#!/usr/bin/env python3 import socket import scapy.compat from scapy.layers.l2 import Ether from scapy.layers.inet import ICMP, IP, TCP, UDP from scapy.layers.ipsec import SecurityAssociation, ESP from util import ppp, ppc from template_ipsec import TemplateIpsec from vpp_ipsec import VppIpsecSA, VppIpsecSpd, VppIpsecSpdEntry, VppIpsecSpdItfBinding from vpp_ip_route import VppIpRoute, VppRoutePath from vpp_ip import DpoProto from vpp_papi import VppEnum class IPSecNATTestCase(TemplateIpsec): """IPSec/NAT TUNNEL MODE:: public network | private network --- encrypt --- plain --- |pg0| <------- |VPP| <------ |pg1| --- --- --- --- decrypt --- plain --- |pg0| -------> |VPP| ------> |pg1| --- --- --- """ tcp_port_in = 6303 tcp_port_out = 6303 udp_port_in = 6304 udp_port_out = 6304 icmp_id_in = 6305 icmp_id_out = 6305 @classmethod def setUpClass(cls): super(IPSecNATTestCase, cls).setUpClass() @classmethod def tearDownClass(cls): super(IPSecNATTestCase, cls).tearDownClass() def setUp(self): super(IPSecNATTestCase, self).setUp() self.tun_if = self.pg0 self.tun_spd = VppIpsecSpd(self, self.tun_spd_id) self.tun_spd.add_vpp_config() VppIpsecSpdItfBinding(self, self.tun_spd, self.tun_if).add_vpp_config() p = self.ipv4_params self.config_esp_tun(p) self.logger.info(self.vapi.ppcli("show ipsec all")) d = DpoProto.DPO_PROTO_IP6 if p.is_ipv6 else DpoProto.DPO_PROTO_IP4 VppIpRoute( self, p.remote_tun_if_host, p.addr_len, [VppRoutePath(self.tun_if.remote_addr[p.addr_type], 0xFFFFFFFF, proto=d)], ).add_vpp_config() def tearDown(self): super(IPSecNATTestCase, self).tearDown() def create_stream_plain(self, src_mac, dst_mac, src_ip, dst_ip): return [ # TCP Ether(src=src_mac, dst=dst_mac) / IP(src=src_ip, dst=dst_ip) / TCP(sport=self.tcp_port_in, dport=20), # UDP Ether(src=src_mac, dst=dst_mac) / IP(src=src_ip, dst=dst_ip) / UDP(sport=self.udp_port_in, dport=20), # ICMP Ether(src=src_mac, dst=dst_mac) / IP(src=src_ip, dst=dst_ip) / ICMP(id=self.icmp_id_in, type="echo-request"), ] def create_stream_encrypted(self, src_mac, dst_mac, src_ip, dst_ip, sa): return [ # TCP Ether(src=src_mac, dst=dst_mac) / sa.encrypt( IP(src=src_ip, dst=dst_ip) / TCP(dport=self.tcp_port_out, sport=20) ), # UDP Ether(src=src_mac, dst=dst_mac) / sa.encrypt( IP(src=src_ip, dst=dst_ip) / UDP(dport=self.udp_port_out, sport=20) ), # ICMP Ether(src=src_mac, dst=dst_mac) / sa.encrypt( IP(src=src_ip, dst=dst_ip) / ICMP(id=self.icmp_id_out, type="echo-request") ), ] def verify_capture_plain(self, capture): for packet in capture: try: self.assert_packet_checksums_valid(packet) self.assert_equal( packet[IP].src, self.tun_if.remote_ip4, "decrypted packet source address", ) self.assert_equal( packet[IP].dst, self.pg1.remote_ip4, "decrypted packet destination address", ) if packet.haslayer(TCP): self.assertFalse( packet.haslayer(UDP), "unexpected UDP header in decrypted packet", ) self.assert_equal( packet[TCP].dport, self.tcp_port_in, "decrypted packet TCP destination port", ) elif packet.haslayer(UDP): if packet[UDP].payload: self.assertFalse( packet[UDP][1].haslayer(UDP), "unexpected UDP header in decrypted packet", ) self.assert_equal( packet[UDP].dport, self.udp_port_in, "decrypted packet UDP destination port", ) else: self.assertFalse( packet.haslayer(UDP), "unexpected UDP header in decrypted packet", ) self.assert_equal( packet[ICMP].id, self.icmp_id_in, "decrypted packet ICMP ID" ) except Exception: self.logger.error(ppp("Unexpected or invalid plain packet:", packet)) raise def verify_capture_encrypted(self, capture, sa): for packet in capture: try: copy = packet.__class__(scapy.compat.raw(packet)) del copy[UDP].len copy = packet.