The GAP Specification gives the flexibility to decide whether MITM
Protection is requested or not (Bluetooth Core Specification v4.0
Volume 3, part C, section 6.5.3) when replying to an
HCI_EV_IO_CAPA_REQUEST event.
The recommendation is *not* to set this flag "unless the security
policy of an available local service requires MITM Protection"
(regardless of the bonding type). However, the kernel doesn't
necessarily have this information and therefore the safest choice is
to always use MITM Protection, also for General Bonding.
This patch changes the behavior for the General Bonding initiator
role, always requesting MITM Protection even if no high security level
is used. Depending on the remote capabilities, the protection might
not be actually used, and we will accept this locally unless of course
a high security level was originally required.
Note that this was already done for Dedicated Bonding. No-Bonding is
left unmodified because MITM Protection is normally not desired in
these cases.
Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
Signed-off-by: Timo Mueller <timo.mueller@bmw-carit.de>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When responding to a remotely-initiated pairing procedure, a MITM
protected SSP associaton model can be used for pairing if both local
and remote IO capabilities are set to something other than
NoInputNoOutput, regardless of the bonding type (Dedicated or
General).
This was already done for Dedicated Bonding but this patch proposes to
use the same policy for General Bonding as well.
The GAP Specification gives the flexibility to decide whether MITM
Protection is used ot not (Bluetooth Core Specification v4.0 Volume 3,
part C, section 6.5.3).
Note however that the recommendation is *not* to set this flag "unless
the security policy of an available local service requires MITM
Protection" (for both Dedicated and General Bonding). However, as we are
already requiring MITM for Dedicated Bonding, we will follow this
behaviour also for General Bonding.
Signed-off-by: Timo Mueller <timo.mueller@bmw-carit.de>
Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Do not always set the MITM protection requirement by default in the
field conn->auth_type, since this will be added later in
hci_io_capa_request_evt(), as part of the requirements specified in
HCI_OP_IO_CAPABILITY_REPLY.
This avoids a hackish exception for the auto-reject case, but doesn't
change the behavior of the code at all.
Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Refactor the code without changing its behavior by handling the
no-bonding cases first followed by General Bonding.
Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
Signed-off-by: Timo Mueller <timo.mueller@bmw-carit.de>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When sending out a device found event caused by an advertising report in
the situation where we couldn't store the report as a pending one, the
code was incorrectly trying to use the address and address type from the
pending data. Since the pending data is cleared in the previous line
this causes a potentially incorrect address type and an address of
BDADDR_ANY. This patch fixes the call to use the address information
correctly from the received advertising report.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To be consistent, lets use msec for this timeout as well.
Note: This define value is a minimum scan time taken from BT Core spec 4.0,
Vol 3, Part C, chapter 9.2.6
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With this patch it is possible to control discovery interleaved
timeout value from debugfs.
It is for fine tuning of this timeout.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Keep msec instead of jiffies in this define. This is needed by following
patch where we want this timeout to be exposed in debugfs.
Note: Value of this timeout comes from recommendation in BT Core Spec.4.0,
Vol 3, Part C, chapter 13.2.1.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The ssp parameter is supposed to be a mandatory one and there are no
callers that would pass NULL to this function. Removing this unnecessary
NULL check also makes (false positive) static analyzer warnings go away.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When sending a pending device found event triggered by disabling LE
scanning we should use the stored RSSI instead of sending a zero value.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Especially in crowded environments it can become frequent that we have
to send out whatever pending event there is stored. Since user space
has its own filtering of small RSSI changes sending a 0 value will
essentially force user space to wake up the higher layers (e.g. over
D-Bus) even though the RSSI didn't actually change more than the
threshold value.
This patch adds storing also of the RSSI for pending advertising reports
so that we report an as accurate RSSI as possible when we have to send
out the stored information to user space.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Occasionally, during active scanning we will receive duplicate ADV_IND
reports from the same device before receiving the SCAN_RSP from them. In
order to not wake up user space unnecessarily it's better not to send
these extra events as they do not contain any new information.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The line was incorrectly split between the variable type and its name.
