Statistics
| Branch: | Tag: | Revision:

mininet / mininet / node.py @ e16c5fe9

History | View | Annotate | Download (52.2 KB)

1
"""
2
Node objects for Mininet.
3

4
Nodes provide a simple abstraction for interacting with hosts, switches
5
and controllers. Local nodes are simply one or more processes on the local
6
machine.
7

8
Node: superclass for all (primarily local) network nodes.
9

10
Host: a virtual host. By default, a host is simply a shell; commands
11
    may be sent using Cmd (which waits for output), or using sendCmd(),
12
    which returns immediately, allowing subsequent monitoring using
13
    monitor(). Examples of how to run experiments using this
14
    functionality are provided in the examples/ directory.
15

16
CPULimitedHost: a virtual host whose CPU bandwidth is limited by
17
    RT or CFS bandwidth limiting.
18

19
HostWithPrivateDirs: a virtual host that has user-specified private
20
    directories. These may be temporary directories stored as a tmpfs,
21
    or persistent directories that are mounted from another directory in
22
    the root filesystem.
23

24
Switch: superclass for switch nodes.
25

26
UserSwitch: a switch using the user-space switch from the OpenFlow
27
    reference implementation.
28

29
KernelSwitch: a switch using the kernel switch from the OpenFlow reference
30
    implementation.
31

32
OVSSwitch: a switch using the OpenVSwitch OpenFlow-compatible switch
33
    implementation (openvswitch.org).
34

35
Controller: superclass for OpenFlow controllers. The default controller
36
    is controller(8) from the reference implementation.
37

38
NOXController: a controller node using NOX (noxrepo.org).
39

40
RemoteController: a remote controller node, which may use any
41
    arbitrary OpenFlow-compatible controller, and which is not
42
    created or managed by mininet.
43

44
Future enhancements:
45

46
- Possibly make Node, Switch and Controller more abstract so that
47
  they can be used for both local and remote nodes
48

49
- Create proxy objects for remote nodes (Mininet: Cluster Edition)
50
"""
51

    
52
import os
53
import pty
54
import re
55
import signal
56
import select
57
from subprocess import Popen, PIPE, STDOUT
58
from operator import or_
59
from time import sleep
60

    
61
from mininet.log import info, error, warn, debug
62
from mininet.util import ( quietRun, errRun, errFail, moveIntf, isShellBuiltin,
63
                           numCores, retry, mountCgroups )
64
from mininet.moduledeps import moduleDeps, pathCheck, OVS_KMOD, OF_KMOD, TUN
65
from mininet.link import Link, Intf, TCIntf
66
from re import findall
67
from distutils.version import StrictVersion
68

    
69
class Node( object ):
70
    """A virtual network node is simply a shell in a network namespace.
71
       We communicate with it using pipes."""
72

    
73
    portBase = 0  # Nodes always start with eth0/port0, even in OF 1.0
74

    
75
    def __init__( self, name, inNamespace=True, **params ):
76
        """name: name of node
77
           inNamespace: in network namespace?
78
           params: Node parameters (see config() for details)"""
79

    
80
        # Make sure class actually works
81
        self.checkSetup()
82

    
83
        self.name = params.get( 'name', name )
84
        self.inNamespace = params.get( 'inNamespace', inNamespace )
85

    
86
        # Stash configuration parameters for future reference
87
        self.params = params
88

    
89
        self.intfs = {}  # dict of port numbers to interfaces
90
        self.ports = {}  # dict of interfaces to port numbers
91
                         # replace with Port objects, eventually ?
92
        self.nameToIntf = {}  # dict of interface names to Intfs
93

    
94
        # Make pylint happy
95
        ( self.shell, self.execed, self.pid, self.stdin, self.stdout,
96
            self.lastPid, self.lastCmd, self.pollOut ) = (
97
                None, None, None, None, None, None, None, None )
98
        self.waiting = False
99
        self.readbuf = ''
100

    
101
        # Start command interpreter shell
102
        self.startShell()
103

    
104
    # File descriptor to node mapping support
105
    # Class variables and methods
106

    
107
    inToNode = {}  # mapping of input fds to nodes
108
    outToNode = {}  # mapping of output fds to nodes
109

    
110
    @classmethod
111
    def fdToNode( cls, fd ):
112
        """Return node corresponding to given file descriptor.
113
           fd: file descriptor
114
           returns: node"""
115
        node = cls.outToNode.get( fd )
116
        return node or cls.inToNode.get( fd )
117

    
118
    # Command support via shell process in namespace
119
    def startShell( self, mnopts=None ):
120
        "Start a shell process for running commands"
121
        if self.shell:
122
            error( "%s: shell is already running\n" % self.name )
123
            return
124
        # mnexec: (c)lose descriptors, (d)etach from tty,
125
        # (p)rint pid, and run in (n)amespace
126
        opts = '-cd' if mnopts is None else mnopts
127
        if self.inNamespace:
128
            opts += 'n'
129
        # bash -m: enable job control, i: force interactive
130
        # -s: pass $* to shell, and make process easy to find in ps
131
        # prompt is set to sentinel chr( 127 )
132
        cmd = [ 'mnexec', opts, 'env',  'PS1=' + chr( 127 ),
133
                'bash', '--norc', '-mis', 'mininet:' + self.name ]
134
        # Spawn a shell subprocess in a pseudo-tty, to disable buffering
135
        # in the subprocess and insulate it from signals (e.g. SIGINT)
136
        # received by the parent
137
        master, slave = pty.openpty()
138
        self.shell = self._popen( cmd, stdin=slave, stdout=slave, stderr=slave,
139
                                  close_fds=False )
140
        self.stdin = os.fdopen( master, 'rw' )
141
        self.stdout = self.stdin
142
        self.pid = self.shell.pid
143
        self.pollOut = select.poll()
144
        self.pollOut.register( self.stdout )
145
        # Maintain mapping between file descriptors and nodes
146
        # This is useful for monitoring multiple nodes
147
        # using select.poll()
148
        self.outToNode[ self.stdout.fileno() ] = self
149
        self.inToNode[ self.stdin.fileno() ] = self
150
        self.execed = False
151
        self.lastCmd = None
152
        self.lastPid = None
153
        self.readbuf = ''
154
        # Wait for prompt
155
        while True:
156
            data = self.read( 1024 )
157
            if data[ -1 ] == chr( 127 ):
158
                break
159
            self.pollOut.poll()
160
        self.waiting = False
161
        self.cmd( 'stty -echo' )
162
        self.cmd( 'set +m' )
163

    
164
    def _popen( self, cmd, **params ):
165
        """Internal method: spawn and return a process
166
            cmd: command to run (list)
167
            params: parameters to Popen()"""
168
        return Popen( cmd, **params )
169

    
170
    def cleanup( self ):
171
        "Help python collect its garbage."
172
        # Intfs may end up in root NS
173
        for intfName in self.intfNames():
174
            if self.name in intfName:
175
                quietRun( 'ip link del ' + intfName )
176
        self.shell = None
177

    
178
    # Subshell I/O, commands and control
179

    
180
    def read( self, maxbytes=1024 ):
181
        """Buffered read from node, non-blocking.
182
           maxbytes: maximum number of bytes to return"""
183
        count = len( self.readbuf )
184
        if count < maxbytes:
185
            data = os.read( self.stdout.fileno(), maxbytes - count )
186
            self.readbuf += data
187
        if maxbytes >= len( self.readbuf ):
188
            result = self.readbuf
189
            self.readbuf = ''
190
        else:
191
            result = self.readbuf[ :maxbytes ]
192
            self.readbuf = self.readbuf[ maxbytes: ]
193
        return result
194

