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196 Commits (81055e584f9d743cb13dc7944923d817c20f089d)

Author SHA1 Message Date
Johan Hedberg 09da1f3463 Bluetooth: Fix redundant encryption request for reauthentication
When we're performing reauthentication (in order to elevate the
security level from an unauthenticated key to an authenticated one) we
do not need to issue any encryption command once authentication
completes. Since the trigger for the encryption HCI command is the
ENCRYPT_PEND flag this flag should not be set in this scenario.
Instead, the REAUTH_PEND flag takes care of all necessary steps for
reauthentication.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
2014-04-25 09:47:15 +03:00
Marcel Holtmann 40b552aa5a Bluetooth: Enforce strict Secure Connections Only mode security
In Secure Connections Only mode, it is required that Secure Connections
is used for pairing and that the link key is encrypted with AES-CCM using
a P-256 authenticated combination key. If this is not the case, then new
connection shall be refused or existing connections shall be dropped.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-03-19 23:30:32 +02:00
Joe Perches dcf4adbfdc Bluetooth: Convert uses of __constant_<foo> to <foo>
The use of __constant_<foo> has been unnecessary for quite awhile now.

Make these uses consistent with the rest of the kernel.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-03-12 11:10:17 -07:00
Johan Hedberg 81ad6fd969 Bluetooth: Remove unnecessary stop_scan_complete function
The stop_scan_complete function was used as an intermediate step before
doing the actual connection creation. Since we're using hci_request
there's no reason to have this extra function around, i.e. we can simply
put both HCI commands into the same request.

The single task that the intermediate function had, i.e. indicating
discovery as stopped is now taken care of by a new
HCI_LE_SCAN_INTERRUPTED flag which allows us to do the discovery state
update when the stop scan command completes.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-28 10:28:17 -08:00
Johan Hedberg 317ac8cb3f Bluetooth: Fix trying to disable scanning twice
The discovery process has a timer for disabling scanning, however
scanning might be disabled through other means too like the auto-connect
process.  We should therefore ensure that the timer is never active
after sending a HCI command to disable scanning.

There was some existing code in stop_scan_complete trying to avoid the
timer when a connect request interrupts a discovery procedure, but the
other way around was not covered. This patch covers both scenarios by
canceling the timer as soon as we get a successful command complete for
the disabling HCI command.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-28 10:28:16 -08:00
Johan Hedberg 9489eca4ab Bluetooth: Add timeout for LE connection attempts
LE connection attempts do not have a controller side timeout in the same
way as BR/EDR has (in form of the page timeout). Since we always do
scanning before initiating connections the attempts are always expected
to succeed in some reasonable time.

This patch adds a timer which forces a cancellation of the connection
attempt within 20 seconds if it has not been successful by then. This
way we e.g. ensure that mgmt_pair_device times out eventually and gives
an error response.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-28 07:56:42 -08:00
Johan Hedberg b46e003089 Bluetooth: Fix updating connection state to BT_CONNECT too early
We shouldn't update the hci_conn state to BT_CONNECT until the moment
that we're ready to send the initiating HCI command for it. If the
connection has the BT_CONNECT state too early the code responsible for
updating the local random address may incorrectly think there's a
pending connection in progress and refuse to update the address.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-28 07:53:07 -08:00
Marcel Holtmann fe39c7b2da Bluetooth: Use __le64 type for LE random numbers
The random numbers in Bluetooth Low Energy are 64-bit numbers and should
also be little endian since the HCI specification is little endian.

Change the whole Low Energy pairing to use __le64 instead of a byte
array.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-28 12:36:04 +02:00
Andre Guedes a4790dbd43 Bluetooth: Introduce LE auto connection infrastructure
This patch introduces the LE auto connection infrastructure which
will be used to implement the LE auto connection options.

In summary, the auto connection mechanism works as follows: Once the
first pending LE connection is created, the background scanning is
started. When the target device is found in range, the kernel
autonomously starts the connection attempt. If connection is
established successfully, that pending LE connection is deleted and
the background is stopped.

To achieve that, this patch introduces the hci_update_background_scan()
which controls the background scanning state. This function starts or
stops the background scanning based on the hdev->pend_le_conns list. If
there is no pending LE connection, the background scanning is stopped.
Otherwise, we start the background scanning.

Then, every time a pending LE connection is added we call hci_update_
background_scan() so the background scanning is started (in case it is
not already running). Likewise, every time a pending LE connection is
deleted we call hci_update_background_scan() so the background scanning
is stopped (in case this was the last pending LE connection) or it is
started again (in case we have more pending LE connections). Finally,
we also call hci_update_background_scan() in hci_le_conn_failed() so
the background scan is restarted in case the connection establishment
fails. This way the background scanning keeps running until all pending
LE connection are established.

At this point, resolvable addresses are not support by this
infrastructure. The proper support is added in upcoming patches.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-26 19:41:34 -08:00
Andre Guedes 6f77d8c757 Bluetooth: Move address type conversion to outside hci_connect_le
This patch moves address type conversion (L2CAP address type to HCI
address type) to outside hci_connect_le. This way, we avoid back and
forth address type conversion in a comming patch.

So hci_connect_le() now expects 'dst_type' parameter in HCI address
type convention.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-26 19:41:34 -08:00
Andre Guedes 04a6c5898e Bluetooth: Refactor HCI connection code
hci_connect() is a very simple and useless wrapper of hci_connect_acl
and hci_connect_le functions. Addtionally, all places where hci_connect
is called the link type value is passed explicitly. This way, we can
safely delete hci_connect, declare hci_connect_acl and hci_connect_le
in hci_core.h and call them directly.

No functionality is changed by this patch.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-26 19:41:34 -08:00
Andre Guedes c99ed8343c Bluetooth: Remove unused function
This patch removes hci_create_le_conn() since it is not used anymore.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-26 19:41:33 -08:00
Andre Guedes 2acf3d9066 Bluetooth: Stop scanning on LE connection
Some LE controllers don't support scanning and creating a connection
at the same time. So we should always stop scanning in order to
establish the connection.

Since we may prematurely stop the discovery procedure in favor of
the connection establishment, we should also cancel hdev->le_scan_
disable delayed work and set the discovery state to DISCOVERY_STOPPED.

This change does a small improvement since it is not mandatory the
user stops scanning before connecting anymore. Moreover, this change
is required by upcoming LE auto connection mechanism in order to work
properly with controllers that don't support background scanning and
connection establishment at the same time.

In future, we might want to do a small optimization by checking if
controller is able to scan and connect at the same time. For now,
we want the simplest approach so we always stop scanning (even if
the controller is able to carry out both operations).

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-26 19:41:33 -08:00
Andre Guedes 06c053fb54 Bluetooth: Declare le_conn_failed in hci_core.h
This patch adds the "hci_" prefix to le_conn_failed() helper and
declares it in hci_core.h so it can be reused in hci_event.c.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-26 19:41:33 -08:00
Marcel Holtmann 94b1fc92cd Bluetooth: Use unresolvable private address for active scanning
When running active scanning during LE discovery, do not reveal the own
identity to the peer devices. In case LE privacy has been enabled, then
a resolvable private address is used. If the LE privacy option is off,
then use an unresolvable private address.

The public address or static random address is never used in active
scanning anymore. This ensures that scan request are send using a
random address.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-24 08:45:58 +02:00
Johan Hedberg e26b1ffa11 Bluetooth: Fix setting correct src_type when connecting LE
This patch ensures that conn->src_type contains the same address type as
is used for initiating the connection while the connection attempt is in
progress. Once connected this value will be overwritten with the
identity address type.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-23 12:24:26 -08:00
Johan Hedberg 85030be4c5 Bluetooth: Use hci_update_random_address() when connecting LE
When we initiate LE connections we need to update the local random
address if necessary. This patch updates the LE connection creation
mechanism to use the new hci_update_random_address() function to set the
own_address_type parameter and to update the local random address if
necessary.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-23 12:24:26 -08:00
Marcel Holtmann d66c295031 Bluetooth: Use same LE min/max connection event length during update
During LE connection establishment the value 0x0000 is used for min/max
connection event length. So use the same value when the peripheral is
requesting an update of the the connection paramters.

For some reason the value 0x0001 got used in the connection update and
0x0000 in the connection creation. Using the same value for both just
makes sense.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-19 08:53:28 +02:00
Marcel Holtmann edb4b46651 Bluetooth: Fix wrong identity address during connection failures
When the connection attempt fails, the address information are not
provided in the HCI_LE_Connection_Complete event. So use the original
information from the connection to reconstruct the identity address.

This is important when a connection attempt has been made using the
identity address, but the cached resolvable random address has changed
in the meantime. The failure event needs to use the identity address
and not the resolvable random address.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-19 06:09:41 +02:00
Johan Hedberg 1ebfcc1f58 Bluetooth: Look up RPA for connection requests with Identity Address
We need to check whether there's a matching IRK and RPA when we're
requested to connect to a remote LE device based on its Identity
Address. This patch updates the hci_connect_le function to do an extra
call to hci_find_irk_by_addr and uses the RPA if it's cached. This is
particularly important once we start exposing the Identity Address to
user space instead of the RPA in events such as Device Connected and
Device Found.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-18 11:48:55 -08:00
Andre Guedes 4292f1f337 Bluetooth: Use connection parameters if any
This patch changes hci_connect_le() so it uses the connection
parameters specified for the certain device. If no parameters
were configured, we use the default values.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-13 09:51:44 +02:00
Marcel Holtmann 9cb2e030e6 Bluetooth: Include security level 4 in connections check
This check is only used for RFCOMM connections and most likely no
RFCOMM based profile will require security level 4 secure connection
security policy. In case it ever does make sure that seucrity level 4
is treated as sufficient security level.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-13 09:51:43 +02:00
Andre Guedes 9bb3c01fdb Bluetooth: Introduce le_conn_failed() helper
This patch moves connection attempt failure code to its own function
so it can be reused in the next patch.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-13 09:51:41 +02:00
Andre Guedes 1e406eefbe Bluetooth: Save connection interval parameters in hci_conn
This patch creates two new fields in struct hci_conn to save the
minimum and maximum connection interval values used to establish
the connection this object represents.

This change is required in order to know what parameters the
connection is currently using.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-13 09:51:41 +02:00
Marcel Holtmann 7b5a9241b7 Bluetooth: Introduce requirements for security level 4
The security level 4 is a new strong security requirement that is based
around 128-bit equivalent strength for link and encryption keys required
using FIPS approved algorithms. Which means that E0, SAFER+ and P-192
are not allowed. Only connections created with P-256 resulting from
using Secure Connections support are allowed.

This security level needs to be enforced when Secure Connection Only
mode is enabled for a controller or a service requires FIPS compliant
strong security. Currently it is not possible to enable either of
these two cases. This patch just puts in the foundation for being
able to handle security level 4 in the future.

It should be noted that devices or services with security level 4
requirement can only communicate using Bluetooth 4.1 controllers
with support for Secure Connections. There is no backward compatibilty
if used with older hardware.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-13 09:51:35 +02:00
Marcel Holtmann 66138ce8e5 Bluetooth: Add support for handling P-256 derived link keys
Before being able to enable Secure Connections support, the core needs
to know on how to handle P-256 derived link keys. The difference between
authenticated and unauthenticated P-256 derived link keys is the same as
its P-192 counter parts.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-13 09:51:32 +02:00
Marcel Holtmann 11015c7903 Bluetooth: Add definitions for new link key types
With the introduction of Secure Connections, the list of link key types
got extended by P-256 versions of authenticated and unauthenticated
link keys.

To avoid any confusion the previous authenticated and unauthenticated
link key types got ammended with a P912 postfix. And the two new keys
have a P256 postfix now. Existing code using the previous definitions
has been adjusted.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-02-13 09:51:31 +02:00
Marcel Holtmann 4e70c7e71c Bluetooth: Expose debugfs settings for LE connection interval
For testing purposes expose the default LE connection interval values
via debugfs.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-19 18:56:54 +03:00
Marcel Holtmann 79830f66e3 Bluetooth: Select the own address type during initial setup phase
The own address type is based on the fact if the controller has
a public address or not. This means that this detail can be just
configured once during setup phase.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-19 16:28:06 +03:00
Johan Hedberg a74a84f696 Bluetooth: Convert idle timer to use delayed work
There is no need to use a timer since the entire Bluetooth subsystem
runs using workqueues these days.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-16 09:12:13 -07:00
Johan Hedberg 7bc18d9d3d Bluetooth: Convert auto accept timer to use delayed work
Since the entire Bluetooth subsystem runs in workqueues these days there
is no need to use a timer for deferring work.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-16 09:12:12 -07:00
Marcel Holtmann 662e8820f3 Bluetooth: Store source address of HCI connections
The source addressed was based on the public address of the HCI device,
but with LE connections this not always the case. For example single
mode LE-only controllers would use a static random address. And this
address is configured by userspace.

To not complicate the lookup of what kind of address is in use, store
the correct source address for each HCI connection.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-13 17:47:37 +03:00
Marcel Holtmann e7c4096e16 Bluetooth: Store the source address type of LE connections
When establishing LE connections, it is possible to use a public
address (if available) or a random address. The type of address
is only known when creating connections, so make sure it is
stored in hci_conn structure.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-13 17:46:31 +03:00
Marcel Holtmann 79d95a19a4 Bluetooth: Remove pointless bdaddr_to_le() helper function
The bdaddr_to_le() function tries to convert the internal address
type to one that matches the HCI address type for LE. It does not
handle any address types not used by LE and in the end just make
the code a lot harder to read.

So instead of just hiding behind a magic function, just convert
the internal address type where it needs to be converted. And it
turns out that these are only two cases anyway. One when creating
new LE connections and the other when loading the long term keys.
In both cases this makes it more clear on what it going on.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-13 17:45:55 +03:00
Marcel Holtmann bef64738e3 Bluetooth: Make LE scan interval and window a controller option
The scan interval and window for LE passive scanning and connection
establishment should be configurable on a per controller basis. So
introduce a setting that later on will allow modifying it.

This setting does not affect LE active scanning during device
discovery phase. As long as that phase uses interleaved discovery,
it will continuously scan.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-11 18:18:11 +02:00
Marcel Holtmann ac4b723661 Bluetooth: Move smp.h header file into net/bluetooth/
The smp.h header file is only used internally by the bluetooth.ko
module and is not a public API. So make it local to the core
Bluetooth module.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-11 00:10:07 +02:00
Marcel Holtmann 7024728ee5 Bluetooth: Move a2mp.h header file into net/bluetooth/
The a2mp.h header file is only used internally by the bluetooth.ko
module and is not a public API. So make it local to the core
Bluetooth module.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-11 00:10:05 +02:00
Andre Guedes 620ad5219c Bluetooth: Refactor hci_connect_le
This patch does some code refactoring in hci_connect_le() by moving
the exception code into if statements and letting the main flow in
first level of function scope. It also adds extra comments to improve
the code readability.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-10 01:30:18 -07:00
Andre Guedes 1d399ae5c7 Bluetooth: Use HCI request for LE connection
This patch introduces a new helper, which uses the HCI request
framework, for creating LE connectons. All the handling is now
done by this function so we can remove the hci_cs_le_create_conn()
event handler.

This patch also removes the old hci_le_create_connection() since
it is not used anymore.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-10 01:30:18 -07:00
Marcel Holtmann c25dfc610b Bluetooth: Use random address if public address is not available
For single mode LE-only controllers, it is possible that they come
without a public address. If a public address is not available,
then use the random address for connection establishment and
scanning.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-06 11:13:11 +02:00
Johan Hedberg f3d3444a4d Bluetooth: Rename HCI_LE_PERIPHERAL to HCI_ADVERTISING
This flag is used to indicate whether we want to have advertising
enabled or not, so give it a more suitable name.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-05 03:03:38 -07:00
Andre Guedes 46a190cbd3 Bluetooth: Initialize hci_conn fields in hci_connect_le
This patch moves some hci_conn fields initialization from hci_le_
create_connection() to hci_connect_le(). It makes more sense to
initialize these fields within the function that creates the hci_
conn object.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-03 23:07:17 -07:00
Andre Guedes f1e5d54743 Bluetooth: Rename hci_conn variable in hci_connect_le()
This patch simply rename the hci_conn variable "le" to "conn"
since it is a better name.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-03 23:07:17 -07:00
Johan Hedberg 56f8790102 Bluetooth: Introduce a new HCI_BREDR_ENABLED flag
To allow treating dual-mode (BR/EDR/LE) controllers as single-mode ones
(LE-only) we want to introduce a new HCI_BREDR_ENABLED flag to track
whether BR/EDR is enabled or not (previously we simply looked at the
feature bit with lmp_bredr_enabled).

This patch add the new flag and updates the relevant places to test
against it instead of using lmp_bredr_enabled. The flag is by default
enabled when registering an adapter and only cleared if necessary once
the local features have been read during the HCI init procedure.

We cannot completely block BR/EDR usage in case user space uses raw HCI
sockets but the patch tries to block this in places where possible, such
as the various BR/EDR specific ioctls.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-10-02 03:48:28 -07:00
Marcel Holtmann af750e942e Bluetooth: Disable upper layer connections when user channel is active
When the device has the user channel flag set, it means it is driven by
an user application. In that case do not allow any connections from
L2CAP or SCO sockets.

This is the same situation as when the device has the raw flag set and
it will then return EHOSTUNREACH.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Acked-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-09-16 14:35:56 -03:00
Frédéric Dalleau 2dea632f9a Bluetooth: Add SCO connection fallback
When initiating a transparent eSCO connection, make use of T2 settings
at first try. T2 is the recommended settings from HFP 1.6 WideBand
Speech. Upon connection failure, try T1 settings.

When CVSD is requested and eSCO is supported, try to establish eSCO
connection using S3 settings. If it fails, fallback in sequence to S2,
S1, D1, D0 settings.

To know which setting should be used, conn->attempt is used. It
indicates the currently ongoing SCO connection attempt and can be used
as the index for the fallback settings table.

These setting and the fallback order are described in Bluetooth HFP 1.6
specification p. 101.

Signed-off-by: Frédéric Dalleau <frederic.dalleau@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-08-21 16:47:13 +02:00
Frédéric Dalleau 10c62ddc6f Bluetooth: Parameters for outgoing SCO connections
In order to establish a transparent SCO connection, the correct settings
must be specified in the Setup Synchronous Connection request. For that,
a setting field is added to ACL connection data to set up the desired
parameters. The patch also removes usage of hdev->voice_setting in CVSD
connection and makes use of T2 parameters for transparent data.

Signed-off-by: Frédéric Dalleau <frederic.dalleau@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-08-21 16:47:11 +02:00
Frédéric Dalleau e660ed6c70 Bluetooth: Use hci_connect_sco directly
hci_connect is a super function for connecting hci protocols. But the
voice_setting parameter (introduced in subsequent patches) is only
needed by SCO and security requirements are not needed for SCO channels.
Thus, it makes sense to have a separate function for SCO.

Signed-off-by: Frédéric Dalleau <frederic.dalleau@linux.intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-08-21 16:47:08 +02:00
David Herrmann 8d12356f33 Bluetooth: introduce hci_conn ref-counting
We currently do not allow using hci_conn from outside of HCI-core.
However, several other users could make great use of it. This includes
HIDP, rfcomm and all other sub-protocols that rely on an active
connection.

Hence, we now introduce hci_conn ref-counting. We currently never call
get_device(). put_device() is exclusively used in hci_conn_del_sysfs().
Hence, we currently never have a greater device-refcnt than 1.
Therefore, it is safe to move the put_device() call from
hci_conn_del_sysfs() to hci_conn_del() (it's the only caller). In fact,
this even fixes a "use-after-free" bug as we access hci_conn after calling
hci_conn_del_sysfs() in hci_conn_del().

From now on we can add references to hci_conn objects in other layers
(like l2cap_sock, HIDP, rfcomm, ...) and grab a reference via
hci_conn_get(). This does _not_ guarantee, that the connection is still
alive. But, this isn't what we want. We can simply lock the hci_conn
device and use "device_is_registered(hci_conn->dev)" to test that.
However, this is hardly necessary as outside users should never rely on
the HCI connection to be alive, anyway. Instead, they should solely rely
on the device-object to be available.
But if sub-devices want the hci_conn object as sysfs parent, they need to
be notified when the connection drops. This will be introduced in later
patches with l2cap_users.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-04-17 02:45:22 -03:00
David Herrmann fc225c3f5d Bluetooth: remove unneeded hci_conn_hold/put_device()
hci_conn_hold/put_device() is used to control when hci_conn->dev is no
longer needed and can be deleted from the system. Lets first look how they
are currently used throughout the code (excluding HIDP!).

All code that uses hci_conn_hold_device() looks like this:
    ...
    hci_conn_hold_device();
    hci_conn_add_sysfs();
    ...
On the other side, hci_conn_put_device() is exclusively used in
hci_conn_del().

So, considering that hci_conn_del() must not be called twice (which would
fail horribly), we know that hci_conn_put_device() is only called _once_
(which is in hci_conn_del()).
On the other hand, hci_conn_add_sysfs() must not be called twice, either
(it would call device_add twice, which breaks the device, see
drivers/base/core.c). So we know that hci_conn_hold_device() is also
called only once (it's only called directly before hci_conn_add_sysfs()).

So hold and put are known to be called only once. That means we can safely
remove them and directly call hci_conn_del_sysfs() in hci_conn_del().

But there is one issue left: HIDP also uses hci_conn_hold/put_device().
However, this case can be ignored and simply removed as it is totally
broken. The issue is, the only thing HIDP delays with
hci_conn_hold_device() is the removal of the hci_conn->dev from sysfs.
But, the hci_conn device has no mechanism to get notified when its own
parent (hci_dev) gets removed from sysfs. hci_dev_hold/put() does _not_
control when it is removed but only when the device object is created
and destroyed.
And hci_dev calls hci_conn_flush_*() when it removes itself from sysfs,
which itself causes hci_conn_del() to be called, but it does _not_ cause
hci_conn_del_sysfs() to be called, which is wrong.

Hence, we fix it to call hci_conn_del_sysfs() in hci_conn_del(). This
guarantees that a hci_conn object is removed from sysfs _before_ its
parent hci_dev is removed.

The changes to HIDP look scary, wrong and broken. However, if you look at
the HIDP session management, you will notice they're already broken in the
exact _same_ way (ever tried "unplugging" HIDP devices? Breaks _all_ the
time).
So this patch only makes HIDP look _scary_ and _obviously broken_. It does
not break HIDP itself, it already is!

See later patches in this series which fix HIDP to use proper
session-management.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-04-17 02:38:36 -03:00