fix: ipv6 compatibility issues fixes 20250809 (#23061)

Co-authored-by: Qiu Jian <qiujian@yunionyun.com>

go.mod

@@ -96,12 +96,12 @@ require (
 	k8s.io/cri-api v0.22.17
 	k8s.io/klog/v2 v2.20.0
 	moul.io/http2curl/v2 v2.3.0
-	yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250806100640-5372b7ebd1a4
+	yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250807082423-7edaa2517e8e
 	yunion.io/x/executor v0.0.0-20250518005516-5402e9e0bed0
 	yunion.io/x/jsonutils v1.0.1-0.20250507052344-1abcf4f443b1
 	yunion.io/x/log v1.0.1-0.20240305175729-7cf2d6cd5a91
 	yunion.io/x/ovsdb v0.0.0-20230306173834-f164f413a900
-	yunion.io/x/pkg v1.10.4-0.20250805171825-2431e10f90a9
+	yunion.io/x/pkg v1.10.4-0.20250810004221-0a408931e156
 	yunion.io/x/s3cli v0.0.0-20241221171442-1c11599d28e1
 	yunion.io/x/sqlchemy v1.1.3-0.20250806073422-e37f5197cec0
 	yunion.io/x/structarg v0.0.0-20231017124457-df4d5009457c

go.sum

@@ -1408,8 +1408,8 @@ sigs.k8s.io/structured-merge-diff/v4 v4.0.1/go.mod h1:bJZC9H9iH24zzfZ/41RGcq60oK
 sigs.k8s.io/yaml v1.1.0/go.mod h1:UJmg0vDUVViEyp3mgSv9WPwZCDxu4rQW1olrI1uml+o=
 sigs.k8s.io/yaml v1.2.0 h1:kr/MCeFWJWTwyaHoR9c8EjH9OumOmoF9YGiZd7lFm/Q=
 sigs.k8s.io/yaml v1.2.0/go.mod h1:yfXDCHCao9+ENCvLSE62v9VSji2MKu5jeNfTrofGhJc=
-yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250806100640-5372b7ebd1a4 h1:4/tNKXpaHh0CHG3jt/vFIGIlbHMZ0ceK1iPMvSzwYCU=
-yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250806100640-5372b7ebd1a4/go.mod h1:FXxAEbdNfWXX9gjME3K2nJhkydHY5EKEUZb+RLEzVwQ=
+yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250807082423-7edaa2517e8e h1:ShOTidpZjZKTiIeFEXi0TXA/7j7FB95FiiF09nM1tQ8=
+yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250807082423-7edaa2517e8e/go.mod h1:FXxAEbdNfWXX9gjME3K2nJhkydHY5EKEUZb+RLEzVwQ=
 yunion.io/x/executor v0.0.0-20250518005516-5402e9e0bed0 h1:msG4SiDSVU7CrXH06WuHlNEZXIooTcmNbfrIGHuIHBU=
 yunion.io/x/executor v0.0.0-20250518005516-5402e9e0bed0/go.mod h1:Uxuou9WQIeJXNpy7t2fPLL0BYLvLiMvGQwY7Qc6aSws=
 yunion.io/x/jsonutils v0.0.0-20190625054549-a964e1e8a051/go.mod h1:4N0/RVzsYL3kH3WE/H1BjUQdFiWu50JGCFQuuy+Z634=
@@ -1423,8 +1423,8 @@ yunion.io/x/ovsdb v0.0.0-20230306173834-f164f413a900 h1:Hu/4ERvoWaN6aiFs4h4/yvVB
 yunion.io/x/ovsdb v0.0.0-20230306173834-f164f413a900/go.mod h1:0vLkNEhlmA64HViPBAnSTUMrx5QP1CLsxXmxDKQ80tc=
 yunion.io/x/pkg v0.0.0-20190620104149-945c25821dbf/go.mod h1:t6rEGG2sQ4J7DhFxSZVOTjNd0YO/KlfWQyK1W4tog+E=
 yunion.io/x/pkg v0.0.0-20190628082551-f4033ba2ea30/go.mod h1:t6rEGG2sQ4J7DhFxSZVOTjNd0YO/KlfWQyK1W4tog+E=
-yunion.io/x/pkg v1.10.4-0.20250805171825-2431e10f90a9 h1:8NuoKUPb3sHigChE6Mz6Nf9aZvM/TvORueIZAMYfPK0=
-yunion.io/x/pkg v1.10.4-0.20250805171825-2431e10f90a9/go.mod h1:0Bwxqd9MA3ACi119/l02FprY/o9gHahmYC2bsSbnVpM=
+yunion.io/x/pkg v1.10.4-0.20250810004221-0a408931e156 h1:ONxzK7UJhLKrDUM7vH6EQPNhwkCXaWDtmC67fF12/RE=
+yunion.io/x/pkg v1.10.4-0.20250810004221-0a408931e156/go.mod h1:0Bwxqd9MA3ACi119/l02FprY/o9gHahmYC2bsSbnVpM=
 yunion.io/x/s3cli v0.0.0-20241221171442-1c11599d28e1 h1:1KJ3YYinydPHpDEQRXdr/T8SYcKZ5Er+m489H+PnaQ4=
 yunion.io/x/s3cli v0.0.0-20241221171442-1c11599d28e1/go.mod h1:0iFKpOs1y4lbCxeOmq3Xx/0AcQoewVPwj62eRluioEo=
 yunion.io/x/sqlchemy v1.1.3-0.20250806073422-e37f5197cec0 h1:Eha/ywh4foMJm7VJ8ibFOi+WPHacuTWtosAGpOld5vo=

