> +		/*
> +		 * Calculate the RTT from the returned time stamp and the
> +		 * connection's time base.  If the time stamp is later than
> +		 * the current time, fall back to non-1323 RTT calculation.
> +		 */
> +		now = TCP_TIMESTAMP(tp);
> +		if (SEQ_GT(now, opti.ts_ecr))
> +			opti.ts_ecr = now - opti.ts_ecr + 1;
> +		else
> +			opti.ts_ecr = 0;

- i don't think that it makes much sense because it still allows
  unsafe rtt values.  it's better to be more strict here.
  eg. (now - ts_ecr) < (1 day)
- SEQ_GT is for tcp_seq, not for timestamps.

i think it's better to assert (tvmin <= tvmax) in TCPT_RANGESET.

YAMAMOTO Takashi