[nos-bbs] Telnet forwarding with JNOS

[Maiko Langelaar]

Greetings all,

I've heard people complain about this from time to time, but nobody has
ever really pressed this issue on me, so it never got alot of attention.

Several years ago it came up, the solution was simply to not use telnet
forwarding and setup an AXIP or AXUDP interface instead. I actually took
a look at the code a few years ago, and here is my technical assessment
of why telnet forwarding with JNOS is *inconsistent* - please read it :

The receive process of any telnet connection to JNOS looks for what is
called the Interpret As Command (IAC) Character, which incidently is the
value 255 (0xff). If JNOS sees the IAC in any telnet connection, it will
insert an extra 2 bytes of control characters type of thing.

Now that Michael has brought this up once again, perhaps it's time to
just force the telnet stream to switch off telnet options (as is done
for any AX25 or NETROM streams). If you look at the code in mboxgate.c,
look for the gw_input () function around line number 266, and you will
see a bit further down a 'int no_tel_opts = 0'.

I'm going to create an option in a subsequent release, but in the mean
time (Michael this is for you), edit your code, change the 0 to 1, then
try your telnet forward. I'm sure it will work fine !

This usually just happens with compressed (FBB) modes, chances of a 0xff
character are very high when using any compress forwarding. The chances of
this happening for ascii forwarding are next to none, unless someone some
how inserted a next ascii character in the mail message (using a editor),
and buy some fluke it got in there.

So why didn't I fix it back then ? Well, some people thought my IAC theory
was out to lunch, and the conversation kinda fell off the radar scope, and
I just told myself, okay let the 'know it alls' have their way :)

Have a great day :)

Maiko