Ejemplo n.º 1
0
// XfrmStateAdd will add an xfrm state to the system.
// Equivalent to: `ip xfrm state add $state`
func XfrmStateAdd(state *XfrmState) error {
	// A state with spi 0 can't be deleted so don't allow it to be set
	if state.Spi == 0 {
		return fmt.Errorf("Spi must be set when adding xfrm state.")
	}
	req := nl.NewNetlinkRequest(nl.XFRM_MSG_NEWSA, syscall.NLM_F_CREATE|syscall.NLM_F_EXCL|syscall.NLM_F_ACK)

	msg := &nl.XfrmUsersaInfo{}
	msg.Family = uint16(nl.GetIPFamily(state.Dst))
	msg.Id.Daddr.FromIP(state.Dst)
	msg.Saddr.FromIP(state.Src)
	msg.Id.Proto = uint8(state.Proto)
	msg.Mode = uint8(state.Mode)
	msg.Id.Spi = nl.Swap32(uint32(state.Spi))
	msg.Reqid = uint32(state.Reqid)
	msg.ReplayWindow = uint8(state.ReplayWindow)
	msg.Lft.SoftByteLimit = nl.XFRM_INF
	msg.Lft.HardByteLimit = nl.XFRM_INF
	msg.Lft.SoftPacketLimit = nl.XFRM_INF
	msg.Lft.HardPacketLimit = nl.XFRM_INF
	req.AddData(msg)

	if state.Auth != nil {
		out := nl.NewRtAttr(nl.XFRMA_ALG_AUTH_TRUNC, writeStateAlgoAuth(state.Auth))
		req.AddData(out)
	}
	if state.Crypt != nil {
		out := nl.NewRtAttr(nl.XFRMA_ALG_CRYPT, writeStateAlgo(state.Crypt))
		req.AddData(out)
	}
	if state.Encap != nil {
		encapData := make([]byte, nl.SizeofXfrmEncapTmpl)
		encap := nl.DeserializeXfrmEncapTmpl(encapData)
		encap.EncapType = uint16(state.Encap.Type)
		encap.EncapSport = nl.Swap16(uint16(state.Encap.SrcPort))
		encap.EncapDport = nl.Swap16(uint16(state.Encap.DstPort))
		encap.EncapOa.FromIP(state.Encap.OriginalAddress)
		out := nl.NewRtAttr(nl.XFRMA_ENCAP, encapData)
		req.AddData(out)
	}

	_, err := req.Execute(syscall.NETLINK_XFRM, 0)
	return err
}
Ejemplo n.º 2
0
// FilterDel will delete a filter from the system.
// Equivalent to: `tc filter del $filter`
func FilterDel(filter Filter) error {
	req := nl.NewNetlinkRequest(syscall.RTM_DELTFILTER, 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)

	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}
Ejemplo n.º 3
0
// XfrmStateList gets a list of xfrm states in the system.
// Equivalent to: `ip xfrm state show`.
// The list can be filtered by ip family.
func XfrmStateList(family int) ([]XfrmState, error) {
	req := nl.NewNetlinkRequest(nl.XFRM_MSG_GETSA, syscall.NLM_F_DUMP)

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

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

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

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

		var state XfrmState

		state.Dst = msg.Id.Daddr.ToIP()
		state.Src = msg.Saddr.ToIP()
		state.Proto = Proto(msg.Id.Proto)
		state.Mode = Mode(msg.Mode)
		state.Spi = int(nl.Swap32(msg.Id.Spi))
		state.Reqid = int(msg.Reqid)
		state.ReplayWindow = int(msg.ReplayWindow)

