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// Test that getsockopt of TCP_MAXSEG works on passive/server TCP connections.
// In this variant we test that we get the expected result when
// the routing config specifies an "advmss 1430 mtu lock 1470" for the
// route to the remote IP under test.
// To ensure that we do not cache something that interferes with other tests:
--remote_ip="192.0.2.2"
`ip route change 192.0.2.2 via 192.168.0.2 dev tun0 advmss 1430 mtu lock 1470`
// Set up a listening socket.
0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+0 bind(3, ..., ...) = 0
+0 listen(3, 1) = 0
// Establish a connection without timestamps.
+0 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,nop,wscale 7>
+0 > S. 0:0(0) ack 1 <mss 1430,nop,nop,sackOK,nop,wscale 6>
+0 < . 1:1(0) ack 1 win 257
+0 accept(3, ..., ...) = 4
// Verify that the kernel returns the expected TCP max payload size.
+0 getsockopt(4, SOL_TCP, TCP_MAXSEG, [1430], [4]) = 0
+0 write(4, ..., 1500) = 1500
+0 > . 1:1431(1430) ack 1
+0 > P. 1431:1501(70) ack 1
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