But this proposal wouldn't work correctly for
case:

PermitRootLogin yes
PermitRootLogin no

in the config file. Ignore the proposal (I will came
with another version yet).

Thanks, Jan.
--
Jan iankko Lieskovsky / Red Hat Security Technologies Team

----- Original Message -----
> From: "Jan Lieskovsky" <[email protected]>
> To: [email protected]
> Sent: Friday, November 22, 2013 1:08:54 PM
> Subject: Re: [PATCH] [RHEL6] Fix OVAL check for '3.4.3.g. Disable SSH Root    
> Login' rule
> 
> Hello Leland,
> 
>   thank you for your review.
> 
> > Shouldn't the check_existence attribute be "at_least_one_exists" rather
> > than
> > "only_one_exists"?
> 
> I am not sure this would be necessary / the correct scenario. See below.
> 
> >  Surprisingly, sshd does not complain about multiple
> > PermitRootLogin lines in /etc/ssh/sshd_config.
> 
> Yes (interesting btw.). Looks sshd is recognizing value of the first option
> occurrence as the setting to be applied, ignoring the rest (so having
> 
>   PermitRootLogin no [PRL]
>   PermitRootLogin yes
> 
> would still deny the remote SSH logins for root).
> 
> The current proposal returns correct results for all scenarios like
> (having 'PRL no' two times in the config, 'PRL no, PRL yes, PRL no',
> etc. in the config AFAICT).
> 
> check_existence=only_one_exists succeeds / works properly also for the
> case there are multiple instances of "PRL no" present in the config file,
> because we are interested only in the first occurrence of that pattern
> (<ind:instance datatype="int">1</ind:instance>), which ensures that even
> when there are more instances, only one (the first) would be compared
> (which is what openssh-server seems to be doing as mentioned above).
> 
> Thank you && Regards, Jan.
> --
> Jan iankko Lieskovsky / Red Hat Security Technologies Team
> 
> > 
> > 
> > Thanks,
> > Leland
> > --
> > Leland Steinke, Security+
> > DISA FSO Technical Support Contractor
> > tapestry technologies, Inc
> > 717-267-5797 (DSN 570)
> > [email protected] (gov't)
> > [email protected] (com'l)
> > 
> > 
> > > -----Original Message-----
> > > From: [email protected] [mailto:scap-
> > > [email protected]] On Behalf Of Jan
> > > Lieskovsky
> > > Sent: Thursday, November 21, 2013 11:27 AM
> > > To: [email protected]
> > > Subject: [PATCH] [RHEL6] Fix OVAL check for '3.4.3.g. Disable SSH Root
> > > Login' rule
> > > 
> > > 
> > > Fix / invert the logic of OVAL rule for '3.4.3.g. Disable SSH Root
> > > Login'
> > > XCCDF rule.
> > > 
> > > On default RHEL-6 system there's no uncommented 'PermitRootLogin yes'
> > > present in /etc/ssh/sshd_config configuration file (from the header of
> > > the
> > > config:
> > > 
> > > # The strategy used for options in the default sshd_config shipped with
> > > # OpenSSH is to specify options with their default value where
> > > # possible, but leave them commented. Uncommented options change a
> > > # default value.
> > > 
> > > From sshd_config(5):
> > > 
> > >      PermitRootLogin
> > >              Specifies whether root can log in using ssh(1).
> > >              The argument must be “yes”, “without-password”, “forced-
> > > commands-only”, or “no”.
> > >              The default is “yes”.
> > > 
> > > Therefore the default RHEL-6's sshd config is missing explicit
> > > PermitRootLogin
> > > yes, but defaulting to it. Former implementation (incorrectly) returned
> > > 'pass'
> > > as result of the scan, even when root login via SSH was allowed (can be
> > > tested on former implementation via SSH root attempt).
> > > 
> > > The proposal modifies the implementation the scan check to succeed only
> > > in
> > > case there's explicit 'PermitRootLogin no' in /etc/ssh/sshd_config, and
> > > allows possible comments behinds that definition (since it's valid
> > > config
> > > form too).
> > > 
> > > Please review.
> > > 
> > > Thank you && Regards, Jan.
> > > --
> > > Jan iankko Lieskovsky / Red Hat Security Technologies Team
> > 
> > _______________________________________________
> > scap-security-guide mailing list
> > [email protected]
> > https://lists.fedorahosted.org/mailman/listinfo/scap-security-guide
> > 
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