package netlink
import (
"bytes"
"encoding/binary"
"fmt"
"net"
"strconv"
"strings"
"syscall"
"github.com/vishvananda/netlink/nl"
"github.com/vishvananda/netns"
"golang.org/x/sys/unix"
)
// RtAttr is shared so it is in netlink_linux.go
const (
SCOPE_UNIVERSE Scope = unix.RT_SCOPE_UNIVERSE
SCOPE_SITE Scope = unix.RT_SCOPE_SITE
SCOPE_LINK Scope = unix.RT_SCOPE_LINK
SCOPE_HOST Scope = unix.RT_SCOPE_HOST
SCOPE_NOWHERE Scope = unix.RT_SCOPE_NOWHERE
)
func (s Scope) String() string {
switch s {
case SCOPE_UNIVERSE:
return "universe"
case SCOPE_SITE:
return "site"
case SCOPE_LINK:
return "link"
case SCOPE_HOST:
return "host"
case SCOPE_NOWHERE:
return "nowhere"
default:
return "unknown"
}
}
const (
FLAG_ONLINK NextHopFlag = unix.RTNH_F_ONLINK
FLAG_PERVASIVE NextHopFlag = unix.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, "/")
}
func (d *MPLSDestination) Equal(x Destination) bool {
o, ok := x.(*MPLSDestination)
if !ok {
return false
}
if d == nil && o == nil {
return true
}
if d == nil || o == nil {
return false
}
if d.Labels == nil && o.Labels == nil {
return true
}
if d.Labels == nil || o.Labels == nil {
return false
}
if len(d.Labels) != len(o.Labels) {
return false
}
for i := range d.Labels {
if d.Labels[i] != o.Labels[i] {
return false
}
}
return true
}
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")
}
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...)
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, "/")
}
func (e *MPLSEncap) Equal(x Encap) bool {
o, ok := x.(*MPLSEncap)
if !ok {
return false
}
if e == nil && o == nil {
return true
}
if e == nil || o == nil {
return false
}
if e.Labels == nil && o.Labels == nil {
return true
}
if e.Labels == nil || o.Labels == nil {
return false
}
if len(e.Labels) != len(o.Labels) {
return false
}
for i := range e.Labels {
if e.Labels[i] != o.Labels[i] {
return false
}
}
return true
}
// SEG6 definitions
type SEG6Encap struct {
Mode int
Segments []net.IP
}
func (e *SEG6Encap) Type() int {
return nl.LWTUNNEL_ENCAP_SEG6
}
func (e *SEG6Encap) Decode(buf []byte) error {
if len(buf) < 4 {
return fmt.Errorf("lack of bytes")
}
// Get Length(l) & Type(typ) : 2 + 2 bytes
l := native.Uint16(buf)
if len(buf) < int(l) {
return fmt.Errorf("lack of bytes")
}
buf = buf[:l] // make sure buf size upper limit is Length
typ := native.Uint16(buf[2:])
// LWTUNNEL_ENCAP_SEG6 has only one attr type SEG6_IPTUNNEL_SRH
if typ != nl.SEG6_IPTUNNEL_SRH {
return fmt.Errorf("unknown SEG6 Type: %d", typ)
}
var err error
e.Mode, e.Segments, err = nl.DecodeSEG6Encap(buf[4:])
return err
}
func (e *SEG6Encap) Encode() ([]byte, error) {
s, err := nl.EncodeSEG6Encap(e.Mode, e.Segments)
hdr := make([]byte, 4)
native.PutUint16(hdr, uint16(len(s)+4))
native.PutUint16(hdr[2:], nl.SEG6_IPTUNNEL_SRH)
return append(hdr, s...), err
}
func (e *SEG6Encap) String() string {
segs := make([]string, 0, len(e.Segments))
// append segment backwards (from n to 0) since seg#0 is the last segment.
for i := len(e.Segments); i > 0; i-- {
segs = append(segs, e.Segments[i-1].String())
}
str := fmt.Sprintf("mode %s segs %d [ %s ]", nl.SEG6EncapModeString(e.Mode),
len(e.Segments), strings.Join(segs, " "))
return str
}
func (e *SEG6Encap) Equal(x Encap) bool {
o, ok := x.(*SEG6Encap)
if !ok {
return false
}
if e == o {
return true
}
if e == nil || o == nil {
return false
}
if e.Mode != o.Mode {
return false
}
if len(e.Segments) != len(o.Segments) {
return false
}
for i := range e.Segments {
if !e.Segments[i].Equal(o.Segments[i]) {
return false
}
}
return true
}
// SEG6LocalEncap definitions
type SEG6LocalEncap struct {
Flags [nl.SEG6_LOCAL_MAX]bool
Action int
Segments []net.IP // from SRH in seg6_local_lwt
Table int // table id for End.T and End.DT6
InAddr net.IP
In6Addr net.IP
Iif int
Oif int
bpf bpfObj
}
func (e *SEG6LocalEncap) SetProg(progFd int, progName string) error {
if progFd <= 0 {
return fmt.Errorf("seg6local bpf SetProg: invalid fd")
}
e.bpf.progFd = progFd
e.bpf.progName = progName
return nil
}
func (e *SEG6LocalEncap) Type() int {
return nl.LWTUNNEL_ENCAP_SEG6_LOCAL
}
func (e *SEG6LocalEncap) Decode(buf []byte) error {
attrs, err := nl.ParseRouteAttr(buf)
if err != nil {
return err
}