    
195
    def readline( self ):
196
        """Buffered readline from node, non-blocking.
197
           returns: line (minus newline) or None"""
198
        self.readbuf += self.read( 1024 )
199
        if '\n' not in self.readbuf:
200
            return None
201
        pos = self.readbuf.find( '\n' )
202
        line = self.readbuf[ 0: pos ]
203
        self.readbuf = self.readbuf[ pos + 1: ]
204
        return line
205

    
206
    def write( self, data ):
207
        """Write data to node.
208
           data: string"""
209
        os.write( self.stdin.fileno(), data )
210

    
211
    def terminate( self ):
212
        "Send kill signal to Node and clean up after it."
213
        if self.shell:
214
            if self.shell.poll() is None:
215
                os.killpg( self.shell.pid, signal.SIGHUP )
216
        self.cleanup()
217

    
218
    def stop( self ):
219
        "Stop node."
220
        self.terminate()
221

    
222
    def waitReadable( self, timeoutms=None ):
223
        """Wait until node's output is readable.
224
           timeoutms: timeout in ms or None to wait indefinitely."""
225
        if len( self.readbuf ) == 0:
226
            self.pollOut.poll( timeoutms )
227

    
228
    def sendCmd( self, *args, **kwargs ):
229
        """Send a command, followed by a command to echo a sentinel,
230
           and return without waiting for the command to complete.
231
           args: command and arguments, or string
232
           printPid: print command's PID?"""
233
        assert not self.waiting
234
        printPid = kwargs.get( 'printPid', True )
235
        # Allow sendCmd( [ list ] )
236
        if len( args ) == 1 and type( args[ 0 ] ) is list:
237
            cmd = args[ 0 ]
238
        # Allow sendCmd( cmd, arg1, arg2... )
239
        elif len( args ) > 0:
240
            cmd = args
241
        # Convert to string
242
        if not isinstance( cmd, str ):
243
            cmd = ' '.join( [ str( c ) for c in cmd ] )
244
        if not re.search( r'\w', cmd ):
245
            # Replace empty commands with something harmless
246
            cmd = 'echo -n'
247
        self.lastCmd = cmd
248
        # if a builtin command is backgrounded, it still yields a PID
249
        if len( cmd ) > 0 and cmd[ -1 ] == '&':
250
            # print ^A{pid}\n so monitor() can set lastPid
251
            cmd += ' printf "\\001%d\\012" $! '
252
        elif printPid and not isShellBuiltin( cmd ):
253
            cmd = 'mnexec -p ' + cmd
254
        self.write( cmd + '\n' )
255
        self.lastPid = None
256
        self.waiting = True
257

    
258
    def sendInt( self, intr=chr( 3 ) ):
259
        "Interrupt running command."
260
        debug( 'sendInt: writing chr(%d)\n' % ord( intr ) )
261
        self.write( intr )
262

    
263
    def monitor( self, timeoutms=None, findPid=True ):
264
        """Monitor and return the output of a command.
265
           Set self.waiting to False if command has completed.
266
           timeoutms: timeout in ms or None to wait indefinitely
267
           findPid: look for PID from mnexec -p"""
268
        self.waitReadable( timeoutms )
269
        data = self.read( 1024 )
270
        pidre = r'\[\d+\] \d+\r\n'
271
        # Look for PID
272
        marker = chr( 1 ) + r'\d+\r\n'
273
        if findPid and chr( 1 ) in data:
274
            # suppress the job and PID of a backgrounded command
275
            if re.findall( pidre, data ):
276
                data = re.sub( pidre, '', data )
277
            # Marker can be read in chunks; continue until all of it is read
278
            while not re.findall( marker, data ):
279
                data += self.read( 1024 )
280
            markers = re.findall( marker, data )
281
            if markers:
282
                self.lastPid = int( markers[ 0 ][ 1: ] )
283
                data = re.sub( marker, '', data )
284
        # Look for sentinel/EOF
285
        if len( data ) > 0 and data[ -1 ] == chr( 127 ):
286
            self.waiting = False
287
            data = data[ :-1 ]
288
        elif chr( 127 ) in data:
289
            self.waiting = False
290
            data = data.replace( chr( 127 ), '' )
291
        return data
292

    
293
    def waitOutput( self, verbose=False, findPid=True ):
294
        """Wait for a command to complete.
295
           Completion is signaled by a sentinel character, ASCII(127)
296
           appearing in the output stream.  Wait for the sentinel and return
297
           the output, including trailing newline.
298
           verbose: print output interactively"""
299
        log = info if verbose else debug
300
        output = ''
301
        while self.waiting:
302
            data = self.monitor()
303
            output += data
304
            log( data )
305
        return output
306

    
307
    def cmd( self, *args, **kwargs ):
308
        """Send a command, wait for output, and return it.
309
           cmd: string"""
310
        verbose = kwargs.get( 'verbose', False )
311
        log = info if verbose else debug
312
        log( '*** %s : %s\n' % ( self.name, args ) )
313
        self.sendCmd( *args, **kwargs )
314
        return self.waitOutput( verbose )
315

    
316
    def cmdPrint( self, *args):
317
        """Call cmd and printing its output
318
           cmd: string"""
319
        return self.cmd( *args, **{ 'verbose': True } )
320

    
321
    def popen( self, *args, **kwargs ):
322
        """Return a Popen() object in our namespace
323
           args: Popen() args, single list, or string
324
           kwargs: Popen() keyword args"""
325
        defaults = { 'stdout': PIPE, 'stderr': PIPE,
326
                     'mncmd':
327
                     [ 'mnexec', '-da', str( self.pid ) ] }
328
        defaults.update( kwargs )
329
        if len( args ) == 1:
330
            if type( args[ 0 ] ) is list:
331
                # popen([cmd, arg1, arg2...])
332
                cmd = args[ 0 ]
333
            elif type( args[ 0 ] ) is str:
334
                # popen("cmd arg1 arg2...")
335
                cmd = args[ 0 ].split()
336
            else:
337
                raise Exception( 'popen() requires a string or list' )
338
        elif len( args ) > 0:
339
            # popen( cmd, arg1, arg2... )
340
            cmd = list( args )
341
        # Attach to our namespace  using mnexec -a
342
        cmd = defaults.pop( 'mncmd' ) + cmd
343
        # Shell requires a string, not a list!
344
        if defaults.get( 'shell', False ):
345
            cmd = ' '.join( cmd )
346
        popen = self._popen( cmd, **defaults )
347
        return popen
348

    
349
    def pexec( self, *args, **kwargs ):
350
        """Execute a command using popen
351
           returns: out, err, exitcode"""
352
        popen = self.popen( *args, stdin=PIPE, stdout=PIPE, stderr=PIPE,
353
                           **kwargs )
354
        # Warning: this can fail with large numbers of fds!
355
        out, err = popen.communicate()
356
        exitcode = popen.wait()
357
        return out, err, exitcode
358

    
359
    # Interface management, configuration, and routing
360

    
361
    # BL notes: This might be a bit redundant or over-complicated.
362
    # However, it does allow a bit of specialization, including
363
    # changing the canonical interface names. It's also tricky since
364
    # the real interfaces are created as veth pairs, so we can't
365
    # make a single interface at a time.
366

