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Joined 3 years ago
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Cake day: July 2nd, 2023

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  • Yes, subpoena was poorly worded. NSL is more likely. But still it is a time-forward threat, which means there is value while the server is or was accepting sealed sender.

    And I wasn’t suggesting timing attack is required to defeat sealed sender. I was, on the contrary, pointing out that was a threat even with sealed sender. Though that is non-trivial, especially with CGNAT.

    So in summary. You’re right. Sealed sender is not a great solution. But it is a mitigation for the period where those messages are being accepted. A better solution is probably out there. I hope somebody implements it. In the meantime, for somebody who needs that level of metadata privacy, Signal isn’t the solution; maybe cwtch or briar.


  • Sure. If a state serves a subpoena to gather logs for metadata analysis, sealed sender will prevent associating senders to receivers, making this task very difficult.

    On the other hand, what it doesn’t address is if the host itself is compromised where sealed sender can be disabled allowing such analysis (not posthoc though). This is also probably sensitive to strong actors with sufficient resources via a timing attack.

    But still, as long as the server is accepting sealed sender messages the mitigation is useful.


  • Don’t mistake me for saying you’re wrong. I agree with you, mostly. But sealed sender isn’t theater, in my view. It is a best effort attempt to mitigate one potential threat. I think everybody would like that solved but actually solving it isn’t easy as I understand it. Maybe not intractable, but if you have a solution, you can implement it. That is one of the things I like about free software.

    In any case, I’m only saying Signal is good for a subset of privacy concerns. Certainly not that it is the best solution in all cases.


  • It isn’t a meme. It is a fact of modern cryptography in many settings. For example TLS, which is a huge bulk of the traffic, guarantees again privacy not anonymity. I’m not saying one shouldn’t care about metadata privacy. Every communication one engages in requires risk benefit analysis. If your threat modeling shows that for a given message, anonymity is required, then signal, and nearly every single other protocol out there is insufficient.

    That doesn’t mean TLS or lib signal, or any other cryptographic tool is not useful, especially in conjunction with other tools.

    There are many cases where I want my messages to be private and the cost of entry for the message receiver to be low. Signal is great for that. But I’m not saying no other tools should be considered, just that signal is good at what it does.



  • Cool strawmen; I didn’t say any of that. Signal protocol is awesome for privacy, not anonymity. Maybe I don’t have half a brain, but I happen to think the double ratchet implementation is an impressive piece of tech. Maybe I’m as dumb as your fever dream, but compromised exits doesn’t make tor any less of an achievement. Though i2p is also superb. I guess my brain is too weak to understand why those statements are mutually exclusive.





  • Okay fair enough, but that is at least slightly different than saying Proton isn’t FOSS, but I understand.

    They have a pretty good FOSS standing and audits for software they distribute. While that doesn’t make it easy to host privately, it does make it trivial to see how data is shipped to their servers.



  • I pay for Proton and I’m very happy with it. I think they need Contact phone integration but otherwise rock solid products. I don’t like the CEO, but generally I hate them all, so I try not to think about that. Their full suite of products has treated me well for a few years now.

    Not at all saying the alternatives aren’t better, just sharing my experience.



  • No. You’re the only one I see implying there are no cases where data is private outside a VPN. Strictly speaking, if you need only the data across a connection to be private TLS is sufficient. Who is implying that is a complete threat model. You are building more and more strawmen against which to argue, but it really just sounds silly. I’m a professional that has been in the industry for decades, so your dick waving contest just doesn’t move me.

    Yes, a more complete risk analysis in many cases may show that you’d like the host one is reaching to also be private, but nobody is saying such a situation doesn’t exist; you’re barking at the moon.



  • They didn’t say they don’t value privacy; a bit of a strawman. Most connections are private even if not anonymous. TLS is sufficient for many uses. Knowing this allows one to be discerning about when a VPN is more useful.


    Actually maybe I misread your intent. On second glance, looks like you might be yes-and’ing.