This is a one-file PHP script to anonymize an IP address on a line given through STDIN. You can for example use it as a pipe for web server logs, so that no private IP addresses are recorded.
Both IPv4 and IPv6 addresses are supported. Addresses are anonymized to their network ID.
The default settings anonymize an IP address to a /24 subnet (IPv4) or a /48 subnet (IPv6), but these can be customized.
For instance, the IPv4 address 192.168.178.123 is anonymized by default to 192.168.178.0.
The IPv6 address 2001:0db8:85a3:08d3:1319:8a2e:0370:7347 is anonymized by default to 2001:0db8:85a3::.
The IP address is expected to occur on the beginning of the line. A delimiter can can be given as first argument. The output will be written to a file when given as second argument.
$ log='2001:0db8:85a3:08d3:1319:8a2e:0370:7347 - - [16/May/2018:06:30:01 +0200] "HEAD / HTTP/1.1" 301 235 "-"
192.168.2.123 - - [16/May/2018:06:30:02 +0200] "HEAD / HTTP/1.1" 301 235 "-"'
$ echo -n "${log}" | ./anonymizer.php ' '; echo
> 2001:db8:85a3:: - - [16/May/2018:06:30:01 +0200] "HEAD / HTTP/1.1" 301 235 "-"
> 192.168.2.0 - - [16/May/2018:06:30:02 +0200] "HEAD / HTTP/1.1" 301 235 "-"
This library is licensed under the MIT License. See the LICENSE file for the full license.