    
367
    def newPort( self ):
368
        "Return the next port number to allocate."
369
        if len( self.ports ) > 0:
370
            return max( self.ports.values() ) + 1
371
        return self.portBase
372

    
373
    def addIntf( self, intf, port=None, moveIntfFn=moveIntf ):
374
        """Add an interface.
375
           intf: interface
376
           port: port number (optional, typically OpenFlow port number)
377
           moveIntfFn: function to move interface (optional)"""
378
        if port is None:
379
            port = self.newPort()
380
        self.intfs[ port ] = intf
381
        self.ports[ intf ] = port
382
        self.nameToIntf[ intf.name ] = intf
383
        debug( '\n' )
384
        debug( 'added intf %s (%d) to node %s\n' % (
385
                intf, port, self.name ) )
386
        if self.inNamespace:
387
            debug( 'moving', intf, 'into namespace for', self.name, '\n' )
388
            moveIntfFn( intf.name, self  )
389

    
390
    def defaultIntf( self ):
391
        "Return interface for lowest port"
392
        ports = self.intfs.keys()
393
        if ports:
394
            return self.intfs[ min( ports ) ]
395
        else:
396
            warn( '*** defaultIntf: warning:', self.name,
397
                  'has no interfaces\n' )
398

    
399
    def intf( self, intf='' ):
400
        """Return our interface object with given string name,
401
           default intf if name is falsy (None, empty string, etc).
402
           or the input intf arg.
403

404
        Having this fcn return its arg for Intf objects makes it
405
        easier to construct functions with flexible input args for
406
        interfaces (those that accept both string names and Intf objects).
407
        """
408
        if not intf:
409
            return self.defaultIntf()
410
        elif type( intf ) is str:
411
            return self.nameToIntf[ intf ]
412
        else:
413
            return intf
414

    
415
    def connectionsTo( self, node):
416
        "Return [ intf1, intf2... ] for all intfs that connect self to node."
417
        # We could optimize this if it is important
418
        connections = []
419
        for intf in self.intfList():
420
            link = intf.link
421
            if link:
422
                node1, node2 = link.intf1.node, link.intf2.node
423
                if node1 == self and node2 == node:
424
                    connections += [ ( intf, link.intf2 ) ]
425
                elif node1 == node and node2 == self:
426
                    connections += [ ( intf, link.intf1 ) ]
427
        return connections
428

    
429
    def deleteIntfs( self, checkName=True ):
430
        """Delete all of our interfaces.
431
           checkName: only delete interfaces that contain our name"""
432
        # In theory the interfaces should go away after we shut down.
433
        # However, this takes time, so we're better off removing them
434
        # explicitly so that we won't get errors if we run before they
435
        # have been removed by the kernel. Unfortunately this is very slow,
436
        # at least with Linux kernels before 2.6.33
437
        for intf in self.intfs.values():
438
            # Protect against deleting hardware interfaces
439
            if ( self.name in intf.name ) or ( not checkName ):
440
                intf.delete()
441
                info( '.' )
442

    
443
    # Routing support
444

    
445
    def setARP( self, ip, mac ):
446
        """Add an ARP entry.
447
           ip: IP address as string
448
           mac: MAC address as string"""
449
        result = self.cmd( 'arp', '-s', ip, mac )
450
        return result
451

    
452
    def setHostRoute( self, ip, intf ):
453
        """Add route to host.
454
           ip: IP address as dotted decimal
455
           intf: string, interface name"""
456
        return self.cmd( 'route add -host', ip, 'dev', intf )
457

    
458
    def setDefaultRoute( self, intf=None ):
459
        """Set the default route to go through intf.
460
           intf: Intf or {dev <intfname> via <gw-ip> ...}"""
461
        # Note setParam won't call us if intf is none
462
        if type( intf ) is str and ' ' in intf:
463
            params = intf
464
        else:
465
            params = 'dev %s' % intf
466
        self.cmd( 'ip route del default' )
467
        return self.cmd( 'ip route add default', params )
468

    
469
    # Convenience and configuration methods
470

    
471
    def setMAC( self, mac, intf=None ):
472
        """Set the MAC address for an interface.
473
           intf: intf or intf name
474
           mac: MAC address as string"""
475
        return self.intf( intf ).setMAC( mac )
476

    
477
    def setIP( self, ip, prefixLen=8, intf=None ):
478
        """Set the IP address for an interface.
479
           intf: intf or intf name
480
           ip: IP address as a string
481
           prefixLen: prefix length, e.g. 8 for /8 or 16M addrs"""
482
        # This should probably be rethought
483
        if '/' not in ip:
484
            ip = '%s/%s' % ( ip, prefixLen )
485
        return self.intf( intf ).setIP( ip )
486

    
487
    def IP( self, intf=None ):
488
        "Return IP address of a node or specific interface."
489
        return self.intf( intf ).IP()
490

    
491
    def MAC( self, intf=None ):
492
        "Return MAC address of a node or specific interface."
493
        return self.intf( intf ).MAC()
494

    
495
    def intfIsUp( self, intf=None ):
496
        "Check if an interface is up."
497
        return self.intf( intf ).isUp()
498

    
499
    # The reason why we configure things in this way is so
500
    # That the parameters can be listed and documented in
501
    # the config method.
502
    # Dealing with subclasses and superclasses is slightly
503
    # annoying, but at least the information is there!
504

    
505
    def setParam( self, results, method, **param ):
506
        """Internal method: configure a *single* parameter
507
           results: dict of results to update
508
           method: config method name
509
           param: arg=value (ignore if value=None)
510
           value may also be list or dict"""
511
        name, value = param.items()[ 0 ]
512
        f = getattr( self, method, None )
513
        if not f or value is None:
514
            return
515
        if type( value ) is list:
516
            result = f( *value )
517
        elif type( value ) is dict:
518
            result = f( **value )
519
        else:
520
            result = f( value )
521
        results[ name ] = result
522
        return result
523

    
524
    def config( self, mac=None, ip=None,
525
                defaultRoute=None, lo='up', **_params ):
526
        """Configure Node according to (optional) parameters:
527
           mac: MAC address for default interface
528
           ip: IP address for default interface
529
           ifconfig: arbitrary interface configuration
530
           Subclasses should override this method and call
531
           the parent class's config(**params)"""
532
        # If we were overriding this method, we would call
533
        # the superclass config method here as follows:
534
        # r = Parent.config( **_params )
535
        r = {}
536
        self.setParam( r, 'setMAC', mac=mac )
537
        self.setParam( r, 'setIP', ip=ip )
538
        self.setParam( r, 'setDefaultRoute', defaultRoute=defaultRoute )
539
        # This should be examined
540
        self.cmd( 'ifconfig lo ' + lo )
541
        return r
542

    
543
    def configDefault( self, **moreParams ):
544
        "Configure with default parameters"
545
        self.params.update( moreParams )
546
        self.config( **self.params )
547

    
548
    # This is here for backward compatibility
549
    def linkTo( self, node, link=Link ):
550
        """(Deprecated) Link to another node
551
           replace with Link( node1, node2)"""
552
        return link( self, node )
553

    
554
    # Other methods
555

    
556
    def intfList( self ):
557
        "List of our interfaces sorted by port number"
558
        return [ self.intfs[ p ] for p in sorted( self.intfs.iterkeys() ) ]
559

