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Is this a secure messaging app?

https://github.com/positive-intentions/chat

probably not... Because I'm comparing it to everything... but id like to share some details about how my app works so you can tell me what im missing. id like to have wording in my app to say something like "most secure chat app in the world"... i probably cant do that because it doesnt qualify... but i want to understand why?

im not an expert on cyber security. im sure there are many gaps in my knowlege in this domain.

using javascript, i created a chat app. it is using peerjs-server to create an encrypted webrtc connection. this is then used to exchange additional encryption keys from cryptography functions built into browsers to add a redundent layer of encryption. the key exchange is done like diffie-helman over webrtc (which can be considered secure when exchanged over public channels)

  • i sometimes recieve feedback like "javascript is inherently insecure". i disagree with this and have opened sourced my cryptography module. its basically a thin wrapper around vanilla crypto functions of a browser. a prev post on the matter.

  • another concern for my kind of app (PWA) is that the developer may introduce malicious code. this is an important point for which i open sourced the project and give instructions for selfhosting. selhosting this app has some unique features. unlike many other selfhosted projects, this app can be hosted on github-pages for free (instructions are provided in the readme). im also working on introducing a way that users can selfhost federated modules. a prev post on the matter.

  • to prevent things like browser extensions, the app uses strict CSP headers to prevent unauthorised code from running. selfhosting users should take note of this when setting up their own instance.

  • i received feedback the Signal/Simplex protocol is great, etc. id like to compare that opinion to the observation in how my todo app demo works. (the work is all experimental work-in-progress and far from finished). the demo shows a simple functionality for a basic decentralized todo list. this should already be reasonably secure. i could add a few extra endpoints for exchanging keys diffie-helman style. which at this point is relatively trivial to implement. I think it's simplicity could be a security feature.

  • the key detail that makes this approach unique, is because as a webapp, unlike other solutions, users have a choice of using any device/os/browser.

i think if i stick to the principle of avoiding using any kind of "required" service provider (myself included) and allowing the frontend and the peerjs-server to be hosted independently, im on track for creating a chat system with the "fewest moving parts". im hope you will agree this is true p2p and i hope i can use this as a step towards true privacy and security. security might be further improved by using a trusted VPN.

i created a threat-model for the app in hopes that i could get a pro-bono security assessment, but understandable the project is too complicated for pro-bono work.

while there are several similar apps out there like mine. i think mine is distinctly a different approach. so its hard to find best practices for the functionalities i want to achieve. in particular security practices to use when using p2p technology.

(note: this app is an unstable, experiment, proof of concept and not ready to replace any other app or service. It's far from finished and provided for testing and demo purposes only. This post is to get feedback on the app to determine if i'm going in the right direction for a secure chat app)

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  • For it to be the most secure app in the world, you'd need to understand the main attack vectors, and how to mitigate them. You'd have to understand them and how you mitigate them better than how Signal or Element mitigate them. Finally, you'd have to get it audited by a reputable security auditor than will validate your claims.

    If you do not have the money, best bet is to have a donation method or 2, like Liberapay, Open Collective etc. and fund raise for it. Active users are more likely to donate, so get folk using it. Focus more on what it is and it's advantages. "A secure chat app that can be run regardless of hardware out of your browser*. Long term aims to be the most secure app in the world. Join us on that adventure."

    If you do not know, learn. If you really want to create the most secure chat app in the world, you have to become a subject matter expert, know the challenges and rivals. There is no shortcut in this. Depends how much you want this.

    Oh, and yeah, JS, if you're using node, keep your app and dependencies scanned and up to date constantly.

    • thanks for the advice and insights.

      in the post is my learnings of possible attack vectors and how to mitigate them. i try to go into more into exhaustive details in the threat model. do you think something is missing?

      unfortunaly i think i may be illiterate in funding and business side of things. i have tried to set up serveral donation platforms as seen on the repo. nobody has ever donated. this isnt a shock, considering its experiemental and unstable. i also dont know how to really ask for donations. is it something like saying "support us on Liberapay" at the end of a post? at best i can only hope to get a spike in donation and not enough for a security audit. ive asked around and it seems a decent assesment would cost a decent amount.

      i also tried applying for several grants. this was an exhausing experience and so i stopped. it seems the advice is too keep applying until bingo, but from the onset it isnt something i know anything about so no doubt several more rejections. (one particular rejection mentioned it wasnt as innovative as simplex). the whole process here is not understood, enjoyable or fruitful. i think its sometimes hard to explain concepts about the app on reddit and lemmy... im sure those concepts are further difficult to communicate and understand in an appealing grant application.

      i think the jorney to get the app to where it is has been a learning experience. not just about the apps technical details, but how to communicate about it publicly. ive regularly seeked advice on the approach. i dont have any qualifications in the field, which is an important challenge many point to. when can it be said that im a subject matter expert? i can create this app and i can answer questions about it, but im not ready for any cryptography exam.

      thanks again for you input.

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