6.4 Sniffing the Pairing Procedure of a Connection

This allows the user to observe an encrypted connection between paired devices by monitoring the pairing procedure.

Note: If the board running in the Microchip RF Sniffer firmware is reset, stored bond information will be lost.
The following are the steps for monitoring the pairing process within a connection:
  1. Run the Bluetooth Low Energy Sniffer (if not already running).
  2. Choose the device from the list of devices.
  3. Input the pairing credentials.

The procedure will vary based on the encryption type.

For connections using just works method as legacy pairing:
  1. Begin the pairing process between the devices if it does not initiate automatically.
For connections that utilize traditional pairing with a passkey:
  1. Start the pairing process between the devices if it does not initiate automatically.
  2. Choose Legacy Passkey as the input key and input the 6-digit passkey shown on either the central or the peripheral into the Wireshark input field, then press <Enter>.
  3. Input the passkey into the alternate device.
For connections that utilize legacy pairing with OOB:
  1. Before the devices start the pairing process, choose legacy OOB data as the input key. Then, input the OOB key in big-endian, hexadecimal format with a leading 0x into the designated input field in Wireshark, then press <Enter>.
  2. Now, establish a connection between the central and the peripheral devices. If the pairing does not initiate automatically, the user needs to manually start it.
To establish connections using LE secure connections in the Debug mode:
  1. Activate the Secure Connections Debug mode on either one or both devices.
  2. If pairing does not start automatically, initiate it manually.
  3. In the Debug mode, the connection utilizes the debug keys as outlined in the Bluetooth Core Specification. The Bluetooth Low Energy Sniffer employs these same keys to decipher the encrypted packets.
For connections that utilize LE secure connections with a private key:
  1. Before initiating the pairing process between devices, choose SC Private Key as the input key.
  2. Then, input the device's 32-byte DiffieHellman private key in big-endian, hexadecimal format with a leading 0x into the Wireshark input field.
  3. If pairing does not start automatically, initiate it manually.