Commit Graph

3308 Commits

Author SHA1 Message Date
David S. Miller
51f3d02b98 net: Add and use skb_copy_datagram_msg() helper.
This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".

When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.

Having a helper like this means there will be less places to touch
during that transformation.

Based upon descriptions and patch from Al Viro.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-05 16:46:40 -05:00
Jukka Rissanen
9c238ca8ec Bluetooth: 6lowpan: Check transmit errors for multicast packets
We did not return error if multicast packet transmit failed.
This might not be desired so return error also in this case.
If there are multiple 6lowpan devices where the multicast packet
is sent, then return error even if sending to only one of them fails.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-10-02 13:41:57 +03:00
Jukka Rissanen
d7b6b0a532 Bluetooth: 6lowpan: Return EAGAIN error also for multicast packets
Make sure that we are able to return EAGAIN from l2cap_chan_send()
even for multicast packets. The error code was ignored unncessarily.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-10-02 13:41:39 +03:00
Jukka Rissanen
a7807d73a0 Bluetooth: 6lowpan: Avoid memory leak if memory allocation fails
If skb_unshare() returns NULL, then we leak the original skb.
Solution is to use temp variable to hold the new skb.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-10-02 13:41:32 +03:00
Jukka Rissanen
fc12518a4b Bluetooth: 6lowpan: Memory leak as the skb is not freed
The earlier multicast commit 36b3dd250d ("Bluetooth: 6lowpan:
Ensure header compression does not corrupt IPv6 header") lost one
skb free which then caused memory leak.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-10-02 13:41:30 +03:00
Johan Hedberg
02e246aee8 Bluetooth: Fix lockdep warning with l2cap_chan_connect
The L2CAP connection's channel list lock (conn->chan_lock) must never be
taken while already holding a channel lock (chan->lock) in order to
avoid lock-inversion and lockdep warnings. So far the l2cap_chan_connect
function has acquired the chan->lock early in the function and then
later called l2cap_chan_add(conn, chan) which will try to take the
conn->chan_lock. This violates the correct order of taking the locks and
may lead to the following type of lockdep warnings:

-> #1 (&conn->chan_lock){+.+...}:
       [<c109324d>] lock_acquire+0x9d/0x140
       [<c188459c>] mutex_lock_nested+0x6c/0x420
       [<d0aab48e>] l2cap_chan_add+0x1e/0x40 [bluetooth]
       [<d0aac618>] l2cap_chan_connect+0x348/0x8f0 [bluetooth]
       [<d0cc9a91>] lowpan_control_write+0x221/0x2d0 [bluetooth_6lowpan]
-> #0 (&chan->lock){+.+.+.}:
       [<c10928d8>] __lock_acquire+0x1a18/0x1d20
       [<c109324d>] lock_acquire+0x9d/0x140
       [<c188459c>] mutex_lock_nested+0x6c/0x420
       [<d0ab05fd>] l2cap_connect_cfm+0x1dd/0x3f0 [bluetooth]
       [<d0a909c4>] hci_le_meta_evt+0x11a4/0x1260 [bluetooth]
       [<d0a910eb>] hci_event_packet+0x3ab/0x3120 [bluetooth]
       [<d0a7cb08>] hci_rx_work+0x208/0x4a0 [bluetooth]

       CPU0                    CPU1
       ----                    ----
  lock(&conn->chan_lock);
                               lock(&chan->lock);
                               lock(&conn->chan_lock);
  lock(&chan->lock);

Before calling l2cap_chan_add() the channel is not part of the
conn->chan_l list, and can therefore only be accessed by the L2CAP user
(such as l2cap_sock.c). We can therefore assume that it is the
responsibility of the user to handle mutual exclusion until this point
(which we can see is already true in l2cap_sock.c by it in many places
touching chan members without holding chan->lock).

Since the hci_conn and by exctension l2cap_conn creation in the
l2cap_chan_connect() function depend on chan details we cannot simply
add a mutex_lock(&conn->chan_lock) in the beginning of the function
(since the conn object doesn't yet exist there). What we can do however
is move the chan->lock taking later into the function where we already
have the conn object and can that way take conn->chan_lock first.

