1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
|
#!/usr/bin/env python
import unittest
from socket import AF_INET, AF_INET6, inet_pton
from framework import VppTestCase, VppTestRunner
from vpp_neighbor import VppNeighbor, find_nbr
from vpp_ip_route import VppIpRoute, VppRoutePath
from scapy.packet import Raw
from scapy.layers.l2 import Ether, ARP
from scapy.layers.inet import IP, UDP
from scapy.contrib.mpls import MPLS
# not exported by scapy, so redefined here
arp_opts = {"who-has": 1, "is-at": 2}
class ARPTestCase(VppTestCase):
""" ARP Test Case """
def setUp(self):
super(ARPTestCase, self).setUp()
# create 3 pg interfaces
self.create_pg_interfaces(range(4))
# pg0 configured with ip4 and 6 addresses used for input
# pg1 configured with ip4 and 6 addresses used for output
# pg2 is unnumbered to pg0
for i in self.pg_interfaces:
i.admin_up()
self.pg0.config_ip4()
self.pg0.config_ip6()
self.pg0.resolve_arp()
self.pg1.config_ip4()
self.pg1.config_ip6()
# pg3 in a different VRF
self.pg3.set_table_ip4(1)
self.pg3.config_ip4()
def tearDown(self):
super(ARPTestCase, self).tearDown()
for i in self.pg_interfaces:
i.unconfig_ip4()
i.unconfig_ip6()
i.admin_down()
def verify_arp_req(self, rx, smac, sip, dip):
ether = rx[Ether]
self.assertEqual(ether.dst, "ff:ff:ff:ff:ff:ff")
self.assertEqual(ether.src, smac)
arp = rx[ARP]
self.assertEqual(arp.hwtype, 1)
self.assertEqual(arp.ptype, 0x800)
self.assertEqual(arp.hwlen, 6)
self.assertEqual(arp.plen, 4)
self.assertEqual(arp.op, arp_opts["who-has"])
self.assertEqual(arp.hwsrc, smac)
self.assertEqual(arp.hwdst, "00:00:00:00:00:00")
self.assertEqual(arp.psrc, sip)
self.assertEqual(arp.pdst, dip)
def verify_arp_resp(self, rx, smac, dmac, sip, dip):
ether = rx[Ether]
self.assertEqual(ether.dst, dmac)
self.assertEqual(ether.src, smac)
arp = rx[ARP]
self.assertEqual(arp.hwtype, 1)
self.assertEqual(arp.ptype, 0x800)
self.assertEqual(arp.hwlen, 6)
self.assertEqual(arp.plen, 4)
self.assertEqual(arp.op, arp_opts["is-at"])
self.assertEqual(arp.hwsrc, smac)
self.assertEqual(arp.hwdst, dmac)
self.assertEqual(arp.psrc, sip)
self.assertEqual(arp.pdst, dip)
def verify_ip(self, rx, smac, dmac, sip, dip):
ether = rx[Ether]
self.assertEqual(ether.dst, dmac)
self.assertEqual(ether.src, smac)
ip = rx[IP]
self.assertEqual(ip.src, sip)
self.assertEqual(ip.dst, dip)
def verify_ip_o_mpls(self, rx, smac, dmac, label, sip, dip):
ether = rx[Ether]
self.assertEqual(ether.dst, dmac)
self.assertEqual(ether.src, smac)
mpls = rx[MPLS]
self.assertTrue(mpls.label, label)
ip = rx[IP]
self.assertEqual(ip.src, sip)
self.assertEqual(ip.dst, dip)
def send_and_assert_no_replies(self, intf, pkts, remark):
intf.add_stream(pkts)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
for i in self.pg_interfaces:
i.assert_nothing_captured(remark=remark)
def test_arp(self):
""" ARP """
#
# Generate some hosts on the LAN
#
self.pg1.generate_remote_hosts(4)
