Design Project

Introduction

As a joint project Douglas Wall and I are developing an Implant and Controller for the Information Warfare course COSC429. This project will be topic of my COSC427 design project. The project consists of an application which allows nefarious activities to be performed on a target machine from the comfort of a separate machine. These activities could include,

• Keylogging
• Screen Grabbing
• Remote access to a command prompt.
• Stealing files
• Executing code

The project is to be developed for Windows operating systems. It will be coded in C# and is being developed in Visual Studio 2008. We intend to code using Test Driven Development.

Requirements

More specifically, we wish to achieve the following in our project,

Figure 1 : Project Requirements

ID	Requirement	Description
1	Keylogging	Recording and storing the keystrokes of the victim
2	Screen grabbing	Taking one or many screenshots of the victims computer and storing them
3	Remote command prompt	Getting access to the command prompt which will allow browsing of the computer, the deletion and adding of files, running executable code and so on.
4	Multiple implant management	Allowing more than one victim to be managed by one implant.
5	Data analysis	Automated screening of data from keylogging activities to search for interesting information such as passwords.
6	Command line interface	The controller can be used through the command line.
7	Graphical user interface	The controller has an intuitive, tidy GUI.
8	Stealing files	The controller can select a file from the victim and download it to the controller computer.
9	Scalability	One commander could be responsible for a small army of implants.

Opposing Design Forces

In the creation of my design I found that there were competing forces at play that influenced my approach. I have described these below,

On the one hand I made an effort to conform to the Single reponsibility principle (SRP) however at times I found this could be argued to conflict with Keep related data and behavior in one place. An example of this was when I made the decision to remove the responsibility of recieving, processing and outputting of service information away from the service proxy and place it in a data handler class. However, in my view what qualifies as "related" is not well defined. On this basis I chose to stick to SRP and extract out a class. A further benefit of this is discussed in my Future Work section.

I also noticed a conflict between the need for efficiency and scalability in contrast to clear and easy to understand design. As the number of implants to one commander could potentially be very large it is important to have a streamlined design. This made be feel very aware of the large number of objects that could be created at run time! However, I stuck with the maxim Premature optimization and this has allowed me greater freedom to plan out my design. This conflict has yet to resolve itself as the program is still not fully implemented and tested but the decision has been made on how to approach it.

Maxims, Patterns and General Points of Interest

Separation of Concerns within Commander Project

Draft Notes Please Ignore

Deciding between

1) 1 proxy object to 1 connection 2) 1 proxy object to many connections speaking via the factory

1) Advantages

Easy to implement

Disadvantages

Object explosion! Produces an inflexible design harder to add new services

2) Advantages

Easy to add new services due to loose coupling with the connection Great reduction on numbers of objects

Disadvantages

No clear answer as to who now handles data coming out (I chose to split this reponsibility and have one data processing object for each service on the connection. Can only instantiate what I need at the time)

Other Information

BenjaminTaylor Previous Design Work is a page containing my previous musings on my design project. I just did not want to throw it out!