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: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

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: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

For SMP we need the local and remote addresses (and their types) that
were used to establish the connection. These may be different from the
Identity Addresses or even the current RPA. To guarantee that we have
this information available and it is correct track these values
separately from the very beginning of the connection.

For outgoing connections we set the values as soon as we get a
successful command status for HCI_LE_Create_Connection (for which the
patch adds a command status handler function) and for incoming
connections as soon as we get a LE Connection Complete HCI event.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

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: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

When the LE white list gets changed via HCI commands make sure that
the internal storage of the white list entries gets updated.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The number of places needing the local Identity Address are starting to
grow so it's better to have a single place for the logic of determining
it. This patch adds a convenience function for getting the Identity
Address and updates the two current places needing this to use it.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

To know the real source address for incoming connections (needed e.g.
for SMP) we should store the own_address_type parameter that was used
for the last HCI_LE_Write_Advertising_Parameters command. This patch
adds a proper command complete handler for the command and stores the
address type in a new adv_addr_type variable in the hci_dev struct.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Only identity addresses are inserted into hdev->pend_le_conns. So,
in order to support resolvable private addresses in auto connection
mechanism, we should resolve the address before checking for pending
connections.

Thus, this patch adds an extra check in check_pending_le_conn() and
updates 'addr' and 'addr_type' variables before hci_pend_le_conn_
lookup().
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch introduces the LE auto connection options: HCI_AUTO_CONN_
ALWAYS and HCI_AUTO_CONN_LINK_LOSS. Their working mechanism are
described as follows:

The HCI_AUTO_CONN_ALWAYS option configures the kernel to always re-
establish the connection, no matter the reason the connection was
terminated. This feature is required by some LE profiles such as
HID over GATT, Health Thermometer and Blood Pressure. These profiles
require the host autonomously connect to the device as soon as it
enters in connectable mode (start advertising) so the device is able
to delivery notifications or indications.

The BT_AUTO_CONN_LINK_LOSS option configures the kernel to re-
establish the connection in case the connection was terminated due
to a link loss. This feature is required by the majority of LE
profiles such as Proximity, Find Me, Cycling Speed and Cadence and
Time.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

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: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

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: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Once mgmt_set_powered(off) starts doing disconnections we'll need to
care about any disconnections in mgmt.c and not just those with the
MGMT_CONNECTED flag set. Therefore, move the check into mgmt.c from
hci_event.c.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

We'll soon need to make decisions on toggling the HCI_ADVERTISING flag
based on pending mgmt_set_powered commands. Therefore, move the handling
from hci_event.c into mgmt.c.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

To be consistent with the remote address info in hci_conn we want it to
also contain the local identity address information. This patch updates
the code to copy the right values in place whenever an LE connection has
been established.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

For Bluetooth controllers with LE support, track the value of the
currently configured random address. It is important to know what
the current random address is to avoid unneeded attempts to set
a new address. This will become important when introducing the
LE privacy support in the future.

In addition expose the current configured random address via
debugfs for debugging purposes.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

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: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

When reporting connect failed events to userspace, use the address
of the connection and not the address from the HCI event.

This change is strictly speaking not needed since BR/EDR does not
have the concept of resolvable random addresses. It is more for
making the code consistent.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

When the remote device has been successfully connected, report the
identity address (public address or static random address).

Currently the address from the HCI_LE_Connection_Complete event is
used. This was no problem so far, but since now known resolvable
random addresses are converted into identities, it is important to
use the identity of the connection and not the address report by
HCI event.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Since we want user space to see and use the LE Identity Address whenever
interfacing with the kernel it makes sense to track that instead of the
real address (the two will only be different in the case of an RPA).
This patch adds the necessary updates to when an LE connection gets
established and when receiving the Identity Address from a remote
device.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When the ACL link is using P-256 authenticated combination key, mark
the link mode as HCI_LM_FIPS.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

When encryption for LE links has been enabled, it will always be use
AES-CCM encryption. In case of BR/EDR Secure Connections, the link
will also use AES-CCM encryption. In both cases track the AES-CCM
status in the connection flags.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The function already has an unlock label which means the one extra level
on indentation is not useful and just makes the code more complex. So
remove it.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

If LTK distribution happens in both directions we will have two LTKs for
the same remote device: one which is used when we're connecting as
master and another when we're connecting as slave. When looking up LTKs
from the locally stored list we shouldn't blindly return the first match
but also consider which type of key is in question. If we do not do this
we may end up selecting an incorrect encryption key for a connection.

This patch fixes the issue by always specifying to the LTK lookup
functions whether we're looking for a master or a slave key.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

It is important to know if Secure Connections support has been enabled
for a given remote device. The information is provided in the remote
host features page. So track this information and provide a simple
helper function to extract the status.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

When Secure Connections has been enabled it is possible to provide P-192
and/or P-256 data during the pairing process. The internal out-of-band
credentials storage has been extended to also hold P-256 data.

