From: "Gamblin, Todd" <gamblin2@llnl.gov>
To: "git@vger.kernel.org" <git@vger.kernel.org>
Subject: Commit SHA1 == SHA1 checksum?
Date: Sat, 5 Feb 2022 01:19:24 +0000 [thread overview]
Message-ID: <ED97E252-CABA-41BB-B18C-819A5EF305E3@llnl.gov> (raw)
Apologies if this has been asked before, but the closest thing I could find was this thread:
http://public-inbox.org/git/Pine.LNX.4.62.0504160519330.21837@qynat.qvtvafvgr.pbz/
That thread devolved into a discussion of the security of different hashes and didn’t answer my question.
I want to know when and where git *guarantees* that the snapshot I have checked out has the checksum that git says it does, or if it does at all.
The use case for this is for package managers. I work on Spack (http://github.com/spack/spack if you’re curious) and we download sources from tarballs and git repos (like many similar tools). For tarballs we require a sha256, and we use it to verify the tarball after download.
For git repos, we would like to require a commit sha1, provided that it’s basically as secure as downloading a tarball and checking it against a known sha1. So, if I `git clone` something, is the commit sha1 actually verified?
Thanks,
-Todd
PS: I know that sha1 has been declared “risky” by NIST and that folks should move away from it, and please be assured that we’re using sha256’s everywhere else. Here I really just want to know whether cloning a git repo at a particular commit is as secure as downloading a tarball and checking it against a sha1, not whether or not sha1 is secure.
next reply other threads:[~2022-02-05 1:19 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-05 1:19 Gamblin, Todd [this message]
2022-02-06 0:22 ` Commit SHA1 == SHA1 checksum? Philip Oakley
2022-02-06 9:00 ` Gamblin, Todd
2022-02-06 10:23 ` Johannes Sixt
2022-02-06 10:15 ` Junio C Hamano
2022-02-06 19:25 ` Philip Oakley
2022-02-06 20:02 ` Junio C Hamano
2022-02-06 21:33 ` Philip Oakley
2022-02-07 8:15 ` Gamblin, Todd
2022-02-07 13:15 ` Konstantin Ryabitsev
2022-02-07 21:08 ` Gamblin, Todd
2022-02-07 13:32 ` Konstantin Ryabitsev
2022-02-07 20:57 ` Junio C Hamano
2022-02-07 21:34 ` Konstantin Ryabitsev
2022-02-07 22:29 ` Gamblin, Todd
2022-02-07 22:46 ` Konstantin Ryabitsev
2022-02-08 6:23 ` Gamblin, Todd
2022-02-07 22:49 ` Junio C Hamano
2022-02-07 23:02 ` Konstantin Ryabitsev
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