pkg/apis/compute/guestnetwork.go

@@ -36,6 +36,14 @@ type GuestnetworkDetails struct {
 	EipAddr string `json:"eip_addr"`
 
 	NetworkAddresses []NetworkAddrConf `json:"network_addresses"`
+
+	GuestIpMask int8 `json:"guest_ip_mask"`
+	// 网关地址
+	GuestGateway string `json:"guest_gateway"`
+
+	GuestIp6Mask uint8 `json:"guest_ip6_mask"`
+	// 网关地址
+	GuestGateway6 string `json:"guest_gateway6"`
 }
 
 type GuestnetworkShortDesc struct {
@@ -58,6 +66,8 @@ type GuestnetworkShortDesc struct {
 	SubIps string `json:"sub_ips"`
 	// 端口映射
 	PortMappings GuestPortMappings `json:"port_mappings"`
+
+	IsDefault bool `json:"is_default"`
 }
 
 type GuestnetworkListInput struct {

pkg/cloudproxy/agent/worker/worker.go

@@ -120,7 +120,7 @@ func (w *Worker) initProxyAgent_(ctx context.Context) error {
 	)
 	if agentDetail.BindAddr == "" || !bindAddrExist(bindAddr) {
 		var err error
-		bindAddr, err = netutils2.MyIP()
+		bindAddr, err = netutils2.MyIPSmart()
 		if err != nil {
 			return errors.Wrap(err, "find bind Addr")
 		}

pkg/compute/models/guest_queries.go

@@ -571,6 +571,8 @@ func fetchGuestNICs(ctx context.Context, guestIds []string, virtual tristate.Tri
 
 		gnwq.Field("port_mappings"),
 
+		gnwq.Field("is_default"),
+
 		wirq.Field("vpc_id"),
 		subIP.Field("sub_ips"),
 	)

pkg/compute/models/guestnetworks.go

@@ -175,6 +175,10 @@ func (manager *SGuestnetworkManager) FetchCustomizeColumns(
 		if net, ok := netMap[netIds[i]]; ok {
 			rows[i].Network = net.Name
 			rows[i].WireId = net.WireId
+			rows[i].GuestIpMask = net.GuestIpMask
+			rows[i].GuestGateway = net.GuestGateway
+			rows[i].GuestIp6Mask = net.GuestIp6Mask
+			rows[i].GuestGateway6 = net.GuestGateway6
 		}
 	}
 
@@ -408,7 +412,7 @@ func (manager *SGuestnetworkManager) newGuestNetwork(
 		}
 	}
 
