Golang nl.NativeEndian函数代码示例

func parseFwData(filter Filter, data []syscall.NetlinkRouteAttr) (bool, error) {
	native = nl.NativeEndian()
	fw := filter.(*Fw)
	detailed := true
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_FW_MASK:
			fw.Mask = native.Uint32(datum.Value[0:4])
		case nl.TCA_FW_CLASSID:
			fw.ClassId = native.Uint32(datum.Value[0:4])
		case nl.TCA_FW_INDEV:
			fw.InDev = string(datum.Value[:len(datum.Value)-1])
		case nl.TCA_FW_POLICE:
			adata, _ := nl.ParseRouteAttr(datum.Value)
			for _, aattr := range adata {
				switch aattr.Attr.Type {
				case nl.TCA_POLICE_TBF:
					fw.Police = *nl.DeserializeTcPolice(aattr.Value)
				case nl.TCA_POLICE_RATE:
					fw.Rtab = DeserializeRtab(aattr.Value)
				case nl.TCA_POLICE_PEAKRATE:
					fw.Ptab = DeserializeRtab(aattr.Value)
				}
			}
		}
	}
	return detailed, nil
}

func parseU32Data(filter Filter, data []syscall.NetlinkRouteAttr) (bool, error) {
	native = nl.NativeEndian()
	u32 := filter.(*U32)
	detailed := false
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_U32_SEL:
			detailed = true
			sel := nl.DeserializeTcU32Sel(datum.Value)
			// only parse if we have a very basic redirect
			if sel.Flags&nl.TC_U32_TERMINAL == 0 || sel.Nkeys != 1 {
				return detailed, nil
			}
		case nl.TCA_U32_ACT:
			tables, err := nl.ParseRouteAttr(datum.Value)
			if err != nil {
				return detailed, err
			}
			u32.Actions, err = parseActions(tables)
			if err != nil {
				return detailed, err
			}
			for _, action := range u32.Actions {
				if action, ok := action.(*MirredAction); ok {
					u32.RedirIndex = int(action.Ifindex)
				}
			}
		}
	}
	return detailed, nil
}

// deserializeRoute decodes a binary netlink message into a Route struct
func deserializeRoute(m []byte) (Route, error) {
	route := Route{}
	msg := nl.DeserializeRtMsg(m)
	attrs, err := nl.ParseRouteAttr(m[msg.Len():])
	if err != nil {
		return route, err
	}
	route.Scope = Scope(msg.Scope)
	route.Flags = int(msg.Flags)

	native := nl.NativeEndian()
	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]))
			route.LinkIndex = routeIndex
		}
	}
	return route, nil
}

func DeserializeRtab(b []byte) [256]uint32 {
	var rtab [256]uint32
	native := nl.NativeEndian()
	r := bytes.NewReader(b)
	_ = binary.Read(r, native, &rtab)
	return rtab
}

// Serialize serializes the message.
// Int32msg has the following representation
// | nlattr len | nlattr type |
// | uint32 value             |
func (msg *Int32msg) Serialize() []byte {
	buf := make([]byte, msg.Len())
	native := nl.NativeEndian()
	native.PutUint16(buf[0:2], uint16(msg.Len()))
	native.PutUint16(buf[2:4], msg.Type)
	native.PutUint32(buf[4:8], msg.Value)
	return buf
}

// RouteGet gets a route to a specific destination from the host system.
// Equivalent to: 'ip route get'.
func RouteGet(destination net.IP) ([]Route, error) {
	req := nl.NewNetlinkRequest(syscall.RTM_GETROUTE, syscall.NLM_F_REQUEST)
	family := nl.GetIPFamily(destination)
	var destinationData []byte
	var bitlen uint8
	if family == FAMILY_V4 {
		destinationData = destination.To4()
		bitlen = 32
	} else {
		destinationData = destination.To16()
		bitlen = 128
	}
	msg := &nl.RtMsg{}
	msg.Family = uint8(family)
	msg.Dst_len = bitlen
	req.AddData(msg)

	rtaDst := nl.NewRtAttr(syscall.RTA_DST, destinationData)
	req.AddData(rtaDst)

