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CoRD vs. temporary client licenses

Thu, 2007.11.08 - 03:37 — müzso
The CoRD utility (based on the famous rdesktop project) allows Mac OS X users to connect to Windows machines via the Remote Desktop Protocol (RDP) aka. Terminal Services. Unfortunately if the Windows server is a terminal server running in application server mode, then it'll require a TSCAL (Terminal Service Client Access License) from the client. If the client does not provide a valid license, then the server creates a temporary license that is valid for approx. 90 days. This temporary license is based on the so called hardware id that the client sends to the server during the licensing handshake. By default the hardware id is generated from the hostname of the client machine, thus once the temporary license expires, you cannot connect to the TS server anymore. However if you use something else (eg. a random string) as the seed of the hardware id, then a new temporary license is generated on the server every time you connect, providing virtually an unlimited temporary license. As I already wrote, rdesktop has a command line option that you can use to specify the seed (aka. the client hostname) for the license handshake. Unfortunately CoRD does not yet implement this, it takes the same hostname every time. Sad I'm not sure whether it takes the client's hostname or the server's hostname ... in the code I just saw that it takes the hostname from the RDP connection's struct.

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Sat, 2008.06.28 - 19:46 — müzso

CoRD with client hostname support

I've created a modded version of the current CoRD: added a client hostname textbox where you can define an arbitrary value (up to 64 chars) that will be used by the server to issue a temporary TS license for your client. So if you start getting errors about expired temporary TS license, just change the client hostname. The modded version is available here.

Fri, 2009.10.16 - 16:28 — Anonymous (not verified)

Update for snow leopard?

I was using your build of CoRD because of the temp. license issue at one of my clients. I had to upgrade due because it didn't work with Snow Leopard...have you, by any chance, done an updated build with this modification based on the 0.5.1 code base?

Fri, 2009.10.16 - 17:03 — müzso

Re: Update for snow leopard?

No, I've not. Nowadays I use NX Client to log on to our company's Ubuntu based servers (running FreeNX, a free version of NoMachine's NX server), thus CoRD has lost priority for me. But the good news is that the functionality is among the feature-requests for CoRD v0.6. Smile I've already been contacted by somebody (don't remember the name, but it was somebody involved with the CoRD development project) about the details of my patch (how it works and what is it good for). Since it's a very tiny mod, I'm quite positive about the chances of getting it into the next release.