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The humble USB cable is part of an electrical revolution

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Re: The humble USB cable is part of an electrical revolution

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post #21
post #3

It's going to be interesting, from a security standpoint. One of the original cracks on the PS3 was via the USB stack. I'd not go plugging my computers or phones into jacks that I don't necessarily control. I can see a market for buffering devices that allow power through, and perhaps do power negotiation for you, but that do not allow data traffic. I believe these devices already exist. though I don't know how sophi…

Even worse than USB is Firewire, which, if I am not mistaken, gives direct memory access to whatever device is connected. However, manufacturers are already realising that blindly trusting every USB host is a bad idea. For example, iPhones now ask if you want to trust if you connect to a previously unknown computer via USB. If you chose not to, your iPhone will take power, but won't allow data access. Therefore it's…

Yes, FireWire is bad in this regard, because it normally allows devices direct DMA to other devices memory space. This is also what makes/made it so popular for high-bandwidth/low-latency applications.

But keep in mind that this is something that a host actually has to turn on for every single device on the bus[1], but probably most drivers are lazy and just unconditionally enable this globally.

[1] See PhysicalRequestFilter in the OHCI specs http://download.microsoft.com/download/1/6/1/161ba512-40e2-4...

Re: The humble USB cable is part of an electrical revolution

#62
post #5

Earlier quoted context omitted.

(I'm not an engineer). I a similar article; iirc android phones could be owned by plugging them into a hostile usb connection. I wonder, though, if you couldn't produce a simple adapter that just drops some of the pins? Maybe I don't know enough about usb.

You can buy just such an adapter from the link below; Version 2 is in the works, which will include a microprocessor to allow for full-power charging. http://int3.cc/products/usbcondoms

thank you jdietrich

Re: The humble USB cable is part of an electrical revolution

#63
post #23

Earlier quoted context omitted.

or you can just cut the two data cables or put a piece of tape on the two data connectors on a usb2 cable.... pleaaaase and it's almost free...

Doesn't solve the low/high power signal for rapid charging.

indeed, will probably fallback to either one of those depending upon device parameters, a small price to pay for those not willing to risk
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