Introduce a limited privacy mode indicated by value 0x02 to the mgmt
Set Privacy command.

With value 0x02 the kernel will use privacy mode with a resolvable
private address. In case the controller is bondable and discoverable
the identity address will be used.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Minor fix to not do the memset until the variable it clears is
actually used.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When we're doing background scanning and connection attempts it's
possible we timeout trying to connect and go back to scanning again.
The timeout triggers a HCI_LE_Create_Connection_Cancel which will
trigger a Connection Complete with "Unknown Connection Identifier"
error status. Since we go back to scanning this isn't really a failure
and shouldn't be presented as such to user space through mgmt.

The exception to this is if the connection attempt was due to an
explicit request on an L2CAP socket (indicated by
params->explicit_connect being true). Since the socket will get an
error it's consistent to also notify the failure on mgmt in this case.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

All LE connections are now triggered through a preceding passive scan
and waiting for a connectable advertising report. This means we've got
the best possible guarantee that the device is within range and should
be able to request the controller to perform continuous scanning. This
way we minimize the risk that we miss out on any advertising packets.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.3+

This paves the way for eventually performing advertising changes
through the hdev->req_workqueue. Some new APIs need to be exposed from
mgmt.c to hci_request.c and vice-versa, but many of them will go away
once hdev->req_workqueue gets used.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The conn_unfinished variable makes the entire logic of
hci_connect_le() rather confusing. By restructuring and clarifying the
logic we can actually remove the conn_unfinished variable and still
keep the same behavior.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This helps simplify the logic in further patches (less cleanups to do
in this failure branch).
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The hci_connect_le_scan() is (as the name implies) a master/central
role API, so it makes no sense in passing a role parameter to it. At
the same time this patch also fixes the direct advertising support for
LE L2CAP sockets where we now call the more appropriate hci_le_connect()
API if slave/peripheral role is desired.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Since explicit connect requests are also a sub-category of passive
scan updates, run them through the same workqueue as the other passive
scan changes.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

It's not obvious why schedule_work is used instead of queue_work. Add
a comment explaining why.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

There are a few places that don't explicitly check the connection
state before calling hci_disconnect(). To make this API do the right
thing take advantage of the new hci_abort_conn() API and also make
sure to only read the clock offset if we're really connected.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Convert the various places mapping connection state to
disconnect/cancel HCI command to use the new hci_abort_conn helper
API.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

There's only one user of this helper which can be replaces with a call
to hci_pend_le_action_lookup() and a check for params->explicit_connect.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The hci_le_create_connection_cancel() function needs to use the hdev
pointer in many places so add a variable for it to avoid the need to
dereference the hci_conn every time.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Use the new hci_conn_hash_lookup_le() API to look up LE connections.
This way we're guaranteed exact matches that also take into account
the address type.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The hci_conn objects don't have a dedicated lock themselves but rely
on the caller to hold the hci_dev lock for most types of access. The
hci_conn_timeout() function has so far sent certain HCI commands based
on the hci_conn state which has been possible without holding the
hci_dev lock.

The recent changes to do LE scanning before connect attempts added
even more operations to hci_conn and hci_dev from hci_conn_timeout,
thereby exposing potential race conditions with the hci_dev and
hci_conn states.

As an example of such a race, here there's a timeout but an
l2cap_sock_connect() call manages to race with the cleanup routine:

[Oct21 08:14] l2cap_chan_timeout: chan ee4b12c0 state BT_CONNECT
[  +0.000004] l2cap_chan_close: chan ee4b12c0 state BT_CONNECT
[  +0.000002] l2cap_chan_del: chan ee4b12c0, conn f3141580, err 111, state BT_CONNECT
[  +0.000002] l2cap_sock_teardown_cb: chan ee4b12c0 state BT_CONNECT
[  +0.000005] l2cap_chan_put: chan ee4b12c0 orig refcnt 4
[  +0.000010] hci_conn_drop: hcon f53d56e0 orig refcnt 1
[  +0.000013] l2cap_chan_put: chan ee4b12c0 orig refcnt 3
[  +0.000063] hci_conn_timeout: hcon f53d56e0 state BT_CONNECT
[  +0.000049] hci_conn_params_del: addr ee:0d:30:09:53:1f (type 1)
[  +0.000002] hci_chan_list_flush: hcon f53d56e0
[  +0.000001] hci_chan_del: hci0 hcon f53d56e0 chan f4e7ccc0
[  +0.004528] l2cap_sock_create: sock e708fc00
[  +0.000023] l2cap_chan_create: chan ee4b1770
[  +0.000001] l2cap_chan_hold: chan ee4b1770 orig refcnt 1
[  +0.000002] l2cap_sock_init: sk ee4b3390
[  +0.000029] l2cap_sock_bind: sk ee4b3390
[  +0.000010] l2cap_sock_setsockopt: sk ee4b3390
[  +0.000037] l2cap_sock_connect: sk ee4b3390
[  +0.000002] l2cap_chan_connect: 00:02:72:d9:e5:8b -> ee:0d:30:09:53:1f (type 2) psm 0x00
[  +0.000002] hci_get_route: 00:02:72:d9:e5:8b -> ee:0d:30:09:53:1f
[  +0.000001] hci_dev_hold: hci0 orig refcnt 8
[  +0.000003] hci_conn_hold: hcon f53d56e0 orig refcnt 0

