3 # Copyright (c) 2022 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
20 # Unless required by applicable law or agreed to in writing, software
21 # distributed under the License is distributed on an "AS IS" BASIS,
22 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
23 # See the License for the specific language governing permissions and
24 # limitations under the License.
26 """Traffic script for IPsec verification."""
30 from ipaddress import ip_address
31 from scapy.layers.inet import IP
32 from scapy.layers.inet6 import IPv6, ICMPv6ND_NS, ICMPv6MLReport2, ICMPv6ND_RA
33 from scapy.layers.ipsec import SecurityAssociation, ESP
34 from scapy.layers.l2 import Ether
35 from scapy.packet import Raw
37 from .PacketVerifier import RxQueue, TxQueue
38 from .TrafficScriptArg import TrafficScriptArg
42 pkt_recv, ip_layer, src_mac, dst_mac, src_tun, dst_tun, src_ip, dst_ip,
44 """Check received IPsec packet.
46 :param pkt_recv: Received packet to verify.
47 :param ip_layer: Scapy IP layer.
48 :param src_mac: Source MAC address.
49 :param dst_mac: Destination MAC address.
50 :param src_tun: IPsec tunnel source address.
51 :param dst_tun: IPsec tunnel destination address.
52 :param src_ip: Source IP/IPv6 address of original IP/IPv6 packet.
53 :param dst_ip: Destination IP/IPv6 address of original IP/IPv6 packet.
54 :param sa_in: IPsec SA for packet decryption.
55 :type pkt_recv: scapy.Ether
56 :type ip_layer: scapy.layers.inet.IP or scapy.layers.inet6.IPv6
63 :type sa_in: scapy.layers.ipsec.SecurityAssociation
64 :raises RuntimeError: If received packet is invalid.
66 if pkt_recv[Ether].src != src_mac:
68 f"Received frame has invalid source MAC address: "
69 f"{pkt_recv[Ether].src} should be: {src_mac}"
72 if pkt_recv[Ether].dst != dst_mac:
74 f"Received frame has invalid destination MAC address: "
75 f"{pkt_recv[Ether].dst} should be: {dst_mac}"
78 if not pkt_recv.haslayer(ip_layer):
80 f"Not an {ip_layer.name} packet received: {pkt_recv!r}"
83 if pkt_recv[ip_layer].src != src_tun:
85 f"Received packet has invalid source address: "
86 f"{pkt_recv[ip_layer].src} should be: {src_tun}"
89 if pkt_recv[ip_layer].dst != dst_tun:
91 f"Received packet has invalid destination address: "
92 f"{pkt_recv[ip_layer].dst} should be: {dst_tun}"
95 if not pkt_recv.haslayer(ESP):
96 raise RuntimeError(f"Not an ESP packet received: {pkt_recv!r}")
98 ip_pkt = pkt_recv[ip_layer]
99 d_pkt = sa_in.decrypt(ip_pkt)
101 if d_pkt[ip_layer].dst != dst_ip:
103 f"Decrypted packet has invalid destination address: "
104 f"{d_pkt[ip_layer].dst} should be: {dst_ip}"
107 if d_pkt[ip_layer].src != src_ip:
109 f"Decrypted packet has invalid source address: "
110 f"{d_pkt[ip_layer].src} should be: {src_ip}"
113 if ip_layer == IP and d_pkt[ip_layer].proto != 61:
115 f"Decrypted packet has invalid IP protocol: "
116 f"{d_pkt[ip_layer].proto} should be: 61"
120 def check_ip(pkt_recv, ip_layer, src_mac, dst_mac, src_ip, dst_ip):
121 """Check received IP/IPv6 packet.
123 :param pkt_recv: Received packet to verify.
124 :param ip_layer: Scapy IP layer.
125 :param src_mac: Source MAC address.
126 :param dst_mac: Destination MAC address.
127 :param src_ip: Source IP/IPv6 address.
128 :param dst_ip: Destination IP/IPv6 address.
129 :type pkt_recv: scapy.Ether
130 :type ip_layer: scapy.layers.inet.IP or scapy.layers.inet6.IPv6
135 :raises RuntimeError: If received packet is invalid.
