Verify the integrity of downloaded ISO files

You should always verify any downloaded ISO file. The reason is that the file may have been maliciously modified by a hacker and can install malware like backdoors, keyloggers etc into your computers.

The ISO file is signed using the private key to create a digital signature. The public key is used to verify the signature. The digital signature file is used to verify the ISO file.

This verifies that the file has been created by the owner himself, since nobody else has his private key. Also, it verifies that the file has not been modified or tampered in any way. 

1) Download the ISO file.

[shabbir@block1 Downloads]$ wget https://github.com/Security-Onion-Solutions/security-onion/releases/download/v14.04.4.1/securityonion-14.04.4.1.iso


2) Download the digital signature for the above downloaded ISO file.

[shabbir@block1 Downloads]$ wget https://github.com/Security-Onion-Solutions/security-onion/raw/master/securityonion-14.04.4.1.iso.sig


3) Download the public key.

[shabbir@block1 Downloads]$ wget https://raw.githubusercontent.com/Security-Onion-Solutions/security-onion/master/KEYS

4) Import the public key in your public keyring.
[shabbir@block1 Downloads]$ gpg --import KEYS

5) View your public keyring
[shabbir@block1 Downloads]$ gpg2 --list-keys
/home/shabbir/.gnupg/pubring.gpg
--------------------------------
pub   4096R/ED6CF680 2012-06-29
uid                  Doug Burks <doug.burks@gmail.com>
sub   4096R/C5D9F4EB 2012-06-29

6) Verify the ISO file using the signature file.
[shabbir@block1 Downloads]$ gpg --verify securityonion-14.04.4.1.iso.sig securityonion-14.04.4.1.iso
gpg: Signature made Sat 19 Mar 2016 05:32:50 PM IST using RSA key ID ED6CF680
gpg: Good signature from "Doug Burks <doug.burks@gmail.com>"
gpg: WARNING: This key is not certified with a trusted signature!
gpg:          There is no indication that the signature belongs to the owner.
Primary key fingerprint: BD56 2813 E345 A068 5FBB  91D3 788F 62F8 ED6C F680

Creating Encrypted volumes using Truecrypt in Kali Linux

TrueCrypt is a software for establishing and maintaining on the fly encrypted volumes. On the fly encryption means the data is automatically encrypted before it is saved and decrypted before it is loaded without user intervention.

1) Open TrueCrypt
root@kali:~# truecrypt

A Gui window will open

2)Click on Create Volume.



3)Select option Create an encrypted file container as shown below.














This option creates a container containing encrypted files. This files can be of any type as long as they are in conatiner they are encrypted

4)Select the option Standard TrueCrypt volume.

5)Specify the location for the container
               /root/Desktop/try

6)Specify the encryption standard.

7)Select the size of volume you want.
        It displays free space below the box used to specify size
     

        
8) Set password for encryption.

9) Select Filesystem you want on that volume

10) Select I will mount th evolume only on linux

11) Click on format

//Mount Volume to use it to create files and directories
 1)Select one of the slot in the list and select file volume file
             

 2) Click on Mount to mount this volume

3)now from terminal acess this volumeor u can use GUI
            root@kali:~# df
Filesystem             1K-blocks    Used Available Use% Mounted on
rootfs                  11459808 9637072   1217552  89% /
udev                       10240       0     10240   0% /dev
tmpfs                     102488     508    101980   1% /run
/dev/mapper/kali-root   11459808 9637072   1217552  89% /
tmpfs                       5120       0      5120   0% /run/lock
tmpfs                     204960      84    204876   1% /run/shm
/dev/sda1                 233191   26050    194700  12% /boot
/dev/mapper/truecrypt1     30356     430     27436   2% /media/truecrypt1

4) Change directory to /media/truecrypt1 and create files and directories
                root@kali:~# cd /media/truecrypt1/
                   root@kali:/media/truecrypt1# mkdir first
                   root@kali:/media/truecrypt1/first# touch foo1

5) unmount volumes using terminal or Gui
          1) For Gui Click on Dismount in Truecrypt
          2) For Terminal goto root directory and unmount truecrypt1
                      root@kali:/# umount /media/truecrypt1



              

AJAX in Ruby On Rails: Sample Application

1) Create a new project. Generate Model and Controller

[shabbir@neutron Aptana Studio 3 Workspace]$ rails new ajax1

[shabbir@neutron Aptana Studio 3 Workspace]$ cd ajax1/

[shabbir@neutron ajax1]$ rails generate model Task name:string 

[shabbir@neutron ajax1]$ rake db:migrate 

[shabbir@neutron ajax1]$ rails generate controller tasks index


2) routes.rb

  resources :tasks

  root 'tasks#index'


3) task_controller.rb

class TasksController < ApplicationController
  def index
    @tasks = Task.all
  end

  def new
    @task = Task.new
  end

  def create
    @task= Task.new(task_params)
    @task.save
   
    @tasks = Task.all
  end     

  def edit
    @task = Task.find(params[:id])
  end
 
  def update
    @task = Task.find(params[:id])
    @task.update(task_params)

    @tasks = Task.all
  end

  def destroy
    @task = Task.find(params[:id])
    @task.destroy

    @tasks = Task.all
  end
 
  private
  def task_params
    params.require(:task).permit(:name)
  end
end


4)  Views

When the user clicks on the "New Task" link, an AJAX request is sent to the server since "remote: true' is set.
index.html.erb

<div>
    <%= link_to "New Task" , new_task_path, id: "new_link", remote: true %>
</div>

<div id="task_form" style="display:none">
</div>

<h2> List All Tasks </h2>

<div id="tasks">
<%= render 'list' %>
</div>


When the user clicks on the "Edit" or "Delete" links, an AJAX request is sent to the server since "remote: true' is set.
_list.html.erb

<table>
<tr>
    <th>Name</th><th colspan="3"></th>       
</tr>   
<% @tasks.each do |task| %>
    <tr>
        <td><%= task.name %> </td>
        <td><%= link_to 'Edit', edit_task_path(task), remote: true %></td>
        <td><%= link_to 'Delete', task, method: :delete, data: {confirm: 'Are you sure ?'}, remote: true %></td>
       
    </tr>
<% end %>
</table>





When the user submits the form, an AJAX request is sent to the server since "remote: true' is set.
  _form.html.erb

<%= form_for @task, remote: true do |f| %>

<%= f.label :name %>
<%= f.text_field :name %>

<%= f.submit "Save" %>
<% end %>


5) Javascript


When the user clicks on the "New Task" link, the form is displayed and the "New Task" link is hidden.  
new.js.erb

$("#new_link").hide();

$("#task_form").html("<%= j (render 'form') %>");

$("#task_form").slideDown();



After the Task is created, the "New Task" link is displayed ,the form is hidden and the list of tasks is updated.

create.js.erb

$("#new_link").show();

$("#task_form").slideUp();

$("#tasks").html("<%= j (render('list')) %>" );




When the user clicks on the "Edit" link, the form is displayed and the "New Task" link is hidden.  

edit.js.erb

$("#new_link").hide();

$("#task_form").html("<%= j (render 'form') %>");

$("#task_form").slideDown();


After the Task is updated, the "New Task" link is displayed ,the form is hidden and the list of tasks is updated.

update.js.erb
$("#new_link").show();

$("#task_form").slideUp();

$("#tasks").html("<%= j (render('list')) %>" );


When the user clicks on the "Delete" link, the task is destroyed and the list of tasks is updated.

destroy.js.erb
 $("#tasks").html("<%= j (render('list')) %>" );