1.\" Copyright (c) 2003 Kungliga Tekniska H�gskolan
2.\" (Royal Institute of Technology, Stockholm, Sweden).
3.\" All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\"
9.\" 1. Redistributions of source code must retain the above copyright
10.\" notice, this list of conditions and the following disclaimer.
11.\"
12.\" 2. Redistributions in binary form must reproduce the above copyright
13.\" notice, this list of conditions and the following disclaimer in the
14.\" documentation and/or other materials provided with the distribution.
15.\"
16.\" 3. Neither the name of the Institute nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\" $Id: kdc.8,v 1.23 2003/04/06 17:48:40 lha Exp $
33.\"
34.Dd August 22, 2002
35.Dt KDC 8
36.Os HEIMDAL
37.Sh NAME
38.Nm kdc
39.Nd Kerberos 5 server
40.Sh SYNOPSIS
41.Nm
42.Oo Fl c Ar file \*(Ba Xo
43.Fl -config-file= Ns Ar file
44.Xc
45.Oc
46.Op Fl p | Fl -no-require-preauth
47.Op Fl -max-request= Ns Ar size
48.Op Fl H | Fl -enable-http
49.Op Fl -no-524
50.Op Fl -kerberos4
51.Op Fl -kerberos4-cross-realm
52.Oo Fl r Ar string \*(Ba Xo
53.Fl -v4-realm= Ns Ar string
54.Xc
55.Oc
56.Op Fl K | Fl -kaserver
57.Oo Fl P Ar portspec \*(Ba Xo
58.Fl -ports= Ns Ar portspec
59.Xc
60.Oc
61.Op Fl -detach
62.Op Fl -addresses= Ns Ar list of addresses
63.Sh DESCRIPTION
64.Nm
65serves requests for tickets.
66When it starts, it first checks the flags passed, any options that are
67not specified with a command line flag are taken from a config file,
68or from a default compiled-in value.
69.Pp
70Options supported:
71.Bl -tag -width Ds
72.It Xo
73.Fl c Ar file ,
74.Fl -config-file= Ns Ar file
75.Xc
76Specifies the location of the config file, the default is
77.Pa /var/heimdal/kdc.conf .
78This is the only value that can't be specified in the config file.
79.It Xo
80.Fl p ,
81.Fl -no-require-preauth
82.Xc
83Turn off the requirement for pre-autentication in the initial AS-REQ
84for all principals.
85The use of pre-authentication makes it more difficult to do offline
86password attacks.
87You might want to turn it off if you have clients
88that don't support pre-authentication.
89Since the version 4 protocol doesn't support any pre-authentication,
90serving version 4 clients is just about the same as not requiring
91pre-athentication.
92The default is to require pre-authentication.
93Adding the require-preauth per principal is a more flexible way of
94handling this.
95.It Xo
96.Fl -max-request= Ns Ar size
97.Xc
98Gives an upper limit on the size of the requests that the kdc is
99willing to handle.
100.It Xo
101.Fl H ,
102.Fl -enable-http
103.Xc
104Makes the kdc listen on port 80 and handle requests encapsulated in HTTP.
105.It Xo
106.Fl -no-524
107.Xc
108don't respond to 524 requests
109.It Xo
110.Fl -kerberos4
111.Xc
112respond to Kerberos 4 requests
113.It Xo
114.Fl -kerberos4-cross-realm
115.Xc
116respond to Kerberos 4 requests from foreign realms.
117This is a known security hole and should not be enabled unless you
118understand the consequences and are willing to live with them.
119.It Xo
120.Fl r Ar string ,
121.Fl -v4-realm= Ns Ar string
122.Xc
123What realm this server should act as when dealing with version 4
124requests.
125The database can contain any number of realms, but since the version 4
126protocol doesn't contain a realm for the server, it must be explicitly
127specified.
128The default is whatever is returned by
129.Fn krb_get_lrealm .
130This option is only availabe if the KDC has been compiled with version
1314 support.
132.It Xo
133.Fl K ,
134.Fl -kaserver
135.Xc
136Enable kaserver emulation (in case it's compiled in).
137.It Xo
138.Fl P Ar portspec ,
139.Fl -ports= Ns Ar portspec
140.Xc
141Specifies the set of ports the KDC should listen on.
142It is given as a
143white-space separated list of services or port numbers.
144.It Fl -addresses= Ns Ar list of addresses
145The list of addresses to listen for requests on.
146By default, the kdc will listen on all the locally configured
147addresses.
148If only a subset is desired, or the automatic detection fails, this
149option might be used.
150.El
151.Pp
152All activities are logged to one or more destinations, see
153.Xr krb5.conf 5 ,
154and
155.Xr krb5_openlog 3 .
156The entity used for logging is
157.Nm kdc .
158.Sh CONFIGURATION FILE
159The configuration file has the same syntax as
160.Xr krb5.conf 5 ,
161but will be read before
162.Pa /etc/krb5.conf ,
163so it may override settings found there.
164Options specific to the KDC only are found in the
165.Dq [kdc]
166section.
167All the command-line options can preferably be added in the
168configuration file.
169The only difference is the pre-authentication flag, which has to be
170specified as:
171.Pp
172.Dl require-preauth = no
173.Pp
174(in fact you can specify the option as
175.Fl -require-preauth=no ) .
176.Pp
177And there are some configuration options which do not have
178command-line equivalents:
179.Bl -tag -width "xxx" -offset indent
180.It Li check-ticket-addresses = Va boolean
181Check the addresses in the ticket when processing TGS requests.
182The default is FALSE.
183.It Li allow-null-ticket-addresses = Va boolean
184Permit tickets with no addresses.
185This option is only relevant when check-ticket-addresses is TRUE.
186.It Li allow-anonymous = Va boolean
187Permit anonymous tickets with no addresses.
188.It encode_as_rep_as_tgs_rep = Va boolean
189Encode AS-Rep as TGS-Rep to be bug-compatible with old DCE code.
190The Heimdal clients allow both.
191.It kdc_warn_pwexpire = Va time
192How long before password/principal expiration the KDC should start
193sending out warning messages.
194.El
195.Pp
196The configuration file is only read when the
197.Nm
198is started.
199If changes made to the configuration file are to take effect, the
200.Nm
201needs to be restarted.
202.Pp
203An example of a config file:
204.Bd -literal -offset indent
205[kdc]
206 require-preauth = no
207 v4-realm = FOO.SE
208 key-file = /key-file
209.Ed
210.Sh BUGS
211If the machine running the KDC has new addresses added to it, the KDC
212will have to be restarted to listen to them.
213The reason it doesn't just listen to wildcarded (like INADDR_ANY)
214addresses, is that the replies has to come from the same address they
215were sent to, and most OS:es doesn't pass this information to the
216application.
217If your normal mode of operation require that you add and remove
218addresses, the best option is probably to listen to a wildcarded TCP
219socket, and make sure your clients use TCP to connect.
220For instance, this will listen to IPv4 TCP port 88 only:
221.Bd -literal -offset indent
222kdc --addresses=0.0.0.0 --ports="88/tcp"
223.Ed
224.Pp
225There should be a way to specify protocol, port, and address triplets,
226not just addresses and protocol, port tuples.
227.Sh SEE ALSO
228.Xr kinit 1 ,
229.Xr krb5.conf 5
2.\" (Royal Institute of Technology, Stockholm, Sweden).
3.\" All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\"
9.\" 1. Redistributions of source code must retain the above copyright
10.\" notice, this list of conditions and the following disclaimer.
11.\"
12.\" 2. Redistributions in binary form must reproduce the above copyright
13.\" notice, this list of conditions and the following disclaimer in the
14.\" documentation and/or other materials provided with the distribution.
15.\"
16.\" 3. Neither the name of the Institute nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\" $Id: kdc.8,v 1.23 2003/04/06 17:48:40 lha Exp $
33.\"
34.Dd August 22, 2002
35.Dt KDC 8
36.Os HEIMDAL
37.Sh NAME
38.Nm kdc
39.Nd Kerberos 5 server
40.Sh SYNOPSIS
41.Nm
42.Oo Fl c Ar file \*(Ba Xo
43.Fl -config-file= Ns Ar file
44.Xc
45.Oc
46.Op Fl p | Fl -no-require-preauth
47.Op Fl -max-request= Ns Ar size
48.Op Fl H | Fl -enable-http
49.Op Fl -no-524
50.Op Fl -kerberos4
51.Op Fl -kerberos4-cross-realm
52.Oo Fl r Ar string \*(Ba Xo
53.Fl -v4-realm= Ns Ar string
54.Xc
55.Oc
56.Op Fl K | Fl -kaserver
57.Oo Fl P Ar portspec \*(Ba Xo
58.Fl -ports= Ns Ar portspec
59.Xc
60.Oc
61.Op Fl -detach
62.Op Fl -addresses= Ns Ar list of addresses
63.Sh DESCRIPTION
64.Nm
65serves requests for tickets.
66When it starts, it first checks the flags passed, any options that are
67not specified with a command line flag are taken from a config file,
68or from a default compiled-in value.
69.Pp
70Options supported:
71.Bl -tag -width Ds
72.It Xo
73.Fl c Ar file ,
74.Fl -config-file= Ns Ar file
75.Xc
76Specifies the location of the config file, the default is
77.Pa /var/heimdal/kdc.conf .
78This is the only value that can't be specified in the config file.
79.It Xo
80.Fl p ,
81.Fl -no-require-preauth
82.Xc
83Turn off the requirement for pre-autentication in the initial AS-REQ
84for all principals.
85The use of pre-authentication makes it more difficult to do offline
86password attacks.
