/**
* Gets the shared secret key in BTWOC format. Computes the key if it has not
* been computed already.
*
* @param string $publicKey Public key of the OP
*
* @return BTWOC representation of the number
*/
public function getSharedSecretKey($publicKey)
{
if ($this->sharedKeyComputed == 0) {
$this->cdh->computeSecretKey($publicKey, Crypt_DiffieHellman::BINARY);
$this->sharedKeyComputed = 1;
}
return $this->cdh->getSharedSecretKey(Crypt_DiffieHellman::BTWOC);
}
public function checkHandshake()
{
if ($this->Input->get("useAPIK") == true) {
$this->Database->prepare("UPDATE tl_ctocom_cache %s WHERE uid=?")->set(array("tstamp" => time(), "shared_secret_key" => $GLOBALS['TL_CONFIG']['ctoCom_APIKey']))->execute($this->Input->get("con"));
return true;
} else {
// Imoprt
require_once TL_ROOT . '/system/modules/DiffieHellman/DiffieHellman.php';
if (strlen($this->Input->get("key")) == 0) {
throw new \Exception("Could not find public key for handshake.");
}
// Load information
$arrConnections = $this->Database->prepare("SELECT * FROM tl_ctocom_cache WHERE uid=?")->execute($this->Input->get("con"))->fetchAllAssoc();
// Start key gen
$objDiffieHellman = new \Crypt_DiffieHellman($arrConnections[0]["prime"], $arrConnections[0]["generator"], $arrConnections[0]["private_key"]);
$objDiffieHellman->generateKeys();
$strSecretKey = $objDiffieHellman->computeSecretKey($this->Input->get("key"))->getSharedSecretKey();
$this->Database->prepare("UPDATE tl_ctocom_cache %s WHERE uid=?")->set(array("tstamp" => time(), "shared_secret_key" => $strSecretKey))->execute($this->Input->get("con"));
return $objDiffieHellman->getPublicKey();
}
}
public function startConnection()
{
/*
* Try to get the Version from client.
* If we get a blank response or a error, the system try to use the
* old AES Codifyengine.
*/
try {
$strVersion = $this->run("CTOCOM_VERSION");
if (version_compare($strVersion, $GLOBALS["CTOCOM_VERSION"], '<')) {
$this->setConnectionBasicCodify("aes");
}
} catch (\RuntimeException $exc) {
\System::log("The client with the adress: " . $this->strUrl . " seems to be an older Version.", __CLASS__ . " | " . __FUNCTION__, TL_INFO);
$this->setConnectionBasicCodify("aes");
}
// Check handshake
if ($GLOBALS['TL_CONFIG']['ctoCom_handshake'] == true) {
// Set flag for API key use
$arrData = array(array("name" => "useAPIK", "value" => true));
// Say "Hello" for connection id
$strMyNumber = $this->run("CTOCOM_HELLO");
$this->client->setConnectionID($strMyNumber);
// Start key handshake
if (!$this->run("CTOCOM_START_HANDSHAKE", $arrData, true)) {
throw new \RuntimeException("Could not set API Key for handshake.");
}
if (!$this->run("CTOCOM_CHECK_HANDSHAKE", $arrData, true)) {
throw new \RuntimeException("Could not set API Key for handshake.");
}
// Save and end
$this->client->setConnectionKey($this->client->getApiKey());
$this->saveConnectionSettings($this->client);
} else {
// Imoprt
require_once TL_ROOT . '/system/modules/DiffieHellman/DiffieHellman.php';
// Say "Hello" for connection id
$strMyNumber = $this->run("CTOCOM_HELLO");
$this->client->setConnectionID($strMyNumber);
// Start key handshake
$arrDiffieHellman = $this->run("CTOCOM_START_HANDSHAKE");
$objLastException = null;
for ($i = 0; $i < 100; $i++) {
// Create random private key.
$intPrivateLength = rand(strlen($arrDiffieHellman["generator"]), strlen($arrDiffieHellman["prime"]) - 2);
$strPrivate = rand(1, 9);
for ($ii = 0; $ii < $intPrivateLength; $ii++) {
$strPrivate .= rand(0, 9);
}
if (!preg_match("/^\\d+\$/", $strPrivate)) {
$objLastException = new \RuntimeException("Private key is not a natural number");
continue;
}
try {
// Start key gen
$objDiffieHellman = new \Crypt_DiffieHellman($arrDiffieHellman["prime"], $arrDiffieHellman["generator"], $strPrivate);
$objDiffieHellman->generateKeys();
// Send public key for check
$arrData = array(array("name" => "key", "value" => $objDiffieHellman->getPublicKey()));
} catch (\RuntimeException $exc) {
$objLastException = $exc;
continue;
}
$objLastException = null;
break;
}
if ($objLastException != null) {
throw $objLastException;
}
$strPublicKey = $this->run("CTOCOM_CHECK_HANDSHAKE", $arrData, true);
if ($arrDiffieHellman["public_key"] != $strPublicKey) {
throw new \RuntimeException("Error for handshake. Public-Key from client isn't valide.");
}
$strSecretKey = $objDiffieHellman->computeSecretKey($arrDiffieHellman["public_key"])->getSharedSecretKey();
// Save and end
$this->client->setConnectionKey($strSecretKey);
$this->saveConnectionSettings($this->client);
}
}
