PHP encrypt and decrypt string to be url friendly

Question

I am trying to figure out a way to encrypt a user id number. My idea is to encrypt the id ( between 1 and 5 characters ) in combination with some letters ( like _wordtouse ). The only two requirements are

1. The crypted version can only contain a maximum of 15 characters
2. I need to be able to decrypt the string on a different page

The reason for all of this is that i am trying to "hide" user id numbers when someone enters a users profile. So i am trying to find a way to deliver an encrypted version of the user id through the url as a get parameter.

Does anyone have an idea on how to solve this?

Solution 1

https://stackoverflow.com/a/30189841/1325575 explains this in-depth.

However, the short version, which requires no 3rd party installs:

1. Use openssl_encrypt for encryption
2. Use openssl_decrypt for decryption

I'm confident that with those 3 links you're gonna find what you're after.

Solution 2

I would suggest just using the hashids library which is pretty popular and what many url shortening services use. While it isn't really "encryption", it is likely good enough to hide a user's id number in a url. Example:

$userID = 1234;
$hashids = new Hashids\Hashids('some random secret string');

//encode the user id
$encodedID = $hashids->encode($user_id);

//on the other page, decode the user id
$decodedID = $hashids->decode($encodedID);

Comments

[John Conde]

At Stack Overflow you are expected to try to write the code yourself. After doing more research if you have a problem you can post what you've tried with a clear explanation of what isn't working and providing a Minimal, Complete, and Verifiable example. I suggest reading How to Ask a good question and the perfect question. Also, be sure to take the tour and read this.

[Machavity]

If the question has been answered elsewhere you should delete your answer and flag it as a duplicate

[Machavity]

If the question has been answered elsewhere you should delete your answer and flag it as a duplicate

[lloiacono]

@Machavity, the previous answer advices to use mcrypt which is abandoned, that is why I added which alternatives to use IMO

[Dennis]

@Nino Thank you very much.

[The Onin]

Seems cool, a sample would be nice tho.

[Jonathan Kuhn]

@NinoŠkopac I did include an example in the answer. There is also quite a lot more information on their own website which I linked to.

[The Onin]

I'm sorry, I meant an example of the output.

[Anas Naim]

I used hashids library in 2 large projects, it's an amazing library!