gitea/docs/content/doc/administration/fail2ban-setup.en-us.md
John Olheiser bb25f85ce8
Refactor docs (#23752)
This was intended to be a small followup for
https://github.com/go-gitea/gitea/pull/23712, but...here we are.

1. Our docs currently use `slug` as the entire URL, which makes
refactoring tricky (see https://github.com/go-gitea/gitea/pull/23712).
Instead, this PR attempts to make future refactoring easier by using
slugs as an extension of the section. (Hugo terminology)
- What the above boils down to is this PR attempts to use directory
organization as URL management. e.g. `usage/comparison.en-us.md` ->
`en-us/usage/comparison/`, `usage/packages/overview.en-us.md` ->
`en-us/usage/packages/overview/`
- Technically we could even remove `slug`, as Hugo defaults to using
filename, however at least with this PR it means `slug` only needs to be
the name for the **current file** rather than an entire URL
2. This PR adds appropriate aliases (redirects) for pages, so anything
on the internet that links to our docs should hopefully not break.
3. A minor nit I've had for a while, renaming `seek-help` to `support`.
It's a minor thing, but `seek-help` has a strange connotation to it.
4. The commits are split such that you can review the first which is the
"actual" change, and the second is added redirects so that the first
doesn't break links elsewhere.

---------

Signed-off-by: jolheiser <john.olheiser@gmail.com>
2023-04-28 11:33:41 +08:00

4.2 KiB

date title slug weight toc draft aliases menu
2018-05-11T11:00:00+02:00 Fail2ban Setup fail2ban-setup 16 false false
/en-us/fail2ban-setup
sidebar
parent name weight identifier
administration Fail2ban setup 16 fail2ban-setup

Fail2ban setup to block users after failed login attempts

Remember that fail2ban is powerful and can cause lots of issues if you do it incorrectly, so make sure to test this before relying on it so you don't lock yourself out.

Gitea returns an HTTP 200 for bad logins in the web logs, but if you have logging options on in app.ini, then you should be able to go off of log/gitea.log, which gives you something like this on a bad authentication from the web or CLI using SSH or HTTP respectively:

2018/04/26 18:15:54 [I] Failed authentication attempt for user from xxx.xxx.xxx.xxx
2020/10/15 16:05:09 modules/ssh/ssh.go:143:publicKeyHandler() [W] Failed authentication attempt from xxx.xxx.xxx.xxx

(DEPRECATED: This may be a false positive as the user may still go on to correctly authenticate.)

2020/10/15 16:05:09 modules/ssh/ssh.go:155:publicKeyHandler() [W] Failed authentication attempt from xxx.xxx.xxx.xxx

(DEPRECATED: This may be a false positive as the user may still go on to correctly authenticate.)

2020/10/15 16:05:09 modules/ssh/ssh.go:198:publicKeyHandler() [W] Failed authentication attempt from xxx.xxx.xxx.xxx

(DEPRECATED: This may be a false positive as the user may still go on to correctly authenticate.)

2020/10/15 16:05:09 modules/ssh/ssh.go:213:publicKeyHandler() [W] Failed authentication attempt from xxx.xxx.xxx.xxx

(DEPRECATED: This may be a false positive as the user may still go on to correctly authenticate.)

2020/10/15 16:05:09 modules/ssh/ssh.go:227:publicKeyHandler() [W] Failed authentication attempt from xxx.xxx.xxx.xxx

(DEPRECATED: This may be a false positive as the user may still go on to correctly authenticate.)

2020/10/15 16:05:09 modules/ssh/ssh.go:249:sshConnectionFailed() [W] Failed authentication attempt from xxx.xxx.xxx.xxx

(From 1.15 this new message will available and doesn't have any of the false positive results that above messages from publicKeyHandler do. This will only be logged if the user has completely failed authentication.)

2020/10/15 16:08:44 ...s/context/context.go:204:HandleText() [E] invalid credentials from xxx.xxx.xxx.xxx

Add our filter in /etc/fail2ban/filter.d/gitea.conf:

# gitea.conf
[Definition]
failregex =  .*(Failed authentication attempt|invalid credentials|Attempted access of unknown user).* from <HOST>
ignoreregex =

Add our jail in /etc/fail2ban/jail.d/gitea.conf:

[gitea]
enabled = true
filter = gitea
logpath = /var/lib/gitea/log/gitea.log
maxretry = 10
findtime = 3600
bantime = 900
action = iptables-allports

If you're using Docker, you'll also need to add an additional jail to handle the FORWARD chain in iptables. Configure it in /etc/fail2ban/jail.d/gitea-docker.conf:

[gitea-docker]
enabled = true
filter = gitea
logpath = /var/lib/gitea/log/gitea.log
maxretry = 10
findtime = 3600
bantime = 900
action = iptables-allports[chain="FORWARD"]

Then simply run service fail2ban restart to apply your changes. You can check to see if fail2ban has accepted your configuration using service fail2ban status.

Make sure and read up on fail2ban and configure it to your needs, this bans someone for 15 minutes (from all ports) when they fail authentication 10 times in an hour.

If you run Gitea behind a reverse proxy with Nginx (for example with Docker), you need to add this to your Nginx configuration so that IPs don't show up as 127.0.0.1:

proxy_set_header X-Real-IP $remote_addr;

The security options in app.ini need to be adjusted to allow the interpretation of the headers as well as the list of IP addresses and networks that describe trusted proxy servers (See the configuration cheat sheet for more information).

REVERSE_PROXY_LIMIT = 1
REVERSE_PROXY_TRUSTED_PROXIES = 127.0.0.1/8 ; 172.17.0.0/16 for the docker default network