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Comment by zmmmmm | Hacker News Reader

Of all the arguments presented I'm surprised to see absent the one that seems most obvious to me: encryption is just math, there's no way to actually ban it. If criminals think their conversations are going to be detected they aren't going to just say "oh well let's not crime now". They are going to simply spin up their own e2e encrypted channels. The software is nearly trivial, the technical barriers are very low - it's hard to think why it won't happen.

So then what? They start outlawing encryption altogether? knowledge of math? How would you claw back all the public and freely available software that people can already use to encrypt messages to each other?

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> They start outlawing encryption altogether?

This is the direction places like the UK have gone in, yes. Can't decrypt something? Then we assume it is illegal content.

Steganography it is then. Can't assume something is illegal, if it's hidden.

Sure you can. For example, UK will jail you if you refuse to disclose a cryptographic key for something encrypted that the court wants to see, so long as the judge is convinced that you know it. I could easily see that extending to steganography: "there's no rational justification for you to have this file, and statistical analysis patterns show that it likely has a steganographic payload".

"Sir, those are just internet memes I've been sharing with a friend of mine"

The whole point of this technique is that with sufficiently low information density the data is not recoverable unless you know what you're looking for, because it's indistinguishable from noise.

> "Sir, those are just internet memes I've been sharing with a friend of mine"

"I don't believe you, so now you're going to be in the locker for contempt of court until you provide law enforcement access to this critical evidence."

"What evidence? This is normal noise associated with lossy compression. Have an expert look at it - they'll confirm what I've said."

> "Sir, those are just internet memes I've been sharing with a friend of mine"

Then it is reasonable to assume that you can just show us these internet memes?

Of course, because I can bet on the fact that no one will find anything having just those images.

Again: the signal is below the noise floor. Unless you really know what to look for, you'll just find noise. Whoever seizes these files would have to at least know the specific method used, particularly if the content is also encrypted.

Take for an example JPEG as a vessel for steganographic content: the image is divided into 8x8 pixel chunks. If you encode just one bit of entropy in each chunk, a 320x240 image will yield 1200 bits, so 150 ASCII characters. Mangle it with a one-time pad for good measure so that it actually looks like noise. How did that noise get there? Well, it's lossy compression your honor.

There are so many ways to encode that one bit in such a large piece of information that authorities are better off drugging, bribing or torturing you or whoever was the recipient of that message than trying to decode it.

I mean, not just the UK - it eventually changed in the US, but anything deemed too strong to crack was classified as a munition for a while in the 90s and 00s, and some things are still banned from being shipped to some places -

https://en.wikipedia.org/wiki/Export_of_cryptography_from_th...

"It's just math, you can't ban it" has never been true.

https://en.m.wikipedia.org/wiki/Illegal_number

> Any image file or an executable program can be regarded as simply a very large binary number.

This had never occurred to me before but is totally obvious in hindsight. An interesting corollary is that, given an infinite natural number space, all programs that have ever and will ever exist can be found as a single point on this natural number plane. The larger the number, the more complex the program. What else is emergent from this property?

Sounds like The Library of Babel:

https://en.wikipedia.org/wiki/The_Library_of_Babel

https://github.com/philipl/pifs

I'm sure many core proponents of Chat Control would like to also make it illegal to "hide" from scanning by applying your own encryption (and, even if not caught directly, it would add to the list of crimes someone might be charged with) but that large of a change probably puts it too far outside the Overton Window of today in a single push.

People have been selectively "banning math" for decades -

https://en.wikipedia.org/wiki/Export_of_cryptography_from_th...

They don't even need to spin up their own channels, they can just continue to use existing channels and encrypt their messages.

I mean, if youre in the business of CSAM surely you don't mind encrypting a zip and emailing it or putting it on Google drive or whatever. Its trivial, requires next to zero technology knowledge.

Its inconvenient, sure, which is why we don't currently do that. But I'm sure the CSAM distributors don't care. Why would they?

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