— Kerberos 5
file | --config-file=file]
[-p | --no-require-preauth]
[-H | --enable-http]
[-r string | --v4-realm=string]
[-P portspec | --ports=portspec]
[--addresses=list of addresses]
serves requests for tickets. When it starts, it
first checks the flags passed, any options that are not specified with a
command line flag are taken from a config file, or from a default compiled-in
- Specifies the location of the config file, the default is
/etc/heimdal-kdc/kdc.conf. This is the only
value that can't be specified in the config file.
- Turn off the requirement for pre-autentication in the
initial AS-REQ for all principals. The use of pre-authentication makes it
more difficult to do offline password attacks. You might want to turn it
off if you have clients that don't support pre-authentication. Since the
version 4 protocol doesn't support any pre-authentication, serving version
4 clients is just about the same as not requiring pre-athentication. The
default is to require pre-authentication. Adding the require-preauth per
principal is a more flexible way of handling this.
- Gives an upper limit on the size of the requests that the
kdc is willing to handle.
- Makes the kdc listen on port 80 and handle requests
encapsulated in HTTP.
- What realm this server should act as when dealing with
version 4 requests. The database can contain any number of realms, but
since the version 4 protocol doesn't contain a realm for the server, it
must be explicitly specified. The default is whatever is returned by
krb_get_lrealm(). This option is only
available if the KDC has been compiled with version 4 support.
- Specifies the set of ports the KDC should listen on. It is
given as a white-space separated list of services or port numbers.
- The list of addresses to listen for requests on. By
default, the kdc will listen on all the locally configured addresses. If
only a subset is desired, or the automatic detection fails, this option
might be used.
- detach from pty and run as a daemon.
- disable all des encryption types, makes the kdc not use
All activities are logged to one or more destinations, see
. The entity used for logging is
The configuration file has the same syntax as
, but will be read before
, so it may override settings found
there. Options specific to the KDC only are found in the “[kdc]”
section. All the command-line options can preferably be added in the
configuration file. The only difference is the pre-authentication flag, which
has to be specified as:
require-preauth = no
(in fact you can specify the option as
And there are some configuration options which do not have command-line
- turn on support for digest processing in the KDC. The
default is FALSE.
- Check the addresses in the ticket when processing TGS
requests. The default is TRUE.
- Permit tickets with no addresses. This option is only
relevant when check-ticket-addresses is TRUE.
- Permit anonymous tickets with no addresses.
- Maximum packet size the UDP rely that the KDC will
transmit, instead the KDC sends back a reply telling the client to use TCP
- This controls how KDC requests with the
disable-transited-check flag are handled. It can
be one of:
- Always check transited encoding, this is the
- Currently this is identical to
always-check. In a future release, it will be
possible to mark a principal as able to handle unchecked
- Always do what the client asked. In a future release,
it will be possible to force a check per principal.
- encode_as_rep_as_tgs_rep =
- Encode AS-Rep as TGS-Rep to be bug-compatible with old DCE
code. The Heimdal clients allow both.
- kdc_warn_pwexpire =
- How long before password/principal expiration the KDC
should start sending out warning messages.
The configuration file is only read when the kdc
started. If changes made to the configuration file are to take effect, the
needs to be restarted.
An example of a config file:
require-preauth = no
v4-realm = FOO.SE
If the machine running the KDC has new addresses added to it, the KDC will have
to be restarted to listen to them. The reason it doesn't just listen to
wildcarded (like INADDR_ANY) addresses, is that the replies has to come from
the same address they were sent to, and most OS:es doesn't pass this
information to the application. If your normal mode of operation require that
you add and remove addresses, the best option is probably to listen to a
wildcarded TCP socket, and make sure your clients use TCP to connect. For
instance, this will listen to IPv4 TCP port 88 only:
kdc --addresses=0.0.0.0 --ports="88/tcp"
There should be a way to specify protocol, port, and address triplets, not just
addresses and protocol, port tuples.