Kerberos authentication without reverse lookup

Roland Dowdeswell elric at imrryr.org
Tue Jan 18 18:45:58 EST 2005


On 1106079270 seconds since the Beginning of the UNIX epoch
Fredrik Tolf wrote:
>

>I came up with a fairly simple solution that would be  to add, to inetd
>on each host, a simple program that just echoes to the connecting host
>what that host's perception of its own FQDN is. Then I'd write a simple
>nsswitch module for gethostbyaddr (possibly with some kind of config
>file so that it never tries for hosts that aren't supposed to be part of
>this) that connects to this service on the address that it is supposed
>to canonicalize.

You could always do what Heimdal does which is use ai->ai_canonname
rather than performing a reverse lookup.  Unfortunately, this strategy
is not followed by 3rd party vendors such as OpenSSH.

You stated in a prior e-mail that you were using IPv6.  In this
case there is no need to write an inetd service, it would be better
to just use ICMP6 a la ``ping -w host''---at least with IPv6 asking
a host for its name is an implemented standard.

--
    Roland Dowdeswell                      http://www.Imrryr.ORG/~elric/


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