This patch implements the above strategy and does some other necessary
changes such as using __l2cap_chan_add() which assumes conn->chan_lock
is held, as well as adding a second needed label so the unlocking
happens as it should.

Reported-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-10-02 10:37:07 +02:00
Jukka Rissanen
156395c998 Bluetooth: 6lowpan: Enable multicast support
Set multicast support for 6lowpan network interface.
This is needed in every network interface that supports IPv6.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-29 17:06:38 +02:00
Jukka Rissanen
36b3dd250d Bluetooth: 6lowpan: Ensure header compression does not corrupt IPv6 header
If skb is going to multiple destinations, then make sure that we
do not overwrite the common IPv6 headers. So before compressing
the IPv6 headers, we copy the skb and that is then sent to 6LoWPAN
Bluetooth devices.

This is a similar patch as what was done for IEEE 802.154 6LoWPAN
in commit f19f4f9525 ("ieee802154: 6lowpan: ensure header compression
does not corrupt ipv6 header")

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-29 17:06:38 +02:00
Jukka Rissanen
59790aa287 Bluetooth: 6lowpan: Make sure skb exists before accessing it
We need to make sure that the saved skb exists when
resuming or suspending a CoC channel. This can happen if
initial credits is 0 when channel is connected.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-29 10:10:02 +02:00
Johan Hedberg
565766b087 Bluetooth: Rename sco_param_wideband table to esco_param_msbc
The sco_param_wideband table represents the eSCO parameters for
specifically mSBC encoding. This patch renames the table to the more
descriptive esco_param_msbc name.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-25 10:35:08 +02:00
Johan Hedberg
c7da579763 Bluetooth: Add retransmission effort into SCO parameter table
It is expected that new parameter combinations will have the
retransmission effort value different between some entries (mainly
because of the new S4 configuration added by HFP 1.7), so it makes sense
to move it into the table instead of having it hard coded based on the
selected SCO_AIRMODE_*.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-24 22:15:29 +02:00
Johan Hedberg
d41c15cf95 Bluetooth: Fix reason code used for rejecting SCO connections
The core specification defines valid values for the
HCI_Reject_Synchronous_Connection_Request command to be 0x0D-0x0F. So
far the code has been using HCI_ERROR_REMOTE_USER_TERM (0x13) which is
not a valid value and is therefore being rejected by some controllers:

 > HCI Event: Connect Request (0x04) plen 10
	bdaddr 40:6F:2A:6A:E5:E0 class 0x000000 type eSCO
 < HCI Command: Reject Synchronous Connection (0x01|0x002a) plen 7
	bdaddr 40:6F:2A:6A:E5:E0 reason 0x13
	Reason: Remote User Terminated Connection
 > HCI Event: Command Status (0x0f) plen 4
	Reject Synchronous Connection (0x01|0x002a) status 0x12 ncmd 1
	Error: Invalid HCI Command Parameters

This patch introduces a new define for a value from the valid range
(0x0d == Connection Rejected Due To Limited Resources) and uses it
instead for rejecting incoming connections.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-24 14:03:32 +02:00
Joe Perches
2b0bf6c85a Bluetooth: Convert bt_<level> logging functions to return void
No caller or macro uses the return value so make all
the functions return void.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-24 09:40:08 +02:00
Bernhard Thaler
48e68ff5e5 Bluetooth: Check for SCO type before setting retransmission effort
SCO connection cannot be setup to devices that do not support retransmission.
Patch based on http://permalink.gmane.org/gmane.linux.bluez.kernel/7779 and
adapted for this kernel version.

Code changed to check SCO/eSCO type before setting retransmission effort
and max. latency. The purpose of the patch is to support older devices not
capable of eSCO.

Tested on Blackberry 655+ headset which does not support retransmission.
Credits go to Alexander Sommerhuber.

Signed-off-by: Bernhard Thaler <bernhard.thaler@r-it.at>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-23 11:30:04 +02:00
Johan Hedberg
5eb596f55c Bluetooth: Fix setting correct security level when initiating SMP
We can only determine the final security level when both pairing request
and response have been exchanged. When initiating pairing the starting
target security level is set to MEDIUM unless explicitly specified to be
HIGH, so that we can still perform pairing even if the remote doesn't
have MITM capabilities. However, once we've received the pairing
response we should re-consult the remote and local IO capabilities and
upgrade the target security level if necessary.

