If you hash your password and then apply a salt, how should someone crack it with sniffing or whatever? O.O

You don't need to crack it, it essentially became your password. You just need to send it to the server.

By the way, any operation performed on the client can be traced. And let me stress that again, a salt is not a super secret thing no one is allowed to know. It's not there to make a single hash harder to crack, it's there to make it harder to crack all other hashes.

Edit: Also, you apply to the salt to the password and then hash it. Hash once, don't use double hashes or anything weird. That's just decremental to security.

Thank you JustSid and Quadraxas!
Very informative and valuable!
I used my day to do some research on adaptive hash functions respectively bcrypt.
I was really afraid of implementing it, because i look so complicated.
But fortunately bcrypt is already implemented in PHP 5.5!
So i had no problems using it.

Tomorrow i´ll do some research on secure server connection.
I´ll ask here again if i don´t understand something.

Thank you very much again!

Haha fuck ur right O:
YOu can simply send it now to the server ..
I didnt think at this :DD
I should change my login now. :|

And that's the problem with everything cryptography: It's hard to think outside of the box and only making it secure against attacks oneself can think of is not going to actually make it secure.

That's why security through obscurity doesn't work and the advice is always to use a peer reviewed, battle tested public implementation and algorithm. If enough eyes look on it, chances are high it won't blow up immediately. Or put differently: Let other looks at your implementation and let them try to break it.

Hey it´s me again. I´ve got a question.
Do you think that it would make sense to implement captcha?
I don´t think it will since my game is no message board and i can´t imagine what a bot would do after registration.

What would you like to achieve with a captcha? Keeping bots from signing up? If so, what would the problem of that be?
Keep in mind that the bots have to be taught your custom protocol, so someone needs to have an incentive to write such a bot.

If you want to protect yourself against flooding, you should introduce rate limiting into your API endpoints, and define sensible limits (eg. a peer may only request the server list 5 times per minute). That's not a (D)DoS protection, but it can help you avoid heavy computations on the database.

Rate limiting you can do on something like redis, or some other in-memory store. Doesn't need to persistent, if the data is lost all rates are reset, but who cares. The advantage is that you don't need to do the full roundtrip to the full-blown database backend which has to drop down to the disk to ensure integrity.

Last but not least, here is a presentation about Cryptography called Everything you need to know about cryptography in 1 hour. Keep in mind thought that cryptography ins't the same as security.

Edit: Here is the video to the slides: http://blip.tv/fosslc/everything-you-need-to-know-about-cryptography-in-1-hour-3646795

@JustSid
Thanks again for your answer!


I´ve now implemented everything you told me.
Now my Login script should be safe enought for a multiplayer game, isn´t it?

Impossible to tell without reviewing the code.

Would you do it if i share the code with you?