fix build break if enable CONFIG_NET_IPv6 only
In file included from tcp/tcp_sendfile.c:38:
tcp/tcp_sendfile.c: In function ‘sendfile_eventhandler’:
tcp/tcp_sendfile.c:173:27: error: ‘struct tcp_conn_s’ has no member named ‘domain’
173 | DEBUGASSERT(conn->domain == PF_INET6);
| ^~
Signed-off-by: chao an <anchao@xiaomi.com>
Fixed by commit:
| net: remove pvconn reference from all devif callback
|
| Do not use 'pvconn' argument to get the connection pointer since
| pvconn is normally NULL for some events like NETDEV_DOWN.
| Instead, the connection pointer can be reliably obtained from the
| corresponding private pointer.
Signed-off-by: chao an <anchao@xiaomi.com>
since it is impossible to track producer and consumer
correctly if TCP/IP stack pass IOB directly to netdev
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
fix regression of invalid update the rexmit_seq in buffer mode
rexmit_seq should not be used instead of sndseq in fast retransmission,
sndseq of retransmission in the packet does not need to be re-updated
Signed-off-by: chao.an <anchao@xiaomi.com>
Retransmit only one the earliest not acknowledged segment
(according to RFC 6298 (5.4)). The issue is the same as it was
in tcp_send_unbuffered.c and tcp_sendfile.c.
Signed-off-by: chao.an <anchao@xiaomi.com>
According to RFC 5681 (3.2) the TCP Fast Retransmit algorithm should start
if the threshold of 3 duplicate ACKs is reached.
Thus the threshold should be a constant, not an integer option.
Do not use pvconn argument to get the TCP connection pointer because pvconn is
normally NULL for some events like NETDEV_DOWN. Instead, the TCP connection pointer
can be reliably obtained from the corresponding TCP socket.
Fix a wrong assertion in:
```
commit 98ec46d726
Author: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Tue Jul 20 09:10:43 2021 +0900
tcp_send_buffered.c: fix iob allocation deadlock
Ensure to put the wrb back onto the write_q when blocking
on iob allocation. Otherwise, it can deadlock with other
threads doing the same thing.
```
I forget to submit this with https://github.com/apache/incubator-nuttx/pull/4257
With an applictation using mbedtls, I observed retransmitted segments
with corrupted user data, detected by the peer tls during mac processing.
Looking at the packet dump, I suspect that a wrb which has been put back
onto the write_q for retransmission was partially sent but fully acked.
Note: it's normal for a retransmission to be acked before sent.
In that case, the bug fixed in this commit would cause the wrb have
a wrong sequence number, possibly the same as the next wrb. It matches
what I saw in the packet dump. That is, the broken segments contain the
payload identical to one of the previous segment.
Consider a bi-directional TCP connection:
1. we use all IOBs for tx queue
2. we advertize zero recv window because we have no free IOBs
3. if the peer tcp does the same thing,
both sides advertize zero window and can not drain the tx queue.
For a similar stall to happen, the peer doesn't need to be
a naive tcp implementation like nuttx. A naive application blocking
on send() without draining its read buffer is enough.
(Probably such an application should be fixed to drain rx even
when tx is full. However, it's another story.)
This commit avoids the situation by prevent tx from grabbing
the all IOBs in the first place. (assuming CONFIG_IOB_THROTTLE > 0)
Gregory Nutt is the copyright holder for those files and he has submitted the
SGA as a result we can migrate the licenses to Apache.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
My recent changes to buffered tcp send broke this. [1]
One of my local apps using non-blocking tcp is working
again with this fix.
[1]
```
commit 837e1a72a4
Author: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Mon Mar 15 16:19:42 2021 +0900
tcp_send_buffered.c: improve tcp write buffering
```
Summary:
- Based on the discussion (PR#2772), let me revert the commit
Impact:
- None
Testing:
- N/A
This reverts commit ec8bf5c8c1.
Suggested-by: YAMAMOTO Takashi <yamamoto@midokura.com>
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
Summary:
- This commit adds DEBUGASSERT() to check the IOB size
Impact:
- None
Testing:
- Tested with sabre-6quad:netnsh with QEMU
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
RFC2001: TCP Slow Start, Congestion Avoidance, Fast Retransmit,
and Fast Recovery Algorithms
...
3. Fast Retransmit
Modifications to the congestion avoidance algorithm were proposed in
1990 [3]. Before describing the change, realize that TCP may
generate an immediate acknowledgment (a duplicate ACK) when an out-
of-order segment is received (Section 4.2.2.21 of [1], with a note
that one reason for doing so was for the experimental fast-
retransmit algorithm). This duplicate ACK should not be delayed.
The purpose of this duplicate ACK is to let the other end know that a
segment was received out of order, and to tell it what sequence
number is expected.
Since TCP does not know whether a duplicate ACK is caused by a lost
segment or just a reordering of segments, it waits for a small number
of duplicate ACKs to be received. It is assumed that if there is
just a reordering of the segments, there will be only one or two
duplicate ACKs before the reordered segment is processed, which will
then generate a new ACK. If three or more duplicate ACKs are
received in a row, it is a strong indication that a segment has been
lost. TCP then performs a retransmission of what appears to be the
missing segment, without waiting for a retransmission timer to
expire.
Change-Id: Ie2cbcecab507c3d831f74390a6a85e0c5c8e0652
Signed-off-by: chao.an <anchao@xiaomi.com>
remove the connection assertion since the instance will be invalid
if the network device has been taken down.
net/netdev/netdev_ioctl.c:
1847 void netdev_ifdown(FAR struct net_driver_s *dev)
1848 {
...
1871 /* Notify clients that the network has been taken down */
1872
1873 devif_dev_event(dev, NULL, NETDEV_DOWN);
...
1883 }
Change-Id: I492b97b5ebe035ea67bbdd7ed635cb13d085e89c
Signed-off-by: chao.an <anchao@xiaomi.com>
In the current net stack implementation, there is no mechanism
for notifying the loss of the wireless connection, if the network
is disconnected then application sends data packets through tcp,
the tcp_timer will keep retrying fetch the ack for awhile, the
connection status will not be able to be switched timely.
Change-Id: I84d1121527edafc6ee6ad56ba164838694e7e11c
Signed-off-by: chao.an <anchao@xiaomi.com>
