func (e *podEnv) setupNets(nets []activeNet, noDNS bool) error { err := os.MkdirAll(e.netDir(), 0755) if err != nil { return err } i := 0 defer func() { if err != nil { e.teardownNets(nets[:i]) } }() n := activeNet{} // did stage0 already make /etc/rkt-resolv.conf (i.e. --dns passed) resolvPath := filepath.Join(common.Stage1RootfsPath(e.podRoot), "etc/rkt-resolv.conf") _, err = os.Stat(resolvPath) if err != nil && !os.IsNotExist(err) { return errwrap.Wrap(fmt.Errorf("error statting /etc/rkt-resolv.conf"), err) } podHasResolvConf := err == nil for i, n = range nets { if debuglog { stderr.Printf("loading network %v with type %v", n.conf.Name, n.conf.Type) } n.runtime.IfName = fmt.Sprintf(IfNamePattern, i) if n.runtime.ConfPath, err = copyFileToDir(n.runtime.ConfPath, e.netDir()); err != nil { return errwrap.Wrap(fmt.Errorf("error copying %q to %q", n.runtime.ConfPath, e.netDir()), err) } // Actually shell out to the plugin err = e.netPluginAdd(&n, e.podNS.Path()) if err != nil { return errwrap.Wrap(fmt.Errorf("error adding network %q", n.conf.Name), err) } // Generate rkt-resolv.conf if it's not already there. // The first network plugin that supplies a non-empty // DNS response will win, unless noDNS is true (--dns passed to rkt run) if !common.IsDNSZero(&n.runtime.DNS) && !noDNS { if !podHasResolvConf { err := ioutil.WriteFile( resolvPath, []byte(common.MakeResolvConf(n.runtime.DNS, "Generated by rkt from network "+n.conf.Name)), 0644) if err != nil { return errwrap.Wrap(fmt.Errorf("error creating resolv.conf"), err) } podHasResolvConf = true } else { stderr.Printf("Warning: network %v plugin specified DNS configuration, but DNS already supplied", n.conf.Name) } } } return nil }
// writeResolvConf will generate <stage1>/etc/rkt-resolv.conf if needed func writeResolvConf(cfg *RunConfig, rootfs string) { if cfg.DNSConfMode.Resolv != "stage0" { return } if err := os.Mkdir(filepath.Join(rootfs, "etc"), common.DefaultRegularDirPerm); err != nil { if !os.IsExist(err) { log.Fatalf("error creating dir %q: %v\n", "/etc", err) } } resolvPath := filepath.Join(rootfs, "etc/rkt-resolv.conf") f, err := os.Create(resolvPath) if err != nil { log.Fatalf("error writing etc/rkt-resolv.conf: %v\n", err) } defer f.Close() _, err = f.WriteString(common.MakeResolvConf(cfg.DNSConfig, "Generated by rkt run")) if err != nil { log.Fatalf("error writing etc/rkt-resolv.conf: %v\n", err) } }
// kvmSetup prepare new Networking to be used in kvm environment based on tuntap pair interfaces // to allow communication with virtual machine created by lkvm tool func kvmSetup(podRoot string, podID types.UUID, fps []ForwardedPort, netList common.NetList, localConfig string, noDNS bool) (*Networking, error) { network := Networking{ podEnv: podEnv{ podRoot: podRoot, podID: podID, netsLoadList: netList, localConfig: localConfig, }, } var e error // If there's a network set as default in CNI configuration defaultGatewaySet := false _, defaultNet, err := net.ParseCIDR("0.0.0.0/0") if err != nil { return nil, errwrap.Wrap(errors.New("error when parsing net address"), err) } network.nets, e = network.loadNets() if e != nil { return nil, errwrap.Wrap(errors.New("error loading network definitions"), e) } // did stage0 already make /etc/rkt-resolv.conf (i.e. --dns passed) resolvPath := filepath.Join(common.Stage1RootfsPath(podRoot), "etc/rkt-resolv.conf") _, err = os.Stat(resolvPath) if err != nil && !os.IsNotExist(err) { return nil, errwrap.Wrap(fmt.Errorf("error statting /etc/rkt-resolv.conf"), err) } podHasResolvConf := err == nil for i, n := range network.nets { if n.conf.Type == "flannel" { if err := kvmTransformFlannelNetwork(&n); err != nil { return nil, errwrap.Wrap(errors.New("cannot transform flannel network into basic network"), err) } } switch n.conf.Type { case "ptp": link, err := setupTapDevice(podID) if err != nil { return nil, err } ifName := link.Attrs().Name n.runtime.IfName = ifName err = kvmSetupNetAddressing(&network, n, ifName) if err != nil { return nil, err } // add address to host tap device err = ensureHasAddr( link, &net.IPNet{ IP: n.runtime.IP4.Gateway, Mask: net.IPMask(n.runtime.Mask), }, ) if err != nil { return nil, errwrap.Wrap(fmt.Errorf("cannot add address to host tap device %q", ifName), err) } if err := removeAllRoutesOnLink(link); err != nil { return nil, errwrap.Wrap(fmt.Errorf("cannot remove route on host tap device %q", ifName), err) } if err := addRoute(link, n.runtime.IP); err != nil { return nil, errwrap.Wrap(errors.New("cannot add on host direct route to pod"), err) } case "bridge": config := BridgeNetConf{ NetConf: NetConf{ MTU: defaultMTU, }, BrName: defaultBrName, } if err := json.Unmarshal(n.confBytes, &config); err != nil { return nil, errwrap.Wrap(fmt.Errorf("error parsing %q result", n.conf.Name), err) } br, err := ensureBridgeIsUp(config.BrName, config.MTU) if err != nil { return nil, errwrap.Wrap(errors.New("error in time of bridge setup"), err) } link, err := setupTapDevice(podID) if err != nil { return nil, errwrap.Wrap(errors.New("can not setup tap device"), err) } err = netlink.LinkSetMaster(link, br) if err != nil { rErr := tuntap.RemovePersistentIface(n.runtime.IfName, tuntap.Tap) if rErr != nil { stderr.PrintE("warning: could not cleanup tap interface", rErr) } return nil, errwrap.Wrap(errors.New("can not add tap interface to bridge"), err) } ifName := link.Attrs().Name n.runtime.IfName = ifName err = kvmSetupNetAddressing(&network, n, ifName) if err != nil { return nil, err } if n.conf.IsDefaultGateway { n.runtime.IP4.Routes = append( n.runtime.IP4.Routes, cnitypes.Route{Dst: *defaultNet, GW: n.runtime.IP4.Gateway}, ) defaultGatewaySet = true config.IsGw = true } if config.IsGw { err = ensureHasAddr( br, &net.IPNet{ IP: n.runtime.IP4.Gateway, Mask: net.IPMask(n.runtime.Mask), }, ) if err != nil { return nil, errwrap.Wrap(fmt.Errorf("cannot add address to host bridge device %q", br.Name), err) } } case "macvlan": config := MacVTapNetConf{} if err := json.Unmarshal(n.confBytes, &config); err != nil { return nil, errwrap.Wrap(fmt.Errorf("error parsing %q result", n.conf.Name), err) } link, err := setupMacVTapDevice(podID, config, i) if err != nil { return nil, err } ifName := link.Attrs().Name n.runtime.IfName = ifName err = kvmSetupNetAddressing(&network, n, ifName) if err != nil { return nil, err } default: return nil, fmt.Errorf("network %q have unsupported type: %q", n.conf.Name, n.conf.Type) } // Check if there's any other network set as default gateway if defaultGatewaySet { for _, route := range n.runtime.IP4.Routes { if (defaultNet.String() == route.Dst.String()) && !n.conf.IsDefaultGateway { return nil, fmt.Errorf("flannel config enables default gateway and IPAM sets default gateway via %q", n.runtime.IP4.Gateway) } } } // Generate rkt-resolv.conf if it's not already there. // The first network plugin that supplies a non-empty // DNS response will win, unless noDNS is true (--dns passed to rkt run) if !common.IsDNSZero(&n.runtime.DNS) && !noDNS { if !podHasResolvConf { err := ioutil.WriteFile( resolvPath, []byte(common.MakeResolvConf(n.runtime.DNS, "Generated by rkt from network "+n.conf.Name)), 0644) if err != nil { return nil, errwrap.Wrap(fmt.Errorf("error creating resolv.conf"), err) } podHasResolvConf = true } else { stderr.Printf("Warning: network %v plugin specified DNS configuration, but DNS already supplied", n.conf.Name) } } if n.conf.IPMasq { chain := cniutils.FormatChainName(n.conf.Name, podID.String()) comment := cniutils.FormatComment(n.conf.Name, podID.String()) if err := ip.SetupIPMasq(&net.IPNet{ IP: n.runtime.IP, Mask: net.IPMask(n.runtime.Mask), }, chain, comment); err != nil { return nil, err } } network.nets[i] = n } podIP, err := network.GetForwardableNetPodIP() if err != nil { return nil, err } if err := network.forwardPorts(fps, podIP); err != nil { return nil, err } return &network, nil }