2 """NAT44 ED output-feature tests"""
6 from scapy.layers.inet import ICMP, Ether, IP, TCP
7 from scapy.packet import Raw
8 from scapy.data import IP_PROTOS
9 from framework import VppTestCase, VppTestRunner
10 from vpp_papi import VppEnum
13 def get_nat44_ed_in2out_worker_index(ip, vpp_worker_count):
14 if 0 == vpp_worker_count:
16 numeric = socket.inet_aton(ip)
17 numeric = struct.unpack("!L", numeric)[0]
18 numeric = socket.htonl(numeric)
19 h = numeric + (numeric >> 8) + (numeric >> 16) + (numeric >> 24)
20 return 1 + h % vpp_worker_count
23 class TestNAT44EDOutput(VppTestCase):
24 """NAT44 ED output feature Test Case"""
31 cls.create_pg_interfaces(range(2))
32 cls.interfaces = list(cls.pg_interfaces)
35 def tearDownClass(cls):
36 super().tearDownClass()
40 for i in self.interfaces:
44 self.vapi.nat44_ed_plugin_enable_disable(sessions=self.max_sessions, enable=1)
48 self.logger.debug(self.vapi.cli("show nat44 sessions"))
51 for i in self.pg_interfaces:
54 self.vapi.nat44_ed_plugin_enable_disable(enable=0)
56 def test_static_dynamic(self):
57 """Create static mapping which matches existing dynamic mapping"""
59 config = self.vapi.nat44_show_running_config()
60 old_timeouts = config.timeouts
62 self.vapi.nat_set_timeouts(
64 tcp_established=old_timeouts.tcp_established,
65 icmp=old_timeouts.icmp,
66 tcp_transitory=new_transitory,
69 local_host = self.pg0.remote_ip4
70 remote_host = self.pg1.remote_ip4
72 outside_addr = nat_intf.local_ip4
74 self.vapi.nat44_add_del_address_range(
75 first_ip_address=outside_addr,
76 last_ip_address=outside_addr,
81 self.vapi.nat44_interface_add_del_feature(
82 sw_if_index=self.pg0.sw_if_index, is_add=1
84 self.vapi.nat44_interface_add_del_feature(
85 sw_if_index=self.pg0.sw_if_index,
86 flags=VppEnum.vl_api_nat_config_flags_t.NAT_IS_INSIDE,
89 self.vapi.nat44_ed_add_del_output_interface(
90 sw_if_index=self.pg1.sw_if_index, is_add=1
93 thread_index = get_nat44_ed_in2out_worker_index(
94 local_host, self.vpp_worker_count
96 port_per_thread = int((0xFFFF - 1024) / max(1, self.vpp_worker_count))
97 local_sport = 1024 + random.randint(1, port_per_thread)
98 if self.vpp_worker_count > 0:
99 local_sport += port_per_thread * (thread_index - 1)
106 # first setup a dynamic TCP session
110 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
111 / IP(src=local_host, dst=remote_host)
112 / TCP(sport=local_sport, dport=remote_dport, flags="S")
114 p = self.send_and_expect(pg0, [p], pg1)[0]
116 self.assertEqual(p[IP].src, outside_addr)
117 self.assertEqual(p[TCP].sport, local_sport)
118 outside_port = p[TCP].sport
120 # SYN+ACK packet out->in
122 Ether(src=pg1.remote_mac, dst=pg1.local_mac)
123 / IP(src=remote_host, dst=outside_addr)
124 / TCP(sport=remote_dport, dport=outside_port, flags="SA")
126 self.send_and_expect(pg1, [p], pg0)
130 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
131 / IP(src=local_host, dst=remote_host)
132 / TCP(sport=local_sport, dport=remote_dport, flags="A")
134 self.send_and_expect(pg0, [p], pg1)
136 # now we have a session up, create a conflicting static mapping
137 self.vapi.nat44_add_del_static_mapping(
139 local_ip_address=local_host,
140 external_ip_address=outside_addr,
141 external_sw_if_index=0xFFFFFFFF,
142 local_port=local_sport,
