lab/mininet
1
0
Fork 0
Code Issues Pull Requests Actions 2 Packages Projects Releases Wiki Activity

Merge pull request #353 from mininet/devel/nat

Browse Source 
Adding NAT class to NodeLib
This commit is contained in:
lantz
2014-08-21 14:16:41 -05:00
parent a3e1a9a44d 7c4e5b14cb
commit 16a384ab4b
6 changed files with 219 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files
bin/mn
+7
View File
@@ -200,6 +200,9 @@ class MininetRunner( object ):
opts.add_option( '--pin', action='store_true',
default=False, help="pin hosts to CPU cores "
"(requires --host cfs or --host rt)" )
opts.add_option( '--nat', action='store_true',
default=False, help="adds a NAT to the topology "
"that connects Mininet to the physical network" )
opts.add_option( '--version', action='callback', callback=version )
self.options, self.args = opts.parse_args()
@@ -257,6 +260,10 @@ class MininetRunner( object ):
autoStaticArp=arp, autoPinCpus=pin,
listenPort=listenPort )
if self.options.nat:
nat = mn.addNAT()
nat.configDefault()
if self.options.pre:
CLI( mn, script=self.options.pre )
examples/natnet.py
Executable
+70
View File
@@ -0,0 +1,70 @@
#!/usr/bin/python
"""
natnet.py: Example network with NATs
h0
|
s0
|
----------------
| |
nat1 nat2
| |
s1 s2
| |
h1 h2
"""
from mininet.topo import Topo
from mininet.net import Mininet
from mininet.nodelib import NAT
from mininet.log import setLogLevel
from mininet.cli import CLI
from mininet.util import irange
class InternetTopo(Topo):
"Single switch connected to n hosts."
def __init__(self, n=2, h=1, **opts):
Topo.__init__(self, **opts)
# set up inet switch
inetSwitch = self.addSwitch('s0')
# add inet host
inetHost = self.addHost('h0')
self.addLink(inetSwitch, inetHost)
# add local nets
for i in irange(1, n):
inetIntf = 'nat%d-eth0' % i
localIntf = 'nat%d-eth1' % i
localIP = '192.168.%d.1' % i
localSubnet = '192.168.%d.0/24' % i
natParams = { 'ip' : '%s/24' % localIP }
# add NAT to topology
nat = self.addNode('nat%d' % i, cls=NAT, subnet=localSubnet,
inetIntf=inetIntf, localIntf=localIntf)
switch = self.addSwitch('s%d' % i)
# connect NAT to inet and local switches
self.addLink(nat, inetSwitch, intfName1=inetIntf)
self.addLink(nat, switch, intfName1=localIntf, params1=natParams)
# add host and connect to local switch
host = self.addHost('h%d' % i,
ip='192.168.%d.100/24' % i,
defaultRoute='via %s' % localIP)
self.addLink(host, switch)
def run():
"Create network and run the CLI"
topo = InternetTopo()
net = Mininet(topo=topo)
net.start()
CLI(net)
net.stop()
if __name__ == '__main__':
setLogLevel('info')
run()
examples/test/test_natnet.py
+57
View File
@@ -0,0 +1,57 @@
#!/usr/bin/env python
"""
Test for natnet.py
"""
import unittest
import pexpect
from mininet.util import quietRun
class testNATNet( unittest.TestCase ):
prompt = 'mininet>'
def setUp( self ):
self.net = pexpect.spawn( 'python -m mininet.examples.natnet' )
self.net.expect( self.prompt )
def testPublicPing( self ):
"Attempt to ping the public server (h0) from h1 and h2"
self.net.sendline( 'h1 ping -c 1 h0' )
self.net.expect ( '(\d+)% packet loss' )
percent = int( self.net.match.group( 1 ) ) if self.net.match else -1
self.assertEqual( percent, 0 )
self.net.expect( self.prompt )
self.net.sendline( 'h2 ping -c 1 h0' )
self.net.expect ( '(\d+)% packet loss' )
percent = int( self.net.match.group( 1 ) ) if self.net.match else -1
self.assertEqual( percent, 0 )
self.net.expect( self.prompt )
def testPrivatePing( self ):
"Attempt to ping h1 and h2 from public server"
self.net.sendline( 'h0 ping -c 1 -t 1 h1' )
result = self.net.expect ( [ 'unreachable', 'loss' ] )
self.assertEqual( result, 0 )
self.net.expect( self.prompt )
self.net.sendline( 'h0 ping -c 1 -t 1 h2' )
result = self.net.expect ( [ 'unreachable', 'loss' ] )
self.assertEqual( result, 0 )
self.net.expect( self.prompt )
def testPrivateToPrivatePing( self ):
"Attempt to ping from NAT'ed host h1 to NAT'ed host h2"
self.net.sendline( 'h1 ping -c 1 -t 1 h2' )
result = self.net.expect ( [ '[Uu]nreachable', 'loss' ] )
self.assertEqual( result, 0 )
self.net.expect( self.prompt )
def tearDown( self ):
self.net.sendline( 'exit' )
self.net.wait()
if __name__ == '__main__':
unittest.main()
mininet/net.py
+16 -1
View File
@@ -97,6 +97,7 @@ from itertools import chain, groupby
from mininet.cli import CLI
from mininet.log import info, error, debug, output, warn
from mininet.node import Host, OVSKernelSwitch, DefaultController, Controller
from mininet.nodelib import NAT
from mininet.link import Link, Intf
from mininet.util import quietRun, fixLimits, numCores, ensureRoot
from mininet.util import macColonHex, ipStr, ipParse, netParse, ipAdd
@@ -208,7 +209,7 @@ class Mininet( object ):
prefixLen=self.prefixLen ) +
'/%s' % self.prefixLen }
if self.autoSetMacs:
defaults[ 'mac'] = macColonHex( self.nextIP )
defaults[ 'mac' ] = macColonHex( self.nextIP )
if self.autoPinCpus:
defaults[ 'cores' ] = self.nextCore
self.nextCore = ( self.nextCore + 1 ) % self.numCores
@@ -260,6 +261,20 @@ class Mininet( object ):
self.nameToNode[ name ] = controller_new
return controller_new
def addNAT( self, name='nat0', connect=True, inNamespace=False, **params ):
nat = self.addHost( name, cls=NAT, inNamespace=inNamespace,
subnet=self.ipBase, **params )
# find first switch and create link
if connect:
# connect the nat to the first switch
self.addLink( nat, self.switches[ 0 ] )
# set the default route on hosts
natIP = nat.params[ 'ip' ].split('/')[ 0 ]
for host in self.hosts:
if host.inNamespace:
host.setDefaultRoute( 'via %s' % natIP )
return nat
# BL: We now have four ways to look up nodes
# This may (should?) be cleaned up in the future.
def getNodeByName( self, *args ):
mininet/node.py
-1
View File
@@ -1358,7 +1358,6 @@ class RemoteController( Controller ):
warn( "Unable to contact the remote controller"
" at %s:%d\n" % ( self.ip, self.port ) )
def DefaultController( name, order=[ Controller, OVSController ], **kwargs ):
"find any controller that is available and run it"
for controller in order:
mininet/nodelib.py
+69 -5
View File
@@ -1,15 +1,12 @@
"""
Node Library for Mininet
This contains additional Node types which you may find to be useful
This contains additional Node types which you may find to be useful.
"""
from mininet.net import Mininet
from mininet.topo import Topo
from mininet.node import Switch
from mininet.node import Node, Switch
from mininet.log import setLogLevel, info
class LinuxBridge( Switch ):
"Linux Bridge (with optional spanning tree)"
@@ -49,3 +46,70 @@ class LinuxBridge( Switch ):
self.cmd( 'ifconfig', self, 'down' )
self.cmd( 'brctl delbr', self )
class NAT( Node ):
"""NAT: Provides connectivity to external network"""
def __init__( self, name, inetIntf='eth0', subnet='10.0/8', localIntf=None, **params):
super( NAT, self ).__init__( name, **params )
"""Start NAT/forwarding between Mininet and external network
inetIntf: interface for internet access
subnet: Mininet subnet (default 10.0/8)="""
self.inetIntf = inetIntf
self.subnet = subnet
self.localIntf = localIntf
def config( self, **params ):
super( NAT, self).config( **params )
"""Configure the NAT and iptables"""
if not self.localIntf:
self.localIntf = self.defaultIntf()
self.cmd( 'sysctl net.ipv4.ip_forward=0' )
# Flush any currently active rules
# TODO: is this safe?
self.cmd( 'iptables -F' )
self.cmd( 'iptables -t nat -F' )
# Create default entries for unmatched traffic
self.cmd( 'iptables -P INPUT ACCEPT' )
self.cmd( 'iptables -P OUTPUT ACCEPT' )
self.cmd( 'iptables -P FORWARD DROP' )
# Configure NAT
self.cmd( 'iptables -I FORWARD -i', self.localIntf, '-d', self.subnet, '-j DROP' )
self.cmd( 'iptables -A FORWARD -i', self.localIntf, '-s', self.subnet, '-j ACCEPT' )
self.cmd( 'iptables -A FORWARD -i', self.inetIntf, '-d', self.subnet, '-j ACCEPT' )
self.cmd( 'iptables -t nat -A POSTROUTING -o ', self.inetIntf, '-j MASQUERADE' )
# Instruct the kernel to perform forwarding
self.cmd( 'sysctl net.ipv4.ip_forward=1' )
# Prevent network-manager from messing with our interface
# by specifying manual configuration in /etc/network/interfaces
intf = self.localIntf
cfile = '/etc/network/interfaces'
line = '\niface %s inet manual\n' % intf
config = open( cfile ).read()
if ( line ) not in config:
info( '*** Adding "' + line.strip() + '" to ' + cfile )
with open( cfile, 'a' ) as f:
f.write( line )
# Probably need to restart network-manager to be safe -
# hopefully this won't disconnect you
self.cmd( 'service network-manager restart' )
def terminate( self ):
"""Stop NAT/forwarding between Mininet and external network"""
# Flush any currently active rules
# TODO: is this safe?
self.cmd( 'iptables -F' )
self.cmd( 'iptables -t nat -F' )
# Instruct the kernel to stop forwarding
self.cmd( 'sysctl net.ipv4.ip_forward=0' )
super( NAT, self ).terminate()