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

probably not… 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 a cyber security expert. im sure there are many gaps in my knowlege of 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 (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 and instructions are provided. 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 think if 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 hoping this will lead to true p2p and i hope i can use this as a step towards true privacy and security.

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.

i created a decentralized todo list demo using the p2p framework used in the chat app. this is to demonstrate the bare-minimum functionality of decentralised messaging and state management.

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.

  • sugar_in_your_tea@sh.itjust.worksEnglish
    3·
    4 months ago

    Probably not, it’s probably “secure enough” though. I haven’t read through the code, just glanced at some of your top-level docs. I’ll browse through it later. :)

    If you want something really secure, check out Simplex Chat, it’s P2P and built on really solid tech. You essentially have a separate keypair exchange for every “channel,” which would be a 1:1 or group chat, and knowing the key, username, ID, etc to one channel doesn’t help you at all with another channel because there’s no shared, constant information at all. So if I’m chatting with users A, B, and C, and an attacker compromises A and B, there’s nothing to link me to both A and B, nor a way for them to know about C. The only way for an attacker to know about C is if they compromised my device, but then they wouldn’t know anything about C other than what they sent to me.

    You could probably build something on top of simplex and go to town with your own UX and whatnot on top, or study the Haskell code and figure out how they’re doing it. I’m working on a P2P lemmy/reddit clone, and I’m planning on using simplex for DMs and live chat, and perhaps as part of my trust network (I want distributed moderation as well).

    I’m not a cyber security expert either, just a hobbyist, and it’s the best I’ve found so far.

    • positive_intentions@lemmy.mlOPEnglish
      2·
      3 months ago

      thanks for the reply! im actively looking for a way to compare it to simplex chat. i hope you can offer some advice.

      here is a prev post about it. i think signal is a good app and works similarly to mine in many ways. but mine is distinct in that its provided as a PWA. the goal is specifically to create a secure chat app on a browser. simple provides all other offerings and perhaps came across feedback like i did that javascript is inherently insecure (to which, this app is my disagreement).

      my app works similarly to how to derscribe simplex to work. in my app what you see as a “pod” is basically a chat room. the app doesnt have the group-chat functionality working as expected, but its a work in progress. the following is an attempt to explain how it works. it will work in a way that a room has an id to which users can send messages p2p. this is how it works for regular chat. it works with a slight different that the messages are stored on a blockchain structure. it isnt related to cryptocurrencies or anything. just blockchain as a dastructure. this becomes useful for group chat because it could allow for offlike messaging by something like user A, B and C have a group chat. C goes offline while A and B continue to chat. then A goes offline and C comes online to talk to B. when C connects to B for the second time, the messages from A will be shared and resolved via the blockchain functionality. i make an attempt to explain the benefit of the blockchain structure here. it isnt something i can advocate as an approach. its more something i was trying out and it seems to work better than i thought.

      id like to hear more about your approach to distributed moderation. i was trying to investigate something like this and couldnt settle on an approach that would be useful. it would be great to hear your ideas if you want to share.