Fail2Ban Integration

Fail2ban scans log files (e.g. /var/log/nginx/error.log) and bans IPs that show malicious signs -- too many password failures, seeking for exploits, etc. Generally Fail2Ban is then used to update firewall rules to reject the IP addresses for a specified amount of time, although any arbitrary other action (e.g. sending an email/notification) could also be configured.

Prerequisites

• Fail2ban installed and configured.

Fail2Ban filter

Go to your filter.d folder in your Fail2Ban install location (/etc/fail2ban/filter.d) and create a file called organizr-auth.conf and add the following:

For Organizr V2 add:

[Definition]
failregex = ","username":"\S+","ip":"<HOST>","auth_type":"error"}*
ignoreregex =

For Organizr V1 add: 

[Definition]
failregex = ","username":"\S+","ip":"<HOST>","auth_type":"bad_auth"}
ignoreregex =

Organizr Jail

Edit the jail.local file in the Fail2Ban directory and add the following: 

[organizr-auth]
enabled = true
port = http,https
filter = organizr-auth
logpath = /var/www/html/db/organizrLoginLog.json
ignoreip = 192.168.1.0/24

• The ignore IP is so that fail2ban won’t ban your local IP. Check out https://www.aelius.com/njh/subnet_sheet.html if you are wondering what your CIDR notation is. Most often it will be /24 (netmask 255.255.255.0)
  To find your netmask run ipconfig /all on windows or ifconfig | grep netmask on linux.

Restart Fail2Ban with sudo service fail2ban restart

Path to Organizr logs

V2: /var/www/html/db/organizrLoginLog.json

V1: /var/www/html/loginLog.json

Docker: /config/db/organizrLoginLog.json

Docker

Because the Organizr container only logs the docker IP addresses e.g 172.17.0.2 you need to add this in the Organizr default nginx site file. Go to \organizr\nginx\site-confs\default and add the following inside the server block:

# get real IP
real_ip_header X-Forwarded-For;
set_real_ip_from 172.17.0.0/16;
real_ip_recursive on;

If you're using organizrtools/organizr-v2 it's already added and you only need to uncomment the set_real_ip_from line. 

Then restart the container: docker restart organizr

Using the linuxserver/letsencrypt container

The Fail2ban filter folder is in /<appdatafolder>/letsencrypt/fail2ban/filter.d

For this to work you need the letsencrypt container to be able to read the organizrLoginLog.json file in the Organizr container.

Mount the Organizr log like this:

-v <path/to/organizr/config/db/>:/organizrlog:ro

And set the log path in the Fail2Ban jail.local file to /organizrlog/organizrLoginLog.json

Banned

The fail2ban.log file should output something like this:

2017-08-08 21:51:13,777 fail2ban.filter [262]: INFO [organizr-auth] Found 5.153.234.107 - 2017-08-08 21:51:12
2017-08-08 21:51:18,811 fail2ban.filter [262]: INFO [organizr-auth] Found 5.153.234.107 - 2017-08-08 21:51:18
2017-08-08 21:51:43,965 fail2ban.filter [262]: INFO [organizr-auth] Ignore 192.168.1.1 by ip
2017-08-08 21:51:51,008 fail2ban.filter [262]: INFO [organizr-auth] Ignore 192.168.1.1 by ip
2017-08-08 21:51:57,045 fail2ban.filter [262]: INFO [organizr-auth] Ignore 192.168.1.1 by ip
2017-08-08 21:52:03,080 fail2ban.filter [262]: INFO [organizr-auth] Ignore 192.168.1.1 by ip
2017-08-08 21:53:25,578 fail2ban.filter [262]: INFO [organizr-auth] Found 104.160.20.131 - 2017-08-08 21:53:24
2017-08-08 21:53:31,617 fail2ban.filter [262]: INFO [organizr-auth] Found 104.160.20.131 - 2017-08-08 21:53:30
2017-08-08 21:53:36,650 fail2ban.filter [262]: INFO [organizr-auth] Found 104.160.20.131 - 2017-08-08 21:53:36
2017-08-08 21:53:42,688 fail2ban.filter [262]: INFO [organizr-auth] Found 104.160.20.131 - 2017-08-08 21:53:41
2017-08-08 21:53:48,726 fail2ban.filter [262]: INFO [organizr-auth] Found 104.160.20.131 - 2017-08-08 21:53:47
2017-08-08 21:53:48,733 fail2ban.actions [262]: NOTICE [organizr-auth] Ban 104.160.20.131

If you managed to ban yourself or a friend banned themself you can run this to unban.

fail2ban-client unban <ip> or docker exec letsencrypt fail2ban-client unban <ip>

Thanks to rix1337 for the fail2ban config: