When authentication fails for a connection the assumed security level
should be set back to BT_SECURITY_LOW so that subsequent connect
attempts over the same link don't falsely assume that security is
adequate enough.
Signed-off-by: Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The tasklet schedule function helpers are just an obfuscation. So remove
them and call the schedule functions directly.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The device model itself has no real usable reference counting at the
moment and this causes problems if parents are deleted before their
children. The device model itself handles the memory details of this
correctly, but the uevent order is not consistent. This causes various
problems for systems like HAL or even X.
So until device_put() does a proper cleanup, the device for Bluetooth
connection will be protected with an extra reference counting to ensure
the correct order of uevents when connections are terminated.
This is not an automatic feature. Higher Bluetooth layers like HIDP or
BNEP should grab this new reference to ensure that their uevents are
send before the ones from the parent device.
Based on a report by Brian Rogers <brian@xyzw.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
A remote device in security mode 3 that tries to connect will require
the pairing during the connection setup phase. The disconnect timeout
is now triggered within 10 milliseconds and causes the pairing to fail.
If a connection is not fully established and a PIN code request is
received, don't trigger the disconnect timeout. The either successful
or failing connection complete event will make sure that the timeout
is triggered at the right time.
The biggest problem with security mode 3 is that many Bluetooth 2.0
device and before use a temporary security mode 3 for dedicated
bonding.
Based on a report by Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Johan Hedberg <johan.hedberg@nokia.com>
The Bluetooth stack uses a reference counting for all established ACL
links and if no user (L2CAP connection) is present, the link will be
terminated to save power. The problem part is the dedicated pairing
when using Legacy Pairing (Bluetooth 2.0 and before). At that point
no user is present and pairing attempts will be disconnected within
10 seconds or less. In previous kernel version this was not a problem
since the disconnect timeout wasn't triggered on incoming connections
for the first time. However this caused issues with broken host stacks
that kept the connections around after dedicated pairing. When the
support for Simple Pairing got added, the link establishment procedure
needed to be changed and now causes issues when using Legacy Pairing
When using Simple Pairing it is possible to do a proper reference
counting of ACL link users. With Legacy Pairing this is not possible
since the specification is unclear in some areas and too many broken
Bluetooth devices have already been deployed. So instead of trying to
deal with all the broken devices, a special pairing timeout will be
introduced that increases the timeout to 60 seconds when pairing is
triggered.
If a broken devices now puts the stack into an unforeseen state, the
worst that happens is the disconnect timeout triggers after 120 seconds
instead of 4 seconds. This allows successful pairings with legacy and
broken devices now.
Based on a report by Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Broadcom chips with 2.1 firmware handle the fallback case to a SCO
link wrongly when setting up eSCO connections.
< HCI Command: Setup Synchronous Connection (0x01|0x0028) plen 17
handle 11 voice setting 0x0060
> HCI Event: Command Status (0x0f) plen 4
Setup Synchronous Connection (0x01|0x0028) status 0x00 ncmd 1
> HCI Event: Connect Complete (0x03) plen 11
status 0x00 handle 1 bdaddr 00:1E:3A:xx:xx:xx type SCO encrypt 0x01
The Link Manager negotiates the fallback to SCO, but then sends out
a Connect Complete event. This is wrong and the Link Manager should
actually send a Synchronous Connection Complete event if the Setup
Synchronous Connection has been used. Only the remote side is allowed
to use Connect Complete to indicate the missing support for eSCO in
the host stack.
This patch adds a workaround for this which clearly should not be
needed, but reality is that broken Broadcom devices are deployed.
Based on a report by Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Marcel Holtman <marcel@holtmann.org>
Some Bluetooth chips (like the ones from Texas Instruments) don't do
proper eSCO negotiations inside the Link Manager. They just return an
error code and in case of the Kyocera ED-8800 headset it is just a
random error.
