src/nepi/resources/linux/tap.py

   1 #
   2 #    NEPI, a framework to manage network experiments
   3 #    Copyright (C) 2013 INRIA
   4 #
   5 #    This program is free software: you can redistribute it and/or modify
   6 #    it under the terms of the GNU General Public License as published by
   7 #    the Free Software Foundation, either version 3 of the License, or
   8 #    (at your option) any later version.
   9 #
  10 #    This program is distributed in the hope that it will be useful,
  11 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 #    GNU General Public License for more details.
  14 #
  15 #    You should have received a copy of the GNU General Public License
  16 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 #
  18 # Author: Alina Quereilhac <alina.quereilhac@inria.fr>
  19
  20 from nepi.execution.attribute import Attribute, Flags, Types
  21 from nepi.execution.resource import clsinit_copy, ResourceState
  22 from nepi.resources.linux.application import LinuxApplication
  23 from nepi.resources.linux.node import LinuxNode
  24 from nepi.util.timefuncs import tnow, tdiffsec
  25
  26 import os
  27 import time
  28
  29 PYTHON_VSYS_VERSION = "1.0"
  30
  31 @clsinit_copy
  32 class LinuxTap(LinuxApplication):
  33     _rtype = "linux::Tap"
  34     _help = "Creates a TAP device on a Linux host"
  35     _backend = "linux"
  36
  37     IFF_TUN = 0x0001
  38     IFF_TAP = 0x0002
  39
  40     @classmethod
  41     def _register_attributes(cls):
  42         ip = Attribute("ip", "IPv4 Address",
  43               flags = Flags.Design)
  44
  45         mac = Attribute("mac", "MAC Address",
  46                 flags = Flags.Design)
  47
  48         prefix = Attribute("prefix", "IPv4 network prefix",
  49                 flags = Flags.Design)
  50
  51         mtu = Attribute("mtu", "Maximum transmition unit for device",
  52                 type = Types.Integer)
  53
  54         devname = Attribute("deviceName",
  55                 "Name of the network interface (e.g. eth0, wlan0, etc)",
  56                 flags = Flags.NoWrite)
  57
  58         up = Attribute("up", "Link up",
  59                 type = Types.Bool)
  60
  61         pointopoint = Attribute("pointopoint", "Peer IP address",
  62                 flags = Flags.Design)
  63
  64         txqueuelen = Attribute("txqueuelen", "Length of transmission queue",
  65                 flags = Flags.Design)
  66
  67         txqueuelen = Attribute("txqueuelen", "Length of transmission queue",
  68                 flags = Flags.Design)
  69
  70         gre_key = Attribute("greKey",
  71                 "GRE key to be used to configure GRE tunnel",
  72                 default = "1",
  73                 flags = Flags.Design)
  74
  75         gre_remote = Attribute("greRemote",
  76                 "Public IP of remote endpoint for GRE tunnel",
  77                 flags = Flags.Design)
  78
  79         pi = Attribute("pi", "Add PI (protocol information) header",
  80                 default = False,
  81                 type = Types.Bool)
  82
  83         tear_down = Attribute("tearDown",
  84                 "Bash script to be executed before releasing the resource",
  85                 flags = Flags.Design)
  86
  87         cls._register_attribute(ip)
  88         cls._register_attribute(mac)
  89         cls._register_attribute(prefix)
  90         cls._register_attribute(mtu)
  91         cls._register_attribute(devname)
  92         cls._register_attribute(up)
  93         cls._register_attribute(pointopoint)
  94         cls._register_attribute(txqueuelen)
  95         cls._register_attribute(gre_key)
  96         cls._register_attribute(gre_remote)
  97         cls._register_attribute(pi)
  98         cls._register_attribute(tear_down)
  99
 100     def __init__(self, ec, guid):
 101         super(LinuxTap, self).__init__(ec, guid)
 102         self._home = "tap-%s" % self.guid
 103         self._gre_enabled = False
 104         self._tunnel_mode = False
 105
 106     @property
 107     def node(self):
 108         node = self.get_connected(LinuxNode.get_rtype())
 109         if node: return node[0]
 110         raise RuntimeError, "linux::TAP/TUN devices must be connected to a linux::Node"
 111
 112     @property
 113     def gre_enabled(self):
 114         if not self._gre_enabled:
 115             from nepi.resources.linux.gretunnel import LinuxGRETunnel
 116             gre = self.get_connected(LinuxGRETunnel.get_rtype())
 117             if gre: self._gre_enabled = True
 118
 119         return self._gre_enabled
 120
 121     @property
 122     def tunnel_mode(self):
 123         if not self._tunnel_mode:
 124             from nepi.resources.linux.tunnel import LinuxTunnel
 125             tunnel = self.get_connected(LinuxTunnel.get_rtype())
 126             if tunnel: self._tunnel_mode = True
 127
 128         return self._tunnel_mode
 129
 130     def upload_sources(self):
 131         scripts = []
 132
 133         # udp-connect python script
 134         udp_connect = os.path.join(os.path.dirname(__file__), "scripts",
 135                 "linux-udp-connect.py")
 136
 137         scripts.append(udp_connect)
 138
 139         # tunnel creation python script
 140         tunchannel = os.path.join(os.path.dirname(__file__), "scripts",
 141                 "tunchannel.py")
 142
 143         scripts.append(tunchannel)
 144
 145         # Upload scripts
 146         scripts = ";".join(scripts)
 147
 148         self.node.upload(scripts,
 149                 os.path.join(self.node.src_dir),
 150                 overwrite = False)
 151
 152         # upload stop.sh script
 153         stop_command = self.replace_paths(self._stop_command)
 154
 155         self.node.upload(stop_command,
 156                 os.path.join(self.app_home, "stop.sh"),
 157                 text = True,
 158                 # Overwrite file every time.
