need help with pf configuration

[Nikos Vassiliadis]

On 10/9/2011 10:39 AM, Victor Sudakov wrote:
> Patrick Lamaiziere wrote:
>>
>>> I have a configuration with 2 inside interfaces, 1 outside and 1 dmz
>>> interface. The traffic should be able to flow
>>>
>>> 1) from inside1 to any (and back)
>>> 2) from inside2 to any (and back)
>>> 3) from dmz to outside only (and back).
>>>
>>> I need no details, just a general hint how to setup such security
>>> levels, preferably independent of actual IP addressses behind the
>>> interfaces (a :network macro is not always sufficient).
>>
>> You may use urpf-failed instead :network
>> urpf-failed: Any source address that fails a unicast reverse path
>> forwarding (URPF) check, i.e. packets coming in on an interface other
>> than that which holds the route back to the packet's source address.
>
> Excuse me, I do not see how this is relevant to my question (allowing
> traffic to be initiated from a more secure interface to a less secure
> interface and not vice versa).
>

What if you combine macros and lists?
The ruleset below seems "scalable" to any number of interfaces.

inside1 = em1
inside2 = em2
dmz = em0
insides = "{" $inside1:network $inside2:network "}"

pass in on $dmz from $dmz:network to any
block in on $dmz from any to $insides

This expands nicely to:
lab# pfctl -vf te
inside1 = "em1"
inside2 = "em2"
dmz = "em0"
insides = "{ em1:network em2:network }"
pass in on em0 inet from 192.168.73.0/24 to any flags S/SA keep state
block drop in on em0 inet from any to 10.0.0.0/29
block drop in on em0 inet from any to 192.168.56.0/24

HTH, Nikos