diff --git a/config.go b/config.go
index 4eb2846..9245cf0 100644
--- a/config.go
+++ b/config.go
@@ -85,10 +85,11 @@ type network net.IPNet
 
 // UnmarshalText parses the provided byte array into the network receiver
 func (n *network) UnmarshalText(data []byte) error {
-	_, ipnet, err := net.ParseCIDR(string(data))
+	ip, ipnet, err := net.ParseCIDR(string(data))
 	if err != nil {
 		return err
 	}
+	ipnet.IP = ip
 	*n = network(*ipnet)
 	return nil
 }
diff --git a/wg/wireguard.go b/wg/wireguard.go
index d3fe47d..321e04a 100644
--- a/wg/wireguard.go
+++ b/wg/wireguard.go
@@ -64,12 +64,14 @@ func (s *State) assignOverlayAddr(ipnet *net.IPNet, name string) {
 	ip := make([]byte, len(ipnet.IP))
 	copy(ip, []byte(ipnet.IP))
 
-	h := fnv.New128a()
-	h.Write([]byte(name))
-	hb := h.Sum(nil)
+	if ipnet.IP.Mask(ipnet.Mask).Equal(ipnet.IP) {
+		h := fnv.New128a()
+		h.Write([]byte(name))
+		hb := h.Sum(nil)
 
-	for i := 1; i <= (size-bits)/8; i++ {
-		ip[len(ip)-i] = hb[len(hb)-i]
+		for i := 1; i <= (size-bits)/8; i++ {
+			ip[len(ip)-i] = hb[len(hb)-i]
+		}
 	}
 
 	s.OverlayAddr = net.IPNet{