This series implements NAT networks support for FreeBSD using the Packet
Filter (pf) firewall.
The commit messages provide high-level details and limitations of the
current implementation, and I'll use this cover letter to provide some
more technical details and describe testing I have performed for this
change.
Libvirt FreeBSD/pf NAT testing
For two networks:
virsh # net-dumpxml default
<network>
<name>default</name>
<uuid>68cd5419-9fda-4cf0-9ac6-2eb9c1ba41ed</uuid>
<forward mode='nat'>
<nat>
<port start='1024' end='65535'/>
</nat>
</forward>
<bridge name='virbr0' stp='on' delay='0'/>
<mac address='52:54:00:db:0e:e5'/>
<ip address='192.168.122.1' netmask='255.255.255.0'>
<dhcp>
<range start='192.168.122.2' end='192.168.122.254'/>
</dhcp>
</ip>
</network>
virsh # net-dumpxml natnet
<network>
<name>natnet</name>
<uuid>d3c59659-3ceb-4482-a625-1f839a54429c</uuid>
<forward mode='nat'>
<nat>
<port start='1024' end='65535'/>
</nat>
</forward>
<bridge name='virbr1' stp='on' delay='0'/>
<mac address='52:54:00:0a:fc:1d'/>
<ip address='10.0.100.1' netmask='255.255.255.0'>
<dhcp>
<range start='10.0.100.2' end='10.0.100.254'/>
</dhcp>
</ip>
</network>
virsh #
The following rules are generated:
$ sudo pfctl -a '*' -sn
nat-anchor "libvirt/*" all {
nat-anchor "default" all {
nat pass on re0 inet from 192.168.122.0/24 to <natdst> -> (re0) port
1024:65535 round-robin
}
nat-anchor "natnet" all {
nat pass on re0 inet from 10.0.100.0/24 to <natdst> -> (re0) port
1024:65535 round-robin
}
}
$
$ sudo pfctl -a 'libvirt/default' -t natdst -T show
0.0.0.0/0
!192.168.122.0/24
!224.0.0.0/24
!255.255.255.255
$ sudo pfctl -a 'libvirt/natnet' -t natdst -T show
0.0.0.0/0
!10.0.100.0/24
!224.0.0.0/24
!255.255.255.255
$
$ sudo pfctl -a '*' -sr
scrub all fragment reassemble
anchor "libvirt/*" all {
anchor "default" all {
pass quick on virbr0 inet from 192.168.122.0/24 to 192.168.122.0/24
flags S/SA keep state
pass quick on virbr0 inet from 192.168.122.0/24 to 224.0.0.0/24
flags S/SA keep state
pass quick on virbr0 inet from 192.168.122.0/24 to 255.255.255.255
flags S/SA keep state
block drop on virbr0 all
}
anchor "natnet" all {
pass quick on virbr1 inet from 10.0.100.0/24 to 10.0.100.0/24 flags
S/SA keep state
pass quick on virbr1 inet from 10.0.100.0/24 to 224.0.0.0/24 flags
S/SA keep state
pass quick on virbr1 inet from 10.0.100.0/24 to 255.255.255.255
flags S/SA keep state
block drop on virbr1 all
}
}
pass all flags S/SA keep state
$
Create two guests attached to the "default" network, vmA and vmB.
vmA $ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group
default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: enp0s4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP
group default qlen 1000
link/ether 52:54:00:67:eb:de brd ff:ff:ff:ff:ff:ff
inet 192.168.122.92/24 brd 192.168.122.255 scope global dynamic
noprefixroute enp0s4
valid_lft 1082sec preferred_lft 1082sec
inet6 fe80::5054:ff:fe67:ebde/64 scope link noprefixroute
valid_lft forever preferred_lft forever
vmA $
vmB $ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group
default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: enp0s4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP
group default qlen 1000
link/ether 52:54:00:d2:8b:41 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.154/24 metric 100 brd 192.168.122.255 scope global dynamic
enp0s4
valid_lft 1040sec preferred_lft 1040sec
inet6 fe80::5054:ff:fed2:8b41/64 scope link
valid_lft forever preferred_lft forever
vmB $
Test NAT rules:
vmA $ ping -c 3 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=57 time=14.7 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=57 time=10.7 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=57 time=10.1 ms
--- 8.8.8.8 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2006ms
rtt min/avg/max/mdev = 10.099/11.835/14.710/2.047 ms
vmA $
vmB $ ping -c 3 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=57 time=15.1 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=57 time=11.0 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=57 time=10.4 ms
--- 8.8.8.8 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2006ms
rtt min/avg/max/mdev = 10.434/12.198/15.113/2.075 ms
vmB $
vmA $ curl wttr.in/?0Q
Fog
_ - _ - _ - +4(1) °C
_ - _ - _ ↙ 11 km/h
_ - _ - _ - 0 km
0.0 mm
vmA $
vmB $ curl wttr.in/?0Q
Fog
_ - _ - _ - +4(1) °C
_ - _ - _ ↙ 11 km/h
_ - _ - _ - 0 km
0.0 mm
vmB $
Inter-VM connectivity:
vmA $ ping -c 3 192.168.122.154
PING 192.168.122.154 (192.168.122.154) 56(84) bytes of data.
