Segmentation and Reassembly (SAR) occupies different windows in standard and
extended control fields. Convert hardcoded masks to relative ones and use shift
to access SAR bits.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Supervisory bits occupy different windows in standard / extended control
fields. Convert hardcoded masks to relative ones and use shift to access
S-bit window.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Adds extended control field bit masks and rearrange defines to logical
groups: masks, flags and shift groups.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Adds support for extended window size (EWS) config option. We enable EWS
feature in L2CAP Info RSP when hs enabled. EWS option is included in L2CAP
Config Req if tx_win (which is set via socket) bigger then standard default
value (63) && hs enabled && remote side supports EWS feature.
Using EWS selects extended control field in L2CAP.
Code partly based on Qualcomm and Atheros patches sent upstream a year ago.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
role_switch variable inside l2cap_chan is a logical one and can
be easily converted to flag
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
force_active variable inside l2cap_chan is a logical one and can
be easily converted to flag
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
force_reliable variable inside l2cap_chan is a logical one and can
be easily converted to flag
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
flushable variable inside l2cap_chan is a logical one and can
be easily converted to flag. Added flags in l2cap_chan structure.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Use sk_buff fragment capabilities to link together incoming skbs
instead of allocating a new skb for reassembly and copying.
The new reassembly code works equally well for ERTM and streaming
mode, so there is now one reassembly function instead of two.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
The objective is to make the core to have as little as possible
information about SMP procedures and logic. Now, all the SMP
specific information is hidden from the core.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
There can 3 reasons for the "command reject" reply produced
by the stack. Each such reply should be accompanied by the
relevand data ( as defined in spec. ). Currently there is one
instance of "command reject" reply with reason "invalid cid"
wich is fixed. Also, added clean-up definitions related to the
"command reject" replies.
Signed-off-by: Ilia Kolomisnky <iliak@ti.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
The ERTM receive buffer is now handled in a way that does not require
the busy queue and the associated polling code.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This change moves most L2CAP ERTM receive buffer handling out of the
L2CAP core and in to the socket code. It's up to the higher layer
(the socket code, in this case) to tell the core when its buffer is
full or has space available. The recv op should always accept
incoming ERTM data or else the connection will go down.
Within the socket layer, an skb that does not fit in the socket
receive buffer will be temporarily stored. When the socket is read
from, that skb will be placed in the receive buffer if possible. Once
adequate buffer space becomes available, the L2CAP core is informed
and the ERTM local busy state is cleared.
Receive buffer management for non-ERTM modes is unchanged.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Instead of setting bits manually we use set_bit, test_bit, etc.
Also remove L2CAP_ prefix from macros.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This patch implements a check in smp cmd pairing request and pairing
response to verify if encryption key maximum size is compatible in both
slave and master when SMP Pairing is requested. Keys are also masked to
the correct negotiated size.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Anderson Briglia <anderson.briglia@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This patch adds support for disconnecting the link when SMP procedure
takes more than 30 seconds.
SMP begins when either the Pairing Request command is sent or the
Pairing Response is received, and it ends when the link is encrypted
(or terminated). Vol 3, Part H Section 3.4.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This patch includes support for generating and sending the random value
used to produce the confirmation value.
Signed-off-by: Anderson Briglia <anderson.briglia@openbossa.org>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This patch adds initial support for verifying the confirmation value
that the remote side has sent.
Signed-off-by: Anderson Briglia <anderson.briglia@openbossa.org>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
ERTM use the generic L2CAP timer functions to keep a reference to the
channel. This is useful for avoiding crashes.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
struct l2cap_chan has now its own refcnt that is compatible with the
socket refcnt, i.e., we won't see sk_refcnt = 0 and chan->refcnt > 0.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Now socket state is tracked by struct sock and channel state is tracked by
chan->state. At this point both says the same, but this is going to change
when we add AMP Support for example.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Add an abstraction layer between L2CAP core and its users (only
l2cap_sock.c now). The first function implemented is new_connection() that
replaces calls to l2cap_sock_alloc() in l2cap_core.c
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Add BT_POWER socket option used to control the power
characteristics of the underlying ACL link. When the remote end
has put the link in sniff mode and the host stack wants to send
data we need need to explicitly exit sniff mode to work well with
certain devices (For example, A2DP on Plantronics Voyager 855).
However, this causes problems with HID devices.
Hence, moving into active mode when sending data, irrespective
of who set the sniff mode has been made as a socket option. By
default, we will move into active mode. HID devices can set the
L2CAP socket option to prevent this from happening.
Currently, this has been implemented for L2CAP sockets. This has been
tested with incoming and outgoing L2CAP sockets for HID and A2DP.
Based on discussions on linux-bluetooth and patches submitted by
Andrei Emeltchenko.
Signed-off-by: Jaikumar Ganesh <jaikumar@google.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
The call to l2cap_chan_clear_timer() is not really needed in l2cap_sock.c.
This patch also adds a call to l2cap_chan_clear_timer() to the only place
in __l2cap_sock_close() that wasn't calling it. It's safe call it there
because l2cap_chan_clear_timer() check first for timer_peding().
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
The new timer does not belong to struct sock, tought it still touch some
sock things, but this will be sorted out soon.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
chan_type says if our chan is raw(direclty access to HCI),
connection less or connection oriented.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This move all the sending logic to l2cap_core.c, but we still have a
socket dependence there, struct msghdr. It will be removed in some of the
further commits.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This is actually __l2cap_sock_close() renamed to __l2cap_chan_close().
At a first look it may not make sense, but with the further cleanups that
will come it will.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
A new list was added to replace the socket based one. This new list
doesn't depent on sock and then fits better inside l2cap_core.c code.
It also rename l2cap_chan_alloc() to l2cap_chan_create() and
l2cap_chan_free() to l2cap_chan_destroy)
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
When the user doesn't specify a psm we have the choose one for the
channel. Now we do this inside l2cap_add_psm().
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
The intention is to get rid of the l2cap_sk_list usage inside
l2cap_core.c. l2cap_sk_list will soon be replaced by a list that does not
depend on socket usage.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
There is no need to the socket deal directly with the channel, most of the
time it cares about the channel only.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
In this commit, omtu, imtu, flush_to, mode and sport. It also remove the
pi var from l2cap_sock_sendmsg().
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
l2cap_chan_connect() is a much better name and reflects what this
functions is doing (or will do once socket dependence is removed from the
core).
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
If the allocation happens at l2cap_sock_create() will be able to use the
struct l2cap_chan to store channel info that comes from the user via
setsockopt.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This is part of "moving things to l2cap_chan". As one the first move it
triggered a big number of changes in the funcions parameters, basically
changing the struct sock param to struct l2cap_chan.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
As we use struct list_head to keep L2CAP channels list the workaround with
del_list is not needed anymore.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Use a well known Kernel API is always a good idea than implement your own
list.
In the future we might use RCU on this list.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
struct l2cap_chan cames to create a clear separation between what
properties and data belongs to the L2CAP channel and what belongs to the
socket. By now we just fold the struct sock * in struct l2cap_chan as all
the channel info is struct l2cap_pinfo today.
In the next commits we will see a move of channel stuff to struct
l2cap_chan.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Implements L2CAP Connection Parameter Update Response defined in
the Bluetooth Core Specification, Volume 3, Part A, section 4.21.
Address the LE Connection Parameter Procedure initiated by the slave.
Connection Interval Minimum and Maximum have the same range: 6 to
3200. Time = N * 1.25ms. Minimum shall be less or equal to Maximum.
The Slave Latency field shall have a value in the range of 0 to
((connSupervisionTimeout / connIntervalMax) - 1). Latency field shall
be less than 500. connSupervisionTimeout = Timeout Multiplier * 10 ms.
Multiplier field shall have a value in the range of 10 to 3200.
Signed-off-by: Claudio Takahasi <claudio.takahasi@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This patch splits the L2CAP command handling function in order to
have a clear separation between the commands related to BR/EDR and
LE. Commands and responses in the LE signaling channel are not being
handled yet, command reject is sent to all received requests. Bluetooth
Core Specification, Volume 3, Part A, section 4 defines the signaling
packets formats and allowed commands/responses over the LE signaling
channel.
Signed-off-by: Claudio Takahasi <claudio.takahasi@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Add support for LE server sockets.