for _, attr := range attrs {
switch attr.Attr.Type {
case nl.SEG6_LOCAL_ACTION:
e.Action = int(native.Uint32(attr.Value[0:4]))
e.Flags[nl.SEG6_LOCAL_ACTION] = true
case nl.SEG6_LOCAL_SRH:
e.Segments, err = nl.DecodeSEG6Srh(attr.Value[:])
e.Flags[nl.SEG6_LOCAL_SRH] = true
case nl.SEG6_LOCAL_TABLE:
e.Table = int(native.Uint32(attr.Value[0:4]))
e.Flags[nl.SEG6_LOCAL_TABLE] = true
case nl.SEG6_LOCAL_NH4:
e.InAddr = net.IP(attr.Value[0:4])
e.Flags[nl.SEG6_LOCAL_NH4] = true
case nl.SEG6_LOCAL_NH6:
e.In6Addr = net.IP(attr.Value[0:16])
e.Flags[nl.SEG6_LOCAL_NH6] = true
case nl.SEG6_LOCAL_IIF:
e.Iif = int(native.Uint32(attr.Value[0:4]))
e.Flags[nl.SEG6_LOCAL_IIF] = true
case nl.SEG6_LOCAL_OIF:
e.Oif = int(native.Uint32(attr.Value[0:4]))
e.Flags[nl.SEG6_LOCAL_OIF] = true
case nl.SEG6_LOCAL_BPF:
var bpfAttrs []syscall.NetlinkRouteAttr
bpfAttrs, err = nl.ParseRouteAttr(attr.Value)
bpfobj := bpfObj{}
for _, bpfAttr := range bpfAttrs {
switch bpfAttr.Attr.Type {
case nl.LWT_BPF_PROG_FD:
bpfobj.progFd = int(native.Uint32(bpfAttr.Value))
case nl.LWT_BPF_PROG_NAME:
bpfobj.progName = string(bpfAttr.Value)
default:
err = fmt.Errorf("seg6local bpf decode: unknown attribute: Type %d", bpfAttr.Attr)
}
}
e.bpf = bpfobj
e.Flags[nl.SEG6_LOCAL_BPF] = true
}
}
return err
}
func (e *SEG6LocalEncap) Encode() ([]byte, error) {
var err error
res := make([]byte, 8)
native.PutUint16(res, 8) // length
native.PutUint16(res[2:], nl.SEG6_LOCAL_ACTION)
native.PutUint32(res[4:], uint32(e.Action))
if e.Flags[nl.SEG6_LOCAL_SRH] {
srh, err := nl.EncodeSEG6Srh(e.Segments)
if err != nil {
return nil, err
}
attr := make([]byte, 4)
native.PutUint16(attr, uint16(len(srh)+4))
native.PutUint16(attr[2:], nl.SEG6_LOCAL_SRH)
attr = append(attr, srh...)
res = append(res, attr...)
}
if e.Flags[nl.SEG6_LOCAL_TABLE] {
attr := make([]byte, 8)
native.PutUint16(attr, 8)
native.PutUint16(attr[2:], nl.SEG6_LOCAL_TABLE)
native.PutUint32(attr[4:], uint32(e.Table))
res = append(res, attr...)
}
if e.Flags[nl.SEG6_LOCAL_NH4] {
attr := make([]byte, 4)
native.PutUint16(attr, 8)
native.PutUint16(attr[2:], nl.SEG6_LOCAL_NH4)
ipv4 := e.InAddr.To4()
if ipv4 == nil {
err = fmt.Errorf("SEG6_LOCAL_NH4 has invalid IPv4 address")
return nil, err
}
attr = append(attr, ipv4...)
res = append(res, attr...)
}
if e.Flags[nl.SEG6_LOCAL_NH6] {
attr := make([]byte, 4)
native.PutUint16(attr, 20)
native.PutUint16(attr[2:], nl.SEG6_LOCAL_NH6)
attr = append(attr, e.In6Addr...)
res = append(res, attr...)
}
if e.Flags[nl.SEG6_LOCAL_IIF] {
attr := make([]byte, 8)
native.PutUint16(attr, 8)
native.PutUint16(attr[2:], nl.SEG6_LOCAL_IIF)
native.PutUint32(attr[4:], uint32(e.Iif))
res = append(res, attr...)
}
if e.Flags[nl.SEG6_LOCAL_OIF] {
attr := make([]byte, 8)
native.PutUint16(attr, 8)
native.PutUint16(attr[2:], nl.SEG6_LOCAL_OIF)
native.PutUint32(attr[4:], uint32(e.Oif))
res = append(res, attr...)
}
if e.Flags[nl.SEG6_LOCAL_BPF] {
attr := nl.NewRtAttr(nl.SEG6_LOCAL_BPF, []byte{})
if e.bpf.progFd != 0 {
attr.AddRtAttr(nl.LWT_BPF_PROG_FD, nl.Uint32Attr(uint32(e.bpf.progFd)))
}
if e.bpf.progName != "" {
attr.AddRtAttr(nl.LWT_BPF_PROG_NAME, nl.ZeroTerminated(e.bpf.progName))
}
res = append(res, attr.Serialize()...)
}
return res, err
}
func (e *SEG6LocalEncap) String() string {
strs := make([]string, 0, nl.SEG6_LOCAL_MAX)
strs = append(strs, fmt.Sprintf("action %s", nl.SEG6LocalActionString(e.Action)))
if e.Flags[nl.SEG6_LOCAL_TABLE] {
strs = append(strs, fmt.Sprintf("table %d", e.Table))
}
if e.Flags[nl.SEG6_LOCAL_NH4] {
strs = append(strs, fmt.Sprintf("nh4 %s", e.InAddr))
}
if e.Flags[nl.SEG6_LOCAL_NH6] {
strs = append(strs, fmt.Sprintf("nh6 %s", e.In6Addr))
}
if e.Flags[nl.SEG6_LOCAL_IIF] {
link, err := LinkByIndex(e.Iif)
if err != nil {
strs = append(strs, fmt.Sprintf("iif %d", e.Iif))
} else {
strs = append(strs, fmt.Sprintf("iif %s", link.Attrs().Name))
}
}
if e.Flags[nl.SEG6_LOCAL_OIF] {
link, err := LinkByIndex(e.Oif)
if err != nil {
strs = append(strs, fmt.Sprintf("oif %d", e.Oif))
} else {
strs = append(strs, fmt.Sprintf("oif %s", link.Attrs().Name))
}
}
if e.Flags[nl.SEG6_LOCAL_SRH] {
segs := make([]string, 0, len(e.Segments))
// append segment backwards (from n to 0) since seg#0 is the last segment.
