16 ms·

USB Condoms

376 points by lukashed 13y ago

Piskvorrr 13y ago
Even easier, although not as nice-looking: get a common off-the shelf USB Y-cable, plug the power-only male into computer, plug phone into female outlet; done. See e.g. http://easyshop.kiev.ua/images/shnuri/shnuri/Usb-y-power-cable.jpg http://easyshop.kiev.ua/images/shnuri/shnuri/Usb-y-power-cab... for an illustration what the cable looks like. (I have been doing this to charge my phone, as even the USB mount dialog confuses some apps)
- aestra 13y ago
  Dead link.
  - StavrosK 13y ago
    Works for me. It's the cable most portable/USB hard disks come with.
  - Piskvorrr 13y ago
    Hmm, weird. Just try searching for "USB Y Cable" images, lots of results like these will pop up: http://www.everythingusb.com/images/list/apricorn-aegis-bio-usb-cable.jpg http://www.everythingusb.com/images/list/apricorn-aegis-bio-... Basically, it's a USB extender cable, with an extra pair of power wires soldered on and terminated in a USB male header - the original use is for power-hungry disks, where you'd plug both the male headers into the computer, increasing the available power (as USB 2.0 can only give 500 mA through a single port, per spec), at the cost of hogging two USB ports. It can be re-used as a USB condom as well.
- lnanek2 13y ago
  There are actually charging only USB cables out there as well. Heck, I suspect the cable that came with the Chromecast is one, just to save money on data lines that would never be used.
- dnautics 13y ago
  but why buy another cable, with all the fumbling and whoops I used the wrong cable, when you can buy something that you permanently "by default" keep on the end of the cable that you already have, and take off when you're ready to use the cable for serious.
c-oreills 13y ago
The sales page [1] has a bit more info on what these actually do. [1] http://int3.cc/collections/frontpage/products/usbcondoms http://int3.cc/collections/frontpage/products/usbcondoms
- nyrina 13y ago
  Is it just me or is this a bit.. Over the top? I've never put my phone into something to charge and thought "Hey, they might steal my data".
  - nraynaud 13y ago
    you should
  - myhf 13y ago
    Sounds like it would be pretty easy to steal your data.
  - nodata 13y ago
    If you are into unprotected charging, then that's up to you.
  - dylangs1030 13y ago
    It's actually very serious. Just like ATMs, power stations can look completely harmless while being incredibly dangerous under the surface. Once you connect to a system via USB, it automatically allows data transfer, which makes your smartphone vulnerable to malware and data theft. I can't speak for Android, but iOS 7 now has an automatic warning when you connect to new devices that asks if it should be trusted, presumably to mitigate this risk. However, I doubt anything less than a full hardware solution can actually eliminate the risk entirely. There's a reason why conferences like DefCon warn you explicitly not to use power stations or ATMs nearby - they can be hijacked very easily.
    - Piskvorrr 13y ago
      Well, you should assume that everything out there would be malicious, and work from _that_; if you go to DefCon specifically, this is a reasonable expectation. New-ish Androids pop up a "USB connected, do you want to use this" prompt as well; but many devices (esp. embedded ones) don't.
deleted 13y ago
[deleted]
willvarfar 13y ago
Recently, it comes to light that those handling the Snowden files are using air-gapped computers and passing encrypted data to the outside world via ... USB sticks. Can't USB sticks execute arbitrary code? Couldn't an attacker infiltrate the publically accessible computers that these people use and put a data-stealing trojan onto USB sticks used to bridge the air-gap? Do other media that most computers accept these days e.g. sd cards support arbitrary code execution too? How can you get around this? EDIT: it was DMA attacks that I was thinking off, and USB seems free of them at least. I guess, if you trust the robustness of your USB stack against exploit, that USB is a fairly safe bet. As these very people are reading the NSA secrets, one wonders what'd happen if they discovered some hint that that NSA could do precisely that - exploit via USB plugging in.
- kirab 13y ago
  It was an old Windows problem that it automatically executed code on mounted media devices. But I hope this was fixed on Windows in the meantime and other OS don’t have this problem.
  - guard-of-terra 13y ago
    It's deeper than that. You're plugging a device into your system's bus, the attack surface is huge for that device to steal or modify your data. USB device is a very different beast than CD.
- maggit 13y ago
  A USB stick could be anything, but if it is simply a proper USB mass storage device, it, by itself, can not execute code on the host machine. To execute code on the host machine, either the host machine has to be stupid (like many Windows versions that try to automatically execute code from plugged-in devices without user interaction) or the device has to be malicious, trying to exploit weaknesses in the host machine. ---- Now, for the files being put on these sticks, there are probably many opportunities to inject a trojan.
- nodata 13y ago
  Your "usb stick" could be a usb keyboard which changes your password and sets a new one, even sending the data over a 3g connection to an adversary.
