Fix: exclude the broadcast address to fake ip pool

component/fakeip/pool.go

@@ -25,6 +25,7 @@ type Pool struct {
 	max       uint32
 	min       uint32
 	gateway   uint32
+	broadcast uint32
 	offset    uint32
 	mux       sync.Mutex
 	host      *trie.DomainTrie
@@ -82,6 +83,11 @@ func (p *Pool) Gateway() net.IP {
 	return uintToIP(p.gateway)
 }
 
+// Broadcast return broadcast ip
+func (p *Pool) Broadcast() net.IP {
+	return uintToIP(p.broadcast)
+}
+
 // IPNet return raw ipnet
 func (p *Pool) IPNet() *net.IPNet {
 	return p.ipnet
@@ -144,7 +150,7 @@ func New(options Options) (*Pool, error) {
 	min := ipToUint(options.IPNet.IP) + 2
 
 	ones, bits := options.IPNet.Mask.Size()
-	total := 1<<uint(bits-ones) - 2
+	total := 1<<uint(bits-ones) - 3
 
 	if total <= 0 {
 		return nil, errors.New("ipnet don't have valid ip")
@@ -155,6 +161,7 @@ func New(options Options) (*Pool, error) {
 		min:       min,
 		max:       max,
 		gateway:   min - 1,
+		broadcast: max + 1,
 		host:      options.Host,
 		ipnet:     options.IPNet,
 	}

component/resolver/enhancer.go

@@ -10,6 +10,7 @@ type Enhancer interface {
 	FakeIPEnabled() bool
 	MappingEnabled() bool
 	IsFakeIP(net.IP) bool
+	IsFakeBroadcastIP(net.IP) bool
 	IsExistFakeIP(net.IP) bool
 	FindHostByIP(net.IP) (string, bool)
 }
@@ -38,6 +39,14 @@ func IsFakeIP(ip net.IP) bool {
 	return false
 }
 
+func IsFakeBroadcastIP(ip net.IP) bool {
+	if mapper := DefaultHostMapper; mapper != nil {
+		return mapper.IsFakeBroadcastIP(ip)
+	}
+
+	return false
+}
+
 func IsExistFakeIP(ip net.IP) bool {
 	if mapper := DefaultHostMapper; mapper != nil {
 		return mapper.IsExistFakeIP(ip)

dns/enhancer.go

@@ -40,7 +40,19 @@ func (h *ResolverEnhancer) IsFakeIP(ip net.IP) bool {
 	}
 
 	if pool := h.fakePool; pool != nil {
-		return pool.IPNet().Contains(ip) && !pool.Gateway().Equal(ip)
+		return pool.IPNet().Contains(ip) && !pool.Gateway().Equal(ip) && !pool.Broadcast().Equal(ip)
+	}
+
+	return false
+}
+
+func (h *ResolverEnhancer) IsFakeBroadcastIP(ip net.IP) bool {
+	if !h.FakeIPEnabled() {
+		return false
+	}
+
+	if pool := h.fakePool; pool != nil {
+		return pool.Broadcast().Equal(ip)
 	}
 
 	return false