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

	native := nl.NativeEndian()
	var res []Route
	for _, m := range msgs {
		msg := nl.DeserializeRtMsg(m)
		attrs, err := nl.ParseRouteAttr(m[msg.Len():])
		if err != nil {
			return nil, err
		}

		route := Route{}
		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]))
				route.LinkIndex = routeIndex
			}
		}
		res = append(res, route)
	}
	return res, nil

}

func parseU32Data(filter Filter, data []syscall.NetlinkRouteAttr) (bool, error) {
	native = nl.NativeEndian()
	u32 := filter.(*U32)
	detailed := false
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_U32_SEL:
			detailed = true
			sel := nl.DeserializeTcU32Sel(datum.Value)
			// only parse if we have a very basic redirect
			if sel.Flags&nl.TC_U32_TERMINAL == 0 || sel.Nkeys != 1 {
				return detailed, nil
			}
		case nl.TCA_U32_ACT:
			table, err := nl.ParseRouteAttr(datum.Value)
			if err != nil {
				return detailed, err
			}
			if len(table) != 1 || table[0].Attr.Type != nl.TCA_ACT_TAB {
				return detailed, fmt.Errorf("Action table not formed properly")
			}
			aattrs, err := nl.ParseRouteAttr(table[0].Value)
			for _, aattr := range aattrs {
				switch aattr.Attr.Type {
				case nl.TCA_KIND:
					actionType := string(aattr.Value[:len(aattr.Value)-1])
					// only parse if the action is mirred
					if actionType != "mirred" {
						return detailed, nil
					}
				case nl.TCA_OPTIONS:
					adata, err := nl.ParseRouteAttr(aattr.Value)
					if err != nil {
						return detailed, err
					}
					for _, adatum := range adata {
						switch adatum.Attr.Type {
						case nl.TCA_MIRRED_PARMS:
							mir := nl.DeserializeTcMirred(adatum.Value)
							u32.RedirIndex = int(mir.Ifindex)
						}
					}
				}
			}
		}
	}
	return detailed, nil
}

func parseTbfData(qdisc Qdisc, data []syscall.NetlinkRouteAttr) error {
	native = nl.NativeEndian()
	tbf := qdisc.(*Tbf)
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_TBF_PARMS:
			opt := nl.DeserializeTcTbfQopt(datum.Value)
			tbf.Rate = uint64(opt.Rate.Rate)
			tbf.Limit = opt.Limit
			tbf.Buffer = opt.Buffer
		case nl.TCA_TBF_RATE64:
			tbf.Rate = native.Uint64(datum.Value[0:4])
		}
	}
	return nil
}

func parseHtbData(qdisc Qdisc, data []syscall.NetlinkRouteAttr) error {
	native = nl.NativeEndian()
	htb := qdisc.(*Htb)
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_HTB_INIT:
			opt := nl.DeserializeTcHtbGlob(datum.Value)
			htb.Version = opt.Version
			htb.Rate2Quantum = opt.Rate2Quantum
			htb.Defcls = opt.Defcls
			htb.Debug = opt.Debug
			htb.DirectPkts = opt.DirectPkts
		case nl.TCA_HTB_DIRECT_QLEN:
			// TODO
			//htb.DirectQlen = native.uint32(datum.Value)
		}
	}
	return nil
}

func parseBpfData(filter Filter, data []syscall.NetlinkRouteAttr) (bool, error) {
	native = nl.NativeEndian()
	bpf := filter.(*BpfFilter)
	detailed := true
	for _, datum := range data {
		switch datum.Attr.Type {
		case nl.TCA_BPF_FD:
			bpf.Fd = int(native.Uint32(datum.Value[0:4]))
		case nl.TCA_BPF_NAME:
			bpf.Name = string(datum.Value[:len(datum.Value)-1])
		case nl.TCA_BPF_CLASSID:
			bpf.ClassId = native.Uint32(datum.Value[0:4])
		case nl.TCA_BPF_FLAGS:
			flags := native.Uint32(datum.Value[0:4])
			if (flags & nl.TCA_BPF_FLAG_ACT_DIRECT) != 0 {
				bpf.DirectAction = true
			}
		}
	}
	return detailed, nil
}

