3 # Copyright (c) 2021 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
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)
100 print(u"Decrypted packet:")
104 if d_pkt[ip_layer].dst != dst_ip:
106 f"Decrypted packet has invalid destination address: "
107 f"{d_pkt[ip_layer].dst} should be: {dst_ip}"
110 if d_pkt[ip_layer].src != src_ip:
112 f"Decrypted packet has invalid source address: "
113 f"{d_pkt[ip_layer].src} should be: {src_ip}"
116 if ip_layer == IP and d_pkt[ip_layer].proto != 61:
118 f"Decrypted packet has invalid IP protocol: "
119 f"{d_pkt[ip_layer].proto} should be: 61"
123 def check_ip(pkt_recv, ip_layer, src_mac, dst_mac, src_ip, dst_ip):
124 """Check received IP/IPv6 packet.
126 :param pkt_recv: Received packet to verify.
127 :param ip_layer: Scapy IP layer.
128 :param src_mac: Source MAC address.
129 :param dst_mac: Destination MAC address.
130 :param src_ip: Source IP/IPv6 address.
131 :param dst_ip: Destination IP/IPv6 address.
132 :type pkt_recv: scapy.Ether
133 :type ip_layer: scapy.layers.inet.IP or scapy.layers.inet6.IPv6
138 :raises RuntimeError: If received packet is invalid.
140 if pkt_recv[Ether].src != src_mac:
142 f"Received frame has invalid source MAC address: "
143 f"{pkt_recv[Ether].src} should be: {src_mac}"
146 if pkt_recv[Ether].dst != dst_mac:
148 f"Received frame has invalid destination MAC address: "
149 f"{pkt_recv[Ether].dst} should be: {dst_mac}"
152 if not pkt_recv.haslayer(ip_layer):
154 f"Not an {ip_layer.__name__} packet received: {pkt_recv!r}"
157 if pkt_recv[ip_layer].dst != dst_ip:
159 f"Received packet has invalid destination address: "
160 f"{pkt_recv[ip_layer.__name__].dst} should be: {dst_ip}"
163 if pkt_recv[ip_layer].src != src_ip:
165 f"Received packet has invalid destination address: "
166 f"{pkt_recv[ip_layer.__name__].dst} should be: {src_ip}"
169 if ip_layer == IP and pkt_recv[ip_layer].proto != 61:
171 f"Received packet has invalid IP protocol: "
172 f"{pkt_recv[ip_layer].proto} should be: 61"
177 """Send and receive IPsec packet."""
179 args = TrafficScriptArg(
181 u"tx_src_mac", u"tx_dst_mac", u"rx_src_mac", u"rx_dst_mac",
182 u"src_ip", u"dst_ip", u"src_tun", u"dst_tun", u"crypto_alg",
183 u"crypto_key", u"integ_alg", u"integ_key", u"l_spi", u"r_spi"
187 tx_txq = TxQueue(args.get_arg(u"tx_if"))
188 tx_rxq = RxQueue(args.get_arg(u"tx_if"))
189 rx_txq = TxQueue(args.get_arg(u"rx_if"))
190 rx_rxq = RxQueue(args.get_arg(u"rx_if"))
192 tx_src_mac = args.get_arg(u"tx_src_mac")
193 tx_dst_mac = args.get_arg(u"tx_dst_mac")
194 rx_src_mac = args.get_arg(u"rx_src_mac")
195 rx_dst_mac = args.get_arg(u"rx_dst_mac")
196 src_ip = args.get_arg(u"src_ip")
197 dst_ip = args.get_arg(u"dst_ip")
198 src_tun = args.get_arg(u"src_tun")
199 dst_tun = args.get_arg(u"dst_tun")
200 crypto_alg = args.get_arg(u"crypto_alg")
201 crypto_key = args.get_arg(u"crypto_key")
202 integ_alg = args.get_arg(u"integ_alg")
203 integ_key = args.get_arg(u"integ_key")
204 l_spi = int(args.get_arg(u"l_spi"))
205 r_spi = int(args.get_arg(u"r_spi"))
207 ip_layer = IP if ip_address(src_ip).version == 4 else IPv6
208 ip_pkt = ip_layer(src=src_ip, dst=dst_ip, proto=61) if ip_layer == IP \
209 else ip_layer(src=src_ip, dst=dst_ip)
211 tunnel_in = ip_layer(src=src_tun, dst=dst_tun)
212 tunnel_out = ip_layer(src=dst_tun, dst=src_tun)
214 sa_in = SecurityAssociation(
215 ESP, spi=l_spi, crypt_algo=crypto_alg,
216 crypt_key=crypto_key.encode(encoding=u"utf-8"), auth_algo=integ_alg,
217 auth_key=integ_key.encode(encoding=u"utf-8"),
218 tunnel_header=tunnel_in
221 sa_out = SecurityAssociation(
222 ESP, spi=r_spi, crypt_algo=crypto_alg,
223 crypt_key=crypto_key.encode(encoding=u"utf-8"), auth_algo=integ_alg,
224 auth_key=integ_key.encode(encoding=u"utf-8"),
225 tunnel_header=tunnel_out
228 sent_packets = list()
229 tx_pkt_send = (Ether(src=tx_src_mac, dst=tx_dst_mac) / ip_pkt)
231 size_limit = 78 if ip_layer == IPv6 else 64
232 if len(tx_pkt_send) < size_limit:
233 tx_pkt_send[Raw].load += (b"\0" * (size_limit - len(tx_pkt_send)))
234 sent_packets.append(tx_pkt_send)
235 tx_txq.send(tx_pkt_send)
238 rx_pkt_recv = rx_rxq.recv(2)
240 if rx_pkt_recv is None:
241 raise RuntimeError(f"{ip_layer.__name__} packet Rx timeout")
243 if rx_pkt_recv.haslayer(ICMPv6ND_NS):
244 # read another packet in the queue if the current one is ICMPv6ND_NS
247 # otherwise process the current packet
251 rx_pkt_recv, ip_layer, rx_src_mac, rx_dst_mac, src_tun, dst_tun, src_ip,
255 ip_pkt = ip_layer(src=dst_ip, dst=src_ip, proto=61) if ip_layer == IP \
256 else ip_layer(src=dst_ip, dst=src_ip)
258 if len(ip_pkt) < (size_limit - 14):
259 ip_pkt[Raw].load += (b"\0" * (size_limit - 14 - len(ip_pkt)))
260 e_pkt = sa_out.encrypt(ip_pkt)
261 rx_pkt_send = (Ether(src=rx_dst_mac, dst=rx_src_mac) /
263 rx_txq.send(rx_pkt_send)
266 tx_pkt_recv = tx_rxq.recv(2, ignore=sent_packets)
268 if tx_pkt_recv is None:
269 raise RuntimeError(f"{ip_layer.__name__} packet Rx timeout")
271 if tx_pkt_recv.haslayer(ICMPv6ND_NS):
272 # read another packet in the queue if the current one is ICMPv6ND_NS
275 # otherwise process the current packet
278 check_ip(tx_pkt_recv, ip_layer, tx_dst_mac, tx_src_mac, dst_ip, src_ip)
283 if __name__ == u"__main__":