This patch moves all the disconn_cfm callbacks to be based on the hci_cb
list. This means making l2cap_disconn_cfm private to l2cap_core.c and
sco_conn_cb private to sco.c respectively. Since the hci_conn type
filtering isn't done any more on the wrapper level the callbacks
themselves need to check that they were passed a relevant type of
connection.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch moves all the connect_cfm callbacks to be based on the hci_cb
list. This means making l2cap_connect_cfm private to l2cap_core.c and
sco_connect_cb private to sco.c respectively. Since the hci_conn type
filtering isn't done any more on the wrapper level the callbacks
themselves need to check that they were passed a relevant type of
connection.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There's no reason to have the custom hci_proto_auth/encrypt_cfm helpers
when the hci_cb list works equally well. This patch adds L2CAP to the
hci_cb list and makes l2cap_security_cfm a private function of
l2cap_core.c.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
On BR/EDR the L2CAP channel instances for fixed channels have so far
been marked as ready only once the L2CAP information req/rsp procedure
is complete and we have the fixed channel mask. This could however lead
to data being dropped if we receive it on the channel before knowing the
remote mask.
Since it is valid for a remote to send data this early, simply assume
that the channel is supported when we receive data on it. So far this
hasn't been noticed much because of limited use of fixed channels on
BR/EDR, but e.g. with SMP over BR/EDR this is already now visible with
automated tests failing randomly.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The comparing of chan->src should always be done against the local
identity address, represented by hcon->src and hcon->src_type. This
patch modifies l2cap_global_fixed_chan() to take the full hci_conn so
that we can easily compare against hcon->src and hcon->src_type.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The current bdaddr_type() usage in l2cap_core.c is a bit funny in that
it's always passed a hci_conn + a hci_conn member. Because of this only
the hci_conn is really needed. Since the second parameter is always
either hcon->src_type or hcon->dst type this patch adds two helper
functions for each purpose: bdaddr_src_type() and bdaddr_dst_type().
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The devices address types are BR/EDR Public, LE Public and LE Random and
any of these three is valid for L2CAP connections. So show the correct
type in the debugfs list.
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>
Just use copy_from_iter(). That's what this method is trying to do
in all cases, in a very convoluted fashion.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
it'll die soon enough - now that kvec-backed iov_iter works regardless
of set_fs(), both instances will become copy_from_iter() as soon as
we introduce ->msg_iter...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The SMP over BR/EDR support for cross-transport pairing should also be
enabled when the debugfs setting force_lesc_support has been enabled.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
When doing SMP over BR/EDR some of the routines can be shared with the
LE functionality whereas others needs to be split into their own BR/EDR
specific branches. This patch implements the split of BR/EDR specific
SMP code from the LE-only code, making sure SMP over BR/EDR works as
specified.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To pave the way for future fixed channels to be added easily we should
track both the local and remote mask on a per-L2CAP connection (struct
l2cap_conn) basis. So far the code has used a global variable in a racy
way which anyway needs fixing.
This patch renames the existing conn->fixed_chan_mask that tracked
the remote mask to conn->remote_fixed_chan and adds a new variable
conn->local_fixed_chan to track the local mask. Since the HS support
info is now available in the local mask we can remove the
conn->hs_enabled variable.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth spec states that automatically flushable packets may not
be sent over a LE-U link.
Signed-off-by: Steven Walter <stevenrwalter@gmail.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
This patch adds some extra debug logs to L2CAP related code. These are
mainly to help track locking issues but will probably be useful for
debugging other types of issues as well.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The insufficient authentication/encryption errors indicate to the L2CAP
client that it should try to elevate the security level. Since there
really isn't any exception to this rule it makes sense to fully handle
it on the kernel side instead of pushing the responsibility to user
space.
This patch adds special handling of these two error codes and calls
smp_conn_security() with the elevated security level if necessary.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
So far smp_sufficient_security() has returned false if we're encrypted
with an STK but do have an LTK available. However, for the sake of LE
CoC servers we do want to let the incoming connection through even
though we're only encrypted with the STK.
