Golang nl.DeserializeIfInfomsg函數代碼示例

func linkSubscribe(newNs, curNs netns.NsHandle, ch chan<- LinkUpdate, done <-chan struct{}) error {
	s, err := nl.SubscribeAt(newNs, curNs, syscall.NETLINK_ROUTE, syscall.RTNLGRP_LINK)
	if err != nil {
		return err
	}
	if done != nil {
		go func() {
			<-done
			s.Close()
		}()
	}
	go func() {
		defer close(ch)
		for {
			msgs, err := s.Receive()
			if err != nil {
				return
			}
			for _, m := range msgs {
				ifmsg := nl.DeserializeIfInfomsg(m.Data)
				link, err := LinkDeserialize(m.Data)
				if err != nil {
					return
				}
				ch <- LinkUpdate{IfInfomsg: *ifmsg, Header: m.Header, Link: link}
			}
		}
	}()

	return nil
}

func LinkGetProtinfo(link Link) (Protinfo, error) {
	base := link.Attrs()
	ensureIndex(base)
	var pi Protinfo
	req := nl.NewNetlinkRequest(syscall.RTM_GETLINK, syscall.NLM_F_DUMP)
	msg := nl.NewIfInfomsg(syscall.AF_BRIDGE)
	req.AddData(msg)
	msgs, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	if err != nil {
		return pi, err
	}

	for _, m := range msgs {
		ans := nl.DeserializeIfInfomsg(m)
		if int(ans.Index) != base.Index {
			continue
		}
		attrs, err := nl.ParseRouteAttr(m[ans.Len():])
		if err != nil {
			return pi, err
		}
		for _, attr := range attrs {
			if attr.Attr.Type != syscall.IFLA_PROTINFO|syscall.NLA_F_NESTED {
				continue
			}
			infos, err := nl.ParseRouteAttr(attr.Value)
			if err != nil {
				return pi, err
			}
			var pi Protinfo
			for _, info := range infos {
				switch info.Attr.Type {
				case nl.IFLA_BRPORT_MODE:
					pi.Hairpin = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_GUARD:
					pi.Guard = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_FAST_LEAVE:
					pi.FastLeave = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_PROTECT:
					pi.RootBlock = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_LEARNING:
					pi.Learning = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_UNICAST_FLOOD:
					pi.Flood = byteToBool(info.Value[0])
				}
			}
			return pi, nil
		}
	}
	return pi, fmt.Errorf("Device with index %d not found", base.Index)
}

func matchIfName(ifaceName string) func(m syscall.NetlinkMessage) (bool, error) {
	return func(m syscall.NetlinkMessage) (bool, error) {
		switch m.Header.Type {
		case syscall.RTM_NEWLINK: // receive this type for link 'up'
			ifmsg := nl.DeserializeIfInfomsg(m.Data)
			attrs, err := syscall.ParseNetlinkRouteAttr(&m)
			if err != nil {
				return true, err
			}
			name := ""
			for _, attr := range attrs {
				if attr.Attr.Type == syscall.IFA_LABEL {
					name = string(attr.Value[:len(attr.Value)-1])
				}
			}
			if ifaceName == name && ifmsg.Flags&syscall.IFF_UP != 0 {
				return true, nil
			}
		}
		return false, nil
	}
}

func (h *Handle) LinkGetProtinfo(link Link) (Protinfo, error) {
	base := link.Attrs()
	h.ensureIndex(base)
	var pi Protinfo
	req := h.newNetlinkRequest(syscall.RTM_GETLINK, syscall.NLM_F_DUMP)
	msg := nl.NewIfInfomsg(syscall.AF_BRIDGE)
	req.AddData(msg)
	msgs, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	if err != nil {
		return pi, err
	}

	for _, m := range msgs {
		ans := nl.DeserializeIfInfomsg(m)
		if int(ans.Index) != base.Index {
			continue
		}
		attrs, err := nl.ParseRouteAttr(m[ans.Len():])
		if err != nil {
			return pi, err
		}
		for _, attr := range attrs {
			if attr.Attr.Type != syscall.IFLA_PROTINFO|syscall.NLA_F_NESTED {
				continue
			}
			infos, err := nl.ParseRouteAttr(attr.Value)
			if err != nil {
				return pi, err
			}
			pi = *parseProtinfo(infos)

			return pi, nil
		}
	}
	return pi, fmt.Errorf("Device with index %d not found", base.Index)
}

