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/*
 * Copyright (c) 2015 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
  Copyright (c) 2004 Eliot Dresselhaus

  Permission is hereby granted, free of charge, to any person obtaining
  a copy of this software and associated documentation files (the
  "Software"), to deal in the Software without restriction, including
  without limitation the rights to use, copy, modify, merge, publish,
  distribute, sublicense, and/or sell copies of the Software, and to
  permit persons to whom the Software is furnished to do so, subject to
  the following conditions:

  The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#ifndef included_clib_byte_order_h
#define included_clib_byte_order_h

#include <vppinfra/clib.h>

#if (__BYTE_ORDER__)==( __ORDER_LITTLE_ENDIAN__)
#define CLIB_ARCH_IS_BIG_ENDIAN (0)
#define CLIB_ARCH_IS_LITTLE_ENDIAN (1)
#else
/* Default is big endian. */
#define CLIB_ARCH_IS_BIG_ENDIAN (1)
#define CLIB_ARCH_IS_LITTLE_ENDIAN (0)
#endif

/* Big/little endian. */
#define clib_arch_is_big_endian    CLIB_ARCH_IS_BIG_ENDIAN
#define clib_arch_is_little_endian CLIB_ARCH_IS_LITTLE_ENDIAN

always_inline u16
clib_byte_swap_u16 (u16 x)
{
  return __builtin_bswap16 (x);
}

always_inline i16
clib_byte_swap_i16 (i16 x)
{
  return clib_byte_swap_u16 (x);
}

always_inline u32
clib_byte_swap_u32 (u32 x)
{
  return __builtin_bswap32 (x);
}

always_inline i32
clib_byte_swap_i32 (i32 x)
{
  return clib_byte_swap_u32 (x);
}

always_inline u64
clib_byte_swap_u64 (u64 x)
{
  return __builtin_bswap64 (x);
}

always_inline i64
clib_byte_swap_i64 (i64 x)
{
  return clib_byte_swap_u64 (x);
}

#define _(sex,type)						\
/* HOST -> SEX */						\
always_inline type						\
clib_host_to_##sex##_##type (type x)				\
{								\
  if (! clib_arch_is_##sex##_endian)				\
    x = clib_byte_swap_##type (x);				\
  return x;							\
}								\
								\
always_inline type						\
clib_host_to_##sex##_mem_##type (type * x)			\
{								\
  type v = x[0];						\
  return clib_host_to_##sex##_##type (v);			\
}								\
								\
always_inline type						\
clib_host_to_##sex##_unaligned_mem_##type (type * x)		\
{								\
  type v = clib_mem_unaligned (x, type);			\
  return clib_host_to_##sex##_##type (v);			\
}								\
								\
/* SEX -> HOST */						\
always_inline type						\
clib_##sex##_to_host_##type (type x)				\
{ return clib_host_to_##sex##_##type (x); }			\
								\
always_inline type						\
clib_##sex##_to_host_mem_##type (type * x)			\
{ return clib_host_to_##sex##_mem_##type (x); }			\
								\
always_inline type						\
clib_##sex##_to_host_unaligned_mem_##type (type * x)		\
{ return clib_host_to_##sex##_unaligned_mem_##type (x); }

#ifndef __cplusplus
_(little, u16)
_(little, u32)
_(little, u64)
_(little, i16)
_(little, i32)
_(little, i64)
_(big, u16) _(big, u32) _(big, u64) _(big, i16) _(big, i32) _(big, i64)
#endif
#undef _
/* Network "net" alias for "big". */
#define _(type)						\
always_inline type					\
clib_net_to_host_##type (type x)			\
{ return clib_big_to_host_##type (x); }			\
							\
always_inline type					\
clib_net_to_host_mem_##type (type * x)			\
{ return clib_big_to_host_mem_##type (x); }		\
							\
always_inline type					\
clib_net_to_host_unaligned_mem_##type (type * x)	\
{ return clib_big_to_host_unaligned_mem_##type (x); }	\
							\
always_inline type					\
clib_host_to_net_##type (type x)			\
{ return clib_host_to_big_##type (x); }			\
							\
always_inline type					\
clib_host_to_net_mem_##type (type * x)			\
{ return clib_host_to_big_mem_##type (x); }		\
							\
always_inline type					\
clib_host_to_net_unaligned_mem_##type (type * x)	\
{ return clib_host_to_big_unaligned_mem_##type (x); }
#ifndef __cplusplus
  _(u16);
_(i16);
_(u32);
_(i32);
_(u64);
_(i64);
#endif

#undef _

/* Dummy endian swap functions for IEEE floating-point numbers */
/* *INDENT-OFF* */
always_inline f64 clib_net_to_host_f64 (f64 x) { return x; }
always_inline f64 clib_host_to_net_f64 (f64 x) { return x; }
always_inline f32 clib_net_to_host_f32 (f32 x) { return x; }
always_inline f32 clib_host_to_net_f32 (f32 x) { return x; }
/* *INDENT-ON* */

#endif /* included_clib_byte_order_h */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */
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#!/usr/bin/env python

import six
import unittest
from random import shuffle

from framework import VppTestCase, VppTestRunner

from scapy.packet import Raw
from scapy.layers.l2 import Ether, GRE
from scapy.layers.inet import IP, UDP, ICMP
from util import ppp, fragment_rfc791, fragment_rfc8200
from scapy.layers.inet6 import IPv6, IPv6ExtHdrFragment, ICMPv6ParamProblem,\
    ICMPv6TimeExceeded
from vpp_gre_interface import VppGreInterface, VppGre6Interface
from vpp_ip import DpoProto
from vpp_ip_route import VppIpRoute, VppRoutePath

# 35 is enough to have >257 400-byte fragments
test_packet_count = 35


class TestIPv4Reassembly(VppTestCase):
    """ IPv4 Reassembly """

    @classmethod
    def setUpClass(cls):
        super(TestIPv4Reassembly, cls).setUpClass()

        cls.create_pg_interfaces([0, 1])
        cls.src_if = cls.pg0
        cls.dst_if = cls.pg1

        # setup all interfaces
        for i in cls.pg_interfaces:
            i.admin_up()
            i.config_ip4()
            i.resolve_arp()

        # packet sizes
        cls.packet_sizes = [64, 512, 1518, 9018]
        cls.padding = " abcdefghijklmn"
        cls.create_stream(cls.packet_sizes)
        cls.create_fragments()

    def setUp(self):
        """ Test setup - force timeout on existing reassemblies """
        super(TestIPv4Reassembly, self).setUp()
        self.vapi.ip_reassembly_enable_disable(
            sw_if_index=self.src_if.sw_if_index, enable_ip4=True)
        self.vapi.ip_reassembly_set(timeout_ms=0, max_reassemblies=1000,
                                    expire_walk_interval_ms=10)
        self.sleep(.25)
        self.vapi.ip_reassembly_set(timeout_ms=1000000, max_reassemblies=1000,
                                    expire_walk_interval_ms=10000)

    def tearDown(self):
        super(TestIPv4Reassembly, self).tearDown()
        self.logger.debug(self.vapi.ppcli("show ip4-reassembly details"))
        self.logger.debug(self.vapi.ppcli("show buffers"))

    @classmethod
    def create_stream(cls, packet_sizes, packet_count=test_packet_count):
        """Create input packet stream

        :param list packet_sizes: Required packet sizes.
        """
        for i in range(0, packet_count):
            info = cls.create_packet_info(cls.src_if, cls.src_if)
            payload = cls.info_to_payload(info)
            p = (Ether(dst=cls.src_if.local_mac, src=cls.src_if.remote_mac) /
                 IP(id=info.index, src=cls.src_if.remote_ip4,
                    dst=cls.dst_if.remote_ip4) /
                 UDP(sport=1234, dport=5678) /
                 Raw(payload))
            size = packet_sizes[(i // 2) % len(packet_sizes)]
            cls.extend_packet(p, size, cls.padding)
            info.data = p

    @classmethod
    def create_fragments(cls):
        infos = cls._packet_infos
        cls.pkt_infos = []
        for index, info in six.iteritems(infos):
            p = info.data
            # cls.logger.debug(ppp("Packet:", p.__class__(str(p))))
            fragments_400 = fragment_rfc791(p, 400)
            fragments_300 = fragment_rfc791(p, 300)
            fragments_200 = [
                x for f in fragments_400 for x in fragment_rfc791(f, 200)]
            cls.pkt_infos.append(
                (index, fragments_400, fragments_300, fragments_200))
        cls.fragments_400 = [
            x for (_, frags, _, _) in cls.pkt_infos for x in frags]
        cls.fragments_300 = [
            x for (_, _, frags, _) in cls.pkt_infos for x in frags]
        cls.fragments_200 = [
            x for (_, _, _, frags) in cls.pkt_infos for x in frags]
        cls.logger.debug("Fragmented %s packets into %s 400-byte fragments, "
                         "%s 300-byte fragments and %s 200-byte fragments" %
                         (len(infos), len(cls.fragments_400),
                             len(cls.fragments_300), len(cls.fragments_200)))

    def verify_capture(self, capture, dropped_packet_indexes=[]):
        """Verify captured packet stream.

        :param list capture: Captured packet stream.
        """
        info = None
        seen = set()
        for packet in capture:
            try:
                self.logger.debug(ppp("Got packet:", packet))
                ip = packet[IP]
                udp = packet[UDP]
                payload_info = self.payload_to_info(str(packet[Raw]))
                packet_index = payload_info.index
                self.assertTrue(
                    packet_index not in dropped_packet_indexes,
                    ppp("Packet received, but should be dropped:", packet))
                if packet_index in seen:
                    raise Exception(ppp("Duplicate packet received", packet))
                seen.add(packet_index)
                self.assertEqual(payload_info.dst, self.src_if.sw_if_index)
                info = self._packet_infos[packet_index]
                self.assertTrue(info is not None)
                self.assertEqual(packet_index, info.index)
                saved_packet = info.data
                self.assertEqual(ip.src, saved_packet[IP].src)
                self.assertEqual(ip.dst, saved_packet[IP].dst)
                self.assertEqual(udp.payload, saved_packet[UDP].payload)
            except Exception:
                self.logger.error(ppp("Unexpected or invalid packet:", packet))
                raise
        for index in self._packet_infos:
            self.assertTrue(index in seen or index in dropped_packet_indexes,
                            "Packet with packet_index %d not received" % index)

    def test_reassembly(self):
        """ basic reassembly """

        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_200)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all again to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_200)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_reversed(self):
        """ reverse order reassembly """

        fragments = list(self.fragments_200)
        fragments.reverse()

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.packet_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all again to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.packet_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_5737(self):
        """ fragment length + ip header size > 65535 """
        self.vapi.cli("clear errors")
        raw = ('E\x00\x00\x88,\xf8\x1f\xfe@\x01\x98\x00\xc0\xa8\n-\xc0\xa8\n'
               '\x01\x08\x00\xf0J\xed\xcb\xf1\xf5Test-group: IPv4.IPv4.ipv4-'
               'message.Ethernet-Payload.IPv4-Packet.IPv4-Header.Fragment-Of'
               'fset; Test-case: 5737')

        malformed_packet = (Ether(dst=self.src_if.local_mac,
                                  src=self.src_if.remote_mac) /
                            IP(raw))
        p = (Ether(dst=self.src_if.local_mac, src=self.src_if.remote_mac) /
             IP(id=1000, src=self.src_if.remote_ip4,
                dst=self.dst_if.remote_ip4) /
             UDP(sport=1234, dport=5678) /
             Raw("X" * 1000))
        valid_fragments = fragment_rfc791(p, 400)

        self.pg_enable_capture()
        self.src_if.add_stream([malformed_packet] + valid_fragments)
        self.pg_start()

        self.dst_if.get_capture(1)
        self.assert_packet_counter_equal("ip4-reassembly-feature", 1)
        # TODO remove above, uncomment below once clearing of counters
        # is supported
        # self.assert_packet_counter_equal(
        #     "/err/ip4-reassembly-feature/malformed packets", 1)

    def test_44924(self):
        """ compress tiny fragments """
        packets = [(Ether(dst=self.src_if.local_mac,
                          src=self.src_if.remote_mac) /
                    IP(id=24339, flags="MF", frag=0, ttl=64,
                       src=self.src_if.remote_ip4,
                       dst=self.dst_if.remote_ip4) /
                    ICMP(type="echo-request", code=0, id=0x1fe6, seq=0x2407) /
                    Raw(load='Test-group: IPv4')),
                   (Ether(dst=self.src_if.local_mac,
                          src=self.src_if.remote_mac) /
                    IP(id=24339, flags="MF", frag=3, ttl=64,
                       src=self.src_if.remote_ip4,
                       dst=self.dst_if.remote_ip4) /
                    ICMP(type="echo-request", code=0, id=0x1fe6, seq=0x2407) /
                    Raw(load='.IPv4.Fragmentation.vali')),
                   (Ether(dst=self.src_if.local_mac,
                          src=self.src_if.remote_mac) /
                    IP(id=24339, frag=6, ttl=64,
                       src=self.src_if.remote_ip4,
                       dst=self.dst_if.remote_ip4) /
                    ICMP(type="echo-request", code=0, id=0x1fe6, seq=0x2407) /
                    Raw(load='d; Test-case: 44924'))
                   ]

        self.pg_enable_capture()
        self.src_if.add_stream(packets)
        self.pg_start()

        self.dst_if.get_capture(1)

    def test_frag_1(self):
        """ fragment of size 1 """
        self.vapi.cli("clear errors")
        malformed_packets = [(Ether(dst=self.src_if.local_mac,
                                    src=self.src_if.remote_mac) /
                              IP(id=7, len=21, flags="MF", frag=0, ttl=64,
                                 src=self.src_if.remote_ip4,
                                 dst=self.dst_if.remote_ip4) /
                              ICMP(type="echo-request")),
                             (Ether(dst=self.src_if.local_mac,
                                    src=self.src_if.remote_mac) /
                              IP(id=7, len=21, frag=1, ttl=64,
                                 src=self.src_if.remote_ip4,
                                 dst=self.dst_if.remote_ip4) /
                              Raw(load='\x08')),
                             ]

        p = (Ether(dst=self.src_if.local_mac, src=self.src_if.remote_mac) /
             IP(id=1000, src=self.src_if.remote_ip4,
                dst=self.dst_if.remote_ip4) /
             UDP(sport=1234, dport=5678) /
             Raw("X" * 1000))
        valid_fragments = fragment_rfc791(p, 400)

        self.pg_enable_capture()
        self.src_if.add_stream(malformed_packets + valid_fragments)
        self.pg_start()

        self.dst_if.get_capture(1)

        self.assert_packet_counter_equal("ip4-reassembly-feature", 1)
        # TODO remove above, uncomment below once clearing of counters
        # is supported
        # self.assert_packet_counter_equal(
        #     "/err/ip4-reassembly-feature/malformed packets", 1)

    def test_random(self):
        """ random order reassembly """

        fragments = list(self.fragments_200)
        shuffle(fragments)

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.packet_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all again to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.packet_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_duplicates(self):
        """ duplicate fragments """

        fragments = [
            x for (_, frags, _, _) in self.pkt_infos
            for x in frags
            for _ in range(0, min(2, len(frags)))
        ]

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_overlap1(self):
        """ overlapping fragments case #1 """

        fragments = []
        for _, _, frags_300, frags_200 in self.pkt_infos:
            if len(frags_300) == 1:
                fragments.extend(frags_300)
            else:
                for i, j in zip(frags_200, frags_300):
                    fragments.extend(i)
                    fragments.extend(j)

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_overlap2(self):
        """ overlapping fragments case #2 """

        fragments = []
        for _, _, frags_300, frags_200 in self.pkt_infos:
            if len(frags_300) == 1:
                fragments.extend(frags_300)
            else:
                # care must be taken here so that there are no fragments
                # received by vpp after reassembly is finished, otherwise
                # new reassemblies will be started and packet generator will
                # freak out when it detects unfreed buffers
                zipped = zip(frags_300, frags_200)
                for i, j in zipped[:-1]:
                    fragments.extend(i)
                    fragments.extend(j)
                fragments.append(zipped[-1][0])

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_timeout_inline(self):
        """ timeout (inline) """

        dropped_packet_indexes = set(
            index for (index, frags, _, _) in self.pkt_infos if len(frags) > 1
        )

        self.vapi.ip_reassembly_set(timeout_ms=0, max_reassemblies=1000,
                                    expire_walk_interval_ms=10000)

        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_400)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        self.src_if.assert_nothing_captured()

    def test_timeout_cleanup(self):
        """ timeout (cleanup) """

        # whole packets + fragmented packets sans last fragment
        fragments = [
            x for (_, frags_400, _, _) in self.pkt_infos
            for x in frags_400[:-1 if len(frags_400) > 1 else None]
        ]

        # last fragments for fragmented packets
        fragments2 = [frags_400[-1]
                      for (_, frags_400, _, _) in self.pkt_infos
                      if len(frags_400) > 1]

        dropped_packet_indexes = set(
            index for (index, frags_400, _, _) in self.pkt_infos
            if len(frags_400) > 1)

        self.vapi.ip_reassembly_set(timeout_ms=100, max_reassemblies=1000,
                                    expire_walk_interval_ms=50)

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        self.sleep(.25, "wait before sending rest of fragments")

        self.src_if.add_stream(fragments2)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        self.src_if.assert_nothing_captured()

    def test_disabled(self):
        """ reassembly disabled """

        dropped_packet_indexes = set(
            index for (index, frags_400, _, _) in self.pkt_infos
            if len(frags_400) > 1)

        self.vapi.ip_reassembly_set(timeout_ms=1000, max_reassemblies=0,
                                    expire_walk_interval_ms=10000)

        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_400)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        self.src_if.assert_nothing_captured()


class TestIPv6Reassembly(VppTestCase):
    """ IPv6 Reassembly """

    @classmethod
    def setUpClass(cls):
        super(TestIPv6Reassembly, cls).setUpClass()

        cls.create_pg_interfaces([0, 1])
        cls.src_if = cls.pg0
        cls.dst_if = cls.pg1

        # setup all interfaces
        for i in cls.pg_interfaces:
            i.admin_up()
            i.config_ip6()
            i.resolve_ndp()

        # packet sizes
        cls.packet_sizes = [64, 512, 1518, 9018]
        cls.padding = " abcdefghijklmn"
        cls.create_stream(cls.packet_sizes)
        cls.create_fragments()

    def setUp(self):
        """ Test setup - force timeout on existing reassemblies """
        super(TestIPv6Reassembly, self).setUp()
        self.vapi.ip_reassembly_enable_disable(
            sw_if_index=self.src_if.sw_if_index, enable_ip6=True)
        self.vapi.ip_reassembly_set(timeout_ms=0, max_reassemblies=1000,
                                    expire_walk_interval_ms=10, is_ip6=1)
        self.sleep(.25)
        self.vapi.ip_reassembly_set(timeout_ms=1000000, max_reassemblies=1000,
                                    expire_walk_interval_ms=10000, is_ip6=1)
        self.logger.debug(self.vapi.ppcli("show ip6-reassembly details"))
        self.logger.debug(self.vapi.ppcli("show buffers"))

    def tearDown(self):
        super(TestIPv6Reassembly, self).tearDown()
        self.logger.debug(self.vapi.ppcli("show ip6-reassembly details"))
        self.logger.debug(self.vapi.ppcli("show buffers"))

    @classmethod
    def create_stream(cls, packet_sizes, packet_count=test_packet_count):
        """Create input packet stream for defined interface.

        :param list packet_sizes: Required packet sizes.
        """
        for i in range(0, packet_count):
            info = cls.create_packet_info(cls.src_if, cls.src_if)
            payload = cls.info_to_payload(info)
            p = (Ether(dst=cls.src_if.local_mac, src=cls.src_if.remote_mac) /
                 IPv6(src=cls.src_if.remote_ip6,
                      dst=cls.dst_if.remote_ip6) /
                 UDP(sport=1234, dport=5678) /
                 Raw(payload))
            size = packet_sizes[(i // 2) % len(packet_sizes)]
            cls.extend_packet(p, size, cls.padding)
            info.data = p

    @classmethod
    def create_fragments(cls):
        infos = cls._packet_infos
        cls.pkt_infos = []
        for index, info in six.iteritems(infos):
            p = info.data
            # cls.logger.debug(ppp("Packet:", p.__class__(str(p))))
            fragments_400 = fragment_rfc8200(p, info.index, 400)
            fragments_300 = fragment_rfc8200(p, info.index, 300)
            cls.pkt_infos.append((index, fragments_400, fragments_300))
        cls.fragments_400 = [
            x for _, frags, _ in cls.pkt_infos for x in frags]
        cls.fragments_300 = [
            x for _, _, frags in cls.pkt_infos for x in frags]
        cls.logger.debug("Fragmented %s packets into %s 400-byte fragments, "
                         "and %s 300-byte fragments" %
                         (len(infos), len(cls.fragments_400),
                             len(cls.fragments_300)))

    def verify_capture(self, capture, dropped_packet_indexes=[]):
        """Verify captured packet strea .

