Drop dependency on github.com/cyberdelia/go-metrics-graphite

The go-metrics-graphite package has been unmaintained for 10+ years,
which is a packaging and supply-chain concern for downstream
distributors (see #1831). Nebula only used its Config struct and Once()
entrypoint, so inline just those (~65 lines) into a local graphite.go,
preserving the upstream BSD-2-Clause copyright notice, and remove the
dependency.

Fixes #1831

Co-Authored-By: Claude <svc-devxp-claude@slack-corp.com>

connection_manager.go

@@ -105,12 +105,11 @@ func (cm *connectionManager) getInactivityTimeout() time.Duration {
 }
 
 func (cm *connectionManager) In(h *HostInfo) {
-	h.markIn()
+	h.in.Store(true)
 }
 
-// Out records outbound traffic and reports whether the local network changed since this tunnel last sent.
-func (cm *connectionManager) Out(h *HostInfo) bool {
-	return h.markOut(cm.intf.rebindEpoch.Load())
+func (cm *connectionManager) Out(h *HostInfo) {
+	h.out.Store(true)
 }
 
 func (cm *connectionManager) RelayUsed(localIndex uint32) {
@@ -129,7 +128,8 @@ func (cm *connectionManager) RelayUsed(localIndex uint32) {
 // getAndResetTrafficCheck returns if there was any inbound or outbound traffic within the last tick and
 // resets the state for this local index
 func (cm *connectionManager) getAndResetTrafficCheck(h *HostInfo, now time.Time) (bool, bool) {
-	in, out := h.takeTraffic()
+	in := h.in.Swap(false)
+	out := h.out.Swap(false)
 	if in || out {
 		h.lastUsed = now
 	}
@@ -340,7 +340,7 @@ func (cm *connectionManager) makeTrafficDecision(localIndex uint32, now time.Tim
 				"tunnelCheck", m{"state": "alive", "method": "passive"},
 			)
 		}
-		hostinfo.setPendingDeletion(false)
+		hostinfo.pendingDeletion.Store(false)
 
 		if mainHostInfo {
 			decision = tryRehandshake
@@ -363,7 +363,7 @@ func (cm *connectionManager) makeTrafficDecision(localIndex uint32, now time.Tim
 		return decision, hostinfo, primary
 	}
 
-	if hostinfo.isPendingDeletion() {
+	if hostinfo.pendingDeletion.Load() {
 		// We have already sent a test packet and nothing was returned, this hostinfo is dead
 		hostinfo.logger(cm.l).Info("Tunnel status",
 			"tunnelCheck", m{"state": "dead", "method": "active"},
@@ -414,7 +414,7 @@ func (cm *connectionManager) makeTrafficDecision(localIndex uint32, now time.Tim
 		}
 	}
 
-	hostinfo.setPendingDeletion(true)
+	hostinfo.pendingDeletion.Store(true)
 	cm.trafficTimer.Add(hostinfo.localIndexId, cm.pendingDeletionInterval)
 	return decision, hostinfo, nil
 }

connection_manager_test.go

@@ -86,25 +86,25 @@ func Test_NewConnectionManagerTest(t *testing.T) {
 	// We saw traffic out to vpnIp
 	nc.Out(hostinfo)
 	nc.In(hostinfo)
-	assert.False(t, hostinfo.isPendingDeletion())
+	assert.False(t, hostinfo.pendingDeletion.Load())
 	assert.Contains(t, nc.hostMap.Hosts, hostinfo.vpnAddrs[0])
 	assert.Contains(t, nc.hostMap.Indexes, hostinfo.localIndexId)
-	assert.True(t, hostinfo.sentSinceCheck())
-	assert.True(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.True(t, hostinfo.out.Load())
+	assert.True(t, hostinfo.in.Load())
 
 	// Do a traffic check tick, should not be pending deletion but should not have any in/out packets recorded
 	nc.doTrafficCheck(hostinfo.localIndexId, p, nb, out, time.Now())
-	assert.False(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.False(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 
 	// Do another traffic check tick, this host should be pending deletion now
 	nc.Out(hostinfo)
-	assert.True(t, hostinfo.sentSinceCheck())
+	assert.True(t, hostinfo.out.Load())
 	nc.doTrafficCheck(hostinfo.localIndexId, p, nb, out, time.Now())
-	assert.True(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.True(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 	assert.Contains(t, nc.hostMap.Indexes, hostinfo.localIndexId)
 	assert.Contains(t, nc.hostMap.Hosts, hostinfo.vpnAddrs[0])
 
