this post was submitted on 17 Feb 2024
67 points (97.2% liked)

Privacy

31975 readers
671 users here now

A place to discuss privacy and freedom in the digital world.

Privacy has become a very important issue in modern society, with companies and governments constantly abusing their power, more and more people are waking up to the importance of digital privacy.

In this community everyone is welcome to post links and discuss topics related to privacy.

Some Rules

Related communities

Chat rooms

much thanks to @gary_host_laptop for the logo design :)

founded 5 years ago
MODERATORS
 

Is there a community specific to FOSS or just general privacy oriented IoT? With plenty of hardware discussion along with software. Routers, piholes, Meshtastic, anything IoT but open source. If it touches a network but you want it to do something it doesn't. Flashing a doorbell camera with FOSS firmware. Hosting media servers on your phones Hotspot. Loading gcode to a printer from anywhere. There are so many things and possibilities.

If there isn't someone should start one, OpenIoT or something catchy and relevant.

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 7 points 9 months ago (1 children)

Your Https connections are also symmetric, so that's a silly thing to dislike.

The handshake and key exchange are asymmetric, and used to establish a symmetric session key.

ZigBee encryption is fine for the use case, because you're only adding devices you know are being added. You inherently trust that your physical ZigBee device is the device it claims to be.

There's potentially an opportunity to hijack the key exchange between devices at network join, but you'd have to approve the listening device to your network in the first place.

https://development.libelium.com/zigbee-networking-guide/security-and-data-encryption

[–] [email protected] 6 points 9 months ago (1 children)

Thank you for clarifying, and my apologies

[–] [email protected] 4 points 9 months ago (1 children)

No apology needed, one thing about security is that paranoia is good. One problem with security is that paranoia leads to assumptions and misinformation, rather than understanding.

Symmetric key encryption is much faster than asymmetric, and can use much larger keys with less compute penalty. So we use acPU intensive asymmetric TLS handshakes to safely exchange the keys, and then switch to the faster method for the data.

So when ZigBee use AES 128, you can be reasonably sure the data packets are safe. The next question to ask is "do they exchange their keys safely?"

Which in this case would be "no" if you just leave the ZigBee controller in pairing mode all the time. However, you only allow pairing when you want it, and only pair with devices you explicitly allow. Unauthorized devices never get your network key.

[–] [email protected] 1 points 9 months ago (1 children)

Could you tell me more about how secure the key exchange is?

[–] [email protected] 2 points 9 months ago (1 children)

Check the link I posted above, or you can look at the 802.15.4 wiki for an overview.

https://en.m.wikipedia.org/wiki/IEEE_802.15.4, scroll to the security section.

[–] [email protected] 2 points 9 months ago