shekkbuilder

Bash scripting cheatsheet

• by Lee2sman
• Updated 2017-09-18

Bash shebang

• #!/usr/bin/env bash for portability, or less good, #!/bin/bash

Commenting

shekkbuilder

# cat notes/how_to_admin
This is what I tell people to do, who ask me "how do I learn to be a Linux sysadmin?".

1) Set up a KVM hypervisor.
2) Inside of that KVM hypervisor, install a Spacewalk server. Use CentOS 6 as the distro for all work below. (For bonus points, set up errata importation on the CentOS channels, so you can properly see security update advisory information.)
3) Create a VM to provide named and dhcpd service to your entire environment. Set up the dhcp daemon to use the Spacewalk server as the pxeboot machine (thus allowing you to use Cobbler to do unattended OS installs). Make sure that every forward zone you create has a reverse zone associated with it. Use something like "internal.virtnet" (but not ".local") as your internal DNS zone.
4) Use that Spacewalk server to automatically (without touching it) install a new pair of OS instances, with which you will then create a Master/Master pair of LDAP servers. Make sure they register with the Spacewalk server. Do not allow anonymous bind, do 

shekkbuilder

Let's Start (Weekend Notes) ...

Install debootstrap :

$ apt-get install debootstrap

Minimal Debian distribution with debootstrap :

shekkbuilder

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;
;;; Copyright (C), zznop, zznop0x90@gmail.com
;;;
;;; This software may be modified and distributed under the terms
;;; of the MIT license.  See the LICENSE file for details.
;;;
;;; DESCRIPTION
;;;
;;; This PoC shellcode is meant to be compiled as a blob and prepended to a ELF

shekkbuilder

#      ___             ___ __      __
#     /   | __  ______/ (_) /_____/ /
#    / /| |/ / / / __  / / __/ __  / 
#   / ___ / /_/ / /_/ / / /_/ /_/ /  
#  /_/  |_\__,_/\__,_/_/\__/\__,_/   
#                                    
# Linux Audit Daemon - Best Practice Configuration 
# /etc/audit/audit.rules
#
# Compiled by Florian Roth

shekkbuilder

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

shekkbuilder

Download Audio from YouTube

-i - ignore errors

-c - continue

-t - use video title as file name

--extract-audio - extract audio track

shekkbuilder

Linux可執行文件ㄉ內容分析工具

NOTE: This is a working copy. This tutorial is unfinished and may contain inaccuracies.

I've written the title of this tutorial in Chinese, as I suspect that its contents may, at first glance, appear similarly incomprehensible to the audience.

However, just as I can sketch for you the following...

可執行文件 = (可 = can) + (執行 = execute) + (文件 = file) = executable (file)

shekkbuilder

Linux可執行文件ㄉ內容分析工具

NOTE: This is a working copy. This tutorial is unfinished and may contain inaccuracies.

I've written the title of this tutorial in Chinese, as I suspect that its contents may, at first glance, appear similarly incomprehensible to the audience.

However, just as I can sketch for you the following...

可執行文件 = (可 = can) + (執行 = execute) + (文件 = file) = executable (file)

shekkbuilder

#!/bin/bash

# this tool will automate firmware extraction and unpacking using FT232R-type adaptors (like BusPirate) and a SOIC clip placed on a chip to dump
# install the necessary software:
#$ sudo apt install flashrom binwalk || echo 'git clone?'
# pump up binwalk with additional packages and libraries
#$ bash <(curl -s https://raw.githubusercontent.com/devttys0/binwalk/master/deps.sh)
# place the clip on the chip, connect it to the adaptor, which sould be connected to your PC (with drivers installed) and launch the script:
# chip => clip => adaptor => PC => script