Re: SHA1 collisions found
- From
Jacob Keller <jacob.keller@gmail.com>
- Date
- Feb 25, 2017, 02:26 UTC
- Message-ID
- <CA+P7+xqyaWHBxug0BPdCgDVJBLtsvUxbgfgy1uJcoGf3q6xMQg@mail.gmail.com>
- In-Reply-To
- <20170225012100.ivfdlwspsqd7bkhf@sigill.intra.peff.net>
On Fri, Feb 24, 2017 at 5:21 PM, Jeff King <peff@peff.net> wrote:
Show 20 quoted lines
> On Fri, Feb 24, 2017 at 05:00:55PM -0800, David Lang wrote: > >> On Fri, 24 Feb 2017, Jeff King wrote: >> >> > >> > So I'd much rather see strong rules like: >> > >> > 1. Once a repo has flag-day switched over to the new hash format[1], >> > new references are _always_ done with the new hash. Even ones that >> > point to pre-flag-day objects! >> >> how do you define when a repo has "switched over" to the new format in a >> distributed environment? > > You don't. It's a decision for each local repo, but the rules push > everybody towards upgrading (because you forbid them pulling from or > pushing to people who have upgraded). > > So in practice, some centralized distribution point switches, and then > it floods out from there.
This seems like the most reasonable strategy so far. I think that trying to allow long term co-existence is a huge pain that discourages switching, when we actually want to encourage everyone to switch someone has switched.
I don't think it's sane to try and allow simultaneous use of both hashes, since that creates a lot of headaches and discourages transition somewhat.
Thanks, Jake