| #!/usr/bin/env python3 |
| """NAT44 ED output-feature tests""" |
| |
| import random |
| import unittest |
| from scapy.layers.inet import ICMP, Ether, IP, TCP |
| from scapy.packet import Raw |
| from scapy.data import IP_PROTOS |
| from framework import VppTestCase, VppTestRunner |
| from vpp_papi import VppEnum |
| |
| |
| def get_nat44_ed_in2out_worker_index(ip, vpp_worker_count): |
| if 0 == vpp_worker_count: |
| return 0 |
| numeric = socket.inet_aton(ip) |
| numeric = struct.unpack("!L", numeric)[0] |
| numeric = socket.htonl(numeric) |
| h = numeric + (numeric >> 8) + (numeric >> 16) + (numeric >> 24) |
| return 1 + h % vpp_worker_count |
| |
| |
| class TestNAT44EDOutput(VppTestCase): |
| """ NAT44 ED output feature Test Case """ |
| max_sessions = 1024 |
| |
| @classmethod |
| def setUpClass(cls): |
| super().setUpClass() |
| cls.create_pg_interfaces(range(2)) |
| cls.interfaces = list(cls.pg_interfaces) |
| |
| @classmethod |
| def tearDownClass(cls): |
| super().tearDownClass() |
| |
| def setUp(self): |
| super().setUp() |
| for i in self.interfaces: |
| i.admin_up() |
| i.config_ip4() |
| i.resolve_arp() |
| self.vapi.nat44_ed_plugin_enable_disable(sessions=self.max_sessions, |
| enable=1) |
| |
| def tearDown(self): |
| if not self.vpp_dead: |
| self.logger.debug(self.vapi.cli("show nat44 sessions")) |
| super().tearDown() |
| if not self.vpp_dead: |
| for i in self.pg_interfaces: |
| i.unconfig_ip4() |
| i.admin_down() |
| self.vapi.nat44_ed_plugin_enable_disable(enable=0) |
| |
| def test_static_dynamic(self): |
| """ Create static mapping which matches existing dynamic mapping """ |
| |
| config = self.vapi.nat44_show_running_config() |
| old_timeouts = config.timeouts |
| new_transitory = 2 |
| self.vapi.nat_set_timeouts( |
| udp=old_timeouts.udp, |
| tcp_established=old_timeouts.tcp_established, |
| icmp=old_timeouts.icmp, |
| tcp_transitory=new_transitory) |
| |
| local_host = self.pg0.remote_ip4 |
| remote_host = self.pg1.remote_ip4 |
| nat_intf = self.pg1 |
| outside_addr = nat_intf.local_ip4 |
| |
| self.vapi.nat44_add_del_address_range(first_ip_address=outside_addr, |
| last_ip_address=outside_addr, |
| vrf_id=0xffffffff, |
| is_add=1, |
| flags=0) |
| self.vapi.nat44_interface_add_del_feature( |
| sw_if_index=self.pg0.sw_if_index, |
| is_add=1) |
| self.vapi.nat44_interface_add_del_feature( |
| sw_if_index=self.pg0.sw_if_index, |
| flags=VppEnum.vl_api_nat_config_flags_t.NAT_IS_INSIDE, is_add=1) |
| self.vapi.nat44_ed_add_del_output_interface( |
| sw_if_index=self.pg1.sw_if_index, |
| is_add=1) |
| |
| thread_index = get_nat44_ed_in2out_worker_index( |
| local_host, self.vpp_worker_count) |
| port_per_thread = int((0xffff-1024) / max(1, self.vpp_worker_count)) |
| local_sport = 1024 + random.randint(1, port_per_thread) |
| if self.vpp_worker_count > 0: |
| local_sport += port_per_thread * (thread_index - 1) |
| |
| remote_dport = 10000 |
| |
| pg0 = self.pg0 |
| pg1 = self.pg1 |
| |
| # first setup a dynamic TCP session |
| |
| # SYN packet in->out |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport, flags="S")) |
| p = self.send_and_expect(pg0, [p], pg1)[0] |
| |
| self.assertEqual(p[IP].src, outside_addr) |
| self.assertEqual(p[TCP].sport, local_sport) |
| outside_port = p[TCP].sport |
| |
| # SYN+ACK packet out->in |
| p = (Ether(src=pg1.remote_mac, dst=pg1.local_mac) / |
| IP(src=remote_host, dst=outside_addr) / |
| TCP(sport=remote_dport, dport=outside_port, flags="SA")) |
| self.send_and_expect(pg1, [p], pg0) |
| |
| # ACK packet in->out |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport, flags="A")) |
| self.send_and_expect(pg0, [p], pg1) |
| |
| # now we have a session up, create a conflicting static mapping |
| self.vapi.nat44_add_del_static_mapping( |
| is_add=1, |
| local_ip_address=local_host, |
| external_ip_address=outside_addr, |
| external_sw_if_index=0xffffffff, |
| local_port=local_sport, |
| external_port=outside_port, |
| protocol=IP_PROTOS.tcp, |
| flags=VppEnum.vl_api_nat_config_flags_t.NAT_IS_OUT2IN_ONLY) |
| |
| sessions = self.vapi.nat44_user_session_dump(local_host, 0) |
| self.assertEqual(1, len(sessions)) |
| |
| # now send some more data over existing session - it should pass |
| |
| # in->out |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport) / |
| Raw("zippity zap")) |
| self.send_and_expect(pg0, [p], pg1) |
| |
| # out->in |
| p = (Ether(src=pg1.remote_mac, dst=pg1.local_mac) / |
| IP(src=remote_host, dst=outside_addr) / |
| TCP(sport=remote_dport, dport=outside_port) / |
| Raw("flippity flop")) |
| self.send_and_expect(pg1, [p], pg0) |
| |
| # now close the session |
| |
| # FIN packet in -> out |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport, flags="FA", seq=100, |
| ack=300)) |
| self.send_and_expect(pg0, [p], pg1) |
| |
| # FIN+ACK packet out -> in |
| p = (Ether(src=pg1.remote_mac, dst=pg1.local_mac) / |
| IP(src=remote_host, dst=outside_addr) / |
| TCP(sport=remote_dport, dport=outside_port, flags="FA", seq=300, |
| ack=101)) |
| self.send_and_expect(pg1, [p], pg0) |
| |
| # ACK packet in -> out |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport, flags="A", seq=101, |
| ack=301)) |
| self.send_and_expect(pg0, [p], pg1) |
| |
| # session now in transitory timeout |
| # try SYN packet in->out - should be dropped |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport, flags="S")) |
| pg0.add_stream(p) |
| self.pg_enable_capture() |
| self.pg_start() |
| |
| self.sleep(new_transitory, "wait for transitory timeout") |
| pg0.assert_nothing_captured(0) |
| |
| # session should still exist |
| sessions = self.vapi.nat44_user_session_dump(pg0.remote_ip4, 0) |
| self.assertEqual(1, len(sessions)) |
| |
| # send FIN+ACK packet in->out - will cause session to be wiped |
| # but won't create a new session |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport, flags="FA", seq=300, |
| ack=101)) |
| pg1.add_stream(p) |
| self.pg_enable_capture() |
| self.pg_start() |
| pg0.assert_nothing_captured(0) |
| |
| sessions = self.vapi.nat44_user_session_dump(pg0.remote_ip4, 0) |
| self.assertEqual(0, len(sessions)) |
| |
| # create a new session and make sure the outside port is remapped |
| # SYN packet in->out |
| |
| p = (Ether(src=pg0.remote_mac, dst=pg0.local_mac) / |
| IP(src=local_host, dst=remote_host) / |
| TCP(sport=local_sport, dport=remote_dport, flags="S")) |
| p = self.send_and_expect(pg0, [p], pg1)[0] |
| |
| self.assertEqual(p[IP].src, outside_addr) |
| self.assertNotEqual(p[TCP].sport, local_sport) |
| |
| # make sure static mapping works and creates a new session |
| # SYN packet out->in |
| p = (Ether(src=pg1.remote_mac, dst=pg1.local_mac) / |
| IP(src=remote_host, dst=outside_addr) / |
| TCP(sport=remote_dport, dport=outside_port, flags="S")) |
| self.send_and_expect(pg1, [p], pg0) |
| |
| sessions = self.vapi.nat44_user_session_dump(pg0.remote_ip4, 0) |
| self.assertEqual(2, len(sessions)) |
| |
| |
| if __name__ == '__main__': |
| unittest.main(testRunner=VppTestRunner) |