nraynaud 13y ago
is it me or this thing is huge ?
StavrosK 13y ago
Can't you achieve the same thing with a cable whose data lines just aren't connected to the jack? Why do you need a whole circuit?
- seclorum 13y ago
  Because you don't know that you can just cut the data wires in a cheap USB cable, and want to be 'protected' by a cool hipster toy that'll sit in your laptop/phone baggie until you're at some party and can shout in triump when someone plugs in their phone 'just to charge': "NO, USE MY USB CONDOM!!" EDIT: if this thing actually had some diagnostic LED's that would show you that the 'power port' was trying to do something nefarious on the data lines, it'd be a lot more useful than an ultra-cheap snipped cable imho ..
- morsch 13y ago
  Sure. The advantage of this is you don't have to cut open one of your cables, you can easily (and visibly) decide whether you want the data pins connected or not and this works for any USB device, ie. USB micro as well as Apple and other proprietary connectors.
  - icebraining 13y ago
    you can easily (and visibly) decide whether you want the data pins connected or not You could just get two cables, and only patch one. this works for any USB device So would the cable option if you used a male / female cable instead of a male / male one.
  - bho 13y ago
    actually I think you can just stick some electrical tape over the data pins in a standard USB cable. not sure how this device does anything different.
- delgaudm 13y ago
  There is a ready made charge only cable from Mediabridge. Amazon: "Mediabridge USB Charging Cable - (6 Feet) - USB-A Male to Micro-B Charging Cable"
Egregore 13y ago
There are external batteries for phones, when you charge through them I think no data will be lost.
- rbanffy 13y ago
  As long as you trust your external battery
jablan 13y ago
At first I thought it was a device which would prevent an infected computer from writing malware to the inserted flash drive, as a hardware antivirus.
- deleted 13y ago
  [deleted]
smoyer 13y ago
It might be a bit smaller, but the concept has been around a long time (I use my external hard-drive's cable): http://www.amazon.com/s?ie=UTF8&page=1&rh=i%3Aaps%2Ck%3Acharge%20only%20usb%20cable http://www.amazon.com/s?ie=UTF8&page=1&rh=i%3Aaps%2Ck%3Achar...
hwh 13y ago
For those who didn't click through everything: This devices is an adapter that cuts the data lines for a USB connection. Such a device will most probably restrict the device (if it properly implements charging) to a maximum charging current of 100mA. The data lines are used for identifying the maximum current allowed.
- Kliment 13y ago
  You can stick a resistor on the data lines to pretend to be a high-power charger.
  - hwh 13y ago
    Or implement other identification mechanisms that exist or might evolve. Yes. But in the same run, that might take too much from the port you plug it in mistakingly. If you don't trust the port, you will often not even know what it is. It's probably safe to assume it will indeed give you 500mA (when it's in the device or a powered hub). What about the 1500mA ones? That said, if one desperately needs to charge a battery, one is likely to take even 100mA. Cutting two lines of a cable doesn't seem that hard and ugly compared to a un-encased PCB, though.
    - Kliment 13y ago
      What? A patched-together table is much uglier than a bare PCB, particularly with nice layout.
      - michaelt 13y ago
        Depends if your use case involves coming into contact with anything conductive.
    - deleted 13y ago
      [deleted]
- yungchin 13y ago
  According to these guys, if the data lines are shorted according to the "dumb usb" spec, you should be able to draw whatever the port can provide: http://www.portablepowersupplies.co.uk/portapow-fast-charge-micro-usb-cable/ http://www.portablepowersupplies.co.uk/portapow-fast-charge-...
Jugurtha 13y ago
Well, like everything else .. Marketers are betting on the laziness of people. Why tell someone he can lose weight by working out and eating less, when you can sell them a pill that makes them lose weight while they sleep and get abs in 7 minutes? Why learn programming in several years, when you can "learn programming in three days". Why tell people to be cautious with their data, not to click on everything, when you can sell them a "condom" that enables them to remain reckless and careless and lazy ?
- rbanffy 13y ago
  You can also just cut wires 2 and 3 of your cable.
- Piskvorrr 13y ago
  Some attacks do not depend on user interaction ("clicking"); plugging the device in might be sufficient. Thus, hardware air-gap becomes necessary. (of course, this just shifts the problem around: now you need to trust the "usb condom"; but given its simplicity, it should be much harder to put anything nefarious there)
  - Jugurtha 13y ago
    Yeah. I looked at it from a "consumer education" perspective, but it is unrealistic to ask for that. Not everyone is interested in those things. However, what does that thing actually do ? How does it work? Signatures ? Block "autorun" or something ? I didn't see any details.
    - Piskvorrr 13y ago
      The USB condom? Much lower-level than that: no data pins, only power.
the_mitsuhiko 13y ago
Does anyone know how the voltage negotiation works for those?
- Piskvorrr 13y ago
