OBEX Push without pairing

I am writing an applications that, among other things, sends an OBEX Push to a device (e.g. a mobile phone). This is working fine, except for one thing: whenever I send something to the device, the first time it always asks for the PIN. I have seen that, for example, kbluetooth (the KDE Bluetooth framework) and Impronto can send a file without pairing first. How can I do that?

I am sure that I am missing something, but still have not found what. In my application, I call to socket(), bind() to a local address (BDADDR_ANY) and then connect(). It is at the connect stage that the pairing takes place. I have been following the code of kbluetooth and all I can see is that I am doing essentially the same.

Hi Pedro,

Quoted 4 lines

I am writing an applications that, among other things, sends an OBEX Push to a device (e.g. a mobile phone). This is working fine, except for one thing: whenever I send something to the device, the first time it always asks for the PIN. I have seen that, for example, kbluetooth (the KDE Bluetooth framework) and Impronto can send a file without pairing first. How can I do that?

I am sure that I am missing something, but still have not found what. In my application, I call to socket(), bind() to a local address (BDADDR_ANY) and then connect(). It is at the connect stage that the pairing takes place. I have been following the code of kbluetooth and all I can see is that I am doing essentially the same.

it seems that your device is working in security mode 3 and then actually every ACL connection requests the authentication. The simple answer is to use security mode 1/2.

Quoted 4 lines

it seems that your device is working in security mode 3 and then actually every ACL connection requests the authentication. The simple answer is to use security mode 1/2.

Thank you for your fast answer.

I am not quite sure about the security mode the device is. How can I get it? In any case, I have executed (as root):

$ hciconfig hci0 noencrypt
$ hciconfig hci0 noauth

but still no success. With the same computer and configuration and as a normal user, if I send a file from KDE using kbtobexclient, it works as expected (no PIN requested, just the confirmation for receiving the message), so I believe that there is some other things to do. I guess that it should be a library call or somthing similar. Any suggestions?

but still no success. With the same computer and configuration and as a normal user, if I send a file from KDE using kbtobexclient, it works as expected (no PIN requested, just the confirmation for receiving the message), so I believe that there is some other things to do. I guess that it should be a library call or somthing similar. Any suggestions?

Quoted 6 lines · Pedro Monjo Florit

but still no success. With the same computer and configuration and as a normal user, if I send a file from KDE using kbtobexclient, it works as expected (no PIN requested, just the confirmation for receiving the message), so I believe that there is some other things to do. I guess that it should be a library call or somthing similar. Any suggestions?

Are you sure that you are connecting to the rfcomm channel of the obex push service? All others require authentication usually. Maybe you should have a look at hcidump's output to see the difference and at which point the phone is requesting authentication.

Fred