Golang nl.Subscribe函数代码示例

func (n *network) initSandbox() error {
	n.Lock()
	n.initEpoch++
	n.Unlock()

	sbox, err := osl.NewSandbox(
		osl.GenerateKey(fmt.Sprintf("%d-", n.initEpoch)+n.id), true)
	if err != nil {
		return fmt.Errorf("could not create network sandbox: %v", err)
	}

	n.setSandbox(sbox)

	n.driver.peerDbUpdateSandbox(n.id)

	var nlSock *nl.NetlinkSocket
	sbox.InvokeFunc(func() {
		nlSock, err = nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_NEIGH)
		if err != nil {
			err = fmt.Errorf("failed to subscribe to neighbor group netlink messages")
		}
	})

	go n.watchMiss(nlSock)
	return nil
}

// LinkSubscribe takes a chan down which notifications will be sent
// when links change.  Close the 'done' chan to stop subscription.
func LinkSubscribe(ch chan<- LinkUpdate, done <-chan struct{}) error {
	s, err := nl.Subscribe(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, Link: link}
			}
		}
	}()

	return nil
}

// RouteSubscribe takes a chan down which notifications will be sent
// when routes are added or deleted. Close the 'done' chan to stop subscription.
func RouteSubscribe(ch chan<- RouteUpdate, done <-chan struct{}) error {
	s, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_IPV4_ROUTE, syscall.RTNLGRP_IPV6_ROUTE)
	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 {
				route, err := deserializeRoute(m.Data)
				if err != nil {
					return
				}
				ch <- RouteUpdate{Type: m.Header.Type, Route: route}
			}
		}
	}()

	return nil
}

func (n *network) initSandbox() error {
	n.Lock()
	n.initEpoch++
	n.Unlock()

	sbox, err := osl.NewSandbox(
		osl.GenerateKey(fmt.Sprintf("%d-", n.initEpoch)+n.id), true)
	if err != nil {
		return fmt.Errorf("could not create network sandbox: %v", err)
	}

	// Add a bridge inside the namespace
	if err := sbox.AddInterface("bridge1", "br",
		sbox.InterfaceOptions().Address(bridgeIP),
		sbox.InterfaceOptions().Bridge(true)); err != nil {
		return fmt.Errorf("could not create bridge inside the network sandbox: %v", err)
	}

	n.setSandbox(sbox)

	var nlSock *nl.NetlinkSocket
	sbox.InvokeFunc(func() {
		nlSock, err = nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_NEIGH)
		if err != nil {
			err = fmt.Errorf("failed to subscribe to neighbor group netlink messages")
		}
	})

	go n.watchMiss(nlSock)
	return n.initVxlan()
}

func (n *network) initSandbox(restore bool) error {
	n.Lock()
	n.initEpoch++
	n.Unlock()

	networkOnce.Do(networkOnceInit)

	if !restore {
		if hostMode {
			if err := addNetworkChain(n.id[:12]); err != nil {
				return err
			}
		}

		// If there are any stale sandboxes related to this network
		// from previous daemon life clean it up here
		n.cleanupStaleSandboxes()
	}

	// In the restore case network sandbox already exist; but we don't know
	// what epoch number it was created with. It has to be retrieved by
	// searching the net namespaces.
	key := ""
	if restore {
		key = osl.GenerateKey("-" + n.id)
	} else {
		key = osl.GenerateKey(fmt.Sprintf("%d-", n.initEpoch) + n.id)
	}

	sbox, err := osl.NewSandbox(key, !hostMode, restore)
	if err != nil {
		return fmt.Errorf("could not get network sandbox (oper %t): %v", restore, err)
	}

	n.setSandbox(sbox)

	if !restore {
		n.driver.peerDbUpdateSandbox(n.id)
	}

	var nlSock *nl.NetlinkSocket
	sbox.InvokeFunc(func() {
		nlSock, err = nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_NEIGH)
		if err != nil {
			err = fmt.Errorf("failed to subscribe to neighbor group netlink messages")
		}
	})

