Inject Keystrokes Any Way You Like With This Bluetooth Keystroke Injector

[Amirreza Nasiri] sends in this cool USB keystroke injector.

The device consists of an Arduino, a Bluetooth module, and an SD card. When it’s plugged into the target computer the device loads the selected payload from the SD card, compromising the system. Then it does its unique trick which is to switch the injector over to Bluetooth mode. Now the attacker has much more control, albeit local, over the system.

While we would never even be tempted to plug this device into a real computer, we like some of the additional features, like how an added dip switch can be used to select from up to eight different payloads depending on the required attack. The addition of a photo diode is also interesting, and makes us dream of all sorts of impractical movie hacker scenarios. [Amirreza] says it’s to trigger when the person leaves the room and turns the lights off.

[Amirreza] has all the code and design files on the GitHub. There are also a few payload examples, which should be fun to hack on. After all, one of life’s pleasures is to find new ways to mess with your friends.

DIY Photo Backup In The Field

They say a file isn’t backed up if it isn’t backed up twice. This is easy enough to do if you have access to your computer and a network, but if you’re a photographer you might end up in a place without either of these things and need a way to back up the files you just created. For that you’ll need a specialized photo backup tool which you can easily build yourself.

While commercial offerings are available which back up files locally from a camera’s SD card to another medium, they suffer from a high price. [André]’s solution can be had for a fraction of that cost. Using a Raspberry Pi Zero, a tiny USB hub, and a high capacity jump drive, a photographer can simply plug in an SD card and the Pi will handle the backups with varying levels of automation. The software that [André] made use of is called Little Backup Box written by [Dmitri Popov] and can be used typically as an automatic backup for any other device as well.

This is a great solution to backing up files on the go, whether they’re from a camera or any device that uses an SD card. Removable storage is tiny and easily lost, so it’s good to have a few backups in case the inevitable happens. Raspberry Pis are an ideal solution to data backup, and can even be battery powered if you’re really roughing it for a few days.

ReMarkable Tablet Scores A MicroSD Slot

There’s been a marked trend towards modern tablets and phones having fewer expansion options. It’s becoming rarer to find a microSD slot available, which can be particularly frustrating. For [davisr], this simply wouldn’t do, and they set about hacking their ReMarkable tablet.

A rotary tool was used to make a tidy slot for the microSD card.

The ReMarkable already has a set of pads for an SDHC interface on the main board, ready to go. Despite this, both hardware and software modifications are required to get things up and running. [davisr] started by soldering some wires to the main board, feeding them to a microSD socket, which was mounted on the edge of the tablet in a convenient nook. The case was then delicately modified to make a slot for cards to be inserted and removed. With this done, the kernel was then recompiled to enable support for the SDHC interface, and everything was up and running.

With the modification in place, [davisr] now has over 150GB of storage available, which should last for quite some time. Similar hacks are possible on other platforms, too. Even the Pi Zero can mount a second SD card with the right mods!

 

Hackaday Podcast Ep14: Keeping Raspberry’s SD Card Alive, We Love MRRF, And How Hot Are Flip Chips?

Elliot Williams and Mike Szczys take a look at advances in photogrammetry (building 3D models out of many photographs from a regular camera), a delay pedal that’s both aesthetically and aurally pleasing, and the power of AI to identify garden slugs. Mike interviews Scotty Allen while walking the streets and stores of the Shenzhen Electronics markets. We delve into SD card problems with Raspberry Pi, putting industrial controls on your desk, building a Geiger counter for WiFi, and the sad truth about metal 3D printing.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (61.6 MB)

Places to follow Hackaday podcasts:

Continue reading “Hackaday Podcast Ep14: Keeping Raspberry’s SD Card Alive, We Love MRRF, And How Hot Are Flip Chips?”

