Golang nl.NewIfInfomsg函数代码示例

// LinkList gets a list of link devices.
// Equivalent to: `ip link show`
func LinkList() ([]Link, error) {
	// NOTE(vish): This duplicates functionality in net/iface_linux.go, but we need
	//             to get the message ourselves to parse link type.
	req := nl.NewNetlinkRequest(syscall.RTM_GETLINK, syscall.NLM_F_DUMP)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	req.AddData(msg)

	msgs, err := req.Execute(syscall.NETLINK_ROUTE, syscall.RTM_NEWLINK)
	if err != nil {
		return nil, err
	}

	res := make([]Link, 0)

	for _, m := range msgs {
		link, err := linkDeserialize(m)
		if err != nil {
			return nil, err
		}
		res = append(res, link)
	}

	return res, nil
}

// LinkByIndex finds a link by index and returns a pointer to the object.
func LinkByIndex(index int) (Link, error) {
	req := nl.NewNetlinkRequest(syscall.RTM_GETLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	msg.Index = int32(index)
	req.AddData(msg)

	return execGetLink(req)
}

// XfrmPolicyList gets a list of xfrm policies in the system.
// Equivalent to: `ip xfrm policy show`.
// The list can be filtered by ip family.
func XfrmPolicyList(family int) ([]XfrmPolicy, error) {
	req := nl.NewNetlinkRequest(nl.XFRM_MSG_GETPOLICY, syscall.NLM_F_DUMP)

	msg := nl.NewIfInfomsg(family)
	req.AddData(msg)

	msgs, err := req.Execute(syscall.NETLINK_XFRM, nl.XFRM_MSG_NEWPOLICY)
	if err != nil {
		return nil, err
	}

	var res []XfrmPolicy
	for _, m := range msgs {
		msg := nl.DeserializeXfrmUserpolicyInfo(m)

		if family != FAMILY_ALL && family != int(msg.Sel.Family) {
			continue
		}

		var policy XfrmPolicy

		policy.Dst = msg.Sel.Daddr.ToIPNet(msg.Sel.PrefixlenD)
		policy.Src = msg.Sel.Saddr.ToIPNet(msg.Sel.PrefixlenS)
		policy.Priority = int(msg.Priority)
		policy.Index = int(msg.Index)
		policy.Dir = Dir(msg.Dir)

		attrs, err := nl.ParseRouteAttr(m[msg.Len():])
		if err != nil {
			return nil, err
		}

		for _, attr := range attrs {
			switch attr.Attr.Type {
			case nl.XFRMA_TMPL:
				max := len(attr.Value)
				for i := 0; i < max; i += nl.SizeofXfrmUserTmpl {
					var resTmpl XfrmPolicyTmpl
					tmpl := nl.DeserializeXfrmUserTmpl(attr.Value[i : i+nl.SizeofXfrmUserTmpl])
					resTmpl.Dst = tmpl.XfrmId.Daddr.ToIP()
					resTmpl.Src = tmpl.Saddr.ToIP()
					resTmpl.Proto = Proto(tmpl.XfrmId.Proto)
					resTmpl.Mode = Mode(tmpl.Mode)
					resTmpl.Reqid = int(tmpl.Reqid)
					policy.Tmpls = append(policy.Tmpls, resTmpl)
				}
			}
		}
		res = append(res, policy)
	}
	return res, nil
}

func LinkGetProtinfo(link Link) (Protinfo, error) {
	base := link.Attrs()
	ensureIndex(base)
	var pi Protinfo
	req := nl.NewNetlinkRequest(syscall.RTM_GETLINK, syscall.NLM_F_DUMP)
	msg := nl.NewIfInfomsg(syscall.AF_BRIDGE)
	req.AddData(msg)
	msgs, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	if err != nil {
		return pi, err
	}