    
560
    def intfNames( self ):
561
        "The names of our interfaces sorted by port number"
562
        return [ str( i ) for i in self.intfList() ]
563

    
564
    def __repr__( self ):
565
        "More informative string representation"
566
        intfs = ( ','.join( [ '%s:%s' % ( i.name, i.IP() )
567
                              for i in self.intfList() ] ) )
568
        return '<%s %s: %s pid=%s> ' % (
569
            self.__class__.__name__, self.name, intfs, self.pid )
570

    
571
    def __str__( self ):
572
        "Abbreviated string representation"
573
        return self.name
574

    
575
    # Automatic class setup support
576

    
577
    isSetup = False
578

    
579
    @classmethod
580
    def checkSetup( cls ):
581
        "Make sure our class and superclasses are set up"
582
        while cls and not getattr( cls, 'isSetup', True ):
583
            cls.setup()
584
            cls.isSetup = True
585
            # Make pylint happy
586
            cls = getattr( type( cls ), '__base__', None )
587

    
588
    @classmethod
589
    def setup( cls ):
590
        "Make sure our class dependencies are available"
591
        pathCheck( 'mnexec', 'ifconfig', moduleName='Mininet')
592

    
593

    
594
class Host( Node ):
595
    "A host is simply a Node"
596
    pass
597

    
598

    
599
class CPULimitedHost( Host ):
600

    
601
    "CPU limited host"
602

    
603
    def __init__( self, name, sched='cfs', **kwargs ):
604
        Host.__init__( self, name, **kwargs )
605
        # Initialize class if necessary
606
        if not CPULimitedHost.inited:
607
            CPULimitedHost.init()
608
        # Create a cgroup and move shell into it
609
        self.cgroup = 'cpu,cpuacct,cpuset:/' + self.name
610
        errFail( 'cgcreate -g ' + self.cgroup )
611
        # We don't add ourselves to a cpuset because you must
612
        # specify the cpu and memory placement first
613
        errFail( 'cgclassify -g cpu,cpuacct:/%s %s' % ( self.name, self.pid ) )
614
        # BL: Setting the correct period/quota is tricky, particularly
615
        # for RT. RT allows very small quotas, but the overhead
616
        # seems to be high. CFS has a mininimum quota of 1 ms, but
617
        # still does better with larger period values.
618
        self.period_us = kwargs.get( 'period_us', 100000 )
619
        self.sched = sched
620
        if self.sched == 'rt':
621
            release = quietRun( 'uname -r' ).strip('\r\n')
622
            output = quietRun( 'grep CONFIG_RT_GROUP_SCHED /boot/config-%s' % release )
623
            if output == '# CONFIG_RT_GROUP_SCHED is not set\n':
624
                error( '\n*** error: please enable RT_GROUP_SCHED in your kernel\n' )
625
                exit( 1 )
626
        self.rtprio = 20
627

    
628
    def cgroupSet( self, param, value, resource='cpu' ):
629
        "Set a cgroup parameter and return its value"
630
        cmd = 'cgset -r %s.%s=%s /%s' % (
631
            resource, param, value, self.name )
632
        quietRun( cmd )
633
        nvalue = int( self.cgroupGet( param, resource ) )
634
        if nvalue != value:
635
            error( '*** error: cgroupSet: %s set to %s instead of %s\n'
636
                   % ( param, nvalue, value ) )
637
        return nvalue
638

    
639
    def cgroupGet( self, param, resource='cpu' ):
640
        "Return value of cgroup parameter"
641
        cmd = 'cgget -r %s.%s /%s' % (
642
            resource, param, self.name )
643
        return int( quietRun( cmd ).split()[ -1 ] )
644

    
645
    def cgroupDel( self ):
646
        "Clean up our cgroup"
647
        # info( '*** deleting cgroup', self.cgroup, '\n' )
648
        _out, _err, exitcode = errRun( 'cgdelete -r ' + self.cgroup )
649
        return exitcode != 0
650

    
651
    def popen( self, *args, **kwargs ):
652
        """Return a Popen() object in node's namespace
653
           args: Popen() args, single list, or string
654
           kwargs: Popen() keyword args"""
655
        # Tell mnexec to execute command in our cgroup
656
        mncmd = [ 'mnexec', '-g', self.name,
657
                  '-da', str( self.pid ) ]
658
        if self.sched == 'rt':
659
            mncmd += [ '-r', str( self.rtprio ) ]
660
        return Host.popen( self, *args, mncmd=mncmd, **kwargs )
661

    
662
    def cleanup( self ):
663
        "Clean up Node, then clean up our cgroup"
664
        super( CPULimitedHost, self ).cleanup()
665
        retry( retries=3, delaySecs=1, fn=self.cgroupDel )
666

    
667
    def chrt( self ):
668
        "Set RT scheduling priority"
669
        quietRun( 'chrt -p %s %s' % ( self.rtprio, self.pid ) )
670
        result = quietRun( 'chrt -p %s' % self.pid )
671
        firstline = result.split( '\n' )[ 0 ]
672
        lastword = firstline.split( ' ' )[ -1 ]
673
        if lastword != 'SCHED_RR':
674
            error( '*** error: could not assign SCHED_RR to %s\n' % self.name )
675
        return lastword
676

    
677
    def rtInfo( self, f ):
678
        "Internal method: return parameters for RT bandwidth"
679
        pstr, qstr = 'rt_period_us', 'rt_runtime_us'
680
        # RT uses wall clock time for period and quota
681
        quota = int( self.period_us * f )
682
        return pstr, qstr, self.period_us, quota
683

    
684
    def cfsInfo( self, f):
685
        "Internal method: return parameters for CFS bandwidth"
686
        pstr, qstr = 'cfs_period_us', 'cfs_quota_us'
687
        # CFS uses wall clock time for period and CPU time for quota.
688
        quota = int( self.period_us * f * numCores() )
689
        period = self.period_us
690
        if f > 0 and quota < 1000:
691
            debug( '(cfsInfo: increasing default period) ' )
692
            quota = 1000
693
            period = int( quota / f / numCores() )
694
        return pstr, qstr, period, quota
695

    
696
    # BL comment:
697
    # This may not be the right API,
698
    # since it doesn't specify CPU bandwidth in "absolute"
699
    # units the way link bandwidth is specified.
700
    # We should use MIPS or SPECINT or something instead.
701
    # Alternatively, we should change from system fraction
702
    # to CPU seconds per second, essentially assuming that
703
    # all CPUs are the same.
704

    
705
    def setCPUFrac( self, f=-1, sched=None):
706
        """Set overall CPU fraction for this host
707
           f: CPU bandwidth limit (fraction)
708
           sched: 'rt' or 'cfs'
709
           Note 'cfs' requires CONFIG_CFS_BANDWIDTH"""
710
        if not f:
711
            return
712
        if not sched:
713
            sched = self.sched
714
        if sched == 'rt':
715
            pstr, qstr, period, quota = self.rtInfo( f )
716
        elif sched == 'cfs':
717
            pstr, qstr, period, quota = self.cfsInfo( f )
718
        else:
719
            return
720
        if quota < 0:
721
            # Reset to unlimited
722
            quota = -1
723
        # Set cgroup's period and quota
724
        self.cgroupSet( pstr, period )
725
        self.cgroupSet( qstr, quota )
726
        if sched == 'rt':
727
            # Set RT priority if necessary
728
            self.chrt()
729
        info( '(%s %d/%dus) ' % ( sched, quota, period ) )
730

