I currently have a home server which I use a lot and has a few important things in it, so I kindly ask help making this setup safer.
I have an openWRT router on my home network with firewall active. The only open ports are 443 (for all my services) and 853 (for DoT).
I am behind NAT, but I have ipv6, so I use a domain to point to my ipv6, which is how I access my serves when I am not on lan and share stuff with friends.
On port 443 I have nginx acting as a reverse proxy to all my services, and on port 853 I have adguardhome. I use a letsencrypt certificate with this proxy.
Both nginx, adguardhome and almost all of my services are running in containers. I use rootless podman for containers. My network driver is pasta, and no container has "--net host", although the containers can access host services because they have the option "--map-guest-addr" set, so I don't know if this is any safer then "--net host".
I have two means of accessing the server via ssh, either password+2fa or ssh key, but ssh port is lan only so I believe this is fine.
My main concern is, I have a lot of personal data on this server, some things that I access only locally, such as family photos and docs (these are literally not acessible over wan and I wouldnt want them to be), and some less critical things which are indeed acessible externally, such as my calendars and tasks (using caldav and baikal), for exemple.
I run daily encrypted backups into OneDrive using restic+backrest, so if the server where to die I believe this would be fine. But I wouldnt want anyone to actually get access to that data. Although I believe more likely than not an invader would be more interested in running cryptominers or something like that.
I am not concerned about dos attacks, because I don't think I am a worthy target and even if it were to happen I can wait a few hours to turn the server back on.
I have heard a lot about wireguard - but I don't really understand how it adds security. I would basically change the ports I open. Or am I missing something?
So I was hoping we could talk about ways to improve my servers security.
Wireguard is a VPN, so that's not going to help you much here unless you're forwarding all your traffic through a remote server, in which case anyone gets in there will still be able to get your local machines. It's another hop in the chain, but that's about it.
If you want to be more on guard about reacting to attacks, or just bad traffic, you probably want something like Crowdsec. You'll at least be able to detect and ban IPs probing your services. If that's too much work, leverage OoenWRT reporting and some scripting to ban bad actors that probe your firewall and open ports. That's a good first step.
If you're concerned about the containers, consider using something more secure than dockerd. Podman rootless with a dedicated service user is a good start. Then maybe look at something more complex: Kata, gvisor, lxc...etc. The goal being sandboxing the containers more to prevent jailbreaks.
Thanks for the amazing reply and specially for the explanation regarding wireguard.
I didnt know about crowsec and kata containers, both amazing projects, I will definetely look into it and try to set them up.
Just one quick follow up question, when you mention dedicanted service user, do you mean its best to have a sepate user for each service, such as one for nginx, one for adguardhome and so on? Currently all of them run under the same user and I didnt think about this possibility before.
Yeah, so if you're running rootless containers, they aren't run by root, and for added security, you don't want them run by your normal user because if they get broken, then they'd have access to what your user has access to. Just create another user that only runs containers, and doesn't have access to your things or root.
That makes a lot of sense. Thats also very easy to setup so I will do it tonight.
Thanks again for your amazing input!