
KRB5.CONF(5)               UNIX Programmer's Manual               KRB5.CONF(5)

NNAAMMEE
     kkrrbb55..ccoonnff - configuration file for Kerberos 5

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DDEESSCCRRIIPPTTIIOONN
     The kkrrbb55..ccoonnff file specifies several configuration parameters for the
     Kerberos 5 library, as well as for some programs.

     The file consists of one or more sections, containing a number of bind-
     ings.  The value of each binding can be either a string or a list of oth-
     er bindings.  The grammar looks like:

           file:
                   /* empty */
                   sections

           sections:
                   section sections
                   section

           section:
                   '[' section_name ']' bindings

           section_name:
                   STRING

           bindings:
                   binding bindings
                   binding

           binding:
                   name '=' STRING
                   name '=' '{' bindings '}'

           name:
                   STRING

     STRINGs consists of one or more non-whitespace characters.

     STRINGs that are specified later in this man-page uses the following no-
     tation.

           boolean
                values can be either yes/true or no/false.

           time
                values can be a list of year, month, day, hour, min, second.
                Example: 1 month 2 days 30 min.  If no unit is given, seconds
                is assumed.

           etypes
                valid encryption types are: des-cbc-crc, des-cbc-md4, des-cbc-
                md5, des3-cbc-sha1, arcfour-hmac-md5, aes128-cts-hmac-sha1-96,
                and aes256-cts-hmac-sha1-96 .

           address
                an address can be either a IPv4 or a IPv6 address.

     Currently recognised sections and bindings are:

           [appdefaults]
                Specifies the default values to be used for Kerberos applica-
                tions.  You can specify defaults per application, realm, or a
                combination of these.  The preference order is:
                1.   _a_p_p_l_i_c_a_t_i_o_n _r_e_a_l_m _o_p_t_i_o_n
                2.   _a_p_p_l_i_c_a_t_i_o_n _o_p_t_i_o_n
                3.   _r_e_a_l_m _o_p_t_i_o_n
                4.   _o_p_t_i_o_n

                The supported options are:

                      forwardable = _b_o_o_l_e_a_n
                           When obtaining initial credentials, make the cre-
                           dentials forwardable.

                      proxiable = _b_o_o_l_e_a_n
                           When obtaining initial credentials, make the cre-
                           dentials proxiable.

                      no-addresses = _b_o_o_l_e_a_n
                           When obtaining initial credentials, request them
                           for an empty set of addresses, making the tickets
                           valid from any address.

                      ticket_lifetime = _t_i_m_e
                           Default ticket lifetime.

                      renew_lifetime = _t_i_m_e
                           Default renewable ticket lifetime.

                      encrypt = _b_o_o_l_e_a_n
                           Use encryption, when available.

                      forward = _b_o_o_l_e_a_n
                           Forward credentials to remote host (for rsh(1),
                           telnet(1),  etc).

           [libdefaults]

                      default_realm = _R_E_A_L_M
                           Default realm to use, this is also known as your
                           ``local realm''. The default is the result of
                           kkrrbb55__ggeett__hhoosstt__rreeaallmm(_l_o_c_a_l _h_o_s_t_n_a_m_e).

                      clockskew = _t_i_m_e
                           Maximum time differential (in seconds) allowed when
                           comparing times.  Default is 300 seconds (five min-
                           utes).

                      kdc_timeout = _t_i_m_e
                           Maximum time to wait for a reply from the kdc, de-
                           fault is 3 seconds.

                      v4_name_convert

                      v4_instance_resolve
                           These are described in the krb5_425_conv_princi-
                           pal(3) manual page.

                      capath = {

                                 _d_e_s_t_i_n_a_t_i_o_n_-_r_e_a_l_m = _n_e_x_t_-_h_o_p_-_r_e_a_l_m

                                 ...

