Red Hat Bugzilla – Bug 123849
openldap can't connect to OID- Oracle Internet Directory using ldaps
Last modified: 2015-01-07 19:07:54 EST
Description of problem:
It is not possible to connect to the Oracle Internet Directory
(version 9.0.4) with OpenLDAP using LDAPs.
The problem is related to an security fix introduced in OpenSSL
version 0.9.6d. (see: Implement a countermeasure against a
vulnerability recently found in CBC ciphersuites in SSL 3.0/TLS 1.0
by Bodo Moeller in the openssl changelog).
This fix seems not to be compliant with the SSL implementation
used by Oracle.
Solution would be to set the SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS
option within the SSL_CTX of the libldap code. (see the attached
This patch on the other side may cause security problems :-(.
Version-Release number of selected component (if applicable):
Fedora Core 1:
Steps to Reproduce:
1. setup a custom configset for Oracle Internet Directory using
SSL Server Authentication
2. create $HOME/ldaprc with:
3. try to perform the following ldapsearch command:
ldapsearch -D "cn=orcladmin,cn=Users,dc=fm-berger,dc=de" -w password
-H ldaps://fm-berger.de:4055/ -d 7 -b "cn=Users,dc=fm-berger,dc=de" -x
see the attached output of this command.
1. initial SSL handshake works
2. ldap-bind request is send
3. connection is terminated by OID lapsearch output:
TLS trace: SSL3 alert read:fatal:close notify
ldap_read: want=8, got=0
ldap_bind: Can't contact LDAP server (-1)
successful ldaps connection with result.
This issue is also filed to Oracle Metalink under the TAR-ID:
3788414.996 (EL 5/20 MORE INFORMATION FOR OID/SSL / TLS SUPPORTED?)
Created attachment 100402 [details]
debug output of the ldapsearch command used to show the problem
Created attachment 100403 [details]
quick&dirty fix for the problem setting SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS
Warning! This patch may cause security problems when applied!
This bug is filed against RHEL 3, which is in maintenance phase.
During the maintenance phase, only security errata and select mission
critical bug fixes will be released for enterprise products. Since
this bug does not meet that criteria, it is now being closed.
For more information of the RHEL errata support policy, please visit:
If you feel this bug is indeed mission critical, please contact your
support representative. You may be asked to provide detailed
information on how this bug is affecting you.