libarchive VS 7z

29. October 2021 At this point Jia Tan pops up, and the first thing we see from him is an innocuous patch to the xz repository, and while a lot of people believe he started out trying his luck with another library also known as libarchive, this is not the case, I would bet it’s more of a backup looking at the dates, being that there are a few days in between as shown in this commit.

Potentially malicious commit by same author on libarchive: https://github.com/libarchive/libarchive/pull/1609

Full agreement, and with the addition of xpk¹/xfd² as natural extensions to that extensibility too. I see things like xfd supporting xz¹, and I'm simultaneously amazed that it exists and happy that I don't need to do xz {,de}compression on 68k ;)

I guess we have something similar-ish with libarchive⁴, but nobody(including me) has pushed the extra mile to get file dialogs to support random compression and decompression formats.

Beyond OT: I didn't realise how much stuff was still going on at aminet, but I love love LOVE that people are still dropping new car sets for Geoff Crammond's F1GP.

¹ http://aminet.net/package/util/pack/xpk_User

² http://aminet.net/package/util/pack/xfdmaster

³ http://aminet.net/package/util/pack/xfd_lzma.lha

⁴ https://www.libarchive.org/

I don't have a preview channel install handy to check, but apparently they're using libarchive so here's the full list assuming they expose everything it supports:

https://github.com/libarchive/libarchive/wiki/LibarchiveForm...

As announced at the Build conference back in May, this build adds native support for reading additional archive file formats using the libarchive open-source project such as

LibarchiveFormats · libarchive/libarchive Wiki · GitHub

Seems what they're using is BSD-liscensed: https://github.com/libarchive/libarchive/wiki

Looking back at this version history [1], there was perviously a gap of 3.5 years between releases (2011-2014). Skimming through the discussion forums, the 2.5yr gap between 19.00 and 21.07 was filled with a number of alpha and beta releases, eg 20.02 [2]. Version numbering seems to follow a consistent yy.## format since 2015.

[1] https://sourceforge.net/projects/sevenzip/files/7-Zip/

[2] https://sourceforge.net/p/sevenzip/discussion/45797/thread/9...

Also, unlike WinRAR, 7zip is open-source. Code mirror here: https://github.com/kornelski/7z

It's also open source.

AES is only as good as the KDF protecting the key. Looking at the github mirror of its code (updated march 2019), it seems to be using PBKDF2-SHA1 with 1,000 iterations. That's actually really bad because SHA1 is weak, and 1,000 iterations is very low.