Confused by pptp and gre, what is the true way to do it?

Gabriele Bulfon <[email protected]> Wed, 10 Nov 2010 17:02:22 +0100 (CET)
Newsgroups gmane.comp.security.firewalls.ipfilter
Message-ID <29715_1289405372_4CDAC3BC_29715_5964_1_3385016.283.1289404942003.JavaMail.root@www>
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Hello, I've read around about how to make windows pptp vpn work behind ipfilter, but I've seen
a lot of confusion...(to me, at least).
My windows machine is in the LAN, passing through a solaris machine with ipfilter 4.1.9.
What are the general rules to let Windows pass the NAT and run the handshake?
Some talks about proxy / pptp rules mappings, some talks about just opening the ports...
I tried this but it doesn't work:
ipnat:
#NAT rules
map igb1 mylan/24 -mypubip/32 proxy port ftp ftp/tcp
map igb1 mylan/24 -mypubip/32 portmap tcp/udp 10000:40000
map igb1 mylan/24 -mypubip/32
#redirect gre to my windows machine
rdr igb1 mypubip/32 -winlanip gre
ipf:
#NAT windows machine
pass out quick on igb1 from mywinip/32 to any keep state
#Let gre enter the firewall
pass in quick on igb1 proto gre from any to mypubip/32
#Let gre pass the rdr
pass in quick on igb1 proto gre from any to winlanip/32
-= Mail sent through WebTop2 =-

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<div style=3D"font-family: Verdana; font-size: 12px;">Hello, I&#39;ve read =
around about how to make windows pptp vpn work behind ipfilter, but I&#39;v=
e seen<br>a lot of confusion...(to me, at least).<br><br>My windows machine=
 is in the LAN, passing through a solaris machine with ipfilter 4.1.9.<br>W=
hat are the general rules to let Windows pass the NAT and run the handshake=
?<br>Some talks about proxy / pptp rules mappings, some talks about just op=
ening the ports...<br><br>I tried this but it doesn&#39;t work:<br><br>ipna=
t:<br><br>#NAT rules<br>map igb1 mylan/24 -&gt; mypubip/32 proxy port ftp f=
tp/tcp<br>map igb1 mylan/24 -&gt; mypubip/32 portmap tcp/udp 10000:40000<br=
>map igb1 mylan/24 -&gt; mypubip/32<br>#redirect gre to my windows machine<=
br>rdr igb1 mypubip/32 -&gt; winlanip gre<br><br>ipf:<br>#NAT windows machi=
ne<br>pass out quick on igb1 from mywinip/32 to any keep state<br>#Let gre =
enter the firewall<br>pass in quick on igb1 proto gre from any to mypubip/3=
2<br>#Let gre pass the rdr<br>pass in quick on igb1 proto gre from any to w=
inlanip/32<br><div><br><font size=3D"1">                 -=3D Mail sent thr=
ough WebTop2 =3D-</font>
</div></div>

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