package network import ( "encoding/json" "fmt" "io/ioutil" "os" "path/filepath" "strconv" "github.com/containernetworking/cni/pkg/version" "github.com/containers/common/pkg/config" "github.com/containers/podman/v3/pkg/domain/entities" "github.com/containers/podman/v3/pkg/util" "github.com/pkg/errors" "github.com/sirupsen/logrus" ) // Create the CNI network func Create(name string, options entities.NetworkCreateOptions, runtimeConfig *config.Config) (*entities.NetworkCreateReport, error) { var fileName string if err := isSupportedDriver(options.Driver); err != nil { return nil, err } // Acquire a lock for CNI l, err := acquireCNILock(runtimeConfig) if err != nil { return nil, err } defer l.releaseCNILock() if len(options.MacVLAN) > 0 || options.Driver == MacVLANNetworkDriver { fileName, err = createMacVLAN(name, options, runtimeConfig) } else { fileName, err = createBridge(name, options, runtimeConfig) } if err != nil { return nil, err } return &entities.NetworkCreateReport{Filename: fileName}, nil } // validateBridgeOptions validate the bridge networking options func validateBridgeOptions(options entities.NetworkCreateOptions) error { subnet := &options.Subnet ipRange := &options.Range gateway := options.Gateway // if IPv6 is set an IPv6 subnet MUST be specified if options.IPv6 && ((subnet.IP == nil) || (subnet.IP != nil && !IsIPv6(subnet.IP))) { return errors.Errorf("ipv6 option requires an IPv6 --subnet to be provided") } // range and gateway depend on subnet if subnet.IP == nil && (ipRange.IP != nil || gateway != nil) { return errors.Errorf("every ip-range or gateway must have a corresponding subnet") } // if a range is given, we need to ensure it is "in" the network range. if ipRange.IP != nil { firstIP, err := FirstIPInSubnet(ipRange) if err != nil { return errors.Wrapf(err, "failed to get first IP address from ip-range") } lastIP, err := LastIPInSubnet(ipRange) if err != nil { return errors.Wrapf(err, "failed to get last IP address from ip-range") } if !subnet.Contains(firstIP) || !subnet.Contains(lastIP) { return errors.Errorf("the ip range %s does not fall within the subnet range %s", ipRange.String(), subnet.String()) } } // if network is provided and if gateway is provided, make sure it is "in" network if gateway != nil && !subnet.Contains(gateway) { return errors.Errorf("gateway %s is not in valid for subnet %s", gateway.String(), subnet.String()) } return nil } // parseMTU parses the mtu option func parseMTU(mtu string) (int, error) { if mtu == "" { return 0, nil // default } m, err := strconv.Atoi(mtu) if err != nil { return 0, err } if m < 0 { return 0, errors.Errorf("the value %d for mtu is less than zero", m) } return m, nil } // parseVlan parses the vlan option func parseVlan(vlan string) (int, error) { if vlan == "" { return 0, nil // default } return strconv.Atoi(vlan) } // createBridge creates a CNI network func createBridge(name string, options entities.NetworkCreateOptions, runtimeConfig *config.Config) (string, error) { var ( ipamRanges [][]IPAMLocalHostRangeConf err error routes []IPAMRoute ) isGateway := true ipMasq := true // validate options if err := validateBridgeOptions(options); err != nil { return "", err } // For compatibility with the docker implementation: // if IPv6 is enabled (it really means dual-stack) then an IPv6 subnet has to be provided, and one free network is allocated for IPv4 // if IPv6 is not specified the subnet may be specified and can be either IPv4 or IPv6 (podman, unlike docker, allows IPv6 only networks) // If not subnet is specified an IPv4 subnet will be allocated subnet := &options.Subnet ipRange := &options.Range gateway := options.Gateway if subnet.IP != nil { // if network is provided, does it conflict with existing CNI or live networks err = ValidateUserNetworkIsAvailable(runtimeConfig, subnet) if err != nil { return "", err } // obtain CNI subnet default route defaultRoute, err := NewIPAMDefaultRoute(IsIPv6(subnet.IP)) if err != nil { return "", err } routes = append(routes, defaultRoute) // obtain CNI range ipamRange, err := NewIPAMLocalHostRange(subnet, ipRange, gateway) if err != nil { return "", err } ipamRanges = append(ipamRanges, ipamRange) } // if no network is provided or IPv6 flag used, figure out the IPv4 network if options.IPv6 || len(routes) == 0 { subnetV4, err := GetFreeNetwork(runtimeConfig) if err != nil { return "", err } // obtain IPv4 default route defaultRoute, err := NewIPAMDefaultRoute(false) if err != nil { return "", err } routes = append(routes, defaultRoute) // the CNI bridge plugin does not need to set // the range or gateway options explicitly ipamRange, err := NewIPAMLocalHostRange(subnetV4, nil, nil) if err != nil { return "", err } ipamRanges = append(ipamRanges, ipamRange) } // create CNI config ipamConfig, err := NewIPAMHostLocalConf(routes, ipamRanges) if err != nil { return "", err } if options.Internal { isGateway = false ipMasq = false } var mtu int var vlan int for k, v := range options.Options { var err error switch k { case "mtu": mtu, err = parseMTU(v) if err != nil { return "", err } case "vlan": vlan, err = parseVlan(v) if err != nil { return "", err } default: return "", errors.Errorf("unsupported option %s", k) } } // obtain host bridge name bridgeDeviceName, err := GetFreeDeviceName(runtimeConfig) if err != nil { return "", err } if len(name) > 0 { netNames, err := GetNetworkNamesFromFileSystem(runtimeConfig) if err != nil { return "", err } if util.StringInSlice(name, netNames) { return "", errors.Errorf("the network name %s is already used", name) } } else { // If no name is given, we give the name of the bridge device name = bridgeDeviceName } // create CNI plugin configuration ncList := NewNcList(name, version.Current(), options.Labels) var plugins []CNIPlugins // TODO need to iron out the role of isDefaultGW and IPMasq bridge := NewHostLocalBridge(bridgeDeviceName, isGateway, false, ipMasq, mtu, vlan, ipamConfig) plugins = append(plugins, bridge) plugins = append(plugins, NewPortMapPlugin()) plugins = append(plugins, NewFirewallPlugin()) plugins = append(plugins, NewTuningPlugin()) // if we find the dnsname plugin we add configuration for it if HasDNSNamePlugin(runtimeConfig.Network.CNIPluginDirs) && !options.DisableDNS { if options.Internal { logrus.Warnf("dnsname and --internal networks are incompatible. dnsname plugin not configured for network %s", name) } else { // Note: in the future we might like to allow for dynamic domain names plugins = append(plugins, NewDNSNamePlugin(DefaultPodmanDomainName)) } } // Add the podman-machine CNI plugin if we are in a machine if runtimeConfig.MachineEnabled() { // check if we are in a machine vm plugins = append(plugins, NewPodmanMachinePlugin()) } ncList["plugins"] = plugins b, err := json.MarshalIndent(ncList, "", " ") if err != nil { return "", err } if err := os.MkdirAll(GetCNIConfDir(runtimeConfig), 0755); err != nil { return "", err } cniPathName := filepath.Join(GetCNIConfDir(runtimeConfig), fmt.Sprintf("%s.conflist", name)) err = ioutil.WriteFile(cniPathName, b, 0644) return cniPathName, err } func createMacVLAN(name string, options entities.NetworkCreateOptions, runtimeConfig *config.Config) (string, error) { var ( mtu int plugins []CNIPlugins ) liveNetNames, err := GetLiveNetworkNames() if err != nil { return "", err } // The parent can be defined with --macvlan or as an option (-o parent:device) parentNetworkDevice := options.MacVLAN if len(parentNetworkDevice) < 1 { if parent, ok := options.Options["parent"]; ok { parentNetworkDevice = parent } } // Make sure the host-device exists if provided if len(parentNetworkDevice) > 0 && !util.StringInSlice(parentNetworkDevice, liveNetNames) { return "", errors.Errorf("failed to find network interface %q", parentNetworkDevice) } if len(name) > 0 { netNames, err := GetNetworkNamesFromFileSystem(runtimeConfig) if err != nil { return "", err } if util.StringInSlice(name, netNames) { return "", errors.Errorf("the network name %s is already used", name) } } else { name, err = GetFreeDeviceName(runtimeConfig) if err != nil { return "", err } } ncList := NewNcList(name, version.Current(), options.Labels) if val, ok := options.Options["mtu"]; ok { intVal, err := strconv.Atoi(val) if err != nil { return "", err } if intVal > 0 { mtu = intVal } } macvlan, err := NewMacVLANPlugin(parentNetworkDevice, options.Gateway, &options.Range, &options.Subnet, mtu) if err != nil { return "", err } plugins = append(plugins, macvlan) ncList["plugins"] = plugins b, err := json.MarshalIndent(ncList, "", " ") if err != nil { return "", err } cniPathName := filepath.Join(GetCNIConfDir(runtimeConfig), fmt.Sprintf("%s.conflist", name)) err = ioutil.WriteFile(cniPathName, b, 0644) return cniPathName, err }