  It doesn't - therefore, a to-spec USB2.0 host should not give more than 100mA over the condom, but good luck finding such a beast (most hosts will happily serve 500 mA w/o negotiation).
  - hwh 13y ago
    Nitpick: It's current negotiation, not voltage negotiation. As for voltage - 5V is universal with USB. And as for current - I wrote about the matter in another reply to the OP: The problem will be a well-behaved USB device simply won't take more than 100mA. I.e. it will use the "flat" charging curve, even if the host could deliver more.
    - SEMW 13y ago
      > As for voltage - 5V is universal with USB Nitpick for interest's sake: apparently there's a new (2012) 'USB Power Delivery' spec[1] which specifies two new voltage levels (12V & 20V) in addition to 5V, with higher current limits (2A at 5V, 3A at 12V or 20V for microUSB connectors). Obviously both ends (and the cable) have to support it; I don't know if anything actually does yet. [1] http://www.usb.org/developers/powerdelivery/ http://www.usb.org/developers/powerdelivery/
    - Piskvorrr 13y ago
      Pedantry: That should be obvious from the units, wouldn't it? (Volts for voltage, amperes for current, ohms for resistance) I do agree that the general public uses these interchangeably, bringing confusion :) As for a well-behaved device - there aren't very many of those, either. Fortunately, this is less of a problem with USB3 - more devices follow the spec closely.
oemera 13y ago
It could be way more popular if these wouldn't be called 'condoms'. Some people can get offended and wont buy it even if it would be useful. Just my 2 cents.
- kawsper 13y ago
  Why would someone be offended by the word "condom" ?
- sdfjkl 13y ago
  USB prophylactics?
  - joezydeco 13y ago
    USB Data Isolator.
- mbarrett 13y ago
  the USB Condoms nomenclature is likely the reason it is getting exposure. For a first run, I'd say it was definitely successful considering its sold out. But you're right, retail would probably suggest a name change.
auggierose 13y ago
"If you're going to run around plugging your phone into strange USB ports, at least be safe about it. ;-)" Exactly. Better safe than sorry.
lechevalierd3on 13y ago
The all NSA scandal is a quite sad revelation, but there a re so many business idea to built off it.
contingencies 13y ago
When I feel my batteries are low, I like to get my juice flowing by plugging in to the nearest socket available. Sometimes, I even get a surface to sleep on, and when that happens, often I get to load up on media. Sometimes when the media's done there's some funny business. Occasionally, I even get a special powerup for breakfast. There's nothing like waking up in the morning after a new encounter, wealthier for the memories, fully charged and ready to go. - Anonymous mobile device, 50 Bistreams of "Hey!"
Fuxy 13y ago
Yay! I don't have to build this anymore.
gametheoretic 13y ago
>"Any port in a storm." as the saying goes. Love the humor, usbcondoms crew! Another one I hope you find a place for in the future: "In the dark, all cats are gray" -- Benjamin Franklin. Yes, really.
fosap 13y ago
Interesting. But I'm looking for the opposite. I often have to access my phone, kindle, whatever data, but do not want to charge it. But I guess the usb controller will not accept a data-only connection.
- cbhl 13y ago
  There are a number of devices (say, USB thumb drives) that run off the power provided by the USB spec, so, no, that wouldn't work for those devices.
- sigstoat 13y ago
  not sure what your other respondent is on about. considering there are usb devices which are self powered, i doubt the host controller would be a problem in this situation. without power on the bus, your phone or kindle might not realize they're connected to something, or wake up and try to communicate with it. you basically just need to cut one wire of the cheapest usb cable you can get your hands on, and then you'll know for sure.
benjamincburns 13y ago
Nifty idea. If you want to make it even better, have it simulate the iPhone/iPad charger ID circuitry so that I can charge my iPad off any old USB charger (provided it's rated high enough). Edit: Actually, scratch that. Leave the data lines connected, but "short" them to the V- line (or shroud, should hopefully be the same thing) with a small capacitor to act as a low-pass filter. I don't have the specs in front of me, but it should be easy enough to filter > 1Mhz down by 3dB and still keep the DC "slew rate" enough to properly ID a charger.
- MertsA 13y ago
  This is how this USB condom should have been made while making sure to use two separate capacitors instead of just shorting the data lines together. The only problem with this approach is that it's physically possible to make a special USB host that pumps enough current down the data lines to fill up that tiny capacitor every cycle. Might want to throw in an inductor for the extra paranoid.
  - benjamincburns 13y ago
