Accessing STMP on port 443 using SSLH

by Martin Monperrus

In order to use my Thunderbird everywhere, I want to access a SMTP server on HTTPS port 443, which is open in many networks and proxy.

The solution I use sslh, an applicative protocol multiplexer.

The idea is that the SSL traffic to myserver.com goes to an SSL-encrypted SMTP server and the SSH traffic goes to the SSH server.

This is done as follows:

DAEMON_OPTS="--user sslh --listen 0.0.0.0:443 --ssh 127.0.0.1:22 --ssl mysmtpserver:465 --pidfile /var/run/sslh/sslh.pid"

Troubleshooting

To test the connection to the SMTP server:

$ openssl s_client -connect myserver.com:443
220 mysmtpserver You connect to mail606 ESMTP

To connect to the SSH server:

$ ssh -p 443 user@myserver.com

I also imagined to write a SSLH probe for STMP traffic, but this does not seem to be at the level of configuration files

Tagged as: