Black Hat Bash - Bash Scripting for Hackers and Pentesters (Early Access) (Dolev Farhi, Nick Aleks)

Now we can run the aliased command using the name of the alias:

$ quicknmap

Starting Nmap 7.80 ( https://nmap.org ) at 2023-02-21 22:32 EST

--snip--

PORT STATE SERVICE

631/tcp open ipp

You can even assign an alias to your own scripts:

$ alias helloworld="bash ~/scripts/helloworld.sh"

Aliases aren’t permanent, but they can be. In the next section, you’ll learn

how to use bash profiles to make permanent changes to your shell.

Customizing the Bash Run Commands Profile (bashrc)

We can use the ~/.bashrc file to load functions, variables, and just about any

other custom bash code we desire into a new bash session. For example, we can

create variables containing information we’ll frequently need to access, such as the

IP address of a vulnerable host we’re testing.

For example, we could append the following to the end of the ~/.bashrc file.

These lines define a few custom variables and save our aliased Nmap command:

VULN_HOST=1.0.0.22

VULN_ROUTER=10.0.0.254

alias quicknmap="nmap -vv -T4 -p- -sV --max-retries 5 example.local"

The next time you open a terminal, you’ll be able to access these values. Make

these new values available immediately by re-importing the ~/.bashrc file using

the source command:

$ source ~/.bashrc

$ echo $VULN_HOST

10.0.0.22

$ echo $VULN_ROUTER

10.0.0.254

Now you can use these variables even after you close the terminal and start a

new session.

Importing Custom Scripts

Another way to introduce changes to your bash session is to create a dedicated

script that contains pentesting-related customizations and have the ~/.bashrc file

import it using the source command. To achieve this, create a ~/.pentest.sh file

containing your new logic, and then make a one-time modification to ~/.bashrc to

import it at the end of the file:

source ~/.pentest.sh