diff options
Diffstat (limited to 'vendor/github.com/vishvananda/netlink/route_linux.go')
-rw-r--r-- | vendor/github.com/vishvananda/netlink/route_linux.go | 674 |
1 files changed, 674 insertions, 0 deletions
diff --git a/vendor/github.com/vishvananda/netlink/route_linux.go b/vendor/github.com/vishvananda/netlink/route_linux.go new file mode 100644 index 000000000..cd739e714 --- /dev/null +++ b/vendor/github.com/vishvananda/netlink/route_linux.go @@ -0,0 +1,674 @@ +package netlink + +import ( + "fmt" + "net" + "strings" + "syscall" + + "github.com/vishvananda/netlink/nl" + "github.com/vishvananda/netns" +) + +// RtAttr is shared so it is in netlink_linux.go + +const ( + SCOPE_UNIVERSE Scope = syscall.RT_SCOPE_UNIVERSE + SCOPE_SITE Scope = syscall.RT_SCOPE_SITE + SCOPE_LINK Scope = syscall.RT_SCOPE_LINK + SCOPE_HOST Scope = syscall.RT_SCOPE_HOST + SCOPE_NOWHERE Scope = syscall.RT_SCOPE_NOWHERE +) + +const ( + RT_FILTER_PROTOCOL uint64 = 1 << (1 + iota) + RT_FILTER_SCOPE + RT_FILTER_TYPE + RT_FILTER_TOS + RT_FILTER_IIF + RT_FILTER_OIF + RT_FILTER_DST + RT_FILTER_SRC + RT_FILTER_GW + RT_FILTER_TABLE +) + +const ( + FLAG_ONLINK NextHopFlag = syscall.RTNH_F_ONLINK + FLAG_PERVASIVE NextHopFlag = syscall.RTNH_F_PERVASIVE +) + +var testFlags = []flagString{ + {f: FLAG_ONLINK, s: "onlink"}, + {f: FLAG_PERVASIVE, s: "pervasive"}, +} + +func listFlags(flag int) []string { + var flags []string + for _, tf := range testFlags { + if flag&int(tf.f) != 0 { + flags = append(flags, tf.s) + } + } + return flags +} + +func (r *Route) ListFlags() []string { + return listFlags(r.Flags) +} + +func (n *NexthopInfo) ListFlags() []string { + return listFlags(n.Flags) +} + +type MPLSDestination struct { + Labels []int +} + +func (d *MPLSDestination) Family() int { + return nl.FAMILY_MPLS +} + +func (d *MPLSDestination) Decode(buf []byte) error { + d.Labels = nl.DecodeMPLSStack(buf) + return nil +} + +func (d *MPLSDestination) Encode() ([]byte, error) { + return nl.EncodeMPLSStack(d.Labels...), nil +} + +func (d *MPLSDestination) String() string { + s := make([]string, 0, len(d.Labels)) + for _, l := range d.Labels { + s = append(s, fmt.Sprintf("%d", l)) + } + return strings.Join(s, "/") +} + +type MPLSEncap struct { + Labels []int +} + +func (e *MPLSEncap) Type() int { + return nl.LWTUNNEL_ENCAP_MPLS +} + +func (e *MPLSEncap) Decode(buf []byte) error { + if len(buf) < 4 { + return fmt.Errorf("Lack of bytes") + } + native := nl.NativeEndian() + l := native.Uint16(buf) + if len(buf) < int(l) { + return fmt.Errorf("Lack of bytes") + } + buf = buf[:l] + typ := native.Uint16(buf[2:]) + if typ != nl.MPLS_IPTUNNEL_DST { + return fmt.Errorf("Unknown MPLS Encap Type: %d", typ) + } + e.Labels = nl.DecodeMPLSStack(buf[4:]) + return nil +} + +func (e *MPLSEncap) Encode() ([]byte, error) { + s := nl.EncodeMPLSStack(e.Labels...) + native := nl.NativeEndian() + hdr := make([]byte, 4) + native.PutUint16(hdr, uint16(len(s)+4)) + native.PutUint16(hdr[2:], nl.MPLS_IPTUNNEL_DST) + return append(hdr, s...), nil +} + +func (e *MPLSEncap) String() string { + s := make([]string, 0, len(e.Labels)) + for _, l := range e.Labels { + s = append(s, fmt.Sprintf("%d", l)) + } + return strings.Join(s, "/") +} + +// RouteAdd will add a route to the system. +// Equivalent to: `ip route add $route` +func RouteAdd(route *Route) error { + return pkgHandle.RouteAdd(route) +} + +// RouteAdd will add a route to the system. +// Equivalent to: `ip route add $route` +func (h *Handle) RouteAdd(route *Route) error { + flags := syscall.NLM_F_CREATE | syscall.NLM_F_EXCL | syscall.NLM_F_ACK + req := h.newNetlinkRequest(syscall.RTM_NEWROUTE, flags) + return h.routeHandle(route, req, nl.NewRtMsg()) +} + +// RouteReplace will add a route to the system. +// Equivalent to: `ip route replace $route` +func RouteReplace(route *Route) error { + return pkgHandle.RouteReplace(route) +} + +// RouteReplace will add a route to the system. +// Equivalent to: `ip route replace $route` +func (h *Handle) RouteReplace(route *Route) error { + flags := syscall.NLM_F_CREATE | syscall.NLM_F_REPLACE | syscall.NLM_F_ACK + req := h.newNetlinkRequest(syscall.RTM_NEWROUTE, flags) + return h.routeHandle(route, req, nl.NewRtMsg()) +} + +// RouteDel will delete a route from the system. +// Equivalent to: `ip route del $route` +func RouteDel(route *Route) error { + return pkgHandle.RouteDel(route) +} + +// RouteDel will delete a route from the system. +// Equivalent to: `ip route del $route` +func (h *Handle) RouteDel(route *Route) error { + req := h.newNetlinkRequest(syscall.RTM_DELROUTE, syscall.NLM_F_ACK) + return h.routeHandle(route, req, nl.NewRtDelMsg()) +} + +func (h *Handle) routeHandle(route *Route, req *nl.NetlinkRequest, msg *nl.RtMsg) error { + if (route.Dst == nil || route.Dst.IP == nil) && route.Src == nil && route.Gw == nil && route.MPLSDst == nil { + return fmt.Errorf("one of Dst.IP, Src, or Gw must not be nil") + } + + 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)) + } else if route.MPLSDst != nil { + family = nl.FAMILY_MPLS + msg.Dst_len = uint8(20) + msg.Type = syscall.RTN_UNICAST + rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_DST, nl.EncodeMPLSStack(*route.MPLSDst))) + } + + if route.NewDst != nil { + if family != -1 && family != route.NewDst.Family() { + return fmt.Errorf("new destination and destination are not the same address family") + } + buf, err := route.NewDst.Encode() + if err != nil { + return err + } + rtAttrs = append(rtAttrs, nl.NewRtAttr(nl.RTA_NEWDST, buf)) + } + + if route.Encap != nil { + buf := make([]byte, 2) + native.PutUint16(buf, uint16(route.Encap.Type())) + rtAttrs = append(rtAttrs, nl.NewRtAttr(nl.RTA_ENCAP_TYPE, buf)) + buf, err := route.Encap.Encode() + if err != nil { + return err + } + rtAttrs = append(rtAttrs, nl.NewRtAttr(nl.RTA_ENCAP, buf)) + } + + 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)) + } + + if len(route.MultiPath) > 0 { + buf := []byte{} + for _, nh := range route.MultiPath { + rtnh := &nl.RtNexthop{ + RtNexthop: syscall.RtNexthop{ + Hops: uint8(nh.Hops), + Ifindex: int32(nh.LinkIndex), + Flags: uint8(nh.Flags), + }, + } + children := []nl.NetlinkRequestData{} + if nh.Gw != nil { + gwFamily := nl.GetIPFamily(nh.Gw) + if family != -1 && family != gwFamily { + return fmt.Errorf("gateway, source, and destination ip are not the same IP family") + } + if gwFamily == FAMILY_V4 { + children = append(children, nl.NewRtAttr(syscall.RTA_GATEWAY, []byte(nh.Gw.To4()))) + } else { + children = append(children, nl.NewRtAttr(syscall.RTA_GATEWAY, []byte(nh.Gw.To16()))) + } + } + if nh.NewDst != nil { + if family != -1 && family != nh.NewDst.Family() { + return fmt.Errorf("new destination and destination are not the same address family") + } + buf, err := nh.NewDst.Encode() + if err != nil { + return err + } + children = append(children, nl.NewRtAttr(nl.RTA_NEWDST, buf)) + } + if nh.Encap != nil { + buf := make([]byte, 2) + native.PutUint16(buf, uint16(nh.Encap.Type())) + rtAttrs = append(rtAttrs, nl.NewRtAttr(nl.RTA_ENCAP_TYPE, buf)) + buf, err := nh.Encap.Encode() + if err != nil { + return err + } + children = append(children, nl.NewRtAttr(nl.RTA_ENCAP, buf)) + } + rtnh.Children = children + buf = append(buf, rtnh.Serialize()...) + } + rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_MULTIPATH, buf)) + } + + if route.Table > 0 { + if route.Table >= 256 { + msg.Table = syscall.RT_TABLE_UNSPEC + b := make([]byte, 4) + native.PutUint32(b, uint32(route.Table)) + rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_TABLE, b)) + } else { + msg.Table = uint8(route.Table) + } + } + + if route.Priority > 0 { + b := make([]byte, 4) + native.PutUint32(b, uint32(route.Priority)) + rtAttrs = append(rtAttrs, nl.NewRtAttr(syscall.RTA_PRIORITY, b)) + } + if route.Tos > 0 { + msg.Tos = uint8(route.Tos) + } + if route.Protocol > 0 { + msg.Protocol = uint8(route.Protocol) + } + if route.Type > 0 { + msg.Type = uint8(route.Type) + } + + msg.Flags = uint32(route.Flags) + msg.Scope = uint8(route.Scope) + 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 +} + +// 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) { + return pkgHandle.RouteList(link, family) +} + +// 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 (h *Handle) RouteList(link Link, family int) ([]Route, error) { + var routeFilter *Route + if link != nil { + routeFilter = &Route{ + LinkIndex: link.Attrs().Index, + } + } + return h.RouteListFiltered(family, routeFilter, RT_FILTER_OIF) +} + +// RouteListFiltered gets a list of routes in the system filtered with specified rules. +// All rules must be defined in RouteFilter struct +func RouteListFiltered(family int, filter *Route, filterMask uint64) ([]Route, error) { + return pkgHandle.RouteListFiltered(family, filter, filterMask) +} + +// RouteListFiltered gets a list of routes in the system filtered with specified rules. +// All rules must be defined in RouteFilter struct +func (h *Handle) RouteListFiltered(family int, filter *Route, filterMask uint64) ([]Route, error) { + req := h.newNetlinkRequest(syscall.RTM_GETROUTE, syscall.NLM_F_DUMP) + infmsg := nl.NewIfInfomsg(family) + req.AddData(infmsg) + + msgs, err := req.Execute(syscall.NETLINK_ROUTE, syscall.RTM_NEWROUTE) + if err != nil { + return nil, err + } + + 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 { + if filter == nil || filter != nil && filterMask&RT_FILTER_TABLE == 0 { + // Ignore non-main tables + continue + } + } + route, err := deserializeRoute(m) + if err != nil { + return nil, err + } + if filter != nil { + switch { + case filterMask&RT_FILTER_TABLE != 0 && filter.Table != syscall.RT_TABLE_UNSPEC && route.Table != filter.Table: + continue + case filterMask&RT_FILTER_PROTOCOL != 0 && route.Protocol != filter.Protocol: + continue + case filterMask&RT_FILTER_SCOPE != 0 && route.Scope != filter.Scope: + continue + case filterMask&RT_FILTER_TYPE != 0 && route.Type != filter.Type: + continue + case filterMask&RT_FILTER_TOS != 0 && route.Tos != filter.Tos: + continue + case filterMask&RT_FILTER_OIF != 0 && route.LinkIndex != filter.LinkIndex: + continue + case filterMask&RT_FILTER_IIF != 0 && route.ILinkIndex != filter.ILinkIndex: + continue + case filterMask&RT_FILTER_GW != 0 && !route.Gw.Equal(filter.Gw): + continue + case filterMask&RT_FILTER_SRC != 0 && !route.Src.Equal(filter.Src): + continue + case filterMask&RT_FILTER_DST != 0: + if filter.MPLSDst == nil || route.MPLSDst == nil || (*filter.MPLSDst) != (*route.MPLSDst) { + if filter.Dst == nil { + if route.Dst != nil { + continue + } + } else { + if route.Dst == nil { + continue + } + aMaskLen, aMaskBits := route.Dst.Mask.Size() + bMaskLen, bMaskBits := filter.Dst.Mask.Size() + if !(route.Dst.IP.Equal(filter.Dst.IP) && aMaskLen == bMaskLen && aMaskBits == bMaskBits) { + continue + } + } + } + } + } + res = append(res, route) + } + return res, 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() + var encap, encapType syscall.NetlinkRouteAttr + 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: + if msg.Family == nl.FAMILY_MPLS { + stack := nl.DecodeMPLSStack(attr.Value) + if len(stack) == 0 || len(stack) > 1 { + return route, fmt.Errorf("invalid MPLS RTA_DST") + } + route.MPLSDst = &stack[0] + } else { + 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])) + case syscall.RTA_MULTIPATH: + parseRtNexthop := func(value []byte) (*NexthopInfo, []byte, error) { + if len(value) < syscall.SizeofRtNexthop { + return nil, nil, fmt.Errorf("Lack of bytes") + } + nh := nl.DeserializeRtNexthop(value) + if len(value) < int(nh.RtNexthop.Len) { + return nil, nil, fmt.Errorf("Lack of bytes") + } + info := &NexthopInfo{ + LinkIndex: int(nh.RtNexthop.Ifindex), + Hops: int(nh.RtNexthop.Hops), + Flags: int(nh.RtNexthop.Flags), + } + attrs, err := nl.ParseRouteAttr(value[syscall.SizeofRtNexthop:int(nh.RtNexthop.Len)]) + if err != nil { + return nil, nil, err + } + var encap, encapType syscall.NetlinkRouteAttr + for _, attr := range attrs { + switch attr.Attr.Type { + case syscall.RTA_GATEWAY: + info.Gw = net.IP(attr.Value) + case nl.RTA_NEWDST: + var d Destination + switch msg.Family { + case nl.FAMILY_MPLS: + d = &MPLSDestination{} + } + if err := d.Decode(attr.Value); err != nil { + return nil, nil, err + } + info.NewDst = d + case nl.RTA_ENCAP_TYPE: + encapType = attr + case nl.RTA_ENCAP: + encap = attr + } + } + + if len(encap.Value) != 0 && len(encapType.Value) != 0 { + typ := int(native.Uint16(encapType.Value[0:2])) + var e Encap + switch typ { + case nl.LWTUNNEL_ENCAP_MPLS: + e = &MPLSEncap{} + if err := e.Decode(encap.Value); err != nil { + return nil, nil, err + } + } + info.Encap = e + } + + return info, value[int(nh.RtNexthop.Len):], nil + } + rest := attr.Value + for len(rest) > 0 { + info, buf, err := parseRtNexthop(rest) + if err != nil { + return route, err + } + route.MultiPath = append(route.MultiPath, info) + rest = buf + } + case nl.RTA_NEWDST: + var d Destination + switch msg.Family { + case nl.FAMILY_MPLS: + d = &MPLSDestination{} + } + if err := d.Decode(attr.Value); err != nil { + return route, err + } + route.NewDst = d + case nl.RTA_ENCAP_TYPE: + encapType = attr + case nl.RTA_ENCAP: + encap = attr + } + } + + if len(encap.Value) != 0 && len(encapType.Value) != 0 { + typ := int(native.Uint16(encapType.Value[0:2])) + var e Encap + switch typ { + case nl.LWTUNNEL_ENCAP_MPLS: + e = &MPLSEncap{} + if err := e.Decode(encap.Value); err != nil { + return route, err + } + } + route.Encap = e + } + + return route, nil +} + +// RouteGet gets a route to a specific destination from the host system. +// Equivalent to: 'ip route get'. +func RouteGet(destination net.IP) ([]Route, error) { + return pkgHandle.RouteGet(destination) +} + +// RouteGet gets a route to a specific destination from the host system. +// Equivalent to: 'ip route get'. +func (h *Handle) RouteGet(destination net.IP) ([]Route, error) { + req := h.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 + } + + var res []Route + for _, m := range msgs { + route, err := deserializeRoute(m) + if err != nil { + return nil, err + } + res = append(res, route) + } + return res, nil + +} + +// RouteSubscribe takes a chan down which notifications will be sent +// when routes are added or deleted. Close the 'done' chan to stop subscription. +func RouteSubscribe(ch chan<- RouteUpdate, done <-chan struct{}) error { + return routeSubscribeAt(netns.None(), netns.None(), ch, done) +} + +// RouteSubscribeAt works like RouteSubscribe plus it allows the caller +// to choose the network namespace in which to subscribe (ns). +func RouteSubscribeAt(ns netns.NsHandle, ch chan<- RouteUpdate, done <-chan struct{}) error { + return routeSubscribeAt(ns, netns.None(), ch, done) +} + +func routeSubscribeAt(newNs, curNs netns.NsHandle, ch chan<- RouteUpdate, done <-chan struct{}) error { + s, err := nl.SubscribeAt(newNs, curNs, syscall.NETLINK_ROUTE, syscall.RTNLGRP_IPV4_ROUTE, syscall.RTNLGRP_IPV6_ROUTE) + if err != nil { + return err + } + if done != nil { + go func() { + <-done + s.Close() + }() + } + go func() { + defer close(ch) + for { + msgs, err := s.Receive() + if err != nil { + return + } + for _, m := range msgs { + route, err := deserializeRoute(m.Data) + if err != nil { + return + } + ch <- RouteUpdate{Type: m.Header.Type, Route: route} + } + } + }() + + return nil +} |