//insere a Alice da Base de Dados
$database->insertUserDatabase($username_Alice, $password_Alice, $openSSL_Alice->getCertificateSerialNumber());
//FIM CRIACAO DO USER ALICE
echo "<h4>registou a Alice </h4>";
echo " <h1>PARTE 2 </h1>";
//extrai a chave publica do Bob
$public = $openSSL_Bob->certificate();
echo "<h4>extrai a chave publica do Bob </h4>";
//cria chave AES
$AES_key = bin2hex(openssl_random_pseudo_bytes(12, $cstrong));
echo '<h4>cria chave AES </h4>"' . $AES_key . '"';
//encripta a mensagem com a chave AES
$encrypted_message = $openSSL_Bob->encryptAES256($message, $AES_key);
echo '<h4>encripta a mensagem com a chave AES </h4>"' . $encrypted_message . '"';
//encripta a chave AES com a chave publica do Bob
$encrypted_AES_key = $openSSL_Bob->encrypt($AES_key);
echo '<h4>encripta a chave AES com a chave publica do Bob </h4>"' . $encrypted_AES_key . '"';
//assina a mensagem com chave privada da Alice
$mensagem_assinada = $openSSL_Alice->sign($encrypted_message, $passphrase_Alice);
echo '<h4>assina a mensagem com chave privada da Alice </h4>"' . $mensagem_assinada . '"';
//notifica o bob
$Bob = $database->findUserByCerticateSerialNumber($openSSL_Bob->getCertificateSerialNumber());
$database->insertMessage($FromUser_id, "3", $encrypted_message, $encrypted_AES_key);
echo "<h4>notifica o Bob </h4>";
echo "IMPECAVEL";
// FIM PRIMEIRA PARTE
// SEGUNDA PARTE
//recebe a notificacao
echo " <h1> <br>PARTE 3 </h1>";
echo "<h4>recebe a notificacao </h4>";
echo "<h4>Tem " . $database->checkForNotifications("3") . " mensagens por ler </h4>";
$public = $openSSL->certificate();
print "<h3>Key and Certificate Generation</h3>";
print "<p>Your certificate belongs to:<br />";
$openSSL->getCommonName() . "</p>";
print "<p>Distinguished Name:<br /><pre>";
print_r($openSSL->getDN(), 1) . "</pre></p>";
print "<p>Your private key is:<br /><pre>{$private}</pre></p>";
print "<p>Your public key is:<br /><pre>{$public}</pre></p>";
print "<p>Your certificate is signed by:<br />";
$openSSL->getCACommonName() . "</p>";
print "<p>CA Distinguished Name:<br /><pre>";
print_r($openSSL->getCA(), 1) . "</pre></p>";
print "<hr />";
// encrypt some text using the public key
$text = "The goat is in the red barn.";
$encrypted = $openSSL->encrypt($text);
print "<h3>Ecncryption</h3>";
print "<p>Plain text was:<br />{$text}</p>";
print "<p>And encrypted text is:<br /><pre>{$encrypted}</pre></p>";
// decrypt it using the private key
$decrypted = $openSSL->decrypt($encrypted, $passphrase);
print "<p>Decrypted with Private Key:<br />{$decrypted}</p>";
// sign some message using the private key
$message = "So long, and thanks for all the fish.";
$signed = $openSSL->sign($message, $passphrase);
print "<h3>Signing</h3>";
print "<p>Signed using Private Key:<br /><pre>{$signed}</pre></p>";
// verify signature
$verified = $openSSL->verify($signed);
print "<p>Verifying signature using Certificate:<br />";
if ($verified) {