[arch-general] HTTP spam from China - CIDR compacting tool

[Juha Kankare]

On 26/02/2019 20:11, Genes Lists via arch-general wrote:
>   Just an FYI if you pull cidr blocks by country, either doing it
> yourself directly from arin et al or by using someone elses list like
> ipdeny.com the CIDR blocks are not necessarily compacted.
>
>   i.e. it is often not the most minimal CIDR representation. I use is
> this little python script, which works on list of CIDR blocks of IPV4 or
> IPV6, to compact the list of cidr blocks.  I feed the output compacted
> CIDR blocks to the firewall ipset script.
>
>
> In case anyone finds this useful here is my CidrMerge.py :
>
> UseageL
>
> ----- cut here -----
> #!/usr/bin/python
> #
> # Read from  stdin a list of cidr blocks and compacts them if possible
> # Resulting compacted CIDR blocks are written to stdout.
> # Works on any file with IPV4 or IPV6 cidr blocks.
> #
> # Usage : CidrMerge.py < file
> #
> # Gene C.
> #
> # 20180503
> #
>
> import sys
> import netaddr
>
>
> def main():
>      num_args = len(sys.argv)
>
>      #
>      # Open file - read one line at a time and output
>      #
>
>      lines=sys.stdin.readlines()
>      if len(lines) == 1:
>          lines = lines[0].split()
>
>      #
>      # create merged set of entire input lines
>      #
>      set1 = netaddr.IPSet(lines)
>
>       #
>       # Write them out
>       #
>      for cidr in set1.iter_cidrs() :
>          print (cidr)
>
>      return
>
> # -----------------------------------------------------
> if __name__ == '__main__':
>          main()
>
> #
> # -------------------- All Done ------------------------

My current script is just pulling cn.zone from ipdeny.com. This looks 
super useful, I'm saving it. Thank you dude!

-- 
Regards, Juha Kankare