< HCI Command: Setup Synchronous Connection 0x01|0x0028) plen 17
handle 1 voice setting 0x0060
> HCI Event: Command Status (0x0f) plen 4
Setup Synchronous Connection (0x01|0x0028) status 0x00 ncmd 1
> HCI Event: Synchronous Connect Complete (0x2c) plen 17
status 0x1f handle 257 bdaddr 00:14:0A:xx:xx:xx type eSCO
Error: Unspecified Error
In these cases it is up to the host stack to fallback to a SCO setup
and so retry with SCO parameters.
Based on a report by Nick Pelly <npelly@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Some of the qualification tests demand that in case of failures in L2CAP
the HCI disconnect should indicate a reason why L2CAP fails. This is a
bluntly layer violation since multiple L2CAP connections could be using
the same ACL and thus forcing a disconnect reason is not a good idea.
To comply with the Bluetooth test specification, the disconnect reason
is now stored in the L2CAP connection structure and every time a new
L2CAP channel is added it will set back to its default. So only in the
case where the L2CAP channel with the disconnect reason is really the
last one, it will propagated to the HCI layer.
The HCI layer has been extended with a disconnect indication that allows
it to ask upper layers for a disconnect reason. The upper layer must not
support this callback and in that case it will nicely default to the
existing behavior. If an upper layer like L2CAP can provide a disconnect
reason that one will be used to disconnect the ACL or SCO link.
No modification to the ACL disconnect timeout have been made. So in case
of Linux to Linux connection the initiator will disconnect the ACL link
before the acceptor side can signal the specific disconnect reason. That
is perfectly fine since Linux doesn't make use of this value anyway. The
L2CAP layer has a perfect valid error code for rejecting connection due
to a security violation. It is unclear why the Bluetooth specification
insists on having specific HCI disconnect reason.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When attempting to setup eSCO connections it can happen that some link
manager implementations fail to properly negotiate the eSCO parameters
and thus fail the eSCO setup. Normally the link manager is responsible
for the negotiation of the parameters and actually fallback to SCO if
no agreement can be reached. In cases where the link manager is just too
stupid, then at least try to establish a SCO link if eSCO fails.
For the Bluetooth devices with EDR support this includes handling packet
types of EDR basebands. This is particular tricky since for the EDR the
logic of enabling/disabling one specific packet type is turned around.
This fix contains an extra bitmask to disable eSCO EDR packet when
trying to fallback to a SCO connection.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The current security model is based around the flags AUTH, ENCRYPT and
SECURE. Starting with support for the Bluetooth 2.1 specification this is
no longer sufficient. The different security levels are now defined as
SDP, LOW, MEDIUM and SECURE.
Previously it was possible to set each security independently, but this
actually doesn't make a lot of sense. For Bluetooth the encryption depends
on a previous successful authentication. Also you can only update your
existing link key if you successfully created at least one before. And of
course the update of link keys without having proper encryption in place
is a security issue.
The new security levels from the Bluetooth 2.1 specification are now
used internally. All old settings are mapped to the new values and this
way it ensures that old applications still work. The only limitation
is that it is no longer possible to set authentication without also
enabling encryption. No application should have done this anyway since
this is actually a security issue. Without encryption the integrity of
the authentication can't be guaranteed.
As default for a new L2CAP or RFCOMM connection, the LOW security level
is used. The only exception here are the service discovery sessions on
PSM 1 where SDP level is used. To have similar security strength as with
a Bluetooth 2.0 and before combination key, the MEDIUM level should be
used. This is according to the Bluetooth specification. The MEDIUM level
will not require any kind of man-in-the-middle (MITM) protection. Only
the HIGH security level will require this.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When the remote device supports only SCO connections, on receipt of
the HCI_EV_CONN_COMPLETE event packet, the connect state is changed to
BT_CONNECTED, but the socket state is not updated. Hence, the connect()
call times out even though the SCO connection has been successfully
established.
Based on a report by Jaikumar Ganesh <jaikumar@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With the introduction of CONFIG_DYNAMIC_PRINTK_DEBUG it is possible to
allow debugging without having to recompile the kernel. This patch turns
all BT_DBG() calls into pr_debug() to support dynamic debug messages.
