import socket import unittest from util import ppp from asfframework import VppTestRunner from template_ipsec import IpsecDefaultTemplate """ When an IPSec SPD is configured on an interface, any inbound packets not matching inbound policies, or outbound packets not matching outbound policies, must be dropped by default as per RFC4301. This test uses simple IPv4 forwarding on interfaces with IPSec enabled to check if packets with no matching rules are dropped by default. The basic setup is a single SPD bound to two interfaces, pg0 and pg1. ┌────┐ ┌────┐ │SPD1│ │SPD1│ ├────┤ ─────> ├────┤ │PG0 │ │PG1 │ └────┘ └────┘ First, both inbound and outbound BYPASS policies are configured allowing traffic to pass from pg0 -> pg1. Packets are captured and verified at pg1. Then either the inbound or outbound policies are removed and we verify packets are dropped as expected. """ class IPSecInboundDefaultDrop(IpsecDefaultTemplate): """IPSec: inbound packets drop by default with no matching rule""" def test_ipsec_inbound_default_drop(self): # configure two interfaces and bind the same SPD to both self.create_interfaces(2) self.spd_create_and_intf_add(1, self.pg_interfaces) pkt_count = 5 # catch-all inbound BYPASS policy, all interfaces inbound_policy = self.spd_add_rem_policy( 1, None, None, socket.IPPROTO_UDP, is_out=0, priority=10, policy_type="bypass", all_ips=True, ) # outbound BYPASS policy allowing traffic from pg0->pg1 outbound_policy = self.spd_add_rem_policy( 1, self.pg0, self.pg1, socket.IPPROTO_UDP, is_out=1, priority=10, policy_type="bypass", ) # create a packet stream pg0->pg1 + add to pg0 packets0 = self.create_stream(self.pg0, self.pg1, pkt_count) self.pg0.add_stream(packets0) # with inbound BYPASS rule at pg0, we expect to see forwarded # packets on pg1 self.pg_interfaces[1].enable_capture() self.pg_start() cap1 = self.pg1.get_capture() for packet in cap1: try: self.logger.debug(ppp("SPD - Got packet:", packet)) except Exception: self.logger.error(ppp("Unexpected or invalid packet:", packet)) raise self.logger.debug("SPD: Num packets: %s", len(cap1.res)) # verify captures on pg1 self.verify_capture(self.pg0, self.pg1, cap1) # verify policies matched correct number of times self.verify_policy_match(pkt_count, inbound_policy) self.verify_policy_match(pkt_count, outbound_policy) # remove inbound catch-all BYPASS rule, traffic should now be dropped self.spd_add_rem_policy( # inbound, all interfaces 1, None, None, socket.IPPROTO_UDP, is_out=0, priority=10, policy_type="bypass", all_ips=True, remove=True, ) # create another packet stream pg0->pg1 + add to pg0 packets1 = self.create_stream(self.pg0, self.pg1, pkt_count) self.pg0.add_stream(packets1) self.pg_interfaces[1].enable_capture() self.pg_start() # confirm traffic has now been dropped self.pg1.assert_nothing_captured( remark="inbound pkts with no matching" "rules NOT dropped by default" ) # both policies should not have matched any further packets # since we've dropped at input stage self.verify_policy_match(pkt_count, outbound_policy) self.verify_policy_match(pkt_count, inbound_policy) class IPSecOutboundDefaultDrop(IpsecDefaultTemplate): """IPSec: outbound packets drop by default with no matching rule""" def test_ipsec_inbound_default_drop(self): # configure two interfaces and bind the same SPD to both self.create_interfaces(2) self.spd_create_and_intf_add(1, self.pg_interfaces) pkt_count = 5 # catch-all inbound BYPASS policy, all interfaces inbound_policy = self.spd_add_rem_policy( 1, None, None, socket.IPPROTO_UDP, is_out=0, priority=10, policy_type="bypass", all_ips=True, ) # outbound BYPASS policy allowing traffic from pg0->pg1 outbound_policy = self.spd_add_rem_policy( 1, self.pg0, self.pg1, socket.IPPROTO_UDP, is_out=1, priority=10, policy_type="bypass", ) # create a packet stream pg0->pg1 + add to pg0 packets0 = self.create_stream(self.pg0, self.pg1, pkt_count) self.pg0.add_stream(packets0) # with outbound BYPASS rule allowing pg0->pg1, we expect to see # forwarded packets on pg1 self.pg_interfaces[1].enable_capture() self.pg_start() cap1 = self.pg1.get_capture() for packet in cap1: try: self.logger.debug(ppp("SPD - Got packet:", packet)) except Exception: self.logger.error(ppp("Unexpected or invalid packet:", packet)) raise self.logger.debug("SPD: Num packets: %s", len(cap1.res)) # verify captures on pg1 self.verify_capture(self.pg0, self.pg1, cap1) # verify policies matched correct number of times self.verify_policy_match(pkt_count, inbound_policy) self.verify_policy_match(pkt_count, outbound_policy) # remove outbound rule self.spd_add_rem_policy( 1, self.pg0, self.pg1, socket.IPPROTO_UDP, is_out=1, priority=10, policy_type="bypass", remove=True, ) # create another packet stream pg0->pg1 + add to pg0 packets1 = self.create_stream(self.pg0, self.pg1, pkt_count) self.pg0.add_stream(packets1) self.pg_interfaces[1].enable_capture() self.pg_start() # confirm traffic was dropped and not forwarded self.pg1.assert_nothing_captured( remark="outbound pkts with no matching rules NOT dropped " "by default" ) # inbound rule should have matched twice the # of pkts now self.verify_policy_match(pkt_count * 2, inbound_policy) # as dropped at outbound, outbound policy is the same self.verify_policy_match(pkt_count, outbound_policy) if __name__ == "__main__": unittest.main(testRunner=VppTestRunner)