 159                 # The stop.sh has the path to the socket, which should change
 160                 # on every experiment run.
 161                 overwrite = True)
 162
 163     def upload_start_command(self):
 164         # If GRE mode is enabled, TAP creation is delayed until the
 165         # tunnel is established
 166         if not self.tunnel_mode:
 167             # We want to make sure the device is up and running
 168             # before the deploy is over, so we execute the
 169             # start script now and wait until it finishes.
 170             command = self.get("command")
 171             command = self.replace_paths(command)
 172
 173             shfile = os.path.join(self.app_home, "start.sh")
 174             self.node.run_and_wait(command, self.run_home,
 175                 shfile = shfile,
 176                 overwrite = True)
 177
 178     def do_deploy(self):
 179         if not self.node or self.node.state < ResourceState.PROVISIONED:
 180             self.ec.schedule(self.reschedule_delay, self.deploy)
 181         else:
 182             if not self.get("deviceName"):
 183                 self.set("deviceName", "%s%d" % (self.vif_prefix, self.guid))
 184
 185             if not self.get("command"):
 186                 self.set("command", self._start_command)
 187
 188             self.do_discover()
 189             self.do_provision()
 190
 191             self.set_ready()
 192
 193     def do_start(self):
 194         if self.state == ResourceState.READY:
 195             command = self.get("command")
 196             self.info("Starting command '%s'" % command)
 197
 198             self.set_started()
 199         else:
 200             msg = " Failed to execute command '%s'" % command
 201             self.error(msg, out, err)
 202             raise RuntimeError, msg
 203
 204     def do_stop(self):
 205         command = self.get('command') or ''
 206
 207         if self.state == ResourceState.STARTED:
 208             self.info("Stopping command '%s'" % command)
 209
 210             command = "bash %s" % os.path.join(self.app_home, "stop.sh")
 211             (out, err), proc = self.execute_command(command,
 212                     blocking = True)
 213
 214             if err:
 215                 msg = " Failed to stop command '%s' " % command
 216                 self.error(msg, out, err)
 217
 218             self.set_stopped()
 219
 220     @property
 221     def state(self):
 222         state_check_delay = 0.5
 223         if self._state == ResourceState.STARTED and \
 224                 tdiffsec(tnow(), self._last_state_check) > state_check_delay:
 225
 226             if self.get("deviceName"):
 227                 (out, err), proc = self.node.execute("ip a")
 228
 229                 if out.strip().find(self.get("deviceName")) == -1:
 230                     # tap is not running is not running (socket not found)
 231                     self.set_stopped()
 232
 233             self._last_state_check = tnow()
 234
 235         return self._state
 236
 237     def do_release(self):
 238         # Node needs to wait until all associated RMs are released
 239         # to be released
 240         from nepi.resources.linux.tunnel import LinuxTunnel
 241         rms = self.get_connected(LinuxTunnel.get_rtype())
 242
 243         for rm in rms:
 244             if rm.state < ResourceState.STOPPED:
 245                 self.ec.schedule(self.reschedule_delay, self.release)
 246                 return
 247
 248         super(LinuxTap, self).do_release()
 249
 250     def gre_connect(self, remote_endpoint, connection_app_home,
 251             connection_run_home):
 252         gre_connect_command = self._gre_connect_command(
 253                 remote_endpoint, connection_run_home)
 254
 255         # upload command to connect.sh script
 256         shfile = os.path.join(connection_app_home, "gre-connect.sh")
 257         self.node.upload_command(gre_connect_command,
 258                 shfile = shfile,
 259                 overwrite = False)
 260
 261         # invoke connect script
 262         cmd = "bash %s" % shfile
 263         (out, err), proc = self.node.run(cmd, connection_run_home)
 264
 265         # check if execution errors occurred
 266         msg = " Failed to connect endpoints "
 267
 268         if proc.poll() or err:
 269             self.error(msg, out, err)
 270             raise RuntimeError, msg
 271
 272         # Wait for pid file to be generated
 273         pid, ppid = self.node.wait_pid(connection_run_home)
 274
 275         # If the process is not running, check for error information
 276         # on the remote machine
 277         if not pid or not ppid:
 278             (out, err), proc = self.node.check_errors(connection_run_home)
 279             # Out is what was written in the stderr file
 280             if err:
 281                 msg = " Failed to start command '%s' " % command
