xref: /linux/tools/testing/selftests/net/packetdrill/tcp_tcp_info_tcp-info-rwnd-limited.pkt (revision 0ad9617c78acbc71373fb341a6f75d4012b01d69)
1// SPDX-License-Identifier: GPL-2.0
2// Test rwnd limited time in tcp_info for client side.
3
4`./defaults.sh`
5
6// Create a socket and set it to non-blocking.
7    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
8   +0 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR)
9   +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0
10
11   +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress)
12   +0 > S 0:0(0) <mss 1460,sackOK,TS val 100 ecr 0,nop,wscale 8>
13
14// Server advertises 0 receive window.
15 +.01 < S. 0:0(0) ack 1 win 0 <mss 1000,nop,nop,sackOK>
16
17   +0 > . 1:1(0) ack 1
18   +0 getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
19   +0 fcntl(3, F_SETFL, O_RDWR) = 0   // set back to blocking
20
21// Make sure that initial rwnd limited time is 0.
22   +0 %{ assert tcpi_rwnd_limited == 0, tcpi_rwnd_limited }%
23
24// Receive window limited time starts here.
25   +0 write(3, ..., 1000) = 1000
26
27// Check that rwnd limited time in tcp_info is around 0.1s.
28  +.1 %{ assert 98000 <= tcpi_rwnd_limited <= 110000, tcpi_rwnd_limited }%
29
30// Server opens the receive window.
31  +.1 < . 1:1(0) ack 1 win 2000
32
33// Check that rwnd limited time in tcp_info is around 0.2s.
34   +0 %{ assert 198000 <= tcpi_rwnd_limited <= 210000, tcpi_rwnd_limited }%
35
36   +0 > P. 1:1001(1000) ack 1
37
38// Server advertises a very small receive window.
39 +.03 < . 1:1(0) ack 1001 win 10
40
41// Receive window limited time starts again.
42   +0 write(3, ..., 1000) = 1000
43
44// Server opens the receive window again.
45  +.1 < . 1:1(0) ack 1001 win 2000
46// Check that rwnd limited time in tcp_info is around 0.3s
47// and busy time is 0.3 + 0.03 (server opened small window temporarily).
48   +0 %{ assert 298000 <= tcpi_rwnd_limited <= 310000, tcpi_rwnd_limited;\
49         assert 328000 <= tcpi_busy_time <= 340000, tcpi_busy_time;\
50}%
51
52   +0 > P. 1001:2001(1000) ack 1
53 +.02 < . 1:1(0) ack 2001 win 2000
54   +0 %{ assert 348000 <= tcpi_busy_time <= 360000, tcpi_busy_time }%
55