for i := len(e.Segments); i > 0; i-- {
segs = append(segs, e.Segments[i-1].String())
}
strs = append(strs, fmt.Sprintf("segs %d [ %s ]", len(e.Segments), strings.Join(segs, " ")))
}
if e.Flags[nl.SEG6_LOCAL_BPF] {
strs = append(strs, fmt.Sprintf("bpf %s[%d]", e.bpf.progName, e.bpf.progFd))
}
return strings.Join(strs, " ")
}
func (e *SEG6LocalEncap) Equal(x Encap) bool {
o, ok := x.(*SEG6LocalEncap)
if !ok {
return false
}
if e == o {
return true
}
if e == nil || o == nil {
return false
}
// compare all arrays first
for i := range e.Flags {
if e.Flags[i] != o.Flags[i] {
return false
}
}
if len(e.Segments) != len(o.Segments) {
return false
}
for i := range e.Segments {
if !e.Segments[i].Equal(o.Segments[i]) {
return false
}
}
// compare values
if !e.InAddr.Equal(o.InAddr) || !e.In6Addr.Equal(o.In6Addr) {
return false
}
if e.Action != o.Action || e.Table != o.Table || e.Iif != o.Iif || e.Oif != o.Oif || e.bpf != o.bpf {
return false
}
return true
}
// Encap BPF definitions
type bpfObj struct {
progFd int
progName string
}
type BpfEncap struct {
progs [nl.LWT_BPF_MAX]bpfObj
headroom int
}
// SetProg adds a bpf function to the route via netlink RTA_ENCAP. The fd must be a bpf
// program loaded with bpf(type=BPF_PROG_TYPE_LWT_*) matching the direction the program should
// be applied to (LWT_BPF_IN, LWT_BPF_OUT, LWT_BPF_XMIT).
func (e *BpfEncap) SetProg(mode, progFd int, progName string) error {
if progFd <= 0 {
return fmt.Errorf("lwt bpf SetProg: invalid fd")
}
if mode <= nl.LWT_BPF_UNSPEC || mode >= nl.LWT_BPF_XMIT_HEADROOM {
return fmt.Errorf("lwt bpf SetProg:invalid mode")
}
e.progs[mode].progFd = progFd
e.progs[mode].progName = fmt.Sprintf("%s[fd:%d]", progName, progFd)
return nil
}
// SetXmitHeadroom sets the xmit headroom (LWT_BPF_MAX_HEADROOM) via netlink RTA_ENCAP.
// maximum headroom is LWT_BPF_MAX_HEADROOM
func (e *BpfEncap) SetXmitHeadroom(headroom int) error {
if headroom > nl.LWT_BPF_MAX_HEADROOM || headroom < 0 {
return fmt.Errorf("invalid headroom size. range is 0 - %d", nl.LWT_BPF_MAX_HEADROOM)
}
e.headroom = headroom
return nil
}
func (e *BpfEncap) Type() int {
return nl.LWTUNNEL_ENCAP_BPF
}
func (e *BpfEncap) Decode(buf []byte) error {
if len(buf) < 4 {
return fmt.Errorf("lwt bpf decode: lack of bytes")
}
native := nl.NativeEndian()
attrs, err := nl.ParseRouteAttr(buf)
if err != nil {
return fmt.Errorf("lwt bpf decode: failed parsing attribute. err: %v", err)
}
for _, attr := range attrs {
if int(attr.Attr.Type) < 1 {
// nl.LWT_BPF_UNSPEC
continue
}
if int(attr.Attr.Type) > nl.LWT_BPF_MAX {
return fmt.Errorf("lwt bpf decode: received unknown attribute type: %d", attr.Attr.Type)
}
switch int(attr.Attr.Type) {
case nl.LWT_BPF_MAX_HEADROOM:
e.headroom = int(native.Uint32(attr.Value))
default:
bpfO := bpfObj{}
parsedAttrs, err := nl.ParseRouteAttr(attr.Value)
if err != nil {
return fmt.Errorf("lwt bpf decode: failed parsing route attribute")
}
for _, parsedAttr := range parsedAttrs {
switch int(parsedAttr.Attr.Type) {
case nl.LWT_BPF_PROG_FD:
bpfO.progFd = int(native.Uint32(parsedAttr.Value))
case nl.LWT_BPF_PROG_NAME:
bpfO.progName = string(parsedAttr.Value)
default:
return fmt.Errorf("lwt bpf decode: received unknown attribute: type: %d, len: %d", parsedAttr.Attr.Type, parsedAttr.Attr.Len)
}
}
e.progs[attr.Attr.Type] = bpfO
}
}
return nil
}
func (e *BpfEncap) Encode() ([]byte, error) {
buf := make([]byte, 0)
native = nl.NativeEndian()
for index, attr := range e.progs {
nlMsg := nl.NewRtAttr(index, []byte{})
if attr.progFd != 0 {
nlMsg.AddRtAttr(nl.LWT_BPF_PROG_FD, nl.Uint32Attr(uint32(attr.progFd)))
}
if attr.progName != "" {
nlMsg.AddRtAttr(nl.LWT_BPF_PROG_NAME, nl.ZeroTerminated(attr.progName))
}
if nlMsg.Len() > 4 {
buf = append(buf, nlMsg.Serialize()...)
}
}
if len(buf) <= 4 {
return nil, fmt.Errorf("lwt bpf encode: bpf obj definitions returned empty buffer")
}
if e.headroom > 0 {
hRoom := nl.NewRtAttr(nl.LWT_BPF_XMIT_HEADROOM, nl.Uint32Attr(uint32(e.headroom)))
buf = append(buf, hRoom.Serialize()...)
