[Freeipa-devel] [PATCH 0069] Adds 389DS plugin to enforce UUID token IDs

Simo Sorce simo at redhat.com
Mon Sep 22 14:55:44 UTC 2014


On Mon, 22 Sep 2014 10:02:01 -0400
Nathaniel McCallum <npmccallum at redhat.com> wrote:

> On Mon, 2014-09-22 at 09:50 -0400, Simo Sorce wrote:
> > On Mon, 22 Sep 2014 10:34:54 +0200
> > Martin Kosek <mkosek at redhat.com> wrote:
> > 
> > > On 09/22/2014 09:33 AM, thierry bordaz wrote:
> > > > Hello Nathaniel,
> > > > 
> > > >    Just a remark, in is_token if the entry is
> > > > objectclass=ipaToken it returns without freeing the
> > > > 'objectclass' char array.
> > > > 
> > > >    thanks
> > > >    thierry
> > > > 
> > > > On 09/21/2014 09:07 PM, Nathaniel McCallum wrote:
> > > >> Users that can rename the token (such as admins) can also
> > > >> create non-UUID token names.
> > > >>
> > > >> https://fedorahosted.org/freeipa/ticket/4456
> > > >>
> > > >> NOTE: this patch is an alternate approach to my patch 0065.
> > > >> This version has two main advantages compared to 0065:
> > > >> 1. Permissions are more flexible (not tied to the admin group).
> > > >> 2. Enforcement occurs at the DS-level
> > > >>
> > > >> It should also be noted that this patch does not enforce UUID
> > > >> randomness, only syntax. Users can still specify a token ID so
> > > >> long as it is in UUID format.
> > > >>
> > > >> Nathaniel
> > > 
> > > I am still thinking we may be overcomplicating it. Why cannot we
> > > use the similar UUID generation mechanism as we do for SUDO
> > > commands for example:
> > > 
> > > # ipa sudocmd-add barbar --all --raw
> > > ---------------------------
> > > Added Sudo Command "barbar"
> > > ---------------------------
> > >   dn:
> > > ipaUniqueID=3a96de14-4232-11e4-9d66-001a4a104ec9,cn=sudocmds,cn=sudo,dc=mkosek-fedora20,dc=test
> > >   sudocmd: barbar
> > >   ipaUniqueID: 3a96de14-4232-11e4-9d66-001a4a104ec9
> > >   objectClass: ipasudocmd
> > >   objectClass: ipaobject
> > > 
> > > It lets DS generate&rename the object's DN when it finds out that
> > > the ipaUniqueID is set to "autogenerate" (in baseldap.py). We
> > > could let DS generate the UUID and only add the "autogenerate"
> > > keyword in otptoken-add command.
> > > 
> > > For authorization, we can simply allow users to only add tokens
> > > with "autogenerate" ID, see my example here:
> > > 
> > > http://www.redhat.com/archives/freeipa-devel/2014-September/msg00438.html
> > > 
> > > Admin's or special privilege-owners would have more generous ACI
> > > allowing other values than just "autogenerate".
> > > 
> > > IMO, then the whole ipatoken-add mechanism would be a lot simpler
> > > and we would not need a special DS plugin (unless we want regular
> > > users to generate their own UUIDs instead of letting IPA DS to
> > > generate it
> > > - which I do not think is the case).
> > 
> > Good point Martin.
> 
> This is the avenue I first pursued. The problem is that the client has
> no way to look up the DN after the entry is added. In the case of
> sudocmd-add, the lookup is performed using the sudocmd attribute (see
> sudocmd.get_dn()). We have no similar attribute in this case and the
> lookup cannot be performed.

Well in theory we could search with creatorName and createTimestamp set
to the user's own DN and a range a few seconds in the past ...
It is not robust if you add multiple tokens at the same time, but would
this be a concern for user created tokens ?

Simo.



-- 
Simo Sorce * Red Hat, Inc * New York




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