@@ -168,33 +168,33 @@ func Test_NewConnectionManagerTest2(t *testing.T) {
 	// We saw traffic out to vpnIp
 	nc.Out(hostinfo)
 	nc.In(hostinfo)
-	assert.True(t, (hostinfo.state.Load()&stateIn != 0))
-	assert.True(t, hostinfo.sentSinceCheck())
-	assert.False(t, hostinfo.isPendingDeletion())
+	assert.True(t, hostinfo.in.Load())
+	assert.True(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.pendingDeletion.Load())
 	assert.Contains(t, nc.hostMap.Hosts, hostinfo.vpnAddrs[0])
 	assert.Contains(t, nc.hostMap.Indexes, hostinfo.localIndexId)
 
 	// Do a traffic check tick, should not be pending deletion but should not have any in/out packets recorded
 	nc.doTrafficCheck(hostinfo.localIndexId, p, nb, out, time.Now())
-	assert.False(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.False(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 
 	// Do another traffic check tick, this host should be pending deletion now
 	nc.Out(hostinfo)
 	nc.doTrafficCheck(hostinfo.localIndexId, p, nb, out, time.Now())
-	assert.True(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.True(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 	assert.Contains(t, nc.hostMap.Indexes, hostinfo.localIndexId)
 	assert.Contains(t, nc.hostMap.Hosts, hostinfo.vpnAddrs[0])
 
 	// We saw traffic, should no longer be pending deletion
 	nc.In(hostinfo)
 	nc.doTrafficCheck(hostinfo.localIndexId, p, nb, out, time.Now())
-	assert.False(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.False(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 	assert.Contains(t, nc.hostMap.Indexes, hostinfo.localIndexId)
 	assert.Contains(t, nc.hostMap.Hosts, hostinfo.vpnAddrs[0])
 }
@@ -253,31 +253,31 @@ func Test_NewConnectionManager_DisconnectInactive(t *testing.T) {
 	// Do a traffic check tick, in and out should be cleared but should not be pending deletion
 	nc.Out(hostinfo)
 	nc.In(hostinfo)
-	assert.True(t, hostinfo.sentSinceCheck())
-	assert.True(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.True(t, hostinfo.out.Load())
+	assert.True(t, hostinfo.in.Load())
 
 	now := time.Now()
 	decision, _, _ := nc.makeTrafficDecision(hostinfo.localIndexId, now)
 	assert.Equal(t, tryRehandshake, decision)
 	assert.Equal(t, now, hostinfo.lastUsed)
-	assert.False(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.False(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 
 	decision, _, _ = nc.makeTrafficDecision(hostinfo.localIndexId, now.Add(time.Second*5))
 	assert.Equal(t, doNothing, decision)
 	assert.Equal(t, now, hostinfo.lastUsed)
-	assert.False(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.False(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 
 	// Do another traffic check tick, should still not be pending deletion
 	decision, _, _ = nc.makeTrafficDecision(hostinfo.localIndexId, now.Add(time.Second*10))
 	assert.Equal(t, doNothing, decision)
 	assert.Equal(t, now, hostinfo.lastUsed)
-	assert.False(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.False(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 	assert.Contains(t, nc.hostMap.Indexes, hostinfo.localIndexId)
 	assert.Contains(t, nc.hostMap.Hosts, hostinfo.vpnAddrs[0])
 
@@ -285,9 +285,9 @@ func Test_NewConnectionManager_DisconnectInactive(t *testing.T) {
 	decision, _, _ = nc.makeTrafficDecision(hostinfo.localIndexId, now.Add(time.Minute*10))
 	assert.Equal(t, closeTunnel, decision)
 	assert.Equal(t, now, hostinfo.lastUsed)
-	assert.False(t, hostinfo.isPendingDeletion())
-	assert.False(t, hostinfo.sentSinceCheck())
-	assert.False(t, (hostinfo.state.Load()&stateIn != 0))
+	assert.False(t, hostinfo.pendingDeletion.Load())
+	assert.False(t, hostinfo.out.Load())
+	assert.False(t, hostinfo.in.Load())
 	assert.Contains(t, nc.hostMap.Indexes, hostinfo.localIndexId)
 	assert.Contains(t, nc.hostMap.Hosts, hostinfo.vpnAddrs[0])
 }

control.go

@@ -212,7 +212,7 @@ func (c *Control) RebindUDPServer() {
 	c.f.lightHouse.SendUpdate()
 
 	// Let the main interface know that we rebound so that underlying tunnels know to trigger punches from their remotes
-	c.f.rebindEpoch.Add(1)
+	c.f.rebindCount++
 }
 
 // ListHostmapHosts returns details about the actual or pending (handshaking) hostmap by vpn ip

go.mod

@@ -7,7 +7,6 @@ require (
 	filippo.io/bigmod v0.1.0
 	github.com/anmitsu/go-shlex v0.0.0-20200514113438-38f4b401e2be
 	github.com/armon/go-radix v1.0.0
-	github.com/cyberdelia/go-metrics-graphite v0.0.0-20161219230853-39f87cc3b432
 	github.com/flynn/noise v1.1.0
 	github.com/gaissmai/bart v0.28.0
 	github.com/gogo/protobuf v1.3.2

go.sum

@@ -19,8 +19,6 @@ github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6r
 github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
-github.com/cyberdelia/go-metrics-graphite v0.0.0-20161219230853-39f87cc3b432 h1:M5QgkYacWj0Xs8MhpIK/5uwU02icXpEoSo9sM2aRCps=
-github.com/cyberdelia/go-metrics-graphite v0.0.0-20161219230853-39f87cc3b432/go.mod h1:xwIwAxMvYnVrGJPe2FKx5prTrnAjGOD8zvDOnxnrrkM=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