	if nlSock != nil {
		go n.watchMiss(nlSock)
	}

	return nil
}

// Wait for an interface to come up.
func EnsureInterface(ifaceName string) (*net.Interface, error) {
	s, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_LINK)
	if err != nil {
		return nil, err
	}
	defer s.Close()
	iface, err := ensureInterface(s, ifaceName)
	if err != nil {
		return nil, err
	}
	return iface, err
}

func (n *network) initSandbox() error {
	n.Lock()
	n.initEpoch++
	n.Unlock()

	sbox, err := sandbox.NewSandbox(
		sandbox.GenerateKey(fmt.Sprintf("%d-", n.initEpoch)+string(n.id)), true)
	if err != nil {
		return fmt.Errorf("could not create network sandbox: %v", err)
	}

	// Add a bridge inside the namespace
	if err := sbox.AddInterface("bridge1", "br",
		sbox.InterfaceOptions().Address(bridgeIP),
		sbox.InterfaceOptions().Bridge(true)); err != nil {
		return fmt.Errorf("could not create bridge inside the network sandbox: %v", err)
	}

	vxlanName, err := createVxlan(n.vxlanID())
	if err != nil {
		return err
	}

	if err := sbox.AddInterface(vxlanName, "vxlan",
		sbox.InterfaceOptions().Master("bridge1")); err != nil {
		return fmt.Errorf("could not add vxlan interface inside the network sandbox: %v",
			err)
	}

	n.vxlanName = vxlanName

	n.setSandbox(sbox)

	n.driver.peerDbUpdateSandbox(n.id)

	var nlSock *nl.NetlinkSocket
	sbox.InvokeFunc(func() {
		nlSock, err = nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_NEIGH)
		if err != nil {
			err = fmt.Errorf("failed to subscribe to neighbor group netlink messages")
		}
	})

	go n.watchMiss(nlSock)

	return nil
}

// Wait for an interface to come up and have a route added to the multicast subnet.
// This matches the behaviour in 'weave attach', which is the only context in which
// we expect this to be called.  If you change one, change the other to match.
func EnsureInterfaceAndMcastRoute(ifaceName string) (*net.Interface, error) {
	s, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_LINK, syscall.RTNLGRP_IPV4_ROUTE)
	if err != nil {
		return nil, err
	}
	defer s.Close()
	iface, err := ensureInterface(s, ifaceName)
	if err != nil {
		return nil, err
	}
	dest := net.IPv4(224, 0, 0, 0)
	if CheckRouteExists(ifaceName, dest) {
		return iface, err
	}
	netlinkReceiveUntil(s, matchRoute(ifaceName, dest))
	return iface, err
}

func (n *network) initSandbox() error {
	n.Lock()
	n.initEpoch++
	n.Unlock()

	networkOnce.Do(networkOnceInit)

	if hostMode {
		if err := addNetworkChain(n.id[:12]); err != nil {
			return err
		}
	}

	// If there are any stale sandboxes related to this network
	// from previous daemon life clean it up here
	n.cleanupStaleSandboxes()

	sbox, err := osl.NewSandbox(
		osl.GenerateKey(fmt.Sprintf("%d-", n.initEpoch)+n.id), !hostMode)
	if err != nil {
		return fmt.Errorf("could not create network sandbox: %v", err)
	}

	n.setSandbox(sbox)

	n.driver.peerDbUpdateSandbox(n.id)

	var nlSock *nl.NetlinkSocket
	sbox.InvokeFunc(func() {
		nlSock, err = nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_NEIGH)
		if err != nil {
			err = fmt.Errorf("failed to subscribe to neighbor group netlink messages")
		}
	})

	if nlSock != nil {
		go n.watchMiss(nlSock)
	}

	return nil
}

func (dev *vxlanDevice) MonitorMisses(misses chan *netlink.Neigh) {
	nlsock, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_NEIGH)
	if err != nil {
		log.Error("Failed to subscribe to netlink RTNLGRP_NEIGH messages")
		return
	}

	for {
		msgs, err := nlsock.Receive()
		if err != nil {
			log.Errorf("Failed to receive from netlink: %v ", err)