                                 }


                           This is deprecated, see the capaths section below.

                      default_cc_name = _c_c_n_a_m_e
                           the default credentials cache name.  The string can
                           contain variables that are expanded on runtime.
                           Only support variable now is %{uid} that expands to
                           the current user id.

                      default_etypes = _e_t_y_p_e_s _._._.
                           A list of default encryption types to use.

                      default_etypes_des = _e_t_y_p_e_s _._._.
                           A list of default encryption types to use when re-
                           questing a DES credential.

                      default_keytab_name = _k_e_y_t_a_b
                           The keytab to use if no other is specified, default
                           is ``FILE:/etc/krb5.keytab''.

                      dns_lookup_kdc = _b_o_o_l_e_a_n
                           Use DNS SRV records to lookup KDC services loca-
                           tion.

                      dns_lookup_realm = _b_o_o_l_e_a_n
                           Use DNS TXT records to lookup domain to realm map-
                           pings.

                      kdc_timesync = _b_o_o_l_e_a_n
                           Try to keep track of the time differential between
                           the local machine and the KDC, and then compensate
                           for that when issuing requests.

                      max_retries = _n_u_m_b_e_r
                           The max number of times to try to contact each KDC.

                      large_msg_size = _n_u_m_b_e_r
                           The threshold where protocols with tiny maximum
                           message sizes are not considered usable to send
                           messages to the KDC.

                      ticket_lifetime = _t_i_m_e
                           Default ticket lifetime.

                      renew_lifetime = _t_i_m_e
                           Default renewable ticket lifetime.

                      forwardable = _b_o_o_l_e_a_n
                           When obtaining initial credentials, make the cre-
                           dentials forwardable.  This option is also valid in
                           the [realms] section.

                      proxiable = _b_o_o_l_e_a_n
                           When obtaining initial credentials, make the cre-
                           dentials proxiable.  This option is also valid in
                           the [realms] section.

                      verify_ap_req_nofail = _b_o_o_l_e_a_n
                           If enabled, failure to verify credentials against a
                           local key is a fatal error.  The application has to
                           be able to read the corresponding service key for
                           this to work.  Some applications, like su(1),  en-
                           able this option unconditionally.

                      warn_pwexpire = _t_i_m_e
                           How soon to warn for expiring password.  Default is

                           seven days.

                      http_proxy = _p_r_o_x_y_-_s_p_e_c
                           A HTTP-proxy to use when talking to the KDC via
                           HTTP.

                      dns_proxy = _p_r_o_x_y_-_s_p_e_c
                           Enable using DNS via HTTP.

                      extra_addresses = _a_d_d_r_e_s_s _._._.
                           A list of addresses to get tickets for along with
                           all local addresses.

                      time_format = _s_t_r_i_n_g
                           How to print time strings in logs, this string is
                           passed to strftime(3).

                      date_format = _s_t_r_i_n_g
                           How to print date strings in logs, this string is
                           passed to strftime(3).

                      log_utc = _b_o_o_l_e_a_n
                           Write log-entries using UTC instead of your local
                           time zone.

                      scan_interfaces = _b_o_o_l_e_a_n
                           Scan all network interfaces for addresses, as op-
                           posed to simply using the address associated with
                           the system's host name.

                      fcache_version = _i_n_t
                           Use file credential cache format version specified.

                      krb4_get_tickets = _b_o_o_l_e_a_n
                           Also get Kerberos 4 tickets in kkiinniitt, llooggiinn, and
                           other programs.  This option is also valid in the
                           [realms] section.

                      fcc-mit-ticketflags = _b_o_o_l_e_a_n
                           Use MIT compatible format for file credential
                           cache.  It's the field ticketflags that is stored
                           in reverse bit order for older than Heimdal 0.7.
                           Setting this flag to TRUE make it store the MIT
                           way, this is default for Heimdal 0.7.

           [domain_realm]
                This is a list of mappings from DNS domain to Kerberos realm.
                Each binding in this section looks like:

                      domain = realm

                The domain can be either a full name of a host or a trailing
                component, in the latter case the domain-string should start
                with a period.  The trailing component only matches hosts that
                are in the same domain, ie ``.example.com'' matches
                ``foo.example.com'', but not ``foo.test.example.com''.

                The realm may be the token `dns_locate', in which case the ac-
                tual realm will be determined using DNS (independently of the
                setting of the `dns_lookup_realm' option).

           [realms]

                      _R_E_A_L_M = {



                                 kdc = _[_s_e_r_v_i_c_e_/_]_h_o_s_t_[_:_p_o_r_t_]
                                      Specifies a list of kdcs for this realm.
                                      If the optional _p_o_r_t is absent, the de-
                                      fault value for the ``kerberos/udp''
                                      ``kerberos/tcp'', and ``http/tcp'' port
                                      (depending on service) will be used.
                                      The kdcs will be used in the order that
                                      they are specified.

