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LLMs won't break symmetric crypto

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Re: LLMs won't break symmetric crypto

#21

Post by retrac »

sghiassy wrote: post #6
dadrian wrote: post #4

Earlier quoted context omitted.

RSA is asymmetric crypto. This article is about symmetric cryptography. I expect LLMs will advance state of the art in factoring algorithms, considerably.

Thank you I guess I only know asymmetric cryptography. I should learn more about symmetric… Anyone care to boil it down for me :) Edit: Isn’t this just advanced static analysis of any code base?

A symmetric cipher is: ciphertext = data XOR key. XOR is reversible: plaintext = ciphertext XOR key.

If the key is a set of truly random numbers the same size as the ciphertext, then this is a one-time pad, and it is truly secure in the information theory sense. Nothing other than knowing the original randomly selected key values can decode the ciphertext.

But of course, it's hard to come up with terabytes of random numbers at the drop of a hat, and to share them securely with the other party. So symmetric ciphers use pseudo-random generation techniques, to iterate through many pseudo-random keys based on one original key. With PRNGs the "randomness" may have patterns and that is the opening for a break in the crypto.

Re: LLMs won't break symmetric crypto

#23

Post by PlasmaPower »

sghiassy wrote: post #14
OJFord wrote: post #10

Earlier quoted context omitted.

I think the thing most of us missed in dismissing GPT 2-3 as 'next word in sentence predictors' was that recursively this allows something resembling thinking, 'reasoning'. LLMs are capable not just of calculating the most likely next word from a prompt according to a corpus of training text, but of doing so & feeding back into themselves, the most likely word now based not only on the corpus but on the basic predict…

I’m with ya I’ve even heard arguments that prediction is consciousness. But using a Language-Model to break cryptography is still a stretch for me. From the little I know, cryptography uses information theory to make sure that reversing the equation (aka finding the passowrd) is predictably impossible, given current compute standards for the foreseeable future (disregard quantum computer here though :) they’re not LL…

The oversight in your thinking is that we have no proofs about how much computation is needed to break cryptography. For all we know, it could be possible to break all modern cryptosystems in under a second on a computer from a decade ago with the right algorithms.

This is how cryptography has been broken in the past: not just advances in the amount of compute we can do, but exponential speedups in the algorithms to break them. While I agree with the author of this post that modern cryptosystems are very secure and LLMs are not currently near breaking them, I don't think it's unreasonable to consider that if LLMs continue to get exponentially smarter they may make strides in cryptanalysis that we had never considered and break cryptography in unexpected ways. After all, many past cryptography breaks have come from previously unknown methods of cryptanalysis.

Re: LLMs won't break symmetric crypto

#24

Post by fluoridation »

sghiassy wrote: post #18
fluoridation wrote: post #17

Earlier quoted context omitted.

Very, very briefly, most symmetric algorithms are block ciphers, meaning that their input are blocks of a fixed length in bits (plus a key), and their output is another block of the same length. Ideally, a block cipher with its key produces a random permutation of the input space into the output space, thus diluting the information and dramatically increasing (ideally maximizing) the entropy; what that means is that…

Thank you I wish I knew more in this domain. It almost sounds like hashing with a salt

It pretty much is, except it's reversible. At the block level it meets the cascading requirement, and you can set it up to expand the output arbitrarily by padding the input with zeroes (thus also turning it into a PRNG).

Re: LLMs won't break symmetric crypto

#25

Post by danielmarkbruce »

This is kind of a stupid argument. How about make a slightly stronger claim like "models won't break symmetric crypto" ? I mean, language models aren't even trained to break symmetric crypto. There is not good reason to think they will. It seems possible to train a large model to do it though.

Re: LLMs won't break symmetric crypto

#26

Post by sghiassy »

PlasmaPower wrote: post #23
sghiassy wrote: post #14

Earlier quoted context omitted.

I’m with ya I’ve even heard arguments that prediction is consciousness. But using a Language-Model to break cryptography is still a stretch for me. From the little I know, cryptography uses information theory to make sure that reversing the equation (aka finding the passowrd) is predictably impossible, given current compute standards for the foreseeable future (disregard quantum computer here though :) they’re not LL…

The oversight in your thinking is that we have no proofs about how much computation is needed to break cryptography. For all we know, it could be possible to break all modern cryptosystems in under a second on a computer from a decade ago with the right algorithms. This is how cryptography has been broken in the past: not just advances in the amount of compute we can do, but exponential speedups in the algorithms to…

Can someone more knowledgeable than me comment on this.

I thought, that Information Theory could mathematically predict the computational challenge of factoring one massive number into its two original primes?

Is that not true? If you have just a random number (aka public key) can you just LLM your way to the private key??!?

Re: LLMs won't break symmetric crypto

#27

Post by catlifeonmars »

danielmarkbruce wrote: post #25

This is kind of a stupid argument. How about make a slightly stronger claim like "models won't break symmetric crypto" ? I mean, language models aren't even trained to break symmetric crypto. There is not good reason to think they will. It seems possible to train a large model to do it though.

Agreed that many of the articles claims are a bit weak. One point is reasonably strong though: symmetric crypto may not be breakable (battle tested).

Re: LLMs won't break symmetric crypto

#30

Post by jerf »

sghiassy wrote: post #14
OJFord wrote: post #10

Earlier quoted context omitted.

I think the thing most of us missed in dismissing GPT 2-3 as 'next word in sentence predictors' was that recursively this allows something resembling thinking, 'reasoning'. LLMs are capable not just of calculating the most likely next word from a prompt according to a corpus of training text, but of doing so & feeding back into themselves, the most likely word now based not only on the corpus but on the basic predict…

I’m with ya I’ve even heard arguments that prediction is consciousness. But using a Language-Model to break cryptography is still a stretch for me. From the little I know, cryptography uses information theory to make sure that reversing the equation (aka finding the passowrd) is predictably impossible, given current compute standards for the foreseeable future (disregard quantum computer here though :) they’re not LL…

I think you misunderstand. The idea is not that one feeds a cryptographic text to LLMs and they crack it. The idea is that one feeds a cryptographic algorithm to an LLM and they break it somehow. Bear in mind that cryptographers consider a "break" anything that reduces the strength of an algorithm, but that doesn't mean that it is practical to use the given "break" to obtain even one plaintext, let alone obtain them all.
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