Encrypt string in JavaScript and decrypt in PHP with RSA technique

Question

I am trying to encrypt some text in JavaScript and then send it to PHP (etc: with Ajax) to decrypt it there and save it (etc: In MySQL).

Here is my code so far:

In JavaScript:

I am using this library for the encryption: http://travistidwell.com/blog/2013/02/15/a-better-library-for-javascript-asymmetrical-rsa-encryption/

function ConvertToURL(data) {
    // Converts data to URL friendly form
    // etc: Replaces '+', '/', '=' with 'plus', 'slash', 'equal'
};
function AjaxOrder(data) {
    // Sends data in PHP with Ajax
};

var publicKey = '-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDlOJu6TyygqxfWT7eLtGDwajtN
FOb9I5XRb6khyfD1Yt3YiCgQWMNW649887VGJiGr/L5i2osbl8C9+WJTeucF+S76
xFxdU6jE0NQ+Z+zEdhUTooNRaY5nZiu5PgDB0ED/ZKBUSLKL7eibMxZtMlUDHjm4
gwQco1KRMDSmXSMkDwIDAQAB
-----END PUBLIC KEY-----';

var encrypt = new JSEncrypt();
encrypt.setPublicKey(publicKey);
var encrypted = encrypt.encrypt('Text to send.');

AjaxOrder(ConvertToURL(encrypted));

In PHP:

$dataPost = $_POST('dt');

function ConvertFromURL($data) {
    // Converts $data to original form
    // etc: Replaces 'plus', 'slash', 'equal' with '+', '/', '='
}
function ReturnData($data) {
    // Sends $data back in JavaScript as an answer to Ajax
}

$privateKey = '-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----';

openssl_private_decrypt(ConvertFromURL($dataPost), $decryptedWord, $privateKey);

ReturnData(base64_encode($decryptedWord));

Now the answer from PHP is empty every time. Any ideas to make this work?

Thank you for your time!

Answer 1

Maybe try doing base64_decode in the ConvertFromURL($data) function?

Answer 2

Yes,

It adds some "random" padding tot the message before it does the magic.