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USB "Condom" Allows You To Practice Safe Charging
MojoKid writes "Yep, a USB condom. That term is mostly a dose of marketing brilliance, which is to say that grabs your attention while also serving as an apt description of the product. A little company called int3.cc has developed a product—a USB condom—that blocks the data pins in your USB device while leaving the power pins free. Thus, any time you need to plug a device such as a smartphones into a USB port to charge it—let's say at a public charging kiosk or a coworker's computer--you don't have to worry about compromising any data or contracting some nasty malware. It's one of those simple solutions that seems so obvious once someone came up with it."
My MP3 player, the nearly 10 years old Cowon D2, actually came with a power-only USB cable. Maybe their goal was to save money on copper.
Plugging in the phone would still make it vulnerable to side-channel attacks where voltage fluctuations are monitored. Also, unless you're watching the phone, someone could unplug the condom and plug it in directly in order to compromise it. I'm sure a pwning kiosk operator could come up with some excuse.
All I have to do is feed some "connection error" kinda stuff on the screen until the guy takes off his condom.
Webmasters already do this to me all the time when they want me to enable JavaScript on my machine.
Desperate people needing to get some juice into their phone will do whatever the machine says in order to get what they want.
Its hard to deal with "typhoid Mary's" as long as Congress keeps creating all sorts of anti-reverse-engineering laws which the dispensers of bad code hide behind.
This wouldn't allow devices to detect fast charge capability, as that depends on resistances between data pins and power pins, or high-level protocol negotiation if it's an intelligent host with this capability. Devices will only charge slowly (100mA) if at all.
Damn... I wanted something that would take all kinds of measurements and then later plug into my usb port.That would be real marketing brilliance. Speed, power, duration, ect. correlated with attractiveness.. that sounds like some useful data.
I've made my own, but you can buy them inexpensively. They're really convenient if you're, say, trying to keep devices from popping the VMWare Fusion Mac/Linux selection dialog or complaining about ejection.
So, yeah, this guy made a board, but a cut-line extension cable has been the answer to this problem for a while. Some devices may fuss or trickle charge, but it generally works.
This over-engineered nonsense in the article is ridiculous.
Why does this require a big PCB with three ICs? Why not just simply remove pins 2 & 3?
After all, we've had power extensions for years!
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
I've apparently made 'USB condoms' myself. A male and female usb connector soldered end-to-end, the data pins shorted together.
This enables my ancient HTC Desire to recognize any usb charger as a dedicated charger, and charge with up to 1 A (in reality significantly less). It is a low tech solution that works.
So why so much electronics on the board??
Safety from infection is nice, but the burning question on everyone's mind is: how effective are these at preventing unwanted cyber-pregnancies?
A little company called int3.cc has developed a product—a USB condom—that blocks the data pins in your USB device while leaving the power pins free.
If you consider something that blocks the middle of the male end but leaves the sides open to be a "condom," you might want to see a doctor. Soon.
In the standard A and B plugs the data pins are recessed compared to the power pins. Grab any standard cable and you can slide it in until the power makes contact, giving you charging without any data connection.
I've been doing this for years to charge a MP3 device without it being mounted by the host computer.
see
Could inductive chargers be considered a diaphragm?
There's a current KickStarter project called LockedUSB which does something similar, but which also includes a power management chip in order to negotiate higher power charging levels that normally require data connectivity. LockedUSB doesn't appear as big or ugly as the one in TFA. (Full disclosure: I'm a backer)
Always practice Safe Hex
I can't believe nobody has posted that yet...
...so that it doesn't automatically execute/autoplay/file-connect/whatever when the hardware is plugged in?
I'm not repeating myself
I'm an X window user; I'm an ex-Windows user
I have a USB extension cable that for some reason does this. It came with a one of those old all-in-one multi-type card reader I picked up in 2007. It took me hours to figure out why I couldn't read my external hard drives while using the extension cable. For the first hour I thought the drive wasn't receiving enough power (it was). It wasn't until I used the extension to charge my ipod that I realized what was going on, was that it was blocking data.
No documentation on the cable but I have to assume it wasn't a manufacturing defect, given they supplied two extension cables, and only one of them has this feature.
