It astounds me that there's no non-invasive local solution to go to my router or whatever other appliances web page without my browser throwing warnings and calling it evil. Truly a fuck up(purposeful or not) by all involved in creating the standards. We need local TLS without the hoops.
Simplest possible, least invasive, most secure thing I can think of: QR code on the router with the CA cert of the router. Open cert manager app on laptop/phone, scan QR code, import CA cert. Comms are now secure (assuming nobody replaced the sticker).
The crazy thing? There is already two WiFi QR code standards, but they do not include the CA cert. There's a "Wi-Fi Easy Connect" standard that is intended to secure the network for an enterprise, and there's a random Java QR code library that made their own standard for just encoding an access point and WPA shared key (and Android and iOS both adopted it, so now it's a de-facto standard).
End-user security wasn't a consideration for either of them. With the former they only cared about protecting the enterprise network, and with the latter they just wanted to make it easier to get onto a non-Enterprise network. The user still has to fend for themselves once they're on the network.
This is a terrible solution. Now you require an Internet connection and a (non-abandoned) third party service to configure a LAN device. Not to mention countless industrial devices where operators would typically have no chance to see QR code.
The solution I just mentioned specifically avoids an internet connection or third parties. It's a self-signed cert you add to your computer's CA registry. 100% offline and independent of anything but your own computer and the router. The QR code doesn't require an internet connection. And the first standard I mentioned was designed for industrial devices.
Not only would that set a questionable precedent if users learn to casually add new trust roots, it would also need support for new certificate extensions to limit validity to that device only. It's far from obvious that would be a net gain for Internet security in general.
It might be easier to extend the URL format with support for certificate fingerprints. It would only require support in web browsers, which are updated much faster than operating systems. It could also be made in a backwards compatible way, for example by extending the username syntax. That way old browsers would continue to show the warning and new browsers would accept the self signed URL format in a secure way.
Have you seen the state of typical consumer router firmwares? Security hasn’t been a serious concern for a decade plus.
They only stopped using global default passwords because people were being visibly compromised on the scale of millions at a time.
Good point. There are exceptions though. Eero, for example.
Your router should use acme with a your-slug.network.home (a communal one would be nice, but more realistically some vendor specific domain suffix that you could cname) domain name and then you should access it via that, locally. your router should run ideally splitbrain dns for your network. if you want you can check a box and make everything available globally via dns-sd.
Wouldn't that allow the router to MITM all encrypted data that goes through it?
If it were a CA cert yes. It could instead be a self-signed server (non-CA) cert, that couldn't be used for requests to anything else.
All my personal and professional feelings aside (they are mixed) it would be fascinating to consider a subnet based TLS scheme. Usually I have to bang on doors to manage certs at the load balancer level anyway.
I’ve actually put a decent amount of thought into this. I envision a raspberry pi sized device, with a simple front panel ui. This serves as your home CA. It bootstraps itself witha generated key and root cert and presents on the network using a self-issued cert signed by the bootstrapped CA. It also shows the root key fingerprint on the front panel. On your computer, you go to its web UI and accept the risk, but you also verify the fingerprint of the cert issuer against what’s displayed on the front panel. Once you do that, you can download and install your newly trusted root. Do this on all your machines that want to trust the CA. There’s your root of trust.
Now for issuing certs to devices like your router, there’s a registration process where the device generates a key and requests a cert from the CA, presenting its public key. It requests a cert with a local name like “router.local”. No cert is issued but the CA displays a message on its front panel asking if you want to associate router.local with the displayed pubkey fingerprint. Once you confirm, the device can obtain and auto renew the cert indefinitely using that same public key.
Now on your computer, you can hit local https endpoints by name and get TLS with no warnings. In an ideal world you’d get devices to adopt a little friendly UX for choosing their network name and showing the pubkey to the user, as well as discovering the CA (maybe integrate with dhcp), but to start off you’d definitely have to do some weird hacks.
This is incredibly convoluted scenario for a use case with near zero chance of a MITM attack. Security ops is cancer.
Please tell me this is satire.
What can I say, I am a pki nerd and I think the state of local networking is significantly harmed by consumer devices needing to speak http (due to modern browsers making it very difficult to use). This is less about increasing security and more about increasing usability without also destroying security by coaching people to bypass cert checks. And as home networks inevitably become more and more crowded with devices, I think it will be beneficial to be able to strongly identify those devices from the network side without resorting to keeping some kind of inventory database, which nobody is going to do.
It also helps that I know exactly how easy it is to build this type of infrastructure because I have built it professionally twice.
Why should your browser trust the router's self-signed certificate? After you verify that it is the correct cert you can configure Firefox or your OS to trust it.
Because local routers by definition control the (proposed?) .internal TLD, while nobody controls the .local mDNS/Zeroconf one, so the router or any local network device should arguably be trusted at the TLS level automatically.
Training users to click the scary “trust this self-signed certificate once/always” button won’t end well.
Honestly, I'd just like web browsers to not complain when you're connecting to an IP on the same subnet by entering https://10.0.0.1/ or similar.
Yes, it's possible that the system is compromised and it's redirecting all traffic to a local proxy and that it's also malicious.
It's still absurd to think that the web browser needs to make the user jump through the same hoops because of that exceptional case, while having the same user experience as if you just connected to https://bankofamerica.com/ and the TLS cert isn't trusted. The program should be smarter than that, even if it's a "local network only" mode.
Certificates protect against man in the middle attacks and those are a thing on local networks.
I wonder what this would look like: for things like routers, you could display a private root in something like a QR code in the documentation and then have some kind of protocol for only trusting that root when connecting to the router and have the router continuously rotate the keys it presents.
Yeah, what they'll do is put a QR code on the bottom, and it'll direct you to the app store where they want you to pay them $5 so they can permanently connect to your router and gather data from it. Oh, and they'll let you set up your WiFi password, I guess.
That's their "solution".