-	if vpc.Id != api.DEFAULT_VPC_ID && provider == api.CLOUD_PROVIDER_ONECLOUD && len(gn.IpAddr) > 0 || len(gn.Ip6Addr) > 0 {
+	if vpc.Id != api.DEFAULT_VPC_ID && provider == api.CLOUD_PROVIDER_ONECLOUD && (len(gn.IpAddr) > 0 || len(gn.Ip6Addr) > 0) {
 		var err error
 		GuestnetworkManager.lockAllocMappedAddr(ctx)
 		defer GuestnetworkManager.unlockAllocMappedAddr(ctx)

pkg/compute/models/networks.go

@@ -3294,13 +3294,37 @@ func (manager *SNetworkManager) PerformTryCreateNetwork(ctx context.Context, use
 	if len(input.Ip) == 0 {
 		return nil, httperrors.NewMissingParameterError("ip")
 	}
-	ipV4, err := netutils.NewIPV4Addr(input.Ip)
-	if err != nil {
-		return nil, httperrors.NewInputParameterError("ip")
-	}
+
+	var ipV4, ipV4NetAddr netutils.IPV4Addr
+	var ipV6, ipV6NetAddr netutils.IPV6Addr
+	var err error
+
 	if input.Mask == 0 {
 		return nil, httperrors.NewMissingParameterError("mask")
 	}
+
+	if regutils.MatchIP4Addr(input.Ip) {
+		ipV4, err = netutils.NewIPV4Addr(input.Ip)
+		if err != nil {
+			return nil, errors.Wrapf(err, "invalid ipv4 address %s", input.Ip)
+		}
+		if ipV4.IsZero() {
+			return nil, errors.Wrapf(errors.ErrInvalidFormat, "invalid ipv4 address %s", input.Ip)
+		}
+		ipV4NetAddr = ipV4.NetAddr(int8(input.Mask))
+	} else if regutils.MatchIP6Addr(input.Ip) {
+		ipV6, err = netutils.NewIPV6Addr(input.Ip)
+		if err != nil {
+			return nil, errors.Wrapf(err, "invalid ipv6 address %s", input.Ip)
+		}
+		if ipV6.IsZero() {
+			return nil, errors.Wrapf(errors.ErrInvalidFormat, "invalid ipv6 address %s", input.Ip)
+		}
+		ipV6NetAddr = ipV6.NetAddr(uint8(input.Mask))
+	} else {
+		return nil, errors.Wrapf(errors.ErrInvalidFormat, "invalid ip address %s", input.Ip)
+	}
+
 	if len(input.ServerType) == 0 {
 		return nil, httperrors.NewMissingParameterError("server_type")
 	}
@@ -3312,12 +3336,16 @@ func (manager *SNetworkManager) PerformTryCreateNetwork(ctx context.Context, use
 	}
 
 	var (
-		ipV4NetAddr = ipV4.NetAddr(int8(input.Mask))
-		nm          *SNetwork
-		matched     bool
+		nm      *SNetwork
+		matched bool
 	)
 
-	q := NetworkManager.Query().Equals("server_type", input.ServerType).Equals("guest_ip_mask", input.Mask)
+	q := NetworkManager.Query().Equals("server_type", input.ServerType)
+	if !ipV4.IsZero() {
+		q = q.Equals("guest_ip_mask", input.Mask)
+	} else if !ipV6.IsZero() {
+		q = q.Equals("guest_ip6_mask", input.Mask)
+	}
 
 	listQuery := api.NetworkListInput{}
 	err = query.Unmarshal(&listQuery)
@@ -3350,14 +3378,27 @@ func (manager *SNetworkManager) PerformTryCreateNetwork(ctx context.Context, use
 			return nil, err
 		}
 		n := item.(*SNetwork)
-		if n.GetIPRange().Contains(ipV4) {
-			nm = n
-			matched = true
-			break
-		} else if nIpV4, _ := netutils.NewIPV4Addr(n.GuestIpStart); nIpV4.NetAddr(n.GuestIpMask) == ipV4NetAddr {
-			nm = n
-			matched = false
-			break
+
+		if !ipV4.IsZero() {
+			if n.getIPRange().Contains(ipV4) {
+				nm = n
+				matched = true
+				break
+			} else if nIpV4, _ := netutils.NewIPV4Addr(n.GuestIpStart); nIpV4.NetAddr(n.GuestIpMask) == ipV4NetAddr {
+				nm = n
+				matched = false
+				break
+			}
+		} else if !ipV6.IsZero() {
+			if n.getIPRange6().Contains(ipV6) {
+				nm = n
+				matched = true
+				break
+			} else if nIpV6, _ := netutils.NewIPV6Addr(n.GuestIp6Start); nIpV6.NetAddr(n.GuestIp6Mask) == ipV6NetAddr {
+				nm = n
+				matched = false
+				break
+			}
 		}
 	}
 
@@ -3369,13 +3410,20 @@ func (manager *SNetworkManager) PerformTryCreateNetwork(ctx context.Context, use
 	ret.Set("find_matched", jsonutils.JSONTrue)
 	ret.Set("wire_id", jsonutils.NewString(nm.WireId))
 	if !matched {
-		log.Infof("Find same subnet network %s %s/%d", nm.Name, nm.GuestGateway, nm.GuestIpMask)
+		log.Infof("Find same subnet network %s %s/%d %s/%d", nm.Name, nm.GuestGateway, nm.GuestIpMask, nm.GuestGateway6, nm.GuestIp6Mask)
 		newNetwork := new(SNetwork)
 		newNetwork.SetModelManager(NetworkManager, newNetwork)
-		newNetwork.GuestIpStart = input.Ip
-		newNetwork.GuestIpEnd = input.Ip
-		newNetwork.GuestGateway = nm.GuestGateway
-		newNetwork.GuestIpMask = int8(input.Mask)
+		if !ipV4.IsZero() {
+			newNetwork.GuestIpStart = ipV4.String()
+			newNetwork.GuestIpEnd = ipV4.String()
+			newNetwork.GuestGateway = nm.GuestGateway
+			newNetwork.GuestIpMask = int8(input.Mask)
+		} else if !ipV6.IsZero() {
+			newNetwork.GuestIp6Start = ipV6.String()
+			newNetwork.GuestIp6End = ipV6.String()
+			newNetwork.GuestGateway6 = nm.GuestGateway6
+			newNetwork.GuestIp6Mask = uint8(input.Mask)
+		}
 		newNetwork.GuestDns = nm.GuestDns
 		newNetwork.GuestDhcp = nm.GuestDhcp
 		newNetwork.GuestNtp = nm.GuestNtp

pkg/compute/models/vpcs.go

@@ -997,8 +997,8 @@ func (manager *SVpcManager) ValidateCreateData(
 		return input, err
 	}
 
-	if region.GetDriver().IsVpcCreateNeedInputCidr() && len(input.CidrBlock) == 0 {
-		return input, httperrors.NewMissingParameterError("cidr")
+	if region.GetDriver().IsVpcCreateNeedInputCidr() && len(input.CidrBlock) == 0 && len(input.CidrBlock6) == 0 {
+		return input, httperrors.NewMissingParameterError("cidr_block or cidr_block6")
 	}
 
 	keys := GetVpcQuotaKeysFromCreateInput(ownerId, input)

pkg/compute/regiondrivers/kvm.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"sort"
 	"strconv"
+	"strings"
 
 	"yunion.io/x/cloudmux/pkg/cloudprovider"
 	"yunion.io/x/jsonutils"
@@ -517,9 +518,15 @@ func (self *SKVMRegionDriver) RequestDeleteLoadbalancerListenerRule(ctx context.
 }
 
 func (self *SKVMRegionDriver) ValidateCreateVpcData(ctx context.Context, userCred mcclient.TokenCredential, input api.VpcCreateInput) (api.VpcCreateInput, error) {
-	if !utils.IsInStringArray(input.CidrBlock, []string{"192.168.0.0/16", "10.0.0.0/8", "172.16.0.0/12"}) {
+	if len(input.CidrBlock) > 0 && !utils.IsInStringArray(input.CidrBlock, []string{"192.168.0.0/16", "10.0.0.0/8", "172.16.0.0/12"}) {
 		return input, httperrors.NewInputParameterError("Invalid cidr_block, want 192.168.0.0/16|10.0.0.0/8|172.16.0.0/12, got %s", input.CidrBlock)
 	}
+	if len(input.CidrBlock6) > 0 {
+		input.CidrBlock6 = strings.ToLower(input.CidrBlock6)
+		if !strings.HasPrefix(input.CidrBlock6, "fd") {
+			return input, httperrors.NewInputParameterError("Invalid ipv6 cidr_block, %s outside of IPv6 private unicast address range fd00::/8", input.CidrBlock6)
+		}
+	}
 	return input, nil
 }
 

