def create_discovery_packet(self, dpid, port_num, port_addr):
"""
Build discovery packet
"""
chassis_id = pkt.chassis_id(subtype=pkt.chassis_id.SUB_LOCAL)
chassis_id.id = bytes('dpid:' + hex(long(dpid))[2:-1])
# Maybe this should be a MAC. But a MAC of what? Local port, maybe?
port_id = pkt.port_id(subtype=pkt.port_id.SUB_PORT, id=str(port_num))
ttl = pkt.ttl(ttl=self._ttl)
sysdesc = pkt.system_description()
sysdesc.payload = bytes('dpid:' + hex(long(dpid))[2:-1])
discovery_packet = pkt.lldp()
discovery_packet.tlvs.append(chassis_id)
discovery_packet.tlvs.append(port_id)
discovery_packet.tlvs.append(ttl)
discovery_packet.tlvs.append(sysdesc)
discovery_packet.tlvs.append(pkt.end_tlv())
eth = pkt.ethernet(type=pkt.ethernet.LLDP_TYPE)
eth.src = port_addr
eth.dst = pkt.ETHERNET.NDP_MULTICAST
eth.payload = discovery_packet
po = of.ofp_packet_out(action=of.ofp_action_output(port=port_num))
po.data = eth.pack()
return po.pack()
def create_discovery_packet (self, dpid, port_num, port_addr):
"""
Build discovery packet
"""
chassis_id = pkt.chassis_id(subtype=pkt.chassis_id.SUB_LOCAL)
chassis_id.id = bytes('dpid:' + hex(long(dpid))[2:-1])
# Maybe this should be a MAC. But a MAC of what? Local port, maybe?
port_id = pkt.port_id(subtype=pkt.port_id.SUB_PORT, id=str(port_num))
ttl = pkt.ttl(ttl = self._ttl)
sysdesc = pkt.system_description()
sysdesc.payload = bytes('dpid:' + hex(long(dpid))[2:-1])
discovery_packet = pkt.lldp()
discovery_packet.tlvs.append(chassis_id)
discovery_packet.tlvs.append(port_id)
discovery_packet.tlvs.append(ttl)
discovery_packet.tlvs.append(sysdesc)
discovery_packet.tlvs.append(pkt.end_tlv())
eth = pkt.ethernet(type=pkt.ethernet.LLDP_TYPE)
eth.src = port_addr
eth.dst = pkt.ETHERNET.NDP_MULTICAST
eth.payload = discovery_packet
po = of.ofp_packet_out(action = of.ofp_action_output(port=port_num))
po.data = eth.pack()
return po.pack()
def _handle_openflow_PacketIn(self, event):
"""
Receive and process LLDP packets
"""
packet = event.parsed
if (packet.effective_ethertype != pkt.ethernet.LLDP_TYPE
or packet.dst != pkt.ETHERNET.NDP_MULTICAST):
if not self._eat_early_packets: return
if not event.connection.connect_time: return
enable_time = time.time() - self.send_cycle_time - 1
if event.connection.connect_time > enable_time:
return EventHalt
return
if self._explicit_drop:
if event.ofp.buffer_id is not None:
log.debug("Dropping LLDP packet %i", event.ofp.buffer_id)
msg = of.ofp_packet_out()
msg.buffer_id = event.ofp.buffer_id
msg.in_port = event.port
event.connection.send(msg)
lldph = packet.find(pkt.lldp)
if lldph is None or not lldph.parsed:
log.error("LLDP packet could not be parsed")
return EventHalt
if len(lldph.tlvs) < 3:
log.error("LLDP packet without required three TLVs")
return EventHalt
if lldph.tlvs[0].tlv_type != pkt.lldp.CHASSIS_ID_TLV:
log.error("LLDP packet TLV 1 not CHASSIS_ID")
return EventHalt
if lldph.tlvs[1].tlv_type != pkt.lldp.PORT_ID_TLV:
log.error("LLDP packet TLV 2 not PORT_ID")
return EventHalt
if lldph.tlvs[2].tlv_type != pkt.lldp.TTL_TLV:
log.error("LLDP packet TLV 3 not TTL")
return EventHalt
def lookInSysDesc():
r = None
for t in lldph.tlvs[3:]:
if t.tlv_type == pkt.lldp.SYSTEM_DESC_TLV:
# This is our favored way...
for line in t.payload.split('\n'):
if line.startswith('dpid:'):
try:
return int(line[5:], 16)
except:
pass
if len(t.payload) == 8:
# Maybe it's a FlowVisor LLDP...
# Do these still exist?
try:
return struct.unpack("!Q", t.payload)[0]
except:
pass
return None
originatorDPID = lookInSysDesc()
if originatorDPID == None:
# We'll look in the CHASSIS ID
if lldph.tlvs[0].subtype == pkt.chassis_id.SUB_LOCAL:
if lldph.tlvs[0].id.startswith('dpid:'):
# This is how NOX does it at the time of writing
try:
originatorDPID = int(lldph.tlvs[0].id[5:], 16)
except:
pass
if originatorDPID == None:
if lldph.tlvs[0].subtype == pkt.chassis_id.SUB_MAC:
# Last ditch effort -- we'll hope the DPID was small enough
# to fit into an ethernet address
if len(lldph.tlvs[0].id) == 6:
try:
s = lldph.tlvs[0].id
originatorDPID = struct.unpack(
"!Q", '\x00\x00' + s)[0]
except:
pass
if originatorDPID == None:
log.warning("Couldn't find a DPID in the LLDP packet")
return EventHalt
if originatorDPID not in core.openflow.connections:
log.info('Received LLDP packet from unknown switch')
return EventHalt
# Get port number from port TLV
if lldph.tlvs[1].subtype != pkt.port_id.SUB_PORT:
log.warning(
"Thought we found a DPID, but packet didn't have a port")
return EventHalt
originatorPort = None
if lldph.tlvs[1].id.isdigit():
# We expect it to be a decimal value
originatorPort = int(lldph.tlvs[1].id)
elif len(lldph.tlvs[1].id) == 2:
# Maybe it's a 16 bit port number...
try:
originatorPort = struct.unpack("!H", lldph.tlvs[1].id)[0]
except:
pass
if originatorPort is None:
log.warning("Thought we found a DPID, but port number didn't " +
"make sense")
return EventHalt
if (event.dpid, event.port) == (originatorDPID, originatorPort):
log.warning("Port received its own LLDP packet; ignoring")
return EventHalt
link = Discovery.Link(originatorDPID, originatorPort, event.dpid,
event.port)
if link not in self.adjacency:
self.adjacency[link] = time.time()
log.info('link detected: %s', link)
self.raiseEventNoErrors(LinkEvent, True, link)
else:
# Just update timestamp
self.adjacency[link] = time.time()
return EventHalt # Probably nobody else needs this event
def _handle_openflow_PacketIn (self, event):
"""
Receive and process LLDP packets
"""
packet = event.parsed
if (packet.effective_ethertype != pkt.ethernet.LLDP_TYPE
or packet.dst != pkt.ETHERNET.NDP_MULTICAST):
if not self._eat_early_packets: return
if not event.connection.connect_time: return
enable_time = time.time() - self.send_cycle_time - 1
if event.connection.connect_time > enable_time:
return EventHalt
return
if self._explicit_drop:
if event.ofp.buffer_id is not None:
log.debug("Dropping LLDP packet %i", event.ofp.buffer_id)
msg = of.ofp_packet_out()
msg.buffer_id = event.ofp.buffer_id
msg.in_port = event.port
event.connection.send(msg)
lldph = packet.find(pkt.lldp)
if lldph is None or not lldph.parsed:
log.error("LLDP packet could not be parsed")
return EventHalt
if len(lldph.tlvs) < 3:
log.error("LLDP packet without required three TLVs")
return EventHalt
if lldph.tlvs[0].tlv_type != pkt.lldp.CHASSIS_ID_TLV:
log.error("LLDP packet TLV 1 not CHASSIS_ID")
return EventHalt
if lldph.tlvs[1].tlv_type != pkt.lldp.PORT_ID_TLV:
log.error("LLDP packet TLV 2 not PORT_ID")
return EventHalt
if lldph.tlvs[2].tlv_type != pkt.lldp.TTL_TLV:
log.error("LLDP packet TLV 3 not TTL")
return EventHalt
def lookInSysDesc ():
r = None
for t in lldph.tlvs[3:]:
if t.tlv_type == pkt.lldp.SYSTEM_DESC_TLV:
# This is our favored way...
for line in t.payload.split('\n'):
if line.startswith('dpid:'):
try:
return int(line[5:], 16)
except:
pass
if len(t.payload) == 8:
# Maybe it's a FlowVisor LLDP...
# Do these still exist?
try:
return struct.unpack("!Q", t.payload)[0]
except:
pass
return None
originatorDPID = lookInSysDesc()
if originatorDPID == None:
# We'll look in the CHASSIS ID
if lldph.tlvs[0].subtype == pkt.chassis_id.SUB_LOCAL:
if lldph.tlvs[0].id.startswith('dpid:'):
# This is how NOX does it at the time of writing
try:
originatorDPID = int(lldph.tlvs[0].id[5:], 16)
except:
pass
if originatorDPID == None:
if lldph.tlvs[0].subtype == pkt.chassis_id.SUB_MAC:
# Last ditch effort -- we'll hope the DPID was small enough
# to fit into an ethernet address
if len(lldph.tlvs[0].id) == 6:
try:
s = lldph.tlvs[0].id
originatorDPID = struct.unpack("!Q",'\x00\x00' + s)[0]
except:
pass
if originatorDPID == None:
log.warning("Couldn't find a DPID in the LLDP packet")
return EventHalt
if originatorDPID not in core.openflow.connections:
log.info('Received LLDP packet from unknown switch')
return EventHalt
# Get port number from port TLV
if lldph.tlvs[1].subtype != pkt.port_id.SUB_PORT:
log.warning("Thought we found a DPID, but packet didn't have a port")
return EventHalt
originatorPort = None
if lldph.tlvs[1].id.isdigit():
# We expect it to be a decimal value
originatorPort = int(lldph.tlvs[1].id)
elif len(lldph.tlvs[1].id) == 2:
# Maybe it's a 16 bit port number...
try:
originatorPort = struct.unpack("!H", lldph.tlvs[1].id)[0]
except:
pass
if originatorPort is None:
log.warning("Thought we found a DPID, but port number didn't " +
"make sense")
return EventHalt
if (event.dpid, event.port) == (originatorDPID, originatorPort):
log.warning("Port received its own LLDP packet; ignoring")
return EventHalt
link = Discovery.Link(originatorDPID, originatorPort, event.dpid,
event.port)
if link not in self.adjacency:
self.adjacency[link] = time.time()
log.info('link detected: %s', link)
self.raiseEventNoErrors(LinkEvent, True, link)
else:
# Just update timestamp
self.adjacency[link] = time.time()
return EventHalt # Probably nobody else needs this event
