Picking encryption cipher for mcrypt
- by Autolycus
I have few questions about this code:
<?php
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
$key = "This is a very secret key";
$text = file_get_contents('path/to/your/file');
echo strlen($text) . "\n";
$crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_ECB, $iv);
file_put_contents('path/to/your/file', $crypttext);
?>
It encrypts the file just fine, however it adds additional nulls at the end, so if I encrypt:
a test string is this one
and here is a new line
once decrypted becomes:
a test string is this one
and here is a new line 000000000000000
What's going on?
Second, is MCRYPT_RIJNDAEL_256 compatible with AES-128?
Finally, how would I let another party decrypt a file I've encrypted? They would need to know which encryption was used and I am not sure what to tell them.
