master-thesis/p4app/controller.py

from __future__ import unicode_literals

import nnpy
import struct

from p4utils.utils.topology import Topology
from p4utils.utils.sswitch_API import SimpleSwitchAPI

from scapy.all import sniff, get_if_list, Ether, get_if_hwaddr, sendp
from scapy.all import IP, Raw, IPv6, TCP, TCP_client
from scapy.all import Ether, sniff, Packet, BitField

import sys
import re

import logging
import argparse
import subprocess

# Broken in python2
import ipaddress

logging.basicConfig()
log = logging.getLogger("main")



class CpuHeader(Packet):
    name = 'CpuPacket'
    fields_desc = [BitField('ingress_port', 0, 16)]


class L2Controller(object):
    def __init__(self, sw_name):
        # Command line mapping
        self.modes = ['base', 'router']

        self.info={}
        self.info['ndp_multicast'] = ipaddress.ip_network(u"ff02::1:ff00:0/104")

        self.address_suffix = 42

        # Network / egress
        self.v6_mask = "64"

        self.v6_routes = {}
        self.v6_routes[None] = []
        self.v6_routes['base'] = []
        self.v6_routes['base'].append({ "net": "2001:db8:61::", "port": "1"})
        self.v6_routes['base'].append({ "net": "2001:db8:62::", "port": "2"})
        self.v6_routes['router'] = self.v6_routes['base']

        self.v4_mask = "24"
        self.v4_routes = {}
        self.v4_routes[None] = []
        self.v4_routes['base'] = []
        self.v4_routes['base'].append({ "net": "10.0.41.", "port": "3"})
        self.v4_routes['base'].append({ "net": "10.0.42.", "port": "4"})
        self.v4_routes['router'] = self.v4_routes['base']

        self.v6_addresses = {}
        self.v6_addresses[None] = []
        self.v6_addresses['base'] = []
        self.v6_addresses['router'] = [ { "addr": "{}{}".format(n['net'], self.address_suffix), "port": n['port'] } for n in self.v6_routes['router'] ]

        self.v4_addresses = {}
        self.v4_addresses[None] = []
        self.v4_addresses['base'] = []
        self.v4_addresses['router'] = [ { "addr": "{}{}".format(n['net'], self.address_suffix), "port": n['port'] } for n in self.v4_routes['router'] ]

        self.init_boilerplate(sw_name)

    @staticmethod
    def prefix_to_net(net, mask):
        """ work around ipaddress bug """
        net = "{}0/{}".format(net, mask)
        log.debug("net: {}".format(net))
        return net

    @staticmethod
    def prefix_to_host(net, mask):
        """ work around ipaddress bug """
        host = "{}1/{}".format(net, mask)
        log.debug("host: {}".format(host))
        return "{}1/{}".format(net, mask)

    @staticmethod
    def add_host_ips(host, net, ipaddr, dev):
        subprocess.call(["mx", host, "ip", "addr", "flush", "dev", dev])
        for v6dev in [ "lo", "default", "all", dev ]:
            subprocess.call(["mx", host, "sysctl", "net.ipv6.conf.{}.disable_ipv6=0".format(v6dev)])

        # Set down & up to regain link local address
        subprocess.call(["mx", host, "ip", "link", "set", dev, "down"])
        subprocess.call(["mx", host, "ip", "link", "set", dev, "up"])

        # Now add global address
        subprocess.call(["mx", host, "ip", "addr", "add", ipaddr, "dev", dev])

    def init_ndp(self):
        """ initialise neighbor discovery protocol"""

        # https://en.wikipedia.org/wiki/Solicited-node_multicast_address
        ndp_prefix = "ff02::1:ff00:0/104"

        all_ports = range(1,5)
        # create multicast nodes
        for rid in range(1,5):
            ports = [ x for x in all_ports if not x == rid ]
            n_handle = self.controller.mc_node_create(rid, ports)
            log.debug("Creating MC node rid={} ports={} handle={}".format(rid, ports, n_handle))

            g_handle = self.controller.mc_mgrp_create(rid)
            log.debug("Creating MC group mgrp={} handle={} && associating afterwards".format(rid, g_handle))

            self.controller.mc_node_associate(g_handle, n_handle)


        self.controller.table_clear("ndp")
        for port in all_ports:
            self.controller.table_add("ndp", "multicast_pkg", [ndp_prefix, str(port)], [str(port)])


        # Special rule for switch entries
        self.controller.table_add("ndp_answer", "icmp6_neighbor_solicitation", ["ff02::1:ff00:42", "135"], ["2001:db8:61::42"])

    def init_boilerplate(self, sw_name):
        self.topo = Topology(db="topology.db")
        self.sw_name = sw_name
        self.thrift_port = self.topo.get_thrift_port(sw_name)
        self.cpu_port =  self.topo.get_cpu_port_index(self.sw_name)
        self.controller = SimpleSwitchAPI(self.thrift_port)
        self.intf = str(self.topo.get_cpu_port_intf(self.sw_name).replace("eth0", "eth1"))
        self.controller.reset_state()

        if self.cpu_port:
            self.controller.mirroring_add(100, self.cpu_port)

