Codeing a firewall C#

Saviour_Angel

Hey,

At present I'm in college and am designing a firewall for my year’s project.
I'm coding it in C# using XML for storing settings...

The lecturers in my college have said that this type project has never been done before for them so there's little info I can get out of them.

I've searched many sites looking for information on how to detect network activity, packets, and sockets being used.
From the sites I've got the info is useful but it's vague, I was wondering if anyone has any sites that they might be willing to share in relation to helping me with my little problem.
Or even that ye may have classes or snippets of code to help me on my way.

Anything at all would be a great help...:)

("The great thing about a project like this is that I've practicaly got admin rights on the network")

Smoggy

http://www.pscode.com/vb/scripts/ShowCode.asp?txtCodeId=4474&lngWId=10

Might get you going.

ressem

Nah, the previous thing is just a wrapper arround the netstat command.

This might work better to introduce the topic.
http://www.codeproject.com/internet/drvfltip.asp
http://www.codeproject.com/internet/FwHookDrv.asp

However, if you need to take the kernel mode driver route, it's difficult to see how you're going to approach it in c#. A lot of this stuff is in c, not even c++. I'd think that you'd need a lot of unmanaged code elements.

Alternatives include NDIS Intermediate level drivers, samples of which are included in the windows DDK.
Or using the Vista windows filtering platform methods if you want to risk stuff that isn't even released yet.
http://www.microsoft.com/whdc/device/network/WFP.mspx
http://windowssdk.msdn.microsoft.com/en-us/library/ms688974(vs.80).aspx

Saviour_Angel

Cool, thanks guys...
I'll read these latter, thanks for the help...

ressem

This appears to be as close as you'll get to a .net firewall that I can see.
http://www.codeproject.com/managedcpp/packetfilteringnet.asp

declan_lgs

Cool. I always wanted to make a firewall - I haven't found one decent free (as in freedom ) one for Windows (where a firewall is most useful).

What kinda functionality will you be going for? Will you be releasing the code?

Saviour_Angel

Ya I'll release the source code when I'm finished and yes it's for windows OS with the .net framework 2 liabriarys.
Altho I have no idea how or were I should publish it..

I'm makeing it so that I can block applications at port level, inc IP Address...
All my work will be fully documented for anyone wanting to know what I did... As per what is needed for a college project..

Any way it dosn't matter for now as I won't have this finished till the end of this year / start of the new year...

declan_lgs

nice.

Saviour_Angel wrote:

Ya I'll release the source code when I'm finished and yes it's for windows OS with the .net framework 2 liabriarys.
Altho I have no idea how or were I should publish it..

Savannah or Sourceforge?