        :param list capture: Captured packet stream.
        """
        info = None
        seen = set()
        for packet in capture:
            try:
                self.logger.debug(ppp("Got packet:", packet))
                ip = packet[IPv6]
                udp = packet[UDP]
                payload_info = self.payload_to_info(str(packet[Raw]))
                packet_index = payload_info.index
                self.assertTrue(
                    packet_index not in dropped_packet_indexes,
                    ppp("Packet received, but should be dropped:", packet))
                if packet_index in seen:
                    raise Exception(ppp("Duplicate packet received", packet))
                seen.add(packet_index)
                self.assertEqual(payload_info.dst, self.src_if.sw_if_index)
                info = self._packet_infos[packet_index]
                self.assertTrue(info is not None)
                self.assertEqual(packet_index, info.index)
                saved_packet = info.data
                self.assertEqual(ip.src, saved_packet[IPv6].src)
                self.assertEqual(ip.dst, saved_packet[IPv6].dst)
                self.assertEqual(udp.payload, saved_packet[UDP].payload)
            except Exception:
                self.logger.error(ppp("Unexpected or invalid packet:", packet))
                raise
        for index in self._packet_infos:
            self.assertTrue(index in seen or index in dropped_packet_indexes,
                            "Packet with packet_index %d not received" % index)

    def test_reassembly(self):
        """ basic reassembly """

        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_400)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all again to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_400)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_reversed(self):
        """ reverse order reassembly """

        fragments = list(self.fragments_400)
        fragments.reverse()

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all again to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_random(self):
        """ random order reassembly """

        fragments = list(self.fragments_400)
        shuffle(fragments)

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

        # run it all again to verify correctness
        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_duplicates(self):
        """ duplicate fragments """

        fragments = [
            x for (_, frags, _) in self.pkt_infos
            for x in frags
            for _ in range(0, min(2, len(frags)))
        ]

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)
        self.src_if.assert_nothing_captured()

    def test_overlap1(self):
        """ overlapping fragments case #1 """

        fragments = []
        for _, frags_400, frags_300 in self.pkt_infos:
            if len(frags_300) == 1:
                fragments.extend(frags_400)
            else:
                for i, j in zip(frags_300, frags_400):
                    fragments.extend(i)
                    fragments.extend(j)

        dropped_packet_indexes = set(
            index for (index, _, frags) in self.pkt_infos if len(frags) > 1
        )

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        self.src_if.assert_nothing_captured()

    def test_overlap2(self):
        """ overlapping fragments case #2 """

        fragments = []
        for _, frags_400, frags_300 in self.pkt_infos:
            if len(frags_400) == 1:
                fragments.extend(frags_400)
            else:
                # care must be taken here so that there are no fragments
                # received by vpp after reassembly is finished, otherwise
                # new reassemblies will be started and packet generator will
                # freak out when it detects unfreed buffers
                zipped = zip(frags_400, frags_300)
                for i, j in zipped[:-1]:
                    fragments.extend(i)
                    fragments.extend(j)
                fragments.append(zipped[-1][0])

        dropped_packet_indexes = set(
            index for (index, _, frags) in self.pkt_infos if len(frags) > 1
        )

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        self.src_if.assert_nothing_captured()

    def test_timeout_inline(self):
        """ timeout (inline) """

        dropped_packet_indexes = set(
            index for (index, frags, _) in self.pkt_infos if len(frags) > 1
        )

        self.vapi.ip_reassembly_set(timeout_ms=0, max_reassemblies=1000,
                                    expire_walk_interval_ms=10000, is_ip6=1)

        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_400)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        pkts = self.src_if.get_capture(
            expected_count=len(dropped_packet_indexes))
        for icmp in pkts:
            self.assertIn(ICMPv6TimeExceeded, icmp)
            self.assertIn(IPv6ExtHdrFragment, icmp)
            self.assertIn(icmp[IPv6ExtHdrFragment].id, dropped_packet_indexes)
            dropped_packet_indexes.remove(icmp[IPv6ExtHdrFragment].id)

    def test_timeout_cleanup(self):
        """ timeout (cleanup) """

        # whole packets + fragmented packets sans last fragment
        fragments = [
            x for (_, frags_400, _) in self.pkt_infos
            for x in frags_400[:-1 if len(frags_400) > 1 else None]
        ]

        # last fragments for fragmented packets
        fragments2 = [frags_400[-1]
                      for (_, frags_400, _) in self.pkt_infos
                      if len(frags_400) > 1]

        dropped_packet_indexes = set(
            index for (index, frags_400, _) in self.pkt_infos
            if len(frags_400) > 1)

        self.vapi.ip_reassembly_set(timeout_ms=100, max_reassemblies=1000,
                                    expire_walk_interval_ms=50)

        self.vapi.ip_reassembly_set(timeout_ms=100, max_reassemblies=1000,
                                    expire_walk_interval_ms=50, is_ip6=1)

        self.pg_enable_capture()
        self.src_if.add_stream(fragments)
        self.pg_start()

        self.sleep(.25, "wait before sending rest of fragments")

        self.src_if.add_stream(fragments2)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        pkts = self.src_if.get_capture(
            expected_count=len(dropped_packet_indexes))
        for icmp in pkts:
            self.assertIn(ICMPv6TimeExceeded, icmp)
            self.assertIn(IPv6ExtHdrFragment, icmp)
            self.assertIn(icmp[IPv6ExtHdrFragment].id, dropped_packet_indexes)
            dropped_packet_indexes.remove(icmp[IPv6ExtHdrFragment].id)

    def test_disabled(self):
        """ reassembly disabled """

        dropped_packet_indexes = set(
            index for (index, frags_400, _) in self.pkt_infos
            if len(frags_400) > 1)

        self.vapi.ip_reassembly_set(timeout_ms=1000, max_reassemblies=0,
                                    expire_walk_interval_ms=10000, is_ip6=1)

