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