    It depends on the size of the capacitor. And even with smaller capacitors, any device which is capable of producing a signal strong enough to overcome even a simple passive 3dB filter well enough to get through the USB handshake, let alone actual device operation, would almost certainly be quite large as compared to a regular charger. Adding an inductor would screw with things, but if we're being really paranoid here, active circuits can measure the resonant frequency of the line and overcome it. Or, even if we're not being paranoid, you've now given someone a nice RCL trampoline to bounce a nice high current into your phone's USB data lines. There are a few ways to protect against all of that if you want to be really paranoid. To start, you could go with a higher order active filter built from a cheap op-amp circuit. More complex varieties could include the use of a tiny 8-bit uC programmed to control a digital pot on the protected side, and an optoisolator somewhere in there just in case there's some weird failure mode which causes a signal path to short from protected to unprotected. The benefit of something like this would be that the controller could also control a light or buzzer to alert the user when a signal is detected on the "unprotected" side. Cheapest and most reliable might be to pump the output of a simple RC high-pass filter into a simple RC low-pass filter (translates to DC bias) then feed that to a comparator which latches the signal lines open (and sounds an alarm) if signal is detected. Or better yet, make it normally open and close only when signal isn't detected.
talles 13y ago
Great idea. Awesome name.
peterwwillis 13y ago
Two things: 1. The data lines can be very important in regulating power output for different devices, and there are different maximums for different versions of USB. Some devices require data communication to charge. Some require proprietary protocols. Implementing Apple product charging is somewhat convoluted, for example, and has changed over time. 2. A friend of mine is a computer engineer, and tells me that correctly implementing USB in hardware is incredibly difficult. It's possible that devices like these might be skimping on parts of the spec to more easily get a working product out the door.
- charliesome 13y ago
  > Implementing Apple product charging is somewhat convoluted, for example, and has changed over time. It is? I've never had any problems with cheap AC to USB power adapters.
  - mbreese 13y ago
    I think they are referring to the higher power ipad charging that pushes more amps down the line than the spec calls for. There is some kind of trigger used to tell the charger to send more juice. This device will probably cause that to not work. So, an ipad on this would only charger at the standard/lower rate.
    - megaframe 13y ago
      The trigger is just grounding the two inner data pins together. This is ok since the data pins are loose pull up so even if the device tries to send data on something with those shorted no damage will occur.
      - mbreese 13y ago
        Right, but my point is that this device won't work with those 'high current' charging devices (at the high current, it will only will only send the standard amps). Unless they included the logic to test this, which, I suppose, is possible.
speedyrev 13y ago
Well to continue the metaphor, I guess I practice abstinence.
- lostlogin 13y ago
  You puritans. Is it still purgatory for me if I try plug USB into the MagSafe?
650REDHAIR 13y ago
Great idea and cute name, but why would you market this on Friday when you won't be taking orders until at least Monday? Seems to me you just lost out on a bunch of sales by showing it off early because it likely won't make the front page again on Monday.
teekert 13y ago
I would like the reverse, block the power lines, so my raspberry pi does not use the backpower of my USB hub through its front USB ports:)
NSAID 13y ago
Oh, this is fantastic. I've been wanting to build something like this into a few cables, but this is even better.
89vision 13y ago
I can't believe nobody has made any "pull-out" quips
deleted 13y ago
[deleted]
Too 13y ago
If you have enough space to lug one of these around you might as well carry with you a complete wall-charger all the time.
bitwize 13y ago
This reminds me of when vendors at tradeshows used to sell "floppy disk condoms" as novelty items. I think there was also at least one transparent keyboard cover billed as a "keyboard condom".
ChuckMcM 13y ago
I heartily approve! The 'juice jacking' discussion (https://news.ycombinator.com/item?id=4951712 https://news.ycombinator.com/item?id=4951712) was calling out for something like this. I hope they sell a zillion of them.
switch72 13y ago
http://www.amazon.com/Retractable-Micro-Charging-Cables-FUNCTION/dp/B004A8OMLQ/ref=sr_1_6?ie=UTF8&qid=1379093288&sr=8-6&keywords=usb+charge+only+cable http://www.amazon.com/Retractable-Micro-Charging-Cables-FUNC...
nicky0 13y ago
This $3 "power only USB charging cable" is another option: http://www.ebay.co.uk/itm/POWER-ONLY-USB-Charging-Cable-Extension-Lead-25cm-/380362788911 http://www.ebay.co.uk/itm/POWER-ONLY-USB-Charging-Cable-Exte...
umsm 13y ago
This doesn't really protect you from a more subtle attack: setting up a femtocell access point for your phone to connect to.
rabble 13y ago
How much do they cost? They're sold out now so they don't list the price. Does anybody know how much they run? Seems like a really good idea to me, there are lots of known USB hacks for phones and somebody smart could probably find away to get the trojan back up on to the person's primary computer.
aglosson 13y ago
I guess I'll just have to wait until they release this in magnum size to accommodate my monster dongle.
deleted 13y ago
[deleted]
deleted 13y ago
[deleted]

376 points by lukashed 13y ago

Even easier, although not as nice-looking: get a common off-the shelf USB Y-cable, plug the power-only male into computer, plug phone into female outlet; done. See e.g. http://easyshop.kiev.ua/images/shnuri/shnuri/Usb-y-power-cable.jpg http://easyshop.kiev.ua/images/shnuri/shnuri/Usb-y-power-cab... for an illustration what the cable looks like. (I have been doing this to charge my phone, as even the USB mount dialog confuses some apps)

aestra 13y ago
Dead link.
- StavrosK 13y ago
  Works for me. It's the cable most portable/USB hard disks come with.
- Piskvorrr 13y ago
  Hmm, weird. Just try searching for "USB Y Cable" images, lots of results like these will pop up: http://www.everythingusb.com/images/list/apricorn-aegis-bio-usb-cable.jpg http://www.everythingusb.com/images/list/apricorn-aegis-bio-... Basically, it's a USB extender cable, with an extra pair of power wires soldered on and terminated in a USB male header - the original use is for power-hungry disks, where you'd plug both the male headers into the computer, increasing the available power (as USB 2.0 can only give 500 mA through a single port, per spec), at the cost of hogging two USB ports. It can be re-used as a USB condom as well.
lnanek2 13y ago
There are actually charging only USB cables out there as well. Heck, I suspect the cable that came with the Chromecast is one, just to save money on data lines that would never be used.
dnautics 13y ago
but why buy another cable, with all the fumbling and whoops I used the wrong cable, when you can buy something that you permanently "by default" keep on the end of the cable that you already have, and take off when you're ready to use the cable for serious.

c-oreills 13y ago

The sales page [1] has a bit more info on what these actually do. [1] http://int3.cc/collections/frontpage/products/usbcondoms http://int3.cc/collections/frontpage/products/usbcondoms

nyrina 13y ago
Is it just me or is this a bit.. Over the top? I've never put my phone into something to charge and thought "Hey, they might steal my data".
- nraynaud 13y ago
  you should
- myhf 13y ago
  Sounds like it would be pretty easy to steal your data.
- nodata 13y ago
  If you are into unprotected charging, then that's up to you.
- dylangs1030 13y ago
  It's actually very serious. Just like ATMs, power stations can look completely harmless while being incredibly dangerous under the surface. Once you connect to a system via USB, it automatically allows data transfer, which makes your smartphone vulnerable to malware and data theft. I can't speak for Android, but iOS 7 now has an automatic warning when you connect to new devices that asks if it should be trusted, presumably to mitigate this risk. However, I doubt anything less than a full hardware solution can actually eliminate the risk entirely. There's a reason why conferences like DefCon warn you explicitly not to use power stations or ATMs nearby - they can be hijacked very easily.
  - Piskvorrr 13y ago
    Well, you should assume that everything out there would be malicious, and work from _that_; if you go to DefCon specifically, this is a reasonable expectation. New-ish Androids pop up a "USB connected, do you want to use this" prompt as well; but many devices (esp. embedded ones) don't.

deleted 13y ago

[deleted]

willvarfar 13y ago

Recently, it comes to light that those handling the Snowden files are using air-gapped computers and passing encrypted data to the outside world via ... USB sticks. Can't USB sticks execute arbitrary code? Couldn't an attacker infiltrate the publically accessible computers that these people use and put a data-stealing trojan onto USB sticks used to bridge the air-gap? Do other media that most computers accept these days e.g. sd cards support arbitrary code execution too? How can you get around this? EDIT: it was DMA attacks that I was thinking off, and USB seems free of them at least. I guess, if you trust the robustness of your USB stack against exploit, that USB is a fairly safe bet. As these very people are reading the NSA secrets, one wonders what'd happen if they discovered some hint that that NSA could do precisely that - exploit via USB plugging in.

kirab 13y ago
It was an old Windows problem that it automatically executed code on mounted media devices. But I hope this was fixed on Windows in the meantime and other OS don’t have this problem.
- guard-of-terra 13y ago
  It's deeper than that. You're plugging a device into your system's bus, the attack surface is huge for that device to steal or modify your data. USB device is a very different beast than CD.
maggit 13y ago
A USB stick could be anything, but if it is simply a proper USB mass storage device, it, by itself, can not execute code on the host machine. To execute code on the host machine, either the host machine has to be stupid (like many Windows versions that try to automatically execute code from plugged-in devices without user interaction) or the device has to be malicious, trying to exploit weaknesses in the host machine. ---- Now, for the files being put on these sticks, there are probably many opportunities to inject a trojan.
nodata 13y ago
Your "usb stick" could be a usb keyboard which changes your password and sets a new one, even sending the data over a 3g connection to an adversary.

nraynaud 13y ago

is it me or this thing is huge ?

StavrosK 13y ago

Can't you achieve the same thing with a cable whose data lines just aren't connected to the jack? Why do you need a whole circuit?

seclorum 13y ago
Because you don't know that you can just cut the data wires in a cheap USB cable, and want to be 'protected' by a cool hipster toy that'll sit in your laptop/phone baggie until you're at some party and can shout in triump when someone plugs in their phone 'just to charge': "NO, USE MY USB CONDOM!!" EDIT: if this thing actually had some diagnostic LED's that would show you that the 'power port' was trying to do something nefarious on the data lines, it'd be a lot more useful than an ultra-cheap snipped cable imho ..
morsch 13y ago
Sure. The advantage of this is you don't have to cut open one of your cables, you can easily (and visibly) decide whether you want the data pins connected or not and this works for any USB device, ie. USB micro as well as Apple and other proprietary connectors.
- icebraining 13y ago
  you can easily (and visibly) decide whether you want the data pins connected or not You could just get two cables, and only patch one. this works for any USB device So would the cable option if you used a male / female cable instead of a male / male one.
- bho 13y ago
  actually I think you can just stick some electrical tape over the data pins in a standard USB cable. not sure how this device does anything different.
delgaudm 13y ago
There is a ready made charge only cable from Mediabridge. Amazon: "Mediabridge USB Charging Cable - (6 Feet) - USB-A Male to Micro-B Charging Cable"

Egregore 13y ago

There are external batteries for phones, when you charge through them I think no data will be lost.

rbanffy 13y ago
As long as you trust your external battery

jablan 13y ago

At first I thought it was a device which would prevent an infected computer from writing malware to the inserted flash drive, as a hardware antivirus.

deleted 13y ago
[deleted]

smoyer 13y ago

It might be a bit smaller, but the concept has been around a long time (I use my external hard-drive's cable): http://www.amazon.com/s?ie=UTF8&page=1&rh=i%3Aaps%2Ck%3Acharge%20only%20usb%20cable http://www.amazon.com/s?ie=UTF8&page=1&rh=i%3Aaps%2Ck%3Achar...

hwh 13y ago

For those who didn't click through everything: This devices is an adapter that cuts the data lines for a USB connection. Such a device will most probably restrict the device (if it properly implements charging) to a maximum charging current of 100mA. The data lines are used for identifying the maximum current allowed.

Kliment 13y ago
You can stick a resistor on the data lines to pretend to be a high-power charger.
- hwh 13y ago
  Or implement other identification mechanisms that exist or might evolve. Yes. But in the same run, that might take too much from the port you plug it in mistakingly. If you don't trust the port, you will often not even know what it is. It's probably safe to assume it will indeed give you 500mA (when it's in the device or a powered hub). What about the 1500mA ones? That said, if one desperately needs to charge a battery, one is likely to take even 100mA. Cutting two lines of a cable doesn't seem that hard and ugly compared to a un-encased PCB, though.
  - Kliment 13y ago
    What? A patched-together table is much uglier than a bare PCB, particularly with nice layout.
    - michaelt 13y ago
      Depends if your use case involves coming into contact with anything conductive.
  - deleted 13y ago
    [deleted]
yungchin 13y ago
According to these guys, if the data lines are shorted according to the "dumb usb" spec, you should be able to draw whatever the port can provide: http://www.portablepowersupplies.co.uk/portapow-fast-charge-micro-usb-cable/ http://www.portablepowersupplies.co.uk/portapow-fast-charge-...

Jugurtha 13y ago

Well, like everything else .. Marketers are betting on the laziness of people. Why tell someone he can lose weight by working out and eating less, when you can sell them a pill that makes them lose weight while they sleep and get abs in 7 minutes? Why learn programming in several years, when you can "learn programming in three days". Why tell people to be cautious with their data, not to click on everything, when you can sell them a "condom" that enables them to remain reckless and careless and lazy ?

rbanffy 13y ago
You can also just cut wires 2 and 3 of your cable.
Piskvorrr 13y ago
Some attacks do not depend on user interaction ("clicking"); plugging the device in might be sufficient. Thus, hardware air-gap becomes necessary. (of course, this just shifts the problem around: now you need to trust the "usb condom"; but given its simplicity, it should be much harder to put anything nefarious there)
- Jugurtha 13y ago
  Yeah. I looked at it from a "consumer education" perspective, but it is unrealistic to ask for that. Not everyone is interested in those things. However, what does that thing actually do ? How does it work? Signatures ? Block "autorun" or something ? I didn't see any details.
  - Piskvorrr 13y ago
    The USB condom? Much lower-level than that: no data pins, only power.

the_mitsuhiko 13y ago

Does anyone know how the voltage negotiation works for those?