    
731
    def setCPUs( self, cores, mems=0 ):
732
        "Specify (real) cores that our cgroup can run on"
733
        if type( cores ) is list:
734
            cores = ','.join( [ str( c ) for c in cores ] )
735
        self.cgroupSet( resource='cpuset', param='cpus',
736
                        value=cores )
737
        # Memory placement is probably not relevant, but we
738
        # must specify it anyway
739
        self.cgroupSet( resource='cpuset', param='mems',
740
                        value=mems)
741
        # We have to do this here after we've specified
742
        # cpus and mems
743
        errFail( 'cgclassify -g cpuset:/%s %s' % (
744
                 self.name, self.pid ) )
745

    
746
    def config( self, cpu=None, cores=None, **params ):
747
        """cpu: desired overall system CPU fraction
748
           cores: (real) core(s) this host can run on
749
           params: parameters for Node.config()"""
750
        r = Node.config( self, **params )
751
        # Was considering cpu={'cpu': cpu , 'sched': sched}, but
752
        # that seems redundant
753
        self.setParam( r, 'setCPUFrac', cpu=cpu )
754
        self.setParam( r, 'setCPUs', cores=cores )
755
        return r
756

    
757
    inited = False
758

    
759
    @classmethod
760
    def init( cls ):
761
        "Initialization for CPULimitedHost class"
762
        mountCgroups()
763
        cls.inited = True
764

    
765
class HostWithPrivateDirs( Host ):
766
    "Host with private directories"
767

    
768
    def __init__( self, name, *args, **kwargs ):
769
        "privateDirs: list of private directory strings or tuples"
770
        self.name = name
771
        self.privateDirs = kwargs.pop( 'privateDirs', [] )
772
        Host.__init__( self, name, *args, **kwargs )
773
        self.mountPrivateDirs()
774

    
775
    def mountPrivateDirs( self ):
776
        "mount private directories"
777
        for directory in self.privateDirs:
778
            if isinstance( directory, tuple ):
779
                # mount given private directory
780
                privateDir = directory[ 1 ] % self.__dict__ 
781
                mountPoint = directory[ 0 ]
782
                self.cmd( 'mkdir -p %s' % privateDir )
783
                self.cmd( 'mkdir -p %s' % mountPoint )
784
                self.cmd( 'mount --bind %s %s' %
785
                               ( privateDir, mountPoint ) )
786
            else:
787
                # mount temporary filesystem on directory
788
                self.cmd( 'mkdir -p %s' % directory ) 
789
                self.cmd( 'mount -n -t tmpfs tmpfs %s' % directory )
790

    
791

    
792

    
793
# Some important things to note:
794
#
795
# The "IP" address which setIP() assigns to the switch is not
796
# an "IP address for the switch" in the sense of IP routing.
797
# Rather, it is the IP address for the control interface,
798
# on the control network, and it is only relevant to the
799
# controller. If you are running in the root namespace
800
# (which is the only way to run OVS at the moment), the
801
# control interface is the loopback interface, and you
802
# normally never want to change its IP address!
803
#
804
# In general, you NEVER want to attempt to use Linux's
805
# network stack (i.e. ifconfig) to "assign" an IP address or
806
# MAC address to a switch data port. Instead, you "assign"
807
# the IP and MAC addresses in the controller by specifying
808
# packets that you want to receive or send. The "MAC" address
809
# reported by ifconfig for a switch data port is essentially
810
# meaningless. It is important to understand this if you
811
# want to create a functional router using OpenFlow.
812

    
813
class Switch( Node ):
814
    """A Switch is a Node that is running (or has execed?)
815
       an OpenFlow switch."""
816

    
817
    portBase = 1  # Switches start with port 1 in OpenFlow
818
    dpidLen = 16  # digits in dpid passed to switch
819

    
820
    def __init__( self, name, dpid=None, opts='', listenPort=None, **params):
821
        """dpid: dpid hex string (or None to derive from name, e.g. s1 -> 1)
822
           opts: additional switch options
823
           listenPort: port to listen on for dpctl connections"""
824
        Node.__init__( self, name, **params )
825
        self.dpid = self.defaultDpid( dpid )
826
        self.opts = opts
827
        self.listenPort = listenPort
828
        if not self.inNamespace:
829
            self.controlIntf = Intf( 'lo', self, port=0 )
830

    
831
    def defaultDpid( self, dpid=None ):
832
        "Return correctly formatted dpid from dpid or switch name (s1 -> 1)"
833
        if dpid:
834
            # Remove any colons and make sure it's a good hex number
835
            dpid = dpid.translate( None, ':' )
836
            assert len( dpid ) <= self.dpidLen and int( dpid, 16 ) >= 0
837
        else:
838
            # Use hex of the first number in the switch name
839
            nums = re.findall( r'\d+', self.name )
840
            if nums:
841
                dpid = hex( int( nums[ 0 ] ) )[ 2: ]
842
            else:
843
                raise Exception( 'Unable to derive default datapath ID - '
844
                                 'please either specify a dpid or use a '
845
                                 'canonical switch name such as s23.' )
846
        return '0' * ( self.dpidLen - len( dpid ) ) + dpid
847

    
848
    def defaultIntf( self ):
849
        "Return control interface"
850
        if self.controlIntf:
851
            return self.controlIntf
852
        else:
853
            return Node.defaultIntf( self )
854

    
855
    def sendCmd( self, *cmd, **kwargs ):
856
        """Send command to Node.
857
           cmd: string"""
858
        kwargs.setdefault( 'printPid', False )
859
        if not self.execed:
860
            return Node.sendCmd( self, *cmd, **kwargs )
861
        else:
862
            error( '*** Error: %s has execed and cannot accept commands' %
863
                   self.name )
864

    
865
    def connected( self ):
866
        "Is the switch connected to a controller? (override this method)"
867
        return False and self  # satisfy pylint
868

    
869
    def __repr__( self ):
870
        "More informative string representation"
871
        intfs = ( ','.join( [ '%s:%s' % ( i.name, i.IP() )
872
                              for i in self.intfList() ] ) )
873
        return '<%s %s: %s pid=%s> ' % (
874
            self.__class__.__name__, self.name, intfs, self.pid )
875

    
876
class UserSwitch( Switch ):
877
    "User-space switch."
878

    
879
    dpidLen = 12
880

    
881
    def __init__( self, name, dpopts='--no-slicing', **kwargs ):
882
        """Init.
883
           name: name for the switch
884
           dpopts: additional arguments to ofdatapath (--no-slicing)"""
885
        Switch.__init__( self, name, **kwargs )
886
        pathCheck( 'ofdatapath', 'ofprotocol',
887
                   moduleName='the OpenFlow reference user switch' +
888
                              '(openflow.org)' )
889
        if self.listenPort:
890
            self.opts += ' --listen=ptcp:%i ' % self.listenPort
891
        else:
892
            self.opts += ' --listen=punix:/tmp/%s.listen' % self.name
893
        self.dpopts = dpopts
894

    
895
    @classmethod
896
    def setup( cls ):
897
        "Ensure any dependencies are loaded; if not, try to load them."
898
        if not os.path.exists( '/dev/net/tun' ):
899
            moduleDeps( add=TUN )
900