Initially the P-256 data will be empty and with Secure Connections enabled
no P-256 data will be provided. This is according to the specification
since it might be possible that the remote side did not provide either
of the out-of-band credentials.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

For Secure Connections support and the usage of out-of-band pairing,
it is needed to read the P-256 hash and randomizer or P-192 hash and
randomizer. This change will read P-192 data when Secure Connections
is disabled and P-192 and P-256 data when it is enabled.

The difference is between using HCI Read Local OOB Data and using the
new HCI Read Local OOB Extended Data command. The first one has been
introduced with Bluetooth 2.1 and returns only the P-192 data.

< HCI Command: Read Local OOB Data (0x03|0x0057) plen 0
> HCI Event: Command Complete (0x0e) plen 36
      Read Local OOB Data (0x03|0x0057) ncmd 1
        Status: Success (0x00)
        Hash C from P-192: 975a59baa1c4eee391477cb410b23e6d
        Randomizer R with P-192: 9ee63b7dec411d3b467c5ae446df7f7d

The second command has been introduced with Bluetooth 4.1 and will
return P-192 and P-256 data.

< HCI Command: Read Local OOB Extended Data (0x03|0x007d) plen 0
> HCI Event: Command Complete (0x0e) plen 68
      Read Local OOB Extended Data (0x03|0x007d) ncmd 1
        Status: Success (0x00)
        Hash C from P-192: 6489731804b156fa6355efb8124a1389
        Randomizer R with P-192: 4781d5352fb215b2958222b3937b6026
        Hash C from P-256: 69ef8a928b9d07fc149e630e74ecb991
        Randomizer R with P-256: 4781d5352fb215b2958222b3937b6026

The change for the management interface is transparent and no change
is required for existing userspace. The Secure Connections feature
needs to be manually enabled. When it is disabled, then userspace
only gets the P-192 returned and with Secure Connections enabled,
userspace gets P-192 and P-256 in an extended structure.

It is also acceptable to just ignore the P-256 data since it is not
required to support them. The pairing with out-of-band credentials
will still succeed. However then of course no Secure Connection will
b established.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The support for Secure Connections need to be explicitly enabled by
userspace. This is required since only userspace that can handle the
new link key types should enable support for Secure Connections.

This command handling is similar to how Secure Simple Pairing enabling
is done. It also tracks the case when Secure Connections support is
enabled via raw HCI commands. This makes sure that the host features
page is updated as well.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

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: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

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: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The check for HIGH security level dates back to pre-mgmt times when a
raw L2CAP socket with HIGH security level was used to trigger dedicated
bonding. For legacy pairing checking for the security level was the only
way to catch the need to authenticate in all scenarios. With mgmt
however, the pair_device command does not use HIGH security but MEDIUM
security. Therefore, the existing code would never trigger
authentication for a non-SSP connection without an MITM requirement
(e.g. if user space provided a NoInputNoOutput IO capability). In such a
scenario the mgmt_pair_device command would return success without
actually triggering any kind of pairing.

This patch updates the authentication requirement check to also consider
MEDIUM security level, and thereby ensures that mgmt_pair_device will
always trigger authentication.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This is initial version of
http://tools.ietf.org/html/draft-ietf-6lo-btle-00

By default the 6LoWPAN support is not activated and user
needs to tweak /sys/kernel/debug/bluetooth/hci0/6lowpan
file.

The kernel needs IPv6 support before 6LoWPAN is usable.
Signed-off-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

hci_disconn_complete_evt() logic is more complicated than what it
should be, making it hard to follow and add new features.

So this patch does some code refactoring by handling the error cases
in the beginning of the function and by moving the main flow into the
first level of function scope. No change is done in the event handling
logic itself.

Besides organizing this messy code, this patch makes easier to add
code for handling LE auto connection (which will be added in a further
patch).
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

According to b644ba33 (patch that introduced HCI_CONN_MGMT_CONNECTED
flag), the HCI_CONN_MGMT_CONNECTED flag tracks when mgmt has been
notified about the connection.

That being said, there is no point in calling mgmt_disconnect_failed()
conditionally based on this flag. mgmt_disconnect_failed() removes
pending MGMT_OP_DISCONNECT commands, it doesn't matter if that
connection was notified or not.

Moreover, if the Disconnection Complete event has status then we have
nothing else to do but call mgmt_disconnect_failed() and return.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

We can safely remove the link type check from hci_disconn_complete_
evt() since this check in not required for mgmt_disconnect_failed()
and mgmt_device_disconnected() does it internally.
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The list of supported commands of a controller can not change during
its lifetime. So store the list just once during the setup procedure
and not every time the HCI command is executed.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The complete list of local features are available through debugfs and
so there is no need to add a debug print here.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Enabling and disabling SSP debug mode is useful for development. This
adds a debugfs entry that allows to configure the SSP debug mode.

On purpose this has been implemented as debugfs entry and not a public
API since it is really only useful during testing and development.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The conn->interval parameter of HCI connections is not used at all
and so just remove it.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

The local version information from the controller can not change
since they are static. So store them only once during setup
phase and not bother overwriting them every time this command
gets executed.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

Some controllers list the max_page value from the extended features
response as 0 when SSP has not yet been enabled. To workaround this
issue, force the max_page value to 1 when SSP support has been
detected.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>