4 ms·

hey, I literally doing this right now, what's wrong with that?? I mean its just for notification to my app so its not something critical

8-prime 1y ago
When the message you push out through that websocket are something that server knows about intrinsically, as in, the message contents are produced by the server there is nothing wrong with the approach. When your server facilitates a communication between two clients and just acts as the infrastructure E2EE can become relevant. If the clients want to be able to exchange information withouth the server being able to snoop in on what is being sent, then you'd want to use E2EE. With that the server won't be able to read what is being sent.
- tonyhart7 1y ago
  - I have public chat that user can chatting in public room (seems like I dont need for this one) - then notification service is probably something I want to E2EE then, but Idk about performance hit cost would be
  - 0xFEE1DEAD 1y ago
    A public chat - like one that anyone can join at any time without needing an invitation? If so, then you really don't need any extra encryption. If not, then it depends on who's using your chat, how they use it, and for what purpose. Are the users of the chat room a small group with occasional users joining or leaving, or are many users expected to join and leave at any given moment? That being said, encrypting the notifications won't bring any real benefits. A bad actor would simply focus on trying to compromise your server. If you do decide that full e2ee would benefit your users, then look for someone who can help you implement it. Implementing real e2ee for a 2 party chat is hard for someone without experience. Implementing e2ee for a group chat is hard even for someone with experience.
    - tonyhart7 1y ago
      welp, I am just gonna look at Telegram/Signal source and make a lite version for it
      - mort96 1y ago
        I don't think you want to look at the source code, and I don't think you want to look at Telegram. You should have a look at the Signal Protocol: https://en.m.wikipedia.org/wiki/Signal_Protocol https://en.m.wikipedia.org/wiki/Signal_Protocol. It's well documented. Maybe there are libraries which implement it. (Though I still think that "how can I protect against TLS being broken?" is the wrong question and you should instead ask "how can I ensure that TLS doesn't break?".)
mort96 1y ago
If your threat model is such that it's perfectly fine for the server to know everything that's coming from and going to the client, there's no problem at all. That's probably your situation, it's okay that the server knows what notifications it's sending to your app. If your threat model is such that you'd rather not have the server know what's sent to and from the client, it's not enough to just encrypt the data in flight, which is what HTTPS does. With encrypted chat, we typically want what we refer to as end-to-end encryption, where the server can't see the content of messages sent between users.
- tonyhart7 1y ago
  then what happen if E2EE receiver is server itself??? I want to prevent vector attack such MiTM if TLS is somehow hacked
  - mort96 1y ago
    In a typical server-backed web app architecture, TLS is the protection against MITM. You're gonna have a really really hard time making something which protects against MITM better than TLS. There are things you can do to make it more difficult to hack your TLS connection though, for example you could use key pinning to make sure that your app will only accept a server with the certificate you expect. This would protect against an IT admin installing root certs on their users' devices, or against certificate authorities issuing fake certificates for your domain.
    - tonyhart7 1y ago
      Yeah this app maybe don't need that but for things like IoT running websocket connection for long time maybe I need that
  - hiimkeks 1y ago
    Ah, the Zoom Gambit
    - tonyhart7 1y ago

8-prime 1y ago

When the message you push out through that websocket are something that server knows about intrinsically, as in, the message contents are produced by the server there is nothing wrong with the approach. When your server facilitates a communication between two clients and just acts as the infrastructure E2EE can become relevant. If the clients want to be able to exchange information withouth the server being able to snoop in on what is being sent, then you'd want to use E2EE. With that the server won't be able to read what is being sent.

tonyhart7 1y ago
- I have public chat that user can chatting in public room (seems like I dont need for this one) - then notification service is probably something I want to E2EE then, but Idk about performance hit cost would be
- 0xFEE1DEAD 1y ago
  A public chat - like one that anyone can join at any time without needing an invitation? If so, then you really don't need any extra encryption. If not, then it depends on who's using your chat, how they use it, and for what purpose. Are the users of the chat room a small group with occasional users joining or leaving, or are many users expected to join and leave at any given moment? That being said, encrypting the notifications won't bring any real benefits. A bad actor would simply focus on trying to compromise your server. If you do decide that full e2ee would benefit your users, then look for someone who can help you implement it. Implementing real e2ee for a 2 party chat is hard for someone without experience. Implementing e2ee for a group chat is hard even for someone with experience.
  - tonyhart7 1y ago
    welp, I am just gonna look at Telegram/Signal source and make a lite version for it
    - mort96 1y ago
      I don't think you want to look at the source code, and I don't think you want to look at Telegram. You should have a look at the Signal Protocol: https://en.m.wikipedia.org/wiki/Signal_Protocol https://en.m.wikipedia.org/wiki/Signal_Protocol. It's well documented. Maybe there are libraries which implement it. (Though I still think that "how can I protect against TLS being broken?" is the wrong question and you should instead ask "how can I ensure that TLS doesn't break?".)

mort96 1y ago

If your threat model is such that it's perfectly fine for the server to know everything that's coming from and going to the client, there's no problem at all. That's probably your situation, it's okay that the server knows what notifications it's sending to your app. If your threat model is such that you'd rather not have the server know what's sent to and from the client, it's not enough to just encrypt the data in flight, which is what HTTPS does. With encrypted chat, we typically want what we refer to as end-to-end encryption, where the server can't see the content of messages sent between users.

tonyhart7 1y ago
then what happen if E2EE receiver is server itself??? I want to prevent vector attack such MiTM if TLS is somehow hacked
- mort96 1y ago
  In a typical server-backed web app architecture, TLS is the protection against MITM. You're gonna have a really really hard time making something which protects against MITM better than TLS. There are things you can do to make it more difficult to hack your TLS connection though, for example you could use key pinning to make sure that your app will only accept a server with the certificate you expect. This would protect against an IT admin installing root certs on their users' devices, or against certificate authorities issuing fake certificates for your domain.
  - tonyhart7 1y ago
    Yeah this app maybe don't need that but for things like IoT running websocket connection for long time maybe I need that
- hiimkeks 1y ago
  Ah, the Zoom Gambit
  - tonyhart7 1y ago