Hi Jochen,
You are correct, I do not want to manipulate a TCP/IP packet.  I do want to add to the application level HTTP packet.  That should be ok as long as I am careful, I think.  Maybe I should say that I want to add to the HTTP request, and leave it at that.

Yes, there is a reason.  stunnel *contains* the data I want to communicate from client stunnel to server stunnel, within an HTTP request.

I sense a real appreciation out there for how well stunnel does it's job, and within that a warning not to disturb it.  I surely understand that.  stunnel is a means to an end for me.  I am not looking to extend it's capabilities in any way that would be incorporated into the code base.

Regards.


On Wed, Mar 26, 2014 at 8:36 AM, Jochen Bern <Jochen.Bern@linworks.de> wrote:
On 26.03.2014 13:05, Michael Carlino (RIT Student) wrote:
> In the client stunnel I need to make a small change to the HTTP
> packet.  I need to add some data to it.

Then you *don't* want to manipulate *packets* (as in, using iptables,
tcpdump, wireshark etc.). Adding data to a packet will mess up basic
TCP/IP mechanisms like path MTU discovery real fierce.

> I know that as a proxy stunnel has to be and tries to be general in
> nature.  I am not concerned (right now) with developing a feature that will
> become available to others later.  I don't mind if my changes make my
> development version of stunnel single-purpose.  My work is academic and
> proof-of-concept in it's nature.

Is there a reason - apart from the "server-side stunnel might want to
close the connection" you mentioned - not to leave stunnel to do what it
strives to do, and insert one or two additional layers with some
dedicated HTTP-munging software (say, privoxy) instead? Or, for that
matter, a dedicated SSL sniffer (say, ssldump) if the server side needs
only *read* access to the actual HTTP data?

Regards,
                                                                J. Bern
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