According to RFC 793, the seqnum test includes 4 cases when STATE >
TCP_SYN_SENT:
Seg-len Recv-win Test
------- -------- ---------------------------------------
0 0 SEG.SEQ = RCV.NXT
0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
>0 0 not acceptable
>0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
or RCV.NXT =< SEG.SEQ+SEG.LEN-1 <RCV.NXT+RCV.WND
After the seq validation, the 'send duplicated ACK' code in FIN_WAIT1/
2/CLOSING/TIMEWAIT state processing is duplicated, so remove them.
Added TEST_CLIENT_SEQ_VALIDATION ztest case in tests/net/tcp.
Signed-off-by: Shrek Wang <inet_eman@outlook.com>
46ba523ba8