Mostafa Menessy & Hesham shabana

Ruby

Outline

- Ruby Building Blocks Bot Network- Code Samples Ruby On Rails PE Packer- Advantages/Disadvantages Of Ruby- Ruby Internals ( if there is enough time )

Ruby Building Blocks - Data types

- Built-in data types aren’t declaredx=5 ; y = “10” ; z = [] , f = { "a" => 100, :b => 5 }x = Array.new ; x = [] ; x << "Word" ; puts x.pop ; puts x.length

- Data types can dynamically change during runtime execution.- Constants are defined by Capitalizing the first letter

Ruby Building Blocks - Control FlowCONDITIONS : :if tall < 150 puts "You can’t be a pilot"elsif tall > 220puts "You’re unique"end

puts "You're a teenager" if age > 12 && age < 20

puts"You're NOT a teenager" unless age > 12 && age < 20

x=20,y=12

puts "You're NOT a teenager" if x <=> y == 1

EXCEPTION:

if y == 0

raise ZeroDivisionError

else

x=x/y

end

begin... code here ...rescue ZeroDivisionError... code to rescue the zero division exception here ...rescue YourOwnException... code to rescue a different type of exception here ...rescue... code that rescues all other types of exception here … retryend

Ruby Building Blocks-LOOPS/BLOCKS5.times do ...code to loop here... end

5.times { ...code to loop here... }1.upto(5) { ...code to loop here... }10.downto(5) { ...code to loop here... }0.step(50, 5) { ...code to loop here... }

"xyz".scan(/./) { |letter| puts letter if letter == ‘x’ else redo }

"xyz".scan(/./) { |letter| puts letter if letter == ‘x’ else retry }

[1, "test", 2, 3, 4].each { |element| puts element.to_s }i = 1i = i * 2 until i > 1000while (i < a.length)puts a[i].to_s + "X"i += 1end

for i in 5..9 for i in 5...9 puts i puts iend end

class Array def reverse_iterate if block_given? current_index = self.size-1 while current_index >= 0 yield self[current_index] current_index -= 1 end else print self.reverse end endend

[2,4,6,8].reverse_iterate 8642[2,4,6,8].reverse_iterate { |x| puts x }8642

Ruby Building Blocks - OOP

- All of the constructs of the language are treated as objects. Checking the data types is done through *.class class the_class

attr_accessor :length

attr_reader : getter_only

def name@name

enddef name=(name)

@name = nameend

end

example = the_class.new

class Documentattr_accessor: magic_word

def initialize w, h@width, @height = w, hend

def [](index)words[index]end def ==(other) return magic_word == other.magic_wordendend

$global_var = “”class Example < SuperExample@@counter = 0@instance_counter = 0def initialize

@@counter += 1@instance_counter = @@counter superend

end

Packets through a Bot

Primitive C&C Network

Cont’d -- Payload

Who hates Vodafone ?

What is Rails

- Open source web application framework written in Ruby language

- Built using the MVC pattern

Rails Application

- Convention over configuration- DRY

- save time- reuse code- maintain

rails [app_name] -d mysql

Folder structureapp/ Contains the controllers, models, views, helpers, mailers and assets for your application.

app/controller The controllers subdirectory.

app/view The models subdirectory.

app/model The views subdirectory.

config/ Configure your application's runtime rules, routes, database, and more.

db/ Contains your current database schema, as well as the database migrations.

public/ The only folder seen to the world as-is. Contains the static files and compiled assets.

assest/ Contains the images, style sheets, javascript.

test/ Unit tests, fixtures, and other test apparatus.

mailers/ Contains the email, templates.

The MVC pattern

The Model View Controller principle divides the work of an application into three separate but closely cooperative subsystems.

The MVC pattern

MVC - Model

Rails Active Record - Rails Active Record is the Object/Relational Mapping (ORM) layer: tables map to classes,rows map to objects and columns map to object attributes

- Each Active Record object has CRUD (Create, Read, Update, and Delete) methods for database access.

MVC - Model: Implementation

rails generate model book

Associations: (one-to-one, one-to-many)class Book < ActiveRecord::Base belongs_to :subjectendclass Subject < ActiveRecord::Base has_many :booksend

MVC - Controller

- Separates businesslogic from the presentation.

- rails generate controller book

class BookController < ApplicationController def list end def show end def new end def create end def edit end def update end def delete endend

MVC - Controller: ImplementationImplementing the list Method:def list @books = Book.find(:all)end

Implementing the show Method:def show @book = Book.find(params[:id])end

Implementing the create Method:def create @book = Book.new(params[:book]) if @book.save redirect_to :action => 'list' else render :action => 'new' endend

MVC - View

- A Rails View shares data with controllers through accessible variables.

Create Action:<h1>Add new book</h1><%= start_form_tag :action => 'create' %><p><label for="book_title">Title</label>:<%= text_field 'book', 'title' %></p><p><label for="book_price">Price</label>:<%= text_field 'book', 'price' %></p><%= submit_tag "Create" %><%= end_form_tag %><%= link_to 'Back', {:action => 'list'} %>

Submit Action:<form action="/book/create" method="post">

Back Action:<form action="/book/list" method="post">

<% … %> Execute a ruby code

<%=…%> Execute and output the result

RoutesRoute:

match ':controller(/:action(/:id))(.:format)'http://mysite/user/get/5http://mysite/article/ruby-on-rails.html

Custome:get 'signup', to: 'users#new', as: 'signup'http://mysite/signup

All together

Portable executable EncryptionPrimitive PE Protector

- Encrypt the .text section data

- Append a new stub section for decrypting the data during runtime

- Adjust the PE Header ( AddressOfEntryPoint )

Ruby PE PACKER

[(Disa)|A]dvantages Of Ruby

- Senior Ruby on Rails engineer: One of the top 5 jobs in Silicon Valley

- Perfectly suits the startup environment

- Good Contribution by the community: over 4k rubygems, and a wide range of built -in modules

- For learning how to implement a new language

Cont’d

- Original MRI is relatively slow

- Errors don’t help so much in fixing problems

Different Implementations: Does it sound good or bad ?

Ruby Internals ( Extra )

Is it really an interpreter ? 1.8 <= Ruby version

- Its own custom tokenization code

- LALR Bison parser generator Involved , Parse.y and Parse.c in the ruby source folders

YARV is Another Ruby VM

Cont’d

Extract from Ruby Under A microscope

Questions

?