.. _kdc.conf(5):

kdc.conf

========

The kdc.conf file supplements :ref:`krb5.conf(5)` for programs which

are typically only used on a KDC, such as the :ref:`krb5kdc(8)` and

:ref:`kadmind(8)` daemons and the :ref:`kdb5_util(8)` program.

Relations documented here may also be specified in krb5.conf; for the

KDC programs mentioned, krb5.conf and kdc.conf will be merged into a

single configuration profile.

Normally, the kdc.conf file is found in the KDC state directory,

|kdcdir|.  You can override the default location by setting the

environment variable **KRB5_KDC_PROFILE**.

Please note that you need to restart the KDC daemon for any configuration

changes to take effect.

Structure

---------

The kdc.conf file is set up in the same format as the

:ref:`krb5.conf(5)` file.

Sections

--------

The kdc.conf file may contain the following sections:

==================== =================================================

:ref:`kdcdefaults`   Default values for KDC behavior

:ref:`kdc_realms`    Realm-specific database configuration and settings

:ref:`dbdefaults`    Default database settings

:ref:`dbmodules`     Per-database settings

:ref:`logging`       Controls how Kerberos daemons perform logging

==================== =================================================

.. _kdcdefaults:

[kdcdefaults]

~~~~~~~~~~~~~

Some relations in the [kdcdefaults] section specify default values for

realm variables, to be used if the [realms] subsection does not

contain a relation for the tag.  See the :ref:`kdc_realms` section for

the definitions of these relations.

* **host_based_services**

* **kdc_listen**

* **kdc_ports**

* **kdc_tcp_listen**

* **kdc_tcp_ports**

* **no_host_referral**

* **restrict_anonymous_to_tgt**

The following [kdcdefaults] variables have no per-realm equivalent:

**kdc_max_dgram_reply_size**

    Specifies the maximum packet size that can be sent over UDP.  The

    default value is 4096 bytes.

**kdc_tcp_listen_backlog**

    (Integer.)  Set the size of the listen queue length for the KDC

    daemon.  The value may be limited by OS settings.  The default

    value is 5.

**spake_preauth_kdc_challenge**

    (String.)  Specifies the group for a SPAKE optimistic challenge.

    See the **spake_preauth_groups** variable in :ref:`libdefaults`

    for possible values.  The default is not to issue an optimistic

    challenge.  (New in release 1.17.)

.. _kdc_realms:

[realms]

~~~~~~~~

Each tag in the [realms] section is the name of a Kerberos realm.  The

value of the tag is a subsection where the relations define KDC

parameters for that particular realm.  The following example shows how

to define one parameter for the ATHENA.MIT.EDU realm::

    [realms]

        ATHENA.MIT.EDU = {

            max_renewable_life = 7d 0h 0m 0s

        }

The following tags may be specified in a [realms] subsection:

**acl_file**

    (String.)  Location of the access control list file that

    :ref:`kadmind(8)` uses to determine which principals are allowed

    which permissions on the Kerberos database.  To operate without an

    ACL file, set this relation to the empty string with ``acl_file =

    ""``.  The default value is |kdcdir|\ ``/kadm5.acl``.  For more

    information on Kerberos ACL file see :ref:`kadm5.acl(5)`.

**database_module**

    (String.)  This relation indicates the name of the configuration

    section under :ref:`dbmodules` for database-specific parameters

    used by the loadable database library.  The default value is the

    realm name.  If this configuration section does not exist, default

    values will be used for all database parameters.

**database_name**

    (String, deprecated.)  This relation specifies the location of the

    Kerberos database for this realm, if the DB2 module is being used

    and the :ref:`dbmodules` configuration section does not specify a

    database name.  The default value is |kdcdir|\ ``/principal``.

**default_principal_expiration**

    (:ref:`abstime` string.)  Specifies the default expiration date of

    principals created in this realm.  The default value is 0, which

    means no expiration date.

