Jul 162014

XViewer logoIn my [last post] I have talked about the older TRENDnet TK-IP101 KVM-over-IP box I got to manage my server over the network even in conditions where the server itself is no longer reachable (kernel crash, BIOS, etc.).

I also stated that the client software to access the box is in a rather desolate state, which led me to the extreme step of decompiling the Java-based Viewer developed by TRENDnet called KViewer.jar and its companion tool for SSL certificate imports, Impcert.jar.

Usually, software decompilation is a rather shady business, but I did this as a TRENDnet support representative could not help me out any further. After reverse-engineering the software, making it compatible with modern Java Runtime environments and fixing a blocker bug in the crypto code, I sent my code and the binary back to TRENDnet for evaluation, asking them to publish the fixed versions. They refused, stating that the product was end-of-life.

In a second attempt, I asked the guy for permission to release my version of KViewer including the source code and also asked which license I could use (GPL? BSD? MIT?). To my enormous surprise, the support representative conferred with the persons in charge, and told me that it had been decided to grant me permission to release KViewer under the GNU General Public License (GPL), as long as all mention of TRENDnet and related products are removed from the source code and program.

To further distinct the new program from its original, I renamed it to “XViewer”, and its companion tool to “XImpcert”, as a hommage to my server, XIN.at.

KVM host:port

The former KViewer by TRENDnet, that works up to Java 1.6u27


XViewer, usable on JRE 1.7 and 1.8

Now, I am no Java developer, I don’t know ANYthing about Java, but what I did manage to do is to fix all errors and warnings currently reported by the Eclipse Luna development environment and the Java Development Kit 1.7u60 on the source code. While my version no longer supports Java 1.6, it does run fine on Java 1.7u60 and 1.8u5, tested on Windows XP Professional x64 Edition and CentOS 6.5 Linux x86_64. A Window closing bug has been fixed by my friend Cosmonate, and I myself got rid of a few more. In addition to that, new buttons have been added for an embedded “About” window and an embedded GPLv3 license as suggested by TRENDnet.

On top of that, I hereby state that I am not affiliated with TRENDnet and that TRENDnet of course cannot be held liable for any damage or any problems resulting from the use of the modified Java viewer now known as XViewer or its companion tool XImpcert. That shall be said even before the release, as suggested to TRENDnet by myself and subsequently confirmed to be a statement required by the company.

In the very near future, I will create a dedicated site about XViewer on this weblog, maybe tomorrow or the day after tomorrow.

Oh and of course: Thanks fly out to Albert from TRENDnet and the people there who decided to grant me permission to re-release their viewer under the GPL! This is not something that we can usually take for granted, so kudos to TRENDnet for that one!