 282                 self.error(msg, out, err)
 283                 raise RuntimeError, msg
 284
 285         return True
 286
 287     def initiate_udp_connection(self, remote_endpoint, connection_app_home,
 288             connection_run_home, cipher, cipher_key, bwlimit, txqueuelen):
 289         port = self.udp_connect(remote_endpoint, connection_app_home,
 290             connection_run_home, cipher, cipher_key, bwlimit, txqueuelen)
 291         return port
 292
 293     def udp_connect(self, remote_endpoint, connection_app_home,
 294             connection_run_home, cipher, cipher_key, bwlimit, txqueuelen):
 295         udp_connect_command = self._udp_connect_command(
 296                 remote_endpoint, connection_run_home,
 297                 cipher, cipher_key, bwlimit, txqueuelen)
 298
 299         # upload command to connect.sh script
 300         shfile = os.path.join(self.app_home, "udp-connect.sh")
 301         self.node.upload_command(udp_connect_command,
 302                 shfile = shfile,
 303                 overwrite = False)
 304
 305         # invoke connect script
 306         cmd = "bash %s" % shfile
 307         (out, err), proc = self.node.run(cmd, self.run_home)
 308
 309         # check if execution errors occurred
 310         msg = "Failed to connect endpoints "
 311
 312         if proc.poll():
 313             self.error(msg, out, err)
 314             raise RuntimeError, msg
 315
 316         # Wait for pid file to be generated
 317         self._pid, self._ppid = self.node.wait_pid(self.run_home)
 318
 319         # If the process is not running, check for error information
 320         # on the remote machine
 321         if not self._pid or not self._ppid:
 322             (out, err), proc = self.node.check_errors(self.run_home)
 323             # Out is what was written in the stderr file
 324             if err:
 325                 msg = " Failed to start command '%s' " % command
 326                 self.error(msg, out, err)
 327                 raise RuntimeError, msg
 328
 329         port = self.wait_local_port()
 330
 331         return port
 332
 333     def _udp_connect_command(self, remote_endpoint, connection_run_home,
 334             cipher, cipher_key, bwlimit, txqueuelen):
 335
 336         # Set the remote endpoint to the IP of the device
 337         self.set("pointopoint", remote_endpoint.get("ip"))
 338
 339         # Planetlab TAPs always use PI headers
 340         from nepi.resources.planetlab.tap import PlanetlabTap
 341         if self.is_rm_instance(PlanetlabTap.get_rtype()):
 342             self.set("pi", True)
 343
 344         # Public IP of the remote NODE to stablish tunnel
 345         remote_ip = remote_endpoint.node.get("ip")
 346
 347         local_port_file = os.path.join(self.run_home,
 348                 "local_port")
 349
 350         remote_port_file = os.path.join(self.run_home,
 351                 "remote_port")
 352
 353         ret_file = os.path.join(self.run_home,
 354                 "ret_file")
 355
 356         # Generate UDP connect command
 357         # Use the start command to configure TAP with peer info
 358         start_command = self._start_command
 359
 360         command = ["( "]
 361         command.append(start_command)
 362
 363         # Use pl-vid-udp-connect.py to stablish the tunnel between endpoints
 364         command.append(") & (")
 365         command.append("sudo -S")
 366         command.append("PYTHONPATH=$PYTHONPATH:${SRC}")
 367         command.append("python ${SRC}/linux-udp-connect.py")
 368         command.append("-N %s" % self.get("deviceName"))
 369         command.append("-t %s" % self.vif_type)
 370         if self.get("pi"):
 371             command.append("-p")
 372         command.append("-l %s " % local_port_file)
 373         command.append("-r %s " % remote_port_file)
 374         command.append("-H %s " % remote_ip)
 375         command.append("-R %s " % ret_file)
 376         if cipher:
 377             command.append("-c %s " % cipher)
 378         if cipher_key:
 379             command.append("-k %s " % cipher_key)
 380         if txqueuelen:
 381             command.append("-q %s " % txqueuelen)
 382         if bwlimit:
 383             command.append("-b %s " % bwlimit)
 384
 385         command.append(")")
 386
 387         command = " ".join(command)
 388         command = self.replace_paths(command)
 389
 390         return command
 391
 392     def _gre_connect_command(self, remote_endpoint, connection_run_home):
 393         # Set the remote endpoint to (private) device IP
 394         self.set("pointopoint", remote_endpoint.get("ip"))
 395         ## public node IP
 396         self.set("greRemote", remote_endpoint.node.get("ip"))
 397
 398         # Generate GRE connect command
 399         command = ["("]
 400         command.append(self._stop_command)
 401         command.append(") ; (")
 402         command.append(self._start_gre_command)
