1# 2# SPDX-License-Identifier: BSD-2-Clause 3# 4# Copyright (c) 2024 Rubicon Communications, LLC (Netgate) 5# 6# Redistribution and use in source and binary forms, with or without 7# modification, are permitted provided that the following conditions 8# are met: 9# 1. Redistributions of source code must retain the above copyright 10# notice, this list of conditions and the following disclaimer. 11# 2. Redistributions in binary form must reproduce the above copyright 12# notice, this list of conditions and the following disclaimer in the 13# documentation and/or other materials provided with the distribution. 14# 15# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25# SUCH DAMAGE. 26 27import pytest 28import subprocess 29import re 30from atf_python.sys.net.tools import ToolsHelper 31from atf_python.sys.net.vnet import VnetTestTemplate 32 33def check(cmd): 34 ps = subprocess.Popen(cmd, shell=True) 35 ret = ps.wait() 36 if ret != 0: 37 raise Exception("Command %s returned %d" % (cmd, ret)) 38 39class TestICMP(VnetTestTemplate): 40 REQUIRED_MODULES = [ "pf" ] 41 TOPOLOGY = { 42 "vnet1": {"ifaces": ["if1"]}, 43 "vnet2": {"ifaces": ["if1", "if2"]}, 44 "vnet3": {"ifaces": ["if2"]}, 45 "if1": {"prefixes4": [("192.0.2.2/24", "192.0.2.1/24")]}, 46 "if2": {"prefixes4": [("198.51.100.1/24", "198.51.100.2/24")]}, 47 } 48 49 def vnet2_handler(self, vnet): 50 ifname = vnet.iface_alias_map["if1"].name 51 if2name = vnet.iface_alias_map["if2"].name 52 53 ToolsHelper.print_output("/sbin/pfctl -e") 54 ToolsHelper.pf_rules([ 55 "set reassemble yes", 56 "block", 57 "pass inet proto icmp icmp-type echoreq", 58 ]) 59 60 ToolsHelper.print_output("/sbin/sysctl net.inet.ip.forwarding=1") 61 ToolsHelper.print_output("/sbin/pfctl -x loud") 62 63 ToolsHelper.print_output("/sbin/ifconfig %s mtu 1492" % if2name) 64 65 def vnet3_handler(self, vnet): 66 # Import in the correct vnet, so at to not confuse Scapy 67 import scapy.all as sp 68 69 ifname = vnet.iface_alias_map["if2"].name 70 ToolsHelper.print_output("/sbin/route add default 198.51.100.1") 71 ToolsHelper.print_output("/sbin/ifconfig %s inet alias 198.51.100.3/24" % ifname) 72 ToolsHelper.print_output("/sbin/ifconfig %s mtu 1492" % ifname) 73 74 def checkfn(packet): 75 icmp = packet.getlayer(sp.ICMP) 76 if not icmp: 77 return False 78 79 if icmp.type != 3: 80 return False 81 82 packet.show() 83 return True 84 85 sp.sniff(iface=ifname, stop_filter=checkfn) 86 vnet.pipe.send("Got ICMP destination unreachable packet") 87 88 @pytest.mark.require_user("root") 89 @pytest.mark.require_progs(["scapy"]) 90 def test_inner_match(self): 91 vnet = self.vnet_map["vnet1"] 92 dst_vnet = self.vnet_map["vnet3"] 93 sendif = vnet.iface_alias_map["if1"].name 94 95 our_mac = ToolsHelper.get_output("/sbin/ifconfig %s ether | awk '/ether/ { print $2; }'" % sendif) 96 dst_mac = re.sub("0a$", "0b", our_mac) 97 98 # Import in the correct vnet, so at to not confuse Scapy 99 import scapy.all as sp 100 101 ToolsHelper.print_output("/sbin/route add default 192.0.2.1") 102 103 # Sanity check 104 check("/sbin/ping -c 1 192.0.2.1") 105 check("/sbin/ping -c 1 198.51.100.1") 106 check("/sbin/ping -c 2 198.51.100.3") 107 108 # Establish a state 109 pkt = sp.Ether(src=our_mac, dst=dst_mac) \ 110 / sp.IP(src="192.0.2.2", dst="198.51.100.2") \ 111 / sp.ICMP(type='echo-request') \ 112 / "PAYLOAD" 113 sp.sendp(pkt, sendif, verbose=False) 114 115 # Now try to pass an ICMP error message piggy-backing on that state, but 116 # use a different source address 117 pkt = sp.Ether(src=our_mac, dst=dst_mac) \ 118 / sp.IP(src="192.0.2.2", dst="198.51.100.3") \ 119 / sp.ICMP(type='dest-unreach') \ 120 / sp.IP(src="198.51.100.2", dst="192.0.2.2") \ 121 / sp.ICMP(type='echo-reply') 122 sp.sendp(pkt, sendif, verbose=False) 123 124 try: 125 rcvd = self.wait_object(dst_vnet.pipe, timeout=1) 126 if rcvd: 127 raise Exception(rcvd) 128 except TimeoutError as e: 129 # We expect the timeout here. It means we didn't get the destination 130 # unreachable packet in vnet3 131 pass 132 133 def check_icmp_echo(self, sp, payload_size): 134 packet = sp.IP(dst="198.51.100.2", flags="DF") \ 135 / sp.ICMP(type='echo-request') \ 136 / sp.raw(bytes.fromhex('f0') * payload_size) 137 138 p = sp.sr1(packet, iface=self.vnet.iface_alias_map["if1"].name, 139 timeout=3) 140 p.show() 141 142 ip = p.getlayer(sp.IP) 143 icmp = p.getlayer(sp.ICMP) 144 assert ip 145 assert icmp 146 147 if payload_size > 1464: 148 # Expect ICMP destination unreachable, fragmentation needed 149 assert ip.src == "192.0.2.1" 150 assert ip.dst == "192.0.2.2" 151 assert icmp.type == 3 # dest-unreach 152 assert icmp.code == 4 153 assert icmp.nexthopmtu == 1492 154 else: 155 # Expect echo reply 156 assert ip.src == "198.51.100.2" 157 assert ip.dst == "192.0.2.2" 158 assert icmp.type == 0 # "echo-reply" 159 assert icmp.code == 0 160 161 return 162 163 @pytest.mark.require_user("root") 164 @pytest.mark.require_progs(["scapy"]) 165 def test_fragmentation_needed(self): 166 ToolsHelper.print_output("/sbin/route add default 192.0.2.1") 167 168 ToolsHelper.print_output("/sbin/ping -c 1 198.51.100.2") 169 ToolsHelper.print_output("/sbin/ping -c 1 -D -s 1472 198.51.100.2") 170 171 # Import in the correct vnet, so at to not confuse Scapy 172 import scapy.all as sp 173 174 self.check_icmp_echo(sp, 128) 175 self.check_icmp_echo(sp, 1464) 176 self.check_icmp_echo(sp, 1468) 177