}
return buf, nil
}
func (e *BpfEncap) String() string {
progs := make([]string, 0)
for index, obj := range e.progs {
empty := bpfObj{}
switch index {
case nl.LWT_BPF_IN:
if obj != empty {
progs = append(progs, fmt.Sprintf("in: %s", obj.progName))
}
case nl.LWT_BPF_OUT:
if obj != empty {
progs = append(progs, fmt.Sprintf("out: %s", obj.progName))
}
case nl.LWT_BPF_XMIT:
if obj != empty {
progs = append(progs, fmt.Sprintf("xmit: %s", obj.progName))
}
}
}
if e.headroom > 0 {
progs = append(progs, fmt.Sprintf("xmit headroom: %d", e.headroom))
}
return strings.Join(progs, " ")
}
func (e *BpfEncap) Equal(x Encap) bool {
o, ok := x.(*BpfEncap)
if !ok {
return false
}
if e.headroom != o.headroom {
return false
}
for i := range o.progs {
if o.progs[i] != e.progs[i] {
return false
}
}
return true
}
// IP6tnlEncap definition
type IP6tnlEncap struct {
ID uint64
Dst net.IP
Src net.IP
Hoplimit uint8
TC uint8
Flags uint16
}
func (e *IP6tnlEncap) Type() int {
return nl.LWTUNNEL_ENCAP_IP6
}
func (e *IP6tnlEncap) Decode(buf []byte) error {
attrs, err := nl.ParseRouteAttr(buf)
if err != nil {
return err
}
for _, attr := range attrs {
switch attr.Attr.Type {
case nl.LWTUNNEL_IP6_ID:
e.ID = uint64(native.Uint64(attr.Value[0:4]))
case nl.LWTUNNEL_IP6_DST:
e.Dst = net.IP(attr.Value[:])
case nl.LWTUNNEL_IP6_SRC:
e.Src = net.IP(attr.Value[:])
case nl.LWTUNNEL_IP6_HOPLIMIT:
e.Hoplimit = attr.Value[0]
case nl.LWTUNNEL_IP6_TC:
// e.TC = attr.Value[0]
err = fmt.Errorf("decoding TC in IP6tnlEncap is not supported")
case nl.LWTUNNEL_IP6_FLAGS:
// e.Flags = uint16(native.Uint16(attr.Value[0:2]))
err = fmt.Errorf("decoding FLAG in IP6tnlEncap is not supported")
case nl.LWTUNNEL_IP6_PAD:
err = fmt.Errorf("decoding PAD in IP6tnlEncap is not supported")
case nl.LWTUNNEL_IP6_OPTS:
err = fmt.Errorf("decoding OPTS in IP6tnlEncap is not supported")
}
}
return err
}
func (e *IP6tnlEncap) Encode() ([]byte, error) {
final := []byte{}
resID := make([]byte, 12)
native.PutUint16(resID, 12) // 2+2+8
native.PutUint16(resID[2:], nl.LWTUNNEL_IP6_ID)
native.PutUint64(resID[4:], 0)
final = append(final, resID...)
resDst := make([]byte, 4)
native.PutUint16(resDst, 20) // 2+2+16
native.PutUint16(resDst[2:], nl.LWTUNNEL_IP6_DST)
resDst = append(resDst, e.Dst...)
final = append(final, resDst...)
resSrc := make([]byte, 4)
native.PutUint16(resSrc, 20)
native.PutUint16(resSrc[2:], nl.LWTUNNEL_IP6_SRC)
resSrc = append(resSrc, e.Src...)
final = append(final, resSrc...)
// resTc := make([]byte, 5)
// native.PutUint16(resTc, 5)
// native.PutUint16(resTc[2:], nl.LWTUNNEL_IP6_TC)
// resTc[4] = e.TC
// final = append(final,resTc...)
resHops := make([]byte, 5)
native.PutUint16(resHops, 5)
native.PutUint16(resHops[2:], nl.LWTUNNEL_IP6_HOPLIMIT)
resHops[4] = e.Hoplimit
final = append(final, resHops...)
// resFlags := make([]byte, 6)
// native.PutUint16(resFlags, 6)
// native.PutUint16(resFlags[2:], nl.LWTUNNEL_IP6_FLAGS)
// native.PutUint16(resFlags[4:], e.Flags)
// final = append(final,resFlags...)
return final, nil
}
func (e *IP6tnlEncap) String() string {
return fmt.Sprintf("id %d src %s dst %s hoplimit %d tc %d flags 0x%.4x", e.ID, e.Src, e.Dst, e.Hoplimit, e.TC, e.Flags)
}
func (e *IP6tnlEncap) Equal(x Encap) bool {
o, ok := x.(*IP6tnlEncap)
if !ok {
return false
}
if e.ID != o.ID || e.Flags != o.Flags || e.Hoplimit != o.Hoplimit || e.Src.Equal(o.Src) || e.Dst.Equal(o.Dst) || e.TC != o.TC {
return false
}
return true
}
type Via struct {
AddrFamily int
Addr net.IP
}
func (v *Via) Equal(x Destination) bool {
o, ok := x.(*Via)
if !ok {
return false
}
if v.AddrFamily == x.Family() && v.Addr.Equal(o.Addr) {
return true
}
return false
}
func (v *Via) String() string {
return fmt.Sprintf("Family: %d, Address: %s", v.AddrFamily, v.Addr.String())
}
func (v *Via) Family() int {
return v.AddrFamily
}
func (v *Via) Encode() ([]byte, error) {
buf := &bytes.Buffer{}
err := binary.Write(buf, native, uint16(v.AddrFamily))
if err != nil {
return nil, err
}
err = binary.Write(buf, native, v.Addr)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
func (v *Via) Decode(b []byte) error {
if len(b) < 6 {
return fmt.Errorf("decoding failed: buffer too small (%d bytes)", len(b))
}
v.AddrFamily = int(native.Uint16(b[0:2]))
if v.AddrFamily == nl.FAMILY_V4 {
v.Addr = net.IP(b[2:6])
return nil
} else if v.AddrFamily == nl.FAMILY_V6 {
if len(b) < 18 {
return fmt.Errorf("decoding failed: buffer too small (%d bytes)", len(b))
}
v.Addr = net.IP(b[2:])
return nil
}
return fmt.Errorf("decoding failed: address family %d unknown", v.AddrFamily)
}
// 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 := unix.NLM_F_CREATE | unix.NLM_F_EXCL | unix.NLM_F_ACK
req := h.newNetlinkRequest(unix.RTM_NEWROUTE, flags)
_, err := h.routeHandle(route, req, nl.NewRtMsg())
return err
}
// RouteAppend will append a route to the system.
// Equivalent to: `ip route append $route`
func RouteAppend(route *Route) error {
return pkgHandle.RouteAppend(route)
}
// RouteAppend will append a route to the system.
