public function decodeServerKeyExchange()
{
$core = $this->core;
$extensions = $core->extensions;
$protoVersion = $core->getProtocolVersion();
/*
* ECCurveType
*
* We only support named curves, which is 0x03
*
* enum { explicit_prime (1), explicit_char2 (2),
* named_curve (3), reserved(248..255) } ECCurveType;
*/
$data = Core::_pack('C', 0x3);
// Named curve type
$data .= Core::_pack('n', $this->namedCurveType);
// ECDH Public Key
$this->ecdh = new EcDH($this->namedCurveType);
$dataPublicKey = $this->ecdh->getPublicKey();
$data .= Core::_pack('C', strlen($dataPublicKey)) . $dataPublicKey;
/*
* Signature
*
* https://tools.ietf.org/html/rfc4492 Page 19
* signed_params: A hash of the params, with the signature appropriate
* to that hash applied. The private key corresponding to the
* certified public key in the server's Certificate message is used
* for signing.
*
* ServerKeyExchange.signed_params.sha_hash
* SHA(ClientHello.random + ServerHello.random +
* ServerKeyExchange.params);
*/
$connIn = $core->getInDuplex();
$connOut = $core->getOutDuplex();
$dataSign = $connIn->random . $connOut->random . $data;
$signature = $extensions->call('SignatureAlgorithm', 'getSignature', null, $dataSign);
if ($protoVersion >= 32) {
// Signature Hash Alogorithm
// [null, null] never happens
list($hash, $sig) = $extensions->call('SignatureAlgorithm', 'getAlgorithm', [null, null]);
$data .= Core::_pack('C', $hash) . Core::_pack('C', $sig);
}
// Append signature
$data .= Core::_pack('n', strlen($signature)) . $signature;
$hs = HandShakeFactory::getInstance($core, HandshakeType::SERVER_KEY_EXCHANGE);
$hs->setMsgType(HandshakeType::SERVER_KEY_EXCHANGE);
$hs->set('length', strlen($data));
return $hs->getBinHeader() . $data;
}
public function encodeHandshake($payload)
{
$core = $this->core;
// Incomming Record
$recordIn = $core->getInDuplex()->getRecord();
// Outgoing Record
$recordOut = $core->getOutDuplex()->getRecord();
// Buffer to send
$bufferOut = $core->getBufferOut();
// Extension
$extensions = $core->extensions;
if ($core->isHandshaked) {
throw new TLSAlertException(Alert::create(Alert::UNEXPECTED_MESSAGE), "Handshake message received after handshake is complete");
}
/*
* https://tools.ietf.org/html/rfc5246#section-7.4
*
* Get Handshake Msg type
*/
$handshakeType = Core::_unpack('C', $payload[0]);
if ($this->expectedHandshakeType != $handshakeType) {
throw new TLSAlertException(Alert::create(Alert::UNEXPECTED_MESSAGE), "Unexpected handshake message: {$handshakeType} <=> " . $this->expectedHandshakeType);
}
$handshake = HandshakeFactory::getInstance($core, $handshakeType);
$handshake->encode($payload);
$this->content = $handshake;
switch ($this->expectedHandshakeType) {
case HandshakeType::SERVER_HELLO:
$this->expectedHandshakeType = HandshakeType::CERTIFICATE;
break;
case HandshakeType::CERTIFICATE:
if ($core->cipherSuite->isECDHEEnabled()) {
$this->expectedHandshakeType = HandshakeType::SERVER_KEY_EXCHANGE;
} else {
$this->expectedHandshakeType = HandshakeType::SERVER_HELLO_DONE;
}
break;
case HandshakeType::SERVER_KEY_EXCHANGE:
$this->expectedHandshakeType = HandshakeType::SERVER_HELLO_DONE;
break;
case HandshakeType::SERVER_HELLO_DONE:
// ===========================================
// Send Client Key Exchange
// ===========================================
$clientKeyExchange = HandshakeFactory::getInstance($core, HandshakeType::CLIENT_KEY_EXCHANGE);
$bufferOut->set($this->decodeContent($clientKeyExchange->decode(), ContentType::HANDSHAKE));
// ===========================================
// Send Change Cipher Spec
// ===========================================
$changeCipherSpec = new ChangeCipherSpec();
$bufferOut->append($this->decodeContent($changeCipherSpec->decode(), ContentType::CHANGE_CIPHER_SPEC));
// Enable encryption
$recordOut->cipherChanged();
// ===========================================
// Send Client finished
// ===========================================
$clientFinished = HandShakeFactory::getInstance($core, HandshakeType::FINISHED);
$bufferOut->append($this->decodeContent($clientFinished->decode(), ContentType::HANDSHAKE));
$this->expectedHandshakeType = HandshakeType::FINISHED;
break;
case HandshakeