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Do people expect that Instagram can't read their Instagram private messages? I don't think people expect that. And E2EE is not nearly as cheap as the HN crowd l
by chadgpt2 4mo ago
Do people expect that Instagram can't read their Instagram private messages? I don't think people expect that. And E2EE is not nearly as cheap as the HN crowd likes to pretend—how do those devices get those keys if not through a central service? Especially if one of them is a web browser?
- onemoresoop 4mo agoOk, so drop all pretense then and blatantly scavenge through private conversations? Then take whatever from there and maybe sell it to highest bidder?
- ryandrake 4mo agoI would expect any message facilitated by a company's software, and going through that same company's servers to be compromised.
- mrexcess 4mo agoThe answer to most everyone question you’re asking is just, “public key cryptography”. It’s kind of disheartening to me that such basic 1990s tech as implemented by Phil Zimmerman is now obscure enough to merit questions like this. Both parties exchange public keys through the central service. Only the possessor of the respective (on device, Secure Enclave ideally) private keys can decrypt the messages encrypted to the public key. The process can also work in reverse, encrypting with the private key so only holders of the public key can decrypt: this is called “signing”.
- feurio 4mo agoAnd how does one verify that the public key received belongs to the intended party, rather than a mitm? If the answer is blind trust in a third party that runs the messaging service then I suspect that you can guess what the people asking those questions are really asking.
- danparsonson 4mo agohttps://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange https://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exc... If Meta are turning it off then I guess it's reasonable to assume that there is something to turn off.
- tardedmeme 4mo agoHow would the keys get stored in the user's private browsing window? Do they lose all chat history when they log in on a private browsing window and then close it?
- danparsonson 4mo agoI don't know the technical details of that for sure, but I think the answer is that keys and chat history are stored on-device only; for example you lose your WhatsApp history if you don't restore a backup when moving to a new phone. If a messaging app is showing you message history in a private browsing window then perhaps the encryption key for that history is derived from your password or something like that; that can be done locally so that all the server ever sees is encrypted data.
- tardedmeme 4mo agoIf you log in to the app on one phone and then in a web browser should you still be able to see your messages in the web browser?
- danparsonson 4mo agoSorry do you mean, that's how it works now, or, that's how you think it should work? Are you talking about Instagram or WA or something else? edit: misread your message; if you have two sessions active at the same time, then yes I would expect both sessions to receive the same messages.
- rileymat2 4mo agoThe fly in the ointment is that they control the software and updates to that closed software so can short circuit that with appropriate pressure.
- Terr_ 4mo agoThrowing this on the "brainstorm if we had an ideal legislative world" pile: Stealing a user's private key should be a felony, even if it hasn't (yet) been abused for anything. The tricky part is keeping it from being "permitted" by a crappy contract of adhesion. Banning it entirely would make it very difficult to buy/sell backup services...
- mrexcess 4mo agoLegal solutions to technical problems are always dubious, especially when privacy against government surveillance is the problem.
- Terr_ 4mo agoAh, but not nearly as dubious as technical solutions to legal problems...
- mrexcess 4mo agolol honestly, I think a little on the contrary. If we can make a thing impossible technically, the law defers to that. One thing the government really can’t do easily in Western countries is forcing a company to add features or change core functionality.
- Terr_ 4mo agoI'd say those are legal barriers, rather than technical barriers. For example, suppose the government demands constant access to your core database. You don't need to invent any new algorithms for that, you might just make an SQL user and a firewall exception and call it a day. Similarly, If you have a messaging client, you don't need complex R&D to steal the "end-to-end" keys.
- traderj0e 4mo agoNo, it's not at all this simple. This is why so many "e2ee" apps like Telegram are bogus, they ended up prioritizing UX over security because there are many places where you can't pick both.
- mrexcess 4mo agoWebs of trust based on OOB key verification and signing, or centralized trust authorities are the two primary models I’m aware of. I’ve always been enamored of the idea of DNS as a back end protocol to enable the former largely decentralized solution. Bob looks up Alice and receives her key from Alice’s namespace within the DNS hierarchy, along with her trust claims. David then looks up Alice’s key within her namespace, sees a reference to endorsement by Bob, and can validate this by querying Bob’s namespace. David can also issue non-authoritative queries about Alice’s key to Bob’s DNS servers, ensuring that there is no mismatch between the query response received by Bob and the one received by David. If Mallory manages to compromise Alice’s DNS, but not Bob’s, the result is a mismatch in query responses that both Bob and David can thus detect. At scale, a MITM compromising a system like this would be difficult without compromise of a large number of independent namespaces, increasing the likelihood of detection via the non-authoritative queries. The missing component in this arrangement is cryptographic security of DNS, which I cynically suspect is why the DNSsec working group was comprised of the usual suspects and eventually produced a protocol without query encryption. It could still be layered on by a protocol extension, however.
- traderj0e 4mo agoIn practice it's possible to make a system that's hard to mitm if users are diligent. WhatsApp publishes a public record of hashes of the keys. If both sides check that record against their local keys, it's hard for WhatsApp to present different versions to each. Though that's a more recent development. The harder part that Instagram is most likely concerned about is getting low-effort users to keep their private keys safe without losing them.
- torben-friis 4mo ago>Do people expect that Instagram can't read their Instagram private messages? I don't think people expect that. A deeper question is why we reached a point where people can't reasonably expect their communication to not be spied on.
- dmbche 4mo agoPRISM?
- Slash65 4mo agoPeople, or at least Americans, didn’t care in 2012 when the Snowden reveal happened. We’ve been at that point for over a decade now.
- 2ndorderthought 4mo agoConsidering the average person thinks that opening websites in incognito means no one knows they visited them, I would agree.
- sharyphil 4mo ago"Be wary of malicious software that tracks your keystrokes in exchange for free smileys"
- lovich 4mo agowere like 20 years past that, at the very least 10 years with Snowden. The people have spoken, caring about your communications not being spied on puts you in the minority. I mean like, just look at social media. You have tons of people who not only don't care about being spied on, they actively document everything for more views.
- traderj0e 4mo agoExactly. E2EE comes with UX consequences that you can't just bolt on later. There might be something to be outraged about, but this alone isn't it.