reduce the execution consumption of irrelevant code
testing the TX rates of TCP and UDP based on the Infineon board can
increase them by 13%.
Signed-off-by: zhanghongyu <zhanghongyu@xiaomi.com>
According rfc793 p69, In SYN-RCVD state, if the incoming segment is not acceptable, an acknowledgment should be sent in reply (unless the RST bit is set):
<SEQ=SND.NXT><ACK=RCV.NXT><CTL=ACK>
Signed-off-by: wenquan1 <wenquan1@xiaomi.com>
in the current process, if tcpstate is at TCP_FIN_WAIT_1, TCP_CLOSING,
and TCP_LAST_ACK, and the peer does not reply TCP_ACK, it will be
retransmitted permanently. to avoid continuous occupation of resources,
now when the retransmission equals TCP_MAXRTX, a reset message will be
sent and the conn resources will be reclaimed in tcp_close_work.
Signed-off-by: zhanghongyu <zhanghongyu@xiaomi.com>
shutdown should send TCP_FIN packet.
close should send TCP_RST packet when the data in readahead has not been
read and NEW_DATA has arrived.
send TCP_FIN packet when in other cases.
Signed-off-by: zhanghongyu <zhanghongyu@xiaomi.com>
the maximum retransmission interval allowed for car projects
cannot exceed 6 seconds, and allows for fixed retransmission intervals.
according to the previous algorithm, the retransmission interval
may be 0.5 * 2 ^ 4 = 8 seconds, which does not meet the requirements.
Signed-off-by: zhanghongyu <zhanghongyu@xiaomi.com>
CLOSE-WAIT - represents waiting for a connection termination request
from the local user.
TCP A TCP B
1. ESTABLISHED ESTABLISHED
2. (Close)
FIN-WAIT-1 --> <SEQ=100><ACK=300><CTL=FIN,ACK> --> CLOSE-WAIT
3. FIN-WAIT-2 <-- <SEQ=300><ACK=101><CTL=ACK> <-- CLOSE-WAIT
4. (Close)
TIME-WAIT <-- <SEQ=300><ACK=101><CTL=FIN,ACK> <-- LAST-ACK
5. TIME-WAIT --> <SEQ=101><ACK=301><CTL=ACK> --> CLOSED
6. (2 MSL)
CLOSED
in the current state, we can continue to send data until the user
calls shutdown or close, then directly enter the TCP_LAST_ACK state
Signed-off-by: zhanghongyu <zhanghongyu@xiaomi.com>
The TCP keep-alive implementation would send the probes and abort the
connection correctly, but without waking up the affected socket and
marking the connection as aborted. This patch from zhhyu7 in #16447
resolves the issue.
Signed-off-by: Matteo Golin <matteo.golin@gmail.com>
when accept conn timeout, only accept conn itself should handle the event
(send TCP_RESET), and there is no need to notify the listening conn.
otherwise, the server's poll will return with POLLERR and POLLHUP.
this may cause some applications to execute incorrect logic in the future.
Signed-off-by: zhanghongyu <zhanghongyu@xiaomi.com>
when tcp retransmission only double conn->timer in Karn(tcp_timer.c L602), after retransmission in Jacobson
M is is now rtt test will become a negative value.
```
signed char m;
m = conn->rto - conn->timer; // M is now rtt test
/* This is taken directly from VJs original code in his paper */
m = m - (conn->sa >> 3);
conn->sa += m; //conn->sa is a negative value
if (m < 0)
{
m = -m;
}
m = m - (conn->sv >> 2);
conn->sv += m;
conn->rto = (conn->sa >> 3) + conn->sv; //rto
```
For example,we lost one ack packet, we will set conn->timer = 6 by backoff，conn->rto still 3.
After retransmission we will Do RTT estimation, then will get
```
conn->sa = 253
conn->rto = 46
```
Then if any packets lost it will wait for a long time before triggering a retransmission.
Test method.
We can reproduce this issue by adding drop ACK packets in tcp_input, and debug conn->rto after Jacobson.
Signed-off-by: meijian <meijian@xiaomi.com>
Summary:
The conn->keeptimer units is decisecond，but its unit is treated as
half-second in the tcp_timer & tcp_get_timeout function.
Therefore conn>keeptimer needs to be divided by 5(DSEC_PER_HSEC)
to match half-second units.
Signed-off-by: zhangshuai39 <zhangshuai39@xiaomi.com>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
- NewReno congestion control algorithm is used to solve the problem
of network congestion breakdown. NewReno congestion control includes
slow start, collision avoidance, fast retransmission, and fast
recovery. The implementation refers to RFC6582 and RFC5681.
- In addition, we optimize the congestion algorithm. In the conflict
avoidance stage, the maximum congestion window max_cwnd is used to
limit the excessive growth of cwnd and prevent network jitter
caused by congestion. Maximum congestion window max_cwnd is updated
with the current congestion window cwnd and the update weight is
0.875 when an RTO timeout occurs.
Signed-off-by: liqinhui <liqinhui@xiaomi.com>
1. Remove tcp_txdrain() from close() to avoid indefinitely block
2. Send TCP_RST immediately if linger timeout
Signed-off-by: chao an <anchao@xiaomi.com>
tcp_sendfile() reads data directly from a file and does not use NET_TCP_WRITE_BUFFERS data flow
even if CONFIG_NET_TCP_WRITE_BUFFERS option is enabled.
Despite this, tcp_sendfile relied on NET_TCP_WRITE_BUFFERS specific flow control variables that
were idle during sendfile operation. Thus it was a total inconsistency.
E.g. because of the issue, TCP socket used by sendfile() operation never issued
FIN packet on close() command, and the TCP connection hung up.
As a result of the fix, simultaneously enabled CONFIG_NET_TCP_WRITE_BUFFERS and
CONFIG_NET_SENDFILE options can coexist.
tcp_timer: eliminated false decrements of conn->timer in case of multiple network adapters.
The false timer decrements sometimes provoked TCP spurious retransmissions due to premature timeouts.
reset the connection refcount if SYN retry count has elapsed
Assertion:
up_assert: Assertion failed at file:tcp/tcp_conn.c line: 764 task: netdev_wq
N/A
Signed-off-by: chao.an <anchao@xiaomi.com>
Fixes an issue where tcp sockets with activated keepalives stalled and
were not properly closed. Poll would not indicate a POLLHUP and therefore
locks down the application.
* tcp_conn_s.tcp_conn_s & tcp_conn_s.keepintvl changed to uint32_t
According RFC1122 keepidle MUST have a default of 2 hours.
Found by clang-check:
tcp/tcp_timer.c:185:15: warning: Value stored to 'result' is never read
result = tcp_callback(dev, conn, TCP_TIMEDOUT);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tcp/tcp_timer.c:264:23: warning: Value stored to 'result' is never read
result = tcp_callback(dev, listener, TCP_TIMEDOUT);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tcp/tcp_timer.c:300:19: warning: Value stored to 'result' is never read
result = tcp_callback(dev, conn, TCP_TIMEDOUT);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3 warnings generated.
Squashed commit of the following:
net/tmp: Rename the unacked field of the tcp connection structure to tx_unacked. Too confusing with the implementation of delayed RX ACKs.
net/tcp: Initial implementation of TCP delayed ACKs.
net/tcp: Add delayed ACK configuration selection. Rename tcp_ack() to tcp_synack(). It may or may not send a ACK. It will always send SYN or SYN/ACK.
net/tcp: Add logic to send probes when SO_KEEPALIVE is enabled.
net/tcp: TCP socket should not have to be connected to configure KeepAlive.
net/: Add a separate configuration to enable/disable KEEPALIVE socket options.
net/tcp: Arguments to TCP keep-alive timing functions probably should be struct timeval as are the times for other time-related socket options.
net/tcp: Fix a backward conditional
net/tcp: Add some more checks and debug output to TCP-protocol socket options.
net/tcp: Cosmetic changes to some alignment.
net/: Adds socket options needed to manage TCP-keepalive and TCP state machine logic to detect if that the remote peer is alive. Still missing the timer poll logic to send the keep-alive probes and the state machine logic to respond to probes.
