nrF52840 is not decrypting packets when using LE secure connections with passkey entry and debug keys

[Eric Larson]

I followed all the steps that are documented. Below is a screen capture of WireShark. 

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One device is the Central which generates a passkey that's scrolled across its screen. The other device is a peripheral that's linked by a iOS device to transfer the key. The setup has been tested and works on a Ellisys analyzer. So what am I missing? thanks.

notDecrypting.pcapng

[Kenneth]

I will pass you sniffer logs to the team to get their feedback. 

Kenneth

[Kenneth]

From the logs the ellisys capture has the peripheral using the Debug keys.

In notDecrypting_3.pcapng none of the devices are using the debug key. The data of the L2CAP fragment start should look like: 41 00 06 00 0c e6 9d 35 .....

You should do the ellisys and nrf sniffer in parallell, to ensure that you are comparing apples and apples.

Best regards,
Kenneth

[Eric Larson]

Now it's working. When you pointed out that the notDecrypting_3.pcapng wasn't using the debug keys I went back to the TI stack and checked were the keys are enabled. The default setting for the triggering the key use needs to be set to TRUE when in SC_HOST_DEBUG mode. I've documented for anyone who may have similar problem.

Thanks for your patience with me in helping me solve this problem.