rudimentary preauth working

[Simon Josefsson]

FYI, I succeeded getting basic preauth to work.  The code is ugly, and
you'll have to enter the password twice (once to generate the preauth
and once to decrypt the AS-REP), and it doesn't handle non-default
salts, but seem to work against MIT KDC.

I should clean this up, so it automatically send a preauth AS-REQ when
it receive the KRB-ERROR response that indicate this problem, and only
query for a password once.

Note that you'll need to use -o preauth, or put 'preauth' in the
configuration file.  This is undocumented for now, because I don't
think it should be required in the final release.

Try tomorrow's nightly build, if you don't build from CVS.

If it doesn't work, please run with 'shishi -v -v -v -v -o preauth
foo' and send the output (which will contain the password, so use a
dummy account).

More later this week, first I should get gnutls 1.4.0 released...

/Simon

address@hidden:~/src/shishi$ src/shishi -d
1 ticket removed.
address@hidden:~/src/shishi$ src/shishi jas2
Error code from server:
Additional pre-authentication required
Additional error message from server:
NEEDED_PREAUTH
Types of PA-DATA requested: 2, 11, 19, 13.
Preauth required, try `-o preauth'.
/home/jas/src/shishi/src/.libs/lt-shishi: Could not get ticket as `jas2' for 
`krbtgt/JOSEFSSON.ORG'.
address@hidden:~/src/shishi$ src/shishi -o preauth jas2
Enter password for address@hidden':

Enter password for address@hidden':

address@hidden:
Authtime:       Wed Apr 19 18:06:15 2006
Endtime:        Thu Apr 20 02:06:14 2006
Server:         krbtgt/JOSEFSSON.ORG key des3-cbc-sha1-kd (16)
Ticket key:     des3-cbc-sha1-kd (16) protected by des3-cbc-sha1-kd (16)
Ticket flags:   INITIAL PREAUTHENT (1536)
address@hidden:~/src/shishi$