pkg/hostman/hostinfo/hostbridge/hostbridge.go

@@ -344,12 +344,12 @@ func (d *SBaseBridgeDriver) ConfirmToConfig() (bool, string, error) {
 			if d.bridge.Addr != d.ip {
 				return false, "", fmt.Errorf("bridge %s IP %s is not expected IP %s, mismatch", d.bridge, d.bridge.Addr, d.ip)
 			}
-		} else if len(d.ip6) == 0 {
+		} else {
 			if d.inter != nil && len(d.inter.Addr) > 0 {
 				return false, "", fmt.Errorf("interface %s should have no address", d.inter)
 			}
-			if len(d.bridge.Addr) == 0 {
-				return false, "", fmt.Errorf("bridge %s should have 169.254.0.0/16 address", d.bridge)
+			if len(d.bridge.Addr) > 0 {
+				return false, "", fmt.Errorf("bridge %s (%s) should have no ipv4 address", d.bridge, d.bridge.Addr)
 			}
 			if !d.bridge.IsSecretInterface() {
 				return false, "", fmt.Errorf("%s should have address in 169.254.0.0/16", d.bridge)

pkg/hostman/hostinfo/hostdhcp/icmp6handlers.go

@@ -113,9 +113,9 @@ func (s *SGuestDHCP6Server) sendRouterAdvertisement(solicitation *icmp6.SRouterS
 		gwMac := gwMacObj.(net.HardwareAddr)
 
 		pref := icmp6.PreferenceMedium
-		//if conf.IsDefaultGW {
-		//	pref = icmp6.PreferenceHigh
-		//}
+		if conf.IsDefaultGW {
+			pref = icmp6.PreferenceHigh
+		}
 
 		_, ipnet, err := net.ParseCIDR(fmt.Sprintf("%s/%d", conf.ClientIP6, conf.PrefixLen6))
 		if err != nil {

pkg/lbagent/api.go

@@ -308,7 +308,7 @@ func (h *ApiHelper) agentUpdateSeen(ctx context.Context) *computemodels.SLoadbal
 }
 
 func (h *ApiHelper) newAgentHbParams(ctx context.Context) (*jsonutils.JSONDict, error) {
-	ip, err := netutils2.MyIP()
+	ip, err := netutils2.MyIPSmart()
 	if err != nil {
 		return nil, err
 	}

pkg/util/netutils2/netutils.go

@@ -18,7 +18,6 @@ import (
 	"bytes"
 	"fmt"
 	"net"
-	"reflect"
 	"strconv"
 	"strings"
 	"time"
@@ -447,6 +446,7 @@ type SNetInterface struct {
 	Addr6 string
 	Mask6 net.IPMask
 
+	Addr4LinkLocal string
 	Addr6LinkLocal string
 
 	Mtu int
@@ -520,10 +520,9 @@ func (n *SNetInterface) FetchConfig2(expectIp string, expectIp6 string) {
 		for _, addr := range addrs {
 			if ipnet, ok := addr.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
 				if ipnet.IP.To4() != nil {
-					if len(expectIp) == 0 && n.Addr == "" && strings.HasPrefix(ipnet.IP.To4().String(), SECRET_PREFIX) {
-						continue
-					}
-					if (len(expectIp) > 0 && ipnet.IP.String() == expectIp) || (len(expectIp) == 0 && n.Addr == "") {
+					if strings.HasPrefix(ipnet.IP.To4().String(), SECRET_PREFIX) {
+						n.Addr4LinkLocal = ipnet.IP.String()
+					} else if (len(expectIp) > 0 && ipnet.IP.String() == expectIp) || (len(expectIp) == 0 && n.Addr == "") {
 						n.Addr = ipnet.IP.String()
 						n.Mask = ipnet.Mask
 					}
@@ -603,21 +602,21 @@ func (n *SNetInterface) SetupGso(on bool) {
 }
 
 func (n *SNetInterface) IsSecretInterface() bool {
-	return n.IsSecretAddress(n.Addr, n.Mask)
+	return n.Addr4LinkLocal != "" && n.Addr == ""
 }
 
 func (n *SNetInterface) IsSecretInterface6() bool {
 	return n.Addr6LinkLocal != "" && n.Addr6 == ""
 }
 
