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=== Another Cure: ===
As per [[http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=541256|Bug#541256]], you can also fix this problem in {{{/etc/ldap/slapd.conf}}} using something like:
{{{
TLSCipherSuite +RSA:+AES-256-CBC:+SHA1
}}}

Setting up an LDAP server with OpenLDAP

Install the OpenLDAP package slapd

Install the package with:

  # apt-get install slapd

answering the prompts as follows:

  • For the DNS domain name, enter your domain name.


    This will be translated to an LDAP DN (for example, 'example.com' would become 'dc=example, dc=com'). This becomes what is known as your BaseDN, the root of your database.

  • For your organzation you can enter any string; this becomes associated the 'ou' field of your BaseDN record.

  • Next enter your LDAP administrator password twice. This will set the password for 'cn=admin, BaseDN and give 'cn=admin, BaseDN' write access to everything in your LDAP tree.

  • Accept the default of No to the question Allow LDAPv2 protocol

For querying the LDAP server utilities like ldapsearch are available. See the LDAP/LDAPUtils topic for more details.

For better performance do more indexing than the default.

Modify /etc/ldap/slapd.conf to contain the following:

index   objectClass             eq
index   cn                      pres,sub,eq
index   sn                      pres,sub,eq
index   uid                     pres,sub,eq
index   displayName             pres,sub,eq
index   default                 sub
index   uidNumber               eq
index   gidNumber               eq
index   mail,givenName          eq,subinitial
index   dc                      eq

After any new indexes have been defined or other major database changes have been made (e.g. slapadd was used) it is best to recreate the indexes. Note that you should stop slapd before recreating the indexes and should fix the permissions afterward.

  # /etc/init.d/slapd stop
  # slapindex
  # chown -R openldap:openldap /var/lib/ldap
  # /etc/init.d/slapd start

Configuring 'chsh' and 'chfn' to work with LDAP

Edit '/etc/ldap/slapd.conf' to allow access for users to update their loginShell and gecos entries by adding the following before the 'access to *' entry:

access to attrs=loginShell,gecos
      by dn="cn=admin,dc=example,dc=com" write
      by self write
      by * read

For SAMBA LDAP support

For Samba LDAP, slapd needs the Samba schema. The Debian package seems to have a samba.schema file which is old and out of date, and a samba.schema.gz file which is actually the correct one. Do the following (as root):

  # zcat /usr/share/doc/samba-doc/examples/LDAP/samba.schema.gz > /etc/ldap/schema/samba.schema

Now add the following line to /etc/ldap/slapd.conf after the other includes:

include /etc/ldap/schema/samba.schema

And restart slapd:

  # /etc/init.d/slapd restart

Access controls for subtree-specific LDAP Admins

If you choose to use LDAP for many functions, such as having a single server for DNS, Authentication, and networking flat file database replacement, you may wish to have LDAP administrative users for each subtree in addition to the global admin (dn="cn=admin, dc=example, dc=com). The following example is useful when using a separate authentication tree which includes Samba.

 # The manager dn has full write access to the auth subtree
 # Everyone else has read access to not otherwise protected fields and entries
 access to dn.sub="ou=auth,dc=example,dc=com"
         by dn="cn=Manager,ou=auth,dc=example,dc=com" write
         by * read

Configuring LDAPS

Configuring the certificate (and possibly the CA used) in /etc/ldap/slapd.conf:

TLSCACertificateFile    /etc/ssl/certs/whaterver_ca_you_use.pem
TLSCertificateKeyFile   /etc/ssl/private/example.com.pem.pem
TLSCertificateFile      /etc/ssl/certs/example.com.pem

By default, slapd runs as user/group openldap, so it can't read the key file. On Debian Lenny, the preferred solution to this dilemma seems to be to chown the key to root:ssl-cert, set permissions to 640 and add the user openldap to group ssl-cert.

Symptoms:

In slapd debug output:

[...] TLS: could not set cipher list HIGH:MEDIUM:-SSLv2.  (or similar)

In /var/log/syslog:

[...] main: TLS init def ctx failed: -1

Diagnosis:

If you try to install the OpenLDAP server (slapd) with Debian Lenny, it comes compiled against the GnuTLS library. It means you cannot use an OpenSSL style directive like TLSCipherSuite HIGH:MEDIUM:-SSLv2 in slapd.conf.

Cure:

In /etc/ldap/slapd.conf, you use something like:

TLSCipherSuite TLS_RSA_AES_256_CBC_SHA

To get all the supported GnuTLS cipher suite names:

# aptitude install gnutls-bin
# gnutls-cli -l

Another Cure:

As per Bug#541256, you can also fix this problem in /etc/ldap/slapd.conf using something like:

TLSCipherSuite +RSA:+AES-256-CBC:+SHA1


CategorySystemAdministration