pyretic_switch.py

# CS 6250 Summer 2020 - Project 4 - SDN Firewall
# build atlas-v13
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# The Pyretic Project                                                          #
# frenetic-lang.org/pyretic                                                    #
# author: Joshua Reich (jreich@cs.princeton.edu)                               #
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from pyretic.lib.corelib import *
from pyretic.lib.std import *
from pyretic.lib.query import *

class ActLikeSwitch(DynamicPolicy):
    def __init__(self):
        super(ActLikeSwitch, self).__init__()
        # Set up the initial forwarding behavior for your mac learning switch to flood 
        # all packets
        self.forward = flood()

        # Set up a query that will receive new incoming packets
        self.query = packets(limit=1,group_by=['srcmac','switch'])
        # Set the initial internal policy value (each dynamic policy has a member 'policy'
        # when this member is assigned, the dynamic policy updates itself)
        self.policy = self.forward + self.query

        self.query.register_callback(self.learn_from_a_packet)

    def learn_from_a_packet(self, pkt):
        # Set the forwarding policy
        self.forward = if_(match(dstmac=pkt['srcmac'],
                                 switch=pkt['switch']), fwd(pkt['inport']),
                           self.forward)  # hint use 'match', '&', 'if_', and 'fwd' 
        # Update the policy
        self.policy = self.forward + self.query # hint you've already written this
        print self.policy 

    
def main():
    return ActLikeSwitch()