Course 4 – 13 March 2019

adiftene@info.uaic.ro

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From previous courses…

UML Diagrams:◦ Interactions (Sequence, Collaboration)

◦ Behaviour (States, Activities)

◦ Structure (Deployment)

C4 Model

Forward & Reverse Engineering

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Diagrams

UML Diagrams

Use Case Diagrams

Class Diagrams

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Sequence Diagram contents the sequence of actions which occur in the system, each object invocation methods, as well as the order in timein which these invocations take place

A sequence diagram is bi-dimensional◦ On the vertical axis it shows the life of the object

The lifeline of the objects (graphic: dotted line)

The activation period in which an object takes control of execution (graphic rectangle on the lifeline)

◦ The horizontal axis shows the sequence of creation orthe invocations

messages ordered in time (graphic: darts)

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Emphasizes the structural organization of the objects participating in the interaction

It illustrates better complex ramifications, iterations and concurrent behavior

May contain:◦ Objects, classes, actors

◦ Links between them

◦ Messaging

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State Diagrams, Activity Diagrams

Basic elements

◦ Event

◦ Action

◦ Activity

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Contain:◦ States

◦ Transitions

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Composite state with under state sequentially active:

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Composite state with under state parallel active:

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Used to model the dynamics of a process or operation

Highlights execution control from one activity to another

It is attached to:◦ A class (models an use case)

◦ A package

◦ Implementation of operations

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Model the hardware environment where the project will work

Example: to describe a web site a deployment diagram will contain hardware components for◦ web server,

◦ server applications,

◦ server database

Software components on each of these◦ The web application

◦ Database

◦ The way in which they are connected: JDBC, REST, RMI

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Package:◦ It is a logical container for elements between which we

have connections

◦ Defines a namespace

◦ All UML elements can be grouped into packages (most packages are used to group classes)

◦ A package may contain subpackages => creates a tree structure (similar to organizing files / folders)

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Relations:◦ dependence <<access>> = privat import

◦ dependence <<import>> = public import

Both relationships allow use of elements found in the destination package by the evidence in the source package without the need of qualifying the names of items in the package destination (similar to import directive in java)

These types of diagrams are provided in class diagrams

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Elements from Types are imported in ShoppingCart and then areimported by WebShop

Elements from Auxiliary can be accessed only from ShoppingCart and cannot be referred from WebShop

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Divide large systems into smaller and more manageable subsystems

Allowing iterative parallel development

Defining clear interfaces between packages forcode reuse (eg. Packages for graphic interface,for enabling connection to BD, etc ...)

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Diagrams are neither too complicated nor too simple: the goal is effective communication

Give suggestive names for components

Elements arranged so that the lines do not intersect

Try not to show too many kinds of relationships once (avoid complicated diagrams)

If necessary, make more diagrams of the same type

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Context, Containers, Components and Code

Provides different levels of abstraction, each of

which is relevant to a different audience

Avoid ambiguity in your diagrams by including a

sufficient amount of text as well as a key/legend

for the notation you use

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Shows the software system you are building

How it fits into the world in terms of the people who use it and the other software systems it interacts with

Colours - Systems already exist (the greyboxes) and those to be built (blue)

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Zooms into the software system, and shows the containers (applications, data stores, microservices, etc.)

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Zooms into an individual container to show the components inside it

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Zoom into an individual component to show how that component is implemented

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https://tobiashochguertel.github.io/c4-draw.io/

https://structurizr.com/express

https://www.infoq.com/articles/C4-architecture-model

https://c4model.com/

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A traditional process of moving from high-level abstractions and logical to the implementation-independent designs to the physical implementation of a system

FE follows a sequence of going from requirements through designing its implementation

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Reverse engineering (RE) is the process of discovering the technological principles of a device, object or system through analysis of its structure, function and operation

To try to make a new device or program that does the same thing without copying anything from the original

Reverse engineering has its origins in the analysis of hardware for commercial or military advantage

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Interoperability

Lost documentation

Product analysis

Security auditing

Removal of copy protection, circumvention of access restrictions

Creation of unlicensed/unapproved duplicates

Academic/learning purposes

Curiosity

Competitive technical intelligence (understand what your competitor is actually doing versus what they say they are doing)

Learning: Learn from others mistakes36

RE1: Reverse engineering of mechanical devices

RE2: Reverse engineering of integrated

circuits/smart cards

RE3: Reverse engineering for military

applications

RE4: Reverse engineering of software

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Rapid prototyping

FullCure materials

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RE is an invasive and destructive form of analyzing a smart card

The attacker grinds away layer by layer of the smart card and takes pictures with an electron microscope

Engineers employ sensors to detect and prevent this attack

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Satellite TV

Security card

Phone card

Ticket card

Bank card

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Reverse engineering is often used by militaries in order to copy other nations' technologies, devices or information that have been obtained by regular troops in the fields or by intelligence operations

It was often used during the Second World War and the Cold War

Well-known examples from WWII and later include: rocket, missile, bombers, China has reversed many examples of US and Russian hardware, from fighter aircraft to missiles and HMMWV cars

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US – B-29 URSS – Tupolev Tu-4

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Chinese J-20, Black Eagle US F-22, Russian Sukhoi T-50

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US -AIM-9 Sidewinder Soviet - Vympel K-13

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Reverse engineering is the process of analyzing a subject system to create representations of the system at a higher level of abstraction

In practice, two main types of RE emerge: ◦ Source code is available (but it is poorly documented)

◦ There is no source code available for the software

Black box testing in software engineering has a lot in common with reverse engineering

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public class Test

{

private int n;

private int m;

public static void main(String args[])

{

for(int i=1;i<10;i++)

System.out.println("Test");

}

}

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Link: http://www.steike.com/code/java-reverse-engineering/

jad.exe FileName.class => FileName.jad

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File -> Import Sources...

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Forward engineering:◦ Class diagrams -> .java files (ArgoUML)

◦ .java files -> .class files (NetBeans)

Reverse engineering: ◦ .class files -> .java files (JAD Decompiler)

◦ .java files -> Class Diagrams (ArgoUML)

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UML Diagrams:◦ Interactions

◦ Behavior

◦ Structure

C4 Model: context, container, component,

code

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Ovidiu Gheorghieş, Course 5 IP

www.uml.org

Reverse Engineering and Design Discovery: A Taxonomy, Chikofsky, E.J. and Cross, J., January, 1990

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DJ Java Decompiler 3.10.10.93: http://www.softpedia.com/progDownload/DJ-Java-Decompiler-Download-13481.html

Open Office: http://ro.wikipedia.org/wiki/OpenOffice.org UML Reverse Engineering for Existing Java, C# , and Visual Basic .NET Code:

http://www.altova.com/umodel/uml-reverse-engineering.html Reverse Engineering:

http://en.wikipedia.org/wiki/Reverse_engineering PROTO 3000 3D Engineering Solutions:

http://www.proto3000.com/services.aspx HAR2009: http://www.degate.org/HAR2009/ Degate: http://www.degate.org/screenshots/ Inteligent: http://www.intelligentrd.com/ Smartphones RE: http://www.cytraxsolutions.com/2011/

01/smartphones-security-and-reverse.html

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