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How to Dynamically Ban Malicious IP's using IPSet (adamm version)

Discussion in 'Asuswrt-Merlin' started by Adamm, Apr 16, 2014.

  1. Adamm

    Adamm Senior Member

    Joined:
    Mar 26, 2013
    Messages:
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    UPDATED 25/04/2017

    Currently this script is only supported for ARM based routers (AC56U/AC68U) as they run a different version of IPTables. This most likely supports newer ARM models with an updated kernel but I have no way to test.


    Below you will find a script that automates the process of banning/whitelisting IP's you desire. The main reason for this script was to automatically and permanently ban IP's that show up in the routers syslog under the prefix "DROP *".

    This is just another small line of defence, but it also adds useful IP banning functionality using IPSet which has almost no performance impact on the router when banning hundreds of thousands of IP's.



    INSTALLATION;


    1. Create the file /jffs/scripts/firewall (using a text editor like nano) and copy the code from the linked post.

    2. Create the file /jffs/scripts/firewall-start from again the code in the linked post.

    3. Chmod both files so they are executable.

    Code:
    chmod +x /jffs/scripts/firewall
    chmod +x /jffs/scripts/firewall-start
    Reboot the router. If this was successful, in the router syslog you should see similar lines

    Code:
    Apr 22 18:42:50 Firewall: [IP Banning Started] ... ... ...
    Apr 22 18:42:51 Firewall: [Complete] 5670 IPs currently banned. 54 New IP's Banned. [1s]


    USAGE;

    Usage of this script is fairly straight forward and each function is separated and described in the file provided. Each command can be executed from SSH using the syntax

    Code:
    sh /jffs/scripts/firewall *commandhere*


    WHITELISTING;

    By default, 192.168.1.0/24 & the value of "nvram get lan_ipaddr"/24 will be whitelisted to prevent accidentally locking yourself out from the routers GUI. Please note if you wish to whitelist other IP's the script currently is defaulted to only accept blocks of /24 from a specified file location when using the "sh /jffs/scripts/firewall whitelist" command.



    OTHER FUNCTIONS;

    Code:
    ##############################
    ###       Commands         ###
    ##############################
    "unban"         # <-- Remove Single IP From Blacklist
    "unbanall"      # <-- Unbans All IPs In Blacklist
    "removeall"     # <-- Remove All Entries From Blacklist
    "save"          # <-- Save Blacklists to /jffs/scripts/ipset.txt
    "ban"           # <-- Adds Entry To Blacklist
    "country"       # <-- Adds entire country to blacklist
    "bancountry"    # <-- Bans specified countries in this file
    "banmalware"    # <-- Bans various malware domains
    "whitelist"     # <-- Add IPs from path to Whitelist
    "new"           # <-- Create new IPSet Blacklist
    ##############################
    

    Some features include indivudal IP banning, pre-defined country banning, banning specicified countries, banning some known malware lists and easily importing other IPSets.


    I am open to any suggestions for modifying this script as this version is specifically for the community as there have been lots of requests for this type of functionality. Please note this script will only work on RMerlin based firmwares with JFFS enabled. Hope others can put it to good use :cool:
     
    Last edited: Apr 24, 2017 at 10:15 AM
    a_lunatic and ryzhov_al like this.
  2. thelonelycoder

    thelonelycoder Part of the Furniture

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    That evolved quickly and nicely! Thank you.
    I use differing LAN settings and others may too.
    I would have to download the sript manually first and install it that way.
    To help others you could insert a direct download link or post the content of the files in your first post.
     
  3. Adamm

    Adamm Senior Member

    Joined:
    Mar 26, 2013
    Messages:
    324
    EDIT;

    Updated 12/04/2017

    /jffs/scripts/firewall

    Part 1

    Part 2

    /jffs/scripts/firewall-start

    Code:
    #!/bin/sh
    
    echo "0 * * * * /jffs/scripts/firewall save" > /var/spool/cron/crontabs/admin
    [ -n "`pidof crond`" ] && killall -q crond
    
    sleep 5
    crond
    sh /jffs/scripts/firewall
    
    Rember to "chmod +x" files after creating them so they can be executed.
     
    Last edited: Apr 12, 2017
  4. jernau

    jernau Occasional Visitor

    Joined:
    May 30, 2013
    Messages:
    41
    Unfortunately this script doesn't work for me, I just get loads of errors stating that the --match-set argument is not available in the version of iptables installed;

    iptables v1.3.8: Unknown arg `--match-set'

    I'm running 374.41 Beta 1

    Also the firewall.sh script as downloaded appears to be in DOS format i.e. includes windows linefeeds (^M) so wouldn't run until I ran dos2unix on another machine against the file.
     
  5. Adamm

    Adamm Senior Member

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    324
    Thanks for pointing that out, for some reason my encoding settings seem to hate me and constantly change back (lol). Fixed and tested it to make sure it works.
     
  6. shooter40sw

    shooter40sw Senior Member

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    Mar 3, 2013
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    233
    Hi guys, I already have donwload manager installed, and no planes de uninstall it, or install entware, also have active ssh brute force prevention on the admin page, can I use this script?, I also use a "wierd" :D LAN setup! x.x.x.x/27 thanks
     
  7. Adamm

    Adamm Senior Member

    Joined:
    Mar 26, 2013
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    324
    Yes this will also work with DLM installed, the requirement is so that optware is installed which happens during the DLM setup process.

    This script also should not interfere with any settings so go wild. The script also automatically detects your lan setup on start-up and whitelist's it (using the lan_ipaddr var)

    Hope this helps.
     
  8. jernau

    jernau Occasional Visitor

    Joined:
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    41
    Does this script only work on certain Merlin versions as I mentioned before I keep getting the following error when running the script;

    iptables v1.3.8: Unknown arg `--match-set'
     
  9. Adamm

    Adamm Senior Member

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    What router are you running and which firmware? Your IPTables is out of date compared to the latest release which the script is based on.

    [email protected]:/tmp/home/root# iptables -V
    iptables v1.4.14

    [email protected]:/tmp/home/root# ipset -V
    ipset v4.5, protocol version 4.
    Kernel module protocol version 4.


    Edit; Okay so just realized the AC66U for whatever reason is based on an older IPTables version. For now support is limited to the AC56U and AC68U. Sorry about that.
     
    Last edited: Apr 16, 2014
  10. octopus

    octopus Very Senior Member

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    Use: -m set --match-set
     
    Last edited: Nov 7, 2016
  11. Adamm

    Adamm Senior Member

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    I will eventually make the script dynamically adjust the IPTables syntax based on the router model, currently the N56U/AC66U/AC68U all run different versions of IPTables and IPSet which makes things painful as I'm maintaining 3 different scripts that do the same thing. I'll get around to it sooner or later.
     
  12. wbennett77

    wbennett77 Regular Contributor

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    Hey Adamm,

    Thanks for sharing your work with us. I am using your script and being this is the first time I have ever used SSH and I have one question. I just upgraded the firmare to Merlins final .41 and I wanted to know if this area gets overwritten during the upgrade. I don't see the "starting ...." but I do see this:
    Apr 19 09:45:52 Firewall: [Complete] 0 IPs currently banned. 0 New IP's Banned.
    I am assuming that this means that it didn't get overwritten but being a rookie in this area just need to know for sure.

    Cheers!
     
  13. Adamm

    Adamm Senior Member

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    Looks like its working fine, if you see anything like that in the syslog you can confirm its been executed.
     
  14. wbennett77

    wbennett77 Regular Contributor

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    Thanks Adamm!
     
  15. idolza

    idolza New Around Here

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    @Adamm thank you so much.

    Managed to get it working and its been doing its work for me :

    Apr 21 15:11:38 Firewall: [IP Banning Started] ... ... ...
    Apr 21 15:11:39 Firewall: [Complete] 159 IPs currently banned. 2 New IP's Banned.

    Having teenagers on the network, who aren't as careful - this also helps along with all the other measures I've put in place.
     
  16. wbennett77

    wbennett77 Regular Contributor

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    That's a lot of banned IPs. Did you add anything to the defaults such as additional countries?
    Cheers!

    Sent from my Galaxy S4 using Tapatalk
     
  17. sinshiva

    sinshiva Very Senior Member

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    sometimes JFFS is overwritten during upgrades so it would definitely be wise to backup from time to time.
     
  18. wbennett77

    wbennett77 Regular Contributor

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    One possibly strange question (rookie) but do I have to leave SSH enabled on the router for this to run correctly? The reason I ask is because as soon as I enable SSH the router log showed this but nothing before being enabled:
    Maybe it's just a coincidence?

    Cheers!
     
  19. Adamm

    Adamm Senior Member

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    I believe your question was answered on IRC but for convience of others, no SSH being enabled is not a requirement but it is required to install the script (that or Telnet).

    And for clarification, the "firewall-start" script is how the firewall addition is initiated on boot (or firewall restart), along with setting up two conjobs that save the IP list and back it up.


    For others to see the scripts effectiveness, here's my firewalls results after a week.

     
    Last edited: Apr 22, 2014
  20. wbennett77

    wbennett77 Regular Contributor

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    Good morning,

    Yes, after writing here I went directly to IRC and got the answer I was looking for.

    A couple other things.....how do I get an update as to how many ip's have currently been banned and where would I go to get a country list that works with your script.

    Thanks again!

    Cheers!
     

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