Description
INTRODUCTION
The Internet Of Things is populated with an ever expanding range of sensors and
appliances. Initially such devices were likely to be connected to monitoring and
control devices over purely local/personal networks (e.g. infra-red, Bluetooth,
ZigBee), but it is increasingly common to connect such devices (directly or via a
bridge) to the internet. This enables remote monitoring and control, but it also
exposes them to a variety of remote attacks.
For some targets (e.g. a national power grid or Uranium separation centrifuges)
their stratigic importance and need for protection should be clear. It might not be
immediatly obvious how one might hijack simple devices (e.g. light switches or
temperature/humidity sensors) for nefarious purposes, but:
there have been numerous instances where web-cams, have been hijacked to
violate peoples’ privacy.
smart devices like routers, baby-monitors, washing machines, and even
lightbulbs have been conscripted into bot-nets to mount Distributed Denial of
Service attacks.
security researchers have been able to hijack the digital controls of recent
cars.
consider the havoc that could be wrought by someone who was able to seize
control of a networked pace-maker or insulin pump.
Prudence suggests that all communications and control for IOT devices should be
encrypted.
In this project we will extend your embedded temperature sensor to accept
commands from, and send reports back to a network server. You will do this over
both unencrypted and encrypted channels.
RELATION TO READING AND LECTURES
This project applies the principles discussed in the reading and lectures on
Cryptography, Distributed Systems Security, and Secure Socket Layer encryption.
PROJECT OBJECTIVES
Primary: Demonstrate the ability to design, build and debug an embedded
application that interacts with a central control server with the aid of serverside logs.
Primary: Demonstrate the ability to implement a secure channel using
standard tools.
Primary: Demonstrate the ability to research and exploit a complex API, and to
debug an application involving encrypted communication.
DELIVERABLES
A single compressed tarball (.tar.gz) containing:
C source files for two embedded applications (lab4c_tcp and lab4c_tls) that
build and run (with no errors or warnings) on an Edison.
A Makefile to build and test your application. The higher level targets should
include:
default … build both versions your program
clean … delete all programs and output created by the Makefile
dist … create the deliverable tarball
Note that this Makefile is intended to be executed on an Edison, but you may
find it convenient to create a Makefile that can be run on either an Edison or a
Linux server/desktop/notebook.
a README file containing:
descriptions of each of the included files and any other information about
your submission that you would like to bring to our attention (e.g.
research, limitations, features, testing methodology).
any other comments on your submission (e.g. references consulted, slip
days, etc.)
PREPARATION
Part 1
Obtain the host name, port # and server status URL for the TCP logging
server.
Part 2
Obtain the host name, port # and server status URL for the TLS logging
server.
Review the documentation for the OpenSSL SSL/TLS library, which should
already be installed on your Edison. You will likely want to seek out
additional tutorials on using OpenSSL to initiate connections and verify
server certificates.
PROJECT DESCRIPTION
Part 1: Communication with a Logging Server
Write a program (called lab4c_tcp) that:
builds and runs on your Edison
is based on the temperature sensor application you built previously
accepts the following parameters:
–id=9-digit-number
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–host=name or address
–log=filename
(required) port number
Note: that there is no –port= in front of the port number. This is non-switch
parameter.
It accepts the same commands and generates the same reports as the
previous Edison project, but now the input and output are from/to a network
connection to a server.
open a TCP connection to the server at the specified address and port
immediately send (and log) an ID terminated with a newline:
ID=ID-number. This new report enables the server to keep track of which
devices it has received reports from.
send (and log) newline terminated temperature reports over the
connection
process (newline terminated) commands reveived over the connection
the last command sent by the server will (as before) be OFF
as before, assume that the temperature sensor has been connected to Analog
input 0.
The ID number will appear in the TCP server log (follow the TCP server URL), and
will permit you to find the reports for your sessions. To protect your privacy, You
do not have to use your student ID number, but merely a nine-digit number that
you will recognize and that will be different from the numbers chosen by others.
From the server status page, you will also be able to see, for each client, a log of
all commands sent to and reports received from that client in the most recent
session.
To facilitate development and testing I wrote my program to, if compiled with a
special (-DDUMMY) define, include mock implementations for
the mraa_aio_ functionality, enabling me to do most of my testing on my desktop. I
then modified my Makefile run the command “uname -r”, check for the presence
of the string “edison” in that output, and if not found, build with a rule that passed
the -DDUMMY flag to gcc.
Part 2: Authenticated TLS Session Encryption
Write a program (called lab4c_tls) that:
builds and runs on your Edison
is based on the remote logging appliance build in part 1
operates by:
opening a TLS connection to the server at the specified address and port.
sending your student ID followed by a newline
send temperature reports over the connection
process commands reveived over the connection
the last command sent by the server will be OFF
The ID number will appear in the TLS server log (follow the TLS server URL), and
will permit you to find the reports for your sessions.
Note that you may choose to:
write two versions of the program
write a single program that can be compiled to produce two different
executables
write a single executable that implements both functionalities, and chooses
which based on the name by which it was invoked. In this last case, your
Makefile should produce two different links (with the required names) to that
program.
SUMMARY OF EXIT CODES
0: successful run
1: invalid command-line parameters (e.g. unrecognized parameter, no such host)
2: other run-time failures
SUBMISSION
Your tarball should have a name of the form lab4c-studentID.tar.gz. You can sanity
check your submission with this test script which should run on your Edison or (if
with appropriately dummied sensor access) on your usual Linux development
environment.
Note that the sanity checker works, in part, by checking the server logs for entries
corresponding to the student ID you have given as a parameter. Thus, in order to
pass the sanity check, you must have had recent successful sessions using your
own student ID number (or at least the same number you have used to name your
submission tarball).
