Subject: Re: faith(4) thoughts
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: None <itojun@iijlab.net>
List: tech-net
Date: 07/20/2002 08:30:06
>> err, i don't like tweaking pcb layer for "any port" bind(2) support,
>Is this because you don't think "any port" semantics should be
>available, or because you think this is the wrong place to implement
>them? If the latter, where would you prefer? I can't see any way to
>implement "any port" semantics without affecting the code that matches
>incoming packets to listening sockets, almost by definition.
i don't want "any port" semantics be available on pcb.
>This is one reason I'd like to see address/mask bindings, because it
>would avoid most of the need for faith. (You'd still need _some_ way
>to say "any address matching this <addr,mask> pair is mine", rather
>than the way most interfaces match just one address. Perhaps each ifa
>should have a mask associatd with it? If done right, it could also
>help hosting farms that give each customer host its own address.)
i guess NAT-PT (per-packet translation) is what you want. however,
it has pros and cons:
- faith:
pros: simple to implement, no packet fragmentation issues
(since it is in L4)
cons: per-port
- NAT-PT
pros: any port
cons: fragmentation issue (since it is in L3), complex state
management
i guess it has to be part of ipfilter. as ipfilter is not very
version-independent, my todo list has "NAT-PT on openbsd PF",
but not for ipfilter.
itojun