core/vswitch_controller_p2p.py

   1 # Copyright 2015 Intel Corporation.
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #   http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 """VSwitch controller for Physical to Physical deployment
  16 """
  17
  18 import logging
  19
  20 from core.vswitch_controller import IVswitchController
  21 from vswitches.utils import add_ports_to_flow
  22
  23 _FLOW_TEMPLATE = {
  24     'idle_timeout': '0'
  25 }
  26 BRIDGE_NAME = 'br0'
  27
  28 class VswitchControllerP2P(IVswitchController):
  29     """VSwitch controller for P2P deployment scenario.
  30
  31     Attributes:
  32         _vswitch_class: The vSwitch class to be used.
  33         _vswitch: The vSwitch object controlled by this controller
  34         _deployment_scenario: A string describing the scenario to set-up in the
  35             constructor.
  36     """
  37     def __init__(self, vswitch_class):
  38         """Initializes up the prerequisites for the P2P deployment scenario.
  39
  40         :vswitch_class: the vSwitch class to be used.
  41         """
  42         self._logger = logging.getLogger(__name__)
  43         self._vswitch_class = vswitch_class
  44         self._vswitch = vswitch_class()
  45         self._deployment_scenario = "P2P"
  46         self._logger.debug('Creation using ' + str(self._vswitch_class))
  47
  48     def setup(self):
  49         """Sets up the switch for p2p.
  50         """
  51         self._logger.debug('Setup using ' + str(self._vswitch_class))
  52
  53         try:
  54             self._vswitch.start()
  55
  56             self._vswitch.add_switch(BRIDGE_NAME)
  57
  58             (_, phy1_number) = self._vswitch.add_phy_port(BRIDGE_NAME)
  59             (_, phy2_number) = self._vswitch.add_phy_port(BRIDGE_NAME)
  60
  61             self._vswitch.del_flow(BRIDGE_NAME)
  62
  63             # table#0 - flows designed to force 5 & 13 tuple matches go here
  64             flow = {'table':'0', 'priority':'1', 'actions': ['goto_table:1']}
  65             self._vswitch.add_flow(BRIDGE_NAME, flow)
  66
  67             # table#1 - flows to route packets between ports goes here. The
  68             # chosen port is communicated to subsequent tables by setting the
  69             # metadata value to the egress port number
  70             flow = {'table':'1', 'priority':'1', 'in_port':'1',
  71                     'actions': ['write_actions(output:2)', 'write_metadata:2',
  72                         'goto_table:2']}
  73             self._vswitch.add_flow(BRIDGE_NAME, flow)
  74             flow = {'table':'1', 'priority':'1', 'in_port':'2',
  75                     'actions': ['write_actions(output:1)', 'write_metadata:1',
  76                         'goto_table:2']}
  77             self._vswitch.add_flow(BRIDGE_NAME, flow)
  78
  79             # Frame modification table. Frame modification flow rules are
  80             # isolated in this table so that they can be turned on or off
  81             # without affecting the routing or tuple-matching flow rules.
  82             flow = {'table':'2', 'priority':'1', 'actions': ['goto_table:3']}
  83             self._vswitch.add_flow(BRIDGE_NAME, flow)
  84
  85             # Egress table
  86             # (TODO) Billy O'Mahony - the drop action here actually required in
  87             # order to egress the packet. This is the subject of a thread on
  88             # ovs-discuss 2015-06-30.
  89             flow = {'table':'3', 'priority':'1', 'actions': ['drop']}
  90             self._vswitch.add_flow(BRIDGE_NAME, flow)
  91
  92             flow = add_ports_to_flow(_FLOW_TEMPLATE, phy2_number, phy1_number)
  93             self._vswitch.add_flow(BRIDGE_NAME, flow)
  94
  95         except:
  96             self._vswitch.stop()
  97             raise
  98
  99     def stop(self):
 100         """Tears down the switch created in setup().
 101         """
 102         self._logger.debug('Stop using ' + str(self._vswitch_class))
 103         self._vswitch.stop()
 104
 105     def __enter__(self):
 106         self.setup()
 107
 108     def __exit__(self, type_, value, traceback):
 109         self.stop()
 110
 111     def get_vswitch(self):
 112         """See IVswitchController for description
 113         """
 114         return self._vswitch
 115
 116     def get_ports_info(self):
 117         """See IVswitchController for description
 118         """
 119         self._logger.debug('get_ports_info  using ' + str(self._vswitch_class))
 120         return self._vswitch.get_ports(BRIDGE_NAME)