1// Test that SYN-ACK with ACE flags and without 2// ACE flags got dropped. Although we disable ECN, 3// we shouldn't consider this as blackholed as 4// these are dropped due to congestion 5 6`./defaults.sh 7sysctl -q net.ipv4.tcp_ecn=3 8sysctl -q net.ipv4.tcp_ecn_option=2 9` 10 11+0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 12+0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 13+0 bind(3, ..., ...) = 0 14+0 listen(3, 1) = 0 15 16+0 < [ect0] SEWA 0:0(0) win 32792 <mss 1460,nop,nop,sackOK,nop,wscale 8> 17+.002 > [noecn] SA. 0:0(0) ack 1 <mss 1460,ECN e1b 1 ceb 0 e0b 1,nop,nop,nop,sackOK,nop,wscale 8> 18 19// Retransmit SYN 20+0.1 < [noecn] S 0:0(0) win 32792 <mss 1460,nop,nop,sackOK,nop,wscale 8> 21+.002 > [noecn] SW. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> 22 23+0.1 < [noecn] W. 1:1(0) ack 1 win 320 <ECN e0b 1 ceb 0 e1b 1,nop> 24+.002 accept(3, ..., ...) = 4 25 26// Write with AccECN option but with ip-noecn since we received one SYN with ACE=0 27+0.01 write(4, ..., 100) = 100 28+.002 > [noecn] P5. 1:101(100) ack 1 <ECN e1b 1 ceb 0 e0b 1,nop> 29