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Re: Improving availability and guaranteeing integrity in ISO - internal sha1sums



On Sun, Jun 10, 2007 at 02:31:51PM +1000, David Timms wrote:
> I am not sure how you do that - how can you include inside a piece of 
> data a checksum that uses the data {including itself} to calculate the 
> checksum ?

Standard method is "zero the checksum area, compute the checksum,
write it".  At verification time, copy the checksum area in memory,
zero it and compute the checksum.

  OG.


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