Questions about USB functionality

Dalen_P

Beta member
Messages
5
Location
U.S.A
I was just wondering if it was possible to design a system that would allow temporary full communication between a computer and a USB peripheral (mainly for the purpose of installing drivers and such) and then disabling all traffic to the peripheral while still allowing traffic to the computer. I was thinking this was not possible due to the protocols that USB uses, but I've been wrong before. Similar to a Kanguru flash drive, but as a separate device.
 
Last edited:
temporary full communication between a computer and a USB peripheral (mainly for the purpose of installing drivers and such) and then disabling all traffic to the peripheral while still allowing traffic to the computer.

Just curious but what type of peripheral would you be using with your idea ?
I'm not gonna lie here, but it "might" not be possible to do what your thinking.
Maybe through a r45 ethernet cord if you planned on doing it wired or wireless with a server/router.

Read this here if you haven't and tell me if this is something your aiming for:
One thing I do know you would have to program the device to get your idea going.
USB - Wikipedia, the free encyclopedia
 
I wanted to do this with a flash drive, so I essentially could make a flash drive with a switch to make it read only. (Similar to how floppy drives worked) Kanguru actually already made a flash drive that does this, but I wanted to know if you could design a device that sat in between the drive and the computer, essentially turning any drive into a read only drive. My only concern was that it seems the computer often asks for information from the drive, which if incoming signals to the drive are blocked completely, it wouldn't receive.
And yeah, I already read everything I could find on how USB works, but thanks.
 
My only concern was that it seems the computer often asks for information from the drive, which if incoming signals to the drive are blocked completely, it wouldn't receive.

Here's your main issue, if the cpu of a computer gives out instructions and tells other hardware or devices attached what to do.
How is the device able to tell the cpu what it needs to do and vice versa without a direct conflict ?
I'll contact a good friend of mine and see what he thinks.
 
IMO, talk to an electrical engineer that's familiar with USB / data transfer. I would imagine you would have to have a switching diode or something, that would block signal going into the USB drive on the 2 data pins. The diode would only allow 1 directional flow - and when switched off would allow 2 way flow.

Now, honestly, I have no idea if this would work because my background in electrical engineering is jack squat - but my basic knowledge of electronics would suggest something along those lines. I'm sure there are risks in the above mentioned example; hell, not sure if it would even work that way using a diode lol. Like I said - talk to an electrical engineer who would have the proper background knowledge.

Here's your main issue, if the cpu of a computer gives out instructions and tells other hardware or devices attached what to do.
How is the device able to tell the cpu what it needs to do and vice versa without a direct conflict ?
I'll contact a good friend of mine and see what he thinks.

From what I remember from my computer architecture class and Operating Systems class, usually it's the OS that tells the CPU what to do and handles all the requests. The CPU is just a powerful calculator essentially, which handles the operations sent to it through device controllers, OS, motherboard controllers, etc., and redirects flow/instructions through the BUS to their proper destination. As well as keeping track of program counters/indexes, and performing other calculations. Just an FYI, is all.
 
Last edited:
IMO, talk to an electrical engineer that's familiar with USB / data transfer. I would imagine you would have to have a switching diode or something, that would block signal going into the USB drive on the 2 data pins. The diode would only allow 1 directional flow - and when switched off would allow 2 way flow.

Now, honestly, I have no idea if this would work because my background in electrical engineering is jack squat - but my basic knowledge of electronics would suggest something along those lines. I'm sure there are risks in the above mentioned example; hell, not sure if it would even work that way using a diode lol. Like I said - talk to an electrical engineer who would have the proper background knowledge.

I spoke with my comrad about this:
[geekboy]
As far as I know it's doable with a device that intercepts the usb packets and forwards only valid packets. This is essentially a usb sniffer and is honestly more work then it's worth. It's simpler to design a flash drive with a microcontroller in it that just pulls the write enable on the flash chip once it's deemed to enter readonly mode based on what ever factors you wanted.

He says it maybe possible to do, if thats the case, seek out a electrical engineer for this.
 
Thanks for the suggestions, I was worried that I would have to do something like that. Oh well, I suppose that I won't be able to do it for now. It's actually kind of sad, because I would have used it to prevent viruses from spreading onto flash drives. At our school, our IT department is incompetent and our systems are outdated and underfunded. It's very common to get viruses that spread on flash drives.
 
Last edited:
Thanks for the suggestions, I was worried that I would have to do something like that. Oh well, I suppose that I won't be able to do it for now. It's actually kind of sad, because I would have used it to prevent viruses from spreading onto flash drives. At our school, our IT department is incompetent and our systems are outdated and underfunded. It's very common to get viruses that spread on flash drives.

Hmm if you don't mind me asking what kind of systems do you run by chance ?
Also what type of antivirus and security suite do you use on the school computers ?
Funded or no funded, there are some legitimate free antivirus sofware you can use.
 
All of our computers run windows XP with Novell login systems and no real network security as far as I can tell (looking through the unprotected server files once, we found the logins for every account, including the admin ones). As for antivirus, as far as I know, absolutely none. After the viruses started to become an issue they tried using Panda USB Vaccine, but it didn't seem to help. I think the best bet is to install Malwarebytes (as I know for a fact it can recognize this particular virus), but the multi-computer licences are ridiculously expensive, so they would have to install it on each computer one by one. Not to mention, being a student at this school, it's automatically assumed that I don't know enough about computers to be of any use. So, I was looking for alternative options, such as a read only flash drive.
 
Last edited:
All of our computers run windows XP with Novell login systems and no real network security as far as I can tell (looking through the unprotected server files once, we found the logins for every account, including the admin ones). As for antivirus, as far as I know, absolutely none. After the viruses started to become an issue they tried using Panda USB Vaccine, but it didn't seem to help. I think the best bet is to install Malwarebytes (as I know for a fact it can recognize this particular virus), but the multi-computer licences are ridiculously expensive, so they would have to install it on each computer one by one. Not to mention, being a student at this school, it's automatically assumed that I don't know enough about computers to be of any use. So, I was looking for alternative options, such as a read only flash drive.

Heh I can see why you came down here then.
Also about the schools security, my mothers school system runs something similiar to what you have.

Download Microsoft Security Essentials from Official Microsoft Download Center

auto scan of usb drive with MSE - Microsoft Community

https://www.piriform.com/defraggler
Here you go that would be a great way to start it out.
If needed have one of the IT admins at the school look at this thread.
If they agree with my post, have them run it on each system.
Scan each computer for infections over night and have it defrag.

If they still blow you off after all of that, all you can do is walk away and use your own machine.
Pray hope they don't infect everything in the school leading the government to crack down on them.
 
Back
Top Bottom