#
# 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.util.sshfuncs import ProcStatus
from nepi.util.timefuncs import tnow, tdiffsec
import os
import socket
import time
@clsinit_copy
class UdpTunnel(LinuxApplication):
_rtype = "UdpTunnel"
_help = "Constructs a tunnel between two Linux endpoints using a UDP connection "
_backend = "linux"
@classmethod
def _register_attributes(cls):
cipher = Attribute("cipher",
"Cipher to encript communication. "
"One of PLAIN, AES, Blowfish, DES, DES3. ",
default = None,
allowed = ["PLAIN", "AES", "Blowfish", "DES", "DES3"],
type = Types.Enumerate,
flags = Flags.Design)
cipher_key = Attribute("cipherKey",
"Specify a symmetric encryption key with which to protect "
"packets across the tunnel. python-crypto must be installed "
"on the system." ,
flags = Flags.Design)
txqueuelen = Attribute("txQueueLen",
"Specifies the interface's transmission queue length. "
"Defaults to 1000. ",
type = Types.Integer,
flags = Flags.Design)
bwlimit = Attribute("bwLimit",
"Specifies the interface's emulated bandwidth in bytes "
"per second.",
type = Types.Integer,
flags = Flags.Design)
cls._register_attribute(cipher)
cls._register_attribute(cipher_key)
cls._register_attribute(txqueuelen)
cls._register_attribute(bwlimit)
def __init__(self, ec, guid):
super(UdpTunnel, self).__init__(ec, guid)
self._home = "udp-tunnel-%s" % self.guid
self._pid1 = None
self._ppid1 = None
self._pid2 = None
self._ppid2 = None
def log_message(self, msg):
return " guid %d - tunnel %s - %s - %s " % (self.guid,
self.endpoint1.node.get("hostname"),
self.endpoint2.node.get("hostname"),
msg)
def get_endpoints(self):
""" Returns the list of RM that are endpoints to the tunnel
"""
connected = []
for guid in self.connections:
rm = self.ec.get_resource(guid)
if hasattr(rm, "udp_connect_command"):
connected.append(rm)
return connected
@property
def endpoint1(self):
endpoints = self.get_endpoints()
if endpoints: return endpoints[0]
return None
@property
def endpoint2(self):
endpoints = self.get_endpoints()
if endpoints and len(endpoints) > 1: return endpoints[1]
return None
def app_home(self, endpoint):
return os.path.join(endpoint.node.exp_home, self._home)
def run_home(self, endpoint):
return os.path.join(self.app_home(endpoint), self.ec.run_id)
def udp_connect(self, endpoint, remote_ip):
# Get udp connect command
local_port_file = os.path.join(self.run_home(endpoint),
"local_port")
remote_port_file = os.path.join(self.run_home(endpoint),
"remote_port")
ret_file = os.path.join(self.run_home(endpoint),
"ret_file")
cipher = self.get("cipher")
cipher_key = self.get("cipherKey")
bwlimit = self.get("bwLimit")
txqueuelen = self.get("txQueueLen")
udp_connect_command = endpoint.udp_connect_command(
remote_ip, local_port_file, remote_port_file,
ret_file, cipher, cipher_key, bwlimit, txqueuelen)
# upload command to connect.sh script
shfile = os.path.join(self.app_home(endpoint), "udp-connect.sh")
endpoint.node.upload(udp_connect_command,
shfile,
text = True,
overwrite = False)
# invoke connect script
cmd = "bash %s" % shfile
(out, err), proc = endpoint.node.run(cmd, self.run_home(endpoint))
# 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
pid, ppid = endpoint.node.wait_pid(self.run_home(endpoint))
# If the process is not running, check for error information
# on the remote machine
if not pid or not ppid:
(out, err), proc = endpoint.node.check_errors(self.run_home(endpoint))
# 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
# wait until port is written to file
port = self.wait_local_port(endpoint)
return (port, pid, ppid)
def do_provision(self):
# create run dir for tunnel on each node
self.endpoint1.node.mkdir(self.run_home(self.endpoint1))
