NAME¶
grepcidr — Filter IP addresses matching IPv4 CIDR/network specification
SYNOPSIS¶
grepcidr [
-V] [
-c] [
-v] [
-e pattern
| -f file]
DESCRIPTION¶
This manual page documents briefly the
grepcidr command.
This manual page was written for the
Debian distribution because the
original program does not have a manual page.
grepcidr can be used to filter a list of IP addresses against one or more
Classless Inter-Domain Routing (CIDR) specifications, or arbitrary networks
specified by an address range. As with grep, there are options to invert
matching and load patterns from a file. grepcidr is capable of comparing
thousands or even millions of IPs to networks with little memory usage and in
reasonable computation time.
OPTIONS¶
- -V
- Show software version
- -c
- Display count of the matching lines, instead of showing the lines
- -v
- Invert the sense of matching, to select non-matching IP addresses
- -e
- Specify pattern(s) on command-line
- -f
- Obtain CIDR and range pattern(s) from file
EXAMPLES¶
grepcidr -f ournetworks blocklist > abuse.log
Find our customers that show up in blocklists
grepcidr 127.0.0.0/8 iplog
Searches for any localnet IP addresses inside the iplog file
grepcidr "192.168.0.1-192.168.10.13" iplog
Searches for IPs matching indicated range in the iplog file
script | grepcidr -vf whitelist >
blacklist
Create a blacklist, with whitelisted networks removed (inverse)
grepcidr -f list1 list2
Cross-reference two lists, outputs IPs common to both lists
AUTHOR¶
This manual page was written by Ryan Finnie ryan@finnie.org for the
Debian system (but may be used by others). Permission is granted to
copy, distribute and/or modify this document under the terms of the GNU
General Public License, Version 2 any later version published by the Free
Software Foundation.
On Debian systems, the complete text of the GNU General Public License can be
found in /usr/share/common-licenses/GPL.