[stunnel-users] A Calypso user needs your help with stunnel

Ludolf Holzheid lholzheid at bihl-wiedemann.de
Tue Sep 2 10:17:24 CEST 2008

On Mon, 2008-09-01 16:25:15 -0700, John Bryant wrote:
> Dear folks:
> I am trying to install stunnel so that I can have an SSL capability with Calypso.
> [..]
> So what do I do now?

Just use the current stunnel version, following the instructions from
stunnel.org (as far as the secure tunnel is concerned, for the
configuration of Calypso, you might follow your HOWTO).

The error messages you get with the older stunnel binary might
indicate a version mismatch of executable (*.exe) and libraries

As the configuration file stuff seems to sound Greek for you:

Stunnel sets up a secure tunnel by acting as a client and a server for
a connection, both at the same time. In the configuration file, you
have to specify the address of the real server ('connect=...', where
the client part of stunnel is supposed to connect to) and the address
where the server part of stunnel is supposed to accept connections
from the real client (Calypso in your case, the 'accept=...' line).

The configuration of the client has to be changed so that it connects
to the server part of stunnel instead of the real server, so the
server address in the client configuration must match the 'accept'
line in the stunnel configuration. The port numbers (right of the
colons) don't really matter, but they have to be unique for each
secure tunnel endpoint on your box.

As mail clients usually use different protocols for sending (SMTP) and
receiving (POP3), two such tunnels have to be configured in the
stunnel configuration file, each in its own section (preceded with a
label in square brackets).

Also, there are some global options in stunnel.conf, such as
'client=...', which determines whether the stunnel runs on the client
box or the server box (i.e. whether the connections from the client
are expected to be already encrypted or not).




Ludolf Holzheid             Tel:    +49 621 339960
Bihl+Wiedemann GmbH         Fax:    +49 621 3392239
Floßwörthstraße 41          e-mail: lholzheid at bihl-wiedemann.de
D-68199 Mannheim, Germany

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