                                      The optional _s_e_r_v_i_c_e specifies over what
                                      medium the kdc should be contacted.
                                      Possible services are ``udp'', ``tcp'',
                                      and ``http''. Http can also be written
                                      as ``http://''. Default service is
                                      ``udp'' and ``tcp''.

                                 admin_server = _h_o_s_t_[_:_p_o_r_t_]
                                      Specifies the admin server for this
                                      realm, where all the modifications to
                                      the database are performed.

                                 kpasswd_server = _h_o_s_t_[_:_p_o_r_t_]
                                      Points to the server where all the pass-
                                      word changes are performed.  If there is
                                      no such entry, the kpasswd port on the
                                      admin_server host will be tried.

                                 krb524_server = _h_o_s_t_[_:_p_o_r_t_]
                                      Points to the server that does 524 con-
                                      versions.  If it is not mentioned, the
                                      krb524 port on the kdcs will be tried.

                                 v4_instance_convert

                                 v4_name_convert

                                 default_domain
                                      See krb5_425_conv_principal(3).

                                 tgs_require_subkey
                                      a boolan variable that defaults to
                                      false.  Old DCE secd (pre 1.1) might
                                      need this to be true.

                      }

           [capaths]

                      _c_l_i_e_n_t_-_r_e_a_l_m = {

                                 _s_e_r_v_e_r_-_r_e_a_l_m = _h_o_p_-_r_e_a_l_m _._._.
                                      This serves two purposes. First the
                                      first listed _h_o_p_-_r_e_a_l_m tells a client
                                      which realm it should contact in order
                                      to ultimately obtain credentials for a
                                      service in the _s_e_r_v_e_r_-_r_e_a_l_m. Secondly,
                                      it tells the KDC (and other servers)
                                      which realms are allowed in a multi-hop
                                      traversal from _c_l_i_e_n_t_-_r_e_a_l_m to _s_e_r_v_e_r_-
                                      _r_e_a_l_m. Except for the client case, the
                                      order of the realms are not important.

                      _}



           [logging]

                      _e_n_t_i_t_y = _d_e_s_t_i_n_a_t_i_o_n
                           Specifies that _e_n_t_i_t_y should use the specified
                           destination for logging.  See the krb5_openlog(3)
                           manual page for a list of defined destinations.

           [kdc]

                      database = {

                                 dbname = _D_A_T_A_B_A_S_E_N_A_M_E
                                      Use this database for this realm.  See
                                      the info documetation how to configure
                                      diffrent database backends.

                                 realm = _R_E_A_L_M
                                      Specifies the realm that will be stored
                                      in this database.  It realm isn't set,
                                      it will used as the default database,
                                      there can only be one entry that doesn't
                                      have a realm stanza.

                                 mkey_file = _F_I_L_E_N_A_M_E
                                      Use this keytab file for the master key
                                      of this database.  If not specified
                                      _D_A_T_A_B_A_S_E_N_A_M_E.mkey will be used.

                                 acl_file = PA FILENAME
                                      Use this file for the ACL list of this
                                      database.

                                 log_file = _F_I_L_E_N_A_M_E
                                      Use this file as the log of changes per-
                                      formed to the database.  This file is
                                      used by iipprrooppdd--mmaasstteerr for propagating
                                      changes to slaves.

                      }

                      max-request = _S_I_Z_E
                           Maximum size of a kdc request.

                      require-preauth = _B_O_O_L
                           If set pre-authentication is required.  Since krb4
                           requests are not pre-authenticated they will be re-
                           jected.

                      ports = _l_i_s_t _o_f _p_o_r_t_s
                           List of ports the kdc should listen to.

                      addresses = _l_i_s_t _o_f _i_n_t_e_r_f_a_c_e_s
                           List of addresses the kdc should bind to.

                      enable-kerberos4 = _B_O_O_L
                           Turn on Kerberos 4 support.

                      v4-realm = _R_E_A_L_M
                           To what realm v4 requests should be mapped.

                      enable-524 = _B_O_O_L
                           Should the Kerberos 524 converting facility be
                           turned on.  Default is the same as _e_n_a_b_l_e_-


                           _k_e_r_b_e_r_o_s_4.

                      enable-http = _B_O_O_L
                           Should the kdc answer kdc-requests over http.

                      enable-kaserver = _B_O_O_L
                           If this kdc should emulate the AFS kaserver.

