All git repos have "repositoryversionformat", you can bump it. And nobody is going to complain about having to do a fresh clone, given what just happened.
"Not having security eggs in one basket" is exactly irrelevant here. Upgrading the hash does not make the other parts of the system weaker, and should have been done years ago. Yes, SHA2 will also become weak eventually - so then you bump it again. The point is to choose the best one for that time of history, which he has been resisting doing for years, based on bullshit pseudo-arguments about "trust".
No, git uses hashes in the same way that most other security system use hashes. The "trust" comes at a different point of the system. No hashes by themselves are "trusted" anywhere by any system. Git is not special in this regard. I repeat, Linus is talking horseshit and this horsehit argument is unfortunately getting repeated and spread around because of his position in the community.
I said the use of GPG is pointless, not SHA1 pointers, especially given his "trust" arguments. To exaggerate slightly, just to show you the point: it's like locking up a crappy lock (SHA1) inside a really secure safe (GPG). But this crappy lock is what opens up the real safe where your actual money is kept (the tree objects). And then we have Linus talking shit on the side saying the keys are not so important, but what he really gets security from is his trust in the delivery company that ships the safe around.
> Yes, SHA2 will also become weak eventually - so then you bump it again.
I disagree here. I doubt SHA2 or any modern hash will become weak within our lifetime. JP Aumasson, who is one of the experts of the field, agrees with me on that:
https://twitter.com/veorq/status/834872988445065218
It's funny because in that Twitter thread this[0] is linked:
Reactions to stages in the life cycle of cryptographic hash functions
Stage | Expert reaction | Programmer reaction | Non-expert ("slashdotter") reaction
---------------------+---------------------------------------------+-------------------------------------------------+----------------------------------------
... | ... | ... | ...
General acceptance | Top-level researchers begin serious work on | Even Microsoft is using the hash function now | Flame anyone who suggests the function
| finding a weakness (and international fame) | | may be broken in our lifetime
Just to be clear: I don't doubt JP Aumasson's reasons to believe so. I doubt yours because as far as I can tell it's basically argument from authority ("JP Aumasson said so!")
"Not having security eggs in one basket" is exactly irrelevant here. Upgrading the hash does not make the other parts of the system weaker, and should have been done years ago. Yes, SHA2 will also become weak eventually - so then you bump it again. The point is to choose the best one for that time of history, which he has been resisting doing for years, based on bullshit pseudo-arguments about "trust".
No, git uses hashes in the same way that most other security system use hashes. The "trust" comes at a different point of the system. No hashes by themselves are "trusted" anywhere by any system. Git is not special in this regard. I repeat, Linus is talking horseshit and this horsehit argument is unfortunately getting repeated and spread around because of his position in the community.
I said the use of GPG is pointless, not SHA1 pointers, especially given his "trust" arguments. To exaggerate slightly, just to show you the point: it's like locking up a crappy lock (SHA1) inside a really secure safe (GPG). But this crappy lock is what opens up the real safe where your actual money is kept (the tree objects). And then we have Linus talking shit on the side saying the keys are not so important, but what he really gets security from is his trust in the delivery company that ships the safe around.