**default_principal_flags**

    (Flag string.)  Specifies the default attributes of principals

    created in this realm.  The format for this string is a

    comma-separated list of flags, with '+' before each flag that

    should be enabled and '-' before each flag that should be

    disabled.  The **postdateable**, **forwardable**, **tgt-based**,

    **renewable**, **proxiable**, **dup-skey**, **allow-tickets**, and

    **service** flags default to enabled.

    There are a number of possible flags:

    **allow-tickets**

        Enabling this flag means that the KDC will issue tickets for

        this principal.  Disabling this flag essentially deactivates

        the principal within this realm.

    **dup-skey**

        Enabling this flag allows the KDC to issue user-to-user

        service tickets for this principal.

    **forwardable**

        Enabling this flag allows the principal to obtain forwardable

        tickets.

    **hwauth**

        If this flag is enabled, then the principal is required to

        preauthenticate using a hardware device before receiving any

        tickets.

    **no-auth-data-required**

        Enabling this flag prevents PAC or AD-SIGNEDPATH data from

        being added to service tickets for the principal.

    **ok-as-delegate**

        If this flag is enabled, it hints the client that credentials

        can and should be delegated when authenticating to the

        service.

    **ok-to-auth-as-delegate**

        Enabling this flag allows the principal to use S4USelf tickets.

    **postdateable**

        Enabling this flag allows the principal to obtain postdateable

        tickets.

    **preauth**

        If this flag is enabled on a client principal, then that

        principal is required to preauthenticate to the KDC before

        receiving any tickets.  On a service principal, enabling this

        flag means that service tickets for this principal will only

        be issued to clients with a TGT that has the preauthenticated

        bit set.

    **proxiable**

        Enabling this flag allows the principal to obtain proxy

        tickets.

    **pwchange**

        Enabling this flag forces a password change for this

        principal.

    **pwservice**

        If this flag is enabled, it marks this principal as a password

        change service.  This should only be used in special cases,

        for example, if a user's password has expired, then the user

        has to get tickets for that principal without going through

        the normal password authentication in order to be able to

        change the password.

    **renewable**

        Enabling this flag allows the principal to obtain renewable

        tickets.

    **service**

        Enabling this flag allows the the KDC to issue service tickets

        for this principal.  In release 1.17 and later, user-to-user

        service tickets are still allowed if the **dup-skey** flag is

        set.

    **tgt-based**

        Enabling this flag allows a principal to obtain tickets based

        on a ticket-granting-ticket, rather than repeating the

        authentication process that was used to obtain the TGT.

**dict_file**

    (String.)  Location of the dictionary file containing strings that

    are not allowed as passwords.  The file should contain one string

    per line, with no additional whitespace.  If none is specified or

    if there is no policy assigned to the principal, no dictionary

    checks of passwords will be performed.

**encrypted_challenge_indicator**

    (String.)  Specifies the authentication indicator value that the KDC

    asserts into tickets obtained using FAST encrypted challenge

    pre-authentication.  New in 1.16.

**host_based_services**

    (Whitespace- or comma-separated list.)  Lists services which will

    get host-based referral processing even if the server principal is

    not marked as host-based by the client.

**iprop_enable**

    (Boolean value.)  Specifies whether incremental database

    propagation is enabled.  The default value is false.

**iprop_master_ulogsize**

    (Integer.)  Specifies the maximum number of log entries to be

    retained for incremental propagation.  The default value is 1000.

    Prior to release 1.11, the maximum value was 2500.

**iprop_replica_poll**

    (Delta time string.)  Specifies how often the replica KDC polls

    for new updates from the master.  The default value is ``2m``

    (that is, two minutes).  New in release 1.17.

**iprop_slave_poll**

    (Delta time string.)  The name for **iprop_replica_poll** prior to

    release 1.17.  Its value is used as a fallback if

    **iprop_replica_poll** is not specified.

**iprop_listen**

    (Whitespace- or comma-separated list.)  Specifies the iprop RPC

    listening addresses and/or ports for the :ref:`kadmind(8)` daemon.

    Each entry may be an interface address, a port number, or an

    address and port number separated by a colon.  If the address

    contains colons, enclose it in square brackets.  If no address is

    specified, the wildcard address is used.  If kadmind fails to bind

    to any of the specified addresses, it will fail to start.  The

    default (when **iprop_enable** is true) is to bind to the wildcard

    address at the port specified in **iprop_port**.  New in release

    1.15.

