NAME

       kinit - obtain and cache Kerberos ticket-granting ticket

SYNOPSIS

       kinit [-V] [-l lifetime] [-s start_time] [-r renewable_life] [-p | -P] [-f | -F] [-a] [-A]
       [-C] [-E] [-v] [-R] [-k [-t keytab_file]]  [-c  cache_name]  [-n]  [-S  service_name]  [-I
       input_ccache] [-T armor_ccache] [-X attribute[=value]] [principal]

DESCRIPTION

       kinit obtains and caches an initial ticket-granting ticket for principal.  If principal is
       absent, kinit chooses an appropriate principal name based  on  existing  credential  cache
       contents or the local username of the user invoking kinit.  Some options modify the choice
       of principal name.

OPTIONS

       -V     display verbose output.

       -l lifetime
              (duration string.)  Requests a ticket with the lifetime lifetime.

              For example, kinit -l 5:30 or kinit -l 5h30m.

              If the -l option is not specified, the default ticket lifetime (configured by  each
              site)  is  used.   Specifying  a  ticket  lifetime  longer  than the maximum ticket
              lifetime (configured by each site) will not override the configured maximum  ticket
              lifetime.

       -s start_time
              (duration string.)  Requests a postdated ticket.  Postdated tickets are issued with
              the invalid flag set, and need to be resubmitted to the KDC for  validation  before
              use.

              start_time specifies the duration of the delay before the ticket can become valid.

       -r renewable_life
              (duration   string.)    Requests  renewable  tickets,  with  a  total  lifetime  of
              renewable_life.

       -f     requests forwardable tickets.

       -F     requests non-forwardable tickets.

       -p     requests proxiable tickets.

       -P     requests non-proxiable tickets.

       -a     requests tickets restricted to the host's local address[es].

       -A     requests tickets not restricted by address.

       -C     requests canonicalization of the principal name, and allows the KDC to reply with a
              different client principal from the one requested.

       -E     treats the principal name as an enterprise name.

       -v     requests  that  the ticket-granting ticket in the cache (with the invalid flag set)
              be passed to the KDC for validation.  If the ticket is within  its  requested  time
              range, the cache is replaced with the validated ticket.

       -R     requests renewal of the ticket-granting ticket.  Note that an expired ticket cannot
              be renewed, even if the ticket is still within its renewable life.

              Note that renewable tickets that have expired as reported by klist(1) may sometimes
              be renewed using this option, because the KDC applies a grace period to account for
              client-KDC clock skew.  See krb5.conf(5) clockskew setting.

       -k [-i | -t keytab_file]
              requests a ticket, obtained from a key in the local host's keytab.  The location of
              the  keytab  may be specified with the -t keytab_file option, or with the -i option
              to specify the use of the default client keytab; otherwise the default keytab  will
              be  used.   By  default,  a  host  ticket  for the local host is requested, but any
              principal may be specified.  On a KDC, the special keytab location KDB: can be used
              to  indicate  that kinit should open the KDC database and look up the key directly.
              This permits an administrator to obtain tickets  as  any  principal  that  supports
              authentication based on the key.

       -n     Requests anonymous processing.  Two types of anonymous principals are supported.

              For   fully   anonymous  Kerberos,  configure  pkinit  on  the  KDC  and  configure
              pkinit_anchors in the client's  krb5.conf(5).   Then  use  the  -n  option  with  a
              principal of the form @REALM (an empty principal name followed by the at-sign and a
              realm name).  If permitted by the KDC, an anonymous ticket will be returned.

              A second form of anonymous tickets is supported; these realm-exposed  tickets  hide
              the identity of the client but not the client's realm.  For this mode, use kinit -n
              with a normal principal name.  If supported by the  KDC,  the  principal  (but  not
              realm) will be replaced by the anonymous principal.

              As of release 1.8, the MIT Kerberos KDC only supports fully anonymous operation.

       -I input_ccache
          Specifies  the  name  of  a  credentials  cache  that  already contains a ticket.  When
          obtaining that ticket, if information about how  that  ticket  was  obtained  was  also
          stored  to  the  cache, that information will be used to affect how new credentials are
          obtained, including preselecting the same methods of authenticating to the KDC.

       -T armor_ccache
              Specifies the name of a credentials cache  that  already  contains  a  ticket.   If
              supported  by  the  KDC,  this  cache will be used to armor the request, preventing
              offline dictionary attacks and allowing the  use  of  additional  preauthentication
              mechanisms.   Armoring  also  makes  sure  that  the  response  from the KDC is not
              modified in transit.

       -c cache_name
              use cache_name as the Kerberos 5 credentials  (ticket)  cache  location.   If  this
              option is not used, the default cache location is used.

              The default cache location may vary between systems.  If the KRB5CCNAME environment
              variable is set, its value is used to locate the default  cache.   If  a  principal
              name  is specified and the type of the default cache supports a collection (such as
              the DIR type), an existing  cache  containing  credentials  for  the  principal  is
              selected or a new one is created and becomes the new primary cache.  Otherwise, any
              existing contents of the default cache are destroyed by kinit.

       -S service_name
              specify an alternate service name to use when getting initial tickets.

       -X attribute[=value]
              specify  a  pre-authentication  attribute  and   value   to   be   interpreted   by
              pre-authentication  modules.   The  acceptable attribute and value values vary from
              module to module.  This option may be specified multiple times to specify  multiple
              attributes.  If no value is specified, it is assumed to be "yes".

              The following attributes are recognized by the PKINIT pre-authentication mechanism:

              X509_user_identity=value
                     specify where to find user's X509 identity information

              X509_anchors=value
                     specify where to find trusted X509 anchor information

              flag_RSA_PROTOCOL[=yes]
                     specify use of RSA, rather than the default Diffie-Hellman protocol

              disable_freshness[=yes]
                     disable sending freshness tokens (for testing purposes only)

ENVIRONMENT

       See kerberos(7) for a description of Kerberos environment variables.

FILES

       FILE:/tmp/krb5cc_%{uid}
              default location of Kerberos 5 credentials cache

       FILE:/etc/krb5.keytab
              default location for the local host's keytab.

SEE ALSO

       klist(1), kdestroy(1), kerberos(7)

AUTHOR

       MIT

COPYRIGHT

       1985-2019, MIT