def do_flow_mod(self, event=None):
"""
If the event is not specified, then issues a flow mod with random src
and dst ports; all the other fields will match against the trigger event
saved earlier. Does not issue pkt_out.
Otherwise, does a normal flow_mod.
"""
msg = of.ofp_flow_mod()
# Normal flow-mod
if event:
msg.match = of.ofp_match.from_packet(event.parse())
msg.actions.append(of.ofp_action_output(port=get_the_other_port(event.port)))
msg.buffer_id = event.ofp.buffer_id
# Save the trigger event for later matching.
if msg.match.tp_dst == TRIGGER_PORT:
with self.lock:
self.trigger_event = event
mylog('Received trigger event. Trigger event.parse() =', pretty_dict(dictify(event.parse())))
mylog('Installed flow:', pretty_dict(dictify(msg.match)))
# Special flow-mod that generates random source/dst ports.
else:
with self.lock:
assert self.trigger_event
trigger_packet = func_cache(self.trigger_event.parse)
msg.match = of.ofp_match.from_packet(trigger_packet)
msg.actions.append(of.ofp_action_output(port=get_the_other_port(self.trigger_event.port)))
msg.match.tp_dst = random.randint(10, 65000)
msg.match.tp_src = random.randint(10, 65000)
current_time = time.time()
with self.lock:
(count, start, _) = self.flow_mod_stat
if start is None: start = current_time
self.flow_mod_stat = (count + 1, start, current_time)
msg.idle_timeout = IDLE_TIMEOUT
msg.hard_timeout = HARD_TIMEOUT
if (not USE_LIMITER) or (USE_LIMITER and self.flow_mod_limiter.to_forward_packet()):
self._of_send(msg)
self.flow_mod_queue.put((current_time, event.parse()))
def do_pkt_out(self, event=None):
msg = of.ofp_packet_out()
# Normal pkt-out
if event:
if event.ofp.buffer_id == -1:
mylog("Not flooding unbuffered packet on", dpidToStr(event.dpid))
return
msg.actions.append(of.ofp_action_output(port=get_the_other_port(event.port)))
msg.buffer_id = event.ofp.buffer_id
msg.in_port = event.port
mylog('Normal packet-out: ', msg)
# Special pkt-out that generates a packet that is exactly the same as
# the trigger packet. Unfortunately, only 114 bytes of the original
# ingress packet are forwarded into the controller as pkt-in. We need to
# make up for the truncated length, if needed. The checksum will be
# wrong, but screw that.
else:
raw_data = func_cache(self.trigger_event.parse).raw
if len(raw_data) < self.pkt_out_length:
raw_data += 'z' * (self.pkt_out_length - len(raw_data))
msg._data = raw_data
msg.buffer_id = -1
with self.lock:
assert self.trigger_event
msg.actions.append(of.ofp_action_output(port=get_the_other_port(self.trigger_event.port)))
msg.in_port = self.trigger_event.port
# Stat collection for special pkt-out only.
current_time = time.time()
with self.lock:
(count, start, _) = self.pkt_out_stat
if start is None: start = current_time
self.pkt_out_stat = (count + 1, start, current_time)
if (not USE_LIMITER) or (USE_LIMITER and self.dyn_limiter.to_forward_packet(DynamicLimiter.PacketType.PktOut)):
self._of_send(msg)