self.endpoint2.node.mkdir(self.run_home(self.endpoint2))
# Invoke connect script in endpoint 1
remote_ip1 = socket.gethostbyname(self.endpoint2.node.get("hostname"))
(port1, self._pid1, self._ppid1) = self.udp_connect(self.endpoint1,
remote_ip1)
# Invoke connect script in endpoint 2
remote_ip2 = socket.gethostbyname(self.endpoint1.node.get("hostname"))
(port2, self._pid2, self._ppid2) = self.udp_connect(self.endpoint2,
remote_ip2)
# upload file with port 2 to endpoint 1
self.upload_remote_port(self.endpoint1, port2)
# upload file with port 1 to endpoint 2
self.upload_remote_port(self.endpoint2, port1)
# check if connection was successful on both sides
self.wait_result(self.endpoint1)
self.wait_result(self.endpoint2)
self.info("Provisioning finished")
self.set_provisioned()
def do_deploy(self):
if (not self.endpoint1 or self.endpoint1.state < ResourceState.READY) or \
(not self.endpoint2 or self.endpoint2.state < ResourceState.READY):
self.ec.schedule(reschedule_delay, self.deploy)
else:
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):
""" Stops application execution
"""
if self.state == ResourceState.STARTED:
self.info("Stopping tunnel")
# Only try to kill the process if the pid and ppid
# were retrieved
if self._pid1 and self._ppid1 and self._pid2 and self._ppid2:
(out1, err1), proc1 = self.endpoint1.node.kill(self._pid1,
self._ppid1, sudo = True)
(out2, err2), proc2 = self.endpoint2.node.kill(self._pid2,
self._ppid2, sudo = True)
if err1 or err2 or proc1.poll() or proc2.poll():
# check if execution errors occurred
msg = " Failed to STOP tunnel"
self.error(msg, err1, err2)
raise RuntimeError, msg
self.set_stopped()
@property
def state(self):
""" Returns the state of the application
"""
if self._state == ResourceState.STARTED:
# In order to avoid overwhelming the remote host and
# the local processor with too many ssh queries, the state is only
# requested every 'state_check_delay' seconds.
state_check_delay = 0.5
if tdiffsec(tnow(), self._last_state_check) > state_check_delay:
if self._pid1 and self._ppid1 and self._pid2 and self._ppid2:
# Make sure the process is still running in background
# No execution errors occurred. Make sure the background
# process with the recorded pid is still running.
status1 = self.endpoint1.node.status(self._pid1, self._ppid1)
status2 = self.endpoint2.node.status(self._pid2, self._ppid2)
if status1 == ProcStatus.FINISHED and \
status2 == ProcStatus.FINISHED:
# check if execution errors occurred
(out1, err1), proc1 = self.endpoint1.node.check_errors(
self.run_home(self.endpoint1))
(out2, err2), proc2 = self.endpoint2.node.check_errors(
self.run_home(self.endpoint2))
if err1 or err2:
msg = "Error occurred in tunnel"
self.error(msg, err1, err2)
self.fail()
else:
self.set_stopped()
self._last_state_check = tnow()
return self._state
def wait_local_port(self, endpoint):
""" Waits until the local_port file for the endpoint is generated,
and returns the port number
"""
return self.wait_file(endpoint, "local_port")
def wait_result(self, endpoint):
""" Waits until the return code file for the endpoint is generated
"""
return self.wait_file(endpoint, "ret_file")
def wait_file(self, endpoint, filename):
""" Waits until file on endpoint is generated """
result = None
delay = 1.0
for i in xrange(4):
(out, err), proc = endpoint.node.check_output(
self.run_home(endpoint), 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
def upload_remote_port(self, endpoint, port):
# upload remote port number to file
port = "%s\n" % port
endpoint.node.upload(port,
os.path.join(self.run_home(endpoint), "remote_port"),
text = True,
overwrite = False)
def valid_connection(self, guid):
# TODO: Validate!
return True