Android bluetooth encryption technique

I want to set the encryption key size for Bluetooth in Android, but not able to find the files where the exact encryption happens. I have seen that BluetoothSocket class does take "encryptio开发者_Python百科n" as a boolean argument in constructor, but when I followed it to the JNI layer, found that it just makes system call of "setSocketOpt" . But in kernel code i was not able to find the place where its happening.

If anyone have idea where the actual encryption happens and what is the key size used for encryption then please answer.

Encryption key size is set by the LMP layer. So, you will not be able to access it at the OS level (Host level). This is done in the Firmware (Controller level).