Rather than work from the web interface and user scripts down, [Dmitry] decided to start from Transcend’s GPL package and work his way up. Unfortunately, he found that the package was woefully incomplete – putting the card firmly into the “violates GPL” category. Undaunted, [Dmitry] fired off some emails to the support staff and soldiered on.
It turns out the card uses u-boot to expand the kernel and basic file system into a ramdisk. Unfortunately the size is limited to 3MB. The limit is hard-coded into u-boot, the sources of which transcend didn’t include in the GPL package.
[Dmitry] was able to create his own binary image within the 3MB limit and load it on the card. He discovered a few very interesting (and scary) things. The flash file system must be formatted FAT32, or the controller will become very upset. The 16 (or 32)GB of flash is also mounted read/write to TWO operating systems. Linux on the SD card, and whatever host system the card happens to be plugged in to. This is dangerous to say the least. Any write to the flash could cause a collision leading to lost data – or even a completely corrupt file system. Continue reading “Advanced Transcend WiFi SD Hacking: Custom Kernels, X, and Firefox”→
[Pablo] is a recent and proud owner of a Transcend WiFi SD Card. It allows him to transfer his pictures to any WiFi-enabled device in a matter of seconds.
As he suspected that some kind of Linux was running on it, he began to see if he could get a root access on it… and succeeded.
His clear and detailed write-up begins with explaining how a simple trick allowed him to browse through the card’s file system, which (as he guessed correctly) is running busybox. From there he was able to see if any of the poorly written Perl scripts had security holes… and got more than he bargained for.
He first thought he had found a way to make the embedded Linux launch user provided scripts and execute commands by making a special HTTP POST request… which failed due to a small technicality. His second attempt was a success: [Pablo] found that the user set password is directly entered in a Linux shell command. Therefore, the password “admin; echo haxx > /tmp/hi.txt #” could create a hi.txt text file.
From there things got easy. He just had to make the card download another busybox to use all the commands that were originally disabled in the card’s Linux. In the end he got the card to connect a bash to his computer so he could launch every command he wanted.
As it was not enough, [Pablo] even discovered an easy way to find the current password of the card. Talk about security…
[Seth King] wasn’t satisfied with current robotics platforms that don’t work well outdoors. He started the Open Rover Kickstarter with the end goal of having a 6-wheel robot with a rocker-bogie suspension just like the Mars landers. We’re sure it’ll be an interesting platform.
This is a video of [Elliott] using his autocrack script to crack a WEP wi-fi network. It took [Elliott] less than a minute to crack a network he set up. Lesson: don’t use WEP.
Adding wi-fi to a laptop the fast way
This laptop used to have a broken Mini-PCIe wi-fi adapter. [Mikko] fixed the wireless by taking out the old card and hooking up a USB wi-fi adapter. He soldered the USB leads directly to the back of an internal USB port and used hot glue “to prevent bad things from happening.” A very easy, fast, and cheap way of fixing a broken wireless adapter.
The WiFi uploading Eye-Fi SD card made a big splash when it was first introduced, but now Eye-Fi has a whole line of different products. The top of the line is the Eye-Fi Explore, which supports geotagging without using a GPS. Instead of GPS hardware, it uses the Skyhook Wireless Wi-Fi Postitioning System, which correlates the position of the Eye-Fi’s access point to GPS locations, creating virtual GPS functionality. This allows photos taken with the Eye-Fi to be be geotagged. Of course, the accuracy of the system is noticeably lower than true GPS and seems to be affected by a number of external factors, but it is still accurate enough to tag the photo within the immediate vicinity of where it was taken.
WiFi positioning is great feature, but certainly not limited to photography. Since the Eye-Fi is at its core SD storage media, you could probably have it geotag data saved to the card, even if it wasn’t created by a digital camera..
You may have already heard that Chrysler is planning to provide in-car wireless internet access to its vehicles. If not, expect to hear more about it later this year when the requisite hardware becomes a sales-floor option, or next year when it becomes factory standard for some cars.
We can’t say it’s a bad idea, it’s just not a new one. Plenty of commercial portable routers are available, but they still need a modem and data plan to provide internet access. For internet access and wireless routing, look to [Nate True]’s cellphone-router combo, which uses a spare Nokia cellphone and a highly modded Wi-Fi router running OpenWRT. [True] has made it easy by providing the instructions and necessary custom code, but it seems like a lot of effort for a relatively slow connection. We think the original Stompbox is still the most fun since it has the speed of commercial devices and an open x86 OS to modify.
A wry editorial on Time Magazine’s site about tapping into your neighbors’ Wi-Fi tells of how the author [Lev Grossman] stole internet access from his neighbors’ open networks for years. He finally decided to pay for his own connection, which he fittingly leaves on an open network. He makes the point that leaving it open is a violation of his TOS agreement, but he doesn’t seem particularly bothered by the notion of people tapping into his network.
[Bruce Schneier] takes an even stronger stance on the issue, suggesting that it is not only safe to leave your network open, but a matter of politeness toward your guests, similar to providing them with basic amenities. He also mentions that if your computers are not adequately secured, network security won’t make much of a difference. We tend to agree with [Schneier] on this: we also leave our network completely open.
That’s not to say [Grossman] doesn’t have a point about the unreliability of pilfered internet access, noting “I always seemed to lose connectivity just when I was about to send a crucial e-mail.” Sure, we leave our network open, but we have to pay for our internet access. We really can’t afford not to. One thing [Grossman] didn’t mention (neither did [Schneier], but he wrote his article before this happened), is that a Maryland bill that would criminalize leeching Wi-Fi has been shot down. The first legislation of its kind, the defeat of the bill mean citizens of Maryland are free to leech from open networks without fear of prosecution, but it sets a precedent that may influence future rulings.