When I first got a Playstation Vita (What? Why is everyone laughing?), I had a USB battery to charge it on the go - but it wouldn't work! Of course, Sony said that it would only charge from their own Vita power bricks, but that was obviously just PR - it was just a USB A connector on the business end, after all. After some investigating, I found out that the Vita checks for shorted data pins, and if it doesn't find them, it won't charge (unless it's connected to a PS3 or computer.) Other products use different methods, such as sets of resistors to put a certain constant voltage on the data pins; said voltage varies according to how much current the adapter can safely provide. Apple is a big one for this method. The solution I went with involved getting some USB swivel adapters, cutting open the female sides, and soldering the data pins together. This tricked the Vita into thinking it was connected to its own power brick, so it drew the full 1.5A from any USB source. This could be dangerous, if you have it on a cheap charger that can't safely provide that much. Since then, I've used these devices for charging other things that use the same method of identifying fast chargers, and even for data safeguarding, as this article suggests. If you don't want to do the work yourself, such things can easily be purchased (they weren't as prevalent at the time). -- As several other people have said, I'm curious what all the intermediate stuff in this USB Condom is for. Perhaps it's to do with negotiating higher power draw from host devices, and making your device think it can pull however much it wants, for safe, fast charging? -- Sources: http://www.dannychoo.com/en/post/26419/PS+Vita+USB+Mod.html http://www.amazon.com/dp/B007Y3L5RI
We need more hexadecimal top domain levels.
They're trying to sell something that does the same as this for a lot more? Awesome.
A capacitor connected between D+ and D- lines will block any USB negotiation and data transfer without interferring with the DC levels used to "negotiate" charger capacity.
From the "Same same, but (very) different" Dept. there is this little Kickstarter project:
http://www.kickstarter.com/projects/david-toledo/the-practical-meter-know-your-power
Actually, it is twofold, there's the "Practical meter", which shows how much power is drawn, and then there's the three tipped charging cable with built in circuits enabling a device to draw more power from sources that supports it.
USB Condom ? Is this from the Science fiction series by Jeffrey A. Carver about Star Spanners and Robots that invent the Condom Protocol of Safe Communication ???
Somebody must have dozed off reading too much Sci-fi stories.
Hmm, if that's a USB condom, then I guess some of my devices came with a USB ePeen enlargement.
I can't remember which ones that came with the "changing only" cable, anyhow, I also remember some of them wanting to change more for a "data cable".
I'm pretty sure one was my Garmin GPS device. It will not charge without the cable it came with: The "charging" cable has a resistor from a voltage line to one of the data lines, and refuses to charge without it (even when connected to a PC and transferring data). When I hook that "charging" cable up to another powerpins-only extension cable it doesn't charge (no data pin resistor), so I'm guessing a USB condom wouldn't work on it either.
The point is: This may not work with all devices. BTW, I vowed not to buy Garmin products anymore thanks to the headache their cabling BS has caused.
I've built workstations intended for connection to library systems, and one of the airgap security measures I've employed was to cut the data conductors behind the USB port*. OK, it's permanent unless you're really handy with a soldering iron, but you'd have to get around the keybolts holding the case together first...
*Recent innovations in workstation motherboard design have done away with PS/2 ports for keyboard/mouse, the way around that is to use a quality keyboard/mouse and hardwire those suckers.
And trust that the user isn't about to alligator the data lines on one of those...
Operation Guillotine is in effect.
There's plenty of those batteries which you plug into a USB port to charge, and they don't have data pins. So if you plug the device you want to charge into the output of the battery you don't run any risk.
Thus, any time you need to plug a device such as a smartphones into a USB port to charge itâ"let's say at a public charging kiosk or a coworker's computer
Unless one is standing right there, what is to prevent someone from removing the "condom", plugging the bare cable in, slurping all one's data off, then putting the "condom"?
There is no "-1 offended" or "-1 you don't agree with me" mod options for a reason.
I've been in airports, and had people w/ just a USB cable ask me if they could plug into my laptop to charge ...
Luckily, as I usually fly southwest, the two times it's happened I was able to point out that there was USB charging available from their power points.