Piskvorrr 13y ago
It doesn't - therefore, a to-spec USB2.0 host should not give more than 100mA over the condom, but good luck finding such a beast (most hosts will happily serve 500 mA w/o negotiation).
- hwh 13y ago
  Nitpick: It's current negotiation, not voltage negotiation. As for voltage - 5V is universal with USB. And as for current - I wrote about the matter in another reply to the OP: The problem will be a well-behaved USB device simply won't take more than 100mA. I.e. it will use the "flat" charging curve, even if the host could deliver more.
  - SEMW 13y ago
    > As for voltage - 5V is universal with USB Nitpick for interest's sake: apparently there's a new (2012) 'USB Power Delivery' spec[1] which specifies two new voltage levels (12V & 20V) in addition to 5V, with higher current limits (2A at 5V, 3A at 12V or 20V for microUSB connectors). Obviously both ends (and the cable) have to support it; I don't know if anything actually does yet. [1] http://www.usb.org/developers/powerdelivery/ http://www.usb.org/developers/powerdelivery/
  - Piskvorrr 13y ago
    Pedantry: That should be obvious from the units, wouldn't it? (Volts for voltage, amperes for current, ohms for resistance) I do agree that the general public uses these interchangeably, bringing confusion :) As for a well-behaved device - there aren't very many of those, either. Fortunately, this is less of a problem with USB3 - more devices follow the spec closely.

oemera 13y ago

It could be way more popular if these wouldn't be called 'condoms'. Some people can get offended and wont buy it even if it would be useful. Just my 2 cents.

kawsper 13y ago
Why would someone be offended by the word "condom" ?
sdfjkl 13y ago
USB prophylactics?
- joezydeco 13y ago
  USB Data Isolator.
mbarrett 13y ago
the USB Condoms nomenclature is likely the reason it is getting exposure. For a first run, I'd say it was definitely successful considering its sold out. But you're right, retail would probably suggest a name change.

auggierose 13y ago

"If you're going to run around plugging your phone into strange USB ports, at least be safe about it. ;-)" Exactly. Better safe than sorry.

lechevalierd3on 13y ago

The all NSA scandal is a quite sad revelation, but there a re so many business idea to built off it.

contingencies 13y ago

When I feel my batteries are low, I like to get my juice flowing by plugging in to the nearest socket available. Sometimes, I even get a surface to sleep on, and when that happens, often I get to load up on media. Sometimes when the media's done there's some funny business. Occasionally, I even get a special powerup for breakfast. There's nothing like waking up in the morning after a new encounter, wealthier for the memories, fully charged and ready to go. - Anonymous mobile device, 50 Bistreams of "Hey!"

Fuxy 13y ago

Yay! I don't have to build this anymore.

gametheoretic 13y ago

>"Any port in a storm." as the saying goes. Love the humor, usbcondoms crew! Another one I hope you find a place for in the future: "In the dark, all cats are gray" -- Benjamin Franklin. Yes, really.

fosap 13y ago

Interesting. But I'm looking for the opposite. I often have to access my phone, kindle, whatever data, but do not want to charge it. But I guess the usb controller will not accept a data-only connection.

cbhl 13y ago
There are a number of devices (say, USB thumb drives) that run off the power provided by the USB spec, so, no, that wouldn't work for those devices.
sigstoat 13y ago
not sure what your other respondent is on about. considering there are usb devices which are self powered, i doubt the host controller would be a problem in this situation. without power on the bus, your phone or kindle might not realize they're connected to something, or wake up and try to communicate with it. you basically just need to cut one wire of the cheapest usb cable you can get your hands on, and then you'll know for sure.

benjamincburns 13y ago

Nifty idea. If you want to make it even better, have it simulate the iPhone/iPad charger ID circuitry so that I can charge my iPad off any old USB charger (provided it's rated high enough). Edit: Actually, scratch that. Leave the data lines connected, but "short" them to the V- line (or shroud, should hopefully be the same thing) with a small capacitor to act as a low-pass filter. I don't have the specs in front of me, but it should be easy enough to filter > 1Mhz down by 3dB and still keep the DC "slew rate" enough to properly ID a charger.

MertsA 13y ago
This is how this USB condom should have been made while making sure to use two separate capacitors instead of just shorting the data lines together. The only problem with this approach is that it's physically possible to make a special USB host that pumps enough current down the data lines to fill up that tiny capacitor every cycle. Might want to throw in an inductor for the extra paranoid.
- benjamincburns 13y ago
  It depends on the size of the capacitor. And even with smaller capacitors, any device which is capable of producing a signal strong enough to overcome even a simple passive 3dB filter well enough to get through the USB handshake, let alone actual device operation, would almost certainly be quite large as compared to a regular charger. Adding an inductor would screw with things, but if we're being really paranoid here, active circuits can measure the resonant frequency of the line and overcome it. Or, even if we're not being paranoid, you've now given someone a nice RCL trampoline to bounce a nice high current into your phone's USB data lines. There are a few ways to protect against all of that if you want to be really paranoid. To start, you could go with a higher order active filter built from a cheap op-amp circuit. More complex varieties could include the use of a tiny 8-bit uC programmed to control a digital pot on the protected side, and an optoisolator somewhere in there just in case there's some weird failure mode which causes a signal path to short from protected to unprotected. The benefit of something like this would be that the controller could also control a light or buzzer to alert the user when a signal is detected on the "unprotected" side. Cheapest and most reliable might be to pump the output of a simple RC high-pass filter into a simple RC low-pass filter (translates to DC bias) then feed that to a comparator which latches the signal lines open (and sounds an alarm) if signal is detected. Or better yet, make it normally open and close only when signal isn't detected.

talles 13y ago

Great idea. Awesome name.

peterwwillis 13y ago

Two things: 1. The data lines can be very important in regulating power output for different devices, and there are different maximums for different versions of USB. Some devices require data communication to charge. Some require proprietary protocols. Implementing Apple product charging is somewhat convoluted, for example, and has changed over time. 2. A friend of mine is a computer engineer, and tells me that correctly implementing USB in hardware is incredibly difficult. It's possible that devices like these might be skimping on parts of the spec to more easily get a working product out the door.

charliesome 13y ago
> Implementing Apple product charging is somewhat convoluted, for example, and has changed over time. It is? I've never had any problems with cheap AC to USB power adapters.
- mbreese 13y ago
  I think they are referring to the higher power ipad charging that pushes more amps down the line than the spec calls for. There is some kind of trigger used to tell the charger to send more juice. This device will probably cause that to not work. So, an ipad on this would only charger at the standard/lower rate.
  - megaframe 13y ago
    The trigger is just grounding the two inner data pins together. This is ok since the data pins are loose pull up so even if the device tries to send data on something with those shorted no damage will occur.
    - mbreese 13y ago
      Right, but my point is that this device won't work with those 'high current' charging devices (at the high current, it will only will only send the standard amps). Unless they included the logic to test this, which, I suppose, is possible.

speedyrev 13y ago

Well to continue the metaphor, I guess I practice abstinence.

lostlogin 13y ago
You puritans. Is it still purgatory for me if I try plug USB into the MagSafe?

650REDHAIR 13y ago

Great idea and cute name, but why would you market this on Friday when you won't be taking orders until at least Monday? Seems to me you just lost out on a bunch of sales by showing it off early because it likely won't make the front page again on Monday.

teekert 13y ago

I would like the reverse, block the power lines, so my raspberry pi does not use the backpower of my USB hub through its front USB ports:)

NSAID 13y ago

Oh, this is fantastic. I've been wanting to build something like this into a few cables, but this is even better.

89vision 13y ago

I can't believe nobody has made any "pull-out" quips

deleted 13y ago

[deleted]

Too 13y ago

If you have enough space to lug one of these around you might as well carry with you a complete wall-charger all the time.

bitwize 13y ago

This reminds me of when vendors at tradeshows used to sell "floppy disk condoms" as novelty items. I think there was also at least one transparent keyboard cover billed as a "keyboard condom".

ChuckMcM 13y ago

I heartily approve! The 'juice jacking' discussion (https://news.ycombinator.com/item?id=4951712 https://news.ycombinator.com/item?id=4951712) was calling out for something like this. I hope they sell a zillion of them.

switch72 13y ago

http://www.amazon.com/Retractable-Micro-Charging-Cables-FUNCTION/dp/B004A8OMLQ/ref=sr_1_6?ie=UTF8&qid=1379093288&sr=8-6&keywords=usb+charge+only+cable http://www.amazon.com/Retractable-Micro-Charging-Cables-FUNC...

nicky0 13y ago

This $3 "power only USB charging cable" is another option: http://www.ebay.co.uk/itm/POWER-ONLY-USB-Charging-Cable-Extension-Lead-25cm-/380362788911 http://www.ebay.co.uk/itm/POWER-ONLY-USB-Charging-Cable-Exte...

umsm 13y ago

This doesn't really protect you from a more subtle attack: setting up a femtocell access point for your phone to connect to.

rabble 13y ago

How much do they cost? They're sold out now so they don't list the price. Does anybody know how much they run? Seems like a really good idea to me, there are lots of known USB hacks for phones and somebody smart could probably find away to get the trojan back up on to the person's primary computer.

aglosson 13y ago

I guess I'll just have to wait until they release this in magnum size to accommodate my monster dongle.

deleted 13y ago

[deleted]

deleted 13y ago

[deleted]