#
# Send IP traffic to one of these unresolved hosts.
# expect the generation of an ARP request
#
p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
IP(src=self.pg0.remote_ip4, dst=self.pg1._remote_hosts[1].ip4) /
UDP(sport=1234, dport=1234) /
Raw())
self.pg0.add_stream(p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg1.get_capture(1)
self.verify_arp_req(rx[0],
self.pg1.local_mac,
self.pg1.local_ip4,
self.pg1._remote_hosts[1].ip4)
#
# And a dynamic ARP entry for host 1
#
dyn_arp = VppNeighbor(self,
self.pg1.sw_if_index,
self.pg1.remote_hosts[1].mac,
self.pg1.remote_hosts[1].ip4)
dyn_arp.add_vpp_config()
#
# now we expect IP traffic forwarded
#
dyn_p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
IP(src=self.pg0.remote_ip4,
dst=self.pg1._remote_hosts[1].ip4) /
UDP(sport=1234, dport=1234) /
Raw())
self.pg0.add_stream(dyn_p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg1.get_capture(1)
self.verify_ip(rx[0],
self.pg1.local_mac,
self.pg1.remote_hosts[1].mac,
self.pg0.remote_ip4,
self.pg1._remote_hosts[1].ip4)
#
# And a Static ARP entry for host 2
#
static_arp = VppNeighbor(self,
self.pg1.sw_if_index,
self.pg1.remote_hosts[2].mac,
self.pg1.remote_hosts[2].ip4,
is_static=1)
static_arp.add_vpp_config()
static_p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
IP(src=self.pg0.remote_ip4,
dst=self.pg1._remote_hosts[2].ip4) /
UDP(sport=1234, dport=1234) /
Raw())
self.pg0.add_stream(static_p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg1.get_capture(1)
self.verify_ip(rx[0],
self.pg1.local_mac,
self.pg1.remote_hosts[2].mac,
self.pg0.remote_ip4,
self.pg1._remote_hosts[2].ip4)
#
# flap the link. dynamic ARPs get flush, statics don't
#
self.pg1.admin_down()
self.pg1.admin_up()
self.pg0.add_stream(static_p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg1.get_capture(1)
self.verify_ip(rx[0],
self.pg1.local_mac,
self.pg1.remote_hosts[2].mac,
self.pg0.remote_ip4,
self.pg1._remote_hosts[2].ip4)
self.pg0.add_stream(dyn_p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg1.get_capture(1)
self.verify_arp_req(rx[0],
self.pg1.local_mac,
self.pg1.local_ip4,
self.pg1._remote_hosts[1].ip4)
#
# Send an ARP request from one of the so-far unlearned remote hosts
#
p = (Ether(dst="ff:ff:ff:ff:ff:ff",
src=self.pg1._remote_hosts[3].mac) /
ARP(op="who-has",
hwsrc=self.pg1._remote_hosts[3].mac,
pdst=self.pg1.local_ip4,
psrc=self.pg1._remote_hosts[3].ip4))
self.pg1.add_stream(p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg1.get_capture(1)
self.verify_arp_resp(rx[0],
self.pg1.local_mac,
self.pg1._remote_hosts[3].mac,
self.pg1.local_ip4,
self.pg1._remote_hosts[3].ip4)
#
# VPP should have learned the mapping for the remote host
#
self.assertTrue(find_nbr(self,
self.pg1.sw_if_index,
self.pg1._remote_hosts[3].ip4))
#
# ERROR Cases
# 1 - don't respond to ARP request for address not within the
# interface's sub-net
#
p = (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg0.remote_mac) /
ARP(op="who-has",
hwsrc=self.pg0.remote_mac,
pdst="10.10.10.3",
psrc=self.pg0.remote_ip4))
self.send_and_assert_no_replies(self.pg0, p,
"ARP req for non-local destination")
#
# 2 - don't respond to ARP request from an address not within the
# interface's sub-net
#
p = (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg0.remote_mac) /
ARP(op="who-has",
hwsrc=self.pg0.remote_mac,
psrc="10.10.10.3",
pdst=self.pg0.local_ip4))
self.send_and_assert_no_replies(self.pg0, p,
"ARP req for non-local source")
#
# 3 - don't respond to ARP request from an address that belongs to
# the router
#
p = (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg0.remote_mac) /
ARP(op="who-has",
hwsrc=self.pg0.remote_mac,
psrc=self.pg0.local_ip4,
pdst=self.pg0.local_ip4))
self.send_and_assert_no_replies(self.pg0, p,
"ARP req for non-local source")
#
# 4 - don't respond to ARP requests that has mac source different
# from ARP request HW source
# the router
#
p = (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg0.remote_mac) /
ARP(op="who-has",
hwsrc="00:00:00:DE:AD:BE",
psrc=self.pg0.remote_ip4,
pdst=self.pg0.local_ip4))
self.send_and_assert_no_replies(self.pg0, p,
"ARP req for non-local source")
#
# cleanup
#
dyn_arp.remove_vpp_config()
static_arp.remove_vpp_config()
def test_proxy_arp(self):
""" Proxy ARP """
#
# Proxy ARP rewquest packets for each interface
#
arp_req_pg2 = (Ether(src=self.pg2.remote_mac,
dst="ff:ff:ff:ff:ff:ff") /
ARP(op="who-has",
hwsrc=self.pg2.remote_mac,
pdst="10.10.10.3",
psrc=self.pg1.remote_ip4))
arp_req_pg0 = (Ether(src=self.pg0.remote_mac,
dst="ff:ff:ff:ff:ff:ff") /
ARP(op="who-has",
hwsrc=self.pg0.remote_mac,
pdst="10.10.10.3",
psrc=self.pg0.remote_ip4))
arp_req_pg1 = (Ether(src=self.pg1.remote_mac,
dst="ff:ff:ff:ff:ff:ff") /
ARP(op="who-has",
hwsrc=self.pg1.remote_mac,
pdst="10.10.10.3",
psrc=self.pg1.remote_ip4))
arp_req_pg3 = (Ether(src=self.pg3.remote_mac,
dst="ff:ff:ff:ff:ff:ff") /
ARP(op="who-has",
hwsrc=self.pg3.remote_mac,
pdst="10.10.10.3",
psrc=self.pg3.remote_ip4))
#
# Configure Proxy ARP for 10.10.10.0 -> 10.10.10.124
#
self.vapi.proxy_arp_add_del(inet_pton(AF_INET, "10.10.10.2"),
inet_pton(AF_INET, "10.10.10.124"))
#
# No responses are sent when the interfaces are not enabled for proxy
# ARP
#
self.send_and_assert_no_replies(self.pg0, arp_req_pg0,
"ARP req from unconfigured interface")
self.send_and_assert_no_replies(self.pg2, arp_req_pg2,
"ARP req from unconfigured interface")
