GoodFET

It aint pretty, but its mine and its working

The good neighbour @travisgoodspeed was generous enough to offer free GoodFET boards to hackerspaces and the like. For the local OWASP chapter I asked if we could have some – the result can be inspected in a previous post. So now I had 12 GoodFET boards on my hands and it wasn’t what I expected at all. First of all I thought they were going to be fully populated, functional and ready to be used – these were only the PCBs. Secondly I thought we were going to get one board.

This presented me with two interesting problems, first of all I needed to acquire a lot of components and secondly I needed a crew that could put the GoodFETs to good use. The first problem was easy to overcome, me and som friends recently assembled a couple of Ubertooths so I knew how and where to place an order. The second problem had a pretty obvious solution as well; a OWASP hardware hacking introduction course, where the participants would build their own GoodFETs and learn how to solder SMBs. With three instructors, there was only 9 seats in the course and they were gone within 24 hrs. A video from the event is available at OWASP Göteborgs YouTube-channel.

Out of 12 kits, 1 was pre-built (one of the instructors got carried away) and 11 was to be built during the course. The result was pretty OK; 1 kit died early in the evening – that is what happens when you give a soldering iron to a PHP-developer and pentester. 7 kits were fully functional and the remaining three was in different states of “close, but not enough”. One of them is a mystery; I supervised the entire build and it was perfect – a lot better than my board. The participant was meticulous in his preparations and the soldering was outstanding. But the board just didn’t want to cooperate.

Anyway – we hade a great evening and learned a lot all thanks to Travis. We have two follow up sessions planned; another session with the same approach so that more people will be able to solder their own boards and then a session where we put the GoodFET to good use – I am a little interested in getting my hands on a fairly modern wireless home alarm. But that is probably a much to complex target for a training course. Probably it’s better to aim for a target where work has already been done and tools are available.

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Übertooth

Intro

During the spring 2011 I stumbled upon Michael Ossmann’s  presentation from ShmooCon regarding the open source hardware bluetooth dongle he developed and i got really inspired. I wanted one of those! At that moment Micheal had just started a Kickstarter project but the delivery was a couple of weeks away and I saw this as an opportunity to get back into electronics and soldering and at the same time get acquainted with SMB – I didn’t even know it was possible to perform SMB soldering at home. So I went for doing it all by my self.

Another one of my decision that wasn’t all that clever…

Open heart surgery

The Scene: You are in the djungle (or rather, on vacation in the family cabin in the woods) and your broadband dongle is physically broken due to low intelligence use of a empty microSIM-card adapter (I refuse to disclose details). You really need to get in contact with civilization.

The Problem: The broadband dongle refuses to accept the SIM, the pins will not connect to the smart card since at least one of them is broken and/or displaced.

The Tools: Safety pin, tape, utility knife and an old rusty hacksaw blade

The operating table and some left over parts…

The Solution: Violence.
I have little to loose since it just isn’t working at the moment. Perhaps I could open up the SIM connector and fix the pins?
Now, the dongle is pretty compact and built more or less solely using surface mounted SMB components and the only possible entry in to the microelectronic fortress was through some really small phillips screws.

Tools of choice

I managed to use the tip of the utility knife to get the two screws out of the way and when a third hidden screw was detected it got the same treatment. Some serious bending, cutting and a 20 minute sawing session later the result was an open SIM tray and the cold fact that two out of eight pins were completely gone – only some miniscule copper ends protruded from the underlying electronics.

The use of precision force in combination with safety pin and utility knife moved the pin ends into a position as close to ideal as possible under the circumstances.

Time to test – SIM into the microSIM adapter, uSIM adapter placed roughly in the correct position and a piece of masking tape to hold it all in place. A short moment of “should-i-relly-put-this-electronic-Frankenstein-monster-in-my-brand-new-MacBookPro” later the dongle was inserted and to my complete surprise the popup asked for the PIN for the SIM!

A fully recovered patient

Not even the curious and not-so-gentle fingers from a 2 year old could kill my creation – it was ALIVE!

The entire purpose of getting online failed since I couldn’t solve the issue anyway, but it didn´t really matter – I was super pleased with the open heart surgery!