// deserializeRoute decodes a binary netlink message into a Route struct
func deserializeRoute(m []byte) (Route, error) {
	msg := nl.DeserializeRtMsg(m)
	attrs, err := nl.ParseRouteAttr(m[msg.Len():])
	if err != nil {
		return Route{}, err
	}
	route := Route{
		Scope:    Scope(msg.Scope),
		Protocol: int(msg.Protocol),
		Table:    int(msg.Table),
		Type:     int(msg.Type),
		Tos:      int(msg.Tos),
		Flags:    int(msg.Flags),
	}

	native := nl.NativeEndian()
	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:
			route.LinkIndex = int(native.Uint32(attr.Value[0:4]))
		case syscall.RTA_IIF:
			route.ILinkIndex = int(native.Uint32(attr.Value[0:4]))
		case syscall.RTA_PRIORITY:
			route.Priority = int(native.Uint32(attr.Value[0:4]))
		case syscall.RTA_TABLE:
			route.Table = int(native.Uint32(attr.Value[0:4]))
		}
	}
	return route, nil
}

func routeHandle(route *Route, req *nl.NetlinkRequest, msg *nl.RtMsg) error {
	if (route.Dst == nil || route.Dst.IP == nil) && route.Src == nil && route.Gw == nil {
		return fmt.Errorf("one of Dst.IP, Src, or Gw must not be nil")
	}

	msg.Scope = uint8(route.Scope)
	msg.Flags = uint32(route.Flags)
	family := -1
	var rtAttrs []*nl.RtAttr

	if route.Dst != nil && route.Dst.IP != nil {
		dstLen, _ := route.Dst.Mask.Size()
		msg.Dst_len = uint8(dstLen)
		dstFamily := nl.GetIPFamily(route.Dst.IP)
		family = dstFamily
		var dstData []byte
		if dstFamily == FAMILY_V4 {
			dstData = route.Dst.IP.To4()
		} else {
			dstData = route.Dst.IP.To16()
		}
		rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_DST, dstData))
	}

	if route.Src != nil {
		srcFamily := nl.GetIPFamily(route.Src)
		if family != -1 && family != srcFamily {
			return fmt.Errorf("source and destination ip are not the same IP family")
		}
		family = srcFamily
		var srcData []byte
		if srcFamily == FAMILY_V4 {
			srcData = route.Src.To4()
		} else {
			srcData = route.Src.To16()
		}
		// The commonly used src ip for routes is actually PREFSRC
		rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_PREFSRC, srcData))
	}

	if route.Gw != nil {
		gwFamily := nl.GetIPFamily(route.Gw)
		if family != -1 && family != gwFamily {
			return fmt.Errorf("gateway, source, and destination ip are not the same IP family")
		}
		family = gwFamily
		var gwData []byte
		if gwFamily == FAMILY_V4 {
			gwData = route.Gw.To4()
		} else {
			gwData = route.Gw.To16()
		}
		rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_GATEWAY, gwData))
	}

	msg.Family = uint8(family)

	req.AddData(msg)
	for _, attr := range rtAttrs {
		req.AddData(attr)
	}

	var (
		b      = make([]byte, 4)
		native = nl.NativeEndian()
	)
	native.PutUint32(b, uint32(route.LinkIndex))

	req.AddData(nl.NewRtAttr(syscall.RTA_OIF, b))

