Programming

17686 readers

233 users here now

Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!

Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.

Hope you enjoy the instance!

Rules

Follow the programming.dev instance rules
Keep content related to programming in some way
If you're posting long videos try to add in some form of tldr for those who don't want to watch videos

Wormhole

Follow the wormhole through a path of communities [email protected]

founded 2 years ago

MODERATORS

[email protected]

Unsigned Commits (blog.glyph.im)

submitted 11 months ago by [email protected] to c/[email protected]

24 comments fedilink hide all child comments

I'm curious to hear what the Lemmy programming community thinks of this!

The author argues against signing Git commits, stating that it adds unnecessary complexity to systems.
The author believes that signing commits perpetuates an engineering culture of blindly adopting complex tools.
The consequences of signing Git commits are likely to be subtle and not as dramatic as some may believe.

Archive link: https://archive.ph/vjDeK

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 1 points 11 months ago (3 children)

I've never understood the point of signing commits. If i can push a commit to a repo, then i can also add my own keys to the repo as well right? So malicious actor with my password can happily push signed commits?

Do many people actually sign commits?

[–] [email protected] 4 points 11 months ago (1 children)

I don't sign my commits.

Though I'll admit I'm not making a moral judgement, it was just a pain in the ass to setup last time I had the time to try it.

[–] [email protected] 3 points 11 months ago (1 children)

I don't sign my commits because I'm not going to verify anyone's commits.

[–] [email protected] 2 points 11 months ago* (last edited 11 months ago)

Yep. Same.

And of course there's a relevant XKCD:https://xkcd.com/1181/

[–] [email protected] 3 points 11 months ago

Unless they have access to your private key then there's no way they can sign code as you.

Alternatively yes, access to your password (and 2fa) would allow them the ability to add an ssh private key for you.

But that's irrelevant because the issue at hand is that I can make a commit to a repo that I have access to, but using your username, and there's no way to verify it wasn't you (actually there is but it requires some assumptions and is also dependent on the git hosting infrastructure)

However when you use signing, key 'A' may be able to access a repo but can't sign commits as key 'B', so you can't have the blame dropped on you for malicious commits (again, unless they also compromised your account/key)

[–] [email protected] 1 points 11 months ago

I use comment signing as some kind of a multifactor.

I have my signing key saved on YubiKey, so it's pretty difficult that an attacker could gain access to it.

However, you can still commit through git web browser, and usually have a session for it open when working. If I slipped up and someone got to my PC while I have github open (or managed to steal my session cookies somehow - i.e a rubber ducky driveby), his options are:

Commit without signing through SSH. I have ssh key password in my password manager that auto-locks after a minute, so that shouldn't happen, plus the commit wouldn't be signed since I have the key with me.
Commit something though the browser - he can't sign it.
Add SSH or a new signing key through the browser - I get immediately notified.

So, the end result should be that thanks to the signing mechanism, I should immediately know that something is wrong. Is it neccessary? Probably not, but I still think it's worth it, at least for me.

Now I'm wondering whether it wouldn't be better to have the ssh key on the Yubikey instead. Hmm. I did only discover commit signing later, and didn't have ybikey before, so it never occured to me.