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SHA1 hash safety

From
DLDavid Lang <david.lang@digitalinsight.com>
Date
Apr 16, 2005, 12:24 UTC
Message-ID
<Pine.LNX.4.62.0504160519330.21837@qynat.qvtvafvgr.pbz>

this issue was raised a few days ago in the context of someone tampering with the files and it was decided that the extra checks were good enough to prevent this (at least for now), but what about accidental collisions?

if I am understanding things right the objects get saved in the filesystem in filenames that are the SHA1 hash. of two legitimate files have the same hash I don't see any way for both of them to exist.

yes the risk of any two files having the same has is low, but in the earlier thread someone chimed in and said that they had two files on their system that had the same hash..

David Lang
-- 
There are two ways of constructing a software design. One way is to make it so simple that there are obviously no deficiencies. And the other way is to make it so complicated that there are no obvious deficiencies.
  -- C.A.R. Hoare
Next: Ingo Molnar
Message 1 of 30 in “SHA1 hash safety”
  1. David LangApr 16, 2005
  2. Ingo MolnarApr 16, 2005
  3. David LangApr 16, 2005
  4. Brian O'MahoneyApr 16, 2005
  5. C. Scott AnanianApr 16, 2005
  6. Petr BaudisApr 16, 2005
  7. C. Scott AnanianApr 16, 2005
  8. David LangApr 16, 2005
  9. Paul JacksonApr 16, 2005
  10. Martin MaresApr 16, 2005
  11. David A. WheelerApr 17, 2005
  12. Theodore Ts'oApr 18, 2005
  13. ross@lug.udel.eduApr 16, 2005
  14. Horst von BrandApr 17, 2005
  15. Brian O'MahoneyApr 18, 2005
  16. C. Scott AnanianApr 18, 2005
  17. Paul JacksonApr 16, 2005
  18. Brian O'MahoneyApr 16, 2005
  19. Andy IsaacsonApr 18, 2005
  20. C. Scott AnanianApr 18, 2005
  21. David MeybohmApr 19, 2005
  22. C. Scott AnanianApr 19, 2005
  23. David MeybohmApr 20, 2005
  24. David LangApr 16, 2005
  25. Paul JacksonApr 16, 2005
  26. David LangApr 16, 2005
  27. TkilApr 17, 2005
  28. Paul JacksonApr 17, 2005
  29. TkilApr 17, 2005
  30. Paul JacksonApr 17, 2005

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