64 bytes from 192.168.122.154: icmp_seq=1 ttl=64 time=0.253 ms
64 bytes from 192.168.122.154: icmp_seq=2 ttl=64 time=0.226 ms
64 bytes from 192.168.122.154: icmp_seq=3 ttl=64 time=0.269 ms
--- 192.168.122.154 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2042ms
rtt min/avg/max/mdev = 0.226/0.249/0.269/0.017 ms
vmA $
vmA $ ssh 192.168.122.154 uname
novel@192.168.122.154's password:
Linux
vmA $
Multicast test:
vmA $ iperf -s -u -B 224.0.0.1 -i 1
------------------------------------------------------------
Server listening on UDP port 5001
Joining multicast group 224.0.0.1
Server set to single client traffic mode (per multicast receive)
UDP buffer size: 208 KByte (default)
------------------------------------------------------------
[ 1] local 224.0.0.1 port 5001 connected with 192.168.122.154 port
36963
[ ID] Interval Transfer Bandwidth Jitter Lost/Total
Datagrams
[ 1] 0.00-1.00 sec 131 KBytes 1.07 Mbits/sec 0.030 ms 0/91 (0%)
[ 1] 1.00-2.00 sec 128 KBytes 1.05 Mbits/sec 0.022 ms 0/89 (0%)
[ 1] 2.00-3.00 sec 128 KBytes 1.05 Mbits/sec 0.021 ms 0/89 (0%)
[ 1] 0.00-3.02 sec 389 KBytes 1.06 Mbits/sec 0.026 ms 0/271 (0%)
vmB $ iperf -c 224.0.0.1 -u -T 32 -t 3 -i 1
------------------------------------------------------------
Client connecting to 224.0.0.1, UDP port 5001
Sending 1470 byte datagrams, IPG target: 11215.21 us (kalman adjust)
UDP buffer size: 208 KByte (default)
------------------------------------------------------------
[ 1] local 192.168.122.154 port 36963 connected with 224.0.0.1 port
5001
[ ID] Interval Transfer Bandwidth
[ 1] 0.0000-1.0000 sec 131 KBytes 1.07 Mbits/sec
[ 1] 1.0000-2.0000 sec 128 KBytes 1.05 Mbits/sec
[ 1] 2.0000-3.0000 sec 128 KBytes 1.05 Mbits/sec
[ 1] 0.0000-3.0173 sec 389 KBytes 1.06 Mbits/sec
[ 1] Sent 272 datagrams
vmB $
Broadcast test:
vmA $ sudo sysctl -w net.ipv4.icmp_echo_ignore_broadcasts=0
net.ipv4.icmp_echo_ignore_broadcasts = 0
vmA $
vmB $ sudo sysctl -w net.ipv4.icmp_echo_ignore_broadcasts=0
net.ipv4.icmp_echo_ignore_broadcasts = 0
vmB $
host $ ping 192.168.122.255
PING 192.168.122.255 (192.168.122.255): 56 data bytes
64 bytes from 192.168.122.154: icmp_seq=0 ttl=64 time=0.199 ms
64 bytes from 192.168.122.92: icmp_seq=0 ttl=64 time=0.227 ms (DUP!)
64 bytes from 192.168.122.154: icmp_seq=1 ttl=64 time=0.209 ms
64 bytes from 192.168.122.92: icmp_seq=1 ttl=64 time=0.235 ms (DUP!)
^C
--- 192.168.122.255 ping statistics ---
2 packets transmitted, 2 packets received, +2 duplicates, 0.0% packet
loss
round-trip min/avg/max/stddev = 0.199/0.218/0.235/0.014 ms
This testing does not cover any negative scenarios which are probably
not that important at this point.
Roman Bogorodskiy (2):
network: bridge_driver: add BSD implementation
network: introduce Packet Filter firewall backend
meson.build | 2 +
po/POTFILES | 2 +
src/network/bridge_driver_bsd.c | 107 +++++++++
src/network/bridge_driver_conf.c | 8 +
src/network/bridge_driver_linux.c | 2 +
src/network/bridge_driver_platform.c | 2 +
src/network/meson.build | 1 +
src/network/network_pf.c | 327 +++++++++++++++++++++++++++
src/network/network_pf.h | 26 +++
src/util/virfirewall.c | 4 +-
src/util/virfirewall.h | 2 +
11 files changed, 482 insertions(+), 1 deletion(-)
create mode 100644 src/network/bridge_driver_bsd.c
create mode 100644 src/network/network_pf.c
create mode 100644 src/network/network_pf.h
--
2.49.0
