RE: [PATCH v4 1/1] use crc32 instead of md5 for hibernation e820 integrity check

From: David Laight
Date: Fri Apr 09 2021 - 12:56:16 EST


From: Chris von Recklinghausen
> Sent: 08 April 2021 11:46
>
> Suspend fails on a system in fips mode because md5 is used for the e820
> integrity check and is not available. Use crc32 instead.
>
> Prior to this patch, MD5 is used only to create a digest to ensure integrity of
> the region, no actual encryption is done. This patch set changes the integrity
> check to use crc32 instead of md5 since crc32 is available in both FIPS and
> non-FIPS modes.
>
> Note that the digest is only used as an integrity check. No actual encryption
> is done.

If crc32 is good enough, would a 1's compliment sum be good enough?
It is likely to be faster to calculate and not need special
functions be built into the kernel at all.

David

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