Without this patch the resulting Long Term Key will occasionally be
reported to be unauthenticated when it in reality is an authenticated
one.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
2014-09-18 17:39:37 +02:00
Marcel Holtmann
0097db06f5 Bluetooth: Remove exported hci_recv_fragment function
The hci_recv_fragment function is no longer used by any driver and thus
do not export it. In fact it is not even needed by the core and it can
be removed altogether.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-09-17 10:23:03 +03:00
Marcel Holtmann
43e73e4e2a Bluetooth: Provide HCI command opcode information to driver
The Bluetooth core already does processing of the HCI command header
and puts it together before sending it to the driver. It is not really
efficient for the driver to look at the HCI command header again in
case it has to make certain decisions about certain commands. To make
this easier, just provide the opcode as part of the SKB control buffer
information. The extra information about the opcode is optional and
only provided for HCI commands.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-09-15 07:15:45 +03:00
Marcel Holtmann
7cb9d20fd9 Bluetooth: Add BUILD_BUG_ON check for SKB control buffer size
The struct bt_skb_cb size needs to stay within the limits of skb->cb
at all times and to ensure that add a BUILD_BUG_ON to check for it at
compile time.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2014-09-15 07:15:41 +03:00
Johan Hedberg
9a783a139c Bluetooth: Fix re-setting RPA as expired when deferring update
The hci_update_random_address will clear the RPA_EXPIRED flag and
proceed with setting a new one if the flag was set. However, the
set_random_addr() function that is called may choose to defer the update
to a later moment. In such a case the flag would incorrectly remain
unset unless set_random_addr() re-sets it. This patch fixes the issue.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-12 18:34:25 +02:00
Johan Hedberg
7ed3fa2078 Bluetooth: Expire RPA if encryption fails
If encryption fails and we're using an RPA it may be because of a
conflict with another device. To avoid repeated failures the safest
action is to simply mark the RPA as expired so that a new one gets
generated as soon as the connection drops.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 07:32:14 +02:00
Johan Hedberg
5be5e275ad Bluetooth: Avoid hard-coded IO capability values in SMP
This is a trivial change to use a proper define for the NoInputNoOutput
IO capability instead of hard-coded values.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 03:02:22 +02:00
Johan Hedberg
aeaeb4bbca Bluetooth: Fix L2CAP information request handling for fixed channels
Even if we have no connection-oriented channels we should perform the
L2CAP Information Request procedures before notifying L2CAP channels of
the connection. This is so that the L2CAP channel implementations can
perform checks on what the remote side supports (e.g. does it support
the fixed channel in question).

So far the code has relied on the l2cap_do_start() function to initiate
the Information Request, however l2cap_do_start() is used on a
per-channel basis and only for connection-oriented channels. This means
that if there are no connection-oriented channels on the system we would
never start the Information Request procedure.

