From 29c5a2335c73bc66c47ec8f2b41d64b9cdc1af1d Mon Sep 17 00:00:00 2001
From: "kjellander@webrtc.org"
<kjellander@webrtc.org@4adac7df-926f-26a2-2b94-8c16560cd09d>
Date: Fri, 1 Jun 2012 08:42:17 +0000
Subject: [PATCH] Renamed to Network Emulator and improved error handling.
Changed default start port of the port-range to 32768.
BUG=None
TEST=Tested locally.
Review URL: https://webrtc-codereview.appspot.com/627004
git-svn-id: http://webrtc.googlecode.com/svn/trunk@2338 4adac7df-926f-26a2-2b94-8c16560cd09d
---
.../config.py | 2 +-
.../emulate.py} | 62 ++++++++++---------
.../network_emulator.py} | 35 ++++++-----
3 files changed, 54 insertions(+), 45 deletions(-)
rename tools/{network_simulator => network_emulator}/config.py (96%)
rename tools/{network_simulator/simulate.py => network_emulator/emulate.py} (80%)
rename tools/{network_simulator/network_simulator.py => network_emulator/network_emulator.py} (83%)
diff --git a/tools/network_simulator/config.py b/tools/network_emulator/config.py
similarity index 96%
rename from tools/network_simulator/config.py
rename to tools/network_emulator/config.py
index ac450f6b9..60fa485db 100644
--- a/tools/network_simulator/config.py
+++ b/tools/network_emulator/config.py
@@ -7,7 +7,7 @@
# in the file PATENTS. All contributing project authors may
# be found in the AUTHORS file in the root of the source tree.
-"""Configuration class for network simulation."""
+"""Configuration class for network emulation."""
class ConnectionConfig(object):
diff --git a/tools/network_simulator/simulate.py b/tools/network_emulator/emulate.py
similarity index 80%
rename from tools/network_simulator/simulate.py
rename to tools/network_emulator/emulate.py
index b1b3e67a6..e25670574 100755
--- a/tools/network_simulator/simulate.py
+++ b/tools/network_emulator/emulate.py
@@ -16,12 +16,12 @@ import socket
import sys
import config
-import network_simulator
+import network_emulator
_DEFAULT_LOG_LEVEL = logging.INFO
# Default port range to apply network constraints on.
-_DEFAULT_PORT_RANGE = (30000, 65535)
+_DEFAULT_PORT_RANGE = (32768, 65535)
_PRESETS = [
config.ConnectionConfig(1, 'Generic, Bad', 95, 95, 250, 2, 100),
@@ -133,7 +133,7 @@ def _set_logger(verbose):
def _main():
- """Checks arguments, permissions and runs a network simulation."""
+ """Checks arguments, permissions and runs a network emulation."""
if os.name != 'posix':
print >> sys.stderr, 'This script is only supported on Linux and Mac.'
return 1
@@ -154,11 +154,11 @@ def _main():
if options.queue:
connection_config.queue_slots = options.queue
- simulator = network_simulator.NetworkSimulator(connection_config,
- options.port_range)
+ emulator = network_emulator.NetworkEmulator(connection_config,
+ options.port_range)
try:
- simulator.check_permissions()
- except network_simulator.NetworkSimulatorError as e:
+ emulator.check_permissions()
+ except network_emulator.NetworkEmulatorError as e:
logging.error('Error: %s\n\nCause: %s', e.msg, e.error)
return -1
@@ -167,28 +167,32 @@ def _main():
else:
external_ip = options.target_ip
- logging.info('Simulating traffic to/from IP: %s', external_ip)
- simulator.simulate(external_ip)
- logging.info('Started network simulation with the following configuration:\n'
- ' Receive bandwidth: %s kbps (%s kB/s)\n'
- ' Send bandwidth : %s kbps (%s kB/s)\n'
- ' Delay : %s ms\n'
- ' Packet loss : %s %%\n'
- ' Queue slots : %s',
- connection_config.receive_bw_kbps,
- connection_config.receive_bw_kbps/8,
- connection_config.send_bw_kbps,
- connection_config.send_bw_kbps/8,
- connection_config.delay_ms,
- connection_config.packet_loss_percent,
- connection_config.queue_slots)
- logging.info('Affected traffic: IP traffic on ports %s-%s',
- options.port_range[0], options.port_range[1])
- raw_input('Press Enter to abort Network simulation...')
- logging.info('Flushing all Dummynet rules...')
- simulator.cleanup()
- logging.info('Completed Network Simulation.')
- return 0
+ logging.info('Constraining traffic to/from IP: %s', external_ip)
+ try:
+ emulator.emulate(external_ip)
+ logging.info('Started network emulation with the following configuration:\n'
+ ' Receive bandwidth: %s kbps (%s kB/s)\n'
+ ' Send bandwidth : %s kbps (%s kB/s)\n'
+ ' Delay : %s ms\n'
+ ' Packet loss : %s %%\n'
+ ' Queue slots : %s',
+ connection_config.receive_bw_kbps,
+ connection_config.receive_bw_kbps/8,
+ connection_config.send_bw_kbps,
+ connection_config.send_bw_kbps/8,
+ connection_config.delay_ms,
+ connection_config.packet_loss_percent,
+ connection_config.queue_slots)
+ logging.info('Affected traffic: IP traffic on ports %s-%s',
+ options.port_range[0], options.port_range[1])
+ raw_input('Press Enter to abort Network Emulation...')