This patch adds a key preference parameter to smp_sufficient_security()
with two possible values (enum used instead of bool for readability).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For LE CoC L2CAP servers we don't do security level elevation during the
BT_CONNECT2 state (instead LE CoC simply sends an immediate error
response if the security level isn't high enough). Therefore if we get a
security level change while an LE CoC channel is in the BT_CONNECT2
state we should simply do nothing.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There's no reason why all users of L2CAP would need to worry about
initializing chan->nesting to L2CAP_NESTING_NORMAL (which is important
since 0 is the same as NESTING_SMP). This patch moves the initialization
to the common place that's used to create all new channels, i.e. the
l2cap_chan_create() function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In the error case where credits is greater than max_credits there
is a missing l2cap_chan_unlock before returning.
Signed-off-by: Martin Townsend <mtownsend1973@gmail.com>
Tested-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The values of a lot of the mgmt_device_connected() parameters come
straight from a hci_conn object. We can simplify the function by passing
the full hci_conn pointer to it.
Signed-off-by: Alfonso Acosta <fons@spotify.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
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>
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>
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>
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>
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>
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>
It's natural to have *_get() functions that increment the reference
count of an object to return the object type itself. This way it's
simple to make a copy of the object pointer and increase the reference
count in a single step. This patch updates two such get() functions,
namely hci_conn_get() and l2cap_conn_get(), and updates the users to
take advantage of the new API.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that SMP has been converted to use fixed channels we've got a bit of
a problem with the hci_conn reference counting. So far the L2CAP code
has kept a reference for each L2CAP channel that was notified of the
connection. With SMP however this would mean that the connection is
never dropped even though there are no other users of it. Furthermore,
SMP already does its own hci_conn reference counting internally,
starting from a security or pairing request and ending with the key
distribution.
This patch makes L2CAP fixed channels default to the L2CAP core not
keeping a hci_conn reference for them. A new FLAG_HOLD_HCI_CONN flag is
added so that L2CAP users can declare an exception to this rule and hold
a reference even for their fixed channels. One such exception is the
L2CAP socket layer which does want a reference for each socket (e.g. an
ATT socket which uses a fixed channel).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The l2cap_chan_add() function doesn't require the channel to be
unlocked. It only requires the l2cap_conn to be unlocked. Therefore,
it's unnecessary to unlock a channel before calling l2cap_chan_add().
This patch removes such unnecessary unlocking from the
l2cap_chan_connect() function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The l2cap_create_le_flowctl_pdu() function that l2cap_segment_le_sdu()
calls is perfectly capable of doing packet fragmentation if given bigger
PDUs than the HCI buffers allow. Forcing the PDU length based on the HCI
MTU (conn->mtu) would therefore needlessly strict operation on hardware
with limited LE buffers (e.g. both Intel and Broadcom seem to have this
set to just 27 bytes).
This patch removes the restriction and makes it possible to send PDUs of
the full length that the remote MPS value allows.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
I-Frame which is going to be resend already has FCS field added and set
(if it was required). Adding additional FCS field calculated from data +
old FCS in resend function is incorrect. This patch fix that.
Issue has been found during PTS testing.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There is no need to decrease pdu size with L2CAP SDU lenght in Start
L2CAP SDU frame. Start packtet is just 2 bytes longer as specified and
we can keep payload as long as possible.
When testing SAR L2CAP against PTS, L2CAP channel is usually configured
in that way, that SDU = MPS * 3. PTS expets then 3 I-Frames from IUT: Start,
Continuation and End frame.
Without this fix, we sent 4 I-Frames. We could pass a test by using -b
option in l2test and send just two bytes less than SDU length. With this
patch no need to use -b option.
Signed-off-by: Lukasz Rymanowski <lukasz.rymanowski@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that there are no-longer any users for l2cap_conn->security_timer we
can go ahead and simply remove it. The patch makes initialization of the
conn->info_timer unconditional since it's better not to leave any
l2cap_conn data structures uninitialized no matter what the underlying
transport.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Since we no-longer do special handling of SMP within l2cap_core.c we
don't have any code for calling l2cap_conn_del() when smp.c doesn't like
the data it gets. At the same time we cannot simply export
l2cap_conn_del() since it will try to lock the channels it calls into
whereas we already hold the lock in the smp.c l2cap_chan callbacks (i.e.
it'd lead to a deadlock).
