[openssl-users] Comments on the recent OpenSSL 3.0.0 specification (Monday 2019-02-11)

[Tomas Mraz]

On Fri, 2019-02-15 at 11:23 +0000, Matt Caswell wrote:
> 
> On 15/02/2019 03:55, Jakob Bohm via openssl-users wrote:
> > yout - but this is useful input.
> 
> > 
> > FIPS-specific issues:
> > 
> > - The checksum of the FIPS DLL should be compiled into the FIPS-
> >  capable OpenSSL library, since a checksum stored in its own file
> >  on the end user system is too easily replaced by attackers.  This
> >  also implies that each FIPS DLL version will need its own file
> > name
> >  in case different applications are linked to different libcrypto
> >  versions (because they were started before an upgrade of the
> > shared
> >  libcrypto or because they use their own copy of libcrypto).
> 
> This is not an attack that we are seeking to defend against in 3.0.0.
> We
> consider the checksum to be an integrity check to protect against
> accidental
> changes to the module.

+1 to Matt. The integrity check of FIPS standard was never ment to be a
mitigation against active attacks. Its purpose always was just
protection against inadvertent HW or SW errors.

Building the checksum into a binary overly complicates things and it is
not worth the hassle as it would not protect against active attacks
either, it would just complicate them a little.

> 
> > - If possible, the core or a libcrypto-provided FIPS-wrapper should
> >  check the hash of the opensslfips-3.x.x.so DLL before running any
> >  of its code (including on-load stubs), secondly, the DLL can
> >  recheck itself using its internal implementation of the chosen MAC
> >  algorithm, if this is required by the CMVP.  This is to protect
> > the
> >  application if a totally unrelated malicious file is dropped in
> >  place of the DLL.
> 
> As above - this is not an attack we are seeking to defend against.

+1

-- 
Tomáš Mráz
No matter how far down the wrong road you've gone, turn back.
                                              Turkish proverb
[You'll know whether the road is wrong if you carefully listen to your
conscience.]