Bluetooth LE Security Manager Protocol Support

[takawata]

Summary

This code will add BLE Security Manager Protocol(SMP) support.
This will enable userland to create SMP connection and wait connection for underlying HCI connection to be encrypted.
To create SMP connection, set sockaddr_l2cap::l2cap_cid member as NG_L2CAP_SMP_CID.
To wait until HCI connection encrypted, do following:
enc = 1;
setsockopt( s, SOL_L2CAP, SO_L2CAP_ENCRYPTED, &enc, sizeof(enc));

Some example is in http://www.init-main.com/blesmpexample.tar.gz

[emax]

please see comments. otherwise looks good on first read. thank you for your work!

sys/netgraph/bluetooth/socket/ng_btsocket_l2cap.c

1736 ↗

(On Diff #9625)

can you please remove this printf() or change it to one of the log macros?

2339 ↗

(On Diff #9625)

i think this is cut and paste typo. it should read sizeof(pcb->need_encrypt), imo

2387 ↗

(On Diff #9625)

do you think this should check socket state? basically, if connection is already established, i think, it should refuse to change encryption. otherwise it might give an impression that encryption can be turned on/off while connection is established.

[takawata]

Reflecting the comment.

Thank you for your comment.
I corrected the problems.
Remove printf and check pcb state before updating need_encrypt and on encryption change.

[takawata]

Oops! unneeded code included.

[emax]

thank you for your work!