**iprop_port**

    (Port number.)  Specifies the port number to be used for

    incremental propagation.  When **iprop_enable** is true, this

    relation is required in the replica KDC configuration file, and

    this relation or **iprop_listen** is required in the master

    configuration file, as there is no default port number.  Port

    numbers specified in **iprop_listen** entries will override this

    port number for the :ref:`kadmind(8)` daemon.

**iprop_resync_timeout**

    (Delta time string.)  Specifies the amount of time to wait for a

    full propagation to complete.  This is optional in configuration

    files, and is used by replica KDCs only.  The default value is 5

    minutes (``5m``).  New in release 1.11.

**iprop_logfile**

    (File name.)  Specifies where the update log file for the realm

    database is to be stored.  The default is to use the

    **database_name** entry from the realms section of the krb5 config

    file, with ``.ulog`` appended.  (NOTE: If **database_name** isn't

    specified in the realms section, perhaps because the LDAP database

    back end is being used, or the file name is specified in the

    [dbmodules] section, then the hard-coded default for

    **database_name** is used.  Determination of the **iprop_logfile**

    default value will not use values from the [dbmodules] section.)

**kadmind_listen**

    (Whitespace- or comma-separated list.)  Specifies the kadmin RPC

    listening addresses and/or ports for the :ref:`kadmind(8)` daemon.

    Each entry may be an interface address, a port number, or an

    address and port number separated by a colon.  If the address

    contains colons, enclose it in square brackets.  If no address is

    specified, the wildcard address is used.  If kadmind fails to bind

    to any of the specified addresses, it will fail to start.  The

    default is to bind to the wildcard address at the port specified

    in **kadmind_port**, or the standard kadmin port (749).  New in

    release 1.15.

**kadmind_port**

    (Port number.)  Specifies the port on which the :ref:`kadmind(8)`

    daemon is to listen for this realm.  Port numbers specified in

    **kadmind_listen** entries will override this port number.  The

    assigned port for kadmind is 749, which is used by default.

**key_stash_file**

    (String.)  Specifies the location where the master key has been

    stored (via kdb5_util stash).  The default is |kdcdir|\

    ``/.k5.REALM``, where *REALM* is the Kerberos realm.

**kdc_listen**

    (Whitespace- or comma-separated list.)  Specifies the UDP

    listening addresses and/or ports for the :ref:`krb5kdc(8)` daemon.

    Each entry may be an interface address, a port number, or an

    address and port number separated by a colon.  If the address

    contains colons, enclose it in square brackets.  If no address is

    specified, the wildcard address is used.  If no port is specified,

    the standard port (88) is used.  If the KDC daemon fails to bind

    to any of the specified addresses, it will fail to start.  The

    default is to bind to the wildcard address on the standard port.

    New in release 1.15.

**kdc_ports**

    (Whitespace- or comma-separated list, deprecated.)  Prior to

    release 1.15, this relation lists the ports for the

    :ref:`krb5kdc(8)` daemon to listen on for UDP requests.  In

    release 1.15 and later, it has the same meaning as **kdc_listen**

    if that relation is not defined.

**kdc_tcp_listen**

    (Whitespace- or comma-separated list.)  Specifies the TCP

    listening addresses and/or ports for the :ref:`krb5kdc(8)` daemon.

    Each entry may be an interface address, a port number, or an

    address and port number separated by a colon.  If the address

    contains colons, enclose it in square brackets.  If no address is

    specified, the wildcard address is used.  If no port is specified,

    the standard port (88) is used.  To disable listening on TCP, set

    this relation to the empty string with ``kdc_tcp_listen = ""``.

    If the KDC daemon fails to bind to any of the specified addresses,

    it will fail to start.  The default is to bind to the wildcard

    address on the standard port.  New in release 1.15.

