Faking POP

As part of a networking class at my lab we teach students protocols by asking them to implement a simple POP3 client in Java. The client must connect to the POP3 server and interact with the server as a normal POP client.

As soon as the class started we realized the university POP server uses SSL to encrypt the connection (for obvious security reasons) and asking the students to implement the SSL part of the client was not an option.

We needed a POP server set up quickly before the students could present their programs or at least something that behaves like a POP server. A quick search resulted in FakePOP and the great Ubuntu has it in their repositories.

I simply issued the following command:

sudo aptitude install xinetd fakepop

Then create a xinetd configuration file "/etc/xinet.d/fakepop" that contains the following:

service pop3
{
server = /usr/sbin/in.fakepop
disable = no
socket_type = stream
protocol = tcp
user = nobody
wait = no
}

and restart the xinetd daemon:

sudo /etc/init.d/xinetd restart

and in less than a minute I had a POP3 server (or at least something that behaves like one) on my machine and the class was saved.

Also you can create a custom message to be delivered to anyone connecting to the fakepop server. You can create as many messages as you want by putting them as text files inside the "/etc/fakepop" directory. Some examples can be found in the "/usr/share/doc/fakepop/examples" directory like the one below:

From: System Administrator
Subject: example message - text only
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline

This is a simple message.
It contains only text.