Best solution to protect PHP code without encryption

php encryption obfuscation
rfgamaral picture rfgamaral · Dec 3, 2008 · Viewed 133.5k times · Source

First of all, I'm not looking for miracle... I know how PHP works and that there's not really way to hide my code from the clients without using encryption. But that comes with the cost of an extension to be installed on the running server.

I'm looking for something different though... I'm not looking to encrypt my code or even obfuscate it. There are many PHP scripts without encrypted/obfuscated code but they are commercial applications. For instance, vBulletin and/or IP.Board forum applications.

I just want to know what approach do these guys use for their applications...

I'm also open to any other suggestions.

Please note that I'm a single person and not working for a company. My product is also very specific, it won't sell that much. I just want you guys to know that I can't afford to consult a legal professional either to sue someone or prepare a commercial license. I'm just looking for a simple way to protect my simple product, if it's indeed possible, somehow...

Answer

Bill Karwin picture Bill Karwin · Dec 3, 2008

Obfuscating things can only inconvenience your legitimate, law-abiding customers, while the people who would would rip you off are not your target paying customers anyway. (edited out other thoughts about obfuscation)

Another suggestion for protecting your software: create a business model in which the code is an incomplete part of the value of your offering. For example, sell product licenses along with access to some data you manage on your site, or license the product on a subscription model or with customer support.

Designing a EULA is a legal matter, not a coding matter. You can start by reading some EULA text for products and websites you use. You might find some interesting details!

Creating a proprietary license is is highly flexible, and probably a subject beyond the intended scope of StackOverflow, since it's not strictly about coding.

Some parts of a EULA that come to mind:

  • Limiting your liability if the product has bugs or causes damage.
  • Spelling out how the customer can use their licensed software, for how long, on how many machines, with or without redistribution rights, etc.
  • Giving you rights to audit their site, so you can enforce the licenses.
  • What happens if they violate the EULA, e.g. they lose their privilege to use your software.

You should consult a legal professional to prepare a commercial EULA.

edit: If this project can't justify the expense of a lawyer, check out these resources:

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