Setting USB-C port as power only

This is going to sound a bit paranoid – but …

I was given a gift of a high-capacity laptop charging battery. It is a fairly hefty device with several MAC related cables (mag safe and USB-C). My wife’s laptop is a bit older than mine and she still has a magsafe connector but I have a 2016 touch bar MAC with 4 USB-C ports. Given that this device is made in China by a company that I have no familiarity with (Maxoak) I am a little nervous about connecting it to a port that can transfer data (in either direction). Obviously my wife can use it with no qualms, but I am holding back right now.

So… question… is there any way (e.g. CLI command) by which I can specify that USB-C port (or maybe a pair since I think they are paired on the chip) can be set to ONLY take power and not do any USB or Thunderbolt transfers?

Why use a device (free or not) that you have reason not to trust?

I am not right now. That was the point of my post. But if I could, out would be useful. This is one of the downsides of combining data and power on the same port. I frequently have the same paranoia with USB power ports for phones like in airports etc. I usually opt to pull out my power brick and just plug into an AC receptacle.

Just to understand your thoughts:

you are concerned because the producers is a Chinese company and you see it in the range of possibilities, that they are transferring all data of all their customers back to their data center? Or do you see that device having a kind of function to turn the data transfer on and off based upon somebody’s interest in China?
How would they know, whom they are selling it to and if they are interested in that data?

Three suggestions:

  1. Give the charger to a charity
  2. Give the charger to your wife
  3. Shut the laptop down, charge, remove charger, power up laptop

The easy way of doing this is via the terminal by running

sudo kextunload /System/Library/Extensions/IOUSBMassStorageClass.kext

What that will do is unload the USB storage driver until you next reboot, or you could use management profiles to disable the ports.

I would echo what the others have said and if you don’t trust the device don’t use it, I would be inclined to bin it or shelf it though rather then giving it to your wife or charity.

If you do want to use it though see check online to see if anyone has taken one apart it should be pretty obvious to tell if it had the ability to phone home.

Lastly most likely it’s fine, it’s kinda not in these manufacturers best interests to be intentional stealing data, since it’s a margins business and risking losing the EU and US markets over spyware is a risk many wont make, it’s not to say that they won’t try to collect some data like the computer model and leave a security hole wide open.

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Thanks @Ben_Lincoln that’s the type of response I was looking for … but it is a sledgehammer and i was looking for a tack hammer. It seems to me that being able to dynamically enable and disable data transfer on a port is likely within the capabilities of the device.

Obviously the odds of this device being a problem are a million to one (likely much less than that) but like I said above putting data and power on the same connector does raise some issues.

(And I would probably be more concerned about them putting software on my system than taking it off).