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

		for _, attr := range attrs {
			switch attr.Attr.Type {
			case nl.XFRMA_ALG_AUTH, nl.XFRMA_ALG_CRYPT:
				var resAlgo *XfrmStateAlgo
				if attr.Attr.Type == nl.XFRMA_ALG_AUTH {
					if state.Auth == nil {
						state.Auth = new(XfrmStateAlgo)
					}
					resAlgo = state.Auth
				} else {
					state.Crypt = new(XfrmStateAlgo)
					resAlgo = state.Crypt
				}
				algo := nl.DeserializeXfrmAlgo(attr.Value[:])
				(*resAlgo).Name = nl.BytesToString(algo.AlgName[:])
				(*resAlgo).Key = algo.AlgKey
			case nl.XFRMA_ALG_AUTH_TRUNC:
				if state.Auth == nil {
					state.Auth = new(XfrmStateAlgo)
				}
				algo := nl.DeserializeXfrmAlgoAuth(attr.Value[:])
				state.Auth.Name = nl.BytesToString(algo.AlgName[:])
				state.Auth.Key = algo.AlgKey
				state.Auth.TruncateLen = int(algo.AlgTruncLen)
			case nl.XFRMA_ENCAP:
				encap := nl.DeserializeXfrmEncapTmpl(attr.Value[:])
				state.Encap = new(XfrmStateEncap)
				state.Encap.Type = EncapType(encap.EncapType)
				state.Encap.SrcPort = int(nl.Swap16(encap.EncapSport))
				state.Encap.DstPort = int(nl.Swap16(encap.EncapDport))
				state.Encap.OriginalAddress = encap.EncapOa.ToIP()
			}

		}
		res = append(res, state)
	}
	return res, nil
}
Ejemplo n.º 4
0
// 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())
		actions := nl.NewRtAttrChild(options, nl.TCA_U32_ACT, nil)
		table := nl.NewRtAttrChild(actions, nl.TCA_ACT_TAB, nil)
		nl.NewRtAttrChild(table, nl.TCA_KIND, nl.ZeroTerminated("mirred"))
		// redirect to other interface
		mir := nl.TcMirred{
			Action:  nl.TC_ACT_STOLEN,
			Eaction: nl.TCA_EGRESS_REDIR,
			Ifindex: uint32(u32.RedirIndex),
		}
		aopts := nl.NewRtAttrChild(table, nl.TCA_OPTIONS, nil)
		nl.NewRtAttrChild(aopts, nl.TCA_MIRRED_PARMS, mir.Serialize())
	} 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)
		}
	}

	req.AddData(options)
	_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
	return err
}
Ejemplo n.º 5
0
// FilterList gets a list of filters in the system.
// Equivalent to: `tc filter show`.
// Generally retunrs nothing if link and parent are not specified.
func FilterList(link Link, parent uint32) ([]Filter, error) {
	req := nl.NewNetlinkRequest(syscall.RTM_GETTFILTER, syscall.NLM_F_DUMP)
	msg := &nl.TcMsg{
		Family: nl.FAMILY_ALL,
		Parent: parent,
	}
	if link != nil {
		base := link.Attrs()
		ensureIndex(base)
		msg.Ifindex = int32(base.Index)
	}
	req.AddData(msg)

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

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

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

		base := FilterAttrs{
			LinkIndex: int(msg.Ifindex),
			Handle:    msg.Handle,
			Parent:    msg.Parent,
		}
		base.Priority, base.Protocol = MajorMinor(msg.Info)
		base.Protocol = nl.Swap16(base.Protocol)

		var filter Filter
		filterType := ""
		detailed := false
		for _, attr := range attrs {
			switch attr.Attr.Type {
			case nl.TCA_KIND:
				filterType = string(attr.Value[:len(attr.Value)-1])
				switch filterType {
				case "u32":
					filter = &U32{}
				case "fw":
					filter = &Fw{}
				default:
					filter = &GenericFilter{FilterType: filterType}
				}
			case nl.TCA_OPTIONS:
				switch filterType {
				case "u32":
					data, err := nl.ParseRouteAttr(attr.Value)
					if err != nil {
						return nil, err
					}
					detailed, err = parseU32Data(filter, data)
					if err != nil {
						return nil, err
					}
				case "fw":
					data, err := nl.ParseRouteAttr(attr.Value)
					if err != nil {
						return nil, err
					}
					detailed, err = parseFwData(filter, data)
					if err != nil {
						return nil, err
					}
				}
			}
		}
		// only return the detailed version of the filter
		if detailed {
			*filter.Attrs() = base
			res = append(res, filter)
		}
	}

	return res, nil
}