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Re: How safe are signed git tags? Only as safe as SHA-1 or somehow safer?

From
Jonathan Nieder <jrnieder@gmail.com>
Date
Nov 25, 2014, 01:23 UTC
Message-ID
<20141125012359.GR6527@google.com>
In-Reply-To
<CACsJy8BMNXUinfK=YcJPkx98tYv_e40N0_mqqnzMLxDN6hkruA@mail.gmail.com>
Duy Nguyen wrote:
> The biggest obstacle is the assumption of SHA-1 everywhere in the
> source code (e.g. assume the object name always takes 20 bytes). Brian
> started on cleaning that up [1] but I think it's stalled. Then we need
> to deal with upgrade path for SHA-1 repos.
I think the biggest obstacle is the upgrade path. ;-)

If the upgrade path is taken care of, I won't mind writing and reviewing a coccinelle-generated patch to replace 20, 40, 21, 41, and so on with appropriate constants. Or we can take the first 20 bytes of a SHA-256, which is already supposed to have better security properties than SHA-1.

Another obstacle is hard-coded SHA-1s in tests.

Thanks, Jonathan

Previous: Duy NguyenNext: Duy Nguyen
Message 15 of 21 in “How safe are signed git tags? Only as safe as SHA-1 or somehow safer?”
  1. Patrick SchleizerNov 16, 2014
  2. Jeff KingNov 17, 2014
  3. Patrick SchleizerNov 21, 2014
  4. Jason PyeronNov 21, 2014
  5. Jeff KingNov 22, 2014
  6. Jeff KingNov 22, 2014
  7. Fedor BrunnerNov 25, 2014
  8. Duy NguyenNov 24, 2014
  9. Michael J GruberNov 24, 2014
  10. Duy NguyenNov 24, 2014
  11. Duy NguyenNov 25, 2014
  12. Jeff KingNov 24, 2014
  13. Nico WilliamsNov 24, 2014
  14. Duy NguyenNov 25, 2014
  15. Jonathan NiederNov 25, 2014
  16. Duy NguyenNov 25, 2014
  17. Stefan BellerNov 25, 2014
  18. Jeff KingNov 25, 2014
  19. Duy NguyenNov 25, 2014
  20. Junio C HamanoNov 25, 2014
  21. brian m. carlsonNov 25, 2014

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