mirror of
https://github.com/docker-mailserver/docker-mailserver.git
synced 2024-01-19 02:48:50 +00:00
120 lines
4.3 KiB
Markdown
120 lines
4.3 KiB
Markdown
---
|
|
title: 'Security | Fail2Ban'
|
|
hide:
|
|
- toc # Hide Table of Contents for this page
|
|
---
|
|
|
|
Fail2Ban is installed automatically and bans IP addresses for 3 hours after 3 failed attempts in 10 minutes by default.
|
|
|
|
## Configuration files
|
|
|
|
If you want to change this, you can easily edit our github example file: [`config-examples/fail2ban-jail.cf`][github-file-f2bjail].
|
|
|
|
You can do the same with the values from `fail2ban.conf`, e.g `dbpurgeage`. In that case you need to edit: [`config-examples/fail2ban-fail2ban.cf`][github-file-f2bconfig].
|
|
|
|
The configuration files need to be located at the root of the `/tmp/docker-mailserver/` volume bind (usually `./docker-data/dms/config/:/tmp/docker-mailserver/`).
|
|
|
|
This following configuration files from `/tmp/docker-mailserver/` will be copied during container startup.
|
|
|
|
- `fail2ban-jail.cf` -> `/etc/fail2ban/jail.d/user-jail.local`
|
|
- `fail2ban-fail2ban.cf` -> `/etc/fail2ban/fail2ban.local`
|
|
|
|
### Docker-compose config
|
|
|
|
Example configuration volume bind:
|
|
|
|
```yaml
|
|
volumes:
|
|
- ./docker-data/dms/config/:/tmp/docker-mailserver/
|
|
```
|
|
|
|
!!! attention
|
|
`docker-mailserver` must be launched with the `NET_ADMIN` capability in order to be able to install the nftables rules that actually ban IP addresses.
|
|
|
|
Thus either include `--cap-add=NET_ADMIN` in the `docker run` command, or the equivalent in `docker-compose.yml`:
|
|
|
|
```yaml
|
|
cap_add:
|
|
- NET_ADMIN
|
|
```
|
|
|
|
## Running fail2ban in a rootless container
|
|
|
|
[`RootlessKit`][rootless::rootless-kit] is the _fakeroot_ implementation for supporting _rootless mode_ in Docker and Podman. By default RootlessKit uses the [`builtin` port forwarding driver][rootless::port-drivers], which does not propagate source IP addresses.
|
|
|
|
It is necessary for `fail2ban` to have access to the real source IP addresses in order to correctly identify clients. This is achieved by changing the port forwarding driver to [`slirp4netns`][rootless::slirp4netns], which is slower than `builtin` but does preserve the real source IPs.
|
|
|
|
### Docker with `slirp4netns` port driver
|
|
|
|
For [rootless mode][rootless::docker] in Docker, create `~/.config/systemd/user/docker.service.d/override.conf` with the following content:
|
|
|
|
```
|
|
[Service]
|
|
Environment="DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER=slirp4netns"
|
|
```
|
|
|
|
And then restart the daemon:
|
|
|
|
```console
|
|
$ systemctl --user daemon-reload
|
|
$ systemctl --user restart docker
|
|
```
|
|
|
|
!!! note
|
|
|
|
This changes the port driver for all rootless containers managed by Docker.
|
|
|
|
Per container configuration is not supported, if you need that consider Podman instead.
|
|
|
|
### Podman with `slirp4netns` port driver
|
|
|
|
[Rootless Podman][rootless::podman] requires adding the value `slirp4netns:port_handler=slirp4netns` to the `--network` CLI option, or `network_mode` setting in your `docker-compose.yml`.
|
|
|
|
|
|
You must also add the ENV `NETWORK_INTERFACE=tap0`, because Podman uses a [hard-coded interface name][rootless::podman::interface] for `slirp4netns`.
|
|
|
|
|
|
!!! example
|
|
|
|
```yaml
|
|
services:
|
|
mailserver:
|
|
network_mode: "slirp4netns:port_handler=slirp4netns"
|
|
environment:
|
|
- ENABLE_FAIL2BAN=1
|
|
- NETWORK_INTERFACE=tap0
|
|
...
|
|
```
|
|
|
|
!!! note
|
|
|
|
`slirp4netns` is not compatible with user-defined networks.
|
|
|
|
## Manage bans
|
|
|
|
You can also manage and list the banned IPs with the [`setup.sh`][docs-setupsh] script.
|
|
|
|
### List bans
|
|
|
|
```sh
|
|
./setup.sh fail2ban
|
|
```
|
|
|
|
### Un-ban
|
|
|
|
Here `192.168.1.15` is our banned IP.
|
|
|
|
```sh
|
|
./setup.sh fail2ban unban 192.168.1.15
|
|
```
|
|
|
|
[docs-setupsh]: ../setup.sh.md
|
|
[github-file-f2bjail]: https://github.com/docker-mailserver/docker-mailserver/blob/master/config-examples/fail2ban-jail.cf
|
|
[github-file-f2bconfig]: https://github.com/docker-mailserver/docker-mailserver/blob/master/config-examples/fail2ban-fail2ban.cf
|
|
[rootless::rootless-kit]: https://github.com/rootless-containers/rootlesskit
|
|
[rootless::port-drivers]: https://github.com/rootless-containers/rootlesskit/blob/v0.14.5/docs/port.md#port-drivers
|
|
[rootless::slirp4netns]: https://github.com/rootless-containers/slirp4netns
|
|
[rootless::docker]: https://docs.docker.com/engine/security/rootless
|
|
[rootless::podman]: https://github.com/containers/podman/blob/v3.4.1/docs/source/markdown/podman-run.1.md#--networkmode---net
|
|
[rootless::podman::interface]: https://github.com/containers/podman/blob/v3.4.1/libpod/networking_slirp4netns.go#L264
|