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|
#!/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, find_route
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(5)
#
# 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")
#
# A neighbor entry that has no associated FIB-entry
#
arp_no_fib = VppNeighbor(self,
self.pg1.sw_if_index,
self.pg1.remote_hosts[4].mac,
self.pg1.remote_hosts[4].ip4,
is_no_fib_entry=1)
arp_no_fib.add_vpp_config()
#
# check we have the neighbor, but no route
#
self.assertTrue(find_nbr(self,
self.pg1.sw_if_index,
self.pg1._remote_hosts[4].ip4))
self.assertFalse(find_route(self,
self.pg1._remote_hosts[4].ip4,
32))
#
# 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)
|
