The L2CAP core expects channel implementations to manage the reference
returned by the new_connection callback. With sockets this is already
handled with each channel being tied to the corresponding socket. With
SMP however there's no context to tie the pointer to in the
smp_new_conn_cb function. The function can also not just drop the
reference since it's the only one at that point.
For fixed channels (like SMP) the code path inside the L2CAP core from
new_connection() to ready() is short and straight-forwards. The
crucial difference is that in ready() the implementation has access to
the l2cap_conn that SMP needs associate its l2cap_chan. Instead of
taking a new reference in smp_ready_cb() we can simply assume to
already own the reference created in smp_new_conn_cb(), i.e. there is
no need to call l2cap_chan_hold().
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.19+
There's no need to clear the HCI_CONN_ENCRYPT_PEND flag in
smp_failure. In fact, this may cause the encryption tracking to get
out of sync as this has nothing to do with HCI activity.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There are LE devices on the market that start off by announcing their
public address and then once paired switch to using private address.
To be interoperable with such devices we should simply trust the fact
that we're receiving an IRK from them to indicate that they may use
private addresses in the future. Instead, simply tie the persistency
to the bonding/no-bonding information the same way as for LTKs and
CSRKs.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Conflicts:
net/ipv4/arp.c
The net/ipv4/arp.c conflict was one commit adding a new
local variable while another commit was deleting one.
Signed-off-by: David S. Miller <davem@davemloft.net>
There are several actions that smp_conn_security() might make that do
not require a valid SMP context (conn->smp pointer). One of these
actions is to encrypt the link with an existing LTK. If the SMP
context wasn't initialized properly we should still allow the
independent actions to be done, i.e. the check for the context should
only be done at the last possible moment.
Reported-by: Chuck Ebbert <cebbert.lkml@gmail.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.0+
The l2cap_conn->smp pointer may be NULL for various valid reasons where SMP has
failed to initialize properly. One such scenario is when crypto support is
missing, another when the adapter has been powered on through a legacy method.
The smp_conn_security() function should have the appropriate check for this
situation to avoid NULL pointer dereferences.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.0+
When pairing over SMP over BR/EDR the generated LTK has by default the
same key size as the BR/EDR Link Key. Make sure we don't set our
Pairing Request/Response max value to anything higher than that.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds a debugfs control to set a different minimum LE
encryption key size. This is useful for testing that implementation of
the encryption key size handling is behaving correctly (e.g. that we
get appropriate 'Encryption Key Size' error responses when necessary).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds a debugfs control to set a different maximum LE
encryption key size. This is useful for testing that implementation of
the encryption key size handling is behaving correctly.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When we notify user space of a new LTK or distribute an LTK to the
remote peer the value passed should be the shortened version so that
it's easy to compare values in various traces. The core spec also sets
the requirements for the shortening/masking as:
"The masking shall be done after generation and before being
distributed, used or stored."
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The encryption key size for LTKs is supposed to be applied only at the
moment of encryption. When generating a Link Key (using LE SC) from
the LTK the full non-shortened value should be used. This patch
modifies the code to always keep the full value around and only apply
the key size when passing the value to HCI.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To help debug legacy SMP crypto functions add debug logs of the
various values involved.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When SMP selftest is enabled, then besides printing the result into the
kernel message buffer, also create a debugfs file that allows retrieving
the same information.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
We're getting very close to the maximum possible size of bt_skb_cb. To
prepare to shrink the struct with the help of a union this patch moves
all L2CAP related variables into the l2cap_ctrl struct. To later add
other 'ctrl' structs the L2CAP one is renamed simple 'l2cap' instead
of 'control'.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When the allocation of the L2CAP channel for the BR/EDR security manager
fails, then the smp variable might be NULL. In that case do not try to
free the non-existing crypto contexts
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
OS X version 10.10.2 (and possibly older versions) doesn't support LE
Secure Connections but incorrectly copies all authentication request
bits from a Security Request to its Pairing Request. The result is that
an SC capable initiator (such as BlueZ) will think OS X intends to do SC
when in fact it's incapable of it:
< ACL Data TX: Handle 3585 flags 0x00 dlen 6
SMP: Security Request (0x0b) len 1
Authentication requirement: Bonding, No MITM, SC, No Keypresses (0x09)
> ACL Data RX: Handle 3585 flags 0x02 dlen 11
SMP: Pairing Request (0x01) len 6
IO capability: KeyboardDisplay (0x04)
OOB data: Authentication data not present (0x00)
Authentication requirement: Bonding, No MITM, SC, No Keypresses (0x09)
Max encryption key size: 16
Initiator key distribution: EncKey (0x01)
Responder key distribution: EncKey IdKey Sign (0x07)
< ACL Data TX: Handle 3585 flags 0x00 dlen 11
SMP: Pairing Response (0x02) len 6
IO capability: NoInputNoOutput (0x03)
OOB data: Authentication data not present (0x00)
Authentication requirement: Bonding, No MITM, SC, No Keypresses (0x09)
Max encryption key size: 16
Initiator key distribution: EncKey (0x01)
Responder key distribution: EncKey Sign (0x05)
The pairing eventually fails when we get an unexpected Pairing Confirm
PDU instead of a Public Key PDU:
> ACL Data RX: Handle 3585 flags 0x02 dlen 21
SMP: Pairing Confirm (0x03) len 16
Confim value: bcc3bed31b8f313a78ec3cce32685faf
It is only at this point that we can speculate that the remote doesn't
really support SC. This patch creates a workaround for the just-works
model, however the MITM case is unsolvable because the OS X user has
already been requested to enter a PIN which we're now expected to
randomly generate and show the user (i.e. a chicken-and-egg problem).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The variable for the out-of-band random number was badly named and
with that confusing. Just rename it to local_rand so it is clear
what value it represents.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Just for pure debugging purposes print the remote out-of-band data
that has been received and is going to be used.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
