This is a temporary patch where user can manually enable or
disable BT 6LoWPAN functionality between devices.
Eventually the connection is established automatically if
the devices are advertising suitable capability and this patch
can be removed.

Before connecting the devices do this

echo Y > /sys/kernel/debug/bluetooth/hci0/6lowpan

This enables 6LoWPAN support and creates the bt0 interface
automatically when devices are finally connected.

Rebooting or unloading the bluetooth kernel module will also clear the
settings from the kernel.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel 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: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Used for IPv6 over LoWPAN networks. Example of this is
Bluetooth 6LoWPAN network.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Because the IEEE 802154 and Bluetooth share the IP header compression
and uncompression code, the common code is moved to 6lowpan_iphc.c
file.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

If we receive an L2CAP command reject message over LE we should take
appropriate action on the corresponding channel. This is particularly
important when trying to interact with a remote pre-4.1 system using LE
CoC signaling messages. If we don't react to the command reject the
corresponding socket would not be notified until a connection timeout
occurs.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Add the LMP feature constants for connectionless slave broadcast
and use them for capability testing.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

With the addition of L2CAP Connection Oriented Channels for Bluetooth
Low Energy connections, it makes sense to increase the minor version
of the Bluetooth core module.

The module version is not used anywhere, but it gives a nice extra
hint for debugging purposes.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

The range of valid LE PSMs is 0x0001-0x00ff so the check should be for
"less than or equal to" instead of "less than".
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Since there's a nice convenient helper for calculating the minimum of
two values, let's use that one.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The values in l2cap_chan that are used for actually transmitting data
only need to be initialized right after we've received an L2CAP Connect
Request or just before we send one. The only thing that we need to
initialize though bind() and connect() is the chan->mode value. This way
all other initializations can be done in the l2cap_le_flowctl_init
function (which now becomes private to l2cap_core.c) and the
l2cap_le_flowctl_start function can be completely removed.

Also, since the l2cap_sock_init function initializes the imtu and omtu
to adequate values these do not need to be part of l2cap_le_flowctl_init.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds entries to debugfs to control the values used for the
MPS and Credits for LE Flow Control Mode.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

LE PSM values have different ranges than those for BR/EDR. The valid
ranges for fixed, SIG assigned values is 0x0001-0x007f and for dynamic
PSM values 0x0080-0x00ff. We need to ensure that bind() and connect()
calls conform to these ranges when operating on LE CoC sockets.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

LE CoC used differend CIC ranges than BR/EDR L2CAP. The start of the
range is the same (0x0040) but the range ends at 0x007f (unlike BR/EDR
where it goes all the way to 0xffff).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The outgoing MTU should only be set upon channel creation to the initial
minimum value (23) or from a remote connect req/rsp PDU.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

It doesn't make sense to have an MPS value greater than the configured
MTU value since we will then not be able to fill up the packets to their
full possible size. We need to set the MPS both in flowctl_init()
as well as flowctl_start() since the imtu may change after init() but
start() is only called after we've sent the LE Connection Request PDU
which depends on having a valid MPS value.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

If the peer gives us zero credits in its connection request or response
we must call the suspend channel callback so the BT_SK_SUSPEND flag gets
set and user space is blocked from sending data to the socket.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Unlike BR/EDR, for LE when we're in the BT_CONNECT state we may or may
not have already have sent the Connect Request. This means that we need
some extra tracking of the request. This patch adds an extra channel
flag to prevent the request from being sent a second time.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

When receiving fragments over an LE Connection oriented Channel they
need to be collected up and eventually merged into a single SDU. This
patch adds the necessary code for collecting up the fragment skbs to the
channel context and passing them to the recv() callback when the entire
SDU has been received.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds segmentation support for outgoing data packets. Packets
are segmented based on the MTU and MPS values. The l2cap_chan struct
already contains many helpful variables from BR/EDR Enhanced L2CAP which
can be used for this.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Setting the BT_SK_SUSPEND socket flag from the L2CAP core is causing a
dependency on the socket. So instead of doing that, use a channel
callback into the socket handling to suspend.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Since LE CoC support needs to be enabled through a module option for now
we need to reject any related signaling PDUs in addition to rejecting
the creation of LE CoC sockets (which we already do).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds the necessary discipline for reacting to LE L2CAP
Credits packets, sending those packets, and modifying the known credits
accordingly.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

We should return credits to the remote side whenever they fall below a
certain level (in our case under half of the initially given amount).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds new socket options for LE sockets since the existing
L2CAP_OPTIONS socket option is not usable for LE. For now, the new
socket options also require LE CoC support to be explicitly enabled to
leave some playroom in case something needs to be changed in a backwards
incompatible way.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Most of the values in L2CAP_OPTIONS are not applicable for LE and those
that are have different semantics. It makes therefore sense to
completely block this socket option for LE and add (in a separate patch)
a new socket option for tweaking the values that do make sense (mainly
the send and receive MTU). Legacy user space ATT code still depends on
getsockopt for L2CAP_OPTIONS though so we need to plug a hole for that
for backwards compatibility.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds tracking of L2CAP connection oriented channel local and
remote credits to struct l2cap_chan and ensures that connect requests
and responses contain the right values.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The LE connection oriented channels have their own mode with its own
data transfer rules. In order to implement this properly we need to
distinguish L2CAP channels operating in this mode from other modes.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch makes the error handling and return logic of l2cap_le_sig_cmd
consistent with its BR/EDR counterpart.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The normal L2CAP Disconnect request and response are also used for LE
connection oriented channels. Therefore, we can simply use the existing
handler functions for terminating LE based L2CAP channels.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Sending of the L2CAP Disconnect request should also be performed for LE
based channels. The proper thing to do is therefore to look at whether
there's a PSM specified for the channel instead of looking at the link
type.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds the necessary boiler plate code to handle receiving
L2CAP connect requests over LE and respond to them with a proper connect
response.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

We'll need to have a separate code path for LE based connection
rejection so it's cleaner to move out the response construction code
into its own function (and later a second one for LE).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This function is needed both by the smp_conn_security function as well
as upcoming code to check for the security requirements when receiving
an L2CAP connect request over LE.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds the necessary code to send an LE L2CAP Connect Request
and handle its response when user space has provided us with an LE
socket with a PSM instead of a fixed CID.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds the necessary defines and structs for LE connection
oriented channels.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Once connection oriented L2CAP channels over LE are supported they will
need a completely separate handling from BR/EDR channels.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The LE signaling PDU length is already calculated in the
l2cap_le_sig_channel function so we can just pass the value to the
various handler functions to avoid unnecessary recalculations (byte
order conversions). Right now the only user is the connection parameter
update procedure, but as new LE signaling operations become available
(for connection oriented channels) they will also be able to make use of
the value.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

With connection oriented L2CAP channels some code paths will be shared
with BR/EDR links. It is therefore necessary to allow the
l2cap_chan_check_security function to be usable also for LE links in
addition to BR/EDR ones. This means that smp_conn_security() needs to be
called instead of hci_conn_security() in the case of an LE link.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Once connection oriented L2CAP channels become possible for LE we need
to be able to specify the link type we're interested in when looking up
L2CAP channels. Therefore, add a link_type parameter to the
l2cap_global_chan_by_psm() function which gets compared to the address
type associated with each l2cap_chan.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>