Hi, all:
I have a question about line 1765 to 1776 in tcp_input():
/*
* If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN
* flag is on (half-synchronized state), then queue data for
* later processing; else drop segment and return.
*/
if ((thflags & TH_ACK) == 0) {
if (tp->t_state == TCPS_SYN_RECEIVED ||
(tp->t_flags & TF_NEEDSYN))
goto step6;
else
goto drop;
}
My question is: if we are currently in TCPS_SYN_RECEIVED state, why does
a segment without ACK bother? Why we need to store the segment and
process it? Without considering T/TCP, the code should be:
if ((thflags & TH_ACK) == 0) {
goto drop;
}
Best regards,
blue
_______________________________________________
freebsd-net@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-net
To unsubscribe, send any mail to "[EMAIL PROTECTED]"