.. raw:: pdf PageBreak tl-ldap-certalias ================= Synopsis -------- **tl-ldap-certalias** [*options*] Description ----------- The :program:`tl-ldap-certalias` command can automatically update the local databases needed for smart card public key authentication, provided the system uses the OpenSSH server (or any SSH server that uses a compatible format and location for authorized public keys) and standards compliant LDAP servers where users and certificates are stored. The :program:`tl-ldap-certalias` command can also perform validation of certificates it finds in LDAP databases. Read more about this in :ref:`certalias_validation`. - On invocation, a list of all users and matching certificates is gathered. How is determined by the |certificate_user_match| configuration variable. If |allow_invalid_certificates| is no, only matching valid certificates will be gathered. .. |certificate_user_match| replace:: :servconf:`certificate_user_match ` .. |allow_invalid_certificates| replace:: :servconf:`allow_invalid_certificates ` - The user's home directory, as well as the :file:`~/.ssh` directory, are created if they are required and do not already exist. :program:`tl-ldap-certalias` reuses the :servconf:`/vsmagent/make_homedir_mode` configuration variable from vsmagent for determining the default permissions of newly created home directories. - Any old public keys added by :program:`tl-ldap-certalias` are removed from the :file:`~/.ssh/authorized_keys` file and the keys from the current set of certificates are added. - The file :file:`/etc/passwdaliases` is updated with a list of subject names and user id:s, to allow for login without usernames. See :ref:`smartcard_auto` for more information. .. note:: It should be noted that any custom entries in :file:`~/.ssh/authorized_keys` will be retained, but custom changes to :file:`/etc/passwdaliases` will be overwritten each time :program:`tl-ldap-certalias` is run. After deployment, :program:`tl-ldap-certalias` is meant to be run from cron at regular intervals, for example every 15 minutes. This makes sure that the ThinLinc system automatically keeps all user certificates updated. However, please note that if you're using certificate validation, downloading and parsing certificate revocation lists may take a long time (up to 5 minutes each). This is mitigated by caching the data from the CRL:s, but the first run, and whenever the CRL needs to be updated, may take a long time. Thus, if you have certificates from a lot of different certificate authorities, don't run :program:`tl-ldap-certalias` too often. Since the default use of this tool is to be run from cron, the default behaviour is to produces no output other than error messages. If you want more output from :program:`tl-ldap-certalias`, see the options section. .. note:: The root user must able to write to the users' home directories for :program:`tl-ldap-certalias` to be able to update the :file:`~/.ssh/authorized_keys` files. .. _certalias_config: Configuration ^^^^^^^^^^^^^ :program:`tl-ldap-certalias` uses the :servconf:`/utils/tl-ldap-certalias` hiveconf folder for configuration purposes. On a standard ThinLinc installation, it's located in :file:`/opt/thinlinc/etc/conf.d/tl-ldap-certalias.hconf`. See :ref:`configuration_tl_ldap_certalias` for details about the available parameters. .. _certalias_validation: Certificate validation ^^^^^^^^^^^^^^^^^^^^^^ :program:`tl-ldap-certalias` can perform validation of certificates found in LDAP databases by the following methods if |allow_invalid_certificates| is set to ``no``: Certificate validity and expiry dates :program:`tl-ldap-certalias` now checks the certificate validity and expiry dates and rejects certificates that are not valid yet or have expired. Matching certificate to certificate issuers Place the CA certificates you wish to trust certificates from in :file:`/opt/thinlinc/etc/ca/`. The CA certificates must be in DER form. If :program:`tl-ldap-certalias` finds a certificate with an issuer that does not match any of the certificates in :file:`/opt/thinlinc/etc/ca/`, the certificate will be considered invalid and ignored. Certificate revocation lists :program:`tl-ldap-certalias` searches the certificates it encounter for certificate revocation lists (CRL) to make sure that the certificate has not been revoked by its issuer. Once downloaded, the CRL will be cached until the time for the next scheduled update found in the CRL list has passed. .. note:: :program:`tl-ldap-certalias` can only handle CRL lists distributed with HTTP. Validation of certificate signatures. :program:`tl-ldap-certalias` can verify that the certificate signature is valid and thus assures that the certificate has not been tampered with. Options ------- .. option:: -h, --help Prints a short help text and exits. .. option:: -v, --verbose Turn on program status output to standard output. This is off by default. .. option:: -d, --debug Turn on extra debugging putput to standard output. This is off by default. .. option:: -s, --simulate Dry run mode. Specifying this option tells :program:`tl-ldap-certalias` to avoid writing any changes to disk. This is off by default.