    
901
    def dpctl( self, *args ):
902
        "Run dpctl command"
903
        listenAddr = None
904
        if not self.listenPort:
905
            listenAddr = 'unix:/tmp/%s.listen' % self.name
906
        else:
907
            listenAddr = 'tcp:127.0.0.1:%i' % self.listenPort
908
        return self.cmd( 'dpctl ' + ' '.join( args ) +
909
                         ' ' + listenAddr )
910

    
911
    def connected( self ):
912
        "Is the switch connected to a controller?"
913
        status = self.dpctl( 'status' )
914
        return ( 'remote.is-connected=true' in status and
915
                 'local.is-connected=true' in status )
916

    
917
    @staticmethod
918
    def TCReapply( intf ):
919
        """Unfortunately user switch and Mininet are fighting
920
           over tc queuing disciplines. To resolve the conflict,
921
           we re-create the user switch's configuration, but as a
922
           leaf of the TCIntf-created configuration."""
923
        if type( intf ) is TCIntf:
924
            ifspeed = 10000000000 # 10 Gbps
925
            minspeed = ifspeed * 0.001
926

    
927
            res = intf.config( **intf.params )
928

    
929
            if res is None: # link may not have TC parameters
930
                return
931

    
932
            # Re-add qdisc, root, and default classes user switch created, but
933
            # with new parent, as setup by Mininet's TCIntf
934
            parent = res['parent']
935
            intf.tc( "%s qdisc add dev %s " + parent +
936
                     " handle 1: htb default 0xfffe" )
937
            intf.tc( "%s class add dev %s classid 1:0xffff parent 1: htb rate "
938
                     + str(ifspeed) )
939
            intf.tc( "%s class add dev %s classid 1:0xfffe parent 1:0xffff " +
940
                     "htb rate " + str(minspeed) + " ceil " + str(ifspeed) )
941

    
942
    def start( self, controllers ):
943
        """Start OpenFlow reference user datapath.
944
           Log to /tmp/sN-{ofd,ofp}.log.
945
           controllers: list of controller objects"""
946
        # Add controllers
947
        clist = ','.join( [ 'tcp:%s:%d' % ( c.IP(), c.port )
948
                            for c in controllers ] )
949
        ofdlog = '/tmp/' + self.name + '-ofd.log'
950
        ofplog = '/tmp/' + self.name + '-ofp.log'
951
        intfs = [ str( i ) for i in self.intfList() if not i.IP() ]
952
        self.cmd( 'ofdatapath -i ' + ','.join( intfs ) +
953
                  ' punix:/tmp/' + self.name + ' -d %s ' % self.dpid +
954
                  self.dpopts +
955
                  ' 1> ' + ofdlog + ' 2> ' + ofdlog + ' &' )
956
        self.cmd( 'ofprotocol unix:/tmp/' + self.name +
957
                  ' ' + clist +
958
                  ' --fail=closed ' + self.opts +
959
                  ' 1> ' + ofplog + ' 2>' + ofplog + ' &' )
960
        if "no-slicing" not in self.dpopts:
961
            # Only TCReapply if slicing is enable
962
            sleep(1) # Allow ofdatapath to start before re-arranging qdisc's
963
            for intf in self.intfList():
964
                if not intf.IP():
965
                    self.TCReapply( intf )
966

    
967
    def stop( self ):
968
        "Stop OpenFlow reference user datapath."
969
        self.cmd( 'kill %ofdatapath' )
970
        self.cmd( 'kill %ofprotocol' )
971
        self.deleteIntfs()
972

    
973

    
974
class OVSLegacyKernelSwitch( Switch ):
975
    """Open VSwitch legacy kernel-space switch using ovs-openflowd.
976
       Currently only works in the root namespace."""
977

    
978
    def __init__( self, name, dp=None, **kwargs ):
979
        """Init.
980
           name: name for switch
981
           dp: netlink id (0, 1, 2, ...)
982
           defaultMAC: default MAC as unsigned int; random value if None"""
983
        Switch.__init__( self, name, **kwargs )
984
        self.dp = dp if dp else self.name
985
        self.intf = self.dp
986
        if self.inNamespace:
987
            error( "OVSKernelSwitch currently only works"
988
                   " in the root namespace.\n" )
989
            exit( 1 )
990

    
991
    @classmethod
992
    def setup( cls ):
993
        "Ensure any dependencies are loaded; if not, try to load them."
994
        pathCheck( 'ovs-dpctl', 'ovs-openflowd',
995
                   moduleName='Open vSwitch (openvswitch.org)')
996
        moduleDeps( subtract=OF_KMOD, add=OVS_KMOD )
997

    
998
    def start( self, controllers ):
999
        "Start up kernel datapath."
1000
        ofplog = '/tmp/' + self.name + '-ofp.log'
1001
        # Delete local datapath if it exists;
1002
        # then create a new one monitoring the given interfaces
1003
        self.cmd( 'ovs-dpctl del-dp ' + self.dp )
1004
        self.cmd( 'ovs-dpctl add-dp ' + self.dp )
1005
        intfs = [ str( i ) for i in self.intfList() if not i.IP() ]
1006
        self.cmd( 'ovs-dpctl', 'add-if', self.dp, ' '.join( intfs ) )
1007
        # Run protocol daemon
1008
        clist = ','.join( [ 'tcp:%s:%d' % ( c.IP(), c.port )
1009
                            for c in controllers ] )
1010
        self.cmd( 'ovs-openflowd ' + self.dp +
1011
                  ' ' + clist +
1012
                  ' --fail=secure ' + self.opts +
1013
                  ' --datapath-id=' + self.dpid +
1014
                  ' 1>' + ofplog + ' 2>' + ofplog + '&' )
1015
        self.execed = False
1016

    
1017
    def stop( self ):
1018
        "Terminate kernel datapath."
1019
        quietRun( 'ovs-dpctl del-dp ' + self.dp )
1020
        self.cmd( 'kill %ovs-openflowd' )
1021
        self.deleteIntfs()
1022

    
1023

    
1024
class OVSSwitch( Switch ):
1025
    "Open vSwitch switch. Depends on ovs-vsctl."
1026

    
1027
    def __init__( self, name, failMode='secure', datapath='kernel',
1028
                 inband=False, protocols=None, **params ):
1029
        """Init.
1030
           name: name for switch
1031
           failMode: controller loss behavior (secure|open)
1032
           datapath: userspace or kernel mode (kernel|user)
1033
           inband: use in-band control (False)"""
1034
        Switch.__init__( self, name, **params )
1035
        self.failMode = failMode
1036
        self.datapath = datapath
1037
        self.inband = inband
1038
        self.protocols = protocols
1039

    
1040
    @classmethod
1041
    def setup( cls ):
1042
        "Make sure Open vSwitch is installed and working"
1043
        pathCheck( 'ovs-vsctl',
1044
                   moduleName='Open vSwitch (openvswitch.org)')
1045
        # This should no longer be needed, and it breaks
1046
        # with OVS 1.7 which has renamed the kernel module:
1047
        #  moduleDeps( subtract=OF_KMOD, add=OVS_KMOD )
1048
        out, err, exitcode = errRun( 'ovs-vsctl -t 1 show' )
1049
        if exitcode:
1050
            error( out + err +
1051
                   'ovs-vsctl exited with code %d\n' % exitcode +
1052
                   '*** Error connecting to ovs-db with ovs-vsctl\n'
1053
                   'Make sure that Open vSwitch is installed, '
1054
                   'that ovsdb-server is running, and that\n'
1055
                   '"ovs-vsctl show" works correctly.\n'
1056
                   'You may wish to try '
1057
                   '"service openvswitch-switch start".\n' )
1058
            exit( 1 )
1059
        info = quietRun( 'ovs-vsctl --version' )
1060
        cls.OVSVersion =  findall( '\d+\.\d+', info )[ 0 ]
1061

    
1062
    @classmethod
1063
    def isOldOVS( cls ):
1064
        return ( StrictVersion( cls.OVSVersion ) <
1065
             StrictVersion( '1.10' ) )
1066

    
1067
    @classmethod
1068
    def batchShutdown( cls, switches ):
1069
        "Call ovs-vsctl del-br on all OVSSwitches in a list"
1070
        quietRun( 'ovs-vsctl ' +
1071
                  ' -- '.join( '--if-exists del-br %s' % s
1072
                               for s in switches ) )
1073

    
1074
    def dpctl( self, *args ):
1075
        "Run ovs-ofctl command"
1076
        return self.cmd( 'ovs-ofctl', args[ 0 ], self, *args[ 1: ] )
1077

    
1078
    @staticmethod
1079
    def TCReapply( intf ):
1080
        """Unfortunately OVS and Mininet are fighting
1081
           over tc queuing disciplines. As a quick hack/
1082
           workaround, we clear OVS's and reapply our own."""
1083
        if type( intf ) is TCIntf:
1084
            intf.config( **intf.params )
1085

    
1086
    def attach( self, intf ):
1087
        "Connect a data port"
1088
        self.cmd( 'ovs-vsctl add-port', self, intf )
1089
        self.cmd( 'ifconfig', intf, 'up' )
1090
        self.TCReapply( intf )
1091

    
1092
    def detach( self, intf ):
1093
        "Disconnect a data port"
1094
        self.cmd( 'ovs-vsctl del-port', self, intf )
1095

    
1096
    def controllerUUIDs( self ):
1097
        "Return ovsdb UUIDs for our controllers"
1098
        uuids = []
1099
        controllers = self.cmd( 'ovs-vsctl -- get Bridge', self,
1100
                               'Controller' ).strip()
1101
        if controllers.startswith( '[' ) and controllers.endswith( ']' ):
1102
            controllers = controllers[ 1 : -1 ]
1103
            uuids = [ c.strip() for c in controllers.split( ',' ) ]
1104
        return uuids
1105

    
1106
    def connected( self ):
1107
        "Are we connected to at least one of our controllers?"
1108
        results = [ 'true' in self.cmd( 'ovs-vsctl -- get Controller',
1109
                                         uuid, 'is_connected' )
1110
                    for uuid in self.controllerUUIDs() ]
1111
        return reduce( or_, results, False )
1112

    
1113
    def start( self, controllers ):
1114
        "Start up a new OVS OpenFlow switch using ovs-vsctl"
1115
        if self.inNamespace:
1116
            raise Exception(
1117
                'OVS kernel switch does not work in a namespace' )
1118
        # Annoyingly, --if-exists option seems not to work
1119
        self.cmd( 'ovs-vsctl del-br', self )
1120
        int( self.dpid, 16 ) # DPID must be a hex string
1121
        # Interfaces and controllers
1122
        intfs = ' '.join( '-- add-port %s %s ' % ( self, intf ) +
1123
                          '-- set Interface %s ' % intf +
1124
                          'ofport_request=%s ' % self.ports[ intf ]
1125
                         for intf in self.intfList()
1126
                         if self.ports[ intf ] and not intf.IP() )
1127
        clist = ' '.join( '%s:%s:%d' % ( c.protocol, c.IP(), c.port )
1128
                         for c in controllers )
1129
        if self.listenPort:
1130
            clist += ' ptcp:%s' % self.listenPort
1131
        # Construct big ovs-vsctl command for new versions of OVS
1132
        if not self.isOldOVS():
1133
            cmd = ( 'ovs-vsctl add-br %s ' % self +
1134
                    '-- set Bridge %s ' % self +
1135
                    'other_config:datapath-id=%s ' % self.dpid +
1136
                    '-- set-fail-mode %s %s ' % ( self, self.failMode ) +
1137
                    intfs +
1138
                    '-- set-controller %s %s ' % ( self, clist ) )
1139
        # Construct ovs-vsctl commands for old versions of OVS
1140
        else:
1141
            self.cmd( 'ovs-vsctl add-br', self )
1142
            for intf in self.intfList():
1143
                if not intf.IP():
1144
                    self.cmd( 'ovs-vsctl add-port', self, intf )
1145
            cmd = ( 'ovs-vsctl set Bridge %s ' % self +
1146
                    'other_config:datapath-id=%s ' % self.dpid +
1147
                    '-- set-fail-mode %s %s ' % ( self, self.failMode ) +
1148
                    '-- set-controller %s %s ' % ( self, clist ) )
1149
        if not self.inband:
1150
            cmd += ( '-- set bridge %s '
1151
                     'other-config:disable-in-band=true ' % self )
1152
        if self.datapath == 'user':
1153
            cmd += '-- set bridge %s datapath_type=netdev ' % self
1154
        if self.protocols:
1155
            cmd += '-- set bridge %s protocols=%s' % ( self, self.protocols )
1156
        # Reconnect quickly to controllers (1s vs. 15s max_backoff)
1157
        for uuid in self.controllerUUIDs():
1158
            if uuid.count( '-' ) != 4:
1159
                # Doesn't look like a UUID
1160
                continue
1161
            uuid = uuid.strip()
1162
            cmd += '-- set Controller %smax_backoff=1000 ' % uuid
1163
        # Do it!!
1164
        self.cmd( cmd )
1165
        for intf in self.intfList():
1166
            self.TCReapply( intf )
1167

    
1168

    
1169
    def stop( self ):
1170
        "Terminate OVS switch."
1171
        self.cmd( 'ovs-vsctl del-br', self )
1172
        if self.datapath == 'user':
1173
            self.cmd( 'ip link del', self )
1174
        self.deleteIntfs()
1175

    
1176
OVSKernelSwitch = OVSSwitch
1177

    
1178

    
1179
class IVSSwitch(Switch):
1180
    """IVS virtual switch"""
1181

    
1182
    def __init__( self, name, verbose=True, **kwargs ):
1183
        Switch.__init__( self, name, **kwargs )
1184
        self.verbose = verbose
1185

    
1186
    @classmethod
1187
    def setup( cls ):
1188
        "Make sure IVS is installed"
1189
        pathCheck( 'ivs-ctl', 'ivs',
1190
                   moduleName="Indigo Virtual Switch (projectfloodlight.org)" )
1191
        out, err, exitcode = errRun( 'ivs-ctl show' )
1192
        if exitcode:
1193
            error( out + err +
1194
                   'ivs-ctl exited with code %d\n' % exitcode +
1195
                   '*** The openvswitch kernel module might '
1196
                   'not be loaded. Try modprobe openvswitch.\n' )
1197
            exit( 1 )
1198

    
1199
    @classmethod
1200
    def batchShutdown( cls, switches ):
1201
        "Kill each IVS switch, to be waited on later in stop()"
1202
        for switch in switches:
1203
            switch.cmd( 'kill %ivs' )
1204

