language; say something about kadmin del_enctype

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@8639 ec53bebd-3082-4978-b11e-865c3cabbd6b
This commit is contained in:
Johan Danielsson
2000-07-10 11:50:05 +00:00
parent 66889b64d7
commit beb57945e8

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@@ -4,11 +4,11 @@
@section Making things work on Ciscos
Modern versions of Cisco IOS has some support for authenticating via
Kerberos 5. This can be used both to verify passwords via a ticket
exchange Kerberos 5 (boring), and to use Kerberos authenticated telnet
to access your router (less boring). The following has been tested on
IOS 11.2(12), things might be different with other versions. Old
versions are known to have bugs.
Kerberos 5. This can be used both by having the router get a ticket when
you login (boring), and by using Kerberos authenticated telnet to access
your router (less boring). The following has been tested on IOS
11.2(12), things might be different with other versions. Old versions
are known to have bugs.
To make this work, you will first have to configure your router to use
Kerberos (this is explained in the documentation). A sample
@@ -24,31 +24,25 @@ kerberos server FOO.SE 10.0.0.1
kerberos instance map admin 15
@end example
This tells you (among other things) that the when logging in, the router
should try to authenticate with kerberized telnet, and if that fails try
This tells you (among other things) that when logging in, the router
should try to authenticate with kerberised telnet, and if that fails try
to verify a plain text password via a Kerberos ticket exchange (as
opposed to a local database or RADIUS or something similar), and if that
opposed to a local database, RADIUS or something similar), and if that
fails try the local enable password. If you're not careful when you
specify the `login default' authentication mechanism, you might not be
able to login. The `instance map' and `authorization exec' lines says
that people with `admin' instances should be given `enabled' shells when
logging in.
able to login at all. The `instance map' and `authorization exec' lines
says that people with `admin' instances should be given `enabled' shells
when logging in.
The numbers after the principal on the `srvtab' line are principal type,
timestamp (in seconds since 1970), key version number (4), keytype (1 ==
des), key length (always 8 with des), and then the key.
To make the Heimdal KDC produce tickets that the Cisco can decode you
might have to turn on the @samp{encode_as_rep_as_tgs_rep} flag in the
KDC. You will also have to specify that the router can't handle anything
but @samp{des-cbc-crc}. There currently isn't an easy way to do
this. The best you can do is to dump your database (with @samp{kadmin -l
dump}), remove all entries for keys other than @samp{des-cbc-crc}, and
then reloading the database (@samp{kadmin -l load}). An example should
clarify this. You should have something like (again, truncated):
@example
host/router.foo.se@@FOO.SE 4:0:1:...:-:... - - - - - - - 126
@end example
Change this to:
@example
host/router.foo.se@@FOO.SE 4:0:1:...:- - - - - - - - 126
@end example
but @samp{des-cbc-crc}. This can be done with the @samp{del_enctype}
command of @samp{kadmin}.
This all fine and so, but unless you have an IOS version with encryption
(available only in the U.S) it doesn't really solve any problems. Sure