This patch fixes the issue.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
All callers of hci_inquiry_cache_update() pass a non-NULL ssp pointer to
it and even the function itself assumes in another place that the
pointer is non-NULL. Therefore, remove the redundant check.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To avoid too many events being sent to user space and to help parsing of
all available remote device data it makes sense for us to wait for the
scan response and send a single merged Device Found event to user space.
This patch adds a few new variables to hci_dev to track the last
received ADV_IND/ADV_SCAN_IND, i.e. those which will cause a SCAN_REQ to
be send in the case of active scanning. When the SCAN_RSP is received
the pending data is passed together with the SCAN_RSP to the
mgmt_device_found function which takes care of merging them into a
single Device Found event.
We also need a bit of extra logic to handle situations where we don't
receive a SCAN_RSP after caching some data. In such a scenario we simply
have to send out the pending data as it is and then operate on the new
report as if there was no pending data.
We also need to send out any pending data when scanning stops as
well as ensure that the storage is empty at the start of a new active
scanning session. These both cases are covered by the update to the
hci_cc_le_set_scan_enable function in this patch.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When we're in peripheral mode (HCI_ADVERTISING flag is set) the most
natural mapping of connect() is to perform directed advertising to the
peer device.
This patch does the necessary changes to enable directed advertising and
keeps the hci_conn state as BT_CONNECT in a similar way as is done for
central or BR/EDR connection initiation.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In preparation for being able to merge ADV_IND/ADV_SCAN_IND and SCAN_RSP
together into a single device found event add a second parameter to the
mgmt_device_found function. For now all callers pass NULL as this
parameters since we don't yet have storing of the last received
advertising report.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Passive LE scanning is only used by the kernel-internal connection
establishment procedure. It makes therefore little sense to send device
found events to user space.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When a timeout occurs using directed advertising a 0x3c error gets
generated. Since the operation is analogous to conventional connection
creation map this to the usual EHOSTDOWN error.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Once directed advertising is brought into the picture simply the lack of
an hci_conn object when an le_conn_complete event occurs is no longer a
reliable indication that the responder & initiator values need to be
set based on our advertising address type.
This patch moves the code for setting these values outside of the
"if (!conn)" branch and ensures that they get set for any connection
where we are in the slave role.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Any time hci_conn_add is used for an LE connection we need to ensure
that the local identity address is correctly described in the src and
src_type variables. This patch moves setting these values directly into
hci_conn_add so that callers don't have to duplicate the effort
themselves.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch does a small code simplification replacing the tipical
kmalloc-copy_from_user sequence by memdup_user() helper.
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
As preparation for merging ADV_IND/ADV_SCAN_IND and SCAN_RSP together
into a single mgmt Device Found event refactor individual advertising
report handling into a separate function. This will help keep the code
more readable as more logic gets added.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We should let user space request the peer address also in the pending
connect states, i.e. BT_CONNECT and BT_CONNECT2. There is existing user
space code that tries to do this and will fail without extending the set
of allowed states for the peer address information.
This patch adds the two states to the allowed ones in the L2CAP and
RFCOMM sock_getname functions, thereby preventing ENOTCONN from being
returned.