**kdc_tcp_ports**

    (Whitespace- or comma-separated list, deprecated.)  Prior to

    release 1.15, this relation lists the ports for the

    :ref:`krb5kdc(8)` daemon to listen on for UDP requests.  In

    release 1.15 and later, it has the same meaning as

    **kdc_tcp_listen** if that relation is not defined.

**kpasswd_listen**

    (Comma-separated list.)  Specifies the kpasswd listening addresses

    and/or ports for the :ref:`kadmind(8)` daemon.  Each entry may be

    an interface address, a port number, or an address and port number

    separated by a colon.  If the address contains colons, enclose it

    in square brackets.  If no address is specified, the wildcard

    address is used.  If kadmind fails to bind to any of the specified

    addresses, it will fail to start.  The default is to bind to the

    wildcard address at the port specified in **kpasswd_port**, or the

    standard kpasswd port (464).  New in release 1.15.

**kpasswd_port**

    (Port number.)  Specifies the port on which the :ref:`kadmind(8)`

    daemon is to listen for password change requests for this realm.

    Port numbers specified in **kpasswd_listen** entries will override

    this port number.  The assigned port for password change requests

    is 464, which is used by default.

**master_key_name**

    (String.)  Specifies the name of the principal associated with the

    master key.  The default is ``K/M``.

**master_key_type**

    (Key type string.)  Specifies the master key's key type.  The

    default value for this is |defmkey|.  For a list of all possible

    values, see :ref:`Encryption_types`.

**max_life**

    (:ref:`duration` string.)  Specifies the maximum time period for

    which a ticket may be valid in this realm.  The default value is

    24 hours.

**max_renewable_life**

    (:ref:`duration` string.)  Specifies the maximum time period

    during which a valid ticket may be renewed in this realm.

    The default value is 0.

**no_host_referral**

    (Whitespace- or comma-separated list.)  Lists services to block

    from getting host-based referral processing, even if the client

    marks the server principal as host-based or the service is also

    listed in **host_based_services**.  ``no_host_referral = *`` will

    disable referral processing altogether.

**reject_bad_transit**

    (Boolean value.)  If set to true, the KDC will check the list of

    transited realms for cross-realm tickets against the transit path

    computed from the realm names and the capaths section of its

    :ref:`krb5.conf(5)` file; if the path in the ticket to be issued

    contains any realms not in the computed path, the ticket will not

    be issued, and an error will be returned to the client instead.

    If this value is set to false, such tickets will be issued

    anyways, and it will be left up to the application server to

    validate the realm transit path.

    If the disable-transited-check flag is set in the incoming

    request, this check is not performed at all.  Having the

    **reject_bad_transit** option will cause such ticket requests to

    be rejected always.

    This transit path checking and config file option currently apply

    only to TGS requests.

    The default value is true.

**restrict_anonymous_to_tgt**

    (Boolean value.)  If set to true, the KDC will reject ticket

    requests from anonymous principals to service principals other

    than the realm's ticket-granting service.  This option allows

    anonymous PKINIT to be enabled for use as FAST armor tickets

    without allowing anonymous authentication to services.  The

    default value is false.  New in release 1.9.

**spake_preauth_indicator**

    (String.)  Specifies an authentication indicator value that the

    KDC asserts into tickets obtained using SPAKE pre-authentication.

    The default is not to add any indicators.  This option may be

    specified multiple times.  New in release 1.17.

**supported_enctypes**

    (List of *key*:*salt* strings.)  Specifies the default key/salt

    combinations of principals for this realm.  Any principals created

    through :ref:`kadmin(1)` will have keys of these types.  The

    default value for this tag is |defkeysalts|.  For lists of

    possible values, see :ref:`Keysalt_lists`.

.. _dbdefaults:

[dbdefaults]

~~~~~~~~~~~~

The [dbdefaults] section specifies default values for some database

parameters, to be used if the [dbmodules] subsection does not contain

a relation for the tag.  See the :ref:`dbmodules` section for the

definitions of these relations.

* **ldap_kerberos_container_dn**

* **ldap_kdc_dn**

* **ldap_kdc_sasl_authcid**

* **ldap_kdc_sasl_authzid**

* **ldap_kdc_sasl_mech**

* **ldap_kdc_sasl_realm**

* **ldap_kadmind_dn**

* **ldap_kadmind_sasl_authcid**

* **ldap_kadmind_sasl_authzid**

* **ldap_kadmind_sasl_mech**

* **ldap_kadmind_sasl_realm**

* **ldap_service_password_file**

* **ldap_conns_per_server**

.. _dbmodules:

[dbmodules]