143 external_port=outside_port,
144 protocol=IP_PROTOS.tcp,
145 flags=VppEnum.vl_api_nat_config_flags_t.NAT_IS_OUT2IN_ONLY,
148 sessions = self.vapi.nat44_user_session_dump(local_host, 0)
149 self.assertEqual(1, len(sessions))
151 # now send some more data over existing session - it should pass
155 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
156 / IP(src=local_host, dst=remote_host)
157 / TCP(sport=local_sport, dport=remote_dport)
160 self.send_and_expect(pg0, [p], pg1)
164 Ether(src=pg1.remote_mac, dst=pg1.local_mac)
165 / IP(src=remote_host, dst=outside_addr)
166 / TCP(sport=remote_dport, dport=outside_port)
167 / Raw("flippity flop")
169 self.send_and_expect(pg1, [p], pg0)
171 # now close the session
173 # FIN packet in -> out
175 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
176 / IP(src=local_host, dst=remote_host)
177 / TCP(sport=local_sport, dport=remote_dport, flags="FA", seq=100, ack=300)
179 self.send_and_expect(pg0, [p], pg1)
181 # FIN+ACK packet out -> in
183 Ether(src=pg1.remote_mac, dst=pg1.local_mac)
184 / IP(src=remote_host, dst=outside_addr)
185 / TCP(sport=remote_dport, dport=outside_port, flags="FA", seq=300, ack=101)
187 self.send_and_expect(pg1, [p], pg0)
189 # ACK packet in -> out
191 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
192 / IP(src=local_host, dst=remote_host)
193 / TCP(sport=local_sport, dport=remote_dport, flags="A", seq=101, ack=301)
195 self.send_and_expect(pg0, [p], pg1)
197 # session now in transitory timeout
198 # try SYN packet in->out - should be dropped
200 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
201 / IP(src=local_host, dst=remote_host)
202 / TCP(sport=local_sport, dport=remote_dport, flags="S")
205 self.pg_enable_capture()
208 self.sleep(new_transitory, "wait for transitory timeout")
209 pg0.assert_nothing_captured(0)
211 # session should still exist
212 sessions = self.vapi.nat44_user_session_dump(pg0.remote_ip4, 0)
213 self.assertEqual(1, len(sessions))
215 # send FIN+ACK packet in->out - will cause session to be wiped
216 # but won't create a new session
218 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
219 / IP(src=local_host, dst=remote_host)
220 / TCP(sport=local_sport, dport=remote_dport, flags="FA", seq=300, ack=101)
223 self.pg_enable_capture()
225 pg0.assert_nothing_captured(0)
227 sessions = self.vapi.nat44_user_session_dump(pg0.remote_ip4, 0)
228 self.assertEqual(0, len(sessions))
230 # create a new session and make sure the outside port is remapped
234 Ether(src=pg0.remote_mac, dst=pg0.local_mac)
235 / IP(src=local_host, dst=remote_host)
236 / TCP(sport=local_sport, dport=remote_dport, flags="S")
238 p = self.send_and_expect(pg0, [p], pg1)[0]
240 self.assertEqual(p[IP].src, outside_addr)
241 self.assertNotEqual(p[TCP].sport, local_sport)
243 # make sure static mapping works and creates a new session
246 Ether(src=pg1.remote_mac, dst=pg1.local_mac)
247 / IP(src=remote_host, dst=outside_addr)
248 / TCP(sport=remote_dport, dport=outside_port, flags="S")
250 self.send_and_expect(pg1, [p], pg0)
252 sessions = self.vapi.nat44_user_session_dump(pg0.remote_ip4, 0)
253 self.assertEqual(2, len(sessions))
256 if __name__ == "__main__":
257 unittest.main(testRunner=VppTestRunner)