IPv4/IPv6 CIDR netmask aware file pattern searcher.
Searches lines from log files by IP address or CIDR mask.
Can also match an IP address search term against firewall
configuration with netmasks.
$ ipgrep 4.3.2.1 example.conf
allow all from 4.3.2.1m255.255.255.0
deny from 4.3.2.1m31