#
# NEPI, a framework to manage network experiments
# Copyright (C) 2013 INRIA
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see .
#
# Author: Alina Quereilhac
from nepi.execution.attribute import Attribute, Flags, Types
from nepi.execution.resource import clsinit_copy, ResourceState, \
reschedule_delay
from nepi.resources.linux.application import LinuxApplication
from nepi.resources.linux.node import LinuxNode
from nepi.util.timefuncs import tnow, tdiffsec
import os
import time
PYTHON_VSYS_VERSION = "1.0"
@clsinit_copy
class LinuxTap(LinuxApplication):
_rtype = "LinuxTap"
_help = "Creates a TAP device on a Linux host"
_backend = "linux"
@classmethod
def _register_attributes(cls):
endpoint_ip = Attribute("endpoint_ip", "IPv4 Address",
flags = Flags.Design)
mac = Attribute("mac", "MAC Address",
flags = Flags.Design)
endpoint_prefix = Attribute("endpoint_prefix", "IPv4 network prefix",
type = Types.Integer,
flags = Flags.Design)
mtu = Attribute("mtu", "Maximum transmition unit for device",
type = Types.Integer)
devname = Attribute("deviceName",
"Name of the network interface (e.g. eth0, wlan0, etc)",
flags = Flags.NoWrite)
up = Attribute("up", "Link up",
type = Types.Bool)
pointopoint = Attribute("pointopoint", "Peer IP address",
flags = Flags.Design)
txqueuelen = Attribute("txqueuelen", "Length of transmission queue",
flags = Flags.Design)
txqueuelen = Attribute("txqueuelen", "Length of transmission queue",
flags = Flags.Design)
gre_key = Attribute("greKey",
"GRE key to be used to configure GRE tunnel",
default = "1",
flags = Flags.Design)
gre_remote = Attribute("greRemote",
"Public IP of remote endpoint for GRE tunnel",
flags = Flags.Design)
pi = Attribute("pi", "Add PI (protocol information) header",
default = False,
type = Types.Bool)
tear_down = Attribute("tearDown",
"Bash script to be executed before releasing the resource",
flags = Flags.Design)
cls._register_attribute(endpoint_ip)
cls._register_attribute(mac)
cls._register_attribute(endpoint_prefix)
cls._register_attribute(mtu)
cls._register_attribute(devname)
cls._register_attribute(up)
cls._register_attribute(pointopoint)
cls._register_attribute(txqueuelen)
cls._register_attribute(gre_key)
cls._register_attribute(gre_remote)
cls._register_attribute(pi)
cls._register_attribute(tear_down)
def __init__(self, ec, guid):
super(LinuxTap, self).__init__(ec, guid)
self._home = "tap-%s" % self.guid
self._gre_enabled = False
self._tunnel_mode = False
@property
def node(self):
node = self.get_connected(LinuxNode.get_rtype())
if node: return node[0]
raise RuntimeError, "TAP/TUN devices must be connected to Node"
@property
def gre_enabled(self):
if not self._gre_enabled:
from nepi.resources.linux.gretunnel import LinuxGRETunnel
gre = self.get_connected(LinuxGRETunnel.get_rtype())
if gre: self._gre_enabled = True
return self._gre_enabled
@property
def tunnel_mode(self):
if not self._tunnel_mode:
from nepi.resources.linux.tunnel import LinuxTunnel
tunnel = self.get_connected(LinuxTunnel.get_rtype())
if tunnel: self._tunnel_mode = True
return self._tunnel_mode
def upload_sources(self):
scripts = []
# udp-connect python script
udp_connect = os.path.join(os.path.dirname(__file__), "scripts",
"linux-udp-connect.py")
scripts.append(udp_connect)
# tunnel creation python script
tunchannel = os.path.join(os.path.dirname(__file__), "scripts",
"tunchannel.py")
scripts.append(tunchannel)
# Upload scripts
scripts = ";".join(scripts)
self.node.upload(scripts,
os.path.join(self.node.src_dir),
overwrite = False)
# upload stop.sh script
stop_command = self.replace_paths(self._stop_command)
self.node.upload(stop_command,
os.path.join(self.app_home, "stop.sh"),
text = True,
# Overwrite file every time.
# The stop.sh has the path to the socket, which should change
# on every experiment run.
overwrite = True)
def upload_start_command(self):
# If GRE mode is enabled, TAP creation is delayed until the
# tunnel is established
if not self.tunnel_mode:
# We want to make sure the device is up and running
# before the deploy is over, so we execute the
# start script now and wait until it finishes.
command = self.get("command")
command = self.replace_paths(command)
shfile = os.path.join(self.app_home, "start.sh")
self.node.run_and_wait(command, self.run_home,
shfile = shfile,
overwrite = True)
def do_deploy(self):
if not self.node or self.node.state < ResourceState.PROVISIONED:
self.ec.schedule(reschedule_delay, self.deploy)
else:
if not self.get("deviceName"):
self.set("deviceName", "%s%d" % (self.vif_prefix, self.guid))
if not self.get("command"):
self.set("command", self._start_command)
self.do_discover()
self.do_provision()
self.set_ready()
def do_start(self):
if self.state == ResourceState.READY:
command = self.get("command")
self.info("Starting command '%s'" % command)
self.set_started()
else:
msg = " Failed to execute command '%s'" % command
self.error(msg, out, err)
raise RuntimeError, msg
def do_stop(self):
command = self.get('command') or ''
if self.state == ResourceState.STARTED:
self.info("Stopping command '%s'" % command)
command = "bash %s" % os.path.join(self.app_home, "stop.sh")
(out, err), proc = self.execute_command(command,
blocking = True)
if err:
msg = " Failed to stop command '%s' " % command
self.error(msg, out, err)
self.set_stopped()
@property
def state(self):
state_check_delay = 0.5
if self._state == ResourceState.STARTED and \
tdiffsec(tnow(), self._last_state_check) > state_check_delay:
if self.get("deviceName"):
(out, err), proc = self.node.execute("ifconfig")
if out.strip().find(self.get("deviceName")) == -1:
# tap is not running is not running (socket not found)
self.set_stopped()
self._last_state_check = tnow()
return self._state
def do_release(self):
# Node needs to wait until all associated RMs are released
# to be released
from nepi.resources.linux.tunnel import LinuxTunnel
rms = self.get_connected(LinuxTunnel.get_rtype())
for rm in rms:
if rm.state < ResourceState.STOPPED:
self.ec.schedule(reschedule_delay, self.release)
return
super(LinuxTap, self).do_release()
def gre_connect(self, remote_endpoint, connection_app_home,
connection_run_home):
gre_connect_command = self._gre_connect_command(
remote_endpoint, connection_run_home)
# upload command to connect.sh script
shfile = os.path.join(connection_app_home, "gre-connect.sh")
self.node.upload_command(gre_connect_command,
shfile = shfile,
overwrite = False)
# invoke connect script
cmd = "bash %s" % shfile
(out, err), proc = self.node.run(cmd, connection_run_home)
# check if execution errors occurred
msg = " Failed to connect endpoints "
if proc.poll() or err:
self.error(msg, out, err)
raise RuntimeError, msg
# Wait for pid file to be generated
pid, ppid = self.node.wait_pid(connection_run_home)
# If the process is not running, check for error information
# on the remote machine
if not pid or not ppid:
(out, err), proc = self.node.check_errors(connection_run_home)
# Out is what was written in the stderr file
if err:
msg = " Failed to start command '%s' " % command
self.error(msg, out, err)
raise RuntimeError, msg
return True
def initiate_udp_connection(self, remote_endpoint, connection_app_home,
connection_run_home, cipher, cipher_key, bwlimit, txqueuelen):
port = self.udp_connect(remote_endpoint, connection_app_home,
connection_run_home, cipher, cipher_key, bwlimit, txqueuelen)
return port
def udp_connect(self, remote_endpoint, connection_app_home,
connection_run_home, cipher, cipher_key, bwlimit, txqueuelen):
udp_connect_command = self._udp_connect_command(
remote_endpoint, connection_run_home,
cipher, cipher_key, bwlimit, txqueuelen)
# upload command to connect.sh script
shfile = os.path.join(self.app_home, "udp-connect.sh")
self.node.upload_command(udp_connect_command,
shfile = shfile,
overwrite = False)
# invoke connect script
cmd = "bash %s" % shfile
(out, err), proc = self.node.run(cmd, self.run_home)
# check if execution errors occurred
msg = "Failed to connect endpoints "
if proc.poll():
self.error(msg, out, err)
raise RuntimeError, msg
# Wait for pid file to be generated
self._pid, self._ppid = self.node.wait_pid(self.run_home)
# If the process is not running, check for error information
# on the remote machine
if not self._pid or not self._ppid:
(out, err), proc = self.node.check_errors(self.run_home)
# Out is what was written in the stderr file
if err:
msg = " Failed to start command '%s' " % command
self.error(msg, out, err)
raise RuntimeError, msg
port = self.wait_local_port()
return port
def _udp_connect_command(self, remote_endpoint, connection_run_home,
