RE: Unable to sniff LE Secure Connections in debug mode using nRF52840 Dongle

Einar Thorsrud — Mon, 08 May 2023 12:37:11 GMT

Hi,

The nRF sniffer will automatically be able to decrypt packets after listening on on a LESC pairing procedure if one or both of the peers use the debug key and the sniffer was able to sniff all the relevant packets during the pairing procedure (see Sniffing the pairing procedure of a connection).

I see from the sniffer trace that the debug key is not used in #3735 (as this is not the debug public key you can see in your snippet from the spec or as debug_public_key in ecc.c), but the commands you show seems to indicate that it should be in use (it is listed under "current settings"). I do not immediately see what could be the cause of this, but perhaps you can bypass the issue by testing with debug keys on the nRF side? This is done by building with CONFIG_BT_USE_DEBUG_KEYS=y.