(ITS#8037) Modifying structural OC w/relax fails on delta-syncrepl consumers

[ian@uns.ac.rs]

Full_Name: Ivan Nejgebauer
Version: 2.4.41 Engineering
OS: Linux
URL: ftp://ftp.openldap.org/incoming/ivannejgebauer-150128.tgz
Submission from: (NULL) (2001:4170:2000:2:11e5:197a:fff8:8042)


If an ldapmodify which changes an entry's structural object class using the
Relax Rules control is successfully performed on the provider in a
provider/consumer pair running delta-syncrepl, the modification will fail on the
consumer because relax is not in effect when the consumer attempts to modify its
copy of the entry.

The attached archive, which should be extracted in the root of the OpenLDAP
source tree, contains scripts and data to replicate the issue. Steps to
reproduce:

$ sh relax-syncrel-test/conf-ldap-mdb && make depend && make
$ cd relax-syncrepl-test
$ make clean-all master replica
$ ./start-master.sh
$ ./mod-l-master.sh here           # modifies an entry to prime accesslog
$ ./start-replica.sh               # writes SYNC debugging to replica.log
$ ./mod-relax-master.sh            # ldapmodify w/relax
$ tail replica.log                 # "entry failed schema check: ..."
$ ./stop-replica.sh
$ ./stop-master.sh

A trivial but indiscriminate fix is to activate Relax Rules for every modify op
on the consumer:

--- servers/slapd/syncrepl.c.orig       2015-01-22 03:02:09.000000000 +0100
+++ servers/slapd/syncrepl.c    2015-01-28 10:31:22.225060880 +0100
@@ -2349,6 +2349,7 @@
                                oes.oe_si = si;
                                LDAP_SLIST_INSERT_HEAD( &op->o_extra,
&oes.oe, oe_next );
                        }
+                       op->o_relax = SLAP_CONTROL_CRITICAL;
                        rc = op->o_bd->be_modify( op, &rs );
                        if ( SLAP_MULTIMASTER( op->o_bd )) {
                                LDAP_SLIST_REMOVE( &op->o_extra,
&oes.oe, OpExtra, oe_next );

A real fix would involve modifying the persistent search to include reqControls
in its attribute list and activating Relax Rules on the consumer only if it had
been active on the provider when the modification occurred.