3 # Copyright (c) 2020 Cisco and/or its affiliates.
5 # SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
7 # Licensed under the Apache License 2.0 or
8 # GNU General Public License v2.0 or later; you may not use this file
9 # except in compliance with one of these Licenses. You
10 # may obtain a copy of the Licenses at:
12 # http://www.apache.org/licenses/LICENSE-2.0
13 # https://www.gnu.org/licenses/old-licenses/gpl-2.0-standalone.html
15 # Note: If this file is linked with Scapy, which is GPLv2+, your use of it
16 # must be under GPLv2+. If at any point in the future it is no longer linked
17 # with Scapy (or other GPLv2+ licensed software), you are free to choose Apache 2.
19 # Unless required by applicable law or agreed to in writing, software
20 # distributed under the License is distributed on an "AS IS" BASIS,
21 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
22 # See the License for the specific language governing permissions and
23 # limitations under the License.
25 """Traffic script for IPsec verification."""
29 from ipaddress import ip_address
30 from scapy.layers.inet import IP
31 from scapy.layers.inet6 import IPv6, ICMPv6ND_NS
32 from scapy.layers.ipsec import SecurityAssociation, ESP
33 from scapy.layers.l2 import Ether
34 from scapy.packet import Raw
36 from .PacketVerifier import RxQueue, TxQueue
37 from .TrafficScriptArg import TrafficScriptArg
41 pkt_recv, ip_layer, src_mac, dst_mac, src_tun, dst_tun, src_ip, dst_ip,
43 """Check received IPsec packet.
45 :param pkt_recv: Received packet to verify.
46 :param ip_layer: Scapy IP layer.
47 :param src_mac: Source MAC address.
48 :param dst_mac: Destination MAC address.
49 :param src_tun: IPsec tunnel source address.
50 :param dst_tun: IPsec tunnel destination address.
51 :param src_ip: Source IP/IPv6 address of original IP/IPv6 packet.
52 :param dst_ip: Destination IP/IPv6 address of original IP/IPv6 packet.
53 :param sa_in: IPsec SA for packet decryption.
54 :type pkt_recv: scapy.Ether
55 :type ip_layer: scapy.layers.inet.IP or scapy.layers.inet6.IPv6
62 :type sa_in: scapy.layers.ipsec.SecurityAssociation
63 :raises RuntimeError: If received packet is invalid.
65 if pkt_recv[Ether].src != src_mac:
67 f"Received frame has invalid source MAC address: "
68 f"{pkt_recv[Ether].src} should be: {src_mac}"
71 if pkt_recv[Ether].dst != dst_mac:
73 f"Received frame has invalid destination MAC address: "
74 f"{pkt_recv[Ether].dst} should be: {dst_mac}"
77 if not pkt_recv.haslayer(ip_layer):
79 f"Not an {ip_layer.name} packet received: {pkt_recv!r}"
82 if pkt_recv[ip_layer].src != src_tun:
84 f"Received packet has invalid source address: "
85 f"{pkt_recv[ip_layer].src} should be: {src_tun}"
88 if pkt_recv[ip_layer].dst != dst_tun:
90 f"Received packet has invalid destination address: "
91 f"{pkt_recv[ip_layer].dst} should be: {dst_tun}"
94 if not pkt_recv.haslayer(ESP):
95 raise RuntimeError(f"Not an ESP packet received: {pkt_recv!r}")
97 ip_pkt = pkt_recv[ip_layer]
98 d_pkt = sa_in.decrypt(ip_pkt)
100 if d_pkt[ip_layer].dst != dst_ip:
102 f"Decrypted packet has invalid destination address: "
103 f"{d_pkt[ip_layer].dst} should be: {dst_ip}"
106 if d_pkt[ip_layer].src != src_ip:
108 f"Decrypted packet has invalid source address: "
109 f"{d_pkt[ip_layer].src} should be: {src_ip}"
112 if ip_layer == IP and d_pkt[ip_layer].proto != 61:
114 f"Decrypted packet has invalid IP protocol: "
115 f"{d_pkt[ip_layer].proto} should be: 61"
119 def check_ip(pkt_recv, ip_layer, src_mac, dst_mac, src_ip, dst_ip):
120 """Check received IP/IPv6 packet.
122 :param pkt_recv: Received packet to verify.
123 :param ip_layer: Scapy IP layer.
124 :param src_mac: Source MAC address.
125 :param dst_mac: Destination MAC address.
126 :param src_ip: Source IP/IPv6 address.
127 :param dst_ip: Destination IP/IPv6 address.
128 :type pkt_recv: scapy.Ether
129 :type ip_layer: scapy.layers.inet.IP or scapy.layers.inet6.IPv6
134 :raises RuntimeError: If received packet is invalid.
