Openssl decryption ( DES ) returns false in PHP

Question

I'm trying to decrypt data with DES-ECB encryption, but the response is always false.

When I decrypt the string through https://www.tools4noobs.com/online_tools/decrypt/ the response is correct. This website is using the function "mcrypt_encrypt()" in PHP, but this functionality is not available on my server.

The code that i'm working on should work on PHP 7.1+ version, so the mcrypt_encrypt() isn't available anymore in my system.

$password         = 'password'; // Example
$decryptedString  = 'ThisShouldBeAnTestToCheckIfTheStringIsCorrectDecryptedThroughDES-ECB'; 

// Encrypted the string through the online tool.
$encryptedString  = 'zOToWEkYOoDnNWZ/sWEgOQQAX97NTZami/3V18yeKmoKiuam3DL0+Pu/LIuvjJ52zbfEx/+6WR4JcCjIBojv0H1eYCDUwY3o';

$opensslDecrypt   = openssl_decrypt(base64_decode($encryptedString),'DES-ECB', $password);

var_dump($opensslDecrypt); // Returns false.

I also tried to decrypt without the base64_decode function, but its still returning false.

Anyone have any idea why this isn't decrypting as it should be?

olibiaz · Accepted Answer · 2019-03-26 14:24:17Z

You must precise the $options in you method call:

Just add the following parameter after your password: OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING , ''

<?php

$password         = 'password';
$decryptedString  = 
'ThisShouldBeAnTestToCheckIfTheStringIsCorrectDecryptedThroughDES-ECB'; 

// Encrypted the string through the online tool.
$encryptedString  =  'zOToWEkYOoDnNWZ/sWEgOQQAX97NTZami/3V18yeKmoKiuam3DL0+Pu/LIuvjJ52zbfEx/+6WR4JcCjIBojv0H1eYCDUwY3o';

$opensslDecrypt   = openssl_decrypt(base64_decode($encryptedString),'DES-ECB', $password, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING , '');

var_dump(trim($opensslDecrypt));

Output: string(68) "ThisShouldBeAnTestToCheckIfTheStringIsCorrectDecryptedThroughDES-ECB"

For more information about this options:

What does OPENSSL_RAW_DATA do?

$options as (as for 2016) two possible values OPENSSL_RAW_DATA and OPENSSL_ZERO_PADDING. Setting both can be done by OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING. If no OPENSSL_ZERO_PADDING is specify, default pading of PKCS#7 will be done as it's been observe by [openssl at mailismagic dot com]'s coment in openssl_encrypt()

https://www.php.net/manual/en/function.openssl-decrypt.php

So if i want the string to be converted without base64_decode then is should use the function like this right? $opensslDecrypt = openssl_decrypt($hash, 'DES-ECB', $password, OPENSSL_ZERO_PADDING , '');

Collectives™ on Stack Overflow

Openssl decryption ( DES ) returns false in PHP

1 Answer 1

2 Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Linked

Related