// LinkSubscribe takes a chan down which notifications will be sent
// when links change. Close the 'done' chan to stop subscription.
func LinkSubscribe(ch chan<- LinkUpdate, done <-chan struct{}) error {
s, err := nl.Subscribe(syscall.NETLINK_ROUTE, syscall.RTNLGRP_LINK)
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 {
ifmsg := nl.DeserializeIfInfomsg(m.Data)
link, err := linkDeserialize(m.Data)
if err != nil {
return
}
ch <- LinkUpdate{IfInfomsg: *ifmsg, Link: link}
}
}
}()
return 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)
}
// linkDeserialize deserializes a raw message received from netlink into
// a link object.
func linkDeserialize(m []byte) (Link, error) {
msg := nl.DeserializeIfInfomsg(m)
attrs, err := nl.ParseRouteAttr(m[msg.Len():])
if err != nil {
return nil, err
}
base := LinkAttrs{Index: int(msg.Index), Flags: linkFlags(msg.Flags)}
var link Link
linkType := ""
for _, attr := range attrs {
switch attr.Attr.Type {
case syscall.IFLA_LINKINFO:
infos, err := nl.ParseRouteAttr(attr.Value)
if err != nil {
return nil, err
}
for _, info := range infos {
switch info.Attr.Type {
case nl.IFLA_INFO_KIND:
linkType = string(info.Value[:len(info.Value)-1])
switch linkType {
case "dummy":
link = &Dummy{}
case "ifb":
link = &Ifb{}
case "bridge":
link = &Bridge{}
case "vlan":
link = &Vlan{}
case "veth":
link = &Veth{}
case "vxlan":
link = &Vxlan{}
case "ipvlan":
link = &IPVlan{}
case "macvlan":
link = &Macvlan{}
case "macvtap":
link = &Macvtap{}
default:
link = &GenericLink{LinkType: linkType}
}
case nl.IFLA_INFO_DATA:
data, err := nl.ParseRouteAttr(info.Value)
if err != nil {
return nil, err
}
switch linkType {
case "vlan":
parseVlanData(link, data)
case "vxlan":
parseVxlanData(link, data)
case "ipvlan":
parseIPVlanData(link, data)
case "macvlan":
parseMacvlanData(link, data)
case "macvtap":
parseMacvtapData(link, data)
}
}
}
case syscall.IFLA_ADDRESS:
var nonzero bool
for _, b := range attr.Value {
if b != 0 {
nonzero = true
}
}
if nonzero {
base.HardwareAddr = attr.Value[:]
}
case syscall.IFLA_IFNAME:
base.Name = string(attr.Value[:len(attr.Value)-1])
case syscall.IFLA_MTU:
base.MTU = int(native.Uint32(attr.Value[0:4]))
case syscall.IFLA_LINK:
base.ParentIndex = int(native.Uint32(attr.Value[0:4]))
case syscall.IFLA_MASTER:
base.MasterIndex = int(native.Uint32(attr.Value[0:4]))
case syscall.IFLA_TXQLEN:
base.TxQLen = int(native.Uint32(attr.Value[0:4]))
}
}
// Links that don't have IFLA_INFO_KIND are hardware devices
if link == nil {
link = &Device{}
}
*link.Attrs() = base
return link, nil
}