This patch creates a new l2cap_request_info() helper function to
initiate the Information Request procedure, and ensures that it is
called whenever a BR/EDR connection has been established. The patch also
updates fixed channels to be notified of connection readiness only once
the Information Request procedure has completed.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 02:45:24 +02:00
Johan Hedberg
a6f7833ca3 Bluetooth: Add smp_ltk_sec_level() helper function
There are several places that need to determine the security level that
an LTK can provide. This patch adds a convenience function for this to
help make the code more readable.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 02:45:24 +02:00
Johan Hedberg
1afc2a1ab6 Bluetooth: Fix SMP security level when we have no IO capabilities
When the local IO capability is NoInputNoOutput any attempt to convert
the remote authentication requirement to a target security level is
futile. This patch makes sure that we set the target security level at
most to MEDIUM if the local IO capability is NoInputNoOutput.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 02:45:24 +02:00
Johan Hedberg
24bd0bd94e Bluetooth: Centralize disallowing SMP commands to a single place
All the cases where we mark SMP commands as dissalowed are their
respective command handlers. We can therefore simplify the code by
always clearing the bit immediately after testing it. This patch
converts the corresponding test_bit() call to a test_and_clear_bit()
call and also removes the now unused SMP_DISALLOW_CMD macro.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 02:45:24 +02:00
Johan Hedberg
c05b9339c8 Bluetooth: Fix ignoring unknown SMP authentication requirement bits
The SMP specification states that we should ignore any unknown bits from
the authentication requirement. We already have a define for masking out
unknown bits but we haven't used it in all places so far. This patch
adds usage of the AUTH_REQ_MASK to all places that need it and ensures
that we don't pass unknown bits onward to other functions.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 02:45:24 +02:00
Johan Hedberg
3a7dbfb8ff Bluetooth: Remove unnecessary early initialization of variable
We do nothing else with the auth variable in smp_cmd_pairing_rsp()
besides passing it to tk_request() which in turn only cares about
whether one of the sides had the MITM bit set. It is therefore
unnecessary to assign a value to it until just before calling
tk_request(), and this value can simply be the bit-wise or of the local
and remote requirements.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-11 02:45:24 +02:00
Johan Hedberg
196332f5a1 Bluetooth: Fix allowing SMP Signing info PDU
If the remote side is not distributing its IRK but is distributing the
CSRK the next PDU after master identification is the Signing
Information. This patch fixes a missing SMP_ALLOW_CMD() for this in the
smp_cmd_master_ident() function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-10 01:45:01 +02:00
Jukka Rissanen
39e90c7763 Bluetooth: 6lowpan: Route packets that are not meant to peer via correct device
Packets that are supposed to be delivered via the peer device need to
be checked and sent to correct device. This requires that user has set
the routes properly so that the 6lowpan module can then figure out
the destination gateway and the correct Bluetooth device.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.17.x
2014-09-09 15:51:47 +02:00
Jukka Rissanen
b2799cec22 Bluetooth: 6lowpan: Set the peer IPv6 address correctly
The peer IPv6 address contained wrong U/L bit in the EUI-64 part.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.17.x
2014-09-09 15:51:47 +02:00
Jukka Rissanen
2ae50d8d3a Bluetooth: 6lowpan: Increase the connection timeout value
Use the default connection timeout value defined in l2cap.h because
the current timeout was too short and most of the time the connection
attempts timed out.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.17.x
2014-09-09 15:51:47 +02:00
Johan Hedberg
e1e930f591 Bluetooth: Fix mgmt pairing failure when authentication fails
Whether through HCI with BR/EDR or SMP with LE when authentication fails
we should also notify any pending Pair Device mgmt command. This patch
updates the mgmt_auth_failed function to take the actual hci_conn object
and makes sure that any pending pairing command is notified and cleaned
up appropriately.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-09 03:12:15 +02:00
Johan Hedberg
c68b7f127d Bluetooth: Fix dereferencing conn variable before NULL check
This patch fixes the following type of static analyzer warning (and
probably a real bug as well as the NULL check should be there for a
reason):

net/bluetooth/smp.c:1182 smp_conn_security() warn: variable dereferenced before check 'conn' (see line 1174)

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:57 +02:00
Behan Webster
9f06a8d623 Bluetooth: LLVMLinux: Remove VLAIS from bluetooth/amp.c
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch allocates the appropriate amount of memory
using an char array.

The new code can be compiled with both gcc and clang.

struct shash_desc contains a flexible array member member ctx declared with
CRYPTO_MINALIGN_ATTR, so sizeof(struct shash_desc) aligns the beginning
of the array declared after struct shash_desc with long long.

No trailing padding is required because it is not a struct type that can
be used in an array.

The CRYPTO_MINALIGN_ATTR is required so that desc is aligned with long long
as would be the case for a struct containing a member with
CRYPTO_MINALIGN_ATTR.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:56 +02:00
Johan Hedberg
b28b494366 Bluetooth: Add strict checks for allowed SMP PDUs
SMP defines quite clearly when certain PDUs are to be expected/allowed
and when not, but doesn't have any explicit request/response definition.
So far the code has relied on each PDU handler to behave correctly if
receiving PDUs at an unexpected moment, however this requires many
different checks and is prone to errors.

This patch introduces a generic way to keep track of allowed PDUs and
thereby reduces the responsibility & load on individual command
handlers. The tracking is implemented using a simple bit-mask where each
opcode maps to its own bit. If the bit is set the corresponding PDU is
allow and if the bit is not set the PDU is not allowed.

As a simple example, when we send the Pairing Request we'd set the bit
for Pairing Response, and when we receive the Pairing Response we'd
clear the bit for Pairing Response.

Since the disallowed PDU rejection is now done in a single central place
we need to be a bit careful of which action makes most sense to all
cases. Previously some, such as Security Request, have been simply
ignored whereas others have caused an explicit disconnect.

The only PDU rejection action that keeps good interoperability and can
be used for all the applicable use cases is to drop the data. This may
raise some concerns of us now being more lenient for misbehaving (and
potentially malicious) devices, but the policy of simply dropping data
has been a successful one for many years e.g. in L2CAP (where this is
the *only* policy for such cases - we never request disconnection in
l2cap_core.c because of bad data). Furthermore, we cannot prevent
connected devices from creating the SMP context (through a Security or
Pairing Request), and once the context exists looking up the
corresponding bit for the received opcode and deciding to reject it is
essentially an equally lightweight operation as the kind of rejection
that l2cap_core.c already successfully does.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:56 +02:00
Johan Hedberg
c6e81e9ae6 Bluetooth: Fix calling smp_distribute_keys() when still waiting for keys
When we're in the process of receiving keys in phase 3 of SMP we keep
track of which keys are still expected in the smp->remote_key_dist
variable. If we still have some key bits set we need to continue waiting
for more PDUs and not needlessly call smp_distribute_keys(). This patch
fixes two such cases in the smp_cmd_master_ident() and
smp_cmd_ident_addr_info() handler functions.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:56 +02:00
Johan Hedberg
88d3a8acf3 Bluetooth: Add define for key distribution mask
This patch adds a define for the allowed bits of the key distribution
mask so we don't have to have magic 0x07 constants throughout the code.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:56 +02:00
Johan Hedberg
fc75cc8684 Bluetooth: Fix locking of the SMP context
Before the move the l2cap_chan the SMP context (smp_chan) didn't have
any kind of proper locking. The best there existed was the
HCI_CONN_LE_SMP_PEND flag which was used to enable mutual exclusion for
potential multiple creators of the SMP context.

Now that SMP has been converted to use the l2cap_chan infrastructure and
since the SMP context is directly mapped to a corresponding l2cap_chan
we get the SMP context locking essentially for free through the
l2cap_chan lock. For all callbacks that l2cap_core.c makes for each
channel implementation (smp.c in the case of SMP) the l2cap_chan lock is
held through l2cap_chan_lock(chan).

Since the calls from l2cap_core.c to smp.c are covered the only missing
piece to have the locking implemented properly is to ensure that the
lock is held for any other call path that may access the SMP context.
This means user responses through mgmt.c, requests to elevate the
security of a connection through hci_conn.c, as well as any deferred
work through workqueues.

This patch adds the necessary locking to all these other code paths that
try to access the SMP context. Since mutual exclusion for the l2cap_chan
access is now covered from all directions the patch also removes
unnecessary HCI_CONN_LE_SMP_PEND flag (once we've acquired the chan lock
we can simply check whether chan->smp is set to know if there's an SMP
context).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:56 +02:00
Johan Hedberg
d6268e86a1 Bluetooth: Remove unnecessary deferred work for SMP key distribution
Now that the identity address update happens through its own deferred
work there's no need to have smp_distribute_keys anymore behind a second
deferred work. This patch removes this extra construction and makes the
code do direct calls to smp_distribute_keys() again.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:56 +02:00
Johan Hedberg
f3d82d0c8e Bluetooth: Move identity address update behind a workqueue
The identity address update of all channels for an l2cap_conn needs to
take the lock for each channel, i.e. it's safest to do this by a
separate workqueue callback.

Previously this was partially solved by moving the entire SMP key
distribution behind a workqueue. However, if we want SMP context locking
to be correct and safe we should always use the l2cap_chan lock when
accessing it, meaning even smp_distribute_keys needs to take that lock
which would once again create a dead lock when updating the identity
address.

The simplest way to solve this is to have l2cap_conn manage the deferred
work which is what this patch does. A subsequent patch will remove the
now unnecessary SMP key distribution work struct.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:55 +02:00
Johan Hedberg
84bc0db53b Bluetooth: Don't take any action in smp_resume_cb if not encrypted
When smp_resume_cb is called if we're not encrypted (i.e. the callback
wasn't called because the connection became encrypted) we shouldn't take
any action at all. This patch moves also the security_timer cancellation
behind this condition.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:55 +02:00
Johan Hedberg
1b0921d6be Bluetooth: Remove unnecessary checks after canceling SMP security timer
The SMP security timer used to be able to modify the SMP context state
but now days it simply calls hci_disconnect(). It is therefore
unnecessary to have extra sanity checks for the SMP context after
canceling the timer.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:55 +02:00
Johan Hedberg
434714dc02 Bluetooth: Add clarifying comment for LE CoC result value
The "pending" L2CAP response value is not defined for LE CoC. This patch
adds a clarifying comment to the code so that the reader will not think
there is a bug in trying to use this value for LE CoC.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:55 +02:00
Johan Hedberg
839035a7b3 Bluetooth: Move clock offset reading into hci_disconnect()
To give all hci_disconnect() users the advantage of getting the clock
offset read automatically this patch moves the necessary code from
hci_conn_timeout() into hci_disconnect(). This way we pretty much always
update the clock offset when disconnecting.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:55 +02:00
Johan Hedberg
e3f2f92a04 Bluetooth: Use hci_disconnect() for mgmt_disconnect_device()
There's no reason to custom build the HCI_Disconnect command in the
Disconnect Device mgmt command handler. This patch updates the code to
use hci_disconnect() instead.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:55 +02:00
Johan Hedberg
e3b679d56c Bluetooth: Update hci_disconnect() to return an error value
We'll soon use hci_disconnect() from places that are interested to know
whether the hci_send_cmd() really succeeded or not. This patch updates
hci_disconnect() to pass on any error returned from hci_send_cmd().

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:55 +02:00
Johan Hedberg
9b7b18ef1b Bluetooth: Fix SMP error and response to be mutually exclusive
Returning failure from the SMP data parsing function will cause an
immediate disconnect, making any attempts to send a response PDU futile.
This patch updates the function to always either send a response or
return an error, but never both at the same time:

* In the case that HCI_LE_ENABLED is not set we want to send a Pairing Not
  Supported response but it is not required to force a disconnection, so
  do not set the error return in this case.

* If we get garbage SMP data we can just fail with the handler function
  instead of also trying to send an SMP Failure PDU.

* There's no reason to force a disconnection if we receive an unknown SMP
  command. Instead simply send a proper Command Not Supported SMP
  response.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:54 +02:00
Johan Hedberg
b04afa0c28 Bluetooth: Remove unused l2cap_conn_shutdown API
Now that there are no more users of the l2cap_conn_shutdown API (since
smp.c switched to using hci_disconnect) we can simply remove it along
with all of it's l2cap_conn variables.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:54 +02:00
Johan Hedberg
1e91c29eb6 Bluetooth: Use hci_disconnect for immediate disconnection from SMP
Relying on the l2cap_conn_del procedure (triggered through the
l2cap_conn_shutdown API) to get the connection disconnected is not
reliable as it depends on all users releasing (through hci_conn_drop)
and that there's at least one user (so hci_conn_drop is called at least
one time).

A much simpler and more reliable solution is to call hci_disconnect()
directly from the SMP code when we want to disconnect. One side-effect
this has is that it prevents any SMP Failure PDU from being sent before
the disconnection, however neither one of the scenarios where
l2cap_conn_shutdown was used really requires this.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:54 +02:00
Johan Hedberg
e31fb86005 Bluetooth: Set discon_timeout to 0 in l2cap_conn_del
When the l2cap_conn_del() function is used we do not want to wait around
"in case something happens" before disconnecting. This patch sets the
disconnection timeout to 0 so that the disconnection routines get
immediately scheduled.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-09-08 19:07:54 +02:00