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Diffstat (limited to 'vicn/resource/ns3/emulated_channel.py')
| -rw-r--r-- | vicn/resource/ns3/emulated_channel.py | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/vicn/resource/ns3/emulated_channel.py b/vicn/resource/ns3/emulated_channel.py new file mode 100644 index 00000000..08d7a14b --- /dev/null +++ b/vicn/resource/ns3/emulated_channel.py @@ -0,0 +1,209 @@ +#!/usr/bin/env python3 +# -*- coding: utf-8 -*- +# +# Copyright (c) 2017 Cisco and/or its affiliates. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at: +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +import logging +import random + +from netmodel.model.type import Integer +from netmodel.util.socket import check_port +from vicn.core.address_mgr import AddressManager +from vicn.core.attribute import Attribute, Multiplicity +from vicn.core.exception import ResourceNotFound +from vicn.core.requirement import Requirement +from vicn.core.resource import BaseResource +from vicn.core.resource_mgr import wait_resources +from vicn.core.task import inline_task, async_task, task +from vicn.core.task import BashTask, run_task +from vicn.resource.channel import Channel +from vicn.resource.linux.application import LinuxApplication as Application +from vicn.resource.linux.net_device import NetDevice +from vicn.resource.linux.tap_device import TapDevice +from vicn.resource.linux.veth_pair import VethPair +from vicn.resource.lxd.lxc_container import LxcContainer +from vicn.resource.node import Node + +log = logging.getLogger(__name__) + +class EmulatedChannel(Channel, Application): + """EmulatedChannel resource + + This resources serves as a base class for wireless channels emulated by + means of ns3 simulation. + + Attributes: + ap (Reference[node]): Reference to the AP node + stations (Reference[node]): Reference to the list of stations. + control_port (int): Port used to communicate with the management + interface of the simulation. + + Implementation notes: + - Both AP and stations are allocated a separate VLAN to isolate broadcast + traffic and prevent loops on the bridge. + - We also need that all interfaces related to ap and stations are created + before we run the commandline (currently, dynamically adding/removing + AP and stations is not supported by the emulator). This is made + possible thanks to the key=True parameter, which makes sure the + attributes are processed before the __create__ is called. + + Todo: + - Retrieve the process PID to kill it during __delete__ + """ + + __resource_type__ = BaseResource + + ap = Attribute(Node, description = 'AP', key = True) + stations = Attribute(Node, description = 'List of stations', + multiplicity = Multiplicity.OneToMany, key = True) + control_port = Attribute(Integer, + description = 'Control port for the simulation') + + # Overloaded attributes + node = Attribute(requirements = [ + Requirement('bridge') + ]) + + #-------------------------------------------------------------------------- + # Constructor + #-------------------------------------------------------------------------- + + def __init__(self, *args, **kwargs): + super().__init__(*args, **kwargs) + + # AP (resp. stations) interfaces (for external connectivity) and + # tap_devices (for connection to emulator) + self._ap_if = None + self._ap_tap = None + self._sta_ifs = dict() + self._sta_taps = dict() + + # Device names to be attached to the bridge (differs according to the + # node type, Physical or LxcContainer, and eventually None for an + # unmanaged stations) + self._ap_bridged = None + self._sta_bridged = dict() + + #-------------------------------------------------------------------------- + # Resource lifecycle + #-------------------------------------------------------------------------- + + @inline_task + def __get__(self): + raise ResourceNotFound + + def __create__(self): + # NOTE: http://stackoverflow.com/questions/21141352/python-subprocess- + # calling-a-script-which-runs-a-background-process-hanging + # The output of the background scripts is still going to the same file + # descriptor as the child script, thus the parent script waits for it + # to finish. + cmd = '(' + self.__app_name__ + ' ' + self._get_cmdline_params() + \ + '>/dev/null 2>&1) &' + return BashTask(self.node, cmd) + + def __delete__(self): + raise NotImplementedError + + #-------------------------------------------------------------------------- + # Attribute handlers + #-------------------------------------------------------------------------- + + @async_task + async def _set_ap(self, ap=None): + if ap is None: + ap = self.ap + if ap is None: + log.info('Ignored setting ap to None...') + return + + # Add a WiFi interface for the AP... + interfaces = list() + if isinstance(ap, LxcContainer): + # Ideally, We need to create a VethPair for each station + # This should be monitored for the total channel bw + host = NetDevice(node = ap.node, + device_name='vhh-' + ap.name + '-' + self.name, + monitored = False, + managed = False) + self._ap_if = VethPair(node = self.ap, + name = 'vh-' + ap.name + '-' + self.name, + device_name = 'vh-' + ap.name + '-' + self.name, + host = host, + owner = self) + self._ap_bridged = self._ap_if.host + else: + raise NotImplementedError + self._state.manager.commit_resource(self._ap_if) + + interfaces.append(self._ap_if) + + # Add a tap interface for the AP... + self._ap_tap = TapDevice(node = self.node, + owner = self, + device_name = 'tap-' + ap.name + '-' + self.name, + up = True, + promiscuous = True, + monitored = False) + self._state.manager.commit_resource(self._ap_tap) + interfaces.append(self._ap_tap) + + # Wait for interfaces to be setup + await wait_resources(interfaces) + + # NOTE: only set channel after the resource is created or it might + # create loops which, at this time, are not handled + self._ap_if.set('channel', self) + + # Add interfaces to bridge + vlan = AddressManager().get('vlan', self, tag='ap') + + # AS the container has created the VethPair already without Vlan, we + # need to delete and recreate it + task = self.node.bridge._remove_interface(self._ap_bridged) + await run_task(task, self._state.manager) + task = self.node.bridge._add_interface(self._ap_bridged, vlan = vlan) + await run_task(task, self._state.manager) + + task = self.node.bridge._add_interface(self._ap_tap, vlan = vlan) + await run_task(task, self._state.manager) + + print('/!\ pass information to the running simulation') + + @inline_task + def _get_ap(self): + return {'ap': None} + + @inline_task + def _get_stations(self): + return {'stations': list()} + + @async_task + async def _set_stations(self, stations=None): + print('adding stations...') + if stations is None: + stations = self.stations + + for station in stations: + await self._add_station(station) + + def _add_stations(self, stations): + raise NotImplementedError + + @inline_task + def _remove_stations(self, station): + raise NotImplementedError + |