graphite.go

@@ -0,0 +1,117 @@
+package nebula
+
+// This file is a trimmed, inlined copy of the graphite exporter from
+// github.com/cyberdelia/go-metrics-graphite, retaining only the Config type and
+// the Once entrypoint that Nebula uses. The upstream package has been
+// unmaintained for 10+ years, so it was vendored here to drop the dependency.
+// See https://github.com/slackhq/nebula/issues/1831.
+//
+// Copyright 2015 Timothée Peignier. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+//  1. Redistributions of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//
+//  2. Redistributions in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/rcrowley/go-metrics"
+)
+
+// graphiteConfigExport provides a container with configuration parameters for
+// the Graphite exporter.
+type graphiteConfigExport struct {
+	Addr          *net.TCPAddr     // Network address to connect to
+	Registry      metrics.Registry // Registry to be exported
+	FlushInterval time.Duration    // Flush interval
+	DurationUnit  time.Duration    // Time conversion unit for durations
+	Prefix        string           // Prefix to be prepended to metric names
+	Percentiles   []float64        // Percentiles to export from timers and histograms
+}
+
+// graphiteOnce performs a single submission to Graphite, returning a non-nil
+// error on failed connections.
+func graphiteOnce(c graphiteConfigExport) error {
+	now := time.Now().Unix()
+	du := float64(c.DurationUnit)
+	flushSeconds := float64(c.FlushInterval) / float64(time.Second)
+	conn, err := net.DialTCP("tcp", nil, c.Addr)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+	w := bufio.NewWriter(conn)
+	c.Registry.Each(func(name string, i any) {
+		switch metric := i.(type) {
+		case metrics.Counter:
+			count := metric.Count()
+			fmt.Fprintf(w, "%s.%s.count %d %d\n", c.Prefix, name, count, now)
+			fmt.Fprintf(w, "%s.%s.count_ps %.2f %d\n", c.Prefix, name, float64(count)/flushSeconds, now)
+		case metrics.Gauge:
+			fmt.Fprintf(w, "%s.%s.value %d %d\n", c.Prefix, name, metric.Value(), now)
+		case metrics.GaugeFloat64:
+			fmt.Fprintf(w, "%s.%s.value %f %d\n", c.Prefix, name, metric.Value(), now)
+		case metrics.Histogram:
+			h := metric.Snapshot()
+			ps := h.Percentiles(c.Percentiles)
+			fmt.Fprintf(w, "%s.%s.count %d %d\n", c.Prefix, name, h.Count(), now)
+			fmt.Fprintf(w, "%s.%s.min %d %d\n", c.Prefix, name, h.Min(), now)
+			fmt.Fprintf(w, "%s.%s.max %d %d\n", c.Prefix, name, h.Max(), now)
+			fmt.Fprintf(w, "%s.%s.mean %.2f %d\n", c.Prefix, name, h.Mean(), now)
+			fmt.Fprintf(w, "%s.%s.std-dev %.2f %d\n", c.Prefix, name, h.StdDev(), now)
+			for psIdx, psKey := range c.Percentiles {
+				key := strings.Replace(strconv.FormatFloat(psKey*100.0, 'f', -1, 64), ".", "", 1)
+				fmt.Fprintf(w, "%s.%s.%s-percentile %.2f %d\n", c.Prefix, name, key, ps[psIdx], now)
+			}
+		case metrics.Meter:
+			m := metric.Snapshot()
+			fmt.Fprintf(w, "%s.%s.count %d %d\n", c.Prefix, name, m.Count(), now)
+			fmt.Fprintf(w, "%s.%s.one-minute %.2f %d\n", c.Prefix, name, m.Rate1(), now)
+			fmt.Fprintf(w, "%s.%s.five-minute %.2f %d\n", c.Prefix, name, m.Rate5(), now)
+			fmt.Fprintf(w, "%s.%s.fifteen-minute %.2f %d\n", c.Prefix, name, m.Rate15(), now)
+			fmt.Fprintf(w, "%s.%s.mean %.2f %d\n", c.Prefix, name, m.RateMean(), now)
+		case metrics.Timer:
+			t := metric.Snapshot()
+			ps := t.Percentiles(c.Percentiles)
+			count := t.Count()
+			fmt.Fprintf(w, "%s.%s.count %d %d\n", c.Prefix, name, count, now)
+			fmt.Fprintf(w, "%s.%s.count_ps %.2f %d\n", c.Prefix, name, float64(count)/flushSeconds, now)
+			fmt.Fprintf(w, "%s.%s.min %d %d\n", c.Prefix, name, t.Min()/int64(du), now)
+			fmt.Fprintf(w, "%s.%s.max %d %d\n", c.Prefix, name, t.Max()/int64(du), now)
+			fmt.Fprintf(w, "%s.%s.mean %.2f %d\n", c.Prefix, name, t.Mean()/du, now)
+			fmt.Fprintf(w, "%s.%s.std-dev %.2f %d\n", c.Prefix, name, t.StdDev()/du, now)
+			for psIdx, psKey := range c.Percentiles {
+				key := strings.Replace(strconv.FormatFloat(psKey*100.0, 'f', -1, 64), ".", "", 1)
+				fmt.Fprintf(w, "%s.%s.%s-percentile %.2f %d\n", c.Prefix, name, key, ps[psIdx]/du, now)
+			}
+			fmt.Fprintf(w, "%s.%s.one-minute %.2f %d\n", c.Prefix, name, t.Rate1(), now)
+			fmt.Fprintf(w, "%s.%s.five-minute %.2f %d\n", c.Prefix, name, t.Rate5(), now)
+			fmt.Fprintf(w, "%s.%s.fifteen-minute %.2f %d\n", c.Prefix, name, t.Rate15(), now)
+			fmt.Fprintf(w, "%s.%s.mean-rate %.2f %d\n", c.Prefix, name, t.RateMean(), now)
+		}
+		w.Flush()
+	})
+	return nil
+}

hostmap.go

@@ -238,30 +238,18 @@ const (
 )
 
 type HostInfo struct {
-	// The first cache line is everything the packet paths touch. Grouping them here means a send or receive
-	// pulls in one line instead of two, which is what the layout looked like when state lived at the end.
-
 	remote          atomic.Pointer[netip.AddrPort]
+	remotes         *RemoteList
+	promoteCounter  atomic.Uint32
 	ConnectionState *ConnectionState
-
-	// state holds everything the hot paths need to touch per packet, in one word: whether we have seen traffic
-	// each way since the connection manager last looked, whether it has given up on us, and the
-	// Interface.rebindEpoch this tunnel last sent under. Keeping the epoch here means it survives the traffic
-	// bits being cleared, so a tunnel that has not sent since a rebind still notices when it does.
-	state atomic.Uint32
-
-	promoteCounter atomic.Uint32
-	remoteIndexId  uint32
-	localIndexId   uint32
-	remotes        *RemoteList
+	remoteIndexId   uint32
+	localIndexId    uint32
 