// Equivalent to: `ip route append $route`
func (h *Handle) RouteAppend(route *Route) error {
flags := unix.NLM_F_CREATE | unix.NLM_F_APPEND | unix.NLM_F_ACK
req := h.newNetlinkRequest(unix.RTM_NEWROUTE, flags)
_, err := h.routeHandle(route, req, nl.NewRtMsg())
return err
}
// RouteAddEcmp will add a route to the system.
func RouteAddEcmp(route *Route) error {
return pkgHandle.RouteAddEcmp(route)
}
// RouteAddEcmp will add a route to the system.
func (h *Handle) RouteAddEcmp(route *Route) error {
flags := unix.NLM_F_CREATE | unix.NLM_F_ACK
req := h.newNetlinkRequest(unix.RTM_NEWROUTE, flags)
_, err := h.routeHandle(route, req, nl.NewRtMsg())
return err
}
// RouteChange will change an existing route in the system.
// Equivalent to: `ip route change $route`
func RouteChange(route *Route) error {
return pkgHandle.RouteChange(route)
}
// RouteChange will change an existing route in the system.
// Equivalent to: `ip route change $route`
func (h *Handle) RouteChange(route *Route) error {
flags := unix.NLM_F_REPLACE | unix.NLM_F_ACK
req := h.newNetlinkRequest(unix.RTM_NEWROUTE, flags)
_, err := h.routeHandle(route, req, nl.NewRtMsg())
return err
}
// 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 := unix.NLM_F_CREATE | unix.NLM_F_REPLACE | unix.NLM_F_ACK
req := h.newNetlinkRequest(unix.RTM_NEWROUTE, flags)
_, err := h.routeHandle(route, req, nl.NewRtMsg())
return err
}
// 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(unix.RTM_DELROUTE, unix.NLM_F_ACK)
_, err := h.routeHandle(route, req, nl.NewRtDelMsg())
return err
}
func (h *Handle) routeHandle(route *Route, req *nl.NetlinkRequest, msg *nl.RtMsg) ([][]byte, error) {
if err := h.prepareRouteReq(route, req, msg); err != nil {
return nil, err
}
return req.Execute(unix.NETLINK_ROUTE, 0)
}
func (h *Handle) routeHandleIter(route *Route, req *nl.NetlinkRequest, msg *nl.RtMsg, f func(msg []byte) bool) error {
if err := h.prepareRouteReq(route, req, msg); err != nil {
return err
}
return req.ExecuteIter(unix.NETLINK_ROUTE, 0, f)
}
func (h *Handle) prepareRouteReq(route *Route, req *nl.NetlinkRequest, msg *nl.RtMsg) error {
if req.NlMsghdr.Type != unix.RTM_GETROUTE && (route.Dst == nil || route.Dst.IP == nil) && route.Src == nil && route.Gw == nil && route.MPLSDst == nil {
return fmt.Errorf("either Dst.IP, Src.IP or Gw must be set")
}
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(unix.RTA_DST, dstData))
} else if route.MPLSDst != nil {
family = nl.FAMILY_MPLS
msg.Dst_len = uint8(20)
msg.Type = unix.RTN_UNICAST
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.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(unix.RTA_NEWDST, buf))
}
if route.Encap != nil {
buf := make([]byte, 2)
native.PutUint16(buf, uint16(route.Encap.Type()))
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.RTA_ENCAP_TYPE, buf))
buf, err := route.Encap.Encode()
if err != nil {
return err
}
switch route.Encap.Type() {
case nl.LWTUNNEL_ENCAP_BPF:
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.RTA_ENCAP|unix.NLA_F_NESTED, buf))
default:
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.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(unix.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(unix.RTA_GATEWAY, gwData))
}
if route.Via != nil {
buf, err := route.Via.Encode()
if err != nil {
return fmt.Errorf("failed to encode RTA_VIA: %v", err)
}
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.RTA_VIA, buf))
}
if len(route.MultiPath) > 0 {
buf := []byte{}
for _, nh := range route.MultiPath {
rtnh := &nl.RtNexthop{
RtNexthop: unix.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(unix.RTA_GATEWAY, []byte(nh.Gw.To4())))
} else {
children = append(children, nl.NewRtAttr(unix.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(unix.RTA_NEWDST, buf))
}
if nh.Encap != nil {
buf := make([]byte, 2)
native.PutUint16(buf, uint16(nh.Encap.Type()))
children = append(children, nl.NewRtAttr(unix.RTA_ENCAP_TYPE, buf))
buf, err := nh.Encap.Encode()
if err != nil {
return err
}
children = append(children, nl.NewRtAttr(unix.RTA_ENCAP, buf))
}
if nh.Via != nil {
buf, err := nh.Via.Encode()
if err != nil {
return err
}
children = append(children, nl.NewRtAttr(unix.RTA_VIA, buf))
}
rtnh.Children = children
buf = append(buf, rtnh.Serialize()...)
}
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.RTA_MULTIPATH, buf))
}
if route.Table > 0 {
if route.Table >= 256 {
msg.Table = unix.RT_TABLE_UNSPEC
b := make([]byte, 4)
native.PutUint32(b, uint32(route.Table))
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.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(unix.RTA_PRIORITY, b))
}
if route.Realm > 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(route.Realm))
rtAttrs = append(rtAttrs, nl.NewRtAttr(unix.RTA_FLOW, 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)
}
var metrics []*nl.RtAttr
if route.MTU > 0 {
b := nl.Uint32Attr(uint32(route.MTU))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_MTU, b))
}
if route.Window > 0 {
b := nl.Uint32Attr(uint32(route.Window))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_WINDOW, b))
}
if route.Rtt > 0 {
b := nl.Uint32Attr(uint32(route.Rtt))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_RTT, b))
}
if route.RttVar > 0 {
b := nl.Uint32Attr(uint32(route.RttVar))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_RTTVAR, b))
}
if route.Ssthresh > 0 {
b := nl.Uint32Attr(uint32(route.Ssthresh))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_SSTHRESH, b))
}
if route.Cwnd > 0 {
b := nl.Uint32Attr(uint32(route.Cwnd))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_CWND, b))
}
if route.AdvMSS > 0 {
b := nl.Uint32Attr(uint32(route.AdvMSS))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_ADVMSS, b))
}
if route.Reordering > 0 {
b := nl.Uint32Attr(uint32(route.Reordering))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_REORDERING, b))
}
if route.Hoplimit > 0 {
b := nl.Uint32Attr(uint32(route.Hoplimit))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_HOPLIMIT, b))
}
if route.InitCwnd > 0 {
b := nl.Uint32Attr(uint32(route.InitCwnd))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_INITCWND, b))
}
if route.Features > 0 {
b := nl.Uint32Attr(uint32(route.Features))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_FEATURES, b))
}
if route.RtoMin > 0 {
b := nl.Uint32Attr(uint32(route.RtoMin))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_RTO_MIN, b))
}
if route.InitRwnd > 0 {
b := nl.Uint32Attr(uint32(route.InitRwnd))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_INITRWND, b))
}
if route.QuickACK > 0 {
b := nl.Uint32Attr(uint32(route.QuickACK))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_QUICKACK, b))
}
if route.Congctl != "" {
b := nl.ZeroTerminated(route.Congctl)
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_CC_ALGO, b))
}
if route.FastOpenNoCookie > 0 {
b := nl.Uint32Attr(uint32(route.FastOpenNoCookie))
metrics = append(metrics, nl.NewRtAttr(unix.RTAX_FASTOPEN_NO_COOKIE, b))
}
if metrics != nil {
attr := nl.NewRtAttr(unix.RTA_METRICS, nil)
for _, metric := range metrics {
attr.AddChild(metric)
}
rtAttrs = append(rtAttrs, attr)
}
msg.Flags = uint32(route.Flags)
msg.Scope = uint8(route.Scope)
// only overwrite family if it was not set in msg
if msg.Family == 0 {
msg.Family = uint8(family)
}
req.AddData(msg)
for _, attr := range rtAttrs {
req.AddData(attr)
}
if (req.NlMsghdr.Type != unix.RTM_GETROUTE) || (req.NlMsghdr.Type == unix.RTM_GETROUTE && route.LinkIndex > 0) {
b := make([]byte, 4)
native.PutUint32(b, uint32(route.LinkIndex))
req.AddData(nl.NewRtAttr(unix.RTA_OIF, b))
}
return nil
}
// 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) {
routeFilter := &Route{}
if link != nil {
routeFilter.LinkIndex = link.Attrs().Index
return h.RouteListFiltered(family, routeFilter, RT_FILTER_OIF)
}
return h.RouteListFiltered(family, routeFilter, 0)
}
// 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) {
var res []Route
err := h.RouteListFilteredIter(family, filter, filterMask, func(route Route) (cont bool) {
res = append(res, route)
return true
})
if err != nil {
return nil, err
}
return res, nil
}
// RouteListFilteredIter passes each route that matches the filter to the given iterator func. Iteration continues
// until all routes are loaded or the func returns false.
func RouteListFilteredIter(family int, filter *Route, filterMask uint64, f func(Route) (cont bool)) error {
return pkgHandle.RouteListFilteredIter(family, filter, filterMask, f)
}
func (h *Handle) RouteListFilteredIter(family int, filter *Route, filterMask uint64, f func(Route) (cont bool)) error {
req := h.newNetlinkRequest(unix.RTM_GETROUTE, unix.NLM_F_DUMP)
rtmsg := &nl.RtMsg{}
rtmsg.Family = uint8(family)
var parseErr error
err := h.routeHandleIter(filter, req, rtmsg, func(m []byte) bool {
msg := nl.DeserializeRtMsg(m)
if family != FAMILY_ALL && msg.Family != uint8(family) {
// Ignore routes not matching requested family
return true
}
if msg.Flags&unix.RTM_F_CLONED != 0 {
// Ignore cloned routes
return true
}
if msg.Table != unix.RT_TABLE_MAIN {
if filter == nil || filterMask&RT_FILTER_TABLE == 0 {
// Ignore non-main tables
return true
}
}
route, err := deserializeRoute(m)
if err != nil {
parseErr = err
return false
}
if filter != nil {
switch {
case filterMask&RT_FILTER_TABLE != 0 && filter.Table != unix.RT_TABLE_UNSPEC && route.Table != filter.Table:
return true
case filterMask&RT_FILTER_PROTOCOL != 0 && route.Protocol != filter.Protocol:
return true
case filterMask&RT_FILTER_SCOPE != 0 && route.Scope != filter.Scope:
return true
case filterMask&RT_FILTER_TYPE != 0 && route.Type != filter.Type:
return true
case filterMask&RT_FILTER_TOS != 0 && route.Tos != filter.Tos:
return true
case filterMask&RT_FILTER_REALM != 0 && route.Realm != filter.Realm:
return true
case filterMask&RT_FILTER_OIF != 0 && route.LinkIndex != filter.LinkIndex:
return true
case filterMask&RT_FILTER_IIF != 0 && route.ILinkIndex != filter.ILinkIndex:
return true
case filterMask&RT_FILTER_GW != 0 && !route.Gw.Equal(filter.Gw):
return true
case filterMask&RT_FILTER_SRC != 0 && !route.Src.Equal(filter.Src):
return true
case filterMask&RT_FILTER_DST != 0:
if filter.MPLSDst == nil || route.MPLSDst == nil || (*filter.MPLSDst) != (*route.MPLSDst) {
if filter.Dst == nil {
filter.Dst = genZeroIPNet(family)
}
if !ipNetEqual(route.Dst, filter.Dst) {
return true
}
}
case filterMask&RT_FILTER_HOPLIMIT != 0 && route.Hoplimit != filter.Hoplimit:
return true
}
}
return f(route)
})
if err != nil {
return err
}
if parseErr != nil {
return parseErr
}
return 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: RouteProtocol(int(msg.Protocol)),
Table: int(msg.Table),
Type: int(msg.Type),
Tos: int(msg.Tos),
Flags: int(msg.Flags),
Family: int(msg.Family),
}
var encap, encapType syscall.NetlinkRouteAttr