 403         command.append(")")
 404
 405         command = " ".join(command)
 406         command = self.replace_paths(command)
 407
 408         return command
 409
 410     def establish_udp_connection(self, remote_endpoint, port):
 411         # upload remote port number to file
 412         rem_port = "%s\n" % port
 413         self.node.upload(rem_port,
 414                 os.path.join(self.run_home, "remote_port"),
 415                 text = True,
 416                 overwrite = False)
 417
 418     def verify_connection(self):
 419         self.wait_result()
 420
 421     def terminate_connection(self):
 422         if  self._pid and self._ppid:
 423             (out, err), proc = self.node.kill(self._pid, self._ppid,
 424                     sudo = True)
 425
 426             # check if execution errors occurred
 427             if proc.poll() and err:
 428                 msg = " Failed to Kill the Tap"
 429                 self.error(msg, out, err)
 430                 raise RuntimeError, msg
 431
 432     def check_status(self):
 433         return self.node.status(self._pid, self._ppid)
 434
 435     def wait_local_port(self):
 436         """ Waits until the local_port file for the endpoint is generated,
 437         and returns the port number
 438
 439         """
 440         return self.wait_file("local_port")
 441
 442     def wait_result(self):
 443         """ Waits until the return code file for the endpoint is generated
 444
 445         """
 446         return self.wait_file("ret_file")
 447
 448     def wait_file(self, filename):
 449         """ Waits until file on endpoint is generated """
 450         result = None
 451         delay = 1.0
 452
 453         for i in xrange(20):
 454             (out, err), proc = self.node.check_output(
 455                     self.run_home, filename)
 456             if out:
 457                 result = out.strip()
 458                 break
 459             else:
 460                 time.sleep(delay)
 461                 delay = delay * 1.5
 462         else:
 463             msg = "Couldn't retrieve %s" % filename
 464             self.error(msg, out, err)
 465             raise RuntimeError, msg
 466
 467         return result
 468
 469     @property
 470     def _start_command(self):
 471         command = []
 472         if not self.gre_enabled:
 473             # Make sure to clean TAP if it existed
 474             stop_command = self._stop_command
 475
 476             start_command = []
 477             start_command.append("sudo -S ip tuntap add %s mode %s %s" % (
 478                 self.get("deviceName"),
 479                 self.vif_prefix,
 480                 "pi" if self.get("pi") else ""))
 481             start_command.append("sudo -S ip link set %s up" % self.get("deviceName"))
 482             start_command.append("sudo -S ip addr add %s/%s dev %s" % (
 483                 self.get("ip"),
 484                 self.get("prefix"),
 485                 self.get("deviceName"),
 486                 ))
 487
 488             start_command = ";".join(start_command)
 489
 490             command.append("(")
 491             command.append(stop_command)
 492             command.append(") ; (")
 493             command.append(start_command)
 494             command.append(")")
 495
 496         return " ".join(command)
 497
 498     @property
 499     def _stop_command(self):
 500         command = []
 501         command.append("sudo -S ip link set %s down" % self.get("deviceName"))
 502         command.append("sudo -S ip link del %s" % self.get("deviceName"))
 503
 504         return ";".join(command)
 505
 506     @property
 507     def _start_gre_command(self):
 508         command = []
 509         command.append("sudo -S modprobe ip_gre")
 510         command.append("sudo -S ip link add %s type gre remote %s local %s ttl 64 csum key %s" % (
 511                 self.get("deviceName"),
 512                 self.get("greRemote"),
 513                 self.node.get("ip"),
 514                 self.get("greKey")
 515             ))
 516         command.append("sudo -S ip addr add %s/%s peer %s/%s dev %s" % (
 517                 self.get("ip"),
 518                 self.get("prefix"),
 519                 self.get("pointopoint"),
 520                 self.get("prefix"),
 521                 self.get("deviceName"),
 522                 ))
 523         command.append("sudo -S ip link set %s up " % self.get("deviceName"))
 524
 525         return ";".join(command)
 526
 527     @property
 528     def vif_type(self):
 529         return "IFF_TAP"
 530
 531     @property
 532     def vif_type_flag(self):
 533         return LinuxTap.IFF_TAP
 534
 535     @property
 536     def vif_prefix(self):
 537         return "tap"
 538
 539     def sock_name(self):
 540         return os.path.join(self.run_home, "tap.sock")
 541
 542     def valid_connection(self, guid):
 543         # TODO: Validate!
 544         return True
 545