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

	"github.com/vishvananda/netns"
)

const SizeofLinkStats = 0x5c

const (
	TUNTAP_MODE_TUN  TuntapMode = syscall.IFF_TUN
	TUNTAP_MODE_TAP  TuntapMode = syscall.IFF_TAP
	TUNTAP_DEFAULTS  TuntapFlag = syscall.IFF_TUN_EXCL | syscall.IFF_ONE_QUEUE
	TUNTAP_VNET_HDR  TuntapFlag = syscall.IFF_VNET_HDR
	TUNTAP_TUN_EXCL  TuntapFlag = syscall.IFF_TUN_EXCL
	TUNTAP_NO_PI     TuntapFlag = syscall.IFF_NO_PI
	TUNTAP_ONE_QUEUE TuntapFlag = syscall.IFF_ONE_QUEUE
)

var native = nl.NativeEndian()
var lookupByDump = false

var macvlanModes = [...]uint32{
	0,
	nl.MACVLAN_MODE_PRIVATE,
	nl.MACVLAN_MODE_VEPA,
	nl.MACVLAN_MODE_BRIDGE,
	nl.MACVLAN_MODE_PASSTHRU,
	nl.MACVLAN_MODE_SOURCE,
}

func ensureIndex(link *LinkAttrs) {
	if link != nil && link.Index == 0 {
		newlink, _ := LinkByName(link.Name)
		if newlink != nil {

// FilterAdd will add a filter to the system.
// Equivalent to: `tc filter add $filter`
func FilterAdd(filter Filter) error {
	native = nl.NativeEndian()
	req := nl.NewNetlinkRequest(syscall.RTM_NEWTFILTER, syscall.NLM_F_CREATE|syscall.NLM_F_EXCL|syscall.NLM_F_ACK)
	base := filter.Attrs()
	msg := &nl.TcMsg{
		Family:  nl.FAMILY_ALL,
		Ifindex: int32(base.LinkIndex),
		Handle:  base.Handle,
		Parent:  base.Parent,
		Info:    MakeHandle(base.Priority, nl.Swap16(base.Protocol)),
	}
	req.AddData(msg)
	req.AddData(nl.NewRtAttr(nl.TCA_KIND, nl.ZeroTerminated(filter.Type())))

	options := nl.NewRtAttr(nl.TCA_OPTIONS, nil)
	if u32, ok := filter.(*U32); ok {
		// match all
		sel := nl.TcU32Sel{
			Nkeys: 1,
			Flags: nl.TC_U32_TERMINAL,
		}
		sel.Keys = append(sel.Keys, nl.TcU32Key{})
		nl.NewRtAttrChild(options, nl.TCA_U32_SEL, sel.Serialize())
		if u32.ClassId != 0 {
			nl.NewRtAttrChild(options, nl.TCA_U32_CLASSID, nl.Uint32Attr(u32.ClassId))
		}
		actionsAttr := nl.NewRtAttrChild(options, nl.TCA_U32_ACT, nil)
		// backwards compatibility
		if u32.RedirIndex != 0 {
			u32.Actions = append([]Action{NewMirredAction(u32.RedirIndex)}, u32.Actions...)
		}
		if err := encodeActions(actionsAttr, u32.Actions); err != nil {
			return err
		}
	} else if fw, ok := filter.(*Fw); ok {
		if fw.Mask != 0 {
			b := make([]byte, 4)
			native.PutUint32(b, fw.Mask)
			nl.NewRtAttrChild(options, nl.TCA_FW_MASK, b)
		}
		if fw.InDev != "" {
			nl.NewRtAttrChild(options, nl.TCA_FW_INDEV, nl.ZeroTerminated(fw.InDev))
		}
		if (fw.Police != nl.TcPolice{}) {