(when people think I'm mean for not sharing power in other situations, I'll break out the 'It's not how many USB sticks you plug into your laptop' PSA reference) ... I'd love for USB sticks to bring back the hardware write-only switch.
Personally, I wouldn't need one of these 'til my current phone dies -- WebOS will assume charging only unless you specifically enter your passcode to allow it to function as a USB disk when you plug it in.
Build it, and they will come^Hplain.
Oh so this isn't another tracking device for fitbit, endomondo, Disappointing.
BLACKBERRY Battery Charger Bundle fuer Z10
The charger allows daisy-chain connection for the phone (or any other micro USB device). I have learned that it effectively works like the "usb condom". Additional feature is that it shields the phone from the charging device, not only a computer. This allows for the use of dumb chargers. Otherwise the phone (BB Z10) gets too smart and only draws 500mA where the charger is actually capable of 2A.
Blackberry is not doing too well now as a company, but I still like them for the hardware and those small niceties like cheap but durable accessories. The headset for BB9700 costed 3 Euro and was of great quality. But I digress.
...a stunned silence fell upon the hall.
Blocking the data pins means it will not charge at anything more than the 100ma trickle. you NEED the resistance devider on the data pins to tell the phone/tablet that it is a high current charger and kick it into high gear.
Note: you have been able to buy a $1.99 device like this that DOES enable high power charging for well over 4 years now. IT's an iphone USB charger adapter adapter. little usb plug or 6 inch cable that adds the resistor network to fool the phone to charge at full speed.
Nothing new here, the product has existed in a better form for years now.
Do not look at laser with remaining good eye.
The moment I plugged it into my laptop, even before plugging the iPhone in, the laptop turned off. No damage. Being naturally curious I tried it again and it was repeatable.
Sounds like you are a scientist. Congratulations!
My N900 requires confirmation on the screen to grant data access to USB host devices, so this thing isn't useful for it or any device which has this important feature (like even a Blackberry). What it will do is prevent the charging power from being negotiated.
"When information is power, privacy is freedom" - Jah-Wren Ryel
I am sure there are situations where someone might need to plug in their phone in a random place for that important call, but I mean, someone leaving their home with a 1/4 charged phone before heading out on a business trip is probably going to forget their condoms too.
No glove, no love, period.
I haven't thought of anything clever to put here, but then again most of you haven't either.
Why do these solutions need to be soo complex?
Corner cases usually. The power requirements of devices plugged into USB are a bit unpredictable so it's more complex than many realize. I agree with you though. It seems like they are adding a bunch of needless complexity to make up for some poor initial design choices.
As an example of poor design choices, it has always mystified me why they made USB a keyed connection instead of a reversible one. I'm not overly impressed with Lightning cables from Apple but one of the things Apple did right was to make it so you didn't have to fuss with worrying about which way was "up". There is no reason USB could not have been designed so that you didn't have to worry about orientation when plugging it in. It's got 4 conductors (5 in some cases) so it wouldn't exactly be rocket surgery to put enough brains into the controllers to negotiate the connection. They could have also solved it with a better designed (albeit more $) connector. Hell if they were really lazy they could have even done it by adding more wires. But instead they chose the cheapest possible route and pretend that putting the USB logo on one side of the connector somehow makes obvious (it doesn't) which way to plug it in.
A USB "charging" cable has the data pins shorted internally to allow high-current charging to USB devices. Why not just use one of these as it will not allow data transmission?
"It's one of those simple solutions that seems so obvious once someone came up with it"
Also it already exists and I've had one for years. It's called a "power-only" USB cable. There are many manufacturers of them in the world.
Because picking up a used condom off the ground for re-use carries no negative connotations whatsoever.
The new iOS will ask you if you want to 'trust' the host you're connecting to on connection, in theory, no condom is needed.
Make jokes as (in)appropriately as possible.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
So now the arms race escalates to USB ports that cut holes in the USB Condom so the contacts work again, and they can go back to sucking down all your data.
I like music
Their domain int3.cc is an allusion to the one-byte software interrupt instruction on 16-bit x86 systems. Opcode 0xCC disassembles to int 3, and it's most frequently used by debuggers, which patch a single byte of code with it to make a breakpoint.
Qu'on me donne six lignes écrites de la main du plus honnête homme, j'y trouverai de quoi le faire pendre.
This won't work for devices that insist on using the USB charger protocol to negotiate higher currents from the power supply. For those that will still work without the data pins present you'll be charging much slower with the 500mA default limit.
I am becoming gerund, destroyer of verbs.
would a charger need to current limit the power if the device tries to draw more than it can provide?
Because many chargers are connected to devices or power lines (110VAC etc) that can supply MUCH more power than the cable can handle. The wires inside a USB cable used for power are often 24 gauge which can only handle a relatively modest amount of power before they overheat. You need a charger that is smart enough to not exceed the limits of a USB cable even if the device is dumb enough to "request" that much power. Otherwise you could end up with a molten wire rather easily.
- Part way through the cable, carefully cut into and remove the cable jacket. Push the shield conductor aside.
- Leave the black (ground) and red (+5V) wires where they are.
- Cut the green and white wires.
- On the "phone side" of the cable, strip and solder the green/white wires together. Try to make a clean "blob" joint without any pointy bits that may stab the neighboring wires and cause a short.
- On the computer/charger side, cut the green/white wires back to two different lengths so they don't touch each other, or touch the joint you just made.
- Insulate the 4 wires in a couple layers of electrical tape.
- Wrap the whole cable, including the shield, in more electrical tape.
This isn't 100% correct to the USB spec - your phone might try to pull 1A from a USB port or charger that can't supply it. But for the vast majority of situations (charging your phone off a USB port on a desktop PC, or using an iPad charger or something) it'll work just fine.
And that's apparently not even a requirement, because I have a WD USB drive that helpfully puts the WD logo on the side you're supposed to have up and the USB logo on the side which is down - exactly the opposite of the "standard" way USB cables are "supposed" to work.
On some devices it's not actually clear which way "up" is supposed to be. I'm typing this on a tower PC. It has a bunch of vertically oriented USB ports on the back because the motherboard doesn't know what kind of case it will be placed into. The only way to know what "up" is, is to figure out which wall the motherboard is mounted to. That means "up" is actually "right" or "left". It's faster to just try one direction and if it doesn't go in, flip it. Of course it seems the first way way you try it invariably is the wrong way. You'd think I'd get it right around 50% of the time but it never seems that way.
Been waiting to use that one....
A USB condom is a good idea. What I'd like to see is a split usb charger cable for vehicles where the USB cable that connects to the stereo powers down when the vehicle does. I had to make one myself that had 2 male ends and 1 female end so that I could connect one to the stereo USB input to control the device and the other end was plugged into a 12V to USB adapter on a port that I hotwired to always stay powered. How else am I supposed to keep my iPod charged? Without this cable as soon as I turn the car off the iPod begins to discharge till it dies. With a prefab cable there are diodes built in that switch power sources but I found them to be unreliable which often caused the iPod to freak out and the cable to fail to switch sources. The only answer I found was strip the cable and just solder them together so that the power flow was seamless.
Mind if I just plug this dodgy looking device in to your computer to charge my phone? It's just that I don't trust you. Should go down well.
Hey that's no fair, I disclosed this idea to IBM for patent last year. Furthermore, if your device needs less than 100ma, you can simply use a clip to cover the data pins. You can make it out of a pop can for free. Also you could snip the data wires on a USB extension cable. For high power devices all you need to do is splice in something to negotiate current with the host controller.
The USB cable I have on my desk with the data pins cut... so my stupid Aiptek camera stops going into "data" mode when connected.
(Now if I could figure out what Magic(tm) is in the pulg that allows the AC adapter to power it while on...)
Put a capacitor across the data lines. For good measure, put a capacitor across every pair of lines for a total of six; this also protects from some forms of plain old electrical damage. Alternately, use inductors interrupting the conductors.
I like LockedUSB Adapter, it seen like a much better product. It regulates its power, ESD protected and have a nice enclosure. LockedUSB already reached it funding over kickstarter http://www.kickstarter.com/projects/1137339450/lockedusb-adapter-usb-charger-firewall-and-power-o