// linkDeserialize deserializes a raw message received from netlink into
// a link object.
func LinkDeserialize(m []byte) (Link, error) {
	msg := nl.DeserializeIfInfomsg(m)

	attrs, err := nl.ParseRouteAttr(m[msg.Len():])
	if err != nil {
		return nil, err
	}

	base := LinkAttrs{Index: int(msg.Index), RawFlags: msg.Flags, Flags: linkFlags(msg.Flags), EncapType: msg.EncapType()}
	if msg.Flags&syscall.IFF_PROMISC != 0 {
		base.Promisc = 1
	}
	var link Link
	linkType := ""
	for _, attr := range attrs {
		switch attr.Attr.Type {
		case syscall.IFLA_LINKINFO:
			infos, err := nl.ParseRouteAttr(attr.Value)
			if err != nil {
				return nil, err
			}
			for _, info := range infos {
				switch info.Attr.Type {
				case nl.IFLA_INFO_KIND:
					linkType = string(info.Value[:len(info.Value)-1])
					switch linkType {
					case "dummy":
						link = &Dummy{}
					case "ifb":
						link = &Ifb{}
					case "bridge":
						link = &Bridge{}
					case "vlan":
						link = &Vlan{}
					case "veth":
						link = &Veth{}
					case "vxlan":
						link = &Vxlan{}
					case "bond":
						link = &Bond{}
					case "ipvlan":
						link = &IPVlan{}
					case "macvlan":
						link = &Macvlan{}
					case "macvtap":
						link = &Macvtap{}
					case "gretap":
						link = &Gretap{}
					case "ipip":
						link = &Iptun{}
					case "vti":
						link = &Vti{}
					default:
						link = &GenericLink{LinkType: linkType}
					}
				case nl.IFLA_INFO_DATA:
					data, err := nl.ParseRouteAttr(info.Value)
					if err != nil {
						return nil, err
					}
					switch linkType {
					case "vlan":
						parseVlanData(link, data)
					case "vxlan":
						parseVxlanData(link, data)
					case "bond":
						parseBondData(link, data)
					case "ipvlan":
						parseIPVlanData(link, data)
					case "macvlan":
						parseMacvlanData(link, data)
					case "macvtap":
						parseMacvtapData(link, data)
					case "gretap":
						parseGretapData(link, data)
					case "ipip":
						parseIptunData(link, data)
					case "vti":
						parseVtiData(link, data)
					}
				}
			}
		case syscall.IFLA_ADDRESS:
			var nonzero bool
			for _, b := range attr.Value {
				if b != 0 {
					nonzero = true
				}
			}
			if nonzero {
				base.HardwareAddr = attr.Value[:]
			}
		case syscall.IFLA_IFNAME:
			base.Name = string(attr.Value[:len(attr.Value)-1])
		case syscall.IFLA_MTU:
			base.MTU = int(native.Uint32(attr.Value[0:4]))
		case syscall.IFLA_LINK:
			base.ParentIndex = int(native.Uint32(attr.Value[0:4]))
//.........這裏部分代碼省略.........

// linkDeserialize deserializes a raw message received from netlink into
// a link object.
func linkDeserialize(m []byte) (Link, error) {
	msg := nl.DeserializeIfInfomsg(m)

	attrs, err := nl.ParseRouteAttr(m[msg.Len():])
	if err != nil {
		return nil, err
	}