It might be a bit counterintuitive to set a 'local' flag based on remote
data. This patch adds a clarifying comment to the pairing req/rsp
handlers when setting the LOCAL_OOB flag based on the PDU received from
the remote side.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When we receive the remote public key, if we have remote OOB data
there's no point in sending our public key to the remote if the OOB data
doesn't match. This patch moves the test for this higher up in the
smp_cmd_public_key() function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If we haven't received remote OOB data we cannot perform any special
checks on the confirm value. This patch updates the check after having
received the public key to only perform the verification if we have
remote OOB data present.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the SMP Pairing Request or Response PDU received from the remote
device indicates that it has received our OOB data we should set the
SMP_FLAG_LOCAL_OOB flag.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There are several decisions in the SMP logic that depend not only on
whether we're doing SMP or not, but also whether local and/or remote OOB
data is present. This patch splits the existing SMP_FLAG_OOB into two
new flags to track local and remote OOB data respectively.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We need to store the local ra/rb value in order to verify the Check
value received from the remote. This patch adds a new 'lr' for the local
ra/rb value and makes sure it gets used when verifying the DHKey Check
PDU received from the remote.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The OOB public and secret key pair is different from the non-OOB pairing
procedure. SO when OOB method is in use, then use this key pair instead
of generating a new one.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
This patch adds a smp_generate_oob function that allows to create
local out-of-band data that can be used for pairing and also provides
the confirmation and random value.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The security manager device will require the use of AES-CMAC hash for
out-of-band data generation. This patch makes sure it is correctly
set up and available.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Every Bluetooth Low Energy controller requires a local crypto context
to handle the resolvable private addresses. At the moment this is just
a single crypto context, but for out-of-band data generation it will
require an additional. To facility this, create a struct smp_dev that
will hold all the extra information. This patch is just the refactoring
in preparation for future changes.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Within the security manager, it makes sense to use kzfree instead of
kfree for all data structures. This ensures that no key material leaks
by accident.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
With the extension of hdev->dev_flags utilizing a bitmap now, the space
is no longer restricted. Merge the hdev->dbg_flags into hdev->dev_flags
to save space on 64-bit architectures. On 32-bit architectures no size
reduction happens.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Instead of manually coding test_bit on hdev->dev_flags all the time,
use hci_dev_test_flag helper macro.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The SMP code contains two else branches that are not needed since the
successful test will actually leave the function.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The 'master' parameter of the New CSRK event was recently renamed to
'type', with the old values kept for backwards compatibility as
unauthenticated local/remote keys. This patch updates the code to take
into account the two new (authenticated) values and ensures they get
used based on the security level of the connection that the respective
keys get distributed over.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The only reason the SMP code is essentially duplicating the
hci_copy_identity_addr() function is that the helper returns the address
type in the HCI format rather than the three-value format expected by
l2cap_chan. This patch converts the SMP code to use the helper and then
do a simple conversion from one address type to another.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Before setting the OOB data present flag with SMP pairing, check the
newly introduced present tracking that actual OOB data values have
been provided. The existence of remote OOB data structure does not
actually mean that the correct data values are available.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When the SMP channels have been already registered, then print out a
clear WARN_ON message that something went wrong. Also unregister the
existing channels in this case before trying to register new ones.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When LE features are not supported, then do not bother registering any
kind of SMP channel.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The source address and source address type of the LE SMP channel can
either be the public address of the controller or the static random
address configured by the host.
Right now the public address is used for the LE SMP channel and
obviously that is not correct if the controller operates with the
configured static random address.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
According to the Bluetooth core specification valid identity addresses
are either Public Device Addresses or Static Random Addresses. IRKs
received with any other type of address should be discarded since we
cannot assume to know the permanent identity of the peer device.
This patch fixes a missing check for the Identity Address when receiving
the Identity Address Information SMP PDU.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.17+
The duration variable for the selftests is unsigned long long and with
that use %llu instead of %lld when printing the results.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
One of the LE Secure Connections security credentials was still using
the BT_DBG instead of SMP_DBG.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Testing cross-transport pairing that starts on BR/EDR is only valid when
using a controller with BR/EDR Secure Connections. Devices will indicate
this by providing BR/EDR SMP fixed channel over L2CAP. To allow testing
of this feature on Bluetooth 4.0 controller or controllers without the
BR/EDR Secure Connections features, introduce a force_bredr_smp debugfs
option that allows faking the required AES connection.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
After successful completion of the SMP test cases, print the time it
took to run them.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
This patch adds SMP self-tests for the Secure Connections crypto
functions. The sample data has been taken from the core specification.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds self-tests for legacy SMP crypto functions. The sample
data has been taken from the core specification.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds the initial skeleton and kernel config option for SMP
self-tests.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Johan Hedberg