                      check-ticket-addresses = _B_O_O_L
                           Verify the addresses in the tickets used in tgs re-
                           quests.

                      allow-null-ticket-addresses = _B_O_O_L
                           Allow address-less tickets.

                      allow-anonymous = _B_O_O_L
                           If the kdc is allowed to hand out anonymous tick-
                           ets.

                      encode_as_rep_as_tgs_rep = _B_O_O_L
                           Encode as-rep as tgs-rep tobe compatible with mis-
                           takes older DCE secd did.

                      kdc_warn_pwexpire = _T_I_M_E
                           The time before expiration that the user should be
                           warned that her password is about to expire.

                      logging = _L_o_g_g_i_n_g
                           What type of logging the kdc should use, see also
                           [logging]/kdc.

                      use_2b = {

                                 _p_r_i_n_c_i_p_a_l = _B_O_O_L
                                      boolean value if the 524 daemon should
                                      return AFS 2b tokens for _p_r_i_n_c_i_p_a_l.

                                 ...

                      }

                      hdb-ldap-structural-object _s_t_r_u_c_t_u_r_a_l _o_b_j_e_c_t
                           If the LDAP backend is used for storing principals,
                           this is the structural object that will be used
                           when creating and when reading objects.  The de-
                           fault value is account .

                      hdb-ldap-create-base _c_r_e_a_t_i_o_n _d_n
                           is the dn that will be appended to the principal
                           when creating entries.  Default value is the search
                           dn.

           [kadmin]

                      require-preauth = _B_O_O_L
                           If pre-authentication is required to talk to the
                           kadmin server.

                      password_lifetime = _t_i_m_e
                           If a principal already have its password set for
                           expiration, this is the time it will be valid for
                           after a change.

                      default_keys = _k_e_y_t_y_p_e_s_._._.
                           For each entry in _d_e_f_a_u_l_t___k_e_y_s try to parse it as a
                           sequence of _e_t_y_p_e_:_s_a_l_t_t_y_p_e_:_s_a_l_t syntax of this if
                           something like:

                           [(des|des3|etype):](pw-salt|afs3-salt)[:string]

                           If _e_t_y_p_e is omitted it means everything, and if
                           string is omitted it means the default salt string
                           (for that principal and encryption type).  Addi-
                           tional special values of keytypes are:

                                 v5   The Kerberos 5 salt _p_w_-_s_a_l_t

                                 v4   The Kerberos 4 salt _d_e_s_:_p_w_-_s_a_l_t_:

                      use_v4_salt = _B_O_O_L
                           When true, this is the same as

                           _d_e_f_a_u_l_t___k_e_y_s _= _d_e_s_3_:_p_w_-_s_a_l_t _v_4

                           and is only left for backwards compatibility.

EENNVVIIRROONNMMEENNTT
     KRB5_CONFIG points to the configuration file to read.

FFIILLEESS
     /etc/krb5.conf  configuration file for Kerberos 5.

EEXXAAMMPPLLEESS
           [libdefaults]
                   default_realm = FOO.SE
           [domain_realm]
                   .foo.se = FOO.SE
                   .bar.se = FOO.SE
           [realms]
                   FOO.SE = {
                           kdc = kerberos.foo.se
                           v4_name_convert = {
                                   rcmd = host
                           }
                           v4_instance_convert = {
                                   xyz = xyz.bar.se
                           }
                           default_domain = foo.se
                   }
           [logging]
                   kdc = FILE:/var/heimdal/kdc.log
                   kdc = SYSLOG:INFO
                   default = SYSLOG:INFO:USER

DDIIAAGGNNOOSSTTIICCSS
     Since kkrrbb55..ccoonnff is read and parsed by the krb5 library, there is not a
     lot of opportunities for programs to report parsing errors in any useful
     format.  To help overcome this problem, there is a program
     vveerriiffyy__kkrrbb55__ccoonnff that reads kkrrbb55..ccoonnff and tries to emit useful diagnos-
     tics from parsing errors.  Note that this program does not have any way
     of knowing what options are actually used and thus cannot warn about un-
     known or misspelled ones.

SSEEEE AALLSSOO
     kinit(1),  krb5_425_conv_principal(3),  krb5_openlog(3),  strftime(3),
     verify_krb5_conf(8)

 HEIMDAL                          May 4, 2005                                8