137 if pkt_recv[Ether].src != src_mac:
139 f"Received frame has invalid source MAC address: "
140 f"{pkt_recv[Ether].src} should be: {src_mac}"
143 if pkt_recv[Ether].dst != dst_mac:
145 f"Received frame has invalid destination MAC address: "
146 f"{pkt_recv[Ether].dst} should be: {dst_mac}"
149 if not pkt_recv.haslayer(ip_layer):
151 f"Not an {ip_layer.name} packet received: {pkt_recv!r}"
154 if pkt_recv[ip_layer].dst != dst_ip:
156 f"Received packet has invalid destination address: "
157 f"{pkt_recv[ip_layer.name].dst} should be: {dst_ip}"
160 if pkt_recv[ip_layer].src != src_ip:
162 f"Received packet has invalid destination address: "
163 f"{pkt_recv[ip_layer.name].dst} should be: {src_ip}"
166 if ip_layer == IP and pkt_recv[ip_layer].proto != 61:
168 f"Received packet has invalid IP protocol: "
169 f"{pkt_recv[ip_layer].proto} should be: 61"
174 """Send and receive IPsec packet."""
176 args = TrafficScriptArg(
178 u"tx_src_mac", u"tx_dst_mac", u"rx_src_mac", u"rx_dst_mac",
179 u"src_ip", u"dst_ip", u"src_tun", u"dst_tun", u"crypto_alg",
180 u"crypto_key", u"integ_alg", u"integ_key", u"l_spi", u"r_spi"
184 tx_txq = TxQueue(args.get_arg(u"tx_if"))
185 tx_rxq = RxQueue(args.get_arg(u"tx_if"))
186 rx_txq = TxQueue(args.get_arg(u"rx_if"))
187 rx_rxq = RxQueue(args.get_arg(u"rx_if"))
189 tx_src_mac = args.get_arg(u"tx_src_mac")
190 tx_dst_mac = args.get_arg(u"tx_dst_mac")
191 rx_src_mac = args.get_arg(u"rx_src_mac")
192 rx_dst_mac = args.get_arg(u"rx_dst_mac")
193 src_ip = args.get_arg(u"src_ip")
194 dst_ip = args.get_arg(u"dst_ip")
195 src_tun = args.get_arg(u"src_tun")
196 dst_tun = args.get_arg(u"dst_tun")
197 crypto_alg = args.get_arg(u"crypto_alg")
198 crypto_key = args.get_arg(u"crypto_key")
199 integ_alg = args.get_arg(u"integ_alg")
200 integ_key = args.get_arg(u"integ_key")
201 l_spi = int(args.get_arg(u"l_spi"))
202 r_spi = int(args.get_arg(u"r_spi"))
204 ip_layer = IP if ip_address(src_ip).version == 4 else IPv6
205 ip_pkt = ip_layer(src=src_ip, dst=dst_ip, proto=61) if ip_layer == IP \
206 else ip_layer(src=src_ip, dst=dst_ip)
208 tunnel_in = ip_layer(src=src_tun, dst=dst_tun)
209 tunnel_out = ip_layer(src=dst_tun, dst=src_tun)
211 sa_in = SecurityAssociation(
212 ESP, spi=l_spi, crypt_algo=crypto_alg,
213 crypt_key=crypto_key.encode(encoding=u"utf-8"), auth_algo=integ_alg,
214 auth_key=integ_key.encode(encoding=u"utf-8"), 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"), tunnel_header=tunnel_out
223 sent_packets = list()
225 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
242 if rx_pkt_recv.haslayer(ICMPv6MLReport2):
243 # read another packet in the queue if the current one is
246 if rx_pkt_recv.haslayer(ICMPv6ND_RA):
247 # read another packet in the queue if the current one is
251 # otherwise process the current packet
255 rx_pkt_recv, ip_layer, rx_src_mac, rx_dst_mac, src_tun, dst_tun, src_ip,
259 rx_ip_pkt = ip_layer(src=dst_ip, dst=src_ip, proto=61) if ip_layer == IP \
260 else ip_layer(src=dst_ip, dst=src_ip)
262 if len(rx_ip_pkt) < (size_limit - 14):
263 rx_ip_pkt[Raw].load += (b"\0" * (size_limit - 14 - len(rx_ip_pkt)))
265 Ether(src=rx_dst_mac, dst=rx_src_mac) / sa_out.encrypt(rx_ip_pkt))
266 rx_txq.send(rx_pkt_send)
269 tx_pkt_recv = tx_rxq.recv(2, ignore=sent_packets)
271 if tx_pkt_recv is None:
272 raise RuntimeError(f"{ip_layer.name} packet Rx timeout")
274 if tx_pkt_recv.haslayer(ICMPv6ND_NS):
275 # read another packet in the queue if the current one is ICMPv6ND_NS
277 if tx_pkt_recv.haslayer(ICMPv6MLReport2):
278 # read another packet in the queue if the current one is
281 if tx_pkt_recv.haslayer(ICMPv6ND_RA):
282 # read another packet in the queue if the current one is
288 check_ip(tx_pkt_recv, ip_layer, tx_dst_mac, tx_src_mac, dst_ip, src_ip)
291 if __name__ == u"__main__":