~~~~~~~~~~~

The [dbmodules] section contains parameters used by the KDC database

library and database modules.  Each tag in the [dbmodules] section is

the name of a Kerberos realm or a section name specified by a realm's

**database_module** parameter.  The following example shows how to

define one database parameter for the ATHENA.MIT.EDU realm::

    [dbmodules]

        ATHENA.MIT.EDU = {

            disable_last_success = true

        }

The following tags may be specified in a [dbmodules] subsection:

**database_name**

    This DB2-specific tag indicates the location of the database in

    the filesystem.  The default is |kdcdir|\ ``/principal``.

**db_library**

    This tag indicates the name of the loadable database module.  The

    value should be ``db2`` for the DB2 module, ``klmdb`` for the LMDB

    module, or ``kldap`` for the LDAP module.

**disable_last_success**

    If set to ``true``, suppresses KDC updates to the "Last successful

    authentication" field of principal entries requiring

    preauthentication.  Setting this flag may improve performance.

    (Principal entries which do not require preauthentication never

    update the "Last successful authentication" field.).  First

    introduced in release 1.9.

**disable_lockout**

    If set to ``true``, suppresses KDC updates to the "Last failed

    authentication" and "Failed password attempts" fields of principal

    entries requiring preauthentication.  Setting this flag may

    improve performance, but also disables account lockout.  First

    introduced in release 1.9.

**ldap_conns_per_server**

    This LDAP-specific tag indicates the number of connections to be

    maintained per LDAP server.

**ldap_kdc_dn** and **ldap_kadmind_dn**

    These LDAP-specific tags indicate the default DN for binding to

    the LDAP server.  The :ref:`krb5kdc(8)` daemon uses

    **ldap_kdc_dn**, while the :ref:`kadmind(8)` daemon and other

    administrative programs use **ldap_kadmind_dn**.  The kadmind DN

    must have the rights to read and write the Kerberos data in the

    LDAP database.  The KDC DN must have the same rights, unless

    **disable_lockout** and **disable_last_success** are true, in

    which case it only needs to have rights to read the Kerberos data.

    These tags are ignored if a SASL mechanism is set with

    **ldap_kdc_sasl_mech** or **ldap_kadmind_sasl_mech**.

**ldap_kdc_sasl_mech** and **ldap_kadmind_sasl_mech**

    These LDAP-specific tags specify the SASL mechanism (such as

    ``EXTERNAL``) to use when binding to the LDAP server.  New in

    release 1.13.

**ldap_kdc_sasl_authcid** and **ldap_kadmind_sasl_authcid**

    These LDAP-specific tags specify the SASL authentication identity

    to use when binding to the LDAP server.  Not all SASL mechanisms

    require an authentication identity.  If the SASL mechanism

    requires a secret (such as the password for ``DIGEST-MD5``), these

    tags also determine the name within the

    **ldap_service_password_file** where the secret is stashed.  New

    in release 1.13.

**ldap_kdc_sasl_authzid** and **ldap_kadmind_sasl_authzid**

    These LDAP-specific tags specify the SASL authorization identity

    to use when binding to the LDAP server.  In most circumstances

    they do not need to be specified.  New in release 1.13.

**ldap_kdc_sasl_realm** and **ldap_kadmind_sasl_realm**

    These LDAP-specific tags specify the SASL realm to use when

    binding to the LDAP server.  In most circumstances they do not

    need to be set.  New in release 1.13.

**ldap_kerberos_container_dn**

    This LDAP-specific tag indicates the DN of the container object

    where the realm objects will be located.

**ldap_servers**

    This LDAP-specific tag indicates the list of LDAP servers that the

    Kerberos servers can connect to.  The list of LDAP servers is

    whitespace-separated.  The LDAP server is specified by a LDAP URI.

    It is recommended to use ``ldapi:`` or ``ldaps:`` URLs to connect

    to the LDAP server.

