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    SubjectRe: LSM conversion to static interface
    Jan Engelhardt wrote:
    > On Oct 23 2007 07:44, Giacomo Catenazzi wrote:
    >>> I do have a pseudo LSM called "multiadm" at
    >>> http://freshmeat.net/p/multiadm/ , quoting:
    >>> Policy is dead simple since it is based on UIDs. The UID ranges can be
    >>> set on module load time or during runtime (sysfs params). This LSM is
    >>> basically grants extra rights unlike most other LSMs[1], which is why
    >>> modprobe makes much more sense here. (It also does not have to do any
    >>> security labelling that would require it to be loaded at boot time
    >>> already.)
    >> But his is against LSM design (and first agreements about LSM):
    >> LSM can deny rights, but it should not give extra permissions
    >> or bypass standard unix permissions.
    >
    > It is just not feasible to add ACLs to all million files in /home,
    > also because ACLs are limited to around 25 entries.
    > And it is obvious I do not want <prof> to have UID 0, because
    > then you cannot distinguish who created what file.
    > So the requirement to the task is to have unique UIDs.
    > The next logical step would be to give capabilities to those UIDs.
    >
    > *Is that wrong*? Who says that only UID 0 is allowed to have
    > all 31 capability bits turned on, and that all non-UID 0 users
    > need to have all 31 capability bits turned off?
    >
    > So, we give caps to the subadmins (which is IMHO a natural task),
    > and then, as per LSM design (wonder where that is written) deny
    > some of the rights that the capabilities raised for subadmins grant,
    > because that is obviously too much.

    Nothing wrong. I only said that it was against (IIRC) the
    principle of LSM in kernel (we should only remove capacities).
    I've nothing against the changing the design or rules.
    It was only a commentary, to be sure that we know what we do ;-)

    ciao
    cate
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