__class__(scapy.compat.raw(copy)) self.assert_equal(packet[UDP].len, copy[UDP].len, "UDP header length") self.assert_packet_checksums_valid(packet) self.assertIn(ESP, packet[IP]) decrypt_pkt = sa.decrypt(packet[IP]) self.assert_packet_checksums_valid(decrypt_pkt) self.assert_equal( decrypt_pkt[IP].src, self.pg1.remote_ip4, "encrypted packet source address", ) self.assert_equal( decrypt_pkt[IP].dst, self.tun_if.remote_ip4, "encrypted packet destination address", ) except Exception: self.logger.error( ppp("Unexpected or invalid encrypted packet:", packet) ) raise def config_esp_tun(self, params): addr_type = params.addr_type scapy_tun_sa_id = params.scapy_tun_sa_id scapy_tun_spi = params.scapy_tun_spi vpp_tun_sa_id = params.vpp_tun_sa_id vpp_tun_spi = params.vpp_tun_spi auth_algo_vpp_id = params.auth_algo_vpp_id auth_key = params.auth_key crypt_algo_vpp_id = params.crypt_algo_vpp_id crypt_key = params.crypt_key addr_any = params.addr_any addr_bcast = params.addr_bcast flags = VppEnum.vl_api_ipsec_sad_flags_t.IPSEC_API_SAD_FLAG_UDP_ENCAP e = VppEnum.vl_api_ipsec_spd_action_t VppIpsecSA( self, scapy_tun_sa_id, scapy_tun_spi, auth_algo_vpp_id, auth_key, crypt_algo_vpp_id, crypt_key, self.vpp_esp_protocol, self.pg1.remote_addr[addr_type], self.tun_if.remote_addr[addr_type], flags=flags, ).add_vpp_config() VppIpsecSA( self, vpp_tun_sa_id, vpp_tun_spi, auth_algo_vpp_id, auth_key, crypt_algo_vpp_id, crypt_key, self.vpp_esp_protocol, self.tun_if.remote_addr[addr_type], self.pg1.remote_addr[addr_type], flags=flags, ).add_vpp_config() VppIpsecSpdEntry( self, self.tun_spd, scapy_tun_sa_id, addr_any, addr_bcast, addr_any, addr_bcast, socket.IPPROTO_ESP, ).add_vpp_config() VppIpsecSpdEntry( self, self.tun_spd, scapy_tun_sa_id, addr_any, addr_bcast, addr_any, addr_bcast, socket.IPPROTO_ESP, is_outbound=0, ).add_vpp_config() VppIpsecSpdEntry( self, self.tun_spd, scapy_tun_sa_id, addr_any, addr_bcast, addr_any, addr_bcast, socket.IPPROTO_UDP, remote_port_start=4500, remote_port_stop=4500, ).add_vpp_config() VppIpsecSpdEntry( self, self.tun_spd, scapy_tun_sa_id, addr_any, addr_bcast, addr_any, addr_bcast, socket.IPPROTO_UDP, remote_port_start=4500, remote_port_stop=4500, is_outbound=0, ).add_vpp_config() VppIpsecSpdEntry( self, self.tun_spd, vpp_tun_sa_id, self.tun_if.remote_addr[addr_type], self.tun_if.remote_addr[addr_type], self.pg1.remote_addr[addr_type], self.pg1.remote_addr[addr_type], socket.IPPROTO_RAW, priority=10, policy=e.IPSEC_API_SPD_ACTION_PROTECT, is_outbound=0, ).add_vpp_config() VppIpsecSpdEntry( self, self.tun_spd, scapy_tun_sa_id, self.pg1.remote_addr[addr_type], self.pg1.remote_addr[addr_type], self.tun_if.remote_addr[addr_type], self.tun_if.remote_addr[addr_type], socket.IPPROTO_RAW, policy=e.IPSEC_API_SPD_ACTION_PROTECT, priority=10, ).add_vpp_config() def test_ipsec_nat_tun(self): """IPSec/NAT tunnel test case""" p = self.ipv4_params scapy_tun_sa = SecurityAssociation( ESP, spi=p.scapy_tun_spi, crypt_algo=p.crypt_algo, crypt_key=p.crypt_key, auth_algo=p.auth_algo, auth_key=p.auth_key, tunnel_header=IP(src=self.pg1.remote_ip4, dst=self.tun_if.remote_ip4), nat_t_header=UDP(sport=4500, dport=4500), ) # in2out - from private network to public pkts = self.create_stream_plain( self.pg1.remote_mac, self.pg1.local_mac, self.pg1.remote_ip4, self.tun_if.remote_ip4, ) self.pg1.add_stream(pkts) self.pg_enable_capture(self.pg_interfaces) self.pg_start() capture = self.tun_if.get_capture(len(pkts)) self.verify_capture_encrypted(capture, scapy_tun_sa) vpp_tun_sa = SecurityAssociation( ESP, spi=p.vpp_tun_spi, crypt_algo=p.crypt_algo, crypt_key=p.crypt_key, auth_algo=p.auth_algo, auth_key=p.auth_key, tunnel_header=IP(src=self.tun_if.remote_ip4, dst=self.pg1.remote_ip4), nat_t_header=UDP(sport=4500, dport=4500), ) # out2in - from public network to private pkts = self.create_stream_encrypted( self.tun_if.remote_mac, self.tun_if.local_mac, self.tun_if.remote_ip4, self.pg1.remote_ip4, vpp_tun_sa, ) self.logger.info(ppc("Sending packets:", pkts)) self.tun_if.add_stream(pkts) self.pg_enable_capture(self.pg_interfaces) self.pg_start() capture = self.pg1.get_capture(len(pkts)) self.verify_capture_plain(capture)