When disconnecting it is possible that the l2cap_conn pointer is already
NULL when bt_6lowpan_del_conn() is entered. Looking at l2cap_conn_del
also verifies this as there's a NULL check there too. This patch adds
the missing NULL check without which the following bug may occur:

BUG: unable to handle kernel NULL pointer dereference at   (null)
IP: [<c131e9c7>] bt_6lowpan_del_conn+0x19/0x12a
*pde = 00000000
Oops: 0000 [#1] SMP
CPU: 1 PID: 52 Comm: kworker/u5:1 Not tainted 3.12.0+ #196
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: hci0 hci_rx_work
task: f6259b00 ti: f48c0000 task.ti: f48c0000
EIP: 0060:[<c131e9c7>] EFLAGS: 00010282 CPU: 1
EIP is at bt_6lowpan_del_conn+0x19/0x12a
EAX: 00000000 EBX: ef094e10 ECX: 00000000 EDX: 00000016
ESI: 00000000 EDI: f48c1e60 EBP: f48c1e50 ESP: f48c1e34
 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
CR0: 8005003b CR2: 00000000 CR3: 30c65000 CR4: 00000690
Stack:
 f4d38000 00000000 f4d38000 00000002 ef094e10 00000016 f48c1e60 f48c1e70
 c1316bed f48c1e84 c1316bed 00000000 00000001 ef094e10 f48c1e84 f48c1ed0
 c1303cc6 c1303c7b f31f331a c1303cc6 f6e7d1c0 f3f8ea16 f3f8f380 f4d38008
Call Trace:
 [<c1316bed>] l2cap_disconn_cfm+0x3f/0x5b
 [<c1316bed>] ? l2cap_disconn_cfm+0x3f/0x5b
 [<c1303cc6>] hci_event_packet+0x645/0x2117
 [<c1303c7b>] ? hci_event_packet+0x5fa/0x2117
 [<c1303cc6>] ? hci_event_packet+0x645/0x2117
 [<c12681bd>] ? __kfree_skb+0x65/0x68
 [<c12681eb>] ? kfree_skb+0x2b/0x2e
 [<c130d3fb>] ? hci_send_to_sock+0x18d/0x199
 [<c12fa327>] hci_rx_work+0xf9/0x295
 [<c12fa327>] ? hci_rx_work+0xf9/0x295
 [<c1036d25>] process_one_work+0x128/0x1df
 [<c1346a39>] ? _raw_spin_unlock_irq+0x8/0x12
 [<c1036d25>] ? process_one_work+0x128/0x1df
 [<c103713a>] worker_thread+0x127/0x1c4
 [<c1037013>] ? rescuer_thread+0x216/0x216
 [<c103aec6>] kthread+0x88/0x8d
 [<c1040000>] ? task_rq_lock+0x37/0x6e
 [<c13474b7>] ret_from_kernel_thread+0x1b/0x28
 [<c103ae3e>] ? __kthread_parkme+0x50/0x50
Code: 05 b8 f4 ff ff ff 8d 65 f4 5b 5e 5f 5d 8d 67 f8 5f c3 57 8d 7c 24 08 83 e4 f8 ff 77 fc 55 89 e5 57 56f
EIP: [<c131e9c7>] bt_6lowpan_del_conn+0x19/0x12a SS:ESP 0068:f48c1e34
CR2: 0000000000000000
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

There exists a set of Bluetooth USB devices that show up on the USB
bus as 0a12:0001 and identify themselves as devices from CSR. However
they are not. When sending Read Local Version command they now have
a split personality and say they are from Broadcom.

  < HCI Command: Read Local Version Information (0x04|0x0001) plen 0
  > HCI Event: Command Complete (0x0e) plen 12
      Read Local Version Information (0x04|0x0001) ncmd 1
      status 0x00
      HCI Version: 2.0 (0x3) HCI Revision: 0x3000
      LMP Version: 2.0 (0x3) LMP Subversion: 0x420b
      Manufacturer: Broadcom Corporation (15)

The assumption is that they are neither CSR nor Broadcom based devices
and that they are designed and manufactured by someone else.

For the most parts they follow the Bluetooth HCI specification and
can be used as standard Bluetooth devices. However they have the
minor problem that the Delete Stored Link Key command is not working
as it should.

During the Bluetooth controller setup, this command is needed if
stored link keys are supported. For these devices it has to be
assumed that this is broken and so just set a quirk to clearly
indicate the behavior. After that the setup can just proceed.

Now the trick part is to detect these faulty devices since we do
not want to punish all CSR and all Broadcom devices. The original
devices do actually work according to the specification.

What is known so far is that these broken devices set the USB bcdDevice
revision information to 1.0 or less.

T:  Bus=02 Lev=01 Prnt=01 Port=08 Cnt=03 Dev#=  9 Spd=12   MxCh= 0
D:  Ver= 2.00 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=0a12 ProdID=0001 Rev= 1.00
S:  Manufacturer=Bluetooth v2.0
S:  Product=Bluetooth V2.0 Dongle

T:  Bus=05 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  2 Spd=12   MxCh= 0
D:  Ver= 1.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=0a12 ProdID=0001 Rev= 0.07

In case of CSR devices, the bcdDevice revision contains the firmware
build ID and that is normally a higher value. If the bcdDevice revision
is 1.0 or less, then an extra setup stage is checking if Read Local
Version returns CSR manufacturer information. If not then it will be
assumed that this is a broken device and the Delete Stored Link Key
command will be marked as broken.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

Some controller pretend they support the Delete Stored Link Key command,
but in reality they really don't support it.

  < HCI Command: Delete Stored Link Key (0x03|0x0012) plen 7
      bdaddr 00:00:00:00:00:00 all 1
  > HCI Event: Command Complete (0x0e) plen 4
      Delete Stored Link Key (0x03|0x0012) ncmd 1
      status 0x11 deleted 0
      Error: Unsupported Feature or Parameter Value

Not correctly supporting this command causes the controller setup to
fail and will make a device not work. However sending the command for
controller that handle stored link keys is important. This quirk
allows a driver to disable the command if it knows that this command
handling is broken.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

The register for setting the SDIO card mode of a Type-B Bluetooth card
is called MD SET. The MD STAT register is used for reading the current
mode back.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

The Bluetooth virtual HCI driver is using a misc character device to
allow emulation of HCI devices from userspace. This change enables the
support for vectored writes. Previously this was failing with EINVAL
since no complete H:4 packet was written.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

The Socket Bluetooth SDIO cards are branded versions of Toshiba SD-BT2
and they do not support sending HCI_Reset as first command. To make
this card work the HCI_QUIRK_RESET_ON_CLOSE quirk needs to be set
before registering the controller.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

This patch remove unnecessary casts and brackets in compress_udp_header
function.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Cleanup code to handle both calculation in the same way.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Cleanup the lowpan_uncompress_udp_header function to use the
lowpan_fetch_skb function.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Bit 5 of "UDP LOWPAN_NHC Format" indicate that the checksum can be
elided.
The host need to calculate the udp checksum afterwards but this isn't
supported right now.

See:
http://tools.ietf.org/html/rfc6282#section-4.3.3Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The incoming udp header in lowpan_compress_udp_header function is
already in network byte order.

Everytime we read this values for source and destination port we need
to convert this value to host byte order.

In the outcoming header we need to set this value in network byte order
which the upcoming process assumes.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

In case ((ntohs(uh->source) & LOWPAN_NHC_UDP_8BIT_MASK) the order of
uncompression is wrong. It's always first source port then destination
port as second.

See:
http://tools.ietf.org/html/rfc6282#section-4.3.3

"Fields carried in-line (in part or in whole) appear in the same order
as they do in the UDP header format"
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch uses the lowpan_push_hc_data to generate iphc header.

The current implementation has some wrong pointer arithmetic issues and
works in a random case only.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch introduce the lowpan_push_hc_data function to set data in
the iphc buffer.

It's a common case to set data and increase the buffer pointer. This
helper function can be used many times in header_compress function to
generate the iphc header.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

In case of error, the function bt_skb_alloc() returns NULL pointer
not ERR_PTR(). The IS_ERR() test in the return value check should
be replaced with NULL test.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Remove including <linux/version.h> that don't need it.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

There are several issues on current debug behaviour.
This patch fix the following issues:

- Fix debug printout only if DEBUG is defined.
- Move debug functions of 6LoWPAN code into 6lowpan header.
- Cleanup codestyle of debug functions.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The condition wouldn't have previously caused -ENOENT to be returned if
dev was NULL. The proper condition should be if (!dev || !dev->netdev).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The 6lowpan.c file was missing an #include statement for 6lowpan.h.
Without it we get the following type of warnings:

net/bluetooth/6lowpan.c:320:5: warning: symbol 'bt_6lowpan_recv' was not declared. Should it be static?
net/bluetooth/6lowpan.c:737:5: warning: symbol 'bt_6lowpan_add_conn' was not declared. Should it be static?
net/bluetooth/6lowpan.c:805:5: warning: symbol 'bt_6lowpan_del_conn' was not declared. Should it be static?
net/bluetooth/6lowpan.c:878:5: warning: symbol 'bt_6lowpan_init' was not declared. Should it be static?
net/bluetooth/6lowpan.c:883:6: warning: symbol 'bt_6lowpan_cleanup' was not declared. Should it be static?
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

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>