Re: SHA1 collisions found

On Fri, Feb 24, 2017 at 04:42:38PM +0700, Duy Nguyen wrote:

On Thu, Feb 23, 2017 at 11:43 PM, Joey Hess [off-list ref] wrote:

quoted

IIRC someone has been working on parameterizing git's SHA1 assumptions
so a repository could eventually use a more secure hash. How far has
that gotten? There are still many "40" constants in git.git HEAD.

Michael asked Brian (that "someone") the other day and he replied [1]

quoted

quoted

I'm curious; what fraction of the overall convert-to-object_id campaign
do you estimate is done so far? Are you getting close to the promised
land yet?

So I think that the current scope left is best estimated by the
following command:

  git grep -P 'unsigned char\s+(\*|.*20)' | grep -v '^Documentation'

So there are approximately 1200 call sites left, which is quite a bit of
work.  I estimate between the work I've done and other people's
refactoring work (such as the refs backend refactor), we're about 40%
done.

As a note, I've been working on this pretty much nonstop since the
collision announcement was made.  After another 27 commits, I've got it
down from 1244 to 1119.

I plan to send another series out sometime after the existing series has
hit next.  People who are interested can follow the object-id-part*
branches at https://github.com/bk2204/git.
-- 
brian m. carlson / brian with sandals: Houston, Texas, US
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