Thats the problem. On Windows7, 64 bit, with the Bluetooth Stack from the USB BLE-Stick happens the following: Windows (master) initiates the connection, sends a security requierement of Bond=1, MITM=1, etc... I do´nt support MITM, so it fails with error 0x83, but the Master sends after this a second pairing request with Bond=1, MITM=0 etc..., so it decreased the security levels, starting with the highest.
But the slave does not answer anymore.
The problem is in S110 V6.0.0 til S110 V8.0.0 the same.
How can I change, that the slave dont disconnect in the given timeout? I will, that he should response all request, so that the master can determine the higest available security level.
Update.
After a lot of sniffing and playing with Android and Windows I´ve note, that the main problem is not the MITM or Bonding, is the requested Initiator Key Type.
On Android:
Sniff_android.pcapng
677 6.821182000 Master Slave SMP 37 Rcvd Pairing Request: Bonding, MITM, Initiator Key(s): LTK IRK CSRK , Responder Key(s): LTK IRK CSRK
680 6.872967000 Slave Master SMP 37 Rcvd Pairing Response: Bonding, No MITM, Initiator Key(s): IRK , Responder Key(s): LTK IRK
Thats fine. The slave answers with IRK.
On Windows: Sniff.pcapng 119 48.358824000 Master Slave SMP 37 Rcvd Pairing Request: Bonding, MITM, Initiator Key(s): LTK , Responder Key(s): LTK 122 48.377210000 Slave Master SMP 37 Rcvd Pairing Response: Bonding, No MITM, Initiator Key(s): , Responder Key(s): LTK
That goes wrong. The Slave answers with an empty Initiator Key. After this, the Master answers with : 123 48.384597000 Master Slave SMP 32 Rcvd Pairing Failed: Authentication Requirements The Slave sends one empty data block.
Then the Master repeats till timeout: 125 48.394607000 Master Slave SMP 37 Rcvd Pairing Request: Bonding, No MITM, Initiator Key(s): LTK , Responder Key(s): LTK
But no more response from the slave....
Here the disconnect event. discon_event.png
