import unittest
import socket
import struct

from scapy.layers.inet import IP, ICMP, TCP, UDP
from scapy.layers.ipsec import SecurityAssociation, ESP
from scapy.layers.l2 import Ether, Raw
from scapy.layers.inet6 import IPv6, ICMPv6EchoRequest

from framework import VppTestCase, VppTestRunner
from util import ppp, reassemble4
from vpp_papi import VppEnum


class IPsecIPv4Params(object):

    addr_type = socket.AF_INET
    addr_any = "0.0.0.0"
    addr_bcast = "255.255.255.255"
    addr_len = 32
    is_ipv6 = 0

    def __init__(self):
        self.remote_tun_if_host = '1.1.1.1'
        self.remote_tun_if_host6 = '1111::1'

        self.scapy_tun_sa_id = 10
        self.scapy_tun_spi = 1001
        self.vpp_tun_sa_id = 20
        self.vpp_tun_spi = 1000

        self.scapy_tra_sa_id = 30
        self.scapy_tra_spi = 2001
        self.vpp_tra_sa_id = 40
        self.vpp_tra_spi = 2000

        self.auth_algo_vpp_id = (VppEnum.vl_api_ipsec_integ_alg_t.
                                 IPSEC_API_INTEG_ALG_SHA1_96)
        self.auth_algo = 'HMAC-SHA1-96'  # scapy name
        self.auth_key = 'C91KUR9GYMm5GfkEvNjX'

        self.crypt_algo_vpp_id = (VppEnum.vl_api_ipsec_crypto_alg_t.
                                  IPSEC_API_CRYPTO_ALG_AES_CBC_128)
        self.crypt_algo = 'AES-CBC'  # scapy name
        self.crypt_key = 'JPjyOWBeVEQiMe7h'
        self.salt = 0
        self.flags = 0
        self.nat_header = None


class IPsecIPv6Params(object):

    addr_type = socket.AF_INET6
    addr_any = "0::0"
    addr_bcast = "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff"
    addr_len = 128
    is_ipv6 = 1

    def __init__(self):
        self.remote_tun_if_host = '1111:1111:1111:1111:1111:1111:1111:1111'
        self.remote_tun_if_host4 = '1.1.1.1'

        self.scapy_tun_sa_id = 50
        self.scapy_tun_spi = 3001
        self.vpp_tun_sa_id = 60
        self.vpp_tun_spi = 3000

        self.scapy_tra_sa_id = 70
        self.scapy_tra_spi = 4001
        self.vpp_tra_sa_id = 80
        self.vpp_tra_spi = 4000

        self.auth_algo_vpp_id = (VppEnum.vl_api_ipsec_integ_alg_t.
                                 IPSEC_API_INTEG_ALG_SHA1_96)
        self.auth_algo = 'HMAC-SHA1-96'  # scapy name
        self.auth_key = 'C91KUR9GYMm5GfkEvNjX'

        self.crypt_algo_vpp_id = (VppEnum.vl_api_ipsec_crypto_alg_t.
                                  IPSEC_API_CRYPTO_ALG_AES_CBC_128)
        self.crypt_algo = 'AES-CBC'  # scapy name
        self.crypt_key = 'JPjyOWBeVEQiMe7h'
        self.salt = 0
        self.flags = 0
        self.nat_header = None


def config_tun_params(p, encryption_type, tun_if):
    ip_class_by_addr_type = {socket.AF_INET: IP, socket.AF_INET6: IPv6}
    use_esn = bool(p.flags & (VppEnum.vl_api_ipsec_sad_flags_t.
                              IPSEC_API_SAD_FLAG_USE_ESN))
    if p.crypt_algo == "AES-GCM":
        crypt_key = p.crypt_key + struct.pack("!I", p.salt)
    else:
        crypt_key = p.crypt_key
    p.scapy_tun_sa = SecurityAssociation(
        encryption_type, spi=p.vpp_tun_spi,
        crypt_algo=p.crypt_algo,
        crypt_key=crypt_key,
        auth_algo=p.auth_algo, auth_key=p.auth_key,
        tunnel_header=ip_class_by_addr_type[p.addr_type](
            src=tun_if.remote_addr[p.addr_type],
            dst=tun_if.local_addr[p.addr_type]),
        nat_t_header=p.nat_header,
        use_esn=use_esn)
    p.vpp_tun_sa = SecurityAssociation(
        encryption_type, spi=p.scapy_tun_spi,
        crypt_algo=p.crypt_algo,
        crypt_key=crypt_key,
        auth_algo=p.auth_algo, auth_key=p.auth_key,
        tunnel_header=ip_class_by_addr_type[p.addr_type](
            dst=tun_if.remote_addr[p.addr_type],
            src=tun_if.local_addr[p.addr_type]),
        nat_t_header=p.nat_header,
        use_esn=use_esn)


def config_tra_params(p, encryption_type):
    use_esn = bool(p.flags & (VppEnum.vl_api_ipsec_sad_flags_t.
                              IPSEC_API_SAD_FLAG_USE_ESN))
    if p.crypt_algo == "AES-GCM":
        crypt_key = p.crypt_key + struct.pack("!I", p.salt)
    else:
        crypt_key = p.crypt_key
    p.scapy_tra_sa = SecurityAssociation(
        encryption_type,
        spi=p.vpp_tra_spi,
        crypt_algo=p.crypt_algo,
        crypt_key=crypt_key,
        auth_algo=p.auth_algo,
        auth_key=p.auth_key,
        nat_t_header=p.nat_header,
        use_esn=use_esn)
    p.vpp_tra_sa = SecurityAssociation(
        encryption_type,
        spi=p.scapy_tra_spi,
        crypt_algo=p.crypt_algo,
        crypt_key=crypt_key,
        auth_algo=p.auth_algo,
        auth_key=p.auth_key,
        nat_t_header=p.nat_header,
        use_esn=use_esn)


class TemplateIpsec(VppTestCase):
    """
    TRANSPORT MODE:

     ------   encrypt   ---
    |tra_if| <-------> |VPP|
     ------   decrypt   ---

    TUNNEL MODE:

     ------   encrypt   ---   plain   ---
    |tun_if| <-------  |VPP| <------ |pg1|
     ------             ---           ---

     ------   decrypt   ---   plain   ---
    |tun_if| ------->  |VPP| ------> |pg1|
     ------             ---           ---
    """
    tun_spd_id = 1
    tra_spd_id = 2

    def ipsec_select_backend(self):
        """ empty method to be overloaded when necessary """
        pass

    @classmethod
    def setUpClass(cls):
        super(TemplateIpsec, cls).setUpClass()

    @classmethod
    def tearDownClass(cls):
        super(TemplateIpsec, cls).tearDownClass()

    def setup_params(self):
        self.ipv4_params = IPsecIPv4Params()
        self.ipv6_params = IPsecIPv6Params()
        self.params = {self.ipv4_params.addr_type: self.ipv4_params,
                       self.ipv6_params.addr_type: self.ipv6_params}

    def config_interfaces(self):
        self.create_pg_interfaces(range(3))
        self.interfaces = list(self.pg_interfaces)
        for i in self.interfaces:
            i.admin_up()
            i.config_ip4()
            i.resolve_arp()
            i.config_ip6()
            i.resolve_ndp()

    def setUp(self):
        super(TemplateIpsec, self).setUp()

        self.setup_params()

        self.vpp_esp_protocol = (VppEnum.vl_api_ipsec_proto_t.
                                 IPSEC_API_PROTO_ESP)
        self.vpp_ah_protocol = (VppEnum.vl_api_ipsec_proto_t.
                                IPSEC_API_PROTO_AH)

        self.config_interfaces()

        self.ipsec_select_backend()

    def unconfig_interfaces(self):
        for i in self.interfaces:
            i.admin_down()
            i.unconfig_ip4()
            i.unconfig_ip6()

    def tearDown(self):
        super(TemplateIpsec, self).tearDown()

        self.unconfig_interfaces()

    def show_commands_at_teardown(self):
        self.logger.info(self.vapi.cli("show hardware"))

    def gen_encrypt_pkts(self, sa, sw_intf, src, dst, count=1,
                         payload_size=54):
        return [Ether(src=sw_intf.remote_mac, dst=sw_intf.local_mac) /
                sa.encrypt(IP(src=src, dst=dst) /
                           ICMP() / Raw('X' * payload_size))
                for i in range(count)]

    def gen_encrypt_pkts6(self, sa, sw_intf, src, dst, count=1,
                          payload_size=54):
        return [Ether(src=sw_intf.remote_mac, dst=sw_intf.local_mac) /
                sa.encrypt(IPv6(src=src, dst=dst) /
                           ICMPv6EchoRequest(id=0, seq=1,
                                             data='X' * payload_size))
                for i in range(count)]

    def gen_pkts(self, sw_intf, src, dst, count=1, payload_size=54):
        return [Ether(src=sw_intf.remote_mac, dst=sw_intf.local_mac) /
                IP(src=src, dst=dst) / ICMP() / Raw('X' * payload_size)
                for i in range(count)]

    def gen_pkts6(self, sw_intf, src, dst, count=1, payload_size=54):
        return [Ether(src=sw_intf.remote_mac, dst=sw_intf.local_mac) /
                IPv6(src=src, dst=dst) /
                ICMPv6EchoRequest(id=0, seq=1, data='X' * payload_size)
                for i in range(count)]


class IpsecTcp(object):
    def verify_tcp_checksum(self):
        self.vapi.cli("test http server")
        p = self.params[socket.AF_INET]
        config_tun_params(p, self.encryption_type, self.tun_if)
        send = (Ether(src=self.tun_if.remote_mac, dst=self.tun_if.local_mac) /
                p.scapy_tun_sa.encrypt(IP(src=p.remote_tun_if_host,
                                          dst=self.tun_if.local_ip4) /
                                       TCP(flags='S', dport=80)))
        self.logger.debug(ppp("Sending packet:", send))
        recv = self.send_and_expect(self.tun_if, [send], self.tun_if)
        recv = recv[0]
        decrypted = p.vpp_tun_sa.decrypt(recv[IP])
        self.assert_packet_checksums_valid(decrypted)


class IpsecTcpTests(IpsecTcp):
    def test_tcp_checksum(self):
        """ verify checksum correctness for vpp generated packets """
        self.verify_tcp_checksum()


class IpsecTra4(object):
    """ verify methods for Transport v4 """
    def verify_tra_anti_replay(self, count=1):
        p = self.params[socket.AF_INET]
        use_esn = p.vpp_tra_sa.use_esn

        # fire in a packet with seq number 1
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                         dst=self.tra_if.local_ip4) /
                                      ICMP(),
                                      seq_num=1))
        recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if)

        # now move the window over to 235
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                         dst=self.tra_if.local_ip4) /
                                      ICMP(),
                                      seq_num=235))
        recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if)

        # replayed packets are dropped
        self.send_and_assert_no_replies(self.tra_if, pkt * 3)
        self.assert_error_counter_equal(
            '/err/%s/SA replayed packet' % self.tra4_decrypt_node_name, 3)

        # the window size is 64 packets
        # in window are still accepted
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                         dst=self.tra_if.local_ip4) /
                                      ICMP(),
                                      seq_num=172))
        recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if)

        # a packet that does not decrypt does not move the window forward
        bogus_sa = SecurityAssociation(self.encryption_type,
                                       p.vpp_tra_spi,
                                       crypt_algo=p.crypt_algo,
                                       crypt_key=p.crypt_key[::-1],
                                       auth_algo=p.auth_algo,
                                       auth_key=p.auth_key[::-1])
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               bogus_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                   dst=self.tra_if.local_ip4) /
                                ICMP(),
                                seq_num=350))
        self.send_and_assert_no_replies(self.tra_if, pkt * 17)

        self.assert_error_counter_equal(
            '/err/%s/Integrity check failed' % self.tra4_decrypt_node_name, 17)

        # a malformed 'runt' packet
        #  created by a mis-constructed SA
        if (ESP == self.encryption_type):
            bogus_sa = SecurityAssociation(self.encryption_type,
                                           p.vpp_tra_spi)
            pkt = (Ether(src=self.tra_if.remote_mac,
                         dst=self.tra_if.local_mac) /
                   bogus_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                       dst=self.tra_if.local_ip4) /
                                    ICMP(),
                                    seq_num=350))
            self.send_and_assert_no_replies(self.tra_if, pkt * 17)

            self.assert_error_counter_equal(
                '/err/%s/undersized packet' % self.tra4_decrypt_node_name, 17)

        # which we can determine since this packet is still in the window
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                         dst=self.tra_if.local_ip4) /
                                      ICMP(),
                                      seq_num=234))
        self.send_and_expect(self.tra_if, [pkt], self.tra_if)

        # out of window are dropped
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                         dst=self.tra_if.local_ip4) /
                                      ICMP(),
                                      seq_num=17))
        self.send_and_assert_no_replies(self.tra_if, pkt * 17)

        if use_esn:
            # an out of window error with ESN looks like a high sequence
            # wrap. but since it isn't then the verify will fail.
            self.assert_error_counter_equal(
                '/err/%s/Integrity check failed' %
                self.tra4_decrypt_node_name, 34)

        else:
            self.assert_error_counter_equal(
                '/err/%s/SA replayed packet' %
                self.tra4_decrypt_node_name, 20)

        # valid packet moves the window over to 236
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                         dst=self.tra_if.local_ip4) /
                                      ICMP(),
                                      seq_num=236))
        rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
        decrypted = p.vpp_tra_sa.decrypt(rx[0][IP])

        # move VPP's SA to just before the seq-number wrap
        self.vapi.cli("test ipsec sa %d seq 0xffffffff" % p.scapy_tra_sa_id)

        # then fire in a packet that VPP should drop because it causes the
        # seq number to wrap  unless we're using extended.
        pkt = (Ether(src=self.tra_if.remote_mac,
                     dst=self.tra_if.local_mac) /
               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                         dst=self.tra_if.local_ip4) /
                                      ICMP(),
                                      seq_num=237))

        if use_esn:
            rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
            # in order to decrpyt the high order number needs to wrap
            p.vpp_tra_sa.seq_num = 0x100000000
            decrypted = p.vpp_tra_sa.decrypt(rx[0][IP])

            # send packets with high bits set
            p.scapy_tra_sa.seq_num = 0x100000005
            pkt = (Ether(src=self.tra_if.remote_mac,
                         dst=self.tra_if.local_mac) /
                   p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                             dst=self.tra_if.local_ip4) /
                                          ICMP(),
                                          seq_num=0x100000005))
            rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
            # in order to decrpyt the high order number needs to wrap
            decrypted = p.vpp_tra_sa.decrypt(rx[0][IP])
        else:
            self.send_and_assert_no_replies(self.tra_if, [pkt])
            self.assert_error_counter_equal(
                '/err/%s/sequence number cycled' %
                self.tra4_encrypt_node_name, 1)

        # move the security-associations seq number on to the last we used
        self.vapi.cli("test ipsec sa %d seq 0x15f" % p.scapy_tra_sa_id)
        p.scapy_tra_sa.seq_num = 351
        p.vpp_tra_sa.seq_num = 351

    def verify_tra_basic4(self, count=1):
        """ ipsec v4 transport basic test """
        self.vapi.cli("clear errors")
        try:
            p = self.params[socket.AF_INET]
            send_pkts = self.gen_encrypt_pkts(p.scapy_tra_sa, self.tra_if,
                                              src=self.tra_if.remote_ip4,
                                              dst=self.tra_if.local_ip4,
                                              count=count)
            recv_pkts = self.send_and_expect(self.tra_if, send_pkts,
                                             self.tra_if)
            for rx in recv_pkts:
                self.assertEqual(len(rx) - len(Ether()), rx[IP].len)
                self.assert_packet_checksums_valid(rx)
                try:
                    decrypted = p.vpp_tra_sa.decrypt(rx[IP])
                    self.assert_packet_checksums_valid(decrypted)
                except:
                    self.logger.debug(ppp("Unexpected packet:", rx))
                    raise
        finally:
            self.logger.info(self.vapi.ppcli("show error"))
            self.logger.info(self.vapi.ppcli("show ipsec all"))

        pkts = p.tra_sa_in.get_stats()['packets']
        self.assertEqual(pkts, count,
                         "incorrect SA in counts: expected %d != %d" %
                         (count, pkts))
        pkts = p.tra_sa_out.get_stats()['packets']
        self.assertEqual(pkts, count,
                         "incorrect SA out counts: expected %d != %d" %
                         (count, pkts))

        self.assert_packet_counter_equal(self.tra4_encrypt_node_name, count)
        self.assert_packet_counter_equal(self.tra4_decrypt_node_name, count)


class IpsecTra4Tests(IpsecTra4):
    """ UT test methods for Transport v4 """
    def test_tra_anti_replay(self):
        """ ipsec v4 transport anti-reply test """
        self.verify_tra_anti_replay(count=1)

    def test_tra_basic(self, count=1):
        """ ipsec v4 transport basic test """
        self.verify_tra_basic4(count=1)

    def test_tra_burst(self):
        """ ipsec v4 transport burst test """
        self.verify_tra_basic4(count=257)


class IpsecTra6(object):
    """ verify methods for Transport v6 """
    def verify_tra_basic6(self, count=1):
        self.vapi.cli("clear errors")
        try:
            p = self.params[socket.AF_INET6]
            send_pkts = self.gen_encrypt_pkts6(p.scapy_tra_sa, self.tra_if,
                                               src=self.tra_if.remote_ip6,
                                               dst=self.tra_if.local_ip6,
                                               count=count)
            recv_pkts = self.send_and_expect(self.tra_if, send_pkts,
                                             self.tra_if)
            for rx in recv_pkts:
                self.assertEqual(len(rx) - len(Ether()) - len(IPv6()),
                                 rx[IPv6].plen)
                try:
                    decrypted = p.vpp_tra_sa.decrypt(rx[IPv6])
                    self.assert_packet_checksums_valid(decrypted)
                except:
                    self.logger.debug(ppp("Unexpected packet:", rx))
                    raise
        finally:
            self.logger.info(self.vapi.ppcli("show error"))
            self.logger.info(self.vapi.ppcli("show ipsec all"))

        pkts = p.tra_sa_in.get_stats()['packets']
        self.assertEqual(pkts, count,
                         "incorrect SA in counts: expected %d != %d" %
                         (count, pkts))
        pkts = p.tra_sa_out.get_stats()['packets']
        self.assertEqual(pkts, count,
                         "incorrect SA out counts: expected %d != %d" %
                         (count, pkts))
        self.assert_packet_counter_equal(self.tra6_encrypt_node_name, count)
        self.assert_packet_counter_equal(self.tra6_decrypt_node_name, count)


class IpsecTra6Tests(IpsecTra6):
    """ UT test methods for Transport v6 """
    def test_tra_basic6(self):
        """ ipsec v6 transport basic test """
        self.verify_tra_basic6(count=1)

    def test_tra_burst6(self):
        """ ipsec v6 transport burst test """
        self.verify_tra_basic6(count=257)


class IpsecTra46Tests(IpsecTra4Tests, IpsecTra6Tests):
    """ UT test methods for Transport v6 and v4"""
    pass


class IpsecTun4(object):
    """ verify methods for Tunnel v4 """
    def verify_counters4(self, p, count, n_frags=None):
        if not n_frags:
            n_frags = count
        if (hasattr(p, "spd_policy_in_any")):
            pkts = p.spd_policy_in_any.get_stats()['packets']
            self.assertEqual(pkts, count,
                             "incorrect SPD any policy: expected %d != %d" %
                             (count, pkts))

        if (hasattr(p, "tun_sa_in")):
            pkts = p.tun_sa_in.get_stats()['packets']
            self.assertEqual(pkts, count,
                             "incorrect SA in counts: expected %d != %d" %
                             (count, pkts))
            pkts = p.tun_sa_out.get_stats()['packets']
            self.assertEqual(pkts, count,
                             "incorrect SA out counts: expected %d != %d" %
                             (count, pkts))

        self.assert_packet_counter_equal(self.tun4_encrypt_node_name, n_frags)
        self.assert_packet_counter_equal(self.tun4_decrypt_node_name, count)

    def verify_decrypted(self, p, rxs):
        for rx in rxs:
            self.assert_equal(rx[IP].src, p.remote_tun_if_host)
            self.assert_equal(rx[IP].dst, self.pg1.remote_ip4)
            self.assert_packet_checksums_valid(rx)

    def verify_encrypted(self, p, sa, rxs):
        decrypt_pkts = []
        for rx in rxs:
            if p.nat_header:
                self.assertEqual(rx[UDP].dport, 4500)
            self.assert_packet_checksums_valid(rx)
            self.assertEqual(len(rx) - len(Ether()), rx[IP].len)
            try:
                decrypt_pkt = p.vpp_tun_sa.decrypt(rx[IP])
                if not decrypt_pkt.haslayer(IP):
                    decrypt_pkt = IP(decrypt_pkt[Raw].load)
                decrypt_pkts.append(decrypt_pkt)
                self.assert_equal(decrypt_pkt.src, self.pg1.remote_ip4)
                self.assert_equal(decrypt_pkt.dst, p.remote_tun_if_host)
            except:
                self.logger.debug(ppp("Unexpected packet:", rx))
                try:
                    self.logger.debug(ppp("Decrypted packet:", decrypt_pkt))
                except:
                    pass
                raise
        pkts = reassemble4(decrypt_pkts)
        for pkt in pkts:
            self.assert_packet_checksums_valid(pkt)

    def verify_tun_44(self, p, count=1, payload_size=64, n_rx=None):
        self.vapi.cli("clear errors")
        if not n_rx:
            n_rx = count
        try:
            config_tun_params(p, self.encryption_type, self.tun_if)
            send_pkts = self.gen_encrypt_pkts(p.scapy_tun_sa, self.tun_if,
                                              src=p.remote_tun_if_host,
                                              dst=self.pg1.remote_ip4,
                                              count=count)
            recv_pkts = self.send_and_expect(self.tun_if, send_pkts, self.pg1)
            self.verify_decrypted(p, recv_pkts)

            send_pkts = self.gen_pkts(self.pg1, src=self.pg1.remote_ip4,
                                      dst=p.remote_tun_if_host, count=count,
                                      payload_size=payload_size)
            recv_pkts = self.send_and_expect(self.pg1, send_pkts,
                                             self.tun_if, n_rx)
            self.verify_encrypted(p, p.vpp_tun_sa, recv_pkts)

        finally:
            self.logger.info(self.vapi.ppcli("show error"))
            self.logger.info(self.vapi.ppcli("show ipsec all"))

        self.verify_counters4(p, count, n_rx)

    def verify_tun_64(self, p, count=1):
        self.vapi.cli("clear errors")
        try:
            config_tun_params(p, self.encryption_type, self.tun_if)
            send_pkts = self.gen_encrypt_pkts6(p.scapy_tun_sa, self.tun_if,
                                               src=p.remote_tun_if_host6,
                                               dst=self.pg1.remote_ip6,
                                               count=count)
            recv_pkts = self.send_and_expect(self.tun_if, send_pkts, self.pg1)
            for recv_pkt in recv_pkts:
                self.assert_equal(recv_pkt[IPv6].src, p.remote_tun_if_host6)
                self.assert_equal(recv_pkt[IPv6].dst, self.pg1.remote_ip6)
                self.assert_packet_checksums_valid(recv_pkt)
            send_pkts = self.gen_pkts6(self.pg1, src=self.pg1.remote_ip6,
                                       dst=p.remote_tun_if_host6, count=count)
            recv_pkts = self.send_and_expect(self.pg1, send_pkts, self.tun_if)
            for recv_pkt in recv_pkts:
                try:
                    decrypt_pkt = p.vpp_tun_sa.decrypt(recv_pkt[IP])
                    if not decrypt_pkt.haslayer(IPv6):
                        decrypt_pkt = IPv6(decrypt_pkt[Raw].load)
                    self.assert_equal(decrypt_pkt.src, self.pg1.remote_ip6)
                    self.assert_equal(decrypt_pkt.dst, p.remote_tun_if_host6)
                    self.assert_packet_checksums_valid(decrypt_pkt)
                except:
                    self.logger.error(ppp("Unexpected packet:", recv_pkt))
                    try:
                        self.logger.debug(
                            ppp("Decrypted packet:", decrypt_pkt))
                    except:
                        pass
                    raise
        finally:
            self.logger.info(self.vapi.ppcli("show error"))
            self.logger.info(self.vapi.ppcli("show ipsec all"))