#        self.init_ndp()

    def config(self):
        self.fill_tables()
        self.config_hosts()


    def fill_tables(self):
        self.controller.table_clear("v6_networks")
        for v6route in self.v6_routes[self.mode]:
            net = self.prefix_to_net(v6route['net'], self.v6_mask)
            self.controller.table_add("v6_networks", "set_egress_port", [net], [v6route['port']])

        net = str(self.info['ndp_multicast'])
        self.controller.table_add("v6_networks", "controller_reply", [net])


        self.controller.table_clear("v4_routing")
        for v4route in self.v4_routes[self.mode]:
            net = self.prefix_to_net(v4route['net'], self.v4_mask)
            self.controller.table_add("v4_routing", "set_egress_port", [net], [v4route['port']])

        self.controller.table_clear("v6_addresses")
        for v6addr in self.v6_addresses[self.mode]:
            self.controller.table_add("v6_addresses", "controller_reply", [v6addr['addr']])


    def gen_ndp_multicast_addr(self, addr):
        """ append the 24 bit of the address to the multicast address"""
        return ipaddress.ip_address(int(self.info['ndp_multicast']) + (int(addr) & 0xffffff))

    def config_hosts(self):
        """ Assumptions:
        - all routes are networks (no /128 v6 or /32 v4
        - hosts get the first ip address in the network
        """

        for v6route in self.v6_routes[self.mode]:
            host   = "h{}".format(v6route['port'])
            dev    = "{}-eth0".format(host)
            #net    = ipaddress.ip_network(v6route['net'])
            #ipaddr = "{}/{}".format(net[1],net.prefix_length)
            net    = self.prefix_to_net(v6route['net'], self.v6_mask)
            ipaddr = self.prefix_to_host(v6route['net'], self.v6_mask)

            self.add_host_ips(host, net, ipaddr, dev)

            # mx h$i "ip -6 route add default via 2001:db8:6::42"

        #for v4route in self.v4_routes[self.mode]:
        # Todo: add v4 routes / ip addresses

        # Fake mac addresses - this gets REALLY messy now
        # for host in range(4):
        #     macrange = [1, 2, 3, 4, 42]

        #     for mac in macrange:
        #         subprocess.call(["mx", host, "ip", "addr", "add", ipaddr, "dev", dev])


    def debug_print_pkg(self, pkg, msg="INCOMING"):
        #log.debug("{}: {}".format(msg, self.debug_format_pkg(pkg)))
        log.debug("{}: {}".format(msg, pkg.__repr__()))

    def debug_format_pkg(self, pkg):
        packet = Ether(str(pkg))

        if packet.type == 0x800:
            ip = pkg.getlayer(IP)
        elif packet.type == 0x86dd:
            ip = pkg.getlayer(IPv6)

        # tcp = pkg.getlayer(TCP)

        # raw = pkg.getlayer(Raw)

        # return "{}:{} => {}:{}: flags={} seq={} ack={} raw={}".format(
        #     ip.src, tcp.sport,
        #     ip.dst, tcp.dport,
        #     tcp.flags,
        #     tcp.seq,
        #     tcp.ack,
        #     raw)


    def recv_msg_cpu(self, pkg):
        packet = Ether(str(pkg))

        self.debug_print_pkg(pkg)

        if packet.type == 0x0800:
            pass
        elif packet.type == 0x86dd:
            pass
        elif packet.type == 0x4242:
            print("Special handling needed")
            pass
        elif packet.type == 0x2323:
            print("Debug pkg")
            pass
        else:
            print("Broken pkg: {}".format(pkg.__repr__()))
            return

    def run_cpu_port_loop(self):
        sniff(iface=self.intf, prn=self.recv_msg_cpu)

    def commandline(self):
        parser = argparse.ArgumentParser(description='controller++')
        parser.add_argument('--mode', help='Select mode / settings to use', choices=self.modes)
        parser.add_argument('--debug', help='Enable debug logging', action='store_true')

        self.args = parser.parse_args()
        self.mode = self.args.mode


if __name__ == "__main__":
    import sys
    import os

    if "DEBUG" in os.environ:
        log.setLevel(logging.DEBUG)
    else:
        log.setLevel(logging.INFO)

    log.info("Booting...")
    log.debug("Debug enabled.")

    sw_name = "s1"
    controller = L2Controller(sw_name)

    controller.commandline()
    if controller.args.debug:
        log.setLevel(logging.DEBUG)
    controller.config()
    controller.run_cpu_port_loop()