The Photon operating system must log IPv4 packets with impossible addresses.

The presence of "martian" packets (which have impossible addresses) as well as spoofed packets, source-routed packets, and redirects could be a sign of nefarious network activity. Logging these packets enables this activity to be detected.

At the command line, run the following command:

# /sbin/sysctl -a --pattern "net.ipv4.conf.(all|default|eth.*).log_martians"

Expected result:

net.ipv4.conf.all.log_martians = 1 net.ipv4.conf.default.log_martians = 1 net.ipv4.conf.eth0.log_martians = 1

If the output does not match the expected result, this is a finding.

Note: The number of "ethx" lines returned is dependent on the number of interfaces. Every "ethx" entry must be set to "1".

At the command line, run the following command:

# for SETTING in $(/sbin/sysctl -aN --pattern "net.ipv4.conf.(all|default|eth.*).log_martians"); do sed -i -e "/^${SETTING}/d" /etc/sysctl.conf;echo $SETTING=1>>/etc/sysctl.conf; done
# /sbin/sysctl --load