136 if pkt_recv[Ether].src != src_mac:
138 f"Received frame has invalid source MAC address: "
139 f"{pkt_recv[Ether].src} should be: {src_mac}"
142 if pkt_recv[Ether].dst != dst_mac:
144 f"Received frame has invalid destination MAC address: "
145 f"{pkt_recv[Ether].dst} should be: {dst_mac}"
148 if not pkt_recv.haslayer(ip_layer):
150 f"Not an {ip_layer.name} packet received: {pkt_recv!r}"
153 if pkt_recv[ip_layer].dst != dst_ip:
155 f"Received packet has invalid destination address: "
156 f"{pkt_recv[ip_layer.name].dst} should be: {dst_ip}"
159 if pkt_recv[ip_layer].src != src_ip:
161 f"Received packet has invalid destination address: "
162 f"{pkt_recv[ip_layer.name].dst} should be: {src_ip}"
165 if ip_layer == IP and pkt_recv[ip_layer].proto != 61:
167 f"Received packet has invalid IP protocol: "
168 f"{pkt_recv[ip_layer].proto} should be: 61"
173 """Send and receive IPsec packet."""
175 args = TrafficScriptArg(
177 u"tx_src_mac", u"tx_dst_mac", u"rx_src_mac", u"rx_dst_mac",
178 u"src_ip", u"dst_ip", u"src_tun", u"dst_tun", u"crypto_alg",
179 u"crypto_key", u"integ_alg", u"integ_key", u"l_spi", u"r_spi"
183 tx_txq = TxQueue(args.get_arg(u"tx_if"))
184 tx_rxq = RxQueue(args.get_arg(u"tx_if"))
185 rx_txq = TxQueue(args.get_arg(u"rx_if"))
186 rx_rxq = RxQueue(args.get_arg(u"rx_if"))
188 tx_src_mac = args.get_arg(u"tx_src_mac")
189 tx_dst_mac = args.get_arg(u"tx_dst_mac")
190 rx_src_mac = args.get_arg(u"rx_src_mac")
191 rx_dst_mac = args.get_arg(u"rx_dst_mac")
192 src_ip = args.get_arg(u"src_ip")
193 dst_ip = args.get_arg(u"dst_ip")
194 src_tun = args.get_arg(u"src_tun")
195 dst_tun = args.get_arg(u"dst_tun")
196 crypto_alg = args.get_arg(u"crypto_alg")
197 crypto_key = args.get_arg(u"crypto_key")
198 integ_alg = args.get_arg(u"integ_alg")
199 integ_key = args.get_arg(u"integ_key")
200 l_spi = int(args.get_arg(u"l_spi"))
201 r_spi = int(args.get_arg(u"r_spi"))
203 ip_layer = IP if ip_address(src_ip).version == 4 else IPv6
204 ip_pkt = ip_layer(src=src_ip, dst=dst_ip, proto=61) if ip_layer == IP \
205 else ip_layer(src=src_ip, dst=dst_ip)
207 tunnel_in = ip_layer(src=src_tun, dst=dst_tun)
208 tunnel_out = ip_layer(src=dst_tun, dst=src_tun)
210 sa_in = SecurityAssociation(
211 ESP, spi=l_spi, crypt_algo=crypto_alg,
212 crypt_key=crypto_key.encode(encoding=u"utf-8"), auth_algo=integ_alg,
213 auth_key=integ_key.encode(encoding=u"utf-8"),
214 tunnel_header=tunnel_in
217 sa_out = SecurityAssociation(
218 ESP, spi=r_spi, crypt_algo=crypto_alg,
219 crypt_key=crypto_key.encode(encoding=u"utf-8"), auth_algo=integ_alg,
220 auth_key=integ_key.encode(encoding=u"utf-8"),
221 tunnel_header=tunnel_out
224 sent_packets = list()
225 tx_pkt_send = (Ether(src=tx_src_mac, dst=tx_dst_mac) / ip_pkt)
227 size_limit = 78 if ip_layer == IPv6 else 64
228 if len(tx_pkt_send) < size_limit:
229 tx_pkt_send[Raw].load += (b"\0" * (size_limit - len(tx_pkt_send)))
230 sent_packets.append(tx_pkt_send)
231 tx_txq.send(tx_pkt_send)
234 rx_pkt_recv = rx_rxq.recv(2)
236 if rx_pkt_recv is None:
237 raise RuntimeError(f"{ip_layer.name} packet Rx timeout")
239 if rx_pkt_recv.haslayer(ICMPv6ND_NS):
240 # read another packet in the queue if the current one is ICMPv6ND_NS
243 # otherwise process the current packet
247 rx_pkt_recv, ip_layer, rx_src_mac, rx_dst_mac, src_tun, dst_tun, src_ip,
251 ip_pkt = ip_layer(src=dst_ip, dst=src_ip, proto=61) if ip_layer == IP \
252 else ip_layer(src=dst_ip, dst=src_ip)
254 if len(ip_pkt) < (size_limit - 14):
255 ip_pkt[Raw].load += (b"\0" * (size_limit - 14 - len(ip_pkt)))
256 e_pkt = sa_out.encrypt(ip_pkt)
257 rx_pkt_send = (Ether(src=rx_dst_mac, dst=rx_src_mac) /
259 rx_txq.send(rx_pkt_send)
262 tx_pkt_recv = tx_rxq.recv(2, ignore=sent_packets)
264 if tx_pkt_recv is None:
265 raise RuntimeError(f"{ip_layer.name} packet Rx timeout")
267 if tx_pkt_recv.haslayer(ICMPv6ND_NS):
268 # read another packet in the queue if the current one is ICMPv6ND_NS
271 # otherwise process the current packet
274 check_ip(tx_pkt_recv, ip_layer, tx_dst_mac, tx_src_mac, dst_ip, src_ip)
279 if __name__ == u"__main__":