As a side effect all CONFIG_BT_*_DEBUG statements are now removed and
some broken debug entries have been fixed.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The ACL config stage keeps holding a reference count on incoming
connections when requesting the extended features. This results in
keeping an ACL link up without any users. The problem here is that
the Bluetooth specification doesn't define an ownership of the ACL
link and thus it can happen that the implementation on the initiator
side doesn't care about disconnecting unused links. In this case the
acceptor needs to take care of this.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When attaching Bluetooth low-level connections to the bus, the bus name
is constructed from the remote address since at that time the connection
handle is not assigned yet. This has worked so far, but also caused a
lot of troubles. It is better to postpone the creation of the sysfs
entry to the time when the connection actually has been established
and then use its connection handle as unique identifier.
This also fixes the case where two different adapters try to connect
to the same remote device.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With Bluetooth 2.1 and Simple Pairing the requirement is that any new
connection needs to be authenticated and that encryption has been
switched on before allowing L2CAP to use it. So make sure that all
the requirements are fulfilled and otherwise drop the connection with
a minimal disconnect timeout of 10 milliseconds.
This change only affects Bluetooth 2.1 devices and Simple Pairing
needs to be enabled locally and in the remote host stack. The previous
changes made sure that these information are discovered before any
kind of authentication and encryption is triggered.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth technology introduces new features on a regular basis
and for some of them it is important that the hardware on both sides
support them. For features like Simple Pairing it is important that
the host stacks on both sides have switched this feature on. To make
valid decisions, a config stage during ACL link establishment has been
introduced that retrieves remote features and if needed also the remote
extended features (known as remote host features) before signalling
this link as connected.
This change introduces full reference counting of incoming and outgoing
ACL links and the Bluetooth core will disconnect both if no owner of it
is present. To better handle interoperability during the pairing phase
the disconnect timeout for incoming connections has been increased to
10 seconds. This is five times more than for outgoing connections.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Simple Pairing process can only be used if both sides have the
support enabled in the host stack. The current Bluetooth specification
has three ways to detect this support.
If an Extended Inquiry Result has been sent during inquiry then it
is safe to assume that Simple Pairing is enabled. It is not allowed
to enable Extended Inquiry without Simple Pairing. During the remote
name request phase a notification with the remote host supported
features will be sent to indicate Simple Pairing support. Also the
second page of the remote extended features can indicate support for
Simple Pairing.
For all three cases the value of remote Simple Pairing mode is stored
in the inquiry cache for later use.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Simple Pairing feature is optional and needs to be enabled by the
host stack first. The Linux kernel relies on the Bluetooth daemon to
either enable or disable it, but at any time it needs to know the
current state of the Simple Pairing mode. So track any changes made
by external entities and store the current mode in the HCI device
structure.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
During the Simple Pairing process the HCI disconnect timer must be
disabled. The way to do this is by holding a reference count of the
HCI connection. The Simple Pairing process on both sides starts with
an IO Capabilities Request and ends with Simple Pairing Complete.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The class of device value can only be retrieved via inquiry or during
an incoming connection request. Outgoing connections can't ask for the
class of device. To compensate for this the value is stored and copied
via the inquiry cache, but currently only updated via inquiry. This
update should also happen during an incoming connection request.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Some minor cosmetic cleanups to the HCI event handling to make the
code easier to read and understand.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth specification supports the default link policy settings
on a per host controller basis. For every new connection the link
manager would then use these settings. It is better to use this instead
of bothering the controller on every connection setup to overwrite the
default settings.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The connection packet type can be changed after the connection has been
established and thus needs to be properly tracked to ensure that the
host stack has always correct and valid information about it.
On incoming connections the Bluetooth core switches the supported packet
types to the configured list for this controller. However the usefulness
of this feature has been questioned a lot. The general consent is that
every Bluetooth host stack should enable as many packet types as the
hardware actually supports and leave the decision to the link manager
software running on the Bluetooth chip.
