1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
|
#
# SPDX-License-Identifier: BSD-2-Clause
#
# Copyright (c) 2024 Rubicon Communications, LLC (Netgate)
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
import pytest
import subprocess
import re
from atf_python.sys.net.tools import ToolsHelper
from atf_python.sys.net.vnet import VnetTestTemplate
def check(cmd):
ps = subprocess.Popen(cmd, shell=True)
ret = ps.wait()
if ret != 0:
raise Exception("Command %s returned %d" % (cmd, ret))
class TestICMP(VnetTestTemplate):
REQUIRED_MODULES = [ "pf" ]
TOPOLOGY = {
"vnet1": {"ifaces": ["if1"]},
"vnet2": {"ifaces": ["if1", "if2"]},
"vnet3": {"ifaces": ["if2"]},
"if1": {"prefixes4": [("192.0.2.2/24", "192.0.2.1/24")]},
"if2": {"prefixes4": [("198.51.100.1/24", "198.51.100.2/24")]},
}
def vnet2_handler(self, vnet):
ifname = vnet.iface_alias_map["if1"].name
if2name = vnet.iface_alias_map["if2"].name
ToolsHelper.print_output("/sbin/pfctl -e")
ToolsHelper.pf_rules([
"set reassemble yes",
"set state-policy if-bound",
"block",
"pass inet proto icmp icmp-type echoreq",
])
ToolsHelper.print_output("/sbin/sysctl net.inet.ip.forwarding=1")
ToolsHelper.print_output("/sbin/pfctl -x loud")
ToolsHelper.print_output("/sbin/ifconfig %s mtu 1492" % if2name)
def vnet3_handler(self, vnet):
# Import in the correct vnet, so at to not confuse Scapy
import scapy.all as sp
ifname = vnet.iface_alias_map["if2"].name
ToolsHelper.print_output("/sbin/route add default 198.51.100.1")
ToolsHelper.print_output("/sbin/ifconfig %s inet alias 198.51.100.3/24" % ifname)
ToolsHelper.print_output("/sbin/ifconfig %s mtu 1492" % ifname)
def checkfn(packet):
icmp = packet.getlayer(sp.ICMP)
if not icmp:
return False
if icmp.type != 3:
return False
packet.show()
return True
sp.sniff(iface=ifname, stop_filter=checkfn)
vnet.pipe.send("Got ICMP destination unreachable packet")
@pytest.mark.require_user("root")
@pytest.mark.require_progs(["scapy"])
def test_inner_match(self):
vnet = self.vnet_map["vnet1"]
dst_vnet = self.vnet_map["vnet3"]
sendif = vnet.iface_alias_map["if1"]
our_mac = sendif.ether
dst_mac = sendif.epairb.ether
# Import in the correct vnet, so at to not confuse Scapy
import scapy.all as sp
ToolsHelper.print_output("/sbin/route add default 192.0.2.1")
# Sanity check
check("/sbin/ping -c 1 192.0.2.1")
check("/sbin/ping -c 1 198.51.100.1")
check("/sbin/ping -c 2 198.51.100.3")
# Establish a state
pkt = sp.Ether(src=our_mac, dst=dst_mac) \
/ sp.IP(src="192.0.2.2", dst="198.51.100.2") \
/ sp.ICMP(type='echo-request') \
/ "PAYLOAD"
sp.sendp(pkt, sendif.name, verbose=False)
# Now try to pass an ICMP error message piggy-backing on that state, but
# use a different source address
pkt = sp.Ether(src=our_mac, dst=dst_mac) \
/ sp.IP(src="192.0.2.2", dst="198.51.100.3") \
/ sp.ICMP(type='dest-unreach') \
/ sp.IP(src="198.51.100.2", dst="192.0.2.2") \
/ sp.ICMP(type='echo-reply')
sp.sendp(pkt, sendif.name, verbose=False)
try:
rcvd = self.wait_object(dst_vnet.pipe, timeout=1)
if rcvd:
raise Exception(rcvd)
except TimeoutError as e:
# We expect the timeout here. It means we didn't get the destination
# unreachable packet in vnet3
pass
def check_icmp_echo(self, sp, payload_size):
packet = sp.IP(dst="198.51.100.2", flags="DF") \
/ sp.ICMP(type='echo-request') \
/ sp.raw(bytes.fromhex('f0') * payload_size)
p = sp.sr1(packet, timeout=3)
p.show()
ip = p.getlayer(sp.IP)
icmp = p.getlayer(sp.ICMP)
assert ip
assert icmp
if payload_size > 1464:
# Expect ICMP destination unreachable, fragmentation needed
assert ip.src == "192.0.2.1"
