Bluetooth: Reject connection with the device which has same BD_ADDR
authorLee, Chun-Yi <jlee@suse.com>
Sun, 1 Oct 2023 08:59:58 +0000 (16:59 +0800)
committerLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Wed, 11 Oct 2023 18:16:24 +0000 (11:16 -0700)
commit1ffc6f8cc33268731fcf9629fc4438f6db1191fc
tree08598d4f92845b6891503d83906454491b7c0dff
parent33155c4aae5260475def6f7438e4e35564f4f3ba
Bluetooth: Reject connection with the device which has same BD_ADDR

This change is used to relieve CVE-2020-26555. The description of
the CVE:

Bluetooth legacy BR/EDR PIN code pairing in Bluetooth Core Specification
1.0B through 5.2 may permit an unauthenticated nearby device to spoof
the BD_ADDR of the peer device to complete pairing without knowledge
of the PIN. [1]

The detail of this attack is in IEEE paper:
BlueMirror: Reflections on Bluetooth Pairing and Provisioning Protocols
[2]

It's a reflection attack. The paper mentioned that attacker can induce
the attacked target to generate null link key (zero key) without PIN
code. In BR/EDR, the key generation is actually handled in the controller
which is below HCI.

A condition of this attack is that attacker should change the
BR_ADDR of his hacking device (Host B) to equal to the BR_ADDR with
the target device being attacked (Host A).

Thus, we reject the connection with device which has same BD_ADDR
both on HCI_Create_Connection and HCI_Connection_Request to prevent
the attack. A similar implementation also shows in btstack project.
[3][4]

Cc: stable@vger.kernel.org
Link: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26555
Link: https://ieeexplore.ieee.org/abstract/document/9474325/authors#authors
Link: https://github.com/bluekitchen/btstack/blob/master/src/hci.c#L3523
Link: https://github.com/bluekitchen/btstack/blob/master/src/hci.c#L7297
Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
net/bluetooth/hci_conn.c
net/bluetooth/hci_event.c