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

		for _, msg := range msgs {
			dev.processNeighMsg(msg, misses)
		}
	}
}

// AddrSubscribe takes a chan down which notifications will be sent
// when addresses change.  Close the 'done' chan to stop subscription.
func AddrSubscribe(ch chan<- AddrUpdate, done <-chan struct{}) error {
	s, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_IPV4_IFADDR, syscall.RTNLGRP_IPV6_IFADDR)
	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 {
				log.Printf("netlink.AddrSubscribe: Receive() error: %v", err)
				return
			}
			for _, m := range msgs {
				msgType := m.Header.Type
				if msgType != syscall.RTM_NEWADDR && msgType != syscall.RTM_DELADDR {
					log.Printf("netlink.AddrSubscribe: bad message type: %d", msgType)
					continue
				}

				addr, _, ifindex, err := parseAddr(m.Data)
				if err != nil {
					log.Printf("netlink.AddrSubscribe: could not parse address: %v", err)
					continue
				}

				ch <- AddrUpdate{LinkAddress: *addr.IPNet, LinkIndex: ifindex, NewAddr: msgType == syscall.RTM_NEWADDR}
			}
		}
	}()

	return nil
}

func (*nl) Subscribe(protocol int, groups ...uint) (NLSocket, error) {
	return vish_nl.Subscribe(protocol, groups...)
}

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))
			}
		}
	}
}

func (u *NetLinkProbe) start(nsPath string) {
	var context *common.NetNSContext
	var err error

	// Enter the network namespace if necessary
	if nsPath != "" {
		context, err = common.NewNetNsContext(nsPath)
		if err != nil {
			logging.GetLogger().Errorf("Failed to switch namespace: %s", err.Error())
			return
		}
	}

	// Both NewHandle and Subscribe need to done in the network namespace.
	h, err := netlink.NewHandle(syscall.NETLINK_ROUTE)
	if err != nil {
		logging.GetLogger().Errorf("Failed to create netlink handle: %s", err.Error())
		context.Close()
		return
	}
	defer h.Delete()

	s, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_LINK, syscall.RTNLGRP_IPV4_IFADDR, syscall.RTNLGRP_IPV6_IFADDR)
	if err != nil {
		logging.GetLogger().Errorf("Failed to subscribe to netlink messages: %s", err.Error())
		context.Close()
		return
	}
	defer s.Close()

	u.ethtool, err = ethtool.NewEthtool()
	if err != nil {
		logging.GetLogger().Errorf("Failed to create ethtool object: %s", err.Error())
		context.Close()
		return
	}
	defer u.ethtool.Close()

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

	// Leave the network namespace
	context.Close()

	u.wg.Add(1)
	defer u.wg.Done()

	atomic.StoreInt64(&u.state, common.RunningState)
	defer atomic.StoreInt64(&u.state, common.StoppedState)

	u.netlink = h
	u.initialize()

	fd := s.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
	}

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

	for atomic.LoadInt64(&u.state) == common.RunningState {
		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 {
			if errno, ok := err.(syscall.Errno); !ok || !errno.Temporary() {
				logging.GetLogger().Errorf("Failed to receive from netlink messages: %s", err.Error())
				return
			}
			time.Sleep(1 * time.Second)
			continue
		}

		for _, msg := range msgs {
			switch msg.Header.Type {
			case syscall.RTM_NEWLINK:
				link, err := netlink.LinkDeserialize(msg.Data)
				if err != nil {
					logging.GetLogger().Warningf("Failed to deserialize netlink message: %s", err.Error())
//.........这里部分代码省略.........