Fail2ban plugin for traefik

This plugin is a small implementation of a fail2ban instance as a middleware plugin for Traefik.

Configuration

Whitelist

You can whitelist some IP using this:

testData:
  whitelist:
    files:
      - "tests/test-ipfile.txt"
    ip:
      - "::1"
      - "127.0.0.1"

Where you can use some IP in an array of files or directly in the configuration.

Blacklist

Like whitelist, you can blacklist some IP using this:

testData:
  blacklist:
    files:
      - "tests/test-ipfile.txt"
    ip:
      - "::1"
      - "127.0.0.1"

Where you can use some IP in an array of files or directly in the configuration.

LogLevel

In order to help you and us when building and using the plugin, we added some logs on stdout. You can choose the level of logging with this:

testData:
  logLevel: "INFO"

There is 3 level of logging :

`NONE`

The plugin will not output any logs.

INFO[0000] Configuration loaded from file: ./traefik.yml

`INFO`

Configuration informations will be displayed.

INFO[0000] Configuration loaded from file: ./traefik.yml
INFO: Fail2Ban: restricted.go:51: Whitelisted: '127.0.0.2/32'
INFO: Fail2Ban: restricted.go:51: Blacklisted: '127.0.0.3/32'
INFO: Fail2Ban: restricted.go:51: Bantime: 3h0m0s
INFO: Fail2Ban: restricted.go:51: Findtime: 3h0m0s
INFO: Fail2Ban: restricted.go:51: FailToBan Rules : '{Xbantime:3h0m0s Xfindtime:3h0m0s Xurlregexp:[localhost:5000/whoami] Xmaxretry:4 Xenabled:true}'
INFO: Fail2Ban: restricted.go:52: Plugin: FailToBan is up and running
INFO: Fail2Ban: restricted.go:51: Whitelisted: '127.0.0.2/32'
INFO: Fail2Ban: restricted.go:51: Blacklisted: '127.0.0.3/32'
INFO: Fail2Ban: restricted.go:51: Bantime: 3h0m0s
INFO: Fail2Ban: restricted.go:51: Findtime: 3h0m0s
INFO: Fail2Ban: restricted.go:51: FailToBan Rules : '{Xbantime:3h0m0s Xfindtime:3h0m0s Xurlregexp:[localhost:5000/whoami] Xmaxretry:4 Xenabled:true}'
INFO: Fail2Ban: restricted.go:52: Plugin: FailToBan is up and running

`DEBUG`

Every event will be logged.

Warning, all IPs will be prompted in clear text with this option.

INFO[0000] Configuration loaded from file: ./traefik.yml
INFO: Fail2Ban: restricted.go:51: Whitelisted: '127.0.0.2/32'
INFO: Fail2Ban: restricted.go:51: Blacklisted: '127.0.0.3/32'
INFO: Fail2Ban: restricted.go:51: Bantime: 3s
INFO: Fail2Ban: restricted.go:51: Findtime: 3h0m0s
INFO: Fail2Ban: restricted.go:51: FailToBan Rules : '{Xbantime:3s Xfindtime:3h0m0s Xurlregexp:[localhost:5000/whoami] Xmaxretry:4 Xenabled:true}'
INFO: Fail2Ban: restricted.go:52: Plugin: FailToBan is up and running
DEBUG: Fail2Ban: restricted.go:51: New request: &{GET /whoami HTTP/1.1 1 1
DEBUG: Fail2Ban: restricted.go:51: welcome ::1
DEBUG: Fail2Ban: restricted.go:51: New request: &{GET /whoami HTTP/1.1 1 1
DEBUG: Fail2Ban: restricted.go:51: welcome back ::1 for the 2 time
DEBUG: Fail2Ban: restricted.go:51: New request: &{GET /whoami HTTP/1.1 1 1
DEBUG: Fail2Ban: restricted.go:51: welcome back ::1 for the 3 time
DEBUG: Fail2Ban: restricted.go:51: New request: &{GET /whoami HTTP/1.1 1 1
DEBUG: Fail2Ban: restricted.go:52: ::1 is now banned temporarily
DEBUG: Fail2Ban: restricted.go:51: New request: &{GET /whoami HTTP/1.1 1 1
DEBUG: Fail2Ban: restricted.go:51: ::1 is still banned since 2021-04-23T21:40:55+02:00, 5 request
DEBUG: Fail2Ban: restricted.go:51: New request: &{GET /whoami HTTP/1.1 1 1
DEBUG: Fail2Ban: restricted.go:52: ::1 is no longer banned

Fail2ban

We plan to use all default fail2ban configuration but at this time only a few features are implemented:

testData:
  logLevel: "INFO"
  rules:
    urlregexps:
    - regexp: "/no"
      mode: block
    - regexp: "/yes"
      mode: allow
    bantime: "3h"
    findtime: "10m"
    maxretry: 4
    enabled: true

Where:

findtime: is the time slot used to count requests (if there is too many requests with the same ip in this slot of time, the ip goes into ban). You can use 'smart' strings: "4h", "2m", "1s", ...
bantime: correspond to the amount of time the IP is in Ban mode.
maxretry: number of request before Ban mode.
enabled: allow to enable or disable the plugin (must be set to true to enable the plugin).
urlregexp: a regexp list to block / allow requests with regexps on the url
logLevel: is used to show the correct level of logs (DEBUG, INFO, NONE)

URL Regexp

Urlregexp are used to defined witch part of your website will be either allowed, blocked or filtered :

allow : all requests where the url match the regexp will be forwarded to the backend without any check
block : all requests where the url match the regexp will be stopped

No definitions

testData:
  rules:
    bantime: "3h"
    findtime: "10m"
    maxretry: 4
    enabled: true

By default, fail2ban will be applied.

Multiple definition

testData:
  rules:
    urlregexps:
    - regexp: "/whoami"
      mode: allow
    - regexp: "/do-not-access"
      mode: block
    bantime: "3h"
    findtime: "10m"
    maxretry: 4
    enabled: true

In the case where you define multiple regexp on the same url, the order of process will be :

Block
Allow

In this example, all requests to /do-not-access will be denied and all requests to /whoami will be allowed without any fail2ban interaction.

Schema

First request, IP is added to the Pool, and the findtime timer is started:

A |------------->
  ↑

Second request, findtime is not yet finished thus the request is fine:

A |--x---------->
     ↑

Third request, maxretry is now full, this request is fine but the next wont.

A |--x--x------->
        ↑

Fourth request, too bad, now it's jail time, next request will go through after bantime:

A |--x--x--x---->
           ↓
B          |------------->

Fifth request, the IP is in Ban mode, nothing happen:

A |--x--x--x---->
B          |--x---------->
              ↑

Last request, the bantime is now over, another findtime is started:

A |--x--x--x---->            |------------->
                             ↑
B          |--x---------->

Dev `traefik.yml` configuration file for traefik

pilot:
  token: [REDACTED]

experimental:
  devPlugin:
    goPath: /home/${USER}/go
    moduleName: github.com/tomMoulard/fail2ban

entryPoints:
  http:
    address: ":8000"
    forwardedHeaders:
      insecure: true

api:
  dashboard: true
  insecure: true

providers:
  file:
    filename: rules-fail2ban.yaml

How to dev

$ docker run -d --network host containous/whoami -port 5000
# traefik --configfile traefik.yml

Authors

Tom Moulard	Clément David	Martin Huvelle	Alexandre Bossut-Lasry

madebymode/traefik-fail2ban