func (b *Bridge) snooper() {
var (
dot1q layers.Dot1Q
eth layers.Ethernet
ip4 layers.IPv4
ip6 layers.IPv6
arp layers.ARP
)
parser := gopacket.NewDecodingLayerParser(layers.LayerTypeEthernet,
&dot1q,
ð,
&ip4,
&ip6,
&arp,
)
decodedLayers := []gopacket.LayerType{}
for {
data, _, err := b.handle.ReadPacketData()
if err != nil {
if err != io.EOF {
log.Error("error reading packet data: ", err)
}
break
}
if err := parser.DecodeLayers(data, &decodedLayers); err != nil {
if err2, ok := err.(gopacket.UnsupportedLayerType); ok {
switch gopacket.LayerType(err2) {
case layers.LayerTypeICMPv6, gopacket.LayerTypePayload:
// ignore
err = nil
default:
continue
}
}
if err != nil {
log.Error("error parsing packet: %v", err)
continue
}
}
for _, layerType := range decodedLayers {
switch layerType {
case layers.LayerTypeICMPv6:
b.updateIP(eth.SrcMAC.String(), ip6.SrcIP)
case layers.LayerTypeARP:
b.updateIP(eth.SrcMAC.String(), net.IP(arp.SourceProtAddress))
}
}
}
log.Info("%v snoop out", b.Name)
}
func (f *tomLayerFactory) Create(layerType gopacket.LayerType) gopacket.DecodingLayer {
d := int(layerType - gopacket.LayerType(TOM_LAYERS_BASE_NUM))
if d < 0 || d > 255 {
panic("FIXME")
//return gopacket.LayerTypeZero // FIXME
}
m := TomMessageTypeMetadata[d]
errs.Check(m.LayerType == layerType)
return m.CreateLayer()
}