for _, attr := range attrs {
switch attr.Attr.Type {
case unix.RTA_GATEWAY:
route.Gw = net.IP(attr.Value)
case unix.RTA_PREFSRC:
route.Src = net.IP(attr.Value)
case unix.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 unix.RTA_OIF:
route.LinkIndex = int(native.Uint32(attr.Value[0:4]))
case unix.RTA_IIF:
route.ILinkIndex = int(native.Uint32(attr.Value[0:4]))
case unix.RTA_PRIORITY:
route.Priority = int(native.Uint32(attr.Value[0:4]))
case unix.RTA_FLOW:
route.Realm = int(native.Uint32(attr.Value[0:4]))
case unix.RTA_TABLE:
route.Table = int(native.Uint32(attr.Value[0:4]))
case unix.RTA_MULTIPATH:
parseRtNexthop := func(value []byte) (*NexthopInfo, []byte, error) {
if len(value) < unix.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[unix.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 unix.RTA_GATEWAY:
info.Gw = net.IP(attr.Value)
case unix.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 unix.RTA_ENCAP_TYPE:
encapType = attr
case unix.RTA_ENCAP:
encap = attr
case unix.RTA_VIA:
d := &Via{}
if err := d.Decode(attr.Value); err != nil {
return nil, nil, err
}
info.Via = d
}
}
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 unix.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 unix.RTA_VIA:
v := &Via{}
if err := v.Decode(attr.Value); err != nil {
return route, err
}
route.Via = v
case unix.RTA_ENCAP_TYPE:
encapType = attr
case unix.RTA_ENCAP:
encap = attr
case unix.RTA_METRICS:
metrics, err := nl.ParseRouteAttr(attr.Value)
if err != nil {
return route, err
}
for _, metric := range metrics {
switch metric.Attr.Type {
case unix.RTAX_MTU:
route.MTU = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_WINDOW:
route.Window = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_RTT:
route.Rtt = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_RTTVAR:
route.RttVar = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_SSTHRESH:
route.Ssthresh = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_CWND:
route.Cwnd = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_ADVMSS:
route.AdvMSS = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_REORDERING:
route.Reordering = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_HOPLIMIT:
route.Hoplimit = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_INITCWND:
route.InitCwnd = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_FEATURES:
route.Features = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_RTO_MIN:
route.RtoMin = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_INITRWND:
route.InitRwnd = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_QUICKACK:
route.QuickACK = int(native.Uint32(metric.Value[0:4]))
case unix.RTAX_CC_ALGO:
route.Congctl = nl.BytesToString(metric.Value)
case unix.RTAX_FASTOPEN_NO_COOKIE:
route.FastOpenNoCookie = int(native.Uint32(metric.Value[0:4]))
}
}
}
}
// Same logic to generate "default" dst with iproute2 implementation
if route.Dst == nil {
var addLen int
var ip net.IP
switch msg.Family {
case FAMILY_V4:
addLen = net.IPv4len
ip = net.IPv4zero
case FAMILY_V6:
addLen = net.IPv6len
ip = net.IPv6zero
}
if addLen != 0 {
route.Dst = &net.IPNet{
IP: ip,
Mask: net.CIDRMask(int(msg.Dst_len), 8*addLen),
}
}
}
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
}
case nl.LWTUNNEL_ENCAP_SEG6:
e = &SEG6Encap{}
if err := e.Decode(encap.Value); err != nil {
return route, err
}
case nl.LWTUNNEL_ENCAP_SEG6_LOCAL:
e = &SEG6LocalEncap{}
if err := e.Decode(encap.Value); err != nil {
return route, err
}
case nl.LWTUNNEL_ENCAP_BPF:
e = &BpfEncap{}
if err := e.Decode(encap.Value); err != nil {
return route, err
}
}
route.Encap = e
}
return route, nil
}
// RouteGetOptions contains a set of options to use with
// RouteGetWithOptions
type RouteGetOptions struct {
Iif string
IifIndex int
Oif string
VrfName string
SrcAddr net.IP
UID *uint32
Mark uint32
FIBMatch bool
}
// RouteGetWithOptions gets a route to a specific destination from the host system.
// Equivalent to: 'ip route get <> vrf <VrfName>'.
func RouteGetWithOptions(destination net.IP, options *RouteGetOptions) ([]Route, error) {
return pkgHandle.RouteGetWithOptions(destination, options)
}
// 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)
}
// RouteGetWithOptions gets a route to a specific destination from the host system.
// Equivalent to: 'ip route get <> vrf <VrfName>'.
func (h *Handle) RouteGetWithOptions(destination net.IP, options *RouteGetOptions) ([]Route, error) {
req := h.newNetlinkRequest(unix.RTM_GETROUTE, unix.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
if options != nil && options.SrcAddr != nil {
msg.Src_len = bitlen
}
msg.Flags = unix.RTM_F_LOOKUP_TABLE
if options != nil && options.FIBMatch {
msg.Flags |= unix.RTM_F_FIB_MATCH
}
req.AddData(msg)
rtaDst := nl.NewRtAttr(unix.RTA_DST, destinationData)
req.AddData(rtaDst)
if options != nil {
if options.VrfName != "" {
link, err := h.LinkByName(options.VrfName)
if err != nil {
return nil, err
}
b := make([]byte, 4)
native.PutUint32(b, uint32(link.Attrs().Index))
req.AddData(nl.NewRtAttr(unix.RTA_OIF, b))
}
iifIndex := 0
if len(options.Iif) > 0 {
link, err := h.LinkByName(options.Iif)
if err != nil {
return nil, err
}
iifIndex = link.Attrs().Index
} else if options.IifIndex > 0 {
iifIndex = options.IifIndex
}
if iifIndex > 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(iifIndex))
req.AddData(nl.NewRtAttr(unix.RTA_IIF, b))
}
if len(options.Oif) > 0 {
link, err := h.LinkByName(options.Oif)
if err != nil {
return nil, err
}
b := make([]byte, 4)
native.PutUint32(b, uint32(link.Attrs().Index))
req.AddData(nl.NewRtAttr(unix.RTA_OIF, b))
}
if options.SrcAddr != nil {
var srcAddr []byte
if family == FAMILY_V4 {
srcAddr = options.SrcAddr.To4()
} else {
srcAddr = options.SrcAddr.To16()
}
req.AddData(nl.NewRtAttr(unix.RTA_SRC, srcAddr))
}
if options.UID != nil {
uid := *options.UID
b := make([]byte, 4)
native.PutUint32(b, uid)
req.AddData(nl.NewRtAttr(unix.RTA_UID, b))
}
if options.Mark > 0 {
b := make([]byte, 4)
native.PutUint32(b, options.Mark)
req.AddData(nl.NewRtAttr(unix.RTA_MARK, b))
}
}
msgs, err := req.Execute(unix.NETLINK_ROUTE, unix.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
}
// 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) {
return h.RouteGetWithOptions(destination, 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, nil, false, 0, nil, false)
}
// 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, nil, false, 0, nil, false)
}
// RouteSubscribeOptions contains a set of options to use with
// RouteSubscribeWithOptions.