        self.pg_enable_capture()
        self.src_if.add_stream(self.fragments_400)
        self.pg_start()

        packets = self.dst_if.get_capture(
            len(self.pkt_infos) - len(dropped_packet_indexes))
        self.verify_capture(packets, dropped_packet_indexes)
        self.src_if.assert_nothing_captured()

    def test_missing_upper(self):
        """ missing upper layer """
        p = (Ether(dst=self.src_if.local_mac, src=self.src_if.remote_mac) /
             IPv6(src=self.src_if.remote_ip6,
                  dst=self.src_if.local_ip6) /
             UDP(sport=1234, dport=5678) /
             Raw())
        self.extend_packet(p, 1000, self.padding)
        fragments = fragment_rfc8200(p, 1, 500)
        bad_fragment = p.__class__(str(fragments[1]))
        bad_fragment[IPv6ExtHdrFragment].nh = 59
        bad_fragment[IPv6ExtHdrFragment].offset = 0
        self.pg_enable_capture()
        self.src_if.add_stream([bad_fragment])
        self.pg_start()
        pkts = self.src_if.get_capture(expected_count=1)
        icmp = pkts[0]
        self.assertIn(ICMPv6ParamProblem, icmp)
        self.assert_equal(icmp[ICMPv6ParamProblem].code, 3, "ICMP code")

    def test_invalid_frag_size(self):
        """ fragment size not a multiple of 8 """
        p = (Ether(dst=self.src_if.local_mac, src=self.src_if.remote_mac) /
             IPv6(src=self.src_if.remote_ip6,
                  dst=self.src_if.local_ip6) /
             UDP(sport=1234, dport=5678) /
             Raw())
        self.extend_packet(p, 1000, self.padding)
        fragments = fragment_rfc8200(p, 1, 500)
        bad_fragment = fragments[0]
        self.extend_packet(bad_fragment, len(bad_fragment) + 5)
        self.pg_enable_capture()
        self.src_if.add_stream([bad_fragment])
        self.pg_start()
        pkts = self.src_if.get_capture(expected_count=1)
        icmp = pkts[0]
        self.assertIn(ICMPv6ParamProblem, icmp)
        self.assert_equal(icmp[ICMPv6ParamProblem].code, 0, "ICMP code")

    def test_invalid_packet_size(self):
        """ total packet size > 65535 """
        p = (Ether(dst=self.src_if.local_mac, src=self.src_if.remote_mac) /
             IPv6(src=self.src_if.remote_ip6,
                  dst=self.src_if.local_ip6) /
             UDP(sport=1234, dport=5678) /
             Raw())
        self.extend_packet(p, 1000, self.padding)
        fragments = fragment_rfc8200(p, 1, 500)
        bad_fragment = fragments[1]
        bad_fragment[IPv6ExtHdrFragment].offset = 65500
        self.pg_enable_capture()
        self.src_if.add_stream([bad_fragment])
        self.pg_start()
        pkts = self.src_if.get_capture(expected_count=1)
        icmp = pkts[0]
        self.assertIn(ICMPv6ParamProblem, icmp)
        self.assert_equal(icmp[ICMPv6ParamProblem].code, 0, "ICMP code")


class TestIPv4ReassemblyLocalNode(VppTestCase):
    """ IPv4 Reassembly for packets coming to ip4-local node """

    @classmethod
    def setUpClass(cls):
        super(TestIPv4ReassemblyLocalNode, cls).setUpClass()

        cls.create_pg_interfaces([0])
        cls.src_dst_if = cls.pg0

        # setup all interfaces
        for i in cls.pg_interfaces:
            i.admin_up()
            i.config_ip4()
            i.resolve_arp()

        cls.padding = " abcdefghijklmn"
        cls.create_stream()
        cls.create_fragments()

    def setUp(self):
        """ Test setup - force timeout on existing reassemblies """
        super(TestIPv4ReassemblyLocalNode, self).setUp()
        self.vapi.ip_reassembly_set(timeout_ms=0, max_reassemblies=1000,
                                    expire_walk_interval_ms=10)
        self.sleep(.25)
        self.vapi.ip_reassembly_set(timeout_ms=1000000, max_reassemblies=1000,
                                    expire_walk_interval_ms=10000)

    def tearDown(self):
        super(TestIPv4ReassemblyLocalNode, self).tearDown()
        self.logger.debug(self.vapi.ppcli("show ip4-reassembly details"))
        self.logger.debug(self.vapi.ppcli("show buffers"))

    @classmethod
    def create_stream(cls, packet_count=test_packet_count):
        """Create input packet stream for defined interface.

        :param list packet_sizes: Required packet sizes.
        """
        for i in range(0, packet_count):
            info = cls.create_packet_info(cls.src_dst_if, cls.src_dst_if)
            payload = cls.info_to_payload(info)
            p = (Ether(dst=cls.src_dst_if.local_mac,
                       src=cls.src_dst_if.remote_mac) /
                 IP(id=info.index, src=cls.src_dst_if.remote_ip4,
                    dst=cls.src_dst_if.local_ip4) /
                 ICMP(type='echo-request', id=1234) /
                 Raw(payload))
            cls.extend_packet(p, 1518, cls.padding)
            info.data = p

    @classmethod
    def create_fragments(cls):
        infos = cls._packet_infos
        cls.pkt_infos = []
        for index, info in six.iteritems(infos):
            p = info.data
            # cls.logger.debug(ppp("Packet:", p.__class__(str(p))))
            fragments_300 = fragment_rfc791(p, 300)
            cls.pkt_infos.append((index, fragments_300))
        cls.fragments_300 = [x for (_, frags) in cls.pkt_infos for x in frags]
        cls.logger.debug("Fragmented %s packets into %s 300-byte fragments" %
                         (len(infos), len(cls.fragments_300)))

    def verify_capture(self, capture):
        """Verify captured packet stream.