+ logging.info('Flushing all Dummynet rules...')
+ emulator.cleanup()
+ logging.info('Completed Network Emulation.')
+ return 0
+ except network_emulator.NetworkEmulatorError as e:
+ logging.error('Error: %s\n\nCause: %s', e.msg, e.error)
+ return -2
if __name__ == '__main__':
sys.exit(_main())
diff --git a/tools/network_simulator/network_simulator.py b/tools/network_emulator/network_emulator.py
similarity index 83%
rename from tools/network_simulator/network_simulator.py
rename to tools/network_emulator/network_emulator.py
index 3518999c2..2876939ea 100644
--- a/tools/network_simulator/network_simulator.py
+++ b/tools/network_emulator/network_emulator.py
@@ -12,10 +12,11 @@
import logging
import os
import subprocess
+import sys
-class NetworkSimulatorError(BaseException):
- """Exception raised for errors in the network simulator.
+class NetworkEmulatorError(BaseException):
+ """Exception raised for errors in the network emulator.
Attributes:
msg: User defined error message.
@@ -35,15 +36,15 @@ class NetworkSimulatorError(BaseException):
self.error = error
-class NetworkSimulator(object):
- """A network simulator that can constrain the network using Dummynet."""
+class NetworkEmulator(object):
+ """A network emulator that can constrain the network using Dummynet."""
def __init__(self, connection_config, port_range):
"""Constructor.
Args:
connection_config: A config.ConnectionConfig object containing the
- characteristics for the connection to be simulated.
+ characteristics for the connection to be emulation.
port_range: Tuple containing two integers defining the port range.
"""
self._pipe_counter = 0
@@ -51,8 +52,8 @@ class NetworkSimulator(object):
self._port_range = port_range
self._connection_config = connection_config
- def simulate(self, target_ip):
- """Starts a network simulation by setting up Dummynet rules.
+ def emulate(self, target_ip):
+ """Starts a network emulation by setting up Dummynet rules.
Args:
target_ip: The IP address of the interface that shall be that have the
@@ -71,7 +72,7 @@ class NetworkSimulator(object):
self._connection_config.queue_slots)
logging.debug('Created send pipe: %s', send_pipe_id)
- # Adding the rules will start the simulation.
+ # Adding the rules will start the emulation.
incoming_rule_id = self._create_dummynet_rule(receive_pipe_id, 'any',
target_ip, self._port_range)
logging.debug('Created incoming rule: %s', incoming_rule_id)
@@ -83,7 +84,7 @@ class NetworkSimulator(object):
"""Checks if permissions are available to run Dummynet commands.
Raises:
- NetworkSimulatorError: If permissions to run Dummynet commands are not
+ NetworkEmulatorError: If permissions to run Dummynet commands are not
available.
"""
if os.geteuid() != 0:
@@ -93,17 +94,17 @@ class NetworkSimulator(object):
'root or have password-less sudo access to this command.'))
def cleanup(self):
- """Stops the network simulation by flushing all Dummynet rules.
+ """Stops the network emulation by flushing all Dummynet rules.
Notice that this will flush any rules that may have been created previously
- before starting the simulation.
+ before starting the emulation.
"""
self._run_shell_command(['sudo', 'ipfw', '-f', 'flush'],
'Failed to flush Dummynet rules!')
def _create_dummynet_rule(self, pipe_id, from_address, to_address,
port_range):
- """Creates a network simulation rule and returns its ID.
+ """Creates a network emulation rule and returns its ID.
Args:
pipe_id: integer ID of the pipe.
@@ -144,7 +145,11 @@ class NetworkSimulator(object):
'delay', '%sms' % delay_ms,
'plr', (packet_loss_percent/100.0),
'queue', queue_slots]
- self._run_shell_command(cmd, 'Failed to create Dummynet pipe')
+ error_message = 'Failed to create Dummynet pipe. '
+ if sys.platform.startswith('linux'):
+ error_message += ('Make sure you have loaded the ipfw_mod.ko module to '
+ 'your kernel (sudo insmod /path/to/ipfw_mod.ko)')
+ self._run_shell_command(cmd, error_message)
return self._pipe_counter
def _run_shell_command(self, command, msg=None):
@@ -158,7 +163,7 @@ class NetworkSimulator(object):
The standard output from running the command.
Raises:
- NetworkSimulatorError: If command fails. Message is set by the msg
+ NetworkEmulatorError: If command fails. Message is set by the msg
parameter.
"""
cmd_list = [str(x) for x in command]
@@ -169,5 +174,5 @@ class NetworkSimulator(object):
stderr=subprocess.PIPE)
output, error = process.communicate()
if process.returncode != 0:
- raise NetworkSimulatorError(msg, cmd, process.returncode, output, error)
+ raise NetworkEmulatorError(msg, cmd, process.returncode, output, error)
return output.strip()