Above the l2cap_chan_connect() shouldn't have been able to reach the
hci_conn f53d56e0 anymore but since hci_conn_timeout didn't do proper
locking that's not the case. The end result is a reference to hci_conn
that's not in the conn_hash list, resulting in list corruption when
trying to remove it later:

[Oct21 08:15] l2cap_chan_timeout: chan ee4b1770 state BT_CONNECT
[  +0.000004] l2cap_chan_close: chan ee4b1770 state BT_CONNECT
[  +0.000003] l2cap_chan_del: chan ee4b1770, conn f3141580, err 111, state BT_CONNECT
[  +0.000001] l2cap_sock_teardown_cb: chan ee4b1770 state BT_CONNECT
[  +0.000005] l2cap_chan_put: chan ee4b1770 orig refcnt 4
[  +0.000002] hci_conn_drop: hcon f53d56e0 orig refcnt 1
[  +0.000015] l2cap_chan_put: chan ee4b1770 orig refcnt 3
[  +0.000038] hci_conn_timeout: hcon f53d56e0 state BT_CONNECT
[  +0.000003] hci_chan_list_flush: hcon f53d56e0
[  +0.000002] hci_conn_hash_del: hci0 hcon f53d56e0
[  +0.000001] ------------[ cut here ]------------
[  +0.000461] WARNING: CPU: 0 PID: 1782 at lib/list_debug.c:56 __list_del_entry+0x3f/0x71()
[  +0.000839] list_del corruption, f53d56e0->prev is LIST_POISON2 (00000200)

The necessary fix is unfortunately more complicated than just adding
hci_dev_lock/unlock calls to the hci_conn_timeout() call path.
Particularly, the hci_conn_del() API, which expects the hci_dev lock to
be held, performs a cancel_delayed_work_sync(&hcon->disc_work) which
would lead to a deadlock if the hci_conn_timeout() call path tries to
acquire the same lock.

This patch solves the problem by deferring the cleanup work to a
separate work callback. To protect against the hci_dev or hci_conn
going away meanwhile temporary references are taken with the help of
hci_dev_hold() and hci_conn_get().
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.3

This patch makes sure that conn_params that were created just for
explicit_connect, will get properly deleted during cleanup.
Signed-off-by: NJakub Pawlowski <jpawlowski@google.com>
Acked-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

After clearing the params->explicit_connect variable the parameters
may need to be either added back to the right list or potentially left
absent from both the le_reports and the le_conns lists.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

We can't use hci_explicit_connect_lookup() since that would only cover
explicit connections, leaving normal reconnections completely
untouched. Not using it in turn means leaving out entries in
pend_le_reports.

To fix this and simplify the logic move conn params from the reports
list to the pend_le_conns list for the duration of an explicit
connect. Once the connect is complete move the params back to the
pend_le_reports list. This also means that the explicit connect lookup
function only needs to look into the pend_le_conns list.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The code should never directly call hci_conn_hash_del since many
cleanup & reference counting updates would be lost. Normally
hci_conn_del is the right thing to do, but in the case of a connection
doing LE scanning this could cause a deadlock due to doing a
cancel_delayed_work_sync() on the same work callback that we were
called from.

Connections in the LE scanning state actually need very little cleanup
- just a small subset of hci_conn_del. To solve the issue, refactor
out these essential pieces into a new hci_conn_cleanup() function and
call that from the two necessary places.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When disable/enable scan command is issued twice, some controllers
will return an error for the second request, i.e. requests with this
command will fail on some controllers, and succeed on others.

This patch makes sure that unnecessary scan disable/enable commands
are not issued.

When adding device to the auto connect whitelist when there is pending
connect attempt, there is no need to update scan.

hci_connect_le_scan_cleanup is conditionally executing
hci_conn_params_del, that is calling hci_update_background_scan. Make
the other case also update scan, and remove reduntand call from
hci_connect_le_scan_remove.

When stopping interleaved discovery the state should be set to stopped
only when both LE scanning and discovery has stopped.
Signed-off-by: NJakub Pawlowski <jpawlowski@google.com>
Acked-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Currently, when trying to connect to already paired device that just
rotated its RPA MAC address, old address would be used and connection
would fail. In order to fix that, kernel must scan and receive
advertisement with fresh RPA before connecting.

This patch makes sure that when new procedure is in use, and we're stuck
in scan phase because no advertisement was received and timeout happened,
or app decided to close socket, scan whitelist gets properly cleaned up.
Signed-off-by: NJakub Pawlowski <jpawlowski@google.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Currently, when trying to connect to already paired device that just
rotated its RPA MAC address, old address would be used and connection
would fail. In order to fix that, kernel must scan and receive
advertisement with fresh RPA before connecting.

This path makes sure that after advertisement is received from device that
we try to connect to, it is properly handled in check_pending_le_conn and
trigger connect attempt.

It also modifies hci_le_connect to make sure that connect attempt will be
properly continued.
Signed-off-by: NJakub Pawlowski <jpawlowski@google.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Currently, when trying to connect to already paired device that just
rotated its RPA MAC address, old address would be used and connection
would fail. In order to fix that, kernel must scan and receive
advertisement with fresh RPA before connecting.

This patch adds hci_connect_le_scan with dependencies, new method that
will be used to connect to remote LE devices. Instead of just sending
connect request, it adds a device to whitelist. Later patches will make
use of this whitelist to send conenct request when advertisement is
received, and properly handle timeouts.
Signed-off-by: NJakub Pawlowski <jpawlowski@google.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch adds hci_lookup_le_connect method, that will be used to check
wether outgoing le connection attempt is in progress.
Signed-off-by: NJakub Pawlowski <jpawlowski@google.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The encryption key size for LTKs is supposed to be applied only at the
moment of encryption. When generating a Link Key (using LE SC) from
the LTK the full non-shortened value should be used. This patch
modifies the code to always keep the full value around and only apply
the key size when passing the value to HCI.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Instead of manually coding clear_bit on hdev->dev_flags all the time,
use hci_dev_clear_flag helper macro.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Instead of manually coding set_bit on hdev->dev_flags all the time,
use hci_dev_set_flag helper macro.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Instead of manually coding test_bit on hdev->dev_flags all the time,
use hci_dev_test_flag helper macro.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

This patch moves all the disconn_cfm callbacks to be based on the hci_cb
list. This means making l2cap_disconn_cfm private to l2cap_core.c and
sco_conn_cb private to sco.c respectively. Since the hci_conn type
filtering isn't done any more on the wrapper level the callbacks
themselves need to check that they were passed a relevant type of
connection.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch moves all the connect_cfm callbacks to be based on the hci_cb
list. This means making l2cap_connect_cfm private to l2cap_core.c and
sco_connect_cb private to sco.c respectively. Since the hci_conn type
filtering isn't done any more on the wrapper level the callbacks
themselves need to check that they were passed a relevant type of
connection.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

With this patch -EOPNOTSUPP will be returned by hci_connect_acl for LE
only controllers. If it is dual device with disabled BREDR -ECONNREFUSED
will be returned
Signed-off-by: NLukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Kernel gives possibility to enable/disable LE host support.
There is flag HCI_LE_ENABLED which is set when this support is enabled
and some parts of the code checks this flag e.g. SMP
However it is still possible to make LE connection if LE Host support is
disabled, what might be confused for remote device.
This patch makes sure that kernel will not send HCI LE Create Connection
if LE HOST support is not enabled.
Signed-off-by: NLukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Remove the function hci_conn_change_link_key() that is not used anywhere.

This was partially found by using a static code analysis program called
cppcheck.
Signed-off-by: NRickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

When hci_req_run() calls its provided complete function and one of the
HCI commands in the sequence fails, then provide the opcode of failing
command. In case of success HCI_OP_NOP is provided since all commands
completed.

This patch fixes the prototype of hci_req_complete_t and all its users.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

For every internal representation of a Bluetooth connection which is
identified by hci_conn, create a debugfs directory with the handle
number as directory name.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

None of the hci_request related things in net/bluetooth/hci_core.h are
needed anywhere outside of the core bluetooth module. This patch creates
a new net/bluetooth/hci_request.c file with its corresponding h-file and
moves the functionality there from hci_core.c and hci_core.h.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When the host decides to use a non-resolvable private address, it
must ensure that this generated address does not match the public
address of the controller. Add an extra check to ensure this required
behavior.

In addition rename the variable from urpa to nrpa and fix all of the
comments in the code that use the term unresolvable instead of the
term non-resolvable as used in the Bluetooth specification.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

When we create the hci_conn object we should properly initialize the
RSSI to HCI_RSSI_INVALID.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

These days we allow simultaneous LE scanning and advertising. Checking
for whether advertising is enabled or not is therefore not a reliable
way to determine whether directed advertising was used to trigger the
connection creation. The appropriate place to check (instead of the hdev
context) is the connection role that's stored in the hci_conn. This
patch fixes such a check in le_conn_timeout() which could otherwise lead
to incorrect HCI commands being sent.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.16.x