        :param list capture: Captured packet stream.
        """
        info = None
        seen = set()
        for packet in capture:
            try:
                self.logger.debug(ppp("Got packet:", packet))
                ip = packet[IP]
                icmp = packet[ICMP]
                payload_info = self.payload_to_info(str(packet[Raw]))
                packet_index = payload_info.index
                if packet_index in seen:
                    raise Exception(ppp("Duplicate packet received", packet))
                seen.add(packet_index)
                self.assertEqual(payload_info.dst, self.src_dst_if.sw_if_index)
                info = self._packet_infos[packet_index]
                self.assertIsNotNone(info)
                self.assertEqual(packet_index, info.index)
                saved_packet = info.data
                self.assertEqual(ip.src, saved_packet[IP].dst)
                self.assertEqual(ip.dst, saved_packet[IP].src)
                self.assertEqual(icmp.type, 0)  # echo reply
                self.assertEqual(icmp.id, saved_packet[ICMP].id)
                self.assertEqual(icmp.payload, saved_packet[ICMP].payload)
            except Exception:
                self.logger.error(ppp("Unexpected or invalid packet:", packet))
                raise
        for index in self._packet_infos:
            self.assertIn(index, seen,
                          "Packet with packet_index %d not received" % index)

    def test_reassembly(self):
        """ basic reassembly """

        self.pg_enable_capture()
        self.src_dst_if.add_stream(self.fragments_300)
        self.pg_start()

        packets = self.src_dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)

        # run it all again to verify correctness
        self.pg_enable_capture()
        self.src_dst_if.add_stream(self.fragments_300)
        self.pg_start()

        packets = self.src_dst_if.get_capture(len(self.pkt_infos))
        self.verify_capture(packets)


class TestFIFReassembly(VppTestCase):
    """ Fragments in fragments reassembly """

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

        cls.create_pg_interfaces([0, 1])
        cls.src_if = cls.pg0
        cls.dst_if = cls.pg1
        for i in cls.pg_interfaces:
            i.admin_up()
            i.config_ip4()
            i.resolve_arp()
            i.config_ip6()
            i.resolve_ndp()

        cls.packet_sizes = [64, 512, 1518, 9018]
        cls.padding = " abcdefghijklmn"

    def setUp(self):
        """ Test setup - force timeout on existing reassemblies """
        super(TestFIFReassembly, self).setUp()
        self.vapi.ip_reassembly_enable_disable(
            sw_if_index=self.src_if.sw_if_index, enable_ip4=True,
            enable_ip6=True)
        self.vapi.ip_reassembly_enable_disable(
            sw_if_index=self.dst_if.sw_if_index, enable_ip4=True,
            enable_ip6=True)
        self.vapi.ip_reassembly_set(timeout_ms=0, max_reassemblies=1000,
                                    expire_walk_interval_ms=10)
        self.vapi.ip_reassembly_set(timeout_ms=0, max_reassemblies=1000,
                                    expire_walk_interval_ms=10, is_ip6=1)
        self.sleep(.25)
        self.vapi.ip_reassembly_set(timeout_ms=1000000, max_reassemblies=1000,
                                    expire_walk_interval_ms=10000)
        self.vapi.ip_reassembly_set(timeout_ms=1000000, max_reassemblies=1000,
                                    expire_walk_interval_ms=10000, is_ip6=1)

    def tearDown(self):
        self.logger.debug(self.vapi.ppcli("show ip4-reassembly details"))
        self.logger.debug(self.vapi.ppcli("show ip6-reassembly details"))
        self.logger.debug(self.vapi.ppcli("show buffers"))
        super(TestFIFReassembly, self).tearDown()

    def verify_capture(self, capture, ip_class, dropped_packet_indexes=[]):
        """Verify captured packet stream.

        :param list capture: Captured packet stream.
        """
        info = None
        seen = set()
        for packet in capture:
            try:
                self.logger.debug(ppp("Got packet:", packet))
                ip = packet[ip_class]
                udp = packet[UDP]
                payload_info = self.payload_to_info(str(packet[Raw]))
                packet_index = payload_info.index
                self.assertTrue(
                    packet_index not in dropped_packet_indexes,
                    ppp("Packet received, but should be dropped:", packet))
                if packet_index in seen:
                    raise Exception(ppp("Duplicate packet received", packet))
                seen.add(packet_index)
                self.assertEqual(payload_info.dst, self.dst_if.sw_if_index)
                info = self._packet_infos[packet_index]
                self.assertTrue(info is not None)
                self.assertEqual(packet_index, info.index)
                saved_packet = info.data
                self.assertEqual(ip.src, saved_packet[ip_class].src)
                self.assertEqual(ip.dst, saved_packet[ip_class].dst)
                self.assertEqual(udp.payload, saved_packet[UDP].payload)
            except Exception:
                self.logger.error(ppp("Unexpected or invalid packet:", packet))
                raise
        for index in self._packet_infos:
            self.assertTrue(index in seen or index in dropped_packet_indexes,
                            "Packet with packet_index %d not received" % index)

    def test_fif4(self):
        """ Fragments in fragments (4o4) """

        # TODO this should be ideally in setUpClass, but then we hit a bug
        # with VppIpRoute incorrectly reporting it's present when it's not
        # so we need to manually remove the vpp config, thus we cannot have
        # it shared for multiple test cases
        self.tun_ip4 = "1.1.1.2"

        self.gre4 = VppGreInterface(self, self.src_if.local_ip4, self.tun_ip4)
        self.gre4.add_vpp_config()
        self.gre4.admin_up()
        self.gre4.config_ip4()

        self.vapi.ip_reassembly_enable_disable(
            sw_if_index=self.gre4.sw_if_index, enable_ip4=True)

        self.route4 = VppIpRoute(self, self.tun_ip4, 32,
                                 [VppRoutePath(self.src_if.remote_ip4,
                                               self.src_if.sw_if_index)])
        self.route4.add_vpp_config()

        self.reset_packet_infos()
        for i in range(test_packet_count):
            info = self.create_packet_info(self.src_if, self.dst_if)
            payload = self.info_to_payload(info)
            # Ethernet header here is only for size calculation, thus it
            # doesn't matter how it's initialized. This is to ensure that
            # reassembled packet is not > 9000 bytes, so that it's not dropped
            p = (Ether() /
                 IP(id=i, src=self.src_if.remote_ip4,
                    dst=self.dst_if.remote_ip4) /
                 UDP(sport=1234, dport=5678) /
                 Raw(payload))
            size = self.packet_sizes[(i // 2) % len(self.packet_sizes)]
            self.extend_packet(p, size, self.padding)
            info.data = p[IP]  # use only IP part, without ethernet header

        fragments = [x for _, p in six.iteritems(self._packet_infos)
                     for x in fragment_rfc791(p.data, 400)]

        encapped_fragments = \
            [Ether(dst=self.src_if.local_mac, src=self.src_if.remote_mac) /
             IP(src=self.tun_ip4, dst=self.src_if.local_ip4) /
                GRE() /
                p
                for p in fragments]

        fragmented_encapped_fragments = \
            [x for p in encapped_fragments
             for x in fragment_rfc791(p, 200)]

        self.src_if.add_stream(fragmented_encapped_fragments)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        self.src_if.assert_nothing_captured()
        packets = self.dst_if.get_capture(len(self._packet_infos))
        self.verify_capture(packets, IP)

        # TODO remove gre vpp config by hand until VppIpRoute gets fixed
        # so that it's query_vpp_config() works as it should
        self.gre4.remove_vpp_config()
        self.logger.debug(self.vapi.ppcli("show interface"))

    def test_fif6(self):
        """ Fragments in fragments (6o6) """
        # TODO this should be ideally in setUpClass, but then we hit a bug
        # with VppIpRoute incorrectly reporting it's present when it's not
        # so we need to manually remove the vpp config, thus we cannot have
        # it shared for multiple test cases
        self.tun_ip6 = "1002::1"

        self.gre6 = VppGre6Interface(self, self.src_if.local_ip6, self.tun_ip6)
        self.gre6.add_vpp_config()
        self.gre6.admin_up()
        self.gre6.config_ip6()

        self.vapi.ip_reassembly_enable_disable(
            sw_if_index=self.gre6.sw_if_index, enable_ip6=True)

        self.route6 = VppIpRoute(self, self.tun_ip6, 128,
                                 [VppRoutePath(self.src_if.remote_ip6,
                                               self.src_if.sw_if_index,
                                               proto=DpoProto.DPO_PROTO_IP6)],
                                 is_ip6=1)
        self.route6.add_vpp_config()

        self.reset_packet_infos()
        for i in range(test_packet_count):
            info = self.create_packet_info(self.src_if, self.dst_if)
            payload = self.info_to_payload(info)
            # Ethernet header here is only for size calculation, thus it
            # doesn't matter how it's initialized. This is to ensure that
            # reassembled packet is not > 9000 bytes, so that it's not dropped
            p = (Ether() /
                 IPv6(src=self.src_if.remote_ip6, dst=self.dst_if.remote_ip6) /
                 UDP(sport=1234, dport=5678) /
                 Raw(payload))
            size = self.packet_sizes[(i // 2) % len(self.packet_sizes)]
            self.extend_packet(p, size, self.padding)
            info.data = p[IPv6]  # use only IPv6 part, without ethernet header

        fragments = [x for _, i in six.iteritems(self._packet_infos)
                     for x in fragment_rfc8200(
                         i.data, i.index, 400)]

        encapped_fragments = \
            [Ether(dst=self.src_if.local_mac, src=self.src_if.remote_mac) /
             IPv6(src=self.tun_ip6, dst=self.src_if.local_ip6) /
                GRE() /
                p
                for p in fragments]

        fragmented_encapped_fragments = \
            [x for p in encapped_fragments for x in (
                fragment_rfc8200(
                    p,
                    2 * len(self._packet_infos) + p[IPv6ExtHdrFragment].id,
                    200)
                if IPv6ExtHdrFragment in p else [p]
            )
            ]

        self.src_if.add_stream(fragmented_encapped_fragments)

        self.pg_enable_capture(self.pg_interfaces)
        self.pg_start()

        self.src_if.assert_nothing_captured()
        packets = self.dst_if.get_capture(len(self._packet_infos))
        self.verify_capture(packets, IPv6)

        # TODO remove gre vpp config by hand until VppIpRoute gets fixed
        # so that it's query_vpp_config() works as it should
        self.gre6.remove_vpp_config()


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