assert ip.dst == "192.0.2.2"
assert icmp.type == 3 # dest-unreach
assert icmp.code == 4
assert icmp.nexthopmtu == 1492
else:
# Expect echo reply
assert ip.src == "198.51.100.2"
assert ip.dst == "192.0.2.2"
assert icmp.type == 0 # "echo-reply"
assert icmp.code == 0
return
@pytest.mark.require_user("root")
@pytest.mark.require_progs(["scapy"])
def test_fragmentation_needed(self):
ToolsHelper.print_output("/sbin/route add default 192.0.2.1")
ToolsHelper.print_output("/sbin/ping -c 1 198.51.100.2")
ToolsHelper.print_output("/sbin/ping -c 1 -D -s 1472 198.51.100.2")
# Import in the correct vnet, so at to not confuse Scapy
import scapy.all as sp
self.check_icmp_echo(sp, 128)
self.check_icmp_echo(sp, 1464)
self.check_icmp_echo(sp, 1468)
@pytest.mark.require_user("root")
@pytest.mark.require_progs(["scapy"])
def test_truncated_opts(self):
ToolsHelper.print_output("/sbin/route add default 192.0.2.1")
# Import in the correct vnet, so at to not confuse Scapy
import scapy.all as sp
packet = sp.IP(dst="198.51.100.2", flags="DF") \
/ sp.ICMP(type='dest-unreach', length=108) \
/ sp.IP(src="198.51.100.2", dst="192.0.2.2", len=1000, \
ihl=(120 >> 2), options=[ \
sp.IPOption_Security(length=100)])
packet.show()
sp.sr1(packet, timeout=3)
class TestICMP_NAT(VnetTestTemplate):
REQUIRED_MODULES = [ "pf" ]
TOPOLOGY = {
"vnet1": {"ifaces": ["if1"]},
"vnet2": {"ifaces": ["if1", "if2"]},
"vnet3": {"ifaces": ["if2"]},
"if1": {"prefixes4": [("192.0.2.2/24", "192.0.2.1/24")]},
"if2": {"prefixes4": [("198.51.100.1/24", "198.51.100.2/24")]},
}
def vnet2_handler(self, vnet):
ifname = vnet.iface_alias_map["if1"].name
if2name = vnet.iface_alias_map["if2"].name
ToolsHelper.print_output("/sbin/pfctl -e")
ToolsHelper.pf_rules([
"set reassemble yes",
"set state-policy if-bound",
"nat on %s inet from 192.0.2.0/24 to any -> (%s)" % (if2name, if2name),
"block",
"pass inet proto icmp icmp-type echoreq",
])
ToolsHelper.print_output("/sbin/sysctl net.inet.ip.forwarding=1")
ToolsHelper.print_output("/sbin/pfctl -x loud")
def vnet3_handler(self, vnet):
ifname = vnet.iface_alias_map["if2"].name
ToolsHelper.print_output("/sbin/ifconfig %s inet alias 198.51.100.3/24" % ifname)
@pytest.mark.require_user("root")
@pytest.mark.require_progs(["scapy"])
def test_id_conflict(self):
"""
Test ICMP echo requests with the same ID from different clients.
Windows does this, and it can confuse pf.
"""
ifname = self.vnet.iface_alias_map["if1"].name
ToolsHelper.print_output("/sbin/route add default 192.0.2.1")
ToolsHelper.print_output("/sbin/ifconfig %s inet alias 192.0.2.3/24" % ifname)
ToolsHelper.print_output("/sbin/ping -c 1 192.0.2.1")
ToolsHelper.print_output("/sbin/ping -c 1 198.51.100.1")
ToolsHelper.print_output("/sbin/ping -c 1 198.51.100.2")
ToolsHelper.print_output("/sbin/ping -c 1 198.51.100.3")
# Import in the correct vnet, so at to not confuse Scapy
import scapy.all as sp
# Address one
packet = sp.IP(src="192.0.2.2", dst="198.51.100.2", flags="DF") \
/ sp.ICMP(type='echo-request', id=42) \
/ sp.raw(bytes.fromhex('f0') * 16)
p = sp.sr1(packet, timeout=3)
p.show()
ip = p.getlayer(sp.IP)
icmp = p.getlayer(sp.ICMP)
assert ip
assert icmp
assert ip.dst == "192.0.2.2"
assert icmp.id == 42
# Address one
packet = sp.IP(src="192.0.2.3", dst="198.51.100.2", flags="DF") \
/ sp.ICMP(type='echo-request', id=42) \
/ sp.raw(bytes.fromhex('f0') * 16)
p = sp.sr1(packet, timeout=3)
p.show()
ip = p.getlayer(sp.IP)
icmp = p.getlayer(sp.ICMP)
assert ip
assert icmp
assert ip.dst == "192.0.2.3"
assert icmp.id == 42
|
