Tag: OPNsense

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Learning OPNsense: DNS Adblocking

Good Morning from my Robotics Lab! This is Shadow_8472 with another short update my progress with my OPNsense firewall. Let’s get started.

I have done a substantial amount of work with DNS on my home network, but as noted in a previous post, it’s sub-optimal to exclusively manipulate your Domain Name System access from a power-hungry desktop when you sometimes have to ration electricity in your Uninterruptible Power Supply (UPS). I like PiHole’s web interface with all its fancy, moving graphs and charts, but our new firewall, Cerberus, can replicate the functionality I need.

I primarily use PiHole for DNS ad blocking, but I also explicitly blacklist a few URL’s while hosting local DNS records for servers on my Local Area Network (LAN), though the later is a work in progress.

OPNsense→Services→Unbound DNS→Blocklist→Type of DNSBL offers a drop-down checkbox menu of block lists. This is in contrast to PiHole→Adlists, which lets you import lists from arbitrary sources (edit the day after posting: OPNsense Unbound does have a URLs of Blocklists field). Either way, it should go without saying that sites and ads only need to be blocked once; it will only slow your DNS service down if given a bunch of redundant lists. From what I remember installing OISD Big onto PiHole, they aggregate several of these lists and remove the duplicates. PiHole also picked up a list named StephenBlack with a comment, “Migrated from /etc/pihole/adlists.list.” It sounds like a system default, but in any case, I found it had stuff not on OISD Big. OPNsense Unbound has the option for it, so it got migrated.

Migrating singled-out blacklist items was as simple as adding each entry to a comma-separated list (where PiHole wants separate entries). I’m going to wait on migrating my LAN domain names though. I believe I found the place to do it, but ButtonMash isn’t running Caddy to recognize subdomain requests right now.

One last step was to get into the red gaming router we’ve been using and point its DNS at Cerberus the Firewall. I then pointed its secondary DNS alternative at ButonMash.

To summarize, we should have the exact same protection as before on a smaller battery footprint and within the firewall’s default attack surface to boot!

Encrypted DNS

One of my eventual goals is to have my own recursive DNS server, which seeks out an a URL’s authoritative DNS record if it doesn’t have it cached. This will increase privacy, but I haven’t figured it out at a production grade yet. Instead, I looked up the best free and privacy respecting DNS, and so far as I can tell, that’s Cloudflare at 1.1.1.1.

From OPNsense, it wasn’t much more trouble to encrypt using DNS over TLS. I would prefer DNS over HTTPS, does the same thing but camouflages DNS requests as normal web traffic. For now, I’m assuming Unbound can’t do this and working properly. Please tell me if I’m wrong.

Takeaway

It’s slow going, but I am moving into Cerberus. While looking around, I found a module for NUT (Network UPS Tools), a utility for shutting down computers gracefully as their UPS runs down. I wanted to get it working, and for a moment after a reboot I did, but for reasons beyond me besides the driver on BSD not agreeing the best with CyberPower UPS systems, I’m at a loss. At this point, I am thinking to install a small Linux box to do the job at a future date, even though that will be yet another thing on the UPS.

Final Question

From above: Do you know of a way for OPNsense’s Unbound module to run DNS over HTTPS? I look forward to hearing from you in the comments below or on my Socials!

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Unboxing: Hardware Firewall (Protectli Vault)

Good Morning from my Robotics Lab! This is Shadow_8472 and today I have on my desk between my keyboard and monitors a new Protectli Vault running OPNsense. Let’s get started.

After at least a couple years tentatively researching hardware firewalls, it’s here. Let me tell you: it’s both a relief and a bit of pressure. I’m glad I’m no longer starting from scratch over and over again, but now I feel time pressure to deploy it despite my parents’ assurance that it’s much better to go at a responsible pace. And unless you’re a full time network specialist, that pace is longer than a week.

