385
submitted 2 months ago by pnutzh4x0r@lemmy.ndlug.org to c/linux@lemmy.ml

There's been some Friday night kernel drama on the Linux kernel mailing list... Linus Torvalds has expressed regrets for merging the Bcachefs file-system and an ensuing back-and-forth between the file-system maintainer.

you are viewing a single comment's thread
view the rest of the comments
[-] LemmyHead@lemmy.ml -4 points 2 months ago

Encryption and compression don't play well together though. You should consider that when storing sensitive files. That's why it's recommended to leave compression off in https because it weakens the encryption strength

[-] nous@programming.dev 5 points 2 months ago

How does that work? Encryption should not care at all about the data that is being encrypted. It is all just bytes at the end of the day, should not matter if they are compressed or not.

Disabling compression in HTTPS is advised to prevent specific attacks, but this is not about compression weakening encryption directly. Instead, it’s about preventing scenarios where compression could be exploited to compromise security. The compression attack is used to leak information about the content of the encrypted data, and is specific to HTTP, probably because HTTP has a fixed or guessable structure.

[-] nous@programming.dev 4 points 2 months ago* (last edited 2 months ago)

Looks to be an exploit only possible because compression changes the length of the response and the data can be injected into the request and is reflected in the response. So an attacker can guess the secret byte by byte by observing a shorter response form the server.

That seems like something not feasible to do to a storage device or anything that is encrypted at rest as it requires a server actively encrypting data the attacker has given it.

We should be careful of seeing a problem in one very specific place and then trying to apply the same logic to everything broadly.

[-] pimeys@lemmy.nauk.io 4 points 2 months ago

It is only in TLS where you have to disable compression, not in HTTP.

https://security.stackexchange.com/questions/19911/crime-how-to-beat-the-beast-successor/19914#19914

Could you explain how a CRIME attack can be done to a disk?

[-] nous@programming.dev 4 points 2 months ago

There is also the BREACH which targets gzip/deflate compression on http as well. But also, don't see how that affects disk encryption.

[-] LemmyHead@lemmy.ml 2 points 2 months ago

I can't explain, perhaps due to my limited knowledge about the subject. I understood that compression was a weakening factor for encryption years ago when I heard about it. Always good to do your own research in the end 🙃

this post was submitted on 24 Aug 2024
385 points (99.0% liked)

Linux

48143 readers
605 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago
MODERATORS