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Chapter 110. Identity Management security settings

Learn more about security-related features of Identity Management.

110.1. How Identity Management applies default security settings

By default, Identity Management (IdM) on RHEL 8 uses the system-wide crypto policy. The benefit of this policy is that you do not need to harden individual IdM components manually.

Important

Red Hat recommends that you use the system-wide crypto policy. Changing individual security settings can break components of IdM. For example, Java in RHEL 8 does not fully support the TLS 1.3 protocol. Therefore, using this protocol can cause failures in IdM.

Additional resources

  • See the crypto-policies(7) man page.

110.2. Anonymous LDAP binds in Identity Management

By default, anonymous binds to the Identity Management (IdM) LDAP server are enabled. Anonymous binds can expose certain configuration settings or directory values. However, some utilities, such as realmd, or older RHEL clients require anonymous binds enabled to discover domain settings when enrolling a client.

Additional resources

110.3. Disabling anonymous binds

You can disable anonymous binds on the Identity Management (IdM) 389 Directory Server instance by using LDAP tools to reset the nsslapd-allow-anonymous-access attribute.

These are the valid values for the nsslapd-allow-anonymous-access attribute:

  • on: allows all anonymous binds (default)
  • rootdse: allows anonymous binds only for root DSE information
  • off: disallows any anonymous binds

Red Hat does not recommend completely disallowing anonymous binds by setting the attribute to off, because this also blocks external clients from checking the server configuration. LDAP and web clients are not necessarily domain clients, so they connect anonymously to read the root DSE file to get connection information.

By changing the value of the nsslapd-allow-anonymous-access attribute to rootdse, you allow access to the root DSE and server configuration without any access to the directory data.

Warning

Certain clients rely on anonymous binds to discover IdM settings. Additionally, the compat tree can break for legacy clients that are not using authentication. Perform this procedure only if your clients do not require anonymous binds.

Prerequisites

  • You can authenticate as the Directory Manager to write to the LDAP server.
  • You can authenticate as the root user to restart IdM services.

Procedure

  1. Change the nsslapd-allow-anonymous-access attribute to rootdse. 

    $ ldapmodify -x -D "cn=Directory Manager" -W -h server.example.com -p 389
Enter LDAP Password:
dn: cn=config
changetype: modify
replace: nsslapd-allow-anonymous-access
nsslapd-allow-anonymous-access: rootdse

modifying entry "cn=config"

  2. Restart the 389 Directory Server instance to load the new setting. 

    # systemctl restart dirsrv.target

Verification

  • Display the value of the nsslapd-allow-anonymous-access attribute. 

    $ ldapsearch -x -D "cn=Directory Manager" -b cn=config -W -h server.example.com  -p 389 nsslapd-allow-anonymous-access | grep nsslapd-allow-anonymous-access
Enter LDAP Password:
# requesting: nsslapd-allow-anonymous-access
nsslapd-allow-anonymous-access: rootdse

Additional resources