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Comment by stevehawk | Hacker News Reader

I guess I'm an old fogey now (35) but I don't want a USB C charger. I want a non data transferring power plug that can't be used to compromise my machine should a manufacturer opt to do that. I also only use power bricks to charge my phones/tablets at public charging places instead of the supplied USB cables.

Are there power only Type C cables for charging? Is there some pressing need to reduce the ports on the side of a laptop? I didn't buy the thing to be stylish and impress women, I bought it to get shit done.

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> I want a non data transferring power plug that can't be used to compromise my machine should a manufacturer opt to do that.

At least in Linux you can disable automatic binding of kernel drivers to devices like so:

    echo 0 >/sys/bus/usb/drivers_autoprobe

You can plug in a keyboard and even though the device is recognized and listed in "lsusb", it's not used as a keyboard (or network device, soundcard, scanner, ...)

    # dmesg
    [ 1017.031703] usb 1-10.4: new low-speed USB device number 8 using xhci_hcd
    # lsusb -s 1:8
    Bus 001 Device 008: ID 046d:c30e Logitech, Inc. UltraX Keyboard (Y-BL49)

I can type on this newly connected keyboard, but no key presses are recorded on the console or on X-windows. My other (also USB) keyboard that had been connected before is still working fine, though.

This can even be done with a different mechanism on a per-bus basis as described in https://www.kernel.org/doc/Documentation/usb/authorization.t...

If I decide to use the 2nd keyboard, I'll manually bind this device to the usb hid driver like so:

    # echo 1-10.4:1.0 > /sys/bus/usb/drivers/usbhid/bind

(the :1.0 comes from the different functions one single USB device may offer) And from this point on the keyboard works normally.

I have no idea why no one bothered to make a nice gui for this feature (which also works on other busses), or why it's not standard to popup some message-box on other OSs (e.g. Windows) whenever something is plugged in a port, before even trying to load any drivers.

(edit: added 2nd part where I manually bind)

>I have no idea why no one bothered to make a nice gui for this feature

Getting off-topic, but this remark can be applied to most aspects of Linux OS's tbh. We developers are too comfortable with the shell on Linux, whereas with it being such a pain on Windows, the devs themselves are more inclined to write small GUIs left and write to solve their problems.

Yes, I know. And it's sad. I'm also not a "gui" person, and couldn't make a useful graphical interface if my life depended on this.

But I'm especially confused as why this hasn't been built into Windows for years, especially considering how many people were e.g. hurt by "Autoplay" in the old days:

    You've plugged in a device that claims to be...
        [ ] a mouse (driver available)
        [ ] a storage device (driver available)
        [X] a soundcard (driver will be downloaded and installed)
    Tick any of the functions you want to activate, or press CANCEL
    if you don't want to activate any functions of this device, e.g.
    because it's a phone you just want to charge from your laptop.

(of course the wording is utter crap, but you might get the idea...)

That's pretty neat. To make it user friendly I guess you'd have to whitelist attached devices during OS install/setup then prompt for others moving forward. Or whitelist keyboards/mice in general but not other devices.

That's a reasonable concern - there are USB 'condoms' that ensure the connection is for charging only. http://syncstop.com/

I am a bit older than you (36) and I think USB C charging is a great idea. I just bought a Nintendo Switch, and it is has USB C charger. It would be great if all my other devices could use the same type of charger so I don't have to carry multiple cables/charging bricks with me.

I'm even older (41) and it has nothing to do with this discussion at all :-p

For the record, the sooner everything is USB C the better. Someone can make data-blocking charge-only cables.

> Someone can make data-blocking charge-only cables.

I thought the one Apple ships with the MacBook is a charge-only cable.

[edit]I'm 46 - I would hate to break a thread[/edit]

The USB-C cable that comes with a MacBook's power adapter is not charge-only but only supports USB 2.0 throughput for data [0]. I think that means it also can't be used for things like DisplayPort Alternate Mode.