			police := nl.NewRtAttrChild(options, nl.TCA_FW_POLICE, nil)
			nl.NewRtAttrChild(police, nl.TCA_POLICE_TBF, fw.Police.Serialize())
			if (fw.Police.Rate != nl.TcRateSpec{}) {
				payload := SerializeRtab(fw.Rtab)
				nl.NewRtAttrChild(police, nl.TCA_POLICE_RATE, payload)
			}
			if (fw.Police.PeakRate != nl.TcRateSpec{}) {
				payload := SerializeRtab(fw.Ptab)
				nl.NewRtAttrChild(police, nl.TCA_POLICE_PEAKRATE, payload)
			}
		}
		if fw.ClassId != 0 {
			b := make([]byte, 4)
			native.PutUint32(b, fw.ClassId)
			nl.NewRtAttrChild(options, nl.TCA_FW_CLASSID, b)
		}
	} else if bpf, ok := filter.(*BpfFilter); ok {
		var bpf_flags uint32
		if bpf.ClassId != 0 {
			nl.NewRtAttrChild(options, nl.TCA_BPF_CLASSID, nl.Uint32Attr(bpf.ClassId))
		}
		if bpf.Fd >= 0 {
			nl.NewRtAttrChild(options, nl.TCA_BPF_FD, nl.Uint32Attr((uint32(bpf.Fd))))
		}
		if bpf.Name != "" {
			nl.NewRtAttrChild(options, nl.TCA_BPF_NAME, nl.ZeroTerminated(bpf.Name))
		}
		if bpf.DirectAction {
			bpf_flags |= nl.TCA_BPF_FLAG_ACT_DIRECT
		}
		nl.NewRtAttrChild(options, nl.TCA_BPF_FLAGS, nl.Uint32Attr(bpf_flags))
	}

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

// RuleList lists rules in the system.
// Equivalent to: ip rule list
func RuleList(family int) ([]Rule, error) {
	req := nl.NewNetlinkRequest(syscall.RTM_GETRULE, syscall.NLM_F_DUMP|syscall.NLM_F_REQUEST)
	msg := nl.NewIfInfomsg(family)
	req.AddData(msg)

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

	native := nl.NativeEndian()
	var res = make([]Rule, 0)
	for i := range msgs {
		msg := nl.DeserializeRtMsg(msgs[i])
		attrs, err := nl.ParseRouteAttr(msgs[i][msg.Len():])
		if err != nil {
			return nil, err
		}

		rule := NewRule()
		rule.RtMsg = msg

		for j := range attrs {
			switch attrs[j].Attr.Type {
			case syscall.RTA_TABLE:
				rule.Table = int(native.Uint32(attrs[j].Value[0:4]))
			case nl.FRA_SRC:
				rule.Src = &net.IPNet{
					IP:   attrs[j].Value,
					Mask: net.CIDRMask(int(msg.Src_len), 8*len(attrs[j].Value)),
				}
			case nl.FRA_DST:
				rule.Dst = &net.IPNet{
					IP:   attrs[j].Value,
					Mask: net.CIDRMask(int(msg.Dst_len), 8*len(attrs[j].Value)),
				}
			case nl.FRA_FWMARK:
				rule.Mark = int(native.Uint32(attrs[j].Value[0:4]))
			case nl.FRA_FWMASK:
				rule.Mask = int(native.Uint32(attrs[j].Value[0:4]))
			case nl.FRA_TUN_ID:
				rule.TunID = uint(native.Uint64(attrs[j].Value[0:4]))
			case nl.FRA_IIFNAME:
				rule.IifName = string(attrs[j].Value[:len(attrs[j].Value)-1])
			case nl.FRA_OIFNAME:
				rule.OifName = string(attrs[j].Value[:len(attrs[j].Value)-1])
			case nl.FRA_SUPPRESS_PREFIXLEN:
				i := native.Uint32(attrs[j].Value[0:4])
				if i != 0xffffffff {
					rule.SuppressPrefixlen = int(i)
				}
			case nl.FRA_SUPPRESS_IFGROUP:
				i := native.Uint32(attrs[j].Value[0:4])
				if i != 0xffffffff {
					rule.SuppressIfgroup = int(i)
				}
			case nl.FRA_FLOW:
				rule.Flow = int(native.Uint32(attrs[j].Value[0:4]))
			case nl.FRA_GOTO:
				rule.Goto = int(native.Uint32(attrs[j].Value[0:4]))
			case nl.FRA_PRIORITY:
				rule.Priority = int(native.Uint32(attrs[j].Value[0:4]))
			}
		}
		res = append(res, *rule)
	}

	return res, nil
}