    
1205
    def start( self, controllers ):
1206
        "Start up a new IVS switch"
1207
        args = ['ivs']
1208
        args.extend( ['--name', self.name] )
1209
        args.extend( ['--dpid', self.dpid] )
1210
        if self.verbose:
1211
            args.extend( ['--verbose'] )
1212
        for intf in self.intfs.values():
1213
            if not intf.IP():
1214
                args.extend( ['-i', intf.name] )
1215
        for c in controllers:
1216
            args.extend( ['-c', '%s:%d' % (c.IP(), c.port)] )
1217
        if self.listenPort:
1218
            args.extend( ['--listen', '127.0.0.1:%i' % self.listenPort] )
1219
        args.append( self.opts )
1220

    
1221
        logfile = '/tmp/ivs.%s.log' % self.name
1222

    
1223
        self.cmd( ' '.join(args) + ' >' + logfile + ' 2>&1 </dev/null &' )
1224

    
1225
    def stop( self ):
1226
        "Terminate IVS switch."
1227
        self.cmd( 'kill %ivs' )
1228
        self.cmd( 'wait' )
1229
        self.deleteIntfs()
1230

    
1231
    def attach( self, intf ):
1232
        "Connect a data port"
1233
        self.cmd( 'ivs-ctl', 'add-port', '--datapath', self.name, intf )
1234

    
1235
    def detach( self, intf ):
1236
        "Disconnect a data port"
1237
        self.cmd( 'ivs-ctl', 'del-port', '--datapath', self.name, intf )
1238

    
1239
    def dpctl( self, *args ):
1240
        "Run dpctl command"
1241
        if not self.listenPort:
1242
            return "can't run dpctl without passive listening port"
1243
        return self.cmd( 'ovs-ofctl ' + ' '.join( args ) +
1244
                         ' tcp:127.0.0.1:%i' % self.listenPort )
1245

    
1246

    
1247
class Controller( Node ):
1248
    """A Controller is a Node that is running (or has execed?) an
1249
       OpenFlow controller."""
1250

    
1251
    def __init__( self, name, inNamespace=False, command='controller',
1252
                  cargs='-v ptcp:%d', cdir=None, ip="127.0.0.1",
1253
                  port=6633, protocol='tcp', **params ):
1254
        self.command = command
1255
        self.cargs = cargs
1256
        self.cdir = cdir
1257
        self.ip = ip
1258
        self.port = port
1259
        self.protocol = protocol
1260
        Node.__init__( self, name, inNamespace=inNamespace,
1261
                       ip=ip, **params  )
1262
        self.checkListening()
1263

    
1264
    def checkListening( self ):
1265
        "Make sure no controllers are running on our port"
1266
        # Verify that Telnet is installed first:
1267
        out, _err, returnCode = errRun( "which telnet" )
1268
        if 'telnet' not in out or returnCode != 0:
1269
            raise Exception( "Error running telnet to check for listening "
1270
                             "controllers; please check that it is "
1271
                             "installed." )
1272
        listening = self.cmd( "echo A | telnet -e A %s %d" %
1273
                              ( self.ip, self.port ) )
1274
        if 'Connected' in listening:
1275
            servers = self.cmd( 'netstat -natp' ).split( '\n' )
1276
            pstr = ':%d ' % self.port
1277
            clist = servers[ 0:1 ] + [ s for s in servers if pstr in s ]
1278
            raise Exception( "Please shut down the controller which is"
1279
                             " running on port %d:\n" % self.port +
1280
                             '\n'.join( clist ) )
1281

    
1282
    def start( self ):
1283
        """Start <controller> <args> on controller.
1284
           Log to /tmp/cN.log"""
1285
        pathCheck( self.command )
1286
        cout = '/tmp/' + self.name + '.log'
1287
        if self.cdir is not None:
1288
            self.cmd( 'cd ' + self.cdir )
1289
        self.cmd( self.command + ' ' + self.cargs % self.port +
1290
                  ' 1>' + cout + ' 2>' + cout + ' &' )
1291
        self.execed = False
1292

    
1293
    def stop( self ):
1294
        "Stop controller."
1295
        self.cmd( 'kill %' + self.command )
1296
        self.terminate()
1297

    
1298
    def IP( self, intf=None ):
1299
        "Return IP address of the Controller"
1300
        if self.intfs:
1301
            ip = Node.IP( self, intf )
1302
        else:
1303
            ip = self.ip
1304
        return ip
1305

    
1306
    def __repr__( self ):
1307
        "More informative string representation"
1308
        return '<%s %s: %s:%s pid=%s> ' % (
1309
            self.__class__.__name__, self.name,
1310
            self.IP(), self.port, self.pid )
1311
    @classmethod
1312
    def isAvailable( self ):
1313
        return quietRun( 'which controller' )
1314

    
1315
class OVSController( Controller ):
1316
    "Open vSwitch controller"
1317
    def __init__( self, name, command='ovs-controller', **kwargs ):
1318
        if quietRun( 'which test-controller' ):
1319
            command = 'test-controller'
1320
        Controller.__init__( self, name, command=command, **kwargs )
1321
    @classmethod
1322
    def isAvailable( self ):
1323
        return quietRun( 'which ovs-controller' ) or quietRun( 'which test-controller' )
1324

    
1325
class NOX( Controller ):
1326
    "Controller to run a NOX application."
1327

    
1328
    def __init__( self, name, *noxArgs, **kwargs ):
1329
        """Init.
1330
           name: name to give controller
1331
           noxArgs: arguments (strings) to pass to NOX"""
1332
        if not noxArgs:
1333
            warn( 'warning: no NOX modules specified; '
1334
                  'running packetdump only\n' )
1335
            noxArgs = [ 'packetdump' ]
1336
        elif type( noxArgs ) not in ( list, tuple ):
1337
            noxArgs = [ noxArgs ]
1338

    
1339
        if 'NOX_CORE_DIR' not in os.environ:
1340
            exit( 'exiting; please set missing NOX_CORE_DIR env var' )
1341
        noxCoreDir = os.environ[ 'NOX_CORE_DIR' ]
1342

    
1343
        Controller.__init__( self, name,
1344
                             command=noxCoreDir + '/nox_core',
1345
                             cargs='--libdir=/usr/local/lib -v -i ptcp:%s ' +
1346
                             ' '.join( noxArgs ),
1347
                             cdir=noxCoreDir,
1348
                             **kwargs )
1349

    
1350

    
1351
class RemoteController( Controller ):
1352
    "Controller running outside of Mininet's control."
1353

    
1354
    def __init__( self, name, ip='127.0.0.1',
1355
                  port=6633, **kwargs):
1356
        """Init.
1357
           name: name to give controller
1358
           ip: the IP address where the remote controller is
1359
           listening
1360
           port: the port where the remote controller is listening"""
1361
        Controller.__init__( self, name, ip=ip, port=port, **kwargs )
1362

    
1363
    def start( self ):
1364
        "Overridden to do nothing."
1365
        return
1366

    
1367
    def stop( self ):
1368
        "Overridden to do nothing."
1369
        return
1370

    
1371
    def checkListening( self ):
1372
        "Warn if remote controller is not accessible"
1373
        listening = self.cmd( "echo A | telnet -e A %s %d" %
1374
                              ( self.ip, self.port ) )
1375
        if 'Connected' not in listening:
1376
            warn( "Unable to contact the remote controller"
1377
                  " at %s:%d\n" % ( self.ip, self.port ) )
1378

    
1379
def DefaultController( name, order=[ Controller, OVSController ], **kwargs ):
1380
    "find any controller that is available and run it"
1381
    for controller in order:
1382
        if controller.isAvailable():
1383
            return controller( name, **kwargs )