bin/81611: natd runs with -same_ports by default

[Alexander Melkov]

>Number:         81611
>Category:       bin
>Synopsis:       natd runs with -same_ports by default
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun May 29 02:00:09 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Alexander Melkov
>Release:        5.4-STABLE
>Organization:
>Environment:
FreeBSD melkov.ru 5.4-STABLE FreeBSD 5.4-STABLE #4: Sun May 29 03:46:03 MSD 2005     spamtrap at melkov.ru:/usr/obj/usr/src/sys/MELKOV  i386
>Description:
even without -same_ports | -m switch natd tries to allocate the same
source port as in the original packet.

PKT_ALIAS_SAME_PORTS flag is set up in LibAliasInit function, -m switch
can also only set this flag.

Probably this default behaviour is actually good, and that's the manpage
should be shanged, not libalias :).

>How-To-Repeat:
run natd without -m and inspect incoming and outgoing packet ports with tcpdump.

>Fix:
Workaround: create and use a config have with
same_ports no

>Release-Note:
>Audit-Trail:
>Unformatted: