We usually cannot use context->local for established TCP connections
because the local address is not updated for TCP if we are bound to
any address. So create helper that try to figure out the end point
addresses.
Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
When a TCP connection is established, if there is no data exchange
between the two parties within the set time, the side that enables
TCP Keep-alive will send a TCP probe packet with the same sequence
number as the previous TCP packet. This TCP probe packet is an empty
ACK packet (the specification recommends that it should not contain
any data, but can also contain 1 nonsense byte, such as 0x00.). If
there is no response from the other side after several consecutive
probe packets are sent, it is determined that the tcp connection has
failed, and the connection is closed.
The keep-alive default parameters are aligned with Linux defaults.
Signed-off-by: Horse Ma <mawei@coltsmart.com>
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
Rework how data is queued for the TCP connections:
* net_context no longer allocates net_pkt for TCP connections. This
was not only inefficient (net_context has no knowledge of the TX
window size), but also error-prone in certain configuration (for
example when IP fragmentation was enabled, net_context may attempt
to allocate enormous packet, instead of let the data be fragmented
for the TCP stream.
* Instead, implement already defined `net_tcp_queue()` API, which
takes raw buffer and length. This allows to take TX window into
account and also better manage the allocated net_buf's (like for
example avoid allocation if there's still room in the buffer). In
result, the TCP stack will not only no longer exceed the TX window,
but also prevent empty gaps in allocated net_buf's, which should
lead to less out-of-mem issues with the stack.
* As net_pkt-based `net_tcp_queue_data()` is no longer in use, it was
removed.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
Modify internal L4 protocols APIs, to allow to enforce checksum
calculation, regardless of the checksum HW offloading capability.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
Add a helper function which allows to send a RST packet in response to
an unexpected TCP packet, w/o associated connection or net context.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
rand32.h does not make much sense, since the random subsystem
provides more APIs than just getting a random 32 bits value.
Rename it to random.h and get consistently with other
subsystems.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Added a feature of socket connect
being asynchronous. If socket is set
to nonblock with O_NONBLOCK flag,
then connect() is non-blocking aswell.
App can normally poll the socket to
test when the connection is established.
Signed-off-by: Daniel Nejezchleb <dnejezchleb@hwg.cz>
There is a pending TODO regarding unifying net_tcp_unref() and
net_tcp_put(). Given that net_tcp_unref() is no longer used by the upper
layer (it should only use get/put APIs), the function can be removed
from external TCP API, as referencing/dereferencing is now only used
internally by the TCP stack.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
To improve the performance with small chunks send, implement Nagle's
algorithm. Provide the option TCP_NODELAY to disable the algorithm.
Signed-off-by: Sjors Hettinga <s.a.hettinga@gmail.com>
In the existing the value received from the other side by the TCP options
is used as MSS for transmission. Since the MSS options are an
announcement rather then a negotionation, it is likely the receiver will
have a different and possibly bigger MSS than allowed by our side.
This allow potentially for different a MSS in the receive and transmit
path.
Directly using the received MSS could cause problems when our MSS is only
allowed to be small. At transmission, for that reason take the minimum of
the received MSS and our desired MSS to find a value compatible to both
sides of the link.
Rename the function to net_tcp_get_recv_mss to net_tcp_get_supported_mss
to better reflect its function in the new situation.
Signed-off-by: Sjors Hettinga <s.a.hettinga@gmail.com>
The semaphore is reset when TCP layer would normally reject transfer
request (either due to TX window being full or entering retransmission
mode). Once data is acnowledged, or the reatransmission is done, the
semaphore is set again.
Upper layers can monitor the semaphore with `k_poll()` instead of
waiting blindly before attempting to transmit again.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
In order to bring consistency in-tree, migrate all subsystems code to
the new prefix <zephyr/...>. Note that the conversion has been scripted,
refer to zephyrproject-rtos#45388 for more details.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
TCP2 is no longer needed as it is the unique implementation since the
legacy one has been removed.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Remove legacy TCP stack as it is replaced by the new TCP2 stack.
The TCP2 stack has been the default stack since 2.4 release.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Comment out TCP1 specific stuff when TCP2 is enabled. This means
shuffling the code around a bit so that common code is placed at
the end. Introduce also net_tcp_foreach() function to TCP2 so that
it can be used from net-shell.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Unit tests were failing to build because random header was included by
kernel_includes.h. The problem is that rand32.h includes a generated
file that is either not generated or not included when building unit
tests. Also, it is better to limit the scope of this file to where it is
used.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Allow user to disable native IP stack and use offloaded IP
stack instead. It is also possible to enable both at the same
time if needed.
Fixes#18105
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
And also to the relevant callbacks.
That parameter is not used anywhere so it is useless.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Make sure that network related functions are always documented.
This means keeping the prototype and possible stub together.
Fixes#12615
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
It is now useless as the only function using it
(net_pkt_set_appdata_values) got removed.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
As we are adding more protocol families and protocol types
to connection handlers, some values might be same across
different types. Current connection handler only stores
proto type to match the handler, which is not enough if
we add more types. Also combination of family and types
may vary too. So adding family to connection handler to
figure out best match.
Also changing proto variable in net_conn from u8_t to u16_t.
net_context has 16 bit proto.
Signed-off-by: Ravi kumar Veeramally <ravikumar.veeramally@linux.intel.com>
Only next to be removed functions like net_tcp_set_checksum() are left
untouched. All the rest is switched.
Adding net_tcp_finalize() to follow the same logic as for UDP and else.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
This proovse to drastically reduce runtime overhead as it does not need
to parse IP nor TCP header all over again in a lot of places.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
These were at most set, but never used. They appear to be artifacts
of importing code from the FNET stack.
Addresses: #9570
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Move struct members around in networking code so that we avoid
unnecessary holes inside structs. No functionality changes by
this commit.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Similar to UDP, some drivers can make use of the following functions:
net_tcp_get_hdr()
net_tcp_set_hdr()
Let's expose them as <net/tcp.h> and change all internal references
to "tcp_internal.h".
Signed-off-by: Michael Scott <michael@opensourcefoundries.com>
Move core TCP functionality from net_context.c to tcp.c. Create empty
functions that the compiler can remove if TCP is not configured. As a
result remove TCP ifdefs from net_context.
Signed-off-by: Patrik Flykt <patrik.flykt@intel.com>
Queue a TCP FIN packet when needed if the socket was connected or
listening and where FIN wasn't already received.
Signed-off-by: Patrik Flykt <patrik.flykt@intel.com>
With CONFIG_NET_TCP is not set, provide empty static inline
prototypes for all TCP functions available to other parts of
the IP stack.
Signed-off-by: Patrik Flykt <patrik.flykt@intel.com>
If context is bound to IPv6 unspecified addresss and some port
number, then unspecified address is passed in TCP reset packet
message preparation. Eventually packet dropped at the peer.
Signed-off-by: Ravi kumar Veeramally <ravikumar.veeramally@linux.intel.com>
This field is set and maintained, but not actually used for anything.
The only purpose for it would be to validate ACK numbers from peer,
but such a validation is now implemented by using send_seq field
directly.
Fixes: #4653
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Per RFC 793:
A new acknowledgment (called an "acceptable ack"), is one for which
the inequality below holds:
SND.UNA < SEG.ACK =< SND.NXT
If acknowledgement is received for sequence number which wasn't yet
sent, log an error and ignore it.
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Right now in FIN_WAIT1 state, if we receive FIN+ACK message, then
tcp state changed to FIN_WAIT2 on ACK flag and immediately on FIN
flag state changed to TIME_WAIT. Then final ACK is prepared and sent
(in queue at-least) to peer. Again immediately state changed to
TCP_CLOSED, where context is freed. net_context_put frees context
and releases tcp connection. Final ACK packet which is in queue
is dropped.
As a side effect of freed ACK packet, peer device keep on sending
FIN+ACK messages (that's why we see a lot of "TCP spurious
retransimission" messages in wireshark). As a result
of context free (respective connection handler also removed), we see
lot of packets dropped at connection input handler and replying with
ICMP error messages (destination unreachable).
To fix this issue, timewait timer support is required. When tcp
connection state changed to TIMEWAIT state, it should wait until
TIMEWAIT_TIMETOUT before changing state to TCP_CLOSED. It's
appropriate to close the tcp connection after timewait timer expiry.
Note: Right now timeout value is constant (250ms). But it should
be 2 * MSL (Maximum segment lifetime).
Signed-off-by: Ravi kumar Veeramally <ravikumar.veeramally@linux.intel.com>
Add a generic function for TCP option parsing. So far we're
interested only in MSS option value, so that's what it handles.
Use it to parse MSS value in net_context incoming SYN packet
handler.
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Calculates full TCP header length (with options). Macro introduced
for reuse, to avoid "magic formula". (E.g., it would be needed to
parse TCP options).
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
MSS is Maximum Segment Size (data payload) of TCP. In SYN packets,
each side of the connection shares an MSS it wants to use (receive)
via the corresponding TCP option. If the option is not available,
the RFC mandates use of the value 536.
This patch handles storage of the send MSS (in the TCP structure,
in TCP backlog), with follow up patch handling actual parsing it
from the SYN TCP options.
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
The expire function can call net_context_unref() which tries to
get a semaphore with K_FOREVER. This is not allowed in interrupt
context. To overcome this, run the expire functionality from
system work queue instead.
Fixes#4683
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
The net_tcp_get/set_hdr() and net_udp_get/set_hdr() documentation
was not clear in corresponding header file. Clarify how the return
value of the function is supposed to be used.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>