func()

in plugins/vpc-shared-eni/network/bridge_linux.go [853:933]

• 64 lines of code
• 9 McCabe index (conditional complexity)

func (nb *BridgeBuilder) setupTapLink(linkName string, tapLinkName string, uid int) error {
	// Create the bridge link.
	la := netlink.NewLinkAttrs()
	la.Name = tapBridgeName
	la.MTU = vpc.JumboFrameMTU
	bridge := &netlink.Bridge{LinkAttrs: la}
	log.Infof("Creating bridge link %+v.", bridge)
	err := netlink.LinkAdd(bridge)
	if err != nil {
		log.Errorf("Failed to create bridge link: %v", err)
		return err
	}

	// Set bridge link MTU.
	err = netlink.LinkSetMTU(bridge, vpc.JumboFrameMTU)
	if err != nil {
		log.Errorf("Failed to set bridge link MTU: %v", err)
		return err
	}

	// Set bridge link operational state up.
	err = netlink.LinkSetUp(bridge)
	if err != nil {
		log.Errorf("Failed to set bridge link state: %v", err)
		return err
	}

	// Connect link to the bridge.
	la = netlink.NewLinkAttrs()
	la.Name = linkName
	link := &netlink.Dummy{LinkAttrs: la}
	err = netlink.LinkSetMaster(link, bridge)
	if err != nil {
		log.Errorf("Failed to set link master: %v", err)
		return err
	}

	// Create the TAP link.
	la = netlink.NewLinkAttrs()
	la.Name = tapLinkName
	la.MasterIndex = bridge.Index
	la.MTU = vpc.JumboFrameMTU
	tapLink := &netlink.Tuntap{
		LinkAttrs: la,
		Mode:      netlink.TUNTAP_MODE_TAP,
		Flags:     netlink.TUNTAP_ONE_QUEUE | netlink.TUNTAP_VNET_HDR,
		Queues:    1,
	}

	log.Infof("Creating TAP link %+v.", tapLink)
	err = netlink.LinkAdd(tapLink)
	if err != nil {
		log.Errorf("Failed to add TAP link: %v", err)
		return err
	}

	// Set TAP link MTU.
	err = netlink.LinkSetMTU(tapLink, vpc.JumboFrameMTU)
	if err != nil {
		log.Errorf("Failed to set TAP link MTU: %v", err)
		return err
	}

	// Set TAP link ownership.
	log.Infof("Setting TAP link owner to uid %d.", uid)
	fd := int(tapLink.Fds[0].Fd())
	err = unix.IoctlSetInt(fd, unix.TUNSETOWNER, uid)
	if err != nil {
		log.Errorf("Failed to set TAP link owner: %v", err)
		return err
	}

	// Set TAP link operational state up.
	err = netlink.LinkSetUp(tapLink)
	if err != nil {
		log.Errorf("Failed to set TAP link state: %v", err)
		return err
	}

	return nil
}