Reported-by: Andrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Andrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The smp variable in smp_conn_security is not used anywhere before the
smp = smp_chan_create() call in the smp_conn_security function so it
makes no sense to assign any other value to it before that.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The smp pointer might not be initialized for jumps to the "done" label
in the smp_conn_security function. Furthermore doing the set_bit after
done might "overwrite" a previous value of the flag in case pairing was
already in progress. This patch moves the call to set_bit before the
label so that it is only done for a newly created smp context (as
returned by smp_chan_create).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Due to several devices being unable to handle this procedure reliably
(resulting in forced disconnections before pairing completes) it's
better to remove it altogether.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In the case that the just-works model would be triggered we only want to
confirm remotely initiated pairings (i.e. those triggered by a Security
Request or Pairing Request). This patch adds the necessary check to the
tk_request function to fall back to the JUST_WORKS method in the case of
a locally initiated pairing.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For remotely initiated just-works pairings we want to show the user a
confirmation dialog for the pairing. However, we can only know which
side was the initiator by tracking which side sends the first Security
Request or Pairing Request PDU. This patch adds a new SMP flag to
indicate whether our side was the initiator for the pairing.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In the case that a local pairing confirmation (JUST_CFM) has been
selected as the method we need to use the user confirm request mgmt
event for it with the confirm_hint set to 1 (to indicate confirmation
without any specific passkey value). Without this (if passkey_notify was
used) the pairing would never proceed. This patch adds the necessary
call to mgmt_user_confirm_request in this scenario.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
It is possible that the HCI_LE_Start_Encryption command fails in an
early stage and triggers a command status event with the failure code.
In such a case we need to properly notify the hci_conn object and
cleanly bring the connection down. This patch adds the missing command
status handler for this HCI command.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The LE scan type paramter defines if active scanning or passive scanning
is in use. Track the currently set value so it can be used for decision
making from other pieces in the core.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
We need to ensure that we do not send events to user space with the
identity address if we have not yet notified user space of the IRK. The
code was previously trying to handle this for the mgmt_pair_device
response (which worked well enough) but this is not the only connection
related event that might be sent to user space before pairing is
successful: another important event is Device Disconnected.
The issue can actually be solved more simply than the solution
previously used for mgmt_pair_device. Since we do have the identity
address tracked as part of the remote IRK struct we can just copy it
over from there to the hci_conn struct once we've for real sent the mgmt
event for the new IRK.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The passkey_notify and user_confirm functions in mgmt.c were expecting
different endianess for the passkey, leading to a big endian bug and
sparse warning in recently added SMP code. This patch converts both
functions to expect host endianess and do the conversion to little
endian only when assigning to the mgmt event struct.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
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>
It is possible that pairing fails after we've already received remote
identity information. One example of such a situation is when
re-encryption using the LTK fails. In this case the hci_conn object has
already been updated with the identity address but user space does not
yet know about it (since we didn't notify it of the new IRK yet).
To ensure user space doesn't get a Pair Device command response with an
unknown address always use the same address in the response as was used
for the original command.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When performing SMP pairing with MITM protection one side needs to
enter the passkey while the other side displays to the user what needs
to be entered. Nowhere in the SMP specification does it say that the
displaying side needs to any kind of confirmation of the passkey, even
though a code comment in smp.c implies this.
This patch removes the misleading comment and converts the code to use
the passkey notification mgmt event instead of the passkey confirmation
mgmt event.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In some cases the current 250ms delay is not enough for the remote to
receive the keys, as can be witnessed by the following log:
> ACL Data RX: Handle 64 flags 0x02 dlen 21 [hci1] 231.414217
SMP: Signing Information (0x0a) len 16
Signature key: 555bb66b7ab3abc9d5c287c97fe6eb29
< ACL Data TX: Handle 64 flags 0x00 dlen 21 [hci1] 231.414414
SMP: Encryption Information (0x06) len 16
Long term key: 2a7cdc233c9a4b1f3ed31dd9843fea29
< ACL Data TX: Handle 64 flags 0x00 dlen 15 [hci1] 231.414466
SMP: Master Identification (0x07) len 10
EDIV: 0xeccc
Rand: 0x322e0ef50bd9308a
< ACL Data TX: Handle 64 flags 0x00 dlen 21 [hci1] 231.414505
SMP: Signing Information (0x0a) len 16
Signature key: bbda1b2076e2325aa66fbcdd5388f745
> HCI Event: Number of Completed Packets (0x13) plen 5 [hci1] 231.483130
Num handles: 1
Handle: 64
Count: 2
< HCI Command: LE Start Encryption (0x08|0x0019) plen 28 [hci1] 231.664211
Handle: 64
Random number: 0x5052ad2b75fed54b
Encrypted diversifier: 0xb7c2
Long term key: a336ede66711b49a84bde9b41426692e
> HCI Event: Command Status (0x0f) plen 4 [hci1] 231.666937
LE Start Encryption (0x08|0x0019) ncmd 1
Status: Success (0x00)
> HCI Event: Number of Completed Packets (0x13) plen 5 [hci1] 231.712646
Num handles: 1
Handle: 64
Count: 1
> HCI Event: Disconnect Complete (0x05) plen 4 [hci1] 232.562587
Status: Success (0x00)
Handle: 64
Reason: Remote User Terminated Connection (0x13)
As can be seen, the last key (Signing Information) is sent at 231.414505
but the completed packets event for it comes only at 231.712646,
i.e. roughly 298ms later.
