Dissecting a firmware image

dissecting-a-firmware-image

[Leland Flynn] did a great job of picking apart the firmware image for a Westell 9100EM FiOS router. Unfortunately he didn’t actually find the information he was looking for. But he’s not quite done poking around yet either. If you have never tried to make sense of an embedded Linux firmware image this serves as a great beginner’s example of how it’s done.

He was turned on to the project after port scanning his external IP and finding a random login prompt which he certainly didn’t set up. Some searching led him to believe this is some kind of back door for Verizon to push automatic firmware updates to his router. He figured why not see if he could yank the credentials and poke around inside of the machine?

He started by downloading the latest firmware upgrade. Running ‘hexdump’ and ‘strings’ gives him confirmation that the image is based on Linux. He’s then able to pick apart the package, getting at just the filesystem portion. His persistence takes him through extracting and decompressing three different filesystems. Even though he now has access to all of those files, broken symlinks meant a dead-end on his login search.

OpenSCAD is for use with 2D machine, not just 3D printing

openscad-for-2d-machining

Here’s an enclosure which was designed with OpenSCAD and cut out on a CNC router. [Matthew Venn] wrote about the project because he sees tons of 3D printing hacks that use the software, but almost never hears about it as a tool for laser cutting or CNC router/mill work. When we read that we thought we must have seen a lot of 2D hacks but a search of Hackaday’s previous offerings proved us wrong. Just this week we heard about the software in use with the Makerbot. Or you could go back about a year and read about creating 3D molds. But nothing on 2D work.

His post is a quick read and shows off the bare bones of the case designs he’s been working with for a few years. By referencing the code itself, and playing with how it changes the render in OpenSCAD he makes a strong case for quick and easy enclosure design. If you use this technique make sure to document your experience because we want to hear about it!

Adding a Bluetooth terminal to your router

bluetooth-router-terminal

This image shows an Android tablet monitoring the terminal of a router via Bluetooth. It makes it a snap to tweak your router from a multitude of devices as long as you’re within range (usually BT works up to about 30 feet or so). The only part that [Yohanes] needed to pull off the hack was a Bluetooth module which he picked up for a few dollars.

All routers will have serial connections somewhere on the board. His model (Asus RT-N16) even had the GND, RX, TX, and VCC pads labeled. He soldered a SIL pin socket to the port which accepts the pin header from the Bluetooth module. Before plugging that in he had to issue a few commands to the device to get it using the same baud rate and settings as the router’s serial port. With that taken care of he can now wirelessly monitor and control the device via the serial terminal.

The one issue which he did encounter is that the module is slower to boot than the router. This means that at power-up you will not see anything on the terminal until the router has already started to load the Linux kernel. If you don’t plan on doing any bootloader hacks this shouldn’t make any difference.

Turning a tiny router into a webradio

tplink

While the hacking zeitgeist is focused nearly entirely on all those new ARM dev boards that include the Raspberry Pi, some people out there are still doing it old school by modifying existing electronics to suit their needs. [Peter] picked up one of those very inexpensive TP-Link 703n wireless routers we’ve seen before and modified it into a standalone web radio, complete with volume and tuner knobs.

The TP-Link 703n is a wireless router smaller than a credit card available from the usual Chinese resellers for about $20. Able to run OpenWRT, this very inexpensive piece of hardware can be transformed into a device comparable to the Raspberry Pi; a complete Linux system with a few GPIO pins.

[Peter] took his 703n router and added an ATtiny85 connected to two pots and the internal UART. This, along with a script to read the values from the pots, tells the router what station to tune into and what volume to play it. The audio is handled by a USB soundcard with an internal speaker, making [Peter]’s build one of the smallest purpose-built Internet radios we’ve seen.

You can see [Peter]’s radio in action after the break.

Continue reading “Turning a tiny router into a webradio”

Router jig for a perfect circle

router-jig-for-cutting-circles

We once enlisted a contractor to cut a plywood circle for a cat condo we were building. Now we’re embarrassed that we couldn’t come up with a solution as eloquent and easy to use as this circle cutting router jig which [Grays42] built.

He’s using a small trim router for the job. The jig is made up of two thick-walled pieces of PVC pipe. We don’t think the router is attached to jig. Instead you hold it against the wooden spacer which is on the outside edge of the cut. He doesn’t mention how he made the spacers, but we’d recommend cutting a hole the size of the pipes and then ripping down the middle to remove some of the material (tape the two spacers together during fabrication to ensure proper alignment). It just takes some nuts and bolts from the hardware store to assemble everything.

[Grays42] is using this to cut rings for his telescope build. We have our eye on it for making our own wooden Bulbdial clock.

[via Reddit]

Outlet charging station retrofitted with the guts of a WiFi router

While wandering around the aisles of his local electronics store this Westinghouse USB charging station caught [James’] eye. He sized it up and realized it would make the perfect enclosure for a small WiFi router. And so began his project to turn a TP-Link TL-WR703N into a DIY Pwn Plug.

The basic idea is to include hidden capabilities in an otherwise normal-looking device. For instance, take a look at this ridiculously overpriced power strip that also happens to spy on your activities. It doesn’t sound like [James] has any black hat activities planned, but just wanted an interesting application for the router.

He removed the original circuit board from the charging station to make room for his own internals. He inserted a cellphone charger to power the router, then desoldered the USB ports and RJ-45 connector for the circuit board to be positioned in the openings of the case. He even included a headphone jack that breaks out the serial port. There’s a lot of new stuff packed into there, but all of the original features of the charging station remain intact.

LED wand brings ergonomics to light painting

Quit struggling with hastily patched together electronics for your light painting images. Follow [Madox’s] example and build a light painting wand designed with your hand in mind.

You wield it much like a sword, but the only damage it does is to the long-exposure camera pointed its way. The RGB LED strip is controlled by the guts of a tiny little wireless router, a TP-Link TL-WR703N. This lets [Madox] connect using an Android device to upload different images. It also lets you tweak the settings like adjusting the timing between columns to match your exposure settings. The custom handle design provides a home and mounting plan for everything involved. It was 3D printed at the Sydney Hackerspace.

This isn’t the first light painting device running Linux. We’ve actually seen the Raspberry Pi used in much the same way but that final project involved using an entire recumbent tricycle to move the colored lights.