My college lab network has three restrictions which really piss me off: it blocks the download of some file types, including some compressed files, it blocks some of the most well known software download sites like tucows and the firewall blocks all ports but port 80 (thus denying regular ftp access to many places). Why? Because the college staff thinks that if we students could download executable files into the lab machines, we could hijack their network and sell it to the russian spamming mafia. Which doesn’t stop the students from downloading whatever they want at home and bring it to the labs via CD’s or pen drives XD
Anyway, sometimes, we fight back. Me, I’ve tried a few homemade proxies, with some degree of success. My latest piece of work is a web service which, given the URL of a file, will download it to the memory of my server and then return the file to the requester as an array of bytes. This breaches both the file type block and the url block since the download is not seen as a proper “file” and the stream is coming from my server, which rests unblocked. It aslo breaches the firewall block since it uses HTTP and SOAP, which naturally go through port 80. So far it’s been 100% functional, and people are using it even from other colleges.
I am quite content with it, but there’s still one point to be covered. Next semester we’re going to get a Linux-oriented lab, and I want to know whether this trick will work there too. I made the web service in .NET - making clients for it in its own framework is a piece of cake, but hell will freeze before I can run them on Linux. Now, since the service communicates with other applications via XML, in theory a JAVA application should be able to consume it while also running in Linux, and I’m quite sure I’ve seen this kind of interop being done before.
However, I’m not sure the service would be functional to a JAVA caller due to the fact that the byte kind is different across frameworks - it ranges from 0 to 255 in .NET, and I’m almost 100% it ranges from -127 to 128 in JAVA. In other words, I fear a JAVA caller will get a corrupted file from my service.
And this is where the volunteer JAVA programmer gets in. All I need is someone who would be so kind as to try and consume it on a JAVA application. If there’s anyone interested, PM me and I’ll give you the address of the service’s wsdl.
And why don’t I try it myself? Well, I’m to lazy to download another framework and then Eclipse or NetBeans (though I do like them a lot).