>>"something they have neither the ability nor the desire to do."
>100% they could add client side scanning, why do they think its impossible?
I think you've misread that sentence. It's saying that they don't have the ability right now, as-in this is not a feature they've written in their software, and that further they do not wish to do so (in the same way that Apple did not want to write a backdoor for the FBI previously). Obviously as a matter of programming of course backdoors can be written and have been. But software developers don't want to be forced at gun point to do so like the EU proposes, which seems perfectly understandable.
And fwiw with open source software it actually would be arguable that they "don't have the ability" on a more technical level since that couldn't actually be enforced on the users and the EU's jurisdiction ends at its borders. Obviously many of the most popular messengers are proprietary, but not all. And even for the proprietary vendors that probably does factor into their arguments, as it'd put them at a commercial disadvantage.
Perhaps its more along the line of it being impossible to have privacy if privacy invading scanning is required. Its impossible to have secure encryption if there is a requirement to be not secure so that every message can be read by any government that wants to.
What apps can access can be restricted by the OS.
All you need to do to avoid it would be to encrypt outside the app, something most people would not bother to do, but criminals would be motivated to do.
whats that got to do with whatsapp scanning the photo youre about to send?
1. Client-side scanning of the content that is externally encrypted is impossible. So if you are a criminal, you just don't share the photo, you share the encrypted file to circumvent this restriction.
2. Reliable client-side scanning of images is impossible (you cannot download illegal content to client devices for exact matches, so it will be only signatures and collisions are possible), so there will be false positives that will be reported, which will inevitably result in violation of privacy, possibly persecution etc.
1. Of course its possible, youd just get back encrypted data. This doesnt make it impossible
2. You mean "Reliable classification of client-side scanned images is impossible", although you dont actually define reliable. This is besides the point, Im not talking about the actually feasibility of this on a political level, Im asserting a specific technical point that client-side scanning is 100% possible for e2e apps
That specific technical point is trivial and is not worth discussing it. Of course you can „scan“ a data stream, but what’s the point if it doesn’t yield any meaningful results?
The only acceptable scanning process here is the one that produces only true positives, no collateral damage. This is what I call reliable.
> The only acceptable scanning process here is the one that produces only true positives, no collateral damage. This is what I call reliable.
well then reliability is impossible, you must accept errors
> well then reliability is impossible, you must accept errors
Nobody should accept errors. Client-side scanning simply must not happen. It’s mathematically dumb idea.
1. If the client application is hashing ciphertext, its hash will not match any known offending hashes, even if the plaintext is a known file.
I don't understand why someone would go through the trouble of using WhatApp to pass around separately-encrypted files instead of using anything else, though.
2. It's also "technically possible" to do the scanning server-side, on the encrypted stream, and flag anything that by chance matches a known hash.
Cool are you happy to run a hash of all your files and if it matches a certain hash you're accused of a crime?
BTW the hash is a CRC32 one
Wait until you get accussed of shit because of false positive. Happened in the story with Google and photo of boy to a doctor, Google refused to revoke it's automated crap even when false positive was proven.
They can't do it without false positives stochastically decrypting perfectly legal conversations without a warrant or any sort of due process. Of course, the EU elites don't care, but the leadership of Signal/etc obviously do.
> Of course, the EU elites don't care
Oh they do. They are excempted.
Source or is that something you imagined?
Only that last link is relevant to the question, for those who want to read about the proposed exemptions.