vtep/ovs-vtep

   1 #!/usr/bin/python
   2 # Copyright (C) 2013 Nicira, Inc. All Rights Reserved.
   3 #
   4 # Licensed under the Apache License, Version 2.0 (the "License");
   5 # you may not use this file except in compliance with the License.
   6 # You may obtain a copy of the License at:
   7 #
   8 #     http://www.apache.org/licenses/LICENSE-2.0
   9 #
  10 # Unless required by applicable law or agreed to in writing, software
  11 # distributed under the License is distributed on an "AS IS" BASIS,
  12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 # See the License for the specific language governing permissions and
  14 # limitations under the License.
  15
  16 # Limitations:
  17 #     - Doesn't support multicast other than "unknown-dst"
  18
  19 import argparse
  20 import re
  21 import subprocess
  22 import sys
  23 import time
  24 import types
  25
  26 import ovs.dirs
  27 import ovs.util
  28 import ovs.daemon
  29 import ovs.unixctl.server
  30 import ovs.vlog
  31
  32
  33 VERSION = "0.99"
  34
  35 root_prefix = ""
  36
  37 __pychecker__ = 'no-reuseattr'  # Remove in pychecker >= 0.8.19.
  38 vlog = ovs.vlog.Vlog("ovs-vtep")
  39 exiting = False
  40
  41 Tunnel_Ip = ""
  42 Lswitches = {}
  43 Bindings = {}
  44 ls_count = 0
  45 tun_id = 0
  46
  47 def call_prog(prog, args_list):
  48     cmd = [prog, "-vconsole:off"] + args_list
  49     output = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()
  50     if len(output) == 0 or output[0] == None:
  51         output = ""
  52     else:
  53         output = output[0].strip()
  54     return output
  55
  56 def ovs_vsctl(args):
  57     return call_prog("ovs-vsctl", args.split())
  58
  59 def ovs_ofctl(args):
  60     return call_prog("ovs-ofctl", args.split())
  61
  62 def vtep_ctl(args):
  63     return call_prog("vtep-ctl", args.split())
  64
  65
  66 def unixctl_exit(conn, unused_argv, unused_aux):
  67     global exiting
  68     exiting = True
  69     conn.reply(None)
  70
  71
  72 class Logical_Switch(object):
  73     def __init__(self, ls_name):
  74         global ls_count
  75         self.name = ls_name
  76         ls_count += 1
  77         self.short_name = "vtep_ls" + str(ls_count)
  78         vlog.info("creating lswitch %s (%s)" % (self.name, self.short_name))
  79         self.ports = {}
  80         self.tunnels = {}
  81         self.local_macs = set()
  82         self.remote_macs = {}
  83         self.unknown_dsts = set()
  84         self.tunnel_key = 0
  85         self.setup_ls()
  86
  87     def __del__(self):
  88         vlog.info("destroying lswitch %s" % self.name)
  89
  90     def setup_ls(self):
  91         column = vtep_ctl("--columns=tunnel_key find logical_switch "
  92                               "name=%s" % self.name)
  93         tunnel_key = column.partition(":")[2].strip()
  94         if (tunnel_key and type(eval(tunnel_key)) == types.IntType):
  95             self.tunnel_key = tunnel_key
  96             vlog.info("using tunnel key %s in %s"
  97                       % (self.tunnel_key, self.name))
  98         else:
  99             self.tunnel_key = 0
 100             vlog.warn("invalid tunnel key for %s, using 0" % self.name)
 101
 102         ovs_vsctl("--may-exist add-br %s" % self.short_name)
 103         ovs_vsctl("br-set-external-id %s vtep_logical_switch true"
 104                   % self.short_name)
 105         ovs_vsctl("br-set-external-id %s logical_switch_name %s"
 106                   % (self.short_name, self.name))
 107
 108         vtep_ctl("clear-local-macs %s" % self.name)
 109         vtep_ctl("add-mcast-local %s unknown-dst %s" % (self.name, Tunnel_Ip))
 110
 111         ovs_ofctl("del-flows %s" % self.short_name)
 112         ovs_ofctl("add-flow %s priority=0,action=drop" % self.short_name)
 113
 114     def update_flood(self):
 115         flood_ports = self.ports.values()
 116
 117         # Traffic flowing from one 'unknown-dst' should not be flooded to
 118         # port belonging to another 'unknown-dst'.
 119         for tunnel in self.unknown_dsts:
 120             port_no = self.tunnels[tunnel][0]
 121             ovs_ofctl("add-flow %s table=1,priority=1,in_port=%s,action=%s"
 122                         % (self.short_name, port_no, ",".join(flood_ports)))
 123
 124         # Traffic coming from a VTEP physical port should only be flooded to
 125         # one 'unknown-dst' and to all other physical ports that belong to that
 126         # VTEP device and this logical switch.
 127         for tunnel in self.unknown_dsts:
 128             port_no = self.tunnels[tunnel][0]
 129             flood_ports.append(port_no)
 130             break
 131
 132         ovs_ofctl("add-flow %s table=1,priority=0,action=%s"
 133                   % (self.short_name, ",".join(flood_ports)))
 134
 135     def add_lbinding(self, lbinding):
 136         vlog.info("adding %s binding to %s" % (lbinding, self.name))
 137         port_no = ovs_vsctl("get Interface %s ofport" % lbinding)
 138         self.ports[lbinding] = port_no
 139         ovs_ofctl("add-flow %s in_port=%s,action=learn(table=1,"
 140                   "priority=1000,idle_timeout=15,cookie=0x5000,"
 141                   "NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],"
 142                   "output:NXM_OF_IN_PORT[]),resubmit(,1)"
 143                   % (self.short_name, port_no))
 144
 145         self.update_flood()
 146
 147     def del_lbinding(self, lbinding):
 148         vlog.info("removing %s binding from %s" % (lbinding, self.name))
 149         port_no = self.ports[lbinding]
 150         ovs_ofctl("del-flows %s in_port=%s" % (self.short_name, port_no));
 151         del self.ports[lbinding]
 152         self.update_flood()
 153
 154     def add_tunnel(self, tunnel):
 155         global tun_id
 156         vlog.info("adding tunnel %s" % tunnel)
 157         encap, ip = tunnel.split("/")
 158
 159         if encap != "vxlan_over_ipv4":
 160             vlog.warn("unsupported tunnel format %s" % encap)
 161             return
 162
 163         tun_id += 1
 164         tun_name = "vx" + str(tun_id)
 165
 166         ovs_vsctl("add-port %s %s -- set Interface %s type=vxlan "
 167                   "options:key=%s options:remote_ip=%s"
 168                   % (self.short_name, tun_name, tun_name, self.tunnel_key, ip))
 169
 170         for i in range(10):
 171             port_no = ovs_vsctl("get Interface %s ofport" % tun_name)
 172             if port_no != "-1":
 173                 break
 174             elif i == 9:
 175                 vlog.warn("couldn't create tunnel %s" % tunnel)
 176                 ovs_vsctl("del-port %s %s" % (self.short_name, tun_name))
 177                 return
 178
 179             # Give the system a moment to allocate the port number
 180             time.sleep(0.5)
 181
 182         self.tunnels[tunnel] = (port_no, tun_name)
 183
 184         ovs_ofctl("add-flow %s table=0,priority=1000,in_port=%s,"
 185                   "actions=resubmit(,1)"
 186                   % (self.short_name, port_no))
 187
 188     def del_tunnel(self, tunnel):
 189         vlog.info("removing tunnel %s" % tunnel)
 190
 191         port_no, tun_name = self.tunnels[tunnel]
 192         ovs_ofctl("del-flows %s table=0,in_port=%s"
 193                     % (self.short_name, port_no))
 194         ovs_vsctl("del-port %s %s" % (self.short_name, tun_name))
 195
 196         del self.tunnels[tunnel]
 197
 198     def update_local_macs(self):
 199         flows = ovs_ofctl("dump-flows %s cookie=0x5000/-1,table=1"
 200                           % self.short_name).splitlines()
 201         macs = set()
 202         for f in flows:
 203             mac = re.split(r'.*dl_dst=(.*) .*', f)
 204             if len(mac) == 3:
 205                 macs.add(mac[1])
 206
 207         for mac in macs.difference(self.local_macs):
 208             vlog.info("adding local ucast %s to %s" % (mac, self.name))
 209             vtep_ctl("add-ucast-local %s %s %s" % (self.name, mac, Tunnel_Ip))
 210
 211         for mac in self.local_macs.difference(macs):
 212             vlog.info("removing local ucast %s from %s" % (mac, self.name))
