optimize usage of bart (#1395)

Use `bart.Lite` and `.Contains` as suggested by the bart maintainer:

- 9455952eed (commitcomment-155362580)

firewall.go

@@ -53,7 +53,7 @@ type Firewall struct {
 
 	// routableNetworks describes the vpn addresses as well as any unsafe networks issued to us in the certificate.
 	// The vpn addresses are a full bit match while the unsafe networks only match the prefix
-	routableNetworks *bart.Table[struct{}]
+	routableNetworks *bart.Lite
 
 	// assignedNetworks is a list of vpn networks assigned to us in the certificate.
 	assignedNetworks  []netip.Prefix
@@ -125,7 +125,7 @@ type firewallPort map[int32]*FirewallCA
 
 type firewallLocalCIDR struct {
 	Any       bool
-	LocalCIDR *bart.Table[struct{}]
+	LocalCIDR *bart.Lite
 }
 
 // NewFirewall creates a new Firewall object. A TimerWheel is created for you from the provided timeouts.
@@ -148,17 +148,17 @@ func NewFirewall(l *logrus.Logger, tcpTimeout, UDPTimeout, defaultTimeout time.D
 		tmax = defaultTimeout
 	}
 
-	routableNetworks := new(bart.Table[struct{}])
+	routableNetworks := new(bart.Lite)
 	var assignedNetworks []netip.Prefix
 	for _, network := range c.Networks() {
 		nprefix := netip.PrefixFrom(network.Addr(), network.Addr().BitLen())
-		routableNetworks.Insert(nprefix, struct{}{})
+		routableNetworks.Insert(nprefix)
 		assignedNetworks = append(assignedNetworks, network)
 	}
 
 	hasUnsafeNetworks := false
 	for _, n := range c.UnsafeNetworks() {
-		routableNetworks.Insert(n, struct{}{})
+		routableNetworks.Insert(n)
 		hasUnsafeNetworks = true
 	}
 
@@ -431,8 +431,7 @@ func (f *Firewall) Drop(fp firewall.Packet, incoming bool, h *HostInfo, caPool *
 
 	// Make sure remote address matches nebula certificate
 	if h.networks != nil {
-		_, ok := h.networks.Lookup(fp.RemoteAddr)
-		if !ok {
+		if !h.networks.Contains(fp.RemoteAddr) {
 			f.metrics(incoming).droppedRemoteAddr.Inc(1)
 			return ErrInvalidRemoteIP
 		}
@@ -445,8 +444,7 @@ func (f *Firewall) Drop(fp firewall.Packet, incoming bool, h *HostInfo, caPool *
 	}
 
 	// Make sure we are supposed to be handling this local ip address
-	_, ok := f.routableNetworks.Lookup(fp.LocalAddr)
-	if !ok {
+	if !f.routableNetworks.Contains(fp.LocalAddr) {
 		f.metrics(incoming).droppedLocalAddr.Inc(1)
 		return ErrInvalidLocalIP
 	}
@@ -752,7 +750,7 @@ func (fc *FirewallCA) match(p firewall.Packet, c *cert.CachedCertificate, caPool
 func (fr *FirewallRule) addRule(f *Firewall, groups []string, host string, ip, localCIDR netip.Prefix) error {
 	flc := func() *firewallLocalCIDR {
 		return &firewallLocalCIDR{
-			LocalCIDR: new(bart.Table[struct{}]),
+			LocalCIDR: new(bart.Lite),
 		}
 	}
 
@@ -879,7 +877,7 @@ func (flc *firewallLocalCIDR) addRule(f *Firewall, localIp netip.Prefix) error {
 		}
 
 		for _, network := range f.assignedNetworks {
-			flc.LocalCIDR.Insert(network, struct{}{})
+			flc.LocalCIDR.Insert(network)
 		}
 		return nil
 
@@ -888,7 +886,7 @@ func (flc *firewallLocalCIDR) addRule(f *Firewall, localIp netip.Prefix) error {
 		return nil
 	}
 
-	flc.LocalCIDR.Insert(localIp, struct{}{})
+	flc.LocalCIDR.Insert(localIp)
 	return nil
 }
 
@@ -901,8 +899,7 @@ func (flc *firewallLocalCIDR) match(p firewall.Packet, c *cert.CachedCertificate
 		return true
 	}
 
-	_, ok := flc.LocalCIDR.Lookup(p.LocalAddr)
-	return ok
+	return flc.LocalCIDR.Contains(p.LocalAddr)
 }
 
 type rule struct {