Ever wanted to feel like one of those movie hackers from the late 90s? Yes, your basement’s full of overclocked Linux rigs and you’ve made sure all your terminal windows are set to green text on a black background, but that’s not always enough. What you need is an RFID tag that unlocks your PC when you touch the reader with your RFID card. Only then may you resume blasting away at your many keyboards in your valiant attempts to hack the mainframe.
[Luke] brings us this build, having wanted an easier way to log in quickly without foregoing basic security. Seeing as an RC522 RFID reader was already on hand, this became the basis for the project. The reader is laced up with a Sparkfun Pro Micro Arduino clone, with both devices serendipitously running on 3.3V, obviating the need for any level shifters. Code is simple, based on the existing Arduino RC522 library. Upon a successful scan of the correct tag, the Arduino acts as a HID keyboard and types the user’s password into the computer along with a carriage return, unlocking the machine. Simple!
Overall, it’s a tidy build that achieves what [Luke] set out to do. It’s something that could be readily replicated with a handful of parts and a day’s work. If you’re interested in the underlying specifics, we’ve discussed turning Arduinos into USB keyboards before.
We’ve got two hacks in one from [Serge Rabyking] on fingerprint scanning. Just before leaving on a trip he bought a laptop on the cheap. He didn’t pay much attention to the features and was disappointed it didn’t have a fingerprint scanner. Working in Linux he uses sudo a lot and typing the password is a hassle. Previously he just swiped his finger on the scanner and execution continued.
He found a cheap replacement fingerprint scanner on hacker’s heaven, also known as eBay. It had four wires attached to a 16 pin connector. Investigation on the scanner end showed the outer pair were power and ground which made [Serge] suspect it was a USB device. Wiring up a USB connector and trying it the device was recognized but with a lot of errors. He swapped the signal lines and everything was perfect. He had sudo at his finger tip.
Next he wonder if it would work with a Raspberry Pi. He installed the necessary fingerprint scanning software, ran the enrollment for a finger, and it, not terribly surprisingly, worked.
On Linux the command fprintd-enroll reads and stores the fingerprint information. By default it scans and saves the right index finger but all ten fingers can be scanned and stored. Use libpam-fprintd to enable account login using a finger. Anyone know how you can trigger other events using a different finger? A quick search didn’t turn up any results.
In true hacker style, [Serge] created his own fingerprint reader from a replacement part. But you can jump start your finger usage by purchasing one of many inexpensive available readers.
[Jair2K4] is using his unique RFID tag address as an online password. We’d bet that if you went far enough to get an implant in your hand you’d continually search for a reason to use it. Wanting to do more than just start his car with a wave of the hand, he built an interface module out of an Arduino and a Parallax RFID reader. Using a program called AAC Keys on Windows 7 he emulates a keyboard using the input from the Arduino. When it comes time to login he types his username and parks the cursor in the password box. By holding the RFID implant next the reader, the ID is dumped as the password, along with a newline (might be a carriage return, we’re not certain) character which submits the login. Take a look for yourself after the break.
On the one hand, nobody will be able to steal his tag as easily as they could steal one that is on a key ring. But we know RFID is rather notorious for a false sense of security. As long as you’re not using it for state secrets we think it’s a nice solution.
Update: After reading the comments on this feature, [Jair2K4] made some changes to his code. It now reads the tag and verifies it with stored data, then spits out whatever password you wish (making it easy to change passwords from time-to-time). He also added servo control to the sketch.
Continue reading “Embedded RFID For Online Passwords”