This patch adds a new l2cap_conn_shutdown() API which is very similar to
l2cap_conn_del() except that it defers the call to l2cap_conn_del()
through a workqueue, thereby making it safe to use it from an L2CAP
channel callback.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There's no need to export the smp_distribute_keys() function since the
resume callback is called in the same scenario. This patch makes the
smp_notify_keys function private (at the same time moving it higher up
in smp.c to avoid forward declarations) and adds a resume callback for
SMP to call it from there instead.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that we have all the necessary pieces in place we can fully convert
SMP to use the L2CAP channel infrastructure. This patch adds the
necessary callbacks and removes the now unneeded conn->smp_chan pointer.
One notable behavioral change in this patch comes from the following
code snippet:
- case L2CAP_CID_SMP:
- if (smp_sig_channel(conn, skb))
- l2cap_conn_del(conn->hcon, EACCES);
This piece of code was essentially forcing a disconnection if garbage
SMP data was received. The l2cap_conn_del() function is private to
l2cap_conn.c so we don't have access to it anymore when using the L2CAP
channel callbacks. Therefore, the behavior of the new code is simply to
return errors in the recv() callback (which is simply the old
smp_sig_channel()), but no disconnection will occur.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For most cases it makes no difference whether l2cap_le_conn_ready() is
called before or after calling the channel ready() callbacks, however
for upcoming SMP code we need this as the ready() callback initializes
certain structures that a call to smp_conn_security() from
l2cap_le_conn_ready() depends on. Therefore, move the call to
l2cap_le_conn_ready() after iterating through and notifying channels.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
L2CAP channel implementations may want to still access the chan->conn
pointer. This will particularly be the case for SMP that will want to
clear a reference to the SMP channel in the l2cap_conn structure. The
only user of the teardown callback so far is l2cap_sock.c and for the
code there it makes no difference whether the callback is called before
or after clearing the chan->conn pointer.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The l2cap_add_scid function is used for registering a fixed L2CAP
channel. Instead of having separate initialization of the channel type
and outgoing MTU in l2cap_sock.c it's more intuitive to do these things
in the l2cap_add_scid function itself (and thereby make the
functionality available to other users besides l2cap_sock.c).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that we've got the fixed channel infrastructure cleaned up in a
generic way there's no longer a need to have a dedicated function for
handling data on the ATT channel. Instead the generic
l2cap_data_channel() handler will be able to do the exact same thing.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When notifying global fixed channels of new connections it doesn't make
sense to consider channels meant for a different link type than the one
available. This patch adds an extra parameter to the
l2cap_global_fixed_chan() lookup function and ensures that only channels
matching the current hci_conn type are looked up.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In order to remove special handling of fixed L2CAP channels we need to
start creating them in a single place instead of having per-channel
exceptions. The most natural place is the l2cap_conn_cfm() function
which is called whenever there is a new baseband link.
The only really special case so far has been the ATT socket, so in order
not to break the code in between this patch removes the ATT special
handling at the same time as it adds the generic fixed channel handling
from l2cap_le_conn_ready() into the hci_conn_cfm() function. As a
related change the channel locking in l2cap_conn_ready() becomes simpler
and we can thereby move the smp_conn_security() call into the
l2cap_le_conn_ready() function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch is a simple refactoring of l2cap_connect_cfm to allow easier
extension of the function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With the update to sk->resume() and __l2cap_no_conn_pending() we
no-longer need to have special handling of ATT channels in the
l2cap_security_cfm() function. The chan->sec_level update when
encryption has been enabled is safe to do for any kind of channel, and
the loop takes later care of calling chan->ready() or chan->resume() if
necessary.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The __l2cap_no_conn_pending() function would previously only return a
meaningful value for connection oriented channels and was therefore not
useful for anything else. As preparation of making the L2CAP code more
generic allow the function to be called for other channel types as well
by returning a meaningful value for them.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When looking up entries from the global L2CAP channel list there needs
to be a guarantee that other code doesn't go and remove the entry after
a channel has been returned by the lookup function. This patch makes
sure that the channel reference is incremented before the read lock is
released in the global channel lookup functions. The patch also adds the
corresponding l2cap_chan_put() calls once the channels pointers are
no-longer needed.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
