Re: When GET = POST?

At 1037065312s since epoch (11/11/02 20:41:52 -0500 UTC), Jeff Dafoe wrote:
> I am glad someone else feels the way I do about this issue. In the case

Perhaps. While I'll admit it's anal-retentive to check the method, I usually do it for important things. Why? Because it adds that extra layer of protection. It's easy to check the method; why not use the functionality if it's available?

Most browsers will warn about the dangers of resubmitting POST data; this can be helpful as additionally reinforcment for users (for example, when submitting a credit card order). Sure, the data aren't any safer, but maybe (just maybe) the *operations* on those data are.

GET means GET; it's not supposed to perform irreversable operations. If you have a delete CGI like this:

http://hackme.example.com/cgi-bin/deleteUser.pl?userId=jbogus

And somebody sneaks that link into an image URL on an oft-visited bulletin board, then your app may perform a valid operation that the user didn't want. *your* app may be safe against XSS, but somebody else's might not be.

Yes, you can sucker a user into performing a POST as well, but it's more difficult (need more HTML, and probably scripting to do it without the user noticing).

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Again, it's not the biggest deal in web programming, but I would consider it a best-practice kind of an issue. It's easy to check, so why not do it?

Jason

-- 
Jason Healy
http://www.logn.net/