cipher, cipher_key, bwlimit, txqueuelen):
# Set the remote endpoint
self.set("pointopoint", remote_endpoint.get("endpoint_ip"))
# Planetlab TAPs always use PI headers
from nepi.resources.planetlab.tap import PlanetlabTap
if self.is_rm_instance(PlanetlabTap.get_rtype()):
self.set("pi", True)
remote_ip = remote_endpoint.node.get("ip")
local_port_file = os.path.join(self.run_home,
"local_port")
remote_port_file = os.path.join(self.run_home,
"remote_port")
ret_file = os.path.join(self.run_home,
"ret_file")
# Generate UDP connect command
# Use the start command to configure TAP with peer info
start_command = self._start_command
command = ["( "]
command.append(start_command)
# Use pl-vid-udp-connect.py to stablish the tunnel between endpoints
command.append(") & (")
command.append("sudo -S")
command.append("PYTHONPATH=$PYTHONPATH:${SRC}")
command.append("python ${SRC}/linux-udp-connect.py")
command.append("-N %s" % self.get("deviceName"))
command.append("-t %s" % self.vif_type)
if self.get("pi"):
command.append("-p")
command.append("-l %s " % local_port_file)
command.append("-r %s " % remote_port_file)
command.append("-H %s " % remote_ip)
command.append("-R %s " % ret_file)
if cipher:
command.append("-c %s " % cipher)
if cipher_key:
command.append("-k %s " % cipher_key)
if txqueuelen:
command.append("-q %s " % txqueuelen)
if bwlimit:
command.append("-b %s " % bwlimit)
command.append(")")
command = " ".join(command)
command = self.replace_paths(command)
return command
def _gre_connect_command(self, remote_endpoint, connection_run_home):
# Set the remote endpoint
self.set("pointopoint", remote_endpoint.get("endpoint_ip"))
self.set("greRemote", remote_endpoint.node.get("ip"))
# Generate GRE connect command
command = ["("]
command.append(self._stop_command)
command.append(") ; (")
command.append(self._start_gre_command)
command.append(")")
command = " ".join(command)
command = self.replace_paths(command)
return command
def establish_udp_connection(self, remote_endpoint, port):
# upload remote port number to file
rem_port = "%s\n" % port
self.node.upload(rem_port,
os.path.join(self.run_home, "remote_port"),
text = True,
overwrite = False)
def verify_connection(self):
self.wait_result()
def terminate_connection(self):
if self._pid and self._ppid:
(out, err), proc = self.node.kill(self._pid, self._ppid,
sudo = True)
# check if execution errors occurred
if proc.poll() and err:
msg = " Failed to Kill the Tap"
self.error(msg, out, err)
raise RuntimeError, msg
def check_status(self):
return self.node.status(self._pid, self._ppid)
def wait_local_port(self):
""" Waits until the local_port file for the endpoint is generated,
and returns the port number
"""
return self.wait_file("local_port")
def wait_result(self):
""" Waits until the return code file for the endpoint is generated
"""
return self.wait_file("ret_file")
def wait_file(self, filename):
""" Waits until file on endpoint is generated """
result = None
delay = 1.0
for i in xrange(20):
(out, err), proc = self.node.check_output(
self.run_home, filename)
if out:
result = out.strip()
break
else:
time.sleep(delay)
delay = delay * 1.5
else:
msg = "Couldn't retrieve %s" % filename
self.error(msg, out, err)
raise RuntimeError, msg
return result
@property
def _start_command(self):
command = []
if not self.gre_enabled:
# Make sure to clean TAP if it existed
stop_command = self._stop_command
start_command = []
start_command.append("sudo -S ip tuntap add %s mode %s %s" % (
self.get("deviceName"),
self.vif_prefix,
"pi" if self.get("pi") else ""))
start_command.append("sudo -S ip link set %s up" % self.get("deviceName"))
start_command.append("sudo -S ip addr add %s/%d dev %s" % (
self.get("endpoint_ip"),
self.get("endpoint_prefix"),
self.get("deviceName"),
))
start_command = ";".join(start_command)
command.append("(")
command.append(stop_command)
command.append(") ; (")
command.append(start_command)
command.append(")")
return " ".join(command)
@property
def _stop_command(self):
command = []
command.append("sudo -S ip link set %s down" % self.get("deviceName"))
command.append("sudo -S ip link del %s" % self.get("deviceName"))
return ";".join(command)
@property
def _start_gre_command(self):
command = []
command.append("sudo -S modprobe ip_gre")
command.append("sudo -S ip link add %s type gre remote %s local %s ttl 64 csum key %s" % (
self.get("deviceName"),
self.get("greRemote"),
self.node.get("ip"),
self.get("greKey")
))
command.append("sudo -S ip addr add %s/%d peer %s/%d dev %s" % (
self.get("endpoint_ip"),
self.get("endpoint_prefix"),
self.get("pointopoint"),
self.get("endpoint_prefix"),
self.get("deviceName"),
))
command.append("sudo -S ip link set %s up " % self.get("deviceName"))
return ";".join(command)
@property
def vif_type(self):
return "IFF_TAP"
@property
def vif_prefix(self):
return "tap"
def sock_name(self):
return os.path.join(self.run_home, "tap.sock")
def valid_connection(self, guid):
# TODO: Validate!
return True