source: postlfs/security/heimdal/heimdal-config.xml@ 34598ae

<sect2>
<title>Configuring Heimdal</title>

<sect3><title>Config files</title>
<para><filename>/etc/heimdal/*</filename></para>
</sect3>

<sect3><title>Configuration Information</title>

<sect4><title>Master KDC Server Configuration</title>

<para>
Create the Kerberos configuration file with the following command:
</para>

<screen><userinput><command>install -d /etc/heimdal &amp;&amp;
cat &gt; /etc/heimdal/krb5.conf &lt;&lt; "EOF"</command>
# Begin /etc/heimdal/krb5.conf
        
[libdefaults]
    default_realm = <replaceable>[LFS.ORG]</replaceable>
    encrypt = true

[realms]
    <replaceable>[LFS.ORG]</replaceable> = {
        kdc = <replaceable>[belgarath.lfs.org]</replaceable>
        admin_server = <replaceable>[belgarath.lfs.org]</replaceable>
        kpasswd_server = <replaceable>[belgarath.lfs.org]</replaceable>
    }

[domain_realm]
    .<replaceable>[lfs.org]</replaceable> = <replaceable>[LFS.ORG]</replaceable>

[logging]
    kdc = FILE:/var/log/kdc.log
    admin_server = FILE:/var/log/kadmin.log
    default = FILE:/var/log/krb.log

# End /etc/heimdal/krb5.conf
<command>EOF</command></userinput></screen>

<para>
You will need to substitute your domain and proper hostname for the
occurances of the belgarath and lfs.org names.
</para>

<para>
<userinput>default_realm</userinput> should be the name of your domain changed to ALL CAPS.
This isn't required, but both Heimdal and <acronym>MIT</acronym>
recommend it.
</para>

<para>
<userinput>encrypt = true</userinput> provides encryption of all traffic between kerberized
clients and servers. It's not necessary and can be left off. If you
leave it off, you can encrypt all traffic from the client to the server
using a switch on the client program instead.
</para>

<para>
The <userinput>[realms]</userinput> parameters tell the client programs where to look for the
<acronym>KDC</acronym> authentication services.
</para>

<para>
The <userinput>[domain_realm]</userinput> section maps a domain to a realm.
</para>

<para>
Store the master password in a key file using the following commands:
</para>

<screen><userinput><command>install -d -m 755 /var/lib/heimdal &amp;&amp;
kstash</command></userinput></screen>

<para>
Create the <acronym>KDC</acronym> database:
</para>

<screen><userinput><command>kadmin -l</command></userinput></screen>

<para>
Choose the defaults for now. You can go in later and change the
defaults, should you feel the need. At the
<userinput>kadmin&gt;</userinput> prompt, issue the following statement:
</para>

<screen><userinput><command>init <replaceable>[LFS.ORG]</replaceable></command></userinput></screen>

<para>
Now we need to populate the database with principles (users). For now,
just use your regular login name or root. 
</para>

<screen><userinput><command>add <replaceable>[loginname]</replaceable></command></userinput></screen>

<para>
The <acronym>KDC</acronym> server and any machine running kerberized
server daemons must have a host key installed:
</para>

<screen><userinput><command>add --random-key host/<replaceable>[belgarath.lfs.org]</replaceable></command></userinput></screen>

<para>
After choosing the defaults when prompted, you will have to export the
data to a keytab file:
</para>

<screen><userinput><command>ext host/<replaceable>[belgarath.lfs.org]</replaceable></command></userinput></screen>

<para>
This should have created two files in
<filename class="directory">/etc/heimdal</filename>;
<filename>krb5.keytab</filename> (Kerberos 5) and
<filename>srvtab</filename> (Kerberos 4). Both files should have 600
(root rw only) permissions. Keeping the keytab files from public access
is crucial to the overall security of the Kerberos installation.
</para>

<para>
Eventually, you'll want to add server daemon principles to the database
and extract them to the keytab file. You do this in the same way you
created the host principles. Below is an example:
</para>

<screen><userinput><command>add --random-key ftp/<replaceable>[belgarath.lfs.org]</replaceable></command></userinput></screen>

<para>
(choose the defaults)
</para>

<screen><userinput><command>ext ftp/<replaceable>[belgarath.lfs.org]</replaceable></command></userinput></screen>

<para>
Exit the <command>kadmin</command> program (use <command>quit</command>
or <command>exit</command>) and return back to the shell prompt. Start
the <acronym>KDC</acronym> daemon manually, just to test out the 
installation:
</para>

<screen><userinput><command>/usr/sbin/kdc &amp;</command></userinput></screen>

<para>
Attempt to get a <acronym>TGT</acronym> (ticket granting ticket) with the 
following command:
</para>

<screen><userinput><command>kinit <replaceable>[loginname]</replaceable></command></userinput></screen>

<para>
You will be prompted for the password you created. After you get your
ticket, you should list it with the following command:
</para>

<screen><userinput><command>klist</command></userinput></screen>

<para>
Information about the ticket should be displayed on the screen.
</para>

<para>
To test the functionality of the keytab file, issue the following
command:
</para>

<screen><userinput><command>ktutil list</command></userinput></screen>

<para>
This should dump a list of the host principals, along with the encryption
methods used to access the principals.
</para>

<para>
At this point, if everything has been successful so far, you can feel
fairly confident in the installation and configuration of the package.
</para>

<para>Install <filename>/etc/rc.d/init.d/heimdal</filename> init script
included in the <xref linkend="intro-important-bootscripts"/>
package.</para>

<screen><userinput><command>make install-heimdal</command></userinput></screen>

</sect4>

<sect4><title>Using Kerberized Client Programs</title>

<para>
To use the kerberized client programs (<command>telnet</command>,
<command>ftp</command>, <command>rsh</command>,
<command>rxterm</command>, <command>rxtelnet</command>,
<command>rcp</command>, <command>xnlock</command>), you first must get
a <acronym>TGT</acronym>. Use the <command>kinit</command> program to
get the ticket. After you've acquired the ticket, you can use the
kerberized programs to connect to any kerberized server on the network.
You will not be prompted for authentication until your ticket expires
(default is one day), unless you specify a different user as a command
line argument to the program.
</para>

<para>
The kerberized programs will connect to non kerberized daemons, warning
you that authentication is not encrypted. As mentioned earlier, only the
<command>ftp</command> program gives any trouble connecting to non
kerberized daemons.
</para>

<para>
For additional information consult <ulink
url="http://www.linuxfromscratch.org/hints/downloads/files/heimdal.txt">the
Heimdal hint</ulink> on which the above instructions are based.
</para>

</sect4>

</sect3>

</sect2>