second(?) cut at (user space) 802.1x supplicant program.

first of all, I'm becoming slightly more proud of the code --
this is work in progress, the third(?) rough version that works.
it still needs cleaning up.

However, we have now better integration of the state
machine in a thread(2) programming style program.
we (try to) replace(d) synchronisation via global channels
by the use of channels.
In particular, the whole thing now runs at proper speed,
finishing in about two seconds, instead of the 20-30
seconds we needed earlier, because then, as it turned out,
we would process one packet and send the return in
two seconds.

clean up in particular: creating/parsing of messages,
 debugging output (reduce amount, make more useful),
 more robust message parsing (check all lengths),
 make sure we do the right thing when we 'hang'
 in the tls handshake, and have to clean up because
 in the middle of the tls handshake we receive a new
 Identity request - tlsClient may hang in readN)
 fix the timers such that reset gets rid of one that
 hangs in sleep, fix memory leak (certificate? sessionID?).
I hope this will happen in due time.

I'm making this available to allow constructive criticism.


This depends on:
 - the tlshand patches I submitted on sources/patch
    and which have been applied in the mean time
 - fastkey support in wlan driver
     (separate wavelan.[ch] etherwavelan.c)

It assumes a writable, append-only /sys/log/8021x file.
to which it writes _a_lot_ of debugging.

command line option -d outputs lots of debugging
command line option -D outputs tls handshake debugging

there are command line options to pass thumbprint directory,
and use the thumbprints to check certificate, but this
has never been tried.

we do not need to worry about TLS session resumption,
after the rewrite of the state machines + threadmain
the whole auth+keysetting now takes approx. 2 seconds
to complete (instead of the earlier 15 sec only needed
by tlsClient


TODO:
 - code cleanup
 - see if we can fix (one again) the memory leak (leaking 32K per re-auth?)
 - see  why we sometimes get error
        'invalid initial SSL2-like message' - most likely this is
     because we do incorrect cleanup/resumption after a
     first fail.
 - test server certificate checking 
 - reduce (debug) output to syslog
 - make the whole thing a file server?
    with e.g.
     - a ctl file for control messages (what kind of?)
     - a stats file for statistics (e.g. numbers suggested in 802.1x standard)
     - a log file, to which logging will be written if/when opened
     - a tlslog file, to which the tls handshake trace will be written,
        if/when opened
     - others?

Axel.Belinfante@cs.utwente.nl