Give Your Raspberry Pi SD Card A Break: Log To RAM

The fragility of SD cards is the weak link in the Raspberry Pi ecosystem. Most of us seem to have at least one Pi tucked away somewhere, running a Magic Mirror, driving security cameras, or even taking care of a media library. But chances are, that Pi is writing lots and lots of log files. Logging is good — it helps when tracking down issues — but uncontrolled logging can lead to problems down the road with the Pi’s SD card.

[Erich Styger] has a neat way to avoid SD card logging issues on Raspberry Pi, he calls it a solution to reduce “thrashing” of the SD card. The problem is that flash memory segments wear out after a fairly low number of erase cycles, and the SD card’s wear-leveling algorithm will eventually cordon off enough of the card to cause file system issues. His “Log2Ram” is a simple Unix shell script that sets up a mount point for logging in RAM rather than on the SD card.

The idea is that any application or service sending log entries to /var/log will actually be writing them to virtual log files, which won’t rack up any activity on the SD card. Every hour, a cron job sweeps the virtual logs out to the SD card, greatly reducing its wear. There’s still a chance to lose logging data before it’s swept to disk, but if you have relatively stable system it’s a small price to pay for the long-term health of a Pi that’s out of sight and out of mind.

One thing we really like about [Erich]’s project is that it’s a great example of shell scripting and Linux admin concepts. If you need more information on such things, check out [Al Williams’] Linux-Fu series. It goes back quite a way, so settle in for some good binge reading.

Pack Your SD Cards Swiss Army Style

SD cards have largely supplanted most other card-based storage devices, in all but a few niches. Available in standard, micro, and the rather obscure mini sizes, they’re used in everything from digital cameras to car stereos and console ROM carts. For most users, storing them consists of tossing them in a bag, occasionally in a plastic case that’s barely any bigger than the card itself for a little extra protection. This can get frustrating when carrying multiple cards, but [Dranoweb] has a solution.

[Dranoweb]’s design is similar to a Swiss Army knife, repurposed with many fingers, each with slots for holding everyone’s favourite storage devices. All the parts barring the screw are 3D printed. There are various designs of the storage fingers, allowing the build to be customized to suit varying quantities of SD and microSD cards. There’s even a deep-pocketed piece for USB drives and small adapters, and an oversized design for Nintendo DS carts.

It’s a tidy design that makes it that much less likely you’ll lose your microSD in the bottom of your backpack. Now, if you need to interface with an SD card, we can help you there too.

Set Up A Headless Raspberry Pi, All From Another Computer’s Command Line

There are differences between setting up a Raspberry Pi and installing an OS on any other computer, but one thing in common is that if you do enough of them, you seek to automate the process any way you can. That is the situation [Peter Lorenzen] found himself in, and his solution is a shell script to install and configure the Raspberry Pi for headless operation, with no need to connect either a keyboard or monitor in the process.

[Peter]’s tool is a script called rpido, and with it the process for setting up a new Raspberry Pi for headless operation is super streamlined. To set up a new Pi, all [Peter] needs to do is:

  1. Plug an SD card into his laptop (which happens to be running Ubuntu.)
  2. Run: rpido -w -h myhostname -s which downloads and installs the newest version of Raspbian lite, does some basic setup (such as setting the hostname), configures for headless operation, and launches a root shell.
  3. Use the root shell to do any further tweaks or checks (like launching raspi-config for additional changes.)
  4. Exit the shell, remove the SD card from his laptop, and install the card into the Raspberry Pi.

There are clear benefits to [Peter]’s script compared to stepping through a checklist of OS install and setup tasks, not to mention the advantage of not needing to plug in a keyboard and monitor. Part of the magic is that [Peter] is mounting the SD card’s filesystem in a chroot environment. Given the right tools, the ARM binaries intended for the Pi run on his (Intel) Ubuntu laptop. It’s far more convenient to make changes to the contents of the SD card in this way, before it goes to its new home in a Pi.

Not everything has to revolve around an SD card, however. [Jonathan Bennet] showed that it’s possible to run a Raspberry Pi without an SD card by using the PXE boot feature, allowing it to boot and load its file system from a server on the same network, instead of a memory card.