Mike Stevens wrote: > Good day. > > > > I’m an LDAP novice and am attempting to modify an LDAP client to accommodate > an LDAP server environment that makes use of referrals. > > > > I have installed openLDAP 2.4.44 on 2 RHEL 7.9 servers. > > > The initial entries in the tree on serverA contains : > > > # xxx.com <http://xxx.com> > dn: dc=xxx,dc=com > description: xxx.com <http://xxx.com> > dc: xxx > o: xxx.com <http://xxx.com> > objectClass: top > objectClass: dcObject > objectClass: organization > > # Users, xxx.com <http://xxx.com> > dn: ou=Users,dc=xxx,dc=com > ou: Users > description: xxx Users > objectClass: organizationalUnit > > # search reference > *ref: ldap://serverB.xxx.com:389/dc=uk,dc=xxx,dc=com??sub > <http://serverB.xxx.com:389/dc=uk,dc=xxx,dc=com??sub>* > > # mike, Users, xxx.com <http://xxx.com> > dn: uid=mike,ou=Users,dc=xxx,dc=com > cn: mike > ou: Users > uid: mike > givenName: Mike > mail: m...@uk.xxx.com <mailto:m...@uk.xxx.com> > objectClass: Person > objectClass: organizationalPerson > objectClass: inetOrgPerson > > > > I believe the "ref" entry is known as a subordinate referral; > > it was created by populating the tree from an LDIF file that contained the > following: > > > dn: dc=uk,dc=xxx,dc=com > objectClass: referral > objectClass: extensibleObject > dc: uk > ref: ldap://serverB.xxx.com:389/dc=uk,dc=xxx,dc=com > <http://serverB.xxx.com:389/dc=uk,dc=xxx,dc=com> > > > The intent is to redirect any requests received by serverA that refer to the > subtree uk.xxx.com <http://uk.xxx.com> to serverB. > > > The tree on serverB contains: > > > # xxx.com <http://xxx.com> > dn: dc=xxx,dc=com > description: xxx.com <http://xxx.com> > dc: xxx > o: xxx.com <http://xxx.com> > objectClass: top > objectClass: dcObject > objectClass: organization > > # uk.xxx.com <http://uk.xxx.com> > dn: dc=uk,dc=xxx,dc=com > dc: uk > o: uk.xxx.com <http://uk.xxx.com> > description: xxx Users in the UK > objectClass: dcObject > objectClass: organization > > # mike, uk.xxx.com <http://uk.xxx.com> > dn: uid=mike,dc=uk,dc=xxx,dc=com > cn: mike > uid: mike > givenName: Mike > mail: m...@uk.xxx.com <mailto:m...@uk.xxx.com> > objectClass: person > objectClass: organizationalPerson > objectClass: inetOrgPerson > > > Now, if I perform a search on serverA specifying a base of uk.xxx.com > <http://uk.xxx.com>, I get an RC=10 Referral result as expected: > > [root@serverA ~]# ldapsearch -x '(uid=mike)' -b dc=uk,dc=xxx,dc=com -LL > version: 1 > > Referral (10) > Matched DN: dc=uk,dc=xxx,dc=com > Referral: ldap://serverB.xxx.com:389/dc=uk,dc=xxx,dc=com??sub > <http://serverB.xxx.com:389/dc=uk,dc=xxx,dc=com??sub> > > ... and I can chase that referral using the -C option to retrieve the entry > from serverB: > > [root@Mike21 ~]# ldapsearch -x '(uid=mike)' -b dc=uk,dc=ibm,dc=com -LL -C > version: 1 > > dn: uid=mike,dc=uk,dc=xxx,dc=com > cn: mike > uid: mike > givenName: Mike > mail: m...@uk.xxx.com <mailto:m...@uk.xxx.com> > objectClass: person > objectClass: organizationalPerson > objectClass: inetOrgPerson > > But, if I attempt a bind to serverA using the user that exists in serverB, I > get an authentication failure: > > [root@serverA ~]# ldapsearch -x -b 'dc=uk,dc=xxx,dc=com' -D > uid=mike,dc=uk,dc=xxx,dc=com -w passw0rD > ldap_bind: Invalid credentials (49) > > Now, I realise that the failure would be expected as the bind DN doesn't > exist at serverA. > But I read that every request apart from unbind and abandon can result in a > referral. > So why doesn't the bind follow the "ref" to serverB? > Is that possible and have I not configured my server correctly?
No. See RFC3296 section 5.6.1. > > Ultimately, what I'd like to do in my client is something like: > > ld_user = ldap_init( "ldap://serverA:389/dc=uk,dc=xxx,dc=com"; , 0 ); > > ... followed by : > > err = ldap_simple_bind_s( ld_user, "uid=mike,dc=uk,dc=xxx,dc=com" , > password); > > ... and have LDAP authenticate the given user against serverB based on the > referral in serverA. > > Is this sort of set up possible? You will need to configure chaining or some other proxy mechanism instead. > > Many thanks for your advice, > Mike > -- -- Howard Chu CTO, Symas Corp. http://www.symas.com Director, Highland Sun http://highlandsun.com/hyc/ Chief Architect, OpenLDAP http://www.openldap.org/project/
