/**
* Initialize by encrypting the given payload.
*
* @param string $payload Payload
* @param KeyManagementAlgorithm $key_algo Key management algorithm
* @param ContentEncryptionAlgorithm $enc_algo Content encryption algorithm
* @param CompressionAlgorithm|null $zip_algo Optional compression algorithm
* @param Header|null $header Optional desired header. Algorithm specific
* parameters are automatically added.
* @param string|null $cek Optional content encryption key. Randomly
* generated if not set.
* @param string|null $iv Optional initialization vector. Randomly generated
* if not set.
* @throws \RuntimeException If encrypt fails
* @return self
*/
public static function encrypt($payload, KeyManagementAlgorithm $key_algo, ContentEncryptionAlgorithm $enc_algo, CompressionAlgorithm $zip_algo = null, Header $header = null, $cek = null, $iv = null)
{
// if header was not given, initialize empty
if (!isset($header)) {
$header = new Header();
}
// generate random CEK
if (!isset($cek)) {
$cek = $key_algo->cekForEncryption($enc_algo->keySize());
}
// generate random IV
if (!isset($iv)) {
$iv = openssl_random_pseudo_bytes($enc_algo->ivSize());
}
// compress
if (isset($zip_algo)) {
$payload = $zip_algo->compress($payload);
$header = $header->withParameters(...$zip_algo->headerParameters());
}
return self::_encryptContent($payload, $cek, $iv, $key_algo, $enc_algo, $header);
}