87You might want to turn it off if you have clients
88that don't support pre-authentication.
89Since the version 4 protocol doesn't support any pre-authentication,
90serving version 4 clients is just about the same as not requiring
91pre-athentication.
92The default is to require pre-authentication.
93Adding the require-preauth per principal is a more flexible way of
94handling this.
95.It Xo
96.Fl -max-request= Ns Ar size
97.Xc
98Gives an upper limit on the size of the requests that the kdc is
99willing to handle.
100.It Xo
101.Fl H ,
102.Fl -enable-http
103.Xc
104Makes the kdc listen on port 80 and handle requests encapsulated in HTTP.
105.It Xo
106.Fl -no-524
107.Xc
108don't respond to 524 requests
109.It Xo
110.Fl -kerberos4
111.Xc
112respond to Kerberos 4 requests
113.It Xo
114.Fl -kerberos4-cross-realm
115.Xc
116respond to Kerberos 4 requests from foreign realms.
117This is a known security hole and should not be enabled unless you
118understand the consequences and are willing to live with them.
119.It Xo
120.Fl r Ar string ,
121.Fl -v4-realm= Ns Ar string
122.Xc
123What realm this server should act as when dealing with version 4
124requests.
125The database can contain any number of realms, but since the version 4
126protocol doesn't contain a realm for the server, it must be explicitly
127specified.
128The default is whatever is returned by
129.Fn krb_get_lrealm .
130This option is only availabe if the KDC has been compiled with version
1314 support.
132.It Xo
133.Fl K ,
134.Fl -kaserver
135.Xc
136Enable kaserver emulation (in case it's compiled in).
137.It Xo
138.Fl P Ar portspec ,
139.Fl -ports= Ns Ar portspec
140.Xc
141Specifies the set of ports the KDC should listen on.
142It is given as a
143white-space separated list of services or port numbers.
144.It Fl -addresses= Ns Ar list of addresses
145The list of addresses to listen for requests on.
146By default, the kdc will listen on all the locally configured
147addresses.
148If only a subset is desired, or the automatic detection fails, this
149option might be used.
150.El
151.Pp
152All activities are logged to one or more destinations, see
153.Xr krb5.conf 5 ,
154and
155.Xr krb5_openlog 3 .
156The entity used for logging is
157.Nm kdc .
158.Sh CONFIGURATION FILE
159The configuration file has the same syntax as
160.Xr krb5.conf 5 ,
161but will be read before
162.Pa /etc/krb5.conf ,
163so it may override settings found there.
164Options specific to the KDC only are found in the
165.Dq [kdc]
166section.
167All the command-line options can preferably be added in the
168configuration file.
169The only difference is the pre-authentication flag, which has to be
170specified as:
171.Pp
172.Dl require-preauth = no
173.Pp
174(in fact you can specify the option as
175.Fl -require-preauth=no ) .
176.Pp
177And there are some configuration options which do not have
178command-line equivalents:
179.Bl -tag -width "xxx" -offset indent
180.It Li check-ticket-addresses = Va boolean
181Check the addresses in the ticket when processing TGS requests.
182The default is FALSE.
183.It Li allow-null-ticket-addresses = Va boolean
184Permit tickets with no addresses.
185This option is only relevant when check-ticket-addresses is TRUE.
186.It Li allow-anonymous = Va boolean
187Permit anonymous tickets with no addresses.
188.It encode_as_rep_as_tgs_rep = Va boolean
189Encode AS-Rep as TGS-Rep to be bug-compatible with old DCE code.
190The Heimdal clients allow both.
191.It kdc_warn_pwexpire = Va time
192How long before password/principal expiration the KDC should start
193sending out warning messages.
194.El
195.Pp
196The configuration file is only read when the
197.Nm
198is started.
199If changes made to the configuration file are to take effect, the
200.Nm
201needs to be restarted.
202.Pp
203An example of a config file:
204.Bd -literal -offset indent
205[kdc]
206 require-preauth = no
207 v4-realm = FOO.SE
208 key-file = /key-file
209.Ed
210.Sh BUGS
211If the machine running the KDC has new addresses added to it, the KDC
212will have to be restarted to listen to them.
213The reason it doesn't just listen to wildcarded (like INADDR_ANY)
214addresses, is that the replies has to come from the same address they
215were sent to, and most OS:es doesn't pass this information to the
216application.
217If your normal mode of operation require that you add and remove
218addresses, the best option is probably to listen to a wildcarded TCP
219socket, and make sure your clients use TCP to connect.
220For instance, this will listen to IPv4 TCP port 88 only:
221.Bd -literal -offset indent
222kdc --addresses=0.0.0.0 --ports="88/tcp"
223.Ed
224.Pp
225There should be a way to specify protocol, port, and address triplets,
226not just addresses and protocol, port tuples.
227.Sh SEE ALSO
228.Xr kinit 1 ,
229.Xr krb5.conf 5