L2CAP ERTM sockets can be opened with the SOCK_STREAM socket type,
which is a mandatory request for ERTM mode.
However, these sockets still have SOCK_SEQPACKET read semantics when
bt_sock_recvmsg() is used to pull data from the receive queue. If the
application is only reading part of a frame, then the unread portion
of the frame is discarded. If the application requests more bytes
than are in the current frame, only the current frame's data is
returned.
This patch utilizes common code derived from RFCOMM's recvmsg()
function to make L2CAP SOCK_STREAM reads behave like RFCOMM reads (and
other SOCK_STREAM sockets in general). The application may read one
byte at a time from the input stream and not lose any data, and may
also read across L2CAP frame boundaries.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Valid L2CAP PSMs are odd numbers, and the least significant bit of the
most significant byte must be 0.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
L2CAP doesn't permit change like MTU, FCS, TxWindow values while the
connection is alive, we can only set that before the
connection/configuration process. That can lead to bugs in the L2CAP
operation.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This reverts commit 8cb8e6f168.
That commit introduced a regression with the Bluetooth Profile Tuning
Suite(PTS), Reverting this make sure that L2CAP is in a qualificable
state.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
As we don't have any error control on the Streaming mode, i.e., we don't
need to keep a copy of the skb for later resending we don't need to
call skb_clone() on it.
Then we can go one further here, and dequeue the skb before sending it,
that also means we don't need to look to sk->sk_send_head anymore.
The patch saves memory and time when sending Streaming mode data, so
it is good to mainline.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
When receiving L2CAP negative configuration response with respect
to MTU parameter we modify wrong field. MTU here means proposed
value of MTU that the remote device intends to transmit. So for local
L2CAP socket it is pi->imtu.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Acked-by: Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
This fixes a bug which caused the FCS setting to show L2CAP_FCS_CRC16
with L2CAP modes other than ERTM or streaming. At present, this only
affects the FCS value shown with getsockopt() for basic mode.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
remote_tx_win is intended to be set on receipt of an L2CAP
configuration request. The value is used to determine the size of the
transmit window on the remote side of an ERTM connection, so L2CAP
can stop sending frames when that remote window is full.
An incorrect remote_tx_win value will cause the stack to not fully
utilize the tx window (performance impact), or to overfill the remote
tx window (causing dropped frames or a disconnect).
This patch removes an extra setting of remote_tx_win when a
configuration response is received. The transmit window has a
different meaning in a response - it is an informational value
less than or equal to the local tx_win.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Incoming configuration values must be converted to native CPU order
before use. This fixes a bug where a little-endian MPS value is
compared to a native CPU value. On big-endian processors, this
can cause ERTM and streaming mode segmentation to produce PDUs
that are larger than the remote stack is expecting, or that would
produce fragmented skbs that the current FCS code cannot handle.
Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Check result code of L2CAP information response. Otherwise
it would read invalid feature mask and access invalid memory.
Signed-off-by: Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the remote side doesn't support Enhanced Retransmission Mode neither
Streaming Mode, we shall not send the RFC option.
Some devices that only supports Basic Mode do not understanding the RFC
option. This patch fixes the regression found with these devices.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Change the enable_ertm param to disable_ertm and default value to 0. That
means that L2CAP Extended features are enabled by default now.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We did some changes on the L2CAP configuration process and its behaviour
is bit different now. That justifies a updated on the L2CAP version.
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>
Purely a cosmetic change, it doesn't change the code flow.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Probably a typo error. We were using the wrong struct to get size.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The extended L2CAP features requires that one should initiate a
ConfigReq after send the ConnectionRsp. This patch changes the behaviour
of the configuration process of our stack.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
L2CAP only deals with ACL links. EINVAL should be returned otherwise.
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When the socket is in a bad state EBADFD is more appropriate then EINVAL.
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When we try to send a message bigger than the outgoing MTU value
EMSGSIZE (message too long) should be returned.
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
It doesn't make sense to have a return value since we always set it
to 0.
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Return a proper error value if socket is already connected.
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now we also check if can push skb userspace just after receive a new
skb instead of only wait the l2cap_busy_work wake up from time to time
to check the local busy condition.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
backlog queue is the canonical mechanism to avoid race conditions due
interrupts in bottom half context. After the socket lock is released the
net core take care of push all skb in its backlog queue.
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>
If such event happens we shall reply with a Command Reject, because we are
not expecting any configure request.
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>
Since now we have checks for the supported mode before on
l2cap_info_rsp we can remove the check for it here.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If our mode is Basic Mode we have to refuse any ConfigRsp that proposes
a different mode.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Profile Tuning Suite requires that we send a RFC containing the
Basic Mode configuration when requesting Basic Mode.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If we choose to use Basic Mode then we have to refuse the received mode
and propose Basic Mode again.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the device is a STATE 2 then it should disconnect the channel if the
remote device propose a mode different from its mandatory mode.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the socket type is SOCK_STREAM we set Enhanced Retransmisson Mode or
Streaming Mode as mandatory. That means that we will close the channel
if the other side doesn't support or request the the mandatory mode.
Basic mode can't be set as mandatory.
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>
l2cap_send_sframe() already set the F-bit if we set L2CAP_CONN_SEND_FBIT
and unset L2CAP_CONN_SEND_FBIT after send the F-bit.
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>
If any error occurs during transfers we have to tell userspace that
something wrong happened.
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>
The Bluetooth SIG Profile Tuning Suite Software uses the CSA1 spec
to run the L2CAP tests. The new 3.0 spec has a missing
Retransmit-I-Frames action when the Remote side is Busy.
We still start the retransmission timer if Remote is Busy and unacked
frames > 0. We do everything we did before this change plus the
Retransmission of I-frames.
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>
This way, if FCS is enabled and the packet is corrupted, we just drop it
without read it len, which could be corrupted.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We have to check if the proposed tx_window value is not greater that
maximum value supported.
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>
ERTM spec mandates that after receive a P-bit we shall send an F-bit in
response. This patch fixes this for retransmitted packets, on
retransmitting we were missing to check for a pending F-bit to be sent.
Also we were missing some annotation to send a F-bit.
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>
Updating buffer_seq first make us able to ack the last I-frame received.
This is also a requirement of the Profile Tuning Suite software.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The ack_timer is implemation specific, disabling it in such situation
avoids some potencial errors in the ERTM protocol.
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>
When resending an I-frame, ERTM was reusing the control bits from the last
time it was sent, that was causing a corruption in the new control field
due to it dirty fields.
This patches extracts only the SAR bits from the old field and reuse it to
resend the packet, the others bits should be reset and receive the
updated value.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Fix a crash regarding the Monitor Timeout, it was running even after the
shutdown of the ACL connection, which doesn't make sense.
The same code also fixes another issue, before this patch L2CAP was sending
many Disconnections Requests while we have to send only one.
The issues are related to each other, a expired Monitor Timeout can
trigger a Disconnection Request and then we may have a crash if the link
was already deleted.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
ERTM and streaming mode L2CAP sockets have no minimum packet length. Only
basic mode connections have minimum length.
Instead, validate the packet containing all necessary control, FCS,
and SAR fields.
The patch fixes the drop of valid packets with length lower than 4.
Signed-off-by: Nathan Holstein <ngh@isomerica.net>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Since all TxSeq values are modulo, we shall not compare them directly. We
have to compare their offset inside the TxWindow instead.
Signed-off-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch makes l2cap_ertm_send() similar to the Send-Data action of
the ERTM spec. We shall not check for RemoteBusy or WAIT_F state
inside l2cap_ertm_send().
Such checks were causing a bug in the retransmission logic of ERTM and
making ERTM stalls until the ACL is dropped.
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>