 213             vtep_ctl("del-ucast-local %s %s" % (self.name, mac))
 214
 215         self.local_macs = macs
 216
 217     def add_remote_mac(self, mac, tunnel):
 218         port_no = self.tunnels.get(tunnel, (0,""))[0]
 219         if not port_no:
 220             return
 221
 222         ovs_ofctl("add-flow %s table=1,priority=1000,dl_dst=%s,action=%s"
 223                   % (self.short_name, mac, port_no))
 224
 225     def del_remote_mac(self, mac):
 226         ovs_ofctl("del-flows %s table=1,dl_dst=%s" % (self.short_name, mac))
 227
 228     def update_remote_macs(self):
 229         remote_macs = {}
 230         unknown_dsts = set()
 231         tunnels = set()
 232         parse_ucast = True
 233
 234         mac_list = vtep_ctl("list-remote-macs %s" % self.name).splitlines()
 235         for line in mac_list:
 236             if (line.find("mcast-mac-remote") != -1):
 237                 parse_ucast = False
 238                 continue
 239
 240             entry = re.split(r'  (.*) -> (.*)', line)
 241             if len(entry) != 4:
 242                 continue
 243
 244             if parse_ucast:
 245                 remote_macs[entry[1]] = entry[2]
 246             else:
 247                 if entry[1] != "unknown-dst":
 248                     continue
 249
 250                 unknown_dsts.add(entry[2])
 251
 252             tunnels.add(entry[2])
 253
 254         old_tunnels = set(self.tunnels.keys())
 255
 256         for tunnel in tunnels.difference(old_tunnels):
 257             self.add_tunnel(tunnel)
 258
 259         for tunnel in old_tunnels.difference(tunnels):
 260             self.del_tunnel(tunnel)
 261
 262         for mac in remote_macs.keys():
 263             if (self.remote_macs.get(mac) != remote_macs[mac]):
 264                 self.add_remote_mac(mac, remote_macs[mac])
 265
 266         for mac in self.remote_macs.keys():
 267             if not remote_macs.has_key(mac):
 268                 self.del_remote_mac(mac)
 269
 270         self.remote_macs = remote_macs
 271
 272         if (self.unknown_dsts != unknown_dsts):
 273             self.unknown_dsts = unknown_dsts
 274             self.update_flood()
 275
 276     def update_stats(self):
 277         # Map Open_vSwitch's "interface:statistics" to columns of
 278         # vtep's logical_binding_stats. Since we are using the 'interface' from
 279         # the logical switch to collect stats, packets transmitted from it
 280         # is received in the physical switch and vice versa.
 281         stats_map = {'tx_packets':'packets_to_local',
 282                     'tx_bytes':'bytes_to_local',
 283                     'rx_packets':'packets_from_local',
 284                      'rx_bytes':'bytes_from_local'}
 285
 286         # Go through all the logical switch's interfaces that end with "-l"
 287         # and copy the statistics to logical_binding_stats.
 288         for interface in self.ports.iterkeys():
 289             if not interface.endswith("-l"):
 290                 continue
 291             vlan, pp_name, logical = interface.split("-")
 292             uuid = vtep_ctl("get physical_port %s vlan_stats:%s"
 293                             % (pp_name, vlan))
 294             if not uuid:
 295                 continue
 296
 297             for (mapfrom, mapto) in stats_map.iteritems():
 298                 value = ovs_vsctl("get interface %s statistics:%s"
 299                                 % (interface, mapfrom)).strip('"')
 300                 vtep_ctl("set logical_binding_stats %s %s=%s"
 301                         % (uuid, mapto, value))
 302
 303     def run(self):
 304         self.update_local_macs()
 305         self.update_remote_macs()
 306         self.update_stats()
 307
 308 def add_binding(ps_name, binding, ls):
 309     vlog.info("adding binding %s" % binding)
 310
 311     vlan, pp_name = binding.split("-")
 312     pbinding = binding+"-p"
 313     lbinding = binding+"-l"
 314
 315     # Create a patch port that connects the VLAN+port to the lswitch.
 316     # Do them as two separate calls so if one side already exists, the
 317     # other side is created.
