Wordpress Symetric (kinda) Encryption

[nacedo]

I am using Formidalbe Pro on my wordpress site.

Users are sending me a form that I make editable by them and by me (Its all managed by Formidable). They have to be logged-in with wordpress to fill the form and edit it. No anonymous access.

I want to encrypt the data they send on the database and I want a way that the data could be decrypted by only me and by the user so it can be modifiable...

What kind of encryption and how could I manage to implement that ?

Here is the Formidable Pro hooks : http://formidablepro.com/knowledgebase/action-hooks/

Thanks !

[nacedo]

To think about it, I dont have to edit/see the information.

I don't know anything about this FP, but you can use a 'key' to encrypt data. As you'll be using secure logins, I'm assuming you'll just need the one key. Have a look at mcrypt: http://us3.php.net/manual/en/mcrypt.examples.php

Be aware that, depending on the encryption that you use, the ciphertext may be of a longer length to the plaintext, in which case you may need to expand the size of certain database fields. Otherwise strings will be truncated and they will not be able to be decrypted - so you end up with a load of junk. Users will not thank you ;)