPeers)) for peerIdx, p := range allPeers { if present[peerIdx] { peers = append(peers, p.Clone()) } } // Set the netmap. conn.SetNetworkMap(&netmap.NetworkMap{ Peers: peers, }) // Check invariants. if err := conn.peerMap.validate(); err != nil { t.Error(err) } } } func randDiscoKey() (k key.DiscoPublic) { return key.NewDisco().Public() } func randNodeKey() (k key.NodePublic) { return key.NewNode().Public() } // validate checks m for internal consistency and reports the first error encountered. // It is used in tests only, so it doesn't need to be efficient. func (m *peerMap) validate() error { seenEps := make(map[*endpoint]bool) for pub, pi := range m.byNodeKey { if got := pi.ep.publicKey; got != pub { return fmt.Errorf("byNodeKey[%v].publicKey = %v", pub, got) } if _, ok := seenEps[pi.ep]; ok { return fmt.Errorf("duplicate endpoint present: %v", pi.ep.publicKey) } seenEps[pi.ep] = true for ipp, v := range pi.ipPorts { if !v { return fmt.Errorf("m.byIPPort[%v] is false, expected map to be set-like", ipp) } if got := m.byIPPort[ipp]; got != pi { return fmt.Errorf("m.byIPPort[%v] = %v, want %v", ipp, got, pi) } } } for ipp, pi := range m.byIPPort { if !pi.ipPorts[ipp] { return fmt.Errorf("ipPorts[%v] for %v is false", ipp, pi.ep.publicKey) } pi2 := m.byNodeKey[pi.ep.publicKey] if pi != pi2 { return fmt.Errorf("byNodeKey[%v]=%p doesn't match byIPPort[%v]=%p", pi, pi, pi.ep.publicKey, pi2) } } publicToDisco := make(map[key.NodePublic]key.DiscoPublic) for disco, nodes := range m.nodesOfDisco { for pub, v := range nodes { if !v { return fmt.Errorf("m.nodeOfDisco[%v][%v] is false, expected map to be set-like", disco, pub) } if _, ok := m.byNodeKey[pub]; !ok { return fmt.Errorf("nodesOfDisco refers to public key %v, which is not present in byNodeKey", pub) } if _, ok := publicToDisco[pub]; ok { return fmt.Errorf("publicKey %v refers to multiple disco keys", pub) } publicToDisco[pub] = disco } } return nil } func TestBlockForeverConnUnblocks(t *testing.T) { c := newBlockForeverConn() done := make(chan error, 1) go func() { defer close(done) _, _, err := c.ReadFrom(make([]byte, 1)) done <- err }() time.Sleep(50 * time.Millisecond) // give ReadFrom time to get blocked if err := c.Close(); err != nil { t.Fatal(err) } timer := time.NewTimer(5 * time.Second) defer timer.Stop() select { case err := <-done: if err != net.ErrClosed { t.Errorf("got %v; want net.ErrClosed", err) } case <-timer.C: t.Fatal("timeout") } } func TestDiscoMagicMatches(t *testing.T) { // Convert our disco magic number into a uint32 and uint16 to test // against. We panic on an incorrect length here rather than try to be // generic with our BPF instructions below. // // Note that BPF uses network byte order (big-endian) when loading data // from a packet, so that is what we use to generate our magic numbers. if len(disco.Magic) != 6 { t.Fatalf("expected disco.Magic to be of length 6") } if m1 := binary.BigEndian.Uint32([]byte(disco.Magic[:4])); m1 != discoMagic1 { t.Errorf("first 4 bytes of disco magic don't match, got %v want %v", discoMagic1, m1) } if m2 := binary.BigEndian.Uint16([]byte(disco.Magic[4:6])); m2 != discoMagic2 { t.Errorf("last 2 bytes of disco magic don't match, got %v want %v", discoMagic2, m2) } }