 	// vpnAddrs is a list of vpn addresses assigned to this host that are within our own vpn networks
 	// The host may have other vpn addresses that are outside our
 	// vpn networks but were removed because they are not usable
 	vpnAddrs []netip.Addr
 
-	// Everything below is off the packet path: handshakes, relays, roaming and the connection manager.
-
 	// networks is a combination of specific vpn addresses (not prefixes!) and full unsafe networks assigned to this host.
 	networks   *bart.Table[NetworkType]
 	relayState RelayState
@@ -274,6 +262,11 @@ type HostInfo struct {
 	// This is used to limit lighthouse re-queries in chatty clients
 	nextLHQuery atomic.Int64
 
+	// lastRebindCount is the other side of Interface.rebindCount, if these values don't match then we need to ask LH
+	// for a punch from the remote end of this tunnel. The goal being to prime their conntrack for our traffic just like
+	// with a handshake
+	lastRebindCount int8
+
 	// lastHandshakeTime records the time the remote side told us about at the stage when the handshake was completed locally
 	// Stage 1 packet will contain it if I am a responder, stage 2 packet if I am an initiator
 	// This is used to avoid an attack where a handshake packet is replayed after some time
@@ -282,6 +275,9 @@ type HostInfo struct {
 	lastRoam       time.Time
 	lastRoamRemote netip.AddrPort
 
+	//TODO: in, out, and others might benefit from being an atomic.Int32. We could collapse connectionManager pendingDeletion, relayUsed, and in/out into this 1 thing
+	in, out, pendingDeletion atomic.Bool
+
 	// lastUsed tracks the last time ConnectionManager checked the tunnel and it was in use.
 	// This value will be behind against actual tunnel utilization in the hot path.
 	// This should only be used by the ConnectionManagers ticker routine.
@@ -662,7 +658,7 @@ func (hm *HostMap) unlockedAddHostInfo(hostinfo *HostInfo, f *Interface) {
 	hm.Indexes[hostinfo.localIndexId] = hostinfo
 	hm.RemoteIndexes[hostinfo.remoteIndexId] = hostinfo
 
-	hostinfo.markOut(f.rebindEpoch.Load())
+	hostinfo.out.Store(true)
 	if f.connectionManager != nil { // f.connectionManager is only nil in some unit tests
 		f.connectionManager.trafficTimer.Add(hostinfo.localIndexId, f.connectionManager.checkInterval)
 	}
@@ -763,64 +759,6 @@ func (i *HostInfo) TryPromoteBest(preferredRanges []netip.Prefix, ifce *Interfac
 	}
 }
 
-// Bits within HostInfo.state. Everything above stateEpochShift is the rebind epoch.
-const (
-	stateIn uint32 = 1 << iota
-	stateOut
-	statePendingDeletion
-
-	stateFlags      = stateIn | stateOut | statePendingDeletion
-	stateEpochShift = 3
-)
-
-// markIn records inbound traffic. Reading first keeps the cache line shared on the common path, where the bit
-// is already set.
-func (i *HostInfo) markIn() {
-	if i.state.Load()&stateIn == 0 {
-		i.state.Or(stateIn)
-	}
-}
-
-// markOut records that we sent on this tunnel under the given rebind epoch. It reports whether the epoch moved
-// since our last send, which means the local network changed and we want the far side to punch at us again.
-// The common path is a single load that matches and returns.
-func (i *HostInfo) markOut(epoch uint32) bool {
-	e := epoch << stateEpochShift
-	for {
-		old := i.state.Load()
-		if old&stateOut != 0 && old&^stateFlags == e {
-			return false
-		}
-
-		if i.state.CompareAndSwap(old, old&stateFlags|stateOut|e) {
-			return old&^stateFlags != e
-		}
-	}
-}
-
-// sentSinceCheck reports whether anything has been sent since the connection manager last looked.
-func (i *HostInfo) sentSinceCheck() bool {
-	return i.state.Load()&stateOut != 0
-}
-
-// takeTraffic clears both traffic bits, leaving the epoch alone, and reports what they were.
-func (i *HostInfo) takeTraffic() (in bool, out bool) {
-	old := i.state.And(^(stateIn | stateOut))
-	return old&stateIn != 0, old&stateOut != 0
-}
-
-func (i *HostInfo) setPendingDeletion(v bool) {
-	if v {
-		i.state.Or(statePendingDeletion)
-	} else {
-		i.state.And(^statePendingDeletion)
-	}
-}
-
-func (i *HostInfo) isPendingDeletion() bool {
-	return i.state.Load()&statePendingDeletion != 0
-}
-
 func (i *HostInfo) GetCert() *cert.CachedCertificate {
 	if i.ConnectionState != nil {
 		return i.ConnectionState.peerCert

inside.go

@@ -365,12 +365,17 @@ func (f *Interface) sendNoMetrics(t header.MessageType, st header.MessageSubType
 
 	//l.WithField("trace", string(debug.Stack())).Error("out Header ", &Header{Version, t, st, 0, hostinfo.remoteIndexId, c}, p)
 	out = header.Encode(out, header.Version, t, st, hostinfo.remoteIndexId, c)
-	// We rebound since this tunnel last sent, so the local network moved. Ask the lighthouse to have the far side
-	// punch at where we are now, which primes their conntrack the same way a handshake would.
-	if f.connectionManager.Out(hostinfo) && t != header.CloseTunnel {
+	f.connectionManager.Out(hostinfo)
+
+	// Query our LH if we haven't since the last time we've been rebound, this will cause the remote to punch against
+	// all our addrs and enable a faster roaming.
+	if t != header.CloseTunnel && hostinfo.lastRebindCount != f.rebindCount {
+		//NOTE: there is an update hole if a tunnel isn't used and exactly 256 rebinds occur before the tunnel is
+		// finally used again. This tunnel would eventually be torn down and recreated if this action didn't help.
 		f.lightHouse.QueryServer(hostinfo.vpnAddrs[0])
+		hostinfo.lastRebindCount = f.rebindCount
 		if f.l.Enabled(context.Background(), slog.LevelDebug) {
-			f.l.Debug("Lighthouse update triggered for punch due to rebind epoch",
+			f.l.Debug("Lighthouse update triggered for punch due to rebind counter",
 				"vpnAddrs", hostinfo.vpnAddrs,
 			)
 		}

interface.go

@@ -82,10 +82,8 @@ type Interface struct {
 	sendRecvErrorConfig   recvErrorConfig
 	acceptRecvErrorConfig recvErrorConfig
 
-	// rebindEpoch bumps every time the udp listener is rebound, which means the local network moved. Tunnels
-	// compare it against their own copy to decide they need a punch from the far side. Read on every send, only
-	// written on a rebind, so the cache line stays shared across the routines.
-	rebindEpoch atomic.Uint32
+	// rebindCount is used to decide if an active tunnel should trigger a punch notification through a lighthouse
+	rebindCount int8
 	version     string
 
 	conntrackCacheTimeout time.Duration

stats.go

@@ -13,7 +13,6 @@ import (
 	"sync/atomic"
 	"time"
 
-	graphite "github.com/cyberdelia/go-metrics-graphite"
 	mp "github.com/nbrownus/go-metrics-prometheus"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
@@ -253,7 +252,7 @@ func (s *statsServer) buildRuntime(cfg statsConfig) ([]func(), *http.Server) {
 		// loadStatsConfig already resolved and validated the address; re-parse
 		// the resolved form (no DNS lookup) to get a *net.TCPAddr.
 		addr, _ := net.ResolveTCPAddr(cfg.graphite.protocol, cfg.graphite.resolvedAddr)
-		gcfg := graphite.Config{
+		gcfg := graphiteConfigExport{
 			Addr:          addr,
 			Registry:      metrics.DefaultRegistry,
 			FlushInterval: cfg.interval,
@@ -262,7 +261,7 @@ func (s *statsServer) buildRuntime(cfg statsConfig) ([]func(), *http.Server) {
 			Percentiles:   []float64{0.5, 0.75, 0.95, 0.99, 0.999},
 		}
 		captureFns = append(captureFns, func() {
-			if err := graphite.Once(gcfg); err != nil {
+			if err := graphiteOnce(gcfg); err != nil {
 				s.l.Error("Graphite export failed", "error", err)
 			}
 		})

stats_test.go

@@ -371,7 +371,7 @@ func waitForListening(t *testing.T, addr string) {
 	})
 }
 
-// graphiteSink is a minimal TCP accept-and-discard server so graphite.Once
+// graphiteSink is a minimal TCP accept-and-discard server so graphiteOnce
 // calls in tests don't spam error logs or wedge on connection refused.
 type graphiteSink struct {
 	ln net.Listener