	for _, m := range msgs {
		ans := nl.DeserializeIfInfomsg(m)
		if int(ans.Index) != base.Index {
			continue
		}
		attrs, err := nl.ParseRouteAttr(m[ans.Len():])
		if err != nil {
			return pi, err
		}
		for _, attr := range attrs {
			if attr.Attr.Type != syscall.IFLA_PROTINFO|syscall.NLA_F_NESTED {
				continue
			}
			infos, err := nl.ParseRouteAttr(attr.Value)
			if err != nil {
				return pi, err
			}
			var pi Protinfo
			for _, info := range infos {
				switch info.Attr.Type {
				case nl.IFLA_BRPORT_MODE:
					pi.Hairpin = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_GUARD:
					pi.Guard = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_FAST_LEAVE:
					pi.FastLeave = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_PROTECT:
					pi.RootBlock = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_LEARNING:
					pi.Learning = byteToBool(info.Value[0])
				case nl.IFLA_BRPORT_UNICAST_FLOOD:
					pi.Flood = byteToBool(info.Value[0])
				}
			}
			return pi, nil
		}
	}
	return pi, fmt.Errorf("Device with index %d not found", base.Index)
}

// LinkDel deletes link device. Either Index or Name must be set in
// the link object for it to be deleted. The other values are ignored.
// Equivalent to: `ip link del $link`
func LinkDel(link Link) error {
	base := link.Attrs()

	ensureIndex(base)

	req := nl.NewNetlinkRequest(syscall.RTM_DELLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	msg.Index = int32(base.Index)
	req.AddData(msg)

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}

// LinkSetDown disables link device.
// Equivalent to: `ip link set $link down`
func LinkSetDown(link Link) error {
	base := link.Attrs()
	ensureIndex(base)
	req := nl.NewNetlinkRequest(syscall.RTM_NEWLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	msg.Change = syscall.IFF_UP
	msg.Flags = 0 & ^syscall.IFF_UP
	msg.Index = int32(base.Index)
	req.AddData(msg)

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}

// LinkSetHardwareAddr sets the hardware address of the link device.
// Equivalent to: `ip link set $link address $hwaddr`
func LinkSetHardwareAddr(link Link, hwaddr net.HardwareAddr) error {
	base := link.Attrs()
	ensureIndex(base)
	req := nl.NewNetlinkRequest(syscall.RTM_SETLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	msg.Index = int32(base.Index)
	req.AddData(msg)

	data := nl.NewRtAttr(syscall.IFLA_ADDRESS, []byte(hwaddr))
	req.AddData(data)

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}

// LinkSetName sets the name of the link device.
// Equivalent to: `ip link set $link name $name`
func LinkSetName(link Link, name string) error {
	base := link.Attrs()
	ensureIndex(base)
	req := nl.NewNetlinkRequest(syscall.RTM_SETLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	msg.Index = int32(base.Index)
	req.AddData(msg)

	data := nl.NewRtAttr(syscall.IFLA_IFNAME, []byte(name))
	req.AddData(data)

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}

// RouteList gets a list of routes in the system.
// Equivalent to: `ip route show`.
// The list can be filtered by link and ip family.
func RouteList(link Link, family int) ([]Route, error) {
	req := nl.NewNetlinkRequest(syscall.RTM_GETROUTE, syscall.NLM_F_DUMP)
	msg := nl.NewIfInfomsg(family)
	req.AddData(msg)

	msgs, err := req.Execute(syscall.NETLINK_ROUTE, syscall.RTM_NEWROUTE)
	if err != nil {
		return nil, err
	}

	index := 0
	if link != nil {
		base := link.Attrs()
		ensureIndex(base)
		index = base.Index
	}

	var res []Route
	for _, m := range msgs {
		msg := nl.DeserializeRtMsg(m)

		if msg.Flags&syscall.RTM_F_CLONED != 0 {
			// Ignore cloned routes
			continue
		}

		if msg.Table != syscall.RT_TABLE_MAIN {
			// Ignore non-main tables
			continue
		}

		route, err := deserializeRoute(m)
		if err != nil {
			return nil, err
		}

		if link != nil && route.LinkIndex != index {
			// Ignore routes from other interfaces
			continue
		}
		res = append(res, route)
	}

	return res, nil
}

func setProtinfoAttr(link Link, mode bool, attr int) error {
	base := link.Attrs()
	ensureIndex(base)
	req := nl.NewNetlinkRequest(syscall.RTM_SETLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_BRIDGE)
	msg.Index = int32(base.Index)
	req.AddData(msg)

	br := nl.NewRtAttr(syscall.IFLA_PROTINFO|syscall.NLA_F_NESTED, nil)
	nl.NewRtAttrChild(br, attr, boolToByte(mode))
	req.AddData(br)
	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	if err != nil {
		return err
	}
	return nil
}

// LinkSetMTU sets the mtu of the link device.
// Equivalent to: `ip link set $link mtu $mtu`
func LinkSetMTU(link Link, mtu int) error {
	base := link.Attrs()
	ensureIndex(base)
	req := nl.NewNetlinkRequest(syscall.RTM_SETLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	msg.Index = int32(base.Index)
	req.AddData(msg)

	b := make([]byte, 4)
	native.PutUint32(b, uint32(mtu))

	data := nl.NewRtAttr(syscall.IFLA_MTU, b)
	req.AddData(data)

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}

// LinkSetNsFd puts the device into a new network namespace. The
// fd must be an open file descriptor to a network namespace.
// Similar to: `ip link set $link netns $ns`
func LinkSetNsFd(link Link, fd int) error {
	base := link.Attrs()
	ensureIndex(base)
	req := nl.NewNetlinkRequest(syscall.RTM_SETLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	msg.Type = syscall.RTM_SETLINK
	msg.Flags = syscall.NLM_F_REQUEST
	msg.Index = int32(base.Index)
	msg.Change = nl.IFLA_NET_NS_FD
	req.AddData(msg)

	b := make([]byte, 4)
	native.PutUint32(b, uint32(fd))

	data := nl.NewRtAttr(nl.IFLA_NET_NS_FD, b)
	req.AddData(data)

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}

// LinkByName finds a link by name and returns a pointer to the object.
func LinkByName(name string) (Link, error) {
	if lookupByDump {
		return linkByNameDump(name)
	}

	req := nl.NewNetlinkRequest(syscall.RTM_GETLINK, syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	req.AddData(msg)

	nameData := nl.NewRtAttr(syscall.IFLA_IFNAME, nl.ZeroTerminated(name))
	req.AddData(nameData)

	link, err := execGetLink(req)
	if err == syscall.EINVAL {
		// older kernels don't support looking up via IFLA_IFNAME
		// so fall back to dumping all links
		lookupByDump = true
		return linkByNameDump(name)
	}

	return link, err
}

// LinkAdd adds a new link device. The type and features of the device
// are taken fromt the parameters in the link object.
// Equivalent to: `ip link add $link`
func LinkAdd(link Link) error {
	// TODO: set mtu and hardware address
	// TODO: support extra data for macvlan
	base := link.Attrs()

	if base.Name == "" {
		return fmt.Errorf("LinkAttrs.Name cannot be empty!")
	}

	if tuntap, ok := link.(*Tuntap); ok {
		// TODO: support user
		// TODO: support group
		// TODO: support non- one_queue
		// TODO: support pi | vnet_hdr | multi_queue
		// TODO: support non- exclusive
		// TODO: support non- persistent
		if tuntap.Mode < syscall.IFF_TUN || tuntap.Mode > syscall.IFF_TAP {
			return fmt.Errorf("Tuntap.Mode %v unknown!", tuntap.Mode)
		}
		file, err := os.OpenFile("/dev/net/tun", os.O_RDWR, 0)
		if err != nil {
			return err
		}
		defer file.Close()
		var req ifReq
		req.Flags |= syscall.IFF_ONE_QUEUE
		req.Flags |= syscall.IFF_TUN_EXCL
		copy(req.Name[:15], base.Name)
		req.Flags |= uint16(tuntap.Mode)
		_, _, errno := syscall.Syscall(syscall.SYS_IOCTL, file.Fd(), uintptr(syscall.TUNSETIFF), uintptr(unsafe.Pointer(&req)))
		if errno != 0 {
			return fmt.Errorf("Tuntap IOCTL TUNSETIFF failed, errno %v", errno)
		}
		_, _, errno = syscall.Syscall(syscall.SYS_IOCTL, file.Fd(), uintptr(syscall.TUNSETPERSIST), 1)
		if errno != 0 {
			return fmt.Errorf("Tuntap IOCTL TUNSETPERSIST failed, errno %v", errno)
		}
		ensureIndex(base)