Signed-off-by: Ville Tervo <ville.tervo@nokia.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Add basic LE connection support to L2CAP. LE
connection can be created by specifying cid
in struct sockaddr_l2
Signed-off-by: Ville Tervo <ville.tervo@nokia.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
l2cap_load() was added to trigger l2cap.ko module loading from the RFCOMM
and BNEP modules. Now that L2CAP module is gone, we don't need it anymore.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
It causes the move of the declaration of 3 functions to l2cap.h:
l2cap_get_ident(), l2cap_send_cmd(), l2cap_build_conf_req()
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This patch tries to do the minimal to move l2cap_sock_create() and its
dependencies to l2cap_sock.c. It create a API to initialize and cleanup
the L2CAP sockets from l2cap_core.c through l2cap_init_sockets() and
l2cap_cleanup_sockets().
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Modification of Nick Pelly <npelly@google.com> patch.
With Bluetooth 2.1 ACL packets can be flushable or non-flushable. This commit
makes ACL data packets non-flushable by default on compatible chipsets, and
adds the BT_FLUSHABLE socket option to explicitly request flushable ACL
data packets for a given L2CAP socket. This is useful for A2DP data which can
be safely discarded if it can not be delivered within a short time (while
other ACL data should not be discarded).
Note that making ACL data flushable has no effect unless the automatic flush
timeout for that ACL link is changed from its default of 0 (infinite).
Default packet types (for compatible chipsets):
Frame 34: 13 bytes on wire (104 bits), 13 bytes captured (104 bits)
Bluetooth HCI H4
Bluetooth HCI ACL Packet
.... 0000 0000 0010 = Connection Handle: 0x0002
..00 .... .... .... = PB Flag: First Non-automatically Flushable Packet (0)
00.. .... .... .... = BC Flag: Point-To-Point (0)
Data Total Length: 8
Bluetooth L2CAP Packet
After setting BT_FLUSHABLE
(sock.setsockopt(274 /*SOL_BLUETOOTH*/, 8 /* BT_FLUSHABLE */, 1 /* flush */))
Frame 34: 13 bytes on wire (104 bits), 13 bytes captured (104 bits)
Bluetooth HCI H4
Bluetooth HCI ACL Packet
.... 0000 0000 0010 = Connection Handle: 0x0002
..10 .... .... .... = PB Flag: First Automatically Flushable Packet (2)
00.. .... .... .... = BC Flag: Point-To-Point (0)
Data Total Length: 8
Bluetooth L2CAP Packet
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Remove extra spaces from legal text so that legal stuff looks
the same for all bluetooth code.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Do not initialize static vars to zero, macros with complex values
shall be enclosed with (), remove unneeded braces.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Change "return (EXPR);" to "return EXPR;"
return is not a function, parentheses are not required.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The previous value of 672 for L2CAP_DEFAULT_MAX_PDU_SIZE is based on
the default L2CAP MTU. That default MTU is calculated from the size
of two DH5 packets, minus ACL and L2CAP b-frame header overhead.
ERTM is used with newer basebands that typically support larger 3-DH5
packets, and i-frames and s-frames have more header overhead. With
clean RF conditions, basebands will typically attempt to use 1021-byte
3-DH5 packets for maximum throughput. Adjusting for 2 bytes of ACL
headers plus 10 bytes of worst-case L2CAP headers yields 1009 bytes
of payload.
This PDU size imposes less overhead for header bytes and gives the
baseband the option to choose 3-DH5 packets, but is small enough for
ERTM traffic to interleave well with other L2CAP or SCO data.
672-byte payloads do not allow the most efficient over-the-air
packet choice, and cannot achieve maximum throughput over BR/EDR.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The L2CAP specification requires that the ERTM retransmit timeout be at
least 2 seconds for BR/EDR connections.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To make net/ and include/net/ code consistent use __packed instead of
__attribute__ ((packed)). Bluetooth subsystem was one of the last net
subsys still using __attribute__ ((packed)).
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Copyright for the time I worked on L2CAP during the Google Summer of Code
program.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Using a lock to deal with the ERTM race condition - interruption with
new data from the hci layer - is wrong. We should use the native skb
backlog queue.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When mode is mandatory we shall not send connect request and report this
to the userspace as well.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
l2cap_ertm_send() can be called both from user context and bottom half
context. The socket locks for that contexts are different, the user
context uses a mutex(which can sleep) and the second one uses a
spinlock_bh. That creates a race condition when we have interruptions on
both contexts at the same time.
The better way to solve this is to add a new spinlock to lock
l2cap_ertm_send() and the vars it access. The other solution was to defer
l2cap_ertm_send() with a workqueue, but we the sending process already
has one defer on the hci layer. It's not a good idea add another one.
The patch refactor the code to create l2cap_retransmit_frames(), then we
encapulate the lock of l2cap_ertm_send() for some call. It also changes
l2cap_retransmit_frame() to l2cap_retransmit_one_frame() to avoid
confusion
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Supports Local Busy condition handling through a waitqueue that wake ups
each 200ms and try to push the packets to the upper layer. If it can
push all the queue then it leaves the Local Busy state.
The patch modifies the behaviour of l2cap_ertm_reassembly_sdu() to
support retry of the push operation.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With the sockopt extension we can set a per-channel MaxTx value.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that we can set the txWindow we need to change the acknowledgement
procedure to ack after each (pi->txWindow/6 + 1). The plus 1 is to avoid
the zero value.
It also renames pi->num_to_ack to a better name: pi->num_acked.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now we can set/get Transmission Window size via sockopt.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We were accepting values bigger than we can accept. This was leading
ERTM to drop packets because of wrong FCS checks.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We ack I-frames on each txWindow/5 I-frames received, but if the sender
stop to send I-frames and it's not a txWindow multiple we can leave some
frames unacked.
So I added a timer to ack I-frames on this case. The timer expires in
200ms.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
After receive a RR with P bit set ERTM shall use this funcion to choose
what type of frame to reply with F bit = 1.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
RejActioned is used to prevent retransmission when a entity is on the
WAIT_F state, i.e., waiting for a frame with F-bit set due local busy
condition or a expired retransmission timer. (When these two events raise
they send a frame with the Poll bit set and enters in the WAIT_F state to
wait for a frame with the Final bit set.)
The local entity doesn't send I-frames(the data frames) until the receipt
of a frame with F-bit set. When that happens it also set RejActioned to false.
RejActioned is a mandatory feature of ERTM spec.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
As specified by ERTM spec an ERTM channel can acknowledge received
I-frames(the data frames) by sending an I-frame with the proper ReqSeq
value (i.e. ReqSeq is set to BufferSeq). Until now we aren't setting the
ReqSeq value on I-frame control bits. That way we can save sending
S-frames(Supervise frames) only to acknowledge receipt of I-frames. It
is very helpful to the full-duplex channel.
ReqSeq is the packet sequence number sent in an acknowledgement frame to
acknowledge receipt of frames up to (ReqSeq - 1).
BufferSeq controls the receiver buffer, it is used to delay
acknowledgement of new frames to not cause buffer overflow. BufferSeq
value is not increased until frames are pulled by reassembly function.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Implement all issues related to RemoteBusy in the RECV state table.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Support for receiving of SREJ frames as specified by the state table.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When L2CAP loses an I-frame we send a SREJ frame to the transmitter side
requesting the lost packet. This patch implement all Recv I-frame events
on SREJ_SENT state table except the ones that deal with SendRej (the REJ
exception at receiver side is yet not implemented).
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Implement CRC16 check for L2CAP packets. FCS is used by Streaming Mode and
Enhanced Retransmission Mode and is a extra check for the packet content.
Using CRC16 is the default, L2CAP won't use FCS only when both side send
a "No FCS" request.
Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
L2CAP uses retransmission and monitor timers to inquiry the other side
about unacked I-frames. After sending each I-frame we (re)start the
retransmission timer. If it expires, we start a monitor timer that send a
S-frame with P bit set and wait for S-frame with F bit set. If monitor
timer expires, try again, at a maximum of L2CAP_DEFAULT_MAX_TX.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When receiving an I-frame with unexpected txSeq, receiver side start the
recovery procedure by sending a REJ S-frame to the transmitter side. So
the transmitter can re-send the lost I-frame.
This patch just adds a basic support for retransmission, it doesn't
mean that ERTM now has full support for packet retransmission.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
ERTM should use Segmentation and Reassembly to break down a SDU in many
PDUs on sending data to the other side.
