Golang iptables.NewChain函數代碼示例

func newPortMapper(config *DaemonConfig) (*PortMapper, error) {
	// We can always try removing the iptables
	if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
		return nil, err
	}
	var chain *iptables.Chain
	if config.EnableIptables {
		var err error
		chain, err = iptables.NewChain("DOCKER", config.BridgeIface)
		if err != nil {
			return nil, fmt.Errorf("Failed to create DOCKER chain: %s", err)
		}
	}

	mapper := &PortMapper{
		tcpMapping:       make(map[string]*net.TCPAddr),
		tcpProxies:       make(map[string]proxy.Proxy),
		udpMapping:       make(map[string]*net.UDPAddr),
		udpProxies:       make(map[string]proxy.Proxy),
		iptables:         chain,
		defaultIp:        config.DefaultIp,
		proxyFactoryFunc: proxy.NewProxy,
	}
	return mapper, nil
}

func InitDriver(job *engine.Job) engine.Status {
	var (
		network        *net.IPNet
		enableIPTables = job.GetenvBool("EnableIptables")
		icc            = job.GetenvBool("InterContainerCommunication")
		ipForward      = job.GetenvBool("EnableIpForward")
		bridgeIP       = job.Getenv("BridgeIP")
	)

	if defaultIP := job.Getenv("DefaultBindingIP"); defaultIP != "" {
		defaultBindingIP = net.ParseIP(defaultIP)
	}

	bridgeIface = job.Getenv("BridgeIface")
	usingDefaultBridge := false
	if bridgeIface == "" {
		usingDefaultBridge = true
		bridgeIface = DefaultNetworkBridge
	}

	addr, err := networkdriver.GetIfaceAddr(bridgeIface)
	if err != nil {
		// If we're not using the default bridge, fail without trying to create it
		if !usingDefaultBridge {
			job.Logf("bridge not found: %s", bridgeIface)
			return job.Error(err)
		}
		// If the iface is not found, try to create it
		job.Logf("creating new bridge for %s", bridgeIface)
		if err := createBridge(bridgeIP); err != nil {
			return job.Error(err)
		}

		job.Logf("getting iface addr")
		addr, err = networkdriver.GetIfaceAddr(bridgeIface)
		if err != nil {
			return job.Error(err)
		}
		network = addr.(*net.IPNet)
	} else {
		network = addr.(*net.IPNet)
		// validate that the bridge ip matches the ip specified by BridgeIP
		if bridgeIP != "" {
			bip, _, err := net.ParseCIDR(bridgeIP)
			if err != nil {
				return job.Error(err)
			}
			if !network.IP.Equal(bip) {
				return job.Errorf("bridge ip (%s) does not match existing bridge configuration %s", network.IP, bip)
			}
		}
	}

	// Configure iptables for link support
	if enableIPTables {
		if err := setupIPTables(addr, icc); err != nil {
			return job.Error(err)
		}
	}

	if ipForward {
		// Enable IPv4 forwarding
		if err := ioutil.WriteFile("/proc/sys/net/ipv4/ip_forward", []byte{'1', '\n'}, 0644); err != nil {
			job.Logf("WARNING: unable to enable IPv4 forwarding: %s\n", err)
		}
	}

	// We can always try removing the iptables
	if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
		return job.Error(err)
	}

	if enableIPTables {
		chain, err := iptables.NewChain("DOCKER", bridgeIface)
		if err != nil {
			return job.Error(err)
		}
		portmapper.SetIptablesChain(chain)
	}

	bridgeNetwork = network

	// https://github.com/dotcloud/docker/issues/2768
	job.Eng.Hack_SetGlobalVar("httpapi.bridgeIP", bridgeNetwork.IP)

	for name, f := range map[string]engine.Handler{
		"allocate_interface": Allocate,
		"release_interface":  Release,
		"allocate_port":      AllocatePort,
		"link":               LinkContainers,
	} {
		if err := job.Eng.Register(name, f); err != nil {
			return job.Error(err)
		}
	}
	return engine.StatusOK
}

//.........這裏部分代碼省略.........
		addr, err = getIfaceAddr(config.BridgeIface)
		if err != nil {
			return nil, err
		}
		network = addr.(*net.IPNet)
	} else {
		network = addr.(*net.IPNet)
	}

	// Configure iptables for link support
	if config.EnableIptables {

		// Enable NAT
		natArgs := []string{"POSTROUTING", "-t", "nat", "-s", addr.String(), "!", "-d", addr.String(), "-j", "MASQUERADE"}

		if !iptables.Exists(natArgs...) {
			if output, err := iptables.Raw(append([]string{"-A"}, natArgs...)...); err != nil {
				return nil, fmt.Errorf("Unable to enable network bridge NAT: %s", err)
			} else if len(output) != 0 {
				return nil, fmt.Errorf("Error iptables postrouting: %s", output)
			}
		}

		args := []string{"FORWARD", "-i", config.BridgeIface, "-o", config.BridgeIface, "-j"}
		acceptArgs := append(args, "ACCEPT")
		dropArgs := append(args, "DROP")

		if !config.InterContainerCommunication {
			iptables.Raw(append([]string{"-D"}, acceptArgs...)...)
			if !iptables.Exists(dropArgs...) {
				utils.Debugf("Disable inter-container communication")
				if output, err := iptables.Raw(append([]string{"-I"}, dropArgs...)...); err != nil {
					return nil, fmt.Errorf("Unable to prevent intercontainer communication: %s", err)
				} else if len(output) != 0 {
					return nil, fmt.Errorf("Error disabling intercontainer communication: %s", output)
				}
			}
		} else {
			iptables.Raw(append([]string{"-D"}, dropArgs...)...)
			if !iptables.Exists(acceptArgs...) {
				utils.Debugf("Enable inter-container communication")
				if output, err := iptables.Raw(append([]string{"-I"}, acceptArgs...)...); err != nil {
					return nil, fmt.Errorf("Unable to allow intercontainer communication: %s", err)
				} else if len(output) != 0 {
					return nil, fmt.Errorf("Error enabling intercontainer communication: %s", output)
				}
			}
		}

		// Accept all non-intercontainer outgoing packets
		outgoingArgs := []string{"FORWARD", "-i", config.BridgeIface, "!", "-o", config.BridgeIface, "-j", "ACCEPT"}

		if !iptables.Exists(outgoingArgs...) {
			if output, err := iptables.Raw(append([]string{"-I"}, outgoingArgs...)...); err != nil {
				return nil, fmt.Errorf("Unable to allow outgoing packets: %s", err)
			} else if len(output) != 0 {
				return nil, fmt.Errorf("Error iptables allow outgoing: %s", output)
			}
		}

		// Accept incoming packets for existing connections
		existingArgs := []string{"FORWARD", "-o", config.BridgeIface, "-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED", "-j", "ACCEPT"}

		if !iptables.Exists(existingArgs...) {
			if output, err := iptables.Raw(append([]string{"-I"}, existingArgs...)...); err != nil {
				return nil, fmt.Errorf("Unable to allow incoming packets: %s", err)
			} else if len(output) != 0 {
				return nil, fmt.Errorf("Error iptables allow incoming: %s", output)
			}
		}

	}

	if config.EnableIpForward {
		// Enable IPv4 forwarding
		if err := ioutil.WriteFile("/proc/sys/net/ipv4/ip_forward", []byte{'1', '\n'}, 0644); err != nil {
			log.Printf("WARNING: unable to enable IPv4 forwarding: %s\n", err)
		}
	}

	// We can always try removing the iptables
	if err := iptables.RemoveExistingChain("DOCKER"); err != nil {
		return nil, err
	}

	if config.EnableIptables {
		chain, err := iptables.NewChain("DOCKER", config.BridgeIface)
		if err != nil {
			return nil, err
		}
		portmapper.SetIptablesChain(chain)
	}

	manager := &NetworkManager{
		bridgeIface:      config.BridgeIface,
		bridgeNetwork:    network,
		defaultBindingIP: config.DefaultIp,
	}
	return manager, nil
}