Beispiel #1
0
func decodeLLDP(b []byte) (nom.Node, nom.Port, error) {
	h := lldp.NewLinkDiscoveryProtocolWithBuf(b)
	size := h.Size()

	tlvb := b[size:]
	chTLV := lldp.NewChassisMacTLVWithBuf(tlvb)
	if chTLV.Size() == 0 {
		return nom.Node{}, nom.Port{}, errors.New("decodeLLDP: no chassis id")
	}
	n := nom.Node{
		MACAddr: chTLV.MacAddr(),
	}
	size += chTLV.Size()

	tlvb = b[size:]
	pTLV := lldp.NewLinkDiscoveryTLVWithBuf(tlvb)
	if pTLV.Size() == 0 || pTLV.Type() != uint8(lldp.TLV_PORT_ID) {
		return nom.Node{}, nom.Port{}, errors.New("decodeLLDP: no port id")
	}

	v := pTLV.Value()
	if v[0] != uint8(lldp.PORT_TLV_IFACE_NAME) {
		return nom.Node{}, nom.Port{}, errors.New("decodeLLDP: no port iface name")
	}

	portUID := nom.UID(v[1:])
	nID, pID := nom.ParsePortUID(portUID)
	n.ID = nID

	return n, nom.Port{ID: pID, Node: n.UID()}, nil
}
Beispiel #2
0
func encodeLLDP(n nom.Node, p nom.Port) []byte {
	b := make([]byte, 256)
	h := lldp.NewLinkDiscoveryProtocolWithBuf(b)
	h.Init()
	h.SetSrcMac(n.MACAddr)
	h.SetDstMac([6]byte{0x01, 0x80, 0xC2, 0x00, 0x00, 0x0E})
	size := h.Size()

	tlvb := b[size:]
	chTLV := lldp.NewChassisMacTLVWithBuf(tlvb)
	chTLV.Init()
	chTLV.SetMacAddr(n.MACAddr)
	size += chTLV.Size()

	tlvb = b[size:]
	pTLV := lldp.NewLinkDiscoveryTLVWithBuf(tlvb)
	pTLV.Init()
	pTLV.SetType(uint8(lldp.TLV_PORT_ID))

	pTLV.AddValue(byte(lldp.PORT_TLV_IFACE_NAME))
	for _, v := range []byte(p.UID()) {
		pTLV.AddValue(v)
	}
	size += pTLV.Size()

	tlvb = b[size:]
	ttlTLV := lldp.NewLinkDiscoveryTLVWithBuf(tlvb)
	ttlTLV.Init()
	ttlTLV.SetType(uint8(lldp.TLV_TTL))
	ttlTLV.AddValue(0)
	ttlTLV.AddValue(0xFF)

	size += ttlTLV.Size()

	// TODO(soheil): Maybe add a few custom fields?
	return b[:size]
}