BTW, if you order an extra USB-C power adapter from Apple [1], it does not come with any cables, not USB-C, not AC for use between the brick and the wall. It only comes with the fold-out prongs (I don't know what non U.S. models are like) but thankfully they didn't change that connector type so if you have an AC cable from a MagSafe adapter, you can use it.

[0] https://www.apple.com/shop/product/MLL82AM/A/usb-c-charge-ca...

[1] https://www.apple.com/shop/product/MNF72LL/A/61w-usb-c-power...

> I guess I'm an old fogey now (35) but I don't want a USB C charger.

Surface and Macbook's aren't targeted at your user profile unfortunately. There are countless other laptops that fit your usecase?

These high-end flashy laptops are always going to be doing stuff like pushing for immature tech. But if you're the type of person who uses this stuff then you likely have a phone that also uses USB-C.

I bought a Nexus 6P and I love the power/speed of USB-C. On a number of incidences it's made my life easier, sometimes transferring data, mostly the speed of charging, but also I find the build quality to be top notch. USB-C seems to just be a better design than micro-USB.

I had lots of trouble with USB cords being twisted and being broken but after a year I have yet to have this problem with the various USB-C cords I use.

Remember cell phones before Mini USB took over/was mandated by the EU? At many events there used to be booths that would make money by having every charger cable available to charge your phone.

It's great to have a unified connector for everything. My USB-C NexusX cable can charge my friends Macbook.

And eventually, hopefully, in a few years time, it will also mean that wherever you go for a presentation, a USB-C option will be available. There is a really good chance that this will eliminate a lot of duplicate cables and dongles.

For USB-C phones only, not laptops: http://www.portablepowersupplies.co.uk/portapow-data-block-c...

What's really needed is both a magsafe-style port as well as a USB-C port capable of charging. Use the magsafe charger when you've got it around, and retain the flexibility to charge through USB-C when that's what's available.

In that case, maybe you do want the $40 magnetic cable[1] someone else mentioned in this thread.

[1] https://griffintechnology.com/us/breaksafe-magnetic-usb-c-po...

Laptop chargers are not as mobile chargers; when you connect a USB, the USB cannot just read the computer's data. It also cannot execute a program. This all comes from USB sticks that got so infected. 0-days aside of course.

Sure it can. All it needs to do that is to emulate a HID device and act as an keyboard or mouse. You might notice when it starts opening cmd/shell and typing commands, or not, or at least not fast enough. Or you may not understand what's happening and ignore the black box that popped up for a while on your desktop.

While valid, that is a totally different scenario from what the OP wants to protect from. I am just pointing out that when connecting a phone and a laptop to an USB the default is that phones are unsecure and laptops are secure-ish. 0days, badUSB and all applies of course.

My phone prompts me for access before it trusts a USB device, my computer loads drivers for it, sometimes without prompting. This seems like the opposite of the situation you describe.

Actually that's exactly the scenario. I could make a USB C charger that is also a memory device with an autorun zero day and while charging your laptop I'm compromising it as well.

Be it portable, individual adapters or public access ones in airports.

But that MagSafe or any other power only adapter? It's not compromising anything

USB-C chargers can of course pretend to be whatever they want, including an infected USB stick.

Sure -- but it wouldn't be out of the realm of possibility to quickly swap someones cable with a look-alike that could. I'd think that'd be more likely than the original hardware manufacturer implementing phone home or something.

Your charger may not be harmful but that doesn't mean all chargers won't be or that all USB ports are safe.

Imagine if everyone used USB-C then we'd get to the point where no one would carry their charger with them because they could just borrow a charger or plug their computer into a random USB charge port at the Airport or Hotel.

At that point anyone could just setup a free "charge station" that would attempt to execute any number of nefarious exploits against anything plugged into them.

Yes. There are power only USB-C cables. In fact, the one that comes with the new MacBook Pro is power only.

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