-func (n *SNetInterface) IsSecretAddress(addr string, mask []byte) bool {
+/*func (n *SNetInterface) IsSecretAddress(addr string, mask []byte) bool {
 	log.Infof("MASK --- %s", mask)
 	if reflect.DeepEqual(mask, SECRET_MASK) && strings.HasPrefix(addr, SECRET_PREFIX) {
 		return true
 	} else {
 		return false
 	}
-}
+}*/
 
 func GetSecretInterfaceAddress() (string, int) {
 	addr := fmt.Sprintf("%s.%d.1", SECRET_PREFIX, secretInterfaceIndex)

pkg/vpcagent/ovn/worker.go

@@ -122,6 +122,7 @@ func (w *Worker) run(ctx context.Context, mss *agentmodels.ModelSets) (err error
 	} else {
 		dbUrl = db
 	}
+	log.Infof("ovn: connect to ovn north database %s", dbUrl)
 
 	ovnnbctl := ovnutil.NewOvnNbCtl(dbUrl)
 	ovndb, err := DumpOVNNorthbound(ctx, ovnnbctl)

vendor/modules.txt

@@ -1852,7 +1852,7 @@ sigs.k8s.io/structured-merge-diff/v4/value
 # sigs.k8s.io/yaml v1.2.0
 ## explicit; go 1.12
 sigs.k8s.io/yaml
-# yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250806100640-5372b7ebd1a4
+# yunion.io/x/cloudmux v0.3.10-0-alpha.1.0.20250807082423-7edaa2517e8e
 ## explicit; go 1.21
 yunion.io/x/cloudmux/pkg/apis
 yunion.io/x/cloudmux/pkg/apis/billing
@@ -1949,7 +1949,7 @@ yunion.io/x/log/hooks
 yunion.io/x/ovsdb/cli_util
 yunion.io/x/ovsdb/schema/ovn_nb
 yunion.io/x/ovsdb/types
-# yunion.io/x/pkg v1.10.4-0.20250805171825-2431e10f90a9
+# yunion.io/x/pkg v1.10.4-0.20250810004221-0a408931e156
 ## explicit; go 1.18
 yunion.io/x/pkg/appctx
 yunion.io/x/pkg/errors

vendor/yunion.io/x/cloudmux/pkg/multicloud/esxi/virtualmachine.go

@@ -682,12 +682,11 @@ func (svm *SVirtualMachine) doUnregister(ctx context.Context) error {
 }
 
 func (svm *SVirtualMachine) DeleteVM(ctx context.Context) error {
-	err := svm.CheckFileInfo(ctx)
+	err := svm.doDestroy(ctx)
 	if err != nil {
-		log.Errorf("CheckFileInfo %s error: %v", svm.GetName(), err)
 		return svm.doUnregister(ctx)
 	}
-	return svm.doDestroy(ctx)
+	return nil
 }
 
 func (svm *SVirtualMachine) doDetachAndDeleteDisk(ctx context.Context, vdisk *SVirtualDisk) error {

vendor/yunion.io/x/pkg/util/netutils/ipv6.go

@@ -363,6 +363,15 @@ func (addr IPV6Addr) Ge(addr2 IPV6Addr) bool {
 	return !addr.Lt(addr2)
 }
 
+func (addr IPV6Addr) IsZero() bool {
+	for _, v := range addr {
+		if v != 0 {
+			return false
+		}
+	}
+	return true
+}
+
 type IPV6AddrRange struct {
 	start IPV6Addr
 	end   IPV6Addr

vendor/yunion.io/x/pkg/util/netutils/netutils.go

@@ -139,6 +139,10 @@ func (addr IPV4Addr) ToMac(prefix string) string {
 	return fmt.Sprintf("%s%02x:%02x:%02x:%02x", prefix, bytes[0], bytes[1], bytes[2], bytes[3])
 }
 
+func (addr IPV4Addr) IsZero() bool {
+	return addr == 0
+}
+
 type IPV4AddrRange struct {
 	start IPV4Addr
 	end   IPV4Addr