On sending packets we queue all 'segments' until end of segmentation and
just the add them to the queue for sending. On receiving we create a new
SKB with the SDU reassembled.
Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for ERTM transfers, without retransmission, with
txWindow up to 63 and with acknowledgement of packets received. Now the
packets are queued before call l2cap_do_send(), so packets couldn't be
sent at the time we call l2cap_sock_sendmsg(). They will be sent in
an asynchronous way on later calls of l2cap_ertm_send(). Besides if an
error occurs on calling l2cap_do_send() we disconnect the channel.
Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Add support to config_req and config_rsp to configure ERTM and Streaming
mode. If the remote device specifies ERTM or Streaming mode, then the
same mode is proposed. Otherwise ERTM or Basic mode is used. And in case
of a state 2 device, the remote device should propose the same mode. If
not, then the channel gets disconnected.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To enable Enhanced Retransmission mode it needs to be set via a socket
option. A different mode can be set on a socket, but on listen() and
connect() the mode is checked and ERTM is only allowed if it is enabled
via the module parameter.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This adds the basic constants required to add support for L2CAP Enhanced
Retransmission feature.
Based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Using the L2CAP_CONF_HINT macro is easier to understand than using a
hardcoded 0x80 value.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Use macros instead of hardcoded numbers to make the L2CAP source code
more readable.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Some of the qualification tests demand that in case of failures in L2CAP
the HCI disconnect should indicate a reason why L2CAP fails. This is a
bluntly layer violation since multiple L2CAP connections could be using
the same ACL and thus forcing a disconnect reason is not a good idea.
To comply with the Bluetooth test specification, the disconnect reason
is now stored in the L2CAP connection structure and every time a new
L2CAP channel is added it will set back to its default. So only in the
case where the L2CAP channel with the disconnect reason is really the
last one, it will propagated to the HCI layer.
The HCI layer has been extended with a disconnect indication that allows
it to ask upper layers for a disconnect reason. The upper layer must not
support this callback and in that case it will nicely default to the
existing behavior. If an upper layer like L2CAP can provide a disconnect
reason that one will be used to disconnect the ACL or SCO link.
No modification to the ACL disconnect timeout have been made. So in case
of Linux to Linux connection the initiator will disconnect the ACL link
before the acceptor side can signal the specific disconnect reason. That
is perfectly fine since Linux doesn't make use of this value anyway. The
L2CAP layer has a perfect valid error code for rejecting connection due
to a security violation. It is unclear why the Bluetooth specification
insists on having specific HCI disconnect reason.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In preparation for L2CAP fixed channel support, the CID value of a
L2CAP connection needs to be accessible via the socket interface. The
CID is the connection identifier and exists as source and destination
value. So extend the L2CAP socket address structure with this field and
change getsockname() and getpeername() to fill it in.
The bind() and connect() functions have been modified to handle L2CAP
socket address structures of variable sizes. This makes them future
proof if additional fields need to be added.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the extended features mask indicates support for fixed channels,
request the list of available fixed channels. This also enables the
fixed channel features bit so remote implementations can request
information about it. Currently only the signal channel will be
listed.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the remote L2CAP server uses authentication pending stage and
encryption is enabled it can happen that a L2CAP connection request is
sent twice due to a race condition in the connection state machine.
When the remote side indicates any kind of connection pending, then
track this state and skip sending of L2CAP commands for this period.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When two L2CAP connections are requested quickly after the ACL link has
been established there exists a window for a race condition where a
connection request is sent before the information response has been
received. Any connection request should only be sent after an exchange
of the extended features mask has been finished.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In case the remote entity tries to negogiate retransmission or flow
control mode, reject it and fall back to basic mode.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth 1.2 specification introduced a specific features mask
value to interoperate with newer versions of the specification. So far
this piece of information was never needed, but future extensions will
rely on it. This patch adds a generic way to retrieve this information
only once per connection setup.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
After the change to the L2CAP configuration parameter handling the
global conf_mtu variable is no longer needed and so remove it.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
no code changes, just documenting existing types
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The L2CAP configuration parameter handling was missing the support
for rejecting unknown options. The capability to reject unknown
options is mandatory since the Bluetooth 1.2 specification. This
patch implements its and also simplifies the parameter parsing.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
