Kaotic, Kreation, Design

so you have your fresh new Ubuntu system and you log in via ssh to be greeted with

“Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

bla bal bla”

so you fire up vim and change the good ol /etc/motd to sometime a little more along the lines of threating anyone who misuses the system with the wrath of IT.

super your new MOTD works great untill you reboot the system. heres a little secret about Ubuntu notice the first line of the MOTD when you logd in the first time? The line about the kernel version and other system information? Well thats all there because Ubuntu generates the /etc/MOTD file during system startup so any changes you make to this file will be lost on the next reboot. Solution? Ubuntu generates the first line then appends the conents of /etc/MOTD.tail to the end and saves it as /etc/MOTD.

so to use your new MOTD you need to save your message to /etc/MOTD.tail

written by Brandon Leon \\ tags: Configuration, Howto, Linux, SSH

A while ago I wrote a bit about Shared Key Authentication for SSH, and discussed a bit about the benefits of enabling this on your own servers or even desktops. one of which is protecting your server against brute force attacks. However we never discussed that in order for your system to be truly protected from a brute force attack on your password you need to disable password authentication on your server. Please note before attempting this make sure that your keys work because if your configuring your server remotely and you disable password authentication you will lock yourself out. Once you are sure that you can log into the remote host using your private key, we can safely disable the user name/password authentication.

The procedure to set this up is extremely simple. I’ll be showing you this on a Ubuntu Server install with OpenSSH but the procedure is similar on other setups. On a Ubuntu server the file will be located in /etc/ssh/sshd_config. your going to want to add the following to the config file (or change the values if they already exist.

Once you save the changes you’ll need to reload the SSH server with the following command.

Thats it, your server should no longer accept user name/password authentication.

written by Brandon Leon \\ tags: Authentication, Howto, Linux, security, SSH

There is a few reasons you may want to do this, and this is the main reason most people do not jailbreak there phones, last time I headed up north to spend some time with my family I arived pretty early as I took off work early to head up to Hanford (I arrived at about 7AM). My sister usually gets up around 11 to noon so I snuck in her room and snagged her iPhone off her desk and jailbroke it before she woke up. She was surprised to find her Springboard with new app icons and a background behind the icons.

Just so some of her friends wouldn’t mess with it I removed installer.app after I finished so they could not install anything else on the phone. All my sister was interested in was the styled icons anyway.

We’ll this goes to show you how easy it is to restore the phone, a few weeks later her screen went out and stopped accepting any input it would display things fine but would not accept any input. before I even found out about it she had restored the phone back to default settings, Still nothing. Turns out her screen went bad she took it to the apple store and they replaced it with a new unit on the spot.

All you have to do is toss it in iTunes and select “Restore” from the main iPhone page. it will even back up your phone book, contacts, even your text messages, mail and call log. You’ll end up with a stock iPhone with no data lost, other than for any custom applications that is.

So yes technically Jailbreaking your phone will void the warranty, but after a simple restore, Apple wont know. =)

written by Brandon Leon \\ tags: iPhone, Jailbreak