RDR with sourceroute?

This could potentially be an embarrassing question, but I'm trying to get my
head around something. Incoming "rdr" rules (with rr) is currently working fine,
assuming the machines in the internal network uses the IPFilter box as their
default gateway.

However, with the L4 hardware devices we can do the same, but ask it to relay
the packet as-if it came from the L4 device. Which is what NAT does.

Can I do this with IPFilter? There seems to be no option for it with "rdr"
rules, so I was trying out various NAT rules for it, along the lines of:

map wm0 from any to extIP/32 port = 5353 -> 172.16.5.220/32 portmap tcp 5353:5353

But it is clearly invalid to specify the rhs like so (IP that isn't "ours", and
a port range of just one port?).

What am I missing though? Can it be done?

Lund

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Jorgen Lundman | <lundman@lundman.net>
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