Experiments for my project on authenticating a radio uplink to the NUTS cubesat. The final report can be found here.
Assumes you have a Raspbian image installed on a RPi with a WiFi dongle. This setup uses the model B+ RPi with a WiPi dongle.
Install hostapd and configure the RPi as a access point:
$ sudo apt-get install hostapd
Configuration:
$ sudo sh -c 'echo DAEMON_CONF="/etc/hostapd/hostapd.conf" >> /etc/default/hostapd"'
Copy the hostapd.conf from the repo to /etc/hostapd/hostapd.conf, and
restart the service:
$ sudo service hostapd restart
Install dnsmasq to assign IP addresses to peers on the network:
$ sudo apt-get install dnsmasq
$ sudo sh -c "echo -e 'interface=wlan0\ndhcp-range=10.0.0.2,10.0.0.255,255.255.255.0,12h\nlisten-address=10.0.0.1' >> /etc/dnsmasq.conf"
$ sudo service dnsmasq restart
Configure the /etc/network/interfaces for the server:
auto lo
iface lo inet loopback
iface eth0 inet dhcp
allow-hotplug wlan0
auto wlan0
iface wlan0 inet static
address 10.0.0.1
netmask 255.255.255.0
iface default inet dhcp
And similarliy for the client:
auto lo
iface lo inet loopback
iface eth0 inet dhcp
allow-hotplug wlan0
auto wlan0
iface wlan0 inet dhcp
wireless-essid NUTS
iface default inet dhcp
On each of the devices, install the necessary libraries to run the NUTS scheme:
$ sudo apt-get update
$ sudo apt-get install build-essential python-dev python-pip -y
$ sudo pip install pysha3
$ sudo pip install -e .
Transport for the example app (see sat.py and gs.py) uses UDP.
Connection lost between client and server? It might have been the hostapd driver crashing, if you run ifconfig wlan0 on the server and it doesn't report an IP, that's likely the problem. Try to restart the service to bring it back, sudo service hostapd restart, and bring up the connection again on the client, sudo ifup wlan0.