	base := LinkAttrs{Index: int(msg.Index), Flags: linkFlags(msg.Flags)}
	var link Link
	linkType := ""
	for _, attr := range attrs {
		switch attr.Attr.Type {
		case syscall.IFLA_LINKINFO:
			infos, err := nl.ParseRouteAttr(attr.Value)
			if err != nil {
				return nil, err
			}
			for _, info := range infos {
				switch info.Attr.Type {
				case nl.IFLA_INFO_KIND:
					linkType = string(info.Value[:len(info.Value)-1])
					switch linkType {
					case "dummy":
						link = &Dummy{}
					case "bridge":
						link = &Bridge{}
					case "vlan":
						link = &Vlan{}
					case "veth":
						link = &Veth{}
					case "vxlan":
						link = &Vxlan{}
					case "ipvlan":
						link = &IPVlan{}
					case "macvlan":
						link = &Macvlan{}
					default:
						link = &Generic{LinkType: linkType}
					}
				case nl.IFLA_INFO_DATA:
					data, err := nl.ParseRouteAttr(info.Value)
					if err != nil {
						return nil, err
					}
					switch linkType {
					case "vlan":
						parseVlanData(link, data)
					case "vxlan":
						parseVxlanData(link, data)
					case "ipvlan":
						parseIPVlanData(link, data)
					case "macvlan":
						parseMacvlanData(link, data)
					}
				}
			}
		case syscall.IFLA_ADDRESS:
			var nonzero bool
			for _, b := range attr.Value {
				if b != 0 {
					nonzero = true
				}
			}
			if nonzero {
				base.HardwareAddr = attr.Value[:]
			}
		case syscall.IFLA_IFNAME:
			base.Name = string(attr.Value[:len(attr.Value)-1])
		case syscall.IFLA_MTU:
			base.MTU = int(native.Uint32(attr.Value[0:4]))
		case syscall.IFLA_LINK:
			base.ParentIndex = int(native.Uint32(attr.Value[0:4]))
		case syscall.IFLA_MASTER:
			base.MasterIndex = int(native.Uint32(attr.Value[0:4]))
		case syscall.IFLA_TXQLEN:
			base.TxQLen = int(native.Uint32(attr.Value[0:4]))
		}
	}
	// Links that don't have IFLA_INFO_KIND are hardware devices
	if link == nil {
		link = &Device{}
	}
	*link.Attrs() = base

	return link, nil
}

func (u *NetLinkProbe) start() {
	s, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_LINK)
	if err != nil {
		logging.GetLogger().Errorf("Failed to subscribe to netlink RTNLGRP_LINK messages: %s", err.Error())
		return
	}
	u.nlSocket = s
	defer u.nlSocket.Close()

	fd := u.nlSocket.GetFd()

	err = syscall.SetNonblock(fd, true)
	if err != nil {
		logging.GetLogger().Errorf("Failed to set the netlink fd as non-blocking: %s", err.Error())
		return
	}

	epfd, e := syscall.EpollCreate1(0)
	if e != nil {
		logging.GetLogger().Errorf("Failed to create epoll: %s", err.Error())
		return
	}
	defer syscall.Close(epfd)

	u.initialize()

	event := syscall.EpollEvent{Events: syscall.EPOLLIN, Fd: int32(fd)}
	if e = syscall.EpollCtl(epfd, syscall.EPOLL_CTL_ADD, fd, &event); e != nil {
		logging.GetLogger().Errorf("Failed to control epoll: %s", err.Error())
		return
	}

	events := make([]syscall.EpollEvent, maxEpollEvents)

	for u.running.Load() == true {
		n, err := syscall.EpollWait(epfd, events[:], 1000)
		if err != nil {
			errno, ok := err.(syscall.Errno)
			if ok && errno != syscall.EINTR {
				logging.GetLogger().Errorf("Failed to receive from events from netlink: %s", err.Error())
			}
			continue
		}
		if n == 0 {
			continue
		}

		msgs, err := s.Receive()
		if err != nil {
			logging.GetLogger().Errorf("Failed to receive from netlink messages: %s", err.Error())

			time.Sleep(1 * time.Second)
			continue
		}

		for _, msg := range msgs {
			switch msg.Header.Type {
			case syscall.RTM_NEWLINK:
				ifmsg := nl.DeserializeIfInfomsg(msg.Data)
				u.onLinkAdded(int(ifmsg.Index))
			case syscall.RTM_DELLINK:
				ifmsg := nl.DeserializeIfInfomsg(msg.Data)
				u.onLinkDeleted(int(ifmsg.Index))
			}
		}
	}
}