[SSSD] [PATCHES] Support for multiple LDAP search bases

Jan Zelený jzeleny at redhat.com
Thu Oct 13 09:43:36 UTC 2011


> On Tue, 2011-10-04 at 08:04 -0400, Stephen Gallagher wrote:
> > On Tue, 2011-10-04 at 12:55 +0200, Jan Zelený wrote:
> > > > On Mon, 2011-10-03 at 14:51 -0400, Stephen Gallagher wrote:
> > > > > These patches add support for multiple search bases for users and
> > > > > groups in both direct-lookup and enumeration modes.
> > > > > 
> > > > > Addresses https://fedorahosted.org/sssd/ticket/868
> > > > > 
> > > > > Some notes: There is no patch adding multiple search base support
> > > > > for group lookups in RFC2307bis because it's meaningless right
> > > > > now. Since the group memberships are direct DNs, we do all of our
> > > > > searches as base searches, ignoring group_search_base. There is a
> > > > > separate ticket, https://fedorahosted.org/sssd/ticket/960 that
> > > > > will need to address this, taking advantage of the multiple search
> > > > > base features.
> > > > > 
> > > > > Also, while working through this, I opened
> > > > > https://fedorahosted.org/sssd/ticket/1006 as I noticed that we are
> > > > > using far too many separate transactions while processing
> > > > > RFC2307bis (which is likely the cause of the extreme slowdown that
> > > > > some of our users were reporting with AD).
> > > > > 
> > > > > These patches don't really work separately, but they've been broken
> > > > > up to make review much easier.
> > > > > 
> > > > > 
> > > > > Patch 0001: Remove some unused options in a struct
> > > > > 
> > > > > Patch 0002: Fix size return for split_on_separator()
> > > > > It was returning the size of the array, rather than the number of
> > > > > elements. (The array was NULL-terminated). This argument was only
> > > > > used in one place that was actually working around this odd return
> > > > > value.
> > > > > 
> > > > > Patch 0003: Make sdap_get_id_specific_filter() more strict
> > > > > Just makes it take const char * instead of char *.
> > > > > 
> > > > > Patch 0004: Add parser for multiple search bases
> > > > > As discussed on the list, this will the ldap_*_search_base options
> > > > > in the form of:
> > > > > search_base[?scope?[filter][?search_base?scope?[filter]]*]
> > > > > This is backwards-compatible (just use a search base)
> > > > > 
> > > > > Patch 0005: Add support for multiple search bases for users
> > > > > 
> > > > > Patch 0006: Add support for multiple search bases for netgroups
> > > > > 
> > > > > Patch 0007: Add support for multiple search bases for RFC2307
> > > > > groups
> > > > > 
> > > > > Patch 0008: Add support for multiple search bases for initgroups
> > > > > (user portion)
> > > > > 
> > > > > Patch 0009: Add support for multiple search bases for initgroups
> > > > > (RFC2307 group portion)
> > > > > 
> > > > > Patch 0010: Add support for multiple search bases for initgroups
> > > > > (RFC2307 group portion)
> > > > > This patch I'm not 100% sure of. It may need more processing. With
> > > > > RFC2307, it was safe to have duplicate groups in the list, because
> > > > > only the group name is important (and we guarantee that the name
> > > > > list has only unique values before saving it). With RFC2307bis,
> > > > > I'm not sure if it's safe to add two groups that may have the same
> > > > > name. Comments welcome.
> > > > > 
> > > > > Patch 0011: Update manpages with multiple search base information
> > > > > 
> > > > > Patch 0012: Convert ldap_*_search_filter
> > > > > Instead of making this a global option for all user lookups, make
> > > > > it only used if the search base is passed without an explicit
> > > > > filter. The idea here is to deprecate the old separate
> > > > > ldap_user_search_filter and ldap_group_search_filter options in
> > > > > favor of the new representation (which is closer to the
> > > > > traditional nss_ldap representation).
> > > > > 
> > > > > Patch 0013: Add support for multiple search bases for user
> > > > > enumeration
> > > > > 
> > > > > Patch 0014: Add support for multiple search bases for group
> > > > > enumeration This changes our behavior slightly with regard to
> > > > > handling direct lookups that return more than one entry. In the
> > > > > old code, we had a bug that would cause SSSD to treat this as an
> > > > > enumeration (instead of a direct lookup). This was a bug and has
> > > > > been fixed incidentally as part of this modification.
> > > > 
> > > > For the record, because I forgot to mention it in my first email: I
> > > > tried to reproduce the issue jzeleny saw in the earlier thread
> > > > without success. Either I inadvertently fixed it with the changes I
> > > > made or it was caused by other changes in his environment (possibly
> > > > the memberOf work).
> > > > 
> > > > I tested it with exactly the same users and groups, using SSSD
> > > > speaking to a FreeIPA server (in both rfc2307bis mode and ipa
> > > > backend).
> > > > 
> > > > 
> > > > 
> > > > His original comment:
> > > > 
> > > > So NACK after all. Following test failed:
> > > > 
> > > > I tried following membership structure. I have 3 groups: topgroup,
> > > > middlegroup
> > > > and bottomgroup and 2 users:  user1 and user2
> > > > 
> > > > The relationship is following:
> > > > topgroup -> middlegroup, user1
> > > > middlegroup -> user2, bottomgroup
> > > > bottomgroup -> user1
> > > > 
> > > > 
> > > > getent group topgroup gives me result with no members, the same test
> > > > on master
> > > > returns the expected result.
> > > 
> > > Stephen,
> > > I still see the same error I reported. This time I had time to take a
> > > look into logs and I found out that with your patches, a lookup on IPA
> > > server is performed on the entire tree whereas the lookup without your
> > > patch is performed only on cn=accounts subtree. As a result, the
> > > lookup with your patches finds two group records (one in cn=accounts
> > > and one in cn=compat) and refuses to continue. I have no ldap search
> > > base configured manually, it is taken from IPA server.
> > 
> > Yeah, this is a bug in FreeIPA. If we use autodetection in FreeIPA right
> > now, it returns the common search base for both compat and standard.
> > It's not an SSSD issue. I've opened
> > https://fedorahosted.org/freeipa/ticket/1919 upstream to deal with this.
> > In the meantime, please just set the search base appropriately (which is
> > done automatically by ipa-client-install).
> 
> Well, I have a bit of egg on my face. Jan was completely right, and I
> had forgotten to ensure that the IPA provider was picking up the correct
> search bases. I've now updated patch 0004 to correct this.

Steve,
I finally finished the review:

#1-9: ACK

#11:
- mention what other values are acceptable for scope (you have only subtree in 
the example)
- maybe mention a reference to a document about LDAP filters? Or a brief 
description how the filter can look like. This is not necessary, just a thought 
to avoid some user questions in the future.



Consider following patches ACKed, I leave suggested changes at your 
discretion:

#10:
sdap_initgr_rfc2307bis_send
- how about making one fail/done label and some gotos?
sdap_initgr_rfc2307bis_process
- I'd rather use memcpy than the cycle

#13:
sdap_get_users_process
- I'd rather use memcpy than the cycle

#14:
sdap_get_groups_process
- I'd rather use memcpy than the cycle


Thanks
Jan
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 836 bytes
Desc: This is a digitally signed message part.
URL: <https://lists.fedorahosted.org/pipermail/sssd-devel/attachments/20111013/cc29057b/attachment.sig>


More information about the sssd-devel mailing list