		// can't set master during create, so set it afterwards
		if base.MasterIndex != 0 {
			// TODO: verify MasterIndex is actually a bridge?
			return LinkSetMasterByIndex(link, base.MasterIndex)
		}
		return nil
	}

	req := nl.NewNetlinkRequest(syscall.RTM_NEWLINK, syscall.NLM_F_CREATE|syscall.NLM_F_EXCL|syscall.NLM_F_ACK)

	msg := nl.NewIfInfomsg(syscall.AF_UNSPEC)
	req.AddData(msg)

	if base.ParentIndex != 0 {
		b := make([]byte, 4)
		native.PutUint32(b, uint32(base.ParentIndex))
		data := nl.NewRtAttr(syscall.IFLA_LINK, b)
		req.AddData(data)
	} else if link.Type() == "ipvlan" {
		return fmt.Errorf("Can't create ipvlan link without ParentIndex")
	}

	nameData := nl.NewRtAttr(syscall.IFLA_IFNAME, nl.ZeroTerminated(base.Name))
	req.AddData(nameData)

	if base.MTU > 0 {
		mtu := nl.NewRtAttr(syscall.IFLA_MTU, nl.Uint32Attr(uint32(base.MTU)))
		req.AddData(mtu)
	}

	if base.TxQLen >= 0 {
		qlen := nl.NewRtAttr(syscall.IFLA_TXQLEN, nl.Uint32Attr(uint32(base.TxQLen)))
		req.AddData(qlen)
	}

	if base.Namespace != nil {
		var attr *nl.RtAttr
		switch base.Namespace.(type) {
		case NsPid:
			val := nl.Uint32Attr(uint32(base.Namespace.(NsPid)))
			attr = nl.NewRtAttr(syscall.IFLA_NET_NS_PID, val)
		case NsFd:
			val := nl.Uint32Attr(uint32(base.Namespace.(NsFd)))
			attr = nl.NewRtAttr(nl.IFLA_NET_NS_FD, val)
		}

		req.AddData(attr)
	}

	linkInfo := nl.NewRtAttr(syscall.IFLA_LINKINFO, nil)
	nl.NewRtAttrChild(linkInfo, nl.IFLA_INFO_KIND, nl.NonZeroTerminated(link.Type()))

	if vlan, ok := link.(*Vlan); ok {
		b := make([]byte, 2)
		native.PutUint16(b, uint16(vlan.VlanId))
		data := nl.NewRtAttrChild(linkInfo, nl.IFLA_INFO_DATA, nil)
		nl.NewRtAttrChild(data, nl.IFLA_VLAN_ID, b)
	} else if veth, ok := link.(*Veth); ok {
//.........这里部分代码省略.........

// RouteList gets a list of routes in the system.
// Equivalent to: `ip route show`.
// The list can be filtered by link and ip family.
func RouteList(link Link, family int) ([]Route, error) {
	req := nl.NewNetlinkRequest(syscall.RTM_GETROUTE, syscall.NLM_F_DUMP)
	msg := nl.NewIfInfomsg(family)
	req.AddData(msg)

	msgs, err := req.Execute(syscall.NETLINK_ROUTE, syscall.RTM_NEWROUTE)
	if err != nil {
		return nil, err
	}

	index := 0
	if link != nil {
		base := link.Attrs()
		ensureIndex(base)
		index = base.Index
	}

	native := nl.NativeEndian()
	res := make([]Route, 0)
	for _, m := range msgs {
		msg := nl.DeserializeRtMsg(m)

		if msg.Flags&syscall.RTM_F_CLONED != 0 {
			// Ignore cloned routes
			continue
		}

		if msg.Table != syscall.RT_TABLE_MAIN {
			// Ignore non-main tables
			continue
		}

		attrs, err := nl.ParseRouteAttr(m[msg.Len():])
		if err != nil {
			return nil, err
		}

		route := Route{Scope: Scope(msg.Scope)}
		for _, attr := range attrs {
			switch attr.Attr.Type {
			case syscall.RTA_GATEWAY:
				route.Gw = net.IP(attr.Value)
			case syscall.RTA_PREFSRC:
				route.Src = net.IP(attr.Value)
			case syscall.RTA_DST:
				route.Dst = &net.IPNet{
					IP:   attr.Value,
					Mask: net.CIDRMask(int(msg.Dst_len), 8*len(attr.Value)),
				}
			case syscall.RTA_OIF:
				routeIndex := int(native.Uint32(attr.Value[0:4]))
				if link != nil && routeIndex != index {
					// Ignore routes from other interfaces
					continue
				}
				route.LinkIndex = routeIndex
			}
		}
		res = append(res, route)
	}

	return res, nil
}