commit 5981a8821b upstream.
This patch fixes authentication failure on LE link re-connection when
BlueZ acts as slave (peripheral). LTK is removed from the internal list
after its first use causing PIN or Key missing reply when re-connecting
the link. The LE Long Term Key Request event indicates that the master
is attempting to encrypt or re-encrypt the link.
Pre-condition: BlueZ host paired and running as slave.
How to reproduce(master):
1) Establish an ACL LE encrypted link
2) Disconnect the link
3) Try to re-establish the ACL LE encrypted link (fails)
> HCI Event: LE Meta Event (0x3e) plen 19
LE Connection Complete (0x01)
Status: Success (0x00)
Handle: 64
Role: Slave (0x01)
...
@ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000
> HCI Event: LE Meta Event (0x3e) plen 13
LE Long Term Key Request (0x05)
Handle: 64
Random number: 875be18439d9aa37
Encryption diversifier: 0x76ed
< HCI Command: LE Long Term Key Request Reply (0x08|0x001a) plen 18
Handle: 64
Long term key: 2aa531db2fce9f00a0569c7d23d17409
> HCI Event: Command Complete (0x0e) plen 6
LE Long Term Key Request Reply (0x08|0x001a) ncmd 1
Status: Success (0x00)
Handle: 64
> HCI Event: Encryption Change (0x08) plen 4
Status: Success (0x00)
Handle: 64
Encryption: Enabled with AES-CCM (0x01)
...
@ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 3
< HCI Command: LE Set Advertise Enable (0x08|0x000a) plen 1
Advertising: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4
LE Set Advertise Enable (0x08|0x000a) ncmd 1
Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 19
LE Connection Complete (0x01)
Status: Success (0x00)
Handle: 64
Role: Slave (0x01)
...
@ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000
> HCI Event: LE Meta Event (0x3e) plen 13
LE Long Term Key Request (0x05)
Handle: 64
Random number: 875be18439d9aa37
Encryption diversifier: 0x76ed
< HCI Command: LE Long Term Key Request Neg Reply (0x08|0x001b) plen 2
Handle: 64
> HCI Event: Command Complete (0x0e) plen 6
LE Long Term Key Request Neg Reply (0x08|0x001b) ncmd 1
Status: Success (0x00)
Handle: 64
> HCI Event: Disconnect Complete (0x05) plen 4
Status: Success (0x00)
Handle: 64
Reason: Authentication Failure (0x05)
@ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 0
Signed-off-by: Claudio Takahasi <claudio.takahasi@openbossa.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>