        self.verify_counters4(p, count)

    def verify_keepalive(self, p):
        pkt = (Ether(src=self.tun_if.remote_mac, dst=self.tun_if.local_mac) /
               IP(src=p.remote_tun_if_host, dst=self.tun_if.local_ip4) /
               UDP(sport=333, dport=4500) /
               Raw(0xff))
        self.send_and_assert_no_replies(self.tun_if, pkt*31)
        self.assert_error_counter_equal(
            '/err/%s/NAT Keepalive' % self.tun4_input_node, 31)

        pkt = (Ether(src=self.tun_if.remote_mac, dst=self.tun_if.local_mac) /
               IP(src=p.remote_tun_if_host, dst=self.tun_if.local_ip4) /
               UDP(sport=333, dport=4500) /
               Raw(0xfe))
        self.send_and_assert_no_replies(self.tun_if, pkt*31)
        self.assert_error_counter_equal(
            '/err/%s/Too Short' % self.tun4_input_node, 31)


class IpsecTun4Tests(IpsecTun4):
    """ UT test methods for Tunnel v4 """
    def test_tun_basic44(self):
        """ ipsec 4o4 tunnel basic test """
        self.verify_tun_44(self.params[socket.AF_INET], count=1)

    def test_tun_burst44(self):
        """ ipsec 4o4 tunnel burst test """
        self.verify_tun_44(self.params[socket.AF_INET], count=257)


class IpsecTun6(object):
    """ verify methods for Tunnel v6 """
    def verify_counters6(self, p_in, p_out, count):
        if (hasattr(p_in, "tun_sa_in")):
            pkts = p_in.tun_sa_in.get_stats()['packets']
            self.assertEqual(pkts, count,
                             "incorrect SA in counts: expected %d != %d" %
                             (count, pkts))
        if (hasattr(p_out, "tun_sa_out")):
            pkts = p_out.tun_sa_out.get_stats()['packets']
            self.assertEqual(pkts, count,
                             "incorrect SA out counts: expected %d != %d" %
                             (count, pkts))
        self.assert_packet_counter_equal(self.tun6_encrypt_node_name, count)
        self.assert_packet_counter_equal(self.tun6_decrypt_node_name, count)

    def verify_decrypted6(self, p, rxs):
        for rx in rxs:
            self.assert_equal(rx[IPv6].src, p.remote_tun_if_host)
            self.assert_equal(rx[IPv6].dst, self.pg1.remote_ip6)
            self.assert_packet_checksums_valid(rx)

    def verify_encrypted6(self, p, sa, rxs):
        for rx in rxs:
            self.assert_packet_checksums_valid(rx)
            self.assertEqual(len(rx) - len(Ether()) - len(IPv6()),
                             rx[IPv6].plen)
            try:
                decrypt_pkt = p.vpp_tun_sa.decrypt(rx[IPv6])
                if not decrypt_pkt.haslayer(IPv6):
                    decrypt_pkt = IPv6(decrypt_pkt[Raw].load)
                self.assert_packet_checksums_valid(decrypt_pkt)
                self.assert_equal(decrypt_pkt.src, self.pg1.remote_ip6)
                self.assert_equal(decrypt_pkt.dst, p.remote_tun_if_host)
            except:
                self.logger.debug(ppp("Unexpected packet:", rx))
                try:
                    self.logger.debug(ppp("Decrypted packet:", decrypt_pkt))
                except:
                    pass
                raise

    def verify_drop_tun_66(self, p_in, count=1, payload_size=64):
        self.vapi.cli("clear errors")
        self.vapi.cli("clear ipsec sa")

        config_tun_params(p_in, self.encryption_type, self.tun_if)
        send_pkts = self.gen_encrypt_pkts6(p_in.scapy_tun_sa, self.tun_if,
                                           src=p_in.remote_tun_if_host,
                                           dst=self.pg1.remote_ip6,
                                           count=count)
        self.send_and_assert_no_replies(self.tun_if, send_pkts)
        self.logger.info(self.vapi.cli("sh punt stats"))

