[gentoo-user] Gentoo speaking to Android

Hi,

my setup is a recent Gentoo system, which is connected to the
internet. This acts as an Wifi hotspot for my android tablet.

I wiresharked some connections of this tablet to the internet
and it was -- lets say -- "astonished", how much this little 
tablet has to tell people, which I dont know and have never heard
of only by astablishing the connection and doing nothing else.

Since rooting an android device is common for nerds and geeks
only most firewalls available for android devices are so called
"no root firewalls" which tunnel all traffic through a local
VPN. These come also whith an understandable GUI.

My problem is, that these totally block traffic which is
initiated from outside the android device (which is a
good idea regarding firewalls).

I sideload all my programs (no contact to google
services for privacy reasons) by starting a webserver on
my tablet and send the data from my PC to the tablet --
which is now impossible because I am using a firewall.

My question is:
I only want to allow my tablet to connect via wifi
to my PC (I am using the "create_ap" script).
Due the firewall I need to fetch the data from
my PC instead of sending the data to my tablet.
It is sufficient to get access to only one directory
of my PC.
I dont want to setup a complete webserver on my PC
just for some Megs of data to transfer.

What is a secure, easy to setup and convenient method
to acchieve this?
(I only need some keywords ... no howtos needed. Will
try to setup the rest mysefl...;)

Thank you very much in advance for any help!

Best regards,
Meino