**ldap_service_password_file**

    This LDAP-specific tag indicates the file containing the stashed

    passwords (created by ``kdb5_ldap_util stashsrvpw``) for the

    **ldap_kdc_dn** and **ldap_kadmind_dn** objects, or for the

    **ldap_kdc_sasl_authcid** or **ldap_kadmind_sasl_authcid** names

    for SASL authentication.  This file must be kept secure.

**mapsize**

    This LMDB-specific tag indicates the maximum size of the two

    database environments in megabytes.  The default value is 128.

    Increase this value to address "Environment mapsize limit reached"

    errors.  New in release 1.17.

**max_readers**

    This LMDB-specific tag indicates the maximum number of concurrent

    reading processes for the databases.  The default value is 128.

    New in release 1.17.

**nosync**

    This LMDB-specific tag can be set to improve the throughput of

    kadmind and other administrative agents, at the expense of

    durability (recent database changes may not survive a power outage

    or other sudden reboot).  It does not affect the throughput of the

    KDC.  The default value is false.  New in release 1.17.

**unlockiter**

    If set to ``true``, this DB2-specific tag causes iteration

    operations to release the database lock while processing each

    principal.  Setting this flag to ``true`` can prevent extended

    blocking of KDC or kadmin operations when dumps of large databases

    are in progress.  First introduced in release 1.13.

The following tag may be specified directly in the [dbmodules]

section to control where database modules are loaded from:

**db_module_dir**

    This tag controls where the plugin system looks for database

    modules.  The value should be an absolute path.

.. _logging:

[logging]

~~~~~~~~~

The [logging] section indicates how :ref:`krb5kdc(8)` and

:ref:`kadmind(8)` perform logging.  It may contain the following

relations:

**admin_server**

    Specifies how :ref:`kadmind(8)` performs logging.

**kdc**

    Specifies how :ref:`krb5kdc(8)` performs logging.

**default**

    Specifies how either daemon performs logging in the absence of

    relations specific to the daemon.

**debug**

    (Boolean value.)  Specifies whether debugging messages are

    included in log outputs other than SYSLOG.  Debugging messages are

    always included in the system log output because syslog performs

    its own priority filtering.  The default value is false.  New in

    release 1.15.

Logging specifications may have the following forms:

**FILE=**\ *filename* or **FILE:**\ *filename*

    This value causes the daemon's logging messages to go to the

    *filename*.  If the ``=`` form is used, the file is overwritten.

    If the ``:`` form is used, the file is appended to.

**STDERR**

    This value causes the daemon's logging messages to go to its

    standard error stream.

**CONSOLE**

    This value causes the daemon's logging messages to go to the

    console, if the system supports it.

**DEVICE=**\ *<devicename>*

    This causes the daemon's logging messages to go to the specified

    device.

**SYSLOG**\ [\ **:**\ *severity*\ [\ **:**\ *facility*\ ]]

    This causes the daemon's logging messages to go to the system log.

    For backward compatibility, a severity argument may be specified,

    and must be specified in order to specify a facility.  This

    argument will be ignored.

    The facility argument specifies the facility under which the

    messages are logged.  This may be any of the following facilities

    supported by the syslog(3) call minus the LOG\_ prefix: **KERN**,

    **USER**, **MAIL**, **DAEMON**, **AUTH**, **LPR**, **NEWS**,

    **UUCP**, **CRON**, and **LOCAL0** through **LOCAL7**.  If no

    facility is specified, the default is **AUTH**.

In the following example, the logging messages from the KDC will go to

the console and to the system log under the facility LOG_DAEMON, and

the logging messages from the administrative server will be appended

to the file ``/var/adm/kadmin.log`` and sent to the device

``/dev/tty04``. ::

    [logging]

        kdc = CONSOLE

        kdc = SYSLOG:INFO:DAEMON

        admin_server = FILE:/var/adm/kadmin.log

        admin_server = DEVICE=/dev/tty04

If no logging specification is given, the default is to use syslog.

To disable logging entirely, specify ``default = DEVICE=/dev/null``.

.. _otp:

[otp]

~~~~~

Each subsection of [otp] is the name of an OTP token type.  The tags

within the subsection define the configuration required to forward a

One Time Password request to a RADIUS server.

