NetBSD/dist/ipf/IMPORTANT

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IMPORTANT NOTICE
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1)
If you're using this software and have a rule which ends like this:
flags S
(for TCP), then to make it totally effective, you need to change it to appear
as follows:
flags S/SA
The problem is that the old code would compare all the TCP flags against the
rule (which just has "S") to see if that matched exactly. It is very possible
for this to not be the case and in these cases, the rule would fail to match
a 'valid' TCP SYN packet.
Why does it need to be "S/SA" and not "S/S" ?
"S/S" will match the SYN-ACK as well the SYN.
By defalt, "flags S" will now be converted to "flags S/AUPRFS".
If you have any queries regarding this, see the examples and ipf(4).
If you still have a query or suggestion, please email me.
2)
If a filter rule used, in combination port comparisons and the flags
keywords, a "short" TCP packet, if not explicitly blocked high up in
the list of packets, would actually get matched even though it would
otherwise not have been (due to the ports not). This behaviour has
subsequently been fixed.
3)
If you have BOTH GNU make and the normal make shipped with your system,
DO NOT use the GNU make to build this package.
Darren
darrenr@pobox.com
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