 318     ovs_vsctl("add-port %s %s "
 319               " -- set Interface %s type=patch options:peer=%s"
 320               % (ps_name, pbinding, pbinding, lbinding))
 321     ovs_vsctl("add-port %s %s "
 322               " -- set Interface %s type=patch options:peer=%s"
 323               % (ls.short_name, lbinding, lbinding, pbinding))
 324
 325     port_no = ovs_vsctl("get Interface %s ofport" % pp_name)
 326     patch_no = ovs_vsctl("get Interface %s ofport" % pbinding)
 327     vlan_ = vlan.lstrip('0')
 328     if vlan_:
 329         ovs_ofctl("add-flow %s in_port=%s,dl_vlan=%s,action=strip_vlan,%s"
 330                   % (ps_name, port_no, vlan_, patch_no))
 331         ovs_ofctl("add-flow %s in_port=%s,action=mod_vlan_vid:%s,%s"
 332                   % (ps_name, patch_no, vlan_, port_no))
 333     else:
 334         ovs_ofctl("add-flow %s in_port=%s,action=%s"
 335                   % (ps_name, port_no, patch_no))
 336         ovs_ofctl("add-flow %s in_port=%s,action=%s"
 337                   % (ps_name, patch_no, port_no))
 338
 339     # Create a logical_bindings_stats record.
 340     if not vlan_:
 341         vlan_ = "0"
 342     vtep_ctl("set physical_port %s vlan_stats:%s=@stats --\
 343             --id=@stats create logical_binding_stats packets_from_local=0"\
 344             % (pp_name, vlan_))
 345
 346     ls.add_lbinding(lbinding)
 347     Bindings[binding] = ls.name
 348
 349 def del_binding(ps_name, binding, ls):
 350     vlog.info("removing binding %s" % binding)
 351
 352     vlan, pp_name = binding.split("-")
 353     pbinding = binding+"-p"
 354     lbinding = binding+"-l"
 355
 356     port_no = ovs_vsctl("get Interface %s ofport" % pp_name)
 357     patch_no = ovs_vsctl("get Interface %s ofport" % pbinding)
 358     vlan_ = vlan.lstrip('0')
 359     if vlan_:
 360         ovs_ofctl("del-flows %s in_port=%s,dl_vlan=%s"
 361                   % (ps_name, port_no, vlan_))
 362         ovs_ofctl("del-flows %s in_port=%s" % (ps_name, patch_no))
 363     else:
 364         ovs_ofctl("del-flows %s in_port=%s" % (ps_name, port_no))
 365         ovs_ofctl("del-flows %s in_port=%s" % (ps_name, patch_no))
 366
 367     ls.del_lbinding(lbinding)
 368
 369     # Destroy the patch port that connects the VLAN+port to the lswitch
 370     ovs_vsctl("del-port %s %s -- del-port %s %s"
 371               % (ps_name, pbinding, ls.short_name, lbinding))
 372
 373     # Remove the record that links vlan with stats in logical_binding_stats.
 374     vtep_ctl("remove physical_port %s vlan_stats %s" % (pp_name, vlan))
 375
 376     del Bindings[binding]
 377
 378 def handle_physical(ps_name):
 379     # Gather physical ports except the patch ports we created
 380     ovs_ports = ovs_vsctl("list-ports %s" % ps_name).split()
 381     ovs_port_set = set([port for port in ovs_ports if port[-2:] != "-p"])
 382
 383     vtep_pp_set = set(vtep_ctl("list-ports %s" % ps_name).split())
 384
 385     for pp_name in ovs_port_set.difference(vtep_pp_set):
 386         vlog.info("adding %s to %s" % (pp_name, ps_name))
 387         vtep_ctl("add-port %s %s" % (ps_name, pp_name))
 388
 389     for pp_name in vtep_pp_set.difference(ovs_port_set):
 390         vlog.info("deleting %s from %s" % (pp_name, ps_name))
 391         vtep_ctl("del-port %s %s" % (ps_name, pp_name))
 392
 393     new_bindings = set()
 394     for pp_name in vtep_pp_set:
 395         binding_set = set(vtep_ctl("list-bindings %s %s"
 396                                    % (ps_name, pp_name)).splitlines())
 397
 398         for b in binding_set:
 399             vlan, ls_name = b.split()
 400             if ls_name not in Lswitches:
 401                 Lswitches[ls_name] = Logical_Switch(ls_name)
 402
 403             binding = "%s-%s" % (vlan, pp_name)
 404             ls = Lswitches[ls_name]
 405             new_bindings.add(binding)
 406
 407             if Bindings.has_key(binding):
 408                 if Bindings[binding] == ls_name:
 409                     continue
 410                 else:
 411                     del_binding(ps_name, binding, Lswitches[Bindings[binding]])
 412
 413             add_binding(ps_name, binding, ls)
 414
 415
 416     dead_bindings = set(Bindings.keys()).difference(new_bindings)
 417     for binding in dead_bindings:
 418         ls_name = Bindings[binding]
 419         ls = Lswitches[ls_name]
 420
 421         del_binding(ps_name, binding, ls)
 422
 423         if not len(ls.ports):
 424             ovs_vsctl("del-br %s" % Lswitches[ls_name].short_name)
 425             del Lswitches[ls_name]
 426
 427 def setup(ps_name):
 428     br_list = ovs_vsctl("list-br").split()
 429     if (ps_name not in br_list):
 430         ovs.util.ovs_fatal(0, "couldn't find OVS bridge %s" % ps_name, vlog)
 431
 432     call_prog("vtep-ctl", ["set", "physical_switch", ps_name,
 433                            'description="OVS VTEP Emulator"'])
 434
 435     tunnel_ips = vtep_ctl("get physical_switch %s tunnel_ips"
 436                           % ps_name).strip('[]"').split(", ")
 437     if len(tunnel_ips) != 1 or not tunnel_ips[0]:
 438         ovs.util.ovs_fatal(0, "exactly one 'tunnel_ips' should be set", vlog)
 439
 440     global Tunnel_Ip
 441     Tunnel_Ip = tunnel_ips[0]
 442
 443     ovs_ofctl("del-flows %s" % ps_name)
 444
 445     # Remove any logical bridges from the previous run
 446     for br in br_list:
 447         if ovs_vsctl("br-get-external-id %s vtep_logical_switch"
 448                      % br) == "true":
 449             # Remove the remote side of any logical switch
 450             ovs_ports = ovs_vsctl("list-ports %s" % br).split()
 451             for port in ovs_ports:
 452                 port_type = ovs_vsctl("get Interface %s type"
 453                                       % port).strip('"')
 454                 if port_type != "patch":
 455                     continue
 456
 457                 peer = ovs_vsctl("get Interface %s options:peer"
 458                                  % port).strip('"')
 459                 if (peer):
 460                     ovs_vsctl("del-port %s" % peer)
 461
 462             ovs_vsctl("del-br %s" % br)
 463
 464
 465 def main():
 466     parser = argparse.ArgumentParser()
 467     parser.add_argument("ps_name", metavar="PS-NAME",
 468                         help="Name of physical switch.")
 469     parser.add_argument("--root-prefix", metavar="DIR",
 470                         help="Use DIR as alternate root directory"
 471                         " (for testing).")
 472     parser.add_argument("--version", action="version",
 473                         version="%s %s" % (ovs.util.PROGRAM_NAME, VERSION))
 474
 475     ovs.vlog.add_args(parser)
 476     ovs.daemon.add_args(parser)
 477     args = parser.parse_args()
 478     ovs.vlog.handle_args(args)
 479     ovs.daemon.handle_args(args)
 480
 481     global root_prefix
 482     if args.root_prefix:
 483         root_prefix = args.root_prefix
 484
 485     ps_name = args.ps_name
 486
 487     ovs.daemon.daemonize()
 488
 489     ovs.unixctl.command_register("exit", "", 0, 0, unixctl_exit, None)
 490     error, unixctl = ovs.unixctl.server.UnixctlServer.create(None,
 491                                                              version=VERSION)
 492     if error:
 493         ovs.util.ovs_fatal(error, "could not create unixctl server", vlog)
 494
 495     setup(ps_name)
 496
 497     while True:
 498         unixctl.run()
 499         if exiting:
 500             break
 501
 502         handle_physical(ps_name)
 503
 504         for ls_name, ls in Lswitches.items():
 505             ls.run()
 506
 507         poller = ovs.poller.Poller()
 508         unixctl.wait(poller)
 509         poller.timer_wait(1000)
 510         poller.block()
 511
 512     unixctl.close()
 513
 514 if __name__ == '__main__':
 515     try:
 516         main()
 517     except SystemExit:
 518         # Let system.exit() calls complete normally
 519         raise
 520     except:
 521         vlog.exception("traceback")
 522         sys.exit(ovs.daemon.RESTART_EXIT_CODE)