[Cryptech Tech] Filesystem on keystore flash

Rob Austein sra at hactrn.net
Tue Aug 23 16:20:26 UTC 2016

At Tue, 23 Aug 2016 12:07:38 -0400, Rob Austein wrote:
> This scheme requires two meta data fields per pair of sectors: a
> serial number and a magic value.  General idea is that a sector is
> only valid if it has the right magic value (a constant, 0xdeadbeef
> would do, just can't be all zeros or all ones), so the magic value
> field is the last thing written to a sector.  If both sectors in a
> pair have the right magic value, the driver compares the serial fields
> according to the rules in RFC 1982: the sector with the higher number
> is the real one.

I expressed this (very) poorly: it's not two meta data fields per pair
of sectors, rather, it's two meta data fields per sector, with the
meta data fields each pair of sectors working together to provide the
desired behavior for that pair of sectors.  Sorry for any confusion.

More information about the Tech mailing list