python for windows internet filter / firewall

[thorley]

Greetings,

I'm interested in a simple content-based internet firewall/filter,
similar to dansguardian (http://dansguardian.org/), but written in
python, and for windows. I assumed such a project would already exist,
but my searches on freshmeat, and google turned up empty. I would be
interested in starting my own project if necessary, so I have two
questions:

1) Does any one no of such a project?

2) Is this even reasonable in python and how might I get started? (e.g.
win32 COM?)

Thanks much
--
matthew

[Diez B. Roggisch]

> 2) Is this even reasonable in python and how might I get started? (e.g.

win32 COM?)

Don't know much (not to say nothing) about windows firewalling & the
interfaces one needs to talk to them.

But _what_ I know is: a firewall needs to be fast. The big guys in
networking put a lot of effort into pushing as much package processing as
possible into the hardware-layer.

And as much as I love python - I do not see it here, beyond a
proof-of-concept.

Diez

[thorley]

I thought speed might be an issue. At this point I'm not interested in
much more than toying around, so *if* there's a way to do it, I'd like
to explore the options.

--
matthew

Diez B. Roggisch wrote:

2) Is this even reasonable in python and how might I get started? (e.g.
win32 COM?)

Don't know much (not to say nothing) about windows firewalling & the
interfaces one needs to talk to them.

But _what_ I know is: a firewall needs to be fast. The big guys in
networking put a lot of effort into pushing as much package processing as
possible into the hardware-layer.

And as much as I love python - I do not see it here, beyond a
proof-of-concept.

Diez

[Michele Petrazzo]

th*****@gmail.com wrote:

Greetings,

I'm interested in a simple content-based internet firewall/filter,
similar to dansguardian (http://dansguardian.org/),
Firewall and filter are two things totally separated!

- If you want to do something like a "page filtering", like dansguard
and squidguard, you can simple do it with python, because you have to
act like a proxy that leave of not visit a page.
- If you have to do a firewall... I think you can't, especially if you
are on win. Take a look at wipfw (wipfw.sf.net) that do what you want
but written in python,
Of course :)

and for windows.

Why? All that work with networking (and not only that) work better with
*nix OS!
I assumed such a project would already exist,
Firewall I don't think, and the same for the filtering (I know only
something like a plugin for squid, so for *nix platform).
but my searches on freshmeat, and google turned up empty. I would be
interested in starting my own project if necessary, so I have two
questions:

1) Does any one no of such a project?

2) Is this even reasonable in python and how might I get started?
(e.g. win32 COM?)
win32COM for do what?

You can do it in not so difficult manner:
Take twisted and its proxy class, make some outline code (for filter the
pages) and enjoy! (work also on win)

Thanks much -- matthew

P.s. Don't forgot to share your code, when it'll work :)

Bye,
Michele

[thorley]

Thanks for a detailed reply.

Firewall and filter are two things totally separated!
Sorry for being to general. I want to create a filter like
dansgaurdian. I was thinking of it also as a firewall because is
restricts traffic on a port based on content, but you're correct, they
aren't the same thing at all.
Take a look at wipfw (wipfw.sf.net) that do what you want
Thanks for the tip I'll check it out.
And for windows. Why? All that work with networking (and not only that) work better with
*nix OS!
Yes you are correct again. I am infact working on linux right now, and
it is my os of choice. How ever I need to deploy this on M$win :(
win32COM for do what?
My knowledge of COM is miniscule, but I assumed it has a low level
interface for packet filtering.
You can do it in not so difficult manner:
Take twisted and its proxy class, make some outline code (for filter the
pages) and enjoy! (work also on win)

Proxy would be an easy way, but I wanted to do it at a lower level.

Thanks again.
--matthew

[Michele Petrazzo]

th*****@gmail.com wrote:

Thanks for a detailed reply.

I thing that now we are becoming OT... :)
because is restricts traffic on a port based on content, but you're
correct, they aren't the same thing at all.

So, what you want to do? Open and close a destination IP (domain),
following what the user see, with a firewall? It's so hard to do, and it
doesnt' sound like a good think. This is the work of a proxy, not of a
firewall.

win32COM for do what?

My knowledge of COM is miniscule, but I assumed it has a low level
interface for packet filtering.

Yes, but you have to create a dll that work at low level and has an low
level features... Something like that wipfw do: create a .sys/.vxd (if I
remember correctly) that in your case are the dll and after with an exe
(that are the python program) that teach the rules... Very bas idea, for me!

You can do it in not so difficult manner: Take twisted and its
proxy class, make some outline code (for filter the pages) and
enjoy! (work also on win)

Proxy would be an easy way, but I wanted to do it at a lower level.

But you _can't_ with python. How you create a .sys/.vxd file? Also that
has only few kb program? And don't such more than few kb memory?

Keep the proxy way or switch to another language :)
Thanks again. --matthew

Michele