When running on Bluetooth 2.0 or later hardware, don't change the packet
type for incoming connections anymore. This hardware likely supports
Enhanced Data Rate and thus leave it completely up to the link manager
to pick the best packet type.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When trying to establish an eSCO link between two devices then it can
happen that the remote device falls back to a SCO link. Currently this
case is not handled correctly and the message dispatching will break
since it is looking for eSCO packets. So in case the configured link
falls back to SCO overwrite the link type with the correct value.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The authentication status is not communicated to both parties. This is
actually a flaw in the Bluetooth specification. Only the requesting side
really knows if the authentication was successful or not. This piece of
information is however needed on the other side to know if it has to
trigger the authentication procedure or not. Worst case is that both
sides will request authentication at different times, but this should
be avoided since it costs extra time when setting up a new connection.
For Bluetooth encryption it is required to authenticate the link first
and the encryption status is communicated to both sides. So when a link
is switched to encryption it is possible to update the authentication
status since it implies an authenticated link.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the Bluetooth 1.2 specification the Extended SCO feature for
better audio connections was introduced. So far the Bluetooth core
wasn't able to handle any eSCO connections correctly. This patch
adds simple eSCO support while keeping backward compatibility with
older devices.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth HCI commands are divided into logical OGF groups for
easier identification of their purposes. While this still makes sense
for the written specification, its makes the code only more complex
and harder to read. So instead of using separate OGF and OCF values
to identify the commands, use a common 16-bit opcode that combines
both values. As a side effect this also reduces the complexity of
OGF and OCF calculations during command header parsing.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To better support and handle eSCO links in the future a bunch of
constants needs to be added and some basic routines need to be
updated. This is the initial step.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After an inquiry completed or got canceled the Bluetooth core should
check for any pending connect attempts.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Most Bluetooth chips don't support concurrent connect requests, because
this would involve a multiple baseband page with only one radio. In the
case an upper layer like L2CAP requests a concurrent connect these chips
return the error "Command Disallowed" for the second request. If this
happens it the responsibility of the Bluetooth core to queue the request
and try again after the previous connect attempt has been completed.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In the case of device pairing the only safe method is to establish
a low-level ACL link. In this case, the remote side should not use
the disconnect timer to give the other side the chance to enter the
PIN code. If the disconnect timer is used, the connection will be
dropped to soon, because it is impossible to identify an actual user
of this link.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case of non-blocking connects it is possible that the last user
of an ACL link quits before the connection has been fully established.
This will lead to a race condition where the internal state of a
connection is closed, but the actual link has been established and is
active. In case of Bluetooth 1.2 and later devices it is possible to
call create connection cancel to abort the connect. For older devices
the disconnect timer will be used to trigger the needed disconnect.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The local version information are needed to identify certain feature
sets of devices. They must be read on device init and stored for later
use. It is also possible to access them through the device model.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The command complete event of the exit periodic inquiry command must
clear the HCI_INQUIRY flag and finish the HCI request.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch introduces the automatic sniff mode feature. This allows
the host to switch idle connections into sniff mode to safe power.
Signed-off-by: Ulisses Furquim <ulissesf@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch introduces a quirk that allows the drivers to tell the host
to correct the SCO buffer size values.
Signed-off-by: Olivier Galibert <galibert@pobox.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds the endian annotations to the Bluetooth core.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the handling of the extended inquiry responses and
inserts them into the inquiry cache.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch moves the usage of packet type into the SKB control
buffer. After this patch it is now possible to shrink the sk_buff
structure and redefine its pkt_type.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The HCI page scan repetition mode change event contains the actual
page scan repetition mode for the remote device. It is the same
value that is received from an inquiry response and it can be used
to make further reconnections faster.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements a workaround for buggy Bluetooth 1.2 devices from
Silicon Wave. Their inquiry results with RSSI contain the page scan mode
field. This field was removed in the final Bluetooth 1.2 specification.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johan Hedberg