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

Note that you can also source a bash file using the . command, as in Listing

42.

. ~/.pentest.sh

Listing 2-42

An alternative to the source command

Capturing Terminal Session Activity

Penetration testing often involves having dozens of terminals open

simultaneously, all running many tools that can produce a lot of output. When we

find something of interest, we may need some of that output as evidence for later.

To avoid losing track of an important piece of information, we can make use of

some clever bash.

The script command allows us to capture terminal session activity. One

way to use it is to load a small bash script that uses script to save every session

to a file for later inspection. The script might look like this:

#!/bin/bash

FILENAME="$(date +%m-%d-%y)_${RANDOM}.log"

if [[ ! -d ~/sessions ]]; then

mkdir ~/sessions

fi

# Starting a script session

script -f -a "~/sessions/${FILENAME}"

Having ~/.bashrc load this script, as showed earlier, will result in the creation

of the ~/sessions directory containing each terminal session capture in a separate

file. The recording stops once you enter exit in the terminal or close the entire

terminal window.

Exercise 2: Pinging a Domain

In this exercise, we’ll write a bash script that accepts two arguments: a name

(for example, mysite) and a target domain (for example, nostarch.com). The script

should also be able to do the following:

1. Throw an error if the arguments are missing and exit using the right status

code.

2. Ping the domain and return an indication of whether the ping was

successful or not.

3. Write the results to a CSV file containing the following information:

The name provided to the script

b. The target domain provided to the script