Category: Linux

  • Updating Kali Linux from behind a restrictive proxy

    I installed Kali Linux from the mini ISO, so I ended up with a fully functioning Linux system but with little to no tools (just nmap and ncat). In order to install the tools that are making Kali what it is, I had to install the metapackages. For me, the easiest option was to install all of…

  • Updating your Raspberry Pi

    Once you’ve installed Raspbian on your Raspberry Pi, it’s time to upgrade the Pi and the OS. Four simple commands: # sudo apt-get install rpi-update # sudo rpi-update # sudo apt-get update # sudo apt-get upgrade

  • Installing Raspbian from scratch without a keyboard or a monitor

    So, you got your Raspberry Pi, a nice SD card, but you can’t remember the last time you saw a keyboard and the only thing around you is a laptop with Windows. Don’t worry, there’s a simple solution. Download the latest version of Raspbian and Win32 Disk Imager. Start Win32 Disk Imager (“Run as Administrator”).…

  • Change MAC address in iOS for iPhone/iPad

    In older versions it used to be as easy as: # ifconfig en0 ether xx:xx:xx:xx:xx:xx For iOS versions >5 you have to resort to nvram: # nvram wifiaddr=xx:xx:xx:xx:xx:xx and then reboot the device. Prerequisite: jailbroken device, terminal access (local or SSH) and sudo.

  • Traffic mirroring in Linux

    It comes in hand when analyzing traffic to forward a copy of the traffic to a specific IP where a machine is listening and running Wireshark & stuff. It’s very useful for routers that don’t have the capabilities to run network analysis tools (like DD-WRT). Just run the following commands replacing the field with the…

  • Permanent IP forwarding in Linux

    We usually do # echo 1 > /proc/sys/net/ipv4/ip_forward when we want to enable forwarding in Linux. If you want to make this change permanent, you need to edit the /etc/sysctl.conf file and add or uncomment the following line net.ipv4.ip_forward = 1

  • Webmin and Virtualmin installation on Debian

    Now that we have a fresh and clean Debian installation we can proceed to Webmin and Virtualmin installation. Althou installing Apache, MySQL and other stuff needed for a web server by hand is not hard and you can find a lot of support I prefer installing Webmin and Virtualmin to ease the administrative tasks. If…

  • Install a clean Debian on Virtualbox

    I don’t test my ‘ideas’ on live servers, nor do I keep unnecessary hardware around the house to play with them. So I use the other option in hand, a virtual machine. Despite the fact that this will be a VM installation of Debian, the idea for a very clean and basic installation is the…

  • [Tool] Check if an email address is valid – the php way

    In an older post we talked about checking the validity of an email address. Now let’s make a php function to automate this task. We can use this type of validation to check for example if a user is using a correct address when registering for a service.

  • Check if an email address is valid – the telnet way

    You can use telnet to check if an email is valid. You can actually send emails via telnet, but we’ll stick to checking for now. Remember that this is not a string validation but a complete check with the mail server if the user is valid. For this example we will use [email protected].