My Current Network and Its Weaknesses

At present, my home network starts with a box owned and controlled by my service provider. This gateway feeds into a gaming router before going out to a couple switches and Wi-Fi. One of my desktops has OpenWRT on a Raspberry Pi 4. ButtonMash, my home server, runs Podman containers for Vaultwarden (Password vault storage) and PiHole (DNS ad blocking). We have a Network Attached Storage by the hostname of GoldenOakLibry. Everything minus a couple workstations has battery backup in case the lights go out.

And when the lights do go out, the first big flaw comes out. While the network closet may last several hours, Power-hungry ButtonMash and GoldenOakLibry chew through their shared battery in around half an hour before I added ButtonMash’s twin, Joystick, as a development platform. When ButtonMash goes down, the network loses DNS so we can’t resolve URL’s.

Additionally, I’d like to move to a non-default set of internal IP addresses, like 10.59.102.X instead of 10.0.0.X or 192.168.0.X. While computers getting automatic IP’s over DHCP will essentially take care of themselves, I have invested quite a bit of time into static IP’s on NFS (Network File System), and when I move GoldenOakLibry’s IP, I’ll need to adjust the automounts for all systems accessing it, and that’s just a pain. I want to learn how a home domain works.

I also have a number of network-related projects I’ve done research for, but burned out on before solving. From memory, here’s a checklist of partial/incomplete/need-to-redo projects:

  • Feline Observation Pi (First prototype tested, needs overhaul)
  • Website for family photo archive (Needs hardware firewall, rootless Podman/NFS, booru/wiki)
  • Nextcloud (Early prototype successful, needs rootless Podman/NFS before production)
  • Beowulf cluster (Early research)
  • Rootless Podman/NFS (Heard from a developer and solution may not exist [yet])
  • UPS battery monitoring/shutdown before power failure (Research phase)
  • Caddy (First prototype in production, needs overhaul)
  • Unbound (Incomplete prototype)
  • Reverse VPN [mobile traffic] (Need Hardware Firewall)
  • Podman systemctl –user (In production, but I cannot reproduce at will)
  • Domain/Domain Controller (Background research incomplete)

Keep in mind that the notes on each item suggesting a direction are just the direction I’m leaning in at the moment without reflecting the new hardware. Replacing GoldenOakLibry with a server beefy enough to handle running Podman would solve my current need for rootless Podman/NFS. I may find a replacement for Caddy that also works as a Domain Controller. Does Caddy even do that? Let me check… Inconclusive; probably not. I don’t know enough about what to look for in a Domain Controller besides the name. Most of my time focused on researching Demilitarized Zones.

Demilitarized Zone and Roadmapping

Originally, I had a goal of deploying this new firewall/router configured with a demilitarized zone network structure. With hardware in hand, I learned a lot! But as I learned, I realized I needed to learn that much more to do the job right. A DMZ is basically a low security area of your network for serving stuff over an untrusted network (usually the wide open Internet) while protecting your Local Area Network. Ideally your LAN would have a separate physical router in case the one servicing the DMZ is ever compromised, but a homelab environment should be a small enough target that branching off from a single hardened router should be fine. My trouble is that I can’t fully tell where to put what.

I already know I want to move PiHole, Unbound, and similar projects related to internet traffic, and other projects I want lasting a bit longer into power outages onto the new router. OPNsense is a distribution of BSD and not Linux, so I expect I will need to look into a Linux Virtual Machine if BSD-based containers aren’t available. The gaming router I’m using now will still be our Wi-Fi access point, but I’d prefer to retire it from DHCP duty.

ButtonMash and Joystick are my enigma. I had plans of clustering them, but I may need one in the DMZ and one on the LAN. GoldenOakLibry belongs on the LAN so far as I can tell – as do all workstations.

Takeaway

There will be more thought to give it another week. I went ahead and hooked it up in place, but it didn’t work despite how I had previously had it working between my upstairs workstation and its rPi router. I’ve reverted the setup to how it was before, and I’ll need to take a closer look and do some further testing.

Final Question

What was the last piece of tech you unboxed?

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