Cellphone Hacks

526 Articles

Your Body Is Your PIN With Bodyprint

April 30, 2015 by 29 Comments

[Christian Holz, Senaka Buthpitiya, and Marius Knaust] are researchers at Yahoo that have created a biometric solution for those unlucky folks that always forget their smartphone PIN codes. Bodyprint is an authentication system that allows a variety of body parts to act as the password.  These range from ears to fists.

Bodyprint uses the phone’s touchscreen as an image scanner. In order to do so, the researchers rooted an LG Nexus 5 and modified the touchscreen module. When a user sets up Bodyprint, they hold the desired body part to the touchscreen. A series of images are taken, sorted into various intensity categories. These files are stored in a database that identifies them by body type and associates the user authentication with them. When the user wants to access their phone, they simply hold that body part on the touchscreen, and Bodyprint will do the rest. There is an interesting security option: the two person authentication process. In the example shown in the video below, two users can restrict file access on a phone. Both users must be present to unlock the files on the phone.

How does Bodyprint compare to capacitive fingerprint scanners? These scanners are available on the more expensive phone models, as they require a higher touchscreen resolution and quality sensor. Bodyprint makes do with a much lower resolution of approximately 6dpi while increasing the false rejection rate to help compensate.  In a 12 participant study using the ears to authenticate, accuracy was over 99% with a false rejection rate of 1 out of 13.

Continue reading “Your Body Is Your PIN With Bodyprint” →

A Cellular Dev Kit With A Data Plan

April 5, 2015 by 37 Comments

After years of futzing around with 433 MHz radios and WiFi, we’re finally seeing a few dev boards that are focused on cellular radio modules. The Konekt Dash is the latest offering that puts a small u-blox SARA cellular module on a board with a small ARM Cortex M4 microcontroller for a complete cellular solution for any project you have in mind. Yes, until we get radios that make sense for an Internet of Things, this is the best you’re going to get.

If the Konekt sounds familiar, you’re right. A few months ago, Spark introduced the Electron, a cellular dev board based on the u-blox SARA-U260 module that includes a SIM with a 1MB of data a month. Practically, it’s not much different from the Konekt, but the Dash and Dash pro offer battery management and a battery connector, two power supplies, and encryption from the board to a server. There are slight differences for about the same price, but that’s what’s great about competition.

The Konekt Dash is now a few days in to a Kickstarter campaign that includes as rewards a board and a SIM with a six months to a year’s worth of data. There are a lot of things that can’t be done with WiFi, Bluetooth, or other radio modules, and if you have something like that in mind, you won’t do better than a Konekt or Spark Electron.

The 2G Raspberry Pi Smartphone

April 4, 2015 by 32 Comments

For [Tyler]’s entry to the Hackaday Prize, he’s making something that just a few years ago would be unheard of in a homebrew build. He’s making a DIY smartphone. Yes, with cheap single-board Linux computers, GSM modules, and SPI touchscreen displays, it’s possible to build your own smartphone.

Inside [Tyler]’s DIY smartphone is a Raspberry Pi Model A, a 3.5 inch touchscreen PiTFT with 480×320 resolution, and an Adafruit FONA module The connections are simple enough; the TFT is connected over SPI, and the GSM module over serial. The entire device is powered by a 1200mAh LiIon battery, charged with a powerboost board, runs an operating system written in Python capable of making calls, sending texts, and takes pictures with a Pi camera.

This is not what you would normally call a smartphone. The FONA module is 2G only, meaning you’re limited to 2G speeds and 2G networks. AT&T will be shutting down 2G networks in a little bit, although T-Mobile will be keeping them up for anyone who still has an old Nokia Brick.

That said, [Tyler]’s phone is still exactly what you want in a minimal phone: it just makes calls and receives texts, it has a camera, and unlike the Nokia, you can take it apart and repair it easily. Not that you ever had to do that with a Nokia…

Spark Goes Cellular With The Electron

February 25, 2015 by 53 Comments

A few years ago, small and cheap WiFi modules burst onto the scene and with that the Spark was born. It’s a tiny dev board with a TI CC3000 WiFi module, capable of turning any device into an Internet-connected device. It’s only the very beginning of the Internet of Things, yes, but an important step in the right direction. Now, Spark is unshackling itself from WiFi networks with the Spark Electron, a dev kit that comes with a cellular radio and data plan.

If you’ve ever tried to build a high altitude balloon, a project that will be out of range of WiFi, or anything else where cellular data would be a godsend, you’ll quickly realize Verizon, AT&T, Sprint, and all the other carriers out there don’t necessarily care about your project. As far as we can tell, Spark is the first company to fix this gaping hole in what cellular can do by offering their own service – 20,000 messages for $3/month and no contracts. Officially, that’s 1MB of data spread over 20k messages that are about 50 bytes in length.

There are a few dozen companies and organizations working on the next generation of The Internet Of Things, but these require completely new silicon and spectrum allocations or base stations. Right now, there’s exactly one way of getting a Thing on the Internet without WiFi, and that’s with cellular data. We have to hand it to Spark for this one, and can’t wait to see the projects that will be possible due to a trickle of Internet everywhere.

MacGyver, Jedi Knights, Ammo Stockpiles, And Candy Crush

February 22, 2015 by 55 Comments

Everyone’s favorite machinist, tinkerer, YouTube celebrity, deadpan comedian, and Canadian is back with a tale of popping a few benzos, stumbling around Mexico, and wondering why everyone else on the planet is so stupid.

The hero of our story considered the feasibility of one hundred and eighty-sixth trimester abortions as he stood outside a Mexican airport watching a stockbroker complain about the battery in his cellphone. Meanwhile, cars drove by.

Here’s how you charge a phone with a car battery and an ‘ol Dixon Ticonderoga.

To charge a battery, all you really need to do is connect the terminals to a power source with the right voltage. A cell phone battery needs about three volts, and a car battery has twelve. You need a voltage divider. You can get that with a pencil. Take out a knife, get to the carbon and clay wrapped in wood, and wire the battery up. Make a cut a quarter of the way down this rather long resistor, and there you will find something around three volts.

Does it work? Yeah. It works even better if you have some tape to hold wires onto the cell phone battery when charging. Is it smart? It is if there is no other conceivable way of charging your cell phone. Should you do it? Nah. Video below. Thanks [Morris] for the link.

Continue reading “MacGyver, Jedi Knights, Ammo Stockpiles, And Candy Crush” →

Towards A Reverse Engineering Of Samsung’s S-Pen

February 22, 2015 by 13 Comments

A few years ago, Wacom, the company behind all those cool graphics tablets, teamed up with Samsung to create the S Pen, a rebirth of that weird pen computing thing that happened in the 90s and a very interesting peripheral if only someone would write some software for it. [Kerry D. Wong] was wondering how the S Pen worked and wired up some hardware to take a look at how the pen communicates with the phone.

It was already known that the S Pen was powered by an RF field, and works somewhat like RFID. Listening in on the communication would require a coil of some type, so [Kerry] disassembled a small speaker and connected it to a scope.

A look at the captured waveforms from the S Pen reveled the carrier frequency appears to be in the range of 550 to 560kHz, outside the range of standard RFID. He doesn’t have the equipment to decode the complete protocol, but a few things can be deduced – the screen senses the location of the pen by detecting a dip in the RF field strength. The only information that is transferred between the pen and phone is the 11-bit pressure sensitivity and a 1-bit value that signals the button is on or off.

[Kerry] put the waveform data up on his site should anyone want to make an attempt at decoding the protocol.

Hack Your Phone: Turn Your Volume Buttons Into GPIO Ports

February 15, 2015 by 9 Comments

Internet connected cameras are mighty useful, specially in situations requiring some form of remote monitoring. An always-on camera that is available over an internet connection, is cheap, and uses re-purposed  hardware – that’s what the Gonzo project hopes to achieve. To accommodate these requirements, the Exploratory Engineering program team in Telenor Digital are using off-the-shelf phone hardware running on top of a fork of Firefox OS. You hang the Gonzo where you want to monitor a situation, after which it will function for up to one month before needing a recharge, sending data to a designated public URL over the 2G network.

A big downside with using such hardware is that it is not designed for the task at hand, and offers no expansion ports that may be needed for certain functions. In this particular case, the designers needed a couple of output ports to drive some LED’s. The hardware guys got a bit creative,  and re-mapped the volume buttons of the phone into generic GPIO ports. On the software side, they looked at where the button GPIO’s were referenced, and located how they are mapped to a keymap. They then added a device driver that maps the GPIO ports to be generic ports instead. Modding the hardware needed a little bit more hard work, figuring out which traces connected to the two volume buttons, adding series resistors, and then wiring the LED’s in place. The project itself is still a work in progress, and you can read more about it at the Gonzo website.

If you’re like one of us and have a box full of old phones lying around, take a look at some creative suggestions here for some Arduino controlled robots.

Thanks for the tip [pb] !