[sslh] IMAP / SMTP forward in SSLH

[Yves Rutschle]

Hi Tomas,

On Mon, Jan 14, 2013 at 11:01:33AM +0100, Tomas Varil wrote:
> Is there any chance to teach SSLH to forward SSL IMAP 993 and SMTP 587, 465
> for gmail over https? Is it at least technically possible?

If you mean a client (e.g. Thunderbird) connecting over SSL
to sslh with sslh forwarding towards gmail:

Thunderbird ------> sslh -------imap/ssl------> imap.gmail.com
                     |
                     +---------SMTP/ssl-------> smtp.gmail.com

Then I'd say no, because sslh won't be able to differentiate
what's within SSL (sslh does not do any crypto).

If an IMAP client is supposed to "speak" first on a new IMAP
connection, it may be possible to put stunnel in front of
sslh so sslh can switch protocols, and then go through
stunnel again to keep a secured connection:

Thunderbird -SSL--> stunnel -----> sslh -imap--> stunnel --imap/ssl--->imap.gmail.com
                                    |
                                    +--smtp--> stunnel ---SMTP/ssl---> smtp.gmail.com

At that stage I'd tend to suggest setting up an ssh server
in stead of sslh and do port forwarding though...


> I would also like to kindly ask to correct my name to
> ,,Added LSB tags to etc.init.d.sslh (Tomas Varil)." on
> http://www.rutschle.net/tech/sslh.shtml.

Indeed, sorry about that.

Y.