#
# Make pg2 un-numbered to pg1
# still won't reply.
#
self.pg2.set_unnumbered(self.pg1.sw_if_index)
self.send_and_assert_no_replies(self.pg2, arp_req_pg2,
"ARP req from unnumbered interface")
#
# Enable each interface to reply to proxy ARPs
#
for i in self.pg_interfaces:
i.set_proxy_arp()
#
# Now each of the interfaces should reply to a request to a proxied
# address
#
self.pg0.add_stream(arp_req_pg0)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg0.get_capture(1)
self.verify_arp_resp(rx[0],
self.pg0.local_mac,
self.pg0.remote_mac,
"10.10.10.3",
self.pg0.remote_ip4)
self.pg1.add_stream(arp_req_pg1)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg1.get_capture(1)
self.verify_arp_resp(rx[0],
self.pg1.local_mac,
self.pg1.remote_mac,
"10.10.10.3",
self.pg1.remote_ip4)
self.pg2.add_stream(arp_req_pg2)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg2.get_capture(1)
self.verify_arp_resp(rx[0],
self.pg2.local_mac,
self.pg2.remote_mac,
"10.10.10.3",
self.pg1.remote_ip4)
#
# A request for an address out of the configured range
#
arp_req_pg1_hi = (Ether(src=self.pg1.remote_mac,
dst="ff:ff:ff:ff:ff:ff") /
ARP(op="who-has",
hwsrc=self.pg1.remote_mac,
pdst="10.10.10.125",
psrc=self.pg1.remote_ip4))
self.send_and_assert_no_replies(self.pg1, arp_req_pg1_hi,
"ARP req out of range HI")
arp_req_pg1_low = (Ether(src=self.pg1.remote_mac,
dst="ff:ff:ff:ff:ff:ff") /
ARP(op="who-has",
hwsrc=self.pg1.remote_mac,
pdst="10.10.10.1",
psrc=self.pg1.remote_ip4))
self.send_and_assert_no_replies(self.pg1, arp_req_pg1_low,
"ARP req out of range Low")
#
# Request for an address in the proxy range but from an interface
# in a different VRF
#
self.send_and_assert_no_replies(self.pg3, arp_req_pg3,
"ARP req from different VRF")
#
# Disable Each interface for proxy ARP
# - expect none to respond
#
for i in self.pg_interfaces:
i.set_proxy_arp(0)
self.send_and_assert_no_replies(self.pg0, arp_req_pg0,
"ARP req from disable")
self.send_and_assert_no_replies(self.pg1, arp_req_pg1,
"ARP req from disable")
self.send_and_assert_no_replies(self.pg2, arp_req_pg2,
"ARP req from disable")
#
# clean up on interface 2
#
self.pg2.set_unnumbered(self.pg1.sw_if_index)
def test_mpls(self):
""" MPLS """
#
# Interface 2 does not yet have ip4 config
#
self.pg2.config_ip4()
self.pg2.generate_remote_hosts(2)
#
# Add a reoute with out going label via an ARP unresolved next-hop
#
ip_10_0_0_1 = VppIpRoute(self, "10.0.0.1", 32,
[VppRoutePath(self.pg2.remote_hosts[1].ip4,
self.pg2.sw_if_index,
labels=[55])])
ip_10_0_0_1.add_vpp_config()
#
# packets should generate an ARP request
#
p = (Ether(src=self.pg0.remote_mac,
dst=self.pg0.local_mac) /
IP(src=self.pg0.remote_ip4, dst="10.0.0.1") /
UDP(sport=1234, dport=1234) /
Raw('\xa5' * 100))
self.pg0.add_stream(p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg2.get_capture(1)
self.verify_arp_req(rx[0],
self.pg2.local_mac,
self.pg2.local_ip4,
self.pg2._remote_hosts[1].ip4)
#
# now resolve the neighbours
#
self.pg2.configure_ipv4_neighbors()
#
# Now packet should be properly MPLS encapped.
# This verifies that MPLS link-type adjacencies are completed
# when the ARP entry resolves
#
self.pg0.add_stream(p)
self.pg_enable_capture(self.pg_interfaces)
self.pg_start()
rx = self.pg2.get_capture(1)
self.verify_ip_o_mpls(rx[0],
self.pg2.local_mac,
self.pg2.remote_hosts[1].mac,
55,
self.pg0.remote_ip4,
"10.0.0.1")
if __name__ == '__main__':
unittest.main(testRunner=VppTestRunner)
|
