function aes256EcbPkcs7PaddingEncrypt($key, $data) {
    $padding = 16 - (strlen($data) % 16);
    $data .= str_repeat(chr($padding), $padding);
    return mcrypt_encrypt(MCRYPT_RIJNDAEL_128, hash('SHA256', $key, true), $data, MCRYPT_MODE_ECB);
}

function aes256EcbPkcs7PaddingDecrypt($key, $data) {
    $data = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, hash('SHA256', $key, true), $data, MCRYPT_MODE_ECB);
    $padding = ord($data[strlen($data) - 1]); 
    return substr($data, 0, -$padding); 
}