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Show HN: Open-source private home security camera system (end-to-end encryption)

(github.com)
551 points arrdalan | 2 comments | 30 Nov 24 22:13 UTC | HN request time: 0.9s | source

I needed a security camera inside my house, one that would send motion notifications to my smartphone and would allow me to livestream remotely. However, I could not find one that I could trust due to privacy concerns. Many of them upload the plaintext of videos to their servers and none is fully open-source as far as I know. Therefore, I decided to use my spare time to build one from scratch. Called Privastead (as in Private Homestead), it uses OpenMLS for end-to-end encryption (between the camera local hub and the smartphone) and is mostly implemented in Rust (except for part of the Android app that is implemented in Kotlin). The system is functional now and I've been using it in my own house for the past couple of weeks.

Based on some of the discussions I've seen online, it seems like there are other users who are also concerned with the privacy implications of home security cameras. Therefore, I decided to open source my solution for everyone to use. If you need a privacy-preserving home security camera, please give it a try and provide feedback. Note that trying out the system requires you to have a supported IP camera, a local machine connected to the IP camera, a server, and an Android smartphone. I have put together detailed instructions on setting up the system, which I hope makes it easier for others to get the system up and running.

In addition, consider contributing to the project. The prototype currently has a lot of limitations: mainly that it has only been tested with one IP camera, only allows the use of one camera, and only supports Android. I'll continue to improve the prototype as time permits, but progress will be much faster if there are other contributors as well.

1. coppsilgold ◴[01 Dec 24 22:41 UTC] No.42291276[source]▶
Using a KEM[1] to create a sealed_box[2] type construct would allow for privacy even in a situation where the camera hardware is physically seized. You could also use ML-KEM (aka Kyber), McEliece-KEM and ECDH or RSA-KEM together to provide post quantum resistance.

The traditional symmetric approach (which also has post quantum resistance) in such systems requires the camera hardware to possess the long-lived symmetric key which can be extracted after seizure. Using a ratcheting mechanism (hashing the key every t time) can help - but have no self healing and be vulnerable to recovery from persistent storage (past keys may not be securely erased).

[1] <https://en.wikipedia.org/wiki/Key_encapsulation_mechanism>

[2] <https://libsodium.gitbook.io/doc/public-key_cryptography/sea...>

replies(1): >>42293079 #
2. arrdalan ◴[02 Dec 24 04:21 UTC] No.42293079[source]▶
Privastead/OpenMLS erases past keys from persistent storage in order not to suffer from the vulnerability you mentioned.