Proxmark3, Implants and bluetooth

I think support was the best for for this. Although this is just an observation. I have a proxmark rdv4 (That I love by the way) I recently got the blue shark module for it. One thing I have noticed with my low frequency tags is even with the implant antenna, when using Bluetooth it is almost impossible to get a read on my xEM implant or my Next. 13.56 I have no problems. 125 cant read a thing if Bluetooth is on . I can write to them no prob but not read if Bluetooth is on.

Now if I am plugged into the Proxmark I read just fine even with the stock antennas as long as Bluetooth is off on the module. So just a heads up if you are having troubles reading this may be the problem for you as well.

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No difference in read performances for me. But it’s much slower with the Blueshark in LF.

The reason for this is, all HF operations are handled by the PM3 itself, whereas LF operations are handled by the client. That means what goes across the BT serial connection with HF is just the result of the operations, but with LF, the entire samples buffer is sent across for analysis by the client’s software. Since the BT connection is much slower than a direct USB connection, the performances aren’t terribly impressive, but it works.

However, I have a feeling I might know a possible cause for your problem: are you on Linux? If you are, can you check that ModemManager is running when BT is on and paired (even if you’re connected to USB)? If it is, disable or uninstall it and try again.

So how does LF standalone mode work? I compiled with LF_ICEHID, and my proxmark will capture and record all Prox/AWID cards and save them to internal memory without any use of the client software.

Standalone modes are different. They only do one thing. But the general, “computer connected” mode of operation for LF is to ship off the samples to the client for decoding. I think it’s legacy code that could (should?) probably be handled by the PM3 now, but has been kept around because, well, it works…

Also, unlike LF, HF involves a two-way communication with the transponder, with often tight delays. That’s probably why it’s handled by the PM3, so it answers in time.

My lf standalone works great. keep in mind this only effects my lf implants I have no problem reading cards over Bluetooth

Okay, then your Blueshark is putting out interferences somehow.

The thing is, with full-size cards, the voltage swing at the antenna can easily reach 10V. Very easy to detect. But with implants, they barely reach 1V at the best of times. Even with the ProxLF, it’s not terribly impressive. If your Blueshark is putting out noise, it’s probably drowning out the signal from the chip.

I’d suggest you reseat the white ribbon cable, see if it improves things. If it doesn’t, you might want to consider returning it - or hitting the Proxmark forum to ask for advice.

Ya I should put a post up Iceman is pretty quick to comment. I will try re seating the ribbon cable. Its not a huge issue for me as it works for everything I need and I can just cable to my phone when reading implants.

I am not on linux this is with my android phone. You do bring up and interesting point though. I have yet to try and see if I get the same results when using Bluetooth with my win10 machine. I have modem manager uninstalled on my centos box but rarely use the proxmark on that one.

Well, from what you describe, that wouldn’t be your problem. ModemManager typically will intersperse AT commands in the communication between the PM3 and the client, messing everything up. Typically you get error messages about malformed frames in the client.

But you say your PM3 works with full size cards, but not with implants, when it’s connected to USB and the BT module is on. That’s a totally different symptom, one that screams “interference noise” to me.

So trying it out on my pc I had no problems whats so ever. Bluetooth on plugged in, not plugged in, stock antenna, and lf antenna, read every time. The problem seems to be on the phone only. Im leaning towards interference as well. The Bluetooth on my computer has a ridiculous external antenna on it vs my phone with its poor thought out BT antenna. Thanks Samsung.

That’s the exact error it looks like it is reading it but not getting all of it

Hmm, actually that looks exactly like the issue I had with ModemManager.

Check out the thread I had opened on the Proxmark forum about it. It looks eerily similar to your problem: http://www.proxmark.org/forum/viewtopic.php?id=7958

Also, you do know you need a special firmware to use with Android, right?
http://www.proxmark.org/forum/viewtopic.php?id=6804

According to the latest release of the blue shark manual they are using the normal iceman github source the only difference is in the makefile.platform where you have to un-comment the Bluetooth add on.

I will build and test the other firmware though and see if it clears up the issue.

And yes this looks like the same issue you where having.