    def verify_tun_66(self, p_in, p_out=None, count=1, payload_size=64):
        self.vapi.cli("clear errors")
        self.vapi.cli("clear ipsec sa")
        if not p_out:
            p_out = p_in
        try:
            config_tun_params(p_in, self.encryption_type, self.tun_if)
            config_tun_params(p_out, self.encryption_type, self.tun_if)
            send_pkts = self.gen_encrypt_pkts6(p_in.scapy_tun_sa, self.tun_if,
                                               src=p_in.remote_tun_if_host,
                                               dst=self.pg1.remote_ip6,
                                               count=count)
            recv_pkts = self.send_and_expect(self.tun_if, send_pkts, self.pg1)
            self.verify_decrypted6(p_in, recv_pkts)

            send_pkts = self.gen_pkts6(self.pg1, src=self.pg1.remote_ip6,
                                       dst=p_out.remote_tun_if_host,
                                       count=count,
                                       payload_size=payload_size)
            recv_pkts = self.send_and_expect(self.pg1, send_pkts,
                                             self.tun_if)
            self.verify_encrypted6(p_out, p_out.vpp_tun_sa, recv_pkts)

        finally:
            self.logger.info(self.vapi.ppcli("show error"))
            self.logger.info(self.vapi.ppcli("show ipsec all"))
        self.verify_counters6(p_in, p_out, count)

    def verify_tun_46(self, p, count=1):
        """ ipsec 4o6 tunnel basic test """
        self.vapi.cli("clear errors")
        try:
            config_tun_params(p, self.encryption_type, self.tun_if)
            send_pkts = self.gen_encrypt_pkts(p.scapy_tun_sa, self.tun_if,
                                              src=p.remote_tun_if_host4,
                                              dst=self.pg1.remote_ip4,
                                              count=count)
            recv_pkts = self.send_and_expect(self.tun_if, send_pkts, self.pg1)
            for recv_pkt in recv_pkts:
                self.assert_equal(recv_pkt[IP].src, p.remote_tun_if_host4)
                self.assert_equal(recv_pkt[IP].dst, self.pg1.remote_ip4)
                self.assert_packet_checksums_valid(recv_pkt)
            send_pkts = self.gen_pkts(self.pg1, src=self.pg1.remote_ip4,
                                      dst=p.remote_tun_if_host4,
                                      count=count)
            recv_pkts = self.send_and_expect(self.pg1, send_pkts, self.tun_if)
            for recv_pkt in recv_pkts:
                try:
                    decrypt_pkt = p.vpp_tun_sa.decrypt(recv_pkt[IPv6])
                    if not decrypt_pkt.haslayer(IP):
                        decrypt_pkt = IP(decrypt_pkt[Raw].load)
                    self.assert_equal(decrypt_pkt.src, self.pg1.remote_ip4)
                    self.assert_equal(decrypt_pkt.dst, p.remote_tun_if_host4)
                    self.assert_packet_checksums_valid(decrypt_pkt)
                except:
                    self.logger.debug(ppp("Unexpected packet:", recv_pkt))
                    try:
                        self.logger.debug(ppp("Decrypted packet:",
                                              decrypt_pkt))
                    except:
                        pass
                    raise
        finally:
            self.logger.info(self.vapi.ppcli("show error"))
            self.logger.info(self.vapi.ppcli("show ipsec all"))
        self.verify_counters6(p, p, count)


class IpsecTun6Tests(IpsecTun6):
    """ UT test methods for Tunnel v6 """

    def test_tun_basic66(self):
        """ ipsec 6o6 tunnel basic test """
        self.verify_tun_66(self.params[socket.AF_INET6], count=1)

    def test_tun_burst66(self):
        """ ipsec 6o6 tunnel burst test """
        self.verify_tun_66(self.params[socket.AF_INET6], count=257)


class IpsecTun46Tests(IpsecTun4Tests, IpsecTun6Tests):
    """ UT test methods for Tunnel v6 & v4 """
    pass


if __name__ == '__main__':
    unittest.main(testRunner=VppTestRunner)