Hi,
I have a meta DB pointing to an Active Directory backend. This is used by SASL
for authentication.
The meta DB does not contain a schema definition for the AD.
I've configured SASL to lookup sAMAccountName in AD, but this always fails
until a lookup against the meta DB has first been performed against an
attribute that the meta DB does understand (e.g. cn). Once that's been done,
the system is rock solid and can be searched on any attribute.
Looking at the debug output it seems that any initial search does not honour
the specified filter unless the attribute being searched for is defined in the
schema, but after one successful search, the LDAP server is happy to search for
these attributes.
I can work around this by doing a dummy search when the LDAP server starts, but
I'd like to understand the cause of the problem properly.
Any suggestions as to the cause of this? I'm using 2.4.20 on SLES 11.
Here's how to reproduce the problem. Meta LDAP server is listening on a socket
/var/run/slapd/slapd (configuration at end), providing dc=meta. AD is
dc=ad,dc=org,dc=uk.
After startup:
ldapsearch -H ldapi://%2Fvar%2Frun%2Fslapd%2Fldapi-meta -x -D
"cn=administrator,dc=meta" -b dc=meta -w secret sAMAccountName=user1
<nothing returned>
Try again with cn:
ldapsearch -H ldapi://%2Fvar%2Frun%2Fslapd%2Fldapi-meta -x -D
"cn=administrator,dc=meta" -b dc=meta -w secret cn=user1
<AD record returned successfully>
After this, the original search on sAMAccountName or any other attribute will
also be successful.
Debug output from slapd shows an incorrect filter on objectClass with the
original failed search:
==> rewrite_context_apply [depth=1] string='ou=ad.org.uk,dc=meta'
==> rewrite_rule_apply rule='((.+),)?ou=ad.org.uk,[ ]?dc=meta$'
string='ou=ad.org.uk,dc=meta' [1 pass(es)]
==> rewrite_context_apply [depth=1] res={0,'dc=ad,dc=org,dc=uk'}
==> rewrite_context_apply [depth=1] string='(!(objectClass=*))'
==> rewrite_context_apply [depth=1] res={0,'NULL'}
ldap_search_ext
put_filter: "(!(objectClass=*))"
put_filter: NOT
put_filter_list "(objectClass=*)"
put_filter: "(objectClass=*)"
put_filter: simple
put_simple_filter: "objectClass=*"
ldap_send_initial_request
ldap_send_server_request
A successful search with cn shows the following:
==> rewrite_context_apply [depth=1] string='ou=ad.org.uk,dc=meta'
==> rewrite_rule_apply rule='((.+),)?ou=ad.org.uk,[ ]?dc=meta$'
string='ou=ad.org.uk,dc=meta' [1 pass(es)]
==> rewrite_context_apply [depth=1] res={0,'dc=ad,dc=org,dc=uk'}
==> rewrite_context_apply [depth=1] string='(cn=user1)'
==> rewrite_context_apply [depth=1] res={0,'NULL'}
ldap_search_ext
put_filter: "(cn=user1)"
put_filter: simple
put_simple_filter: "cn=user1"
ldap_send_initial_request
ldap_send_server_request
Here's the minimal slapd.conf file:
include /etc/openldap/schema/core.schema
modulepath /usr/lib/openldap/modules
moduleload back_meta.so
argsfile /var/run/slapd/slapd.args
pidfile /var/run/slapd/slapd.pid
#################################################################
#
# Meta DB config
#
# dc=meta
#
#################################################################
database meta
suffix dc=meta
rootdn cn=administrator,dc=meta
rootpw secret
uri ldap://ad.org.uk:3268/ou=ad.org.uk,dc=meta
suffixmassage "ou=ad.org.uk,dc=meta" "dc=ad,dc=org,dc=uk"
lastmod off
idassert-bind bindmethod=simple
binddn="cn=adldap,dc=ad,dc=org,dc=uk
credentials="password"
flags=non-prescriptive
idassert-authzFrom "dn.exact:cn=administrator,dc=meta"
Thanks for any help offered.
--
Liam Gretton [email protected]
HPC Architect http://www.le.ac.uk/its
IT Services Tel: +44 (0)116 2522254
University of Leicester, University Road
Leicestershire LE1 7RH, United Kingdom