type RouteSubscribeOptions struct {
Namespace *netns.NsHandle
ErrorCallback func(error)
ListExisting bool
ReceiveBufferSize int
ReceiveBufferForceSize bool
ReceiveTimeout *unix.Timeval
}
// RouteSubscribeWithOptions work like RouteSubscribe but enable to
// provide additional options to modify the behavior. Currently, the
// namespace can be provided as well as an error callback.
func RouteSubscribeWithOptions(ch chan<- RouteUpdate, done <-chan struct{}, options RouteSubscribeOptions) error {
if options.Namespace == nil {
none := netns.None()
options.Namespace = &none
}
return routeSubscribeAt(*options.Namespace, netns.None(), ch, done, options.ErrorCallback, options.ListExisting,
options.ReceiveBufferSize, options.ReceiveTimeout, options.ReceiveBufferForceSize)
}
func routeSubscribeAt(newNs, curNs netns.NsHandle, ch chan<- RouteUpdate, done <-chan struct{}, cberr func(error), listExisting bool,
rcvbuf int, rcvTimeout *unix.Timeval, rcvbufForce bool) error {
s, err := nl.SubscribeAt(newNs, curNs, unix.NETLINK_ROUTE, unix.RTNLGRP_IPV4_ROUTE, unix.RTNLGRP_IPV6_ROUTE)
if err != nil {
return err
}
if rcvTimeout != nil {
if err := s.SetReceiveTimeout(rcvTimeout); err != nil {
return err
}
}
if rcvbuf != 0 {
err = s.SetReceiveBufferSize(rcvbuf, rcvbufForce)
if err != nil {
return err
}
}
if done != nil {
go func() {
<-done
s.Close()
}()
}
if listExisting {
req := pkgHandle.newNetlinkRequest(unix.RTM_GETROUTE,
unix.NLM_F_DUMP)
infmsg := nl.NewIfInfomsg(unix.AF_UNSPEC)
req.AddData(infmsg)
if err := s.Send(req); err != nil {
return err
}
}
go func() {
defer close(ch)
for {
msgs, from, err := s.Receive()
if err != nil {
if cberr != nil {
cberr(fmt.Errorf("Receive failed: %v",
err))
}
return
}
if from.Pid != nl.PidKernel {
if cberr != nil {
cberr(fmt.Errorf("Wrong sender portid %d, expected %d", from.Pid, nl.PidKernel))
}
continue
}
for _, m := range msgs {
if m.Header.Type == unix.NLMSG_DONE {
continue
}
if m.Header.Type == unix.NLMSG_ERROR {
error := int32(native.Uint32(m.Data[0:4]))
if error == 0 {
continue
}
if cberr != nil {
cberr(fmt.Errorf("error message: %v",
syscall.Errno(-error)))
}
continue
}
route, err := deserializeRoute(m.Data)
if err != nil {
if cberr != nil {
cberr(err)
}
continue
}
ch <- RouteUpdate{
Type: m.Header.Type,
NlFlags: m.Header.Flags & (unix.NLM_F_REPLACE | unix.NLM_F_EXCL | unix.NLM_F_CREATE | unix.NLM_F_APPEND),
Route: route,
}
}
}
}()
return nil
}
func (p RouteProtocol) String() string {
switch int(p) {
case unix.RTPROT_BABEL:
return "babel"
case unix.RTPROT_BGP:
return "bgp"
case unix.RTPROT_BIRD:
return "bird"
case unix.RTPROT_BOOT:
return "boot"
case unix.RTPROT_DHCP:
return "dhcp"
case unix.RTPROT_DNROUTED:
return "dnrouted"
case unix.RTPROT_EIGRP:
return "eigrp"
case unix.RTPROT_GATED:
return "gated"
case unix.RTPROT_ISIS:
return "isis"
// case unix.RTPROT_KEEPALIVED:
// return "keepalived"
case unix.RTPROT_KERNEL:
return "kernel"
case unix.RTPROT_MROUTED:
return "mrouted"
case unix.RTPROT_MRT:
return "mrt"
case unix.RTPROT_NTK:
return "ntk"
case unix.RTPROT_OSPF:
return "ospf"
case unix.RTPROT_RA:
return "ra"
case unix.RTPROT_REDIRECT:
return "redirect"
case unix.RTPROT_RIP:
return "rip"
case unix.RTPROT_STATIC:
return "static"
case unix.RTPROT_UNSPEC:
return "unspec"
case unix.RTPROT_XORP:
return "xorp"
case unix.RTPROT_ZEBRA:
return "zebra"
default:
return strconv.Itoa(int(p))
}
}
// genZeroIPNet returns 0.0.0.0/0 or ::/0 for IPv4 or IPv6, otherwise nil
func genZeroIPNet(family int) *net.IPNet {
var addLen int
var ip net.IP
switch family {
case FAMILY_V4:
addLen = net.IPv4len
ip = net.IPv4zero
case FAMILY_V6:
addLen = net.IPv6len
ip = net.IPv6zero
}
if addLen != 0 {
return &net.IPNet{
IP: ip,
Mask: net.CIDRMask(0, 8*addLen),
}
}
return nil
}