Securing my app & obfuscation ...

[illskills]

ok so i've spent the last five years of my free time developing an application I believe I almost have ready for deployment.

I have added code to enable a 30 day demo. (all export functions are disabled)

The code encrypts a date to the registry.

This is then decoded and checked by the software on load.


If they back date the computer to extend the demo beyond 30 days it will quit.
If the date expires it quits the user / and asks for a reg key.

The key is generated from the machines ID code.

and stored in the reg encrypted when the app is registered.

My question is this ... do i need to include any extra security checks ... is this the best way of securing my software.

and ... obfuscation ... should i obfuscate my code.

and can someone point me to a good freeware obfuscator b/c i've looked throught the first 30 pages of google results all the ones i can find are demo versions and will not let me obfuscate the code and most are really expensive.

thanks for your help in advance
John

i have also searched these forums but most links to obfuscators / security tutorials

[gep13]

Hey,

Regarding obfuscation, you might want to take a look at the following blog post:

http://blogs.msdn.com/clrsecurity/ar...26/422440.aspx

Bottom line, if you want a "good" obfuscation tool, you typically need to go third party, which means shelling out some money.

Gary

[illskills]

going to check this out

[gep13]

Hey,

Let me know how you get on, and if you have any other questions.

Gary

[illskills]

i think the best solution to this problem is ...

to release the first version of my software ... then save to buy the professional version of MSVS which comes with a very good obfuscator as standard

.... i had a look @ obfuscar but the installation guide is none existent, there is a sample project included but i havnt had chance to check it yet.

i believe my application is vunerable to hackers atm b/c the security is basic this is the first time i've had to program something like this by myself.

do you have any suggestions for hiding a registry key ?
and any advise on creating a secure app is appreciated.

thanks for your previous post

[gep13]

Hey,

What exactly does your app do? The question that springs to mind immediately is, does it require to be secure?

Gary

[illskills]

its a desktop app ... i've restricted certain features on the demo version ... this provides a serial number based on the machines id then i have a keygen to create the license keys on my machine ... when registered the key is stored in the registry encrypted ... i want to try my best to stop hackers making a keygen for the app or decompiling

and also stop competitors stealing my source & classes

(its a design app aimed @ the tile industry)