Re: [Qemu-devel] Anyone familiar with the slirp code?

[John R. Hogerhuis]

I don't think the original author anticipated or cared about slirp being
ported to a 64-bit processor. I won't speak for the quality of the code
in general, but on a 32-bit machine the pointer size is 32-bit. It's
perfectly safe on that platform to use any 32-bit spot as a hidey hole
for your cookies.

Things like this is why porting from 32-bit to 64-bit is hard. Frankly I
wonder at the reason for increasingly higher word sizes on machines. Is
the bulk of our data these days really 64-bits long? But I digress...

Just go for it. The slirp code was imported into qemu. At this point
you're probably as much an expert as anyone. There is no upstream
maintainer for the code either, I looked and found and asked the last
sucker that had maintained it for a bit, and he just wanted to unload
it.

If you fix it though, be prepared for the fact that you will be the new
expert ;-)

One thing I'd like to see long term is to completely remove the NAT code
and replace it with something more modern and robust like netfilter.
That would give us a lot of nice application level gateways (nat
modules) for important protocols, and some tweakable firewall settings
for user-net.

While I'm wishing, in fact it would be a nice feature in general for
QEMU to have a built in firewall pointed at each host with fairly
minimal permissions by default. A windows machine on your network is a
windows machine on your network, virtual or not :-)

-- John.