#!/usr/bin/env python
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],
0, 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],
0, 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)
