Online PHP editor | refs for aZmJO

@ 2015-12-15T05:30:22Z

<?php

function getExpectedCiphertextSize(int $sizeOfInput) : int
{
    $padding = ($sizeOfInput % 16);
    if ($padding === 0) { // PKCS7
        $padding += 16;
    }
    return 16 // IV
        + 32 // HMAC-SHA-256
        + $sizeOfInput
        + $padding;
}

var_dump(getExpectedCiphertextSize(100));