To have a better margin of error this patch increases the delay to
500ms.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This is a trivial coding style simplification by instead of having an
extra early return to instead revert the if condition and do the single
needed queue_work() call there.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The pairing process initiated through mgmt sets the conn->auth_type
value regardless of BR/EDR or LE pairing. This value will contain the
MITM flag if the local IO capability allows it. When sending the SMP
pairing request we should check the value and ensure that the MITM bit
gets correctly set in the bonding flags.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The SMP specification is written with the assumption that both key
information, plaintextData and encryptedData follow the same little
endian byte ordering as the rest of SMP.
Since the kernel crypto routines expect big endian data the code has had
to do various byte swapping tricks to make the behavior as expected,
however the swapping has been scattered all around the place.
This patch centralizes the byte order swapping into the smp_e function
by making its public interface match what the other SMP functions expect
as per specification. The benefit is vastly simplified calls to smp_e.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To make it possible to (correctly) pass data declared as const as the
src parameter to the swap56 and swap128 functions declare this parameter
also as const.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When performing pairing using SMP the remote may clear any key
distribution bits it wants in its pairing response. We must therefore
update our local variable accordingly, otherwise we might get stuck
waiting for keys that will never come.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Commit 975508879 "Bluetooth: make bluetooth 6lowpan as an option"
ensures that 6LOWPAN_IPHC is turned on when we have BT_6LOWPAN
enabled in Kconfig, but it allows building the IPHC code as
a loadable module even if the entire Bluetooth stack is built-in,
and that causes a link error.
We can solve that by moving the 'select' statement into CONFIG_BT,
which is a "tristate" option to enforce that 6LOWPAN_IPHC can
only be a module if BT also is a module.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
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>
To avoid flooding the host with useless advertising reports during
background scan, we enable the duplicates filter from controller.
However, enabling duplicates filter requires a small change in
background scan routine in order to fix the following scenario:
1) Background scan is running.
2) A device disconnects and starts advertising.
3) Before host gets the disconnect event, the advertising is reported
to host. Since there is no pending LE connection at that time,
nothing happens.
4) Host gets the disconnection event and adds a pending connection.
5) No advertising is reported (since controller is filtering) and the
connection is never established.
So, to address this scenario, we should always restart background scan
to unsure we don't miss any advertising report (due to duplicates
filter).
Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Currently you can have bluetooth 6lowpan without ipv6 enabled. This
doesn't make any sense. With this patch you can disable/enable bluetooth
6lowpan support at compile time.
The current bluetooth 6lowpan implementation doesn't check the return
value of 6lowpan function. Nevertheless I added -EOPNOTSUPP as return value
if 6lowpan bluetooth is disabled.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In case the pairable option has been disabled, the pairing procedure
does not create keys for bonding. This means that these generated keys
should not be stored persistently.
For LTK and CSRK this is important to tell userspace to not store these
new keys. They will be available for the lifetime of the device, but
after the next power cycle they should not be used anymore.
Inform userspace to actually store the keys persistently only if both
sides request bonding.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