For each token type, the following tags may be specified:

**server**

    This is the server to send the RADIUS request to.  It can be a

    hostname with optional port, an ip address with optional port, or

    a Unix domain socket address.  The default is

    |kdcdir|\ ``/<name>.socket``.

**secret**

    This tag indicates a filename (which may be relative to |kdcdir|)

    containing the secret used to encrypt the RADIUS packets.  The

    secret should appear in the first line of the file by itself;

    leading and trailing whitespace on the line will be removed.  If

    the value of **server** is a Unix domain socket address, this tag

    is optional, and an empty secret will be used if it is not

    specified.  Otherwise, this tag is required.

**timeout**

    An integer which specifies the time in seconds during which the

    KDC should attempt to contact the RADIUS server.  This tag is the

    total time across all retries and should be less than the time

    which an OTP value remains valid for.  The default is 5 seconds.

**retries**

    This tag specifies the number of retries to make to the RADIUS

    server.  The default is 3 retries (4 tries).

**strip_realm**

    If this tag is ``true``, the principal without the realm will be

    passed to the RADIUS server.  Otherwise, the realm will be

    included.  The default value is ``true``.

**indicator**

    This tag specifies an authentication indicator to be included in

    the ticket if this token type is used to authenticate.  This

    option may be specified multiple times.  (New in release 1.14.)

In the following example, requests are sent to a remote server via UDP::

    [otp]

        MyRemoteTokenType = {

            server = radius.mydomain.com:1812

            secret = SEmfiajf42$

            timeout = 15

            retries = 5

            strip_realm = true

        }

An implicit default token type named ``DEFAULT`` is defined for when

the per-principal configuration does not specify a token type.  Its

configuration is shown below.  You may override this token type to

something applicable for your situation::

    [otp]

        DEFAULT = {

            strip_realm = false

        }

PKINIT options

--------------

.. note::

          The following are pkinit-specific options.  These values may

          be specified in [kdcdefaults] as global defaults, or within

          a realm-specific subsection of [realms].  Also note that a

          realm-specific value over-rides, does not add to, a generic

          [kdcdefaults] specification.  The search order is:

1. realm-specific subsection of [realms]::

       [realms]

           EXAMPLE.COM = {

               pkinit_anchors = FILE:/usr/local/example.com.crt

           }

2. generic value in the [kdcdefaults] section::

       [kdcdefaults]

           pkinit_anchors = DIR:/usr/local/generic_trusted_cas/

For information about the syntax of some of these options, see

:ref:`Specifying PKINIT identity information <pkinit_identity>` in

:ref:`krb5.conf(5)`.

**pkinit_anchors**

    Specifies the location of trusted anchor (root) certificates which

    the KDC trusts to sign client certificates.  This option is

    required if pkinit is to be supported by the KDC.  This option may

    be specified multiple times.

**pkinit_dh_min_bits**

    Specifies the minimum number of bits the KDC is willing to accept

    for a client's Diffie-Hellman key.  The default is 2048.

**pkinit_allow_upn**

    Specifies that the KDC is willing to accept client certificates

    with the Microsoft UserPrincipalName (UPN) Subject Alternative

    Name (SAN).  This means the KDC accepts the binding of the UPN in

    the certificate to the Kerberos principal name.  The default value

    is false.

    Without this option, the KDC will only accept certificates with

    the id-pkinit-san as defined in :rfc:`4556`.  There is currently

    no option to disable SAN checking in the KDC.

**pkinit_eku_checking**

    This option specifies what Extended Key Usage (EKU) values the KDC

    is willing to accept in client certificates.  The values

    recognized in the kdc.conf file are:

    **kpClientAuth**

        This is the default value and specifies that client

        certificates must have the id-pkinit-KPClientAuth EKU as

        defined in :rfc:`4556`.

    **scLogin**

        If scLogin is specified, client certificates with the

        Microsoft Smart Card Login EKU (id-ms-kp-sc-logon) will be

        accepted.

    **none**

        If none is specified, then client certificates will not be

        checked to verify they have an acceptable EKU.  The use of

        this option is not recommended.

**pkinit_identity**

    Specifies the location of the KDC's X.509 identity information.

    This option is required if pkinit is to be supported by the KDC.

**pkinit_indicator**

    Specifies an authentication indicator to include in the ticket if

    pkinit is used to authenticate.  This option may be specified

    multiple times.  (New in release 1.14.)

**pkinit_pool**

    Specifies the location of intermediate certificates which may be

    used by the KDC to complete the trust chain between a client's

    certificate and a trusted anchor.  This option may be specified

    multiple times.

**pkinit_revoke**

    Specifies the location of Certificate Revocation List (CRL)

    information to be used by the KDC when verifying the validity of

    client certificates.  This option may be specified multiple times.

**pkinit_require_crl_checking**

    The default certificate verification process will always check the

    available revocation information to see if a certificate has been

    revoked.  If a match is found for the certificate in a CRL,

    verification fails.  If the certificate being verified is not

    listed in a CRL, or there is no CRL present for its issuing CA,

    and **pkinit_require_crl_checking** is false, then verification

    succeeds.

    However, if **pkinit_require_crl_checking** is true and there is

    no CRL information available for the issuing CA, then verification

    fails.

    **pkinit_require_crl_checking** should be set to true if the

    policy is such that up-to-date CRLs must be present for every CA.

**pkinit_require_freshness**

    Specifies whether to require clients to include a freshness token

    in PKINIT requests.  The default value is false.  (New in release

    1.17.)

.. _Encryption_types:

Encryption types

----------------

Any tag in the configuration files which requires a list of encryption

types can be set to some combination of the following strings.

Encryption types marked as "weak" are available for compatibility but

not recommended for use.

==================================================== =========================================================

des3-cbc-raw                                         Triple DES cbc mode raw (weak)

des3-cbc-sha1 des3-hmac-sha1 des3-cbc-sha1-kd        Triple DES cbc mode with HMAC/sha1

aes256-cts-hmac-sha1-96 aes256-cts aes256-sha1       AES-256 CTS mode with 96-bit SHA-1 HMAC

aes128-cts-hmac-sha1-96 aes128-cts aes128-sha1       AES-128 CTS mode with 96-bit SHA-1 HMAC

aes256-cts-hmac-sha384-192 aes256-sha2               AES-256 CTS mode with 192-bit SHA-384 HMAC

aes128-cts-hmac-sha256-128 aes128-sha2               AES-128 CTS mode with 128-bit SHA-256 HMAC

arcfour-hmac rc4-hmac arcfour-hmac-md5               RC4 with HMAC/MD5

arcfour-hmac-exp rc4-hmac-exp arcfour-hmac-md5-exp   Exportable RC4 with HMAC/MD5 (weak)

camellia256-cts-cmac camellia256-cts                 Camellia-256 CTS mode with CMAC

camellia128-cts-cmac camellia128-cts                 Camellia-128 CTS mode with CMAC

des3                                                 The triple DES family: des3-cbc-sha1

aes                                                  The AES family: aes256-cts-hmac-sha1-96, aes128-cts-hmac-sha1-96, aes256-cts-hmac-sha384-192, and aes128-cts-hmac-sha256-128

rc4                                                  The RC4 family: arcfour-hmac

camellia                                             The Camellia family: camellia256-cts-cmac and camellia128-cts-cmac

==================================================== =========================================================

The string **DEFAULT** can be used to refer to the default set of

types for the variable in question.  Types or families can be removed

from the current list by prefixing them with a minus sign ("-").

Types or families can be prefixed with a plus sign ("+") for symmetry;

it has the same meaning as just listing the type or family.  For

example, "``DEFAULT -rc4``" would be the default set of encryption

types with RC4 types removed, and "``des3 DEFAULT``" would be the

default set of encryption types with triple DES types moved to the

front.

While **aes128-cts** and **aes256-cts** are supported for all Kerberos

operations, they are not supported by very old versions of our GSSAPI

implementation (krb5-1.3.1 and earlier).  Services running versions of

krb5 without AES support must not be given keys of these encryption

types in the KDC database.

The **aes128-sha2** and **aes256-sha2** encryption types are new in

release 1.15.  Services running versions of krb5 without support for