Friday, May 26, 2023

Linux Command Line Hackery Series - Part 3


Welcome back, hope you are enjoying this series, I don't know about you but I'm enjoying it a lot. This is part 3 of the series and in this article we're going to learn some new commands. Let's get started

 Command: w
Syntax:      w
Function:   This simple function is used to see who is currently logged in and what they are doing, that is, their processes.

 Command:  whoami
Syntax:       whoami
Function: This is another simple command which is used to print  the  user  name  associated  with the current effective user ID.

 Try it and it will show up your user name.

 If you want to know information about a particular user no matter whether it is you or someone else there is a command for doing that as well.

 Command: finger
Syntax:      finger [option] [username]
Function:   finger is a user information lookup program. The [] around the arguments means that these arguments are optional this convention is used everywhere in this whole series.

 In order to find information about your current user you can simply type:

 finger username

 Here username is your current username.
To find information about root you can type:

 finger root

 and it will display info about root user.

 Command: uname
Syntax:      uname [options]
Function:   uname is used to display information about the system.

 uname is mostly used with the flag -a, which means display all information like this:

 uname -a

 Command: df
Syntax:      df [option] [FILE ...] 
Function:   df is used to display the amount of space available.
If you type df in your terminal and then hit enter you'll see the used and available space of every drive currently mounted on the system. However the information is displayed in block-size, which is not so much human friendly. But don't worry we can have a human friendly output as well using df by typing:

 df -h

 the -h flag is used to display the used and available space in a more user friendly format.
We can also view the info of a single drive by specifying the drive name after df like this:

 df -h /dev/sda2

 That's it for now about df, let's move on.

 Command:  free
Syntax:       free [options]
Function:    free is used to display the amount of free and used physical memory and swap memory in the system.
Again the displayed information is in block-size to get a more human readable format use the -h flag like this:

 free -h

 Command: cal
Syntax:      cal [options]
Function:    cal stands for calendar. It is used to display the calendar.

 If you want to display current date on the calendar you can simply type:

 cal

 and wohooo! you get a nice looking calendar on screen with current date marked but what if you want to display calendar of a previous month well you can do that as well. Say you want to display calendar of Jan 2010, then you'll have to type:

 cal -d 2010-01

 Nice little handy tool, isn't it?

Command: file
Syntax:      file filename ...
Function:   file is an awesome tool, it's used to classify a file. It is used to determine the file type.

 Let's demonstrate the usage of this command by solving a Noob's CTF challenge using file and base64 commands. We'll talk about base64 command in a bit. Go to InfoSecInstitute CTF Website. What you need to do here is to save the broken image file on your local computer in your home directory. After saving the file open your terminal (if it isn't already). Move to your home directory and then check what type of file it is using the file command:

 cd
file image.jpg

 Shocking output? The file command has identified the above file as an ASCII text file which means the above file is not an image file rather it is a text file now it's time to see it's contents so we'll type:

 cat image.jpg

 What is that? It's some kind of gibberish. Well it's base64 encoded text. We need to decode it. Let's learn how to do that.

 Command: base64
Syntax:       base64 [option] FILE ...
Function:    base64 command is used to encode/decode data and then print it to stdout.

 If we're to encode some text in base64 format we'd simply type base64 hit enter and then start typing the text in the terminal after you're done hit enter again and then press CTRL+D like this:

 base64
some text here
<CTRL+D>
c29tZSB0ZXh0IGhlcmUK        # output - the encoded string

 But in the above CTF we've got base64 encoded data we need to decode it, how are we going to do that? It's simple:

 base64 -d image.jpg

 There you go you've captured the flag.
The -d flag here specifies that we want to decode instead of encode and after it is the name of file we want to decode.

 Voila!
So now you're officially a Hacker! Sorry no certificates available here :)

 That's it for this article meet ya soon in the upcoming article.

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Posted by daybydaypregnancy at 11:38 AM

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Why Should you take care of Day by Day Pregnancy?


Taking care of your baby and your body on Day by Day Pregnancy

If you're pregnant now, you should know how important is to take care of yourself and your future baby. Well, pregnant is something that every married girl dream of. Sooner or later, after you married and settle down, your husband and yourself will love to have a new comer in your house, especially if only both of you living together without living with your other family members like your parents, grandparents or any other sibling

It is extremely important to take care of your baby and yourself on day by day pregnancy. You must eat the right food and make sure that the food you ate will not harm your baby and yourself.

Yes, pregnant is great, eating right and good nutrition food for your baby is a must! but how about the excessive pounds you will get when you're pregnant and after you delivered? is it something that you must consider of? as a woman, it is extremely important to take care of our weight, fat means ugly, and what happen when we're fat? of course, we will lost our self confident at first. And what happen when we lost our self confident?

If you're not even dare to look at yourself in the mirror, do you think that your belove husband will like to hug you, kiss you and look at you like before? even if your husband looks at you like before, you might probably think, "what's wrong with him, he look at my fat meat all the time!"

well, dont' let this happens to you. It is Extremely important to get rid of the excessive fat during and after pregnancy.

Here at Pregnancy Without Pounds, I found an absolutely great course and guide for your day by day pregnancy course, free of charge. They'll send you article and some guide several times a week for you to learn how to take care of yourself and your baby.

This is what they claim: