func cmdAdd(args *skel.CmdArgs) error { n, err := loadNetConf(args.StdinData) if err != nil { return err } br, err := setupBridge(n) if err != nil { return err } if err = setupVeth(args.Netns, br, args.IfName, n.MTU); err != nil { return err } // run the IPAM plugin and get back the config to apply result, err := ipam.ExecAdd(n.IPAM.Type, args.StdinData) if err != nil { return err } if result.IP4 == nil { return errors.New("IPAM plugin returned missing IPv4 config") } if result.IP4.Gateway == nil && n.IsGW { result.IP4.Gateway = calcGatewayIP(&result.IP4.IP) } err = ns.WithNetNSPath(args.Netns, false, func(hostNS *os.File) error { return ipam.ConfigureIface(args.IfName, result) }) if err != nil { return err } if n.IsGW { gwn := &net.IPNet{ IP: result.IP4.Gateway, Mask: result.IP4.IP.Mask, } if err = ensureBridgeAddr(br, gwn); err != nil { return err } if err := ip.EnableIP4Forward(); err != nil { return fmt.Errorf("failed to enable forwarding: %v", err) } } if n.IPMasq { chain := "CNI-" + n.Name if err = ip.SetupIPMasq(ip.Network(&result.IP4.IP), chain); err != nil { return err } } return result.Print() }
func cmdAdd(args *skel.CmdArgs) error { n, err := loadConf(args.StdinData) if err != nil { return err } netns, err := os.Open(args.Netns) if err != nil { return fmt.Errorf("failed to open netns %q: %v", netns, err) } defer netns.Close() if err = createIpvlan(n, args.IfName, netns); err != nil { return err } // run the IPAM plugin and get back the config to apply result, err := ipam.ExecAdd(n.IPAM.Type, args.StdinData) if err != nil { return err } if result.IP4 == nil { return errors.New("IPAM plugin returned missing IPv4 config") } err = ns.WithNetNS(netns, false, func(_ *os.File) error { return ipam.ConfigureIface(args.IfName, result) }) if err != nil { return err } return result.Print() }
func setupContainerVeth(netns, ifName string, mtu int, pr *types.Result) (string, error) { // The IPAM result will be something like IP=192.168.3.5/24, GW=192.168.3.1. // What we want is really a point-to-point link but veth does not support IFF_POINTOPONT. // Next best thing would be to let it ARP but set interface to 192.168.3.5/32 and // add a route like "192.168.3.0/24 via 192.168.3.1 dev $ifName". // Unfortunately that won't work as the GW will be outside the interface's subnet. // Our solution is to configure the interface with 192.168.3.5/24, then delete the // "192.168.3.0/24 dev $ifName" route that was automatically added. Then we add // "192.168.3.1/32 dev $ifName" and "192.168.3.0/24 via 192.168.3.1 dev $ifName". // In other words we force all traffic to ARP via the gateway except for GW itself. var hostVethName string err := ns.WithNetNSPath(netns, false, func(hostNS *os.File) error { hostVeth, _, err := ip.SetupVeth(ifName, mtu, hostNS) if err != nil { return err } if err = ipam.ConfigureIface(ifName, pr); err != nil { return err } contVeth, err := netlink.LinkByName(ifName) if err != nil { return fmt.Errorf("failed to look up %q: %v", ifName, err) } // Delete the route that was automatically added route := netlink.Route{ LinkIndex: contVeth.Attrs().Index, Dst: &net.IPNet{ IP: pr.IP4.IP.IP.Mask(pr.IP4.IP.Mask), Mask: pr.IP4.IP.Mask, }, Scope: netlink.SCOPE_NOWHERE, } if err := netlink.RouteDel(&route); err != nil { return fmt.Errorf("failed to delete route %v: %v", route, err) } for _, r := range []netlink.Route{ netlink.Route{ LinkIndex: contVeth.Attrs().Index, Dst: &net.IPNet{ IP: pr.IP4.Gateway, Mask: net.CIDRMask(32, 32), }, Scope: netlink.SCOPE_LINK, Src: pr.IP4.IP.IP, }, netlink.Route{ LinkIndex: contVeth.Attrs().Index, Dst: &net.IPNet{ IP: pr.IP4.IP.IP.Mask(pr.IP4.IP.Mask), Mask: pr.IP4.IP.Mask, }, Scope: netlink.SCOPE_UNIVERSE, Gw: pr.IP4.Gateway, Src: pr.IP4.IP.IP, }, } { if err := netlink.RouteAdd(&r); err != nil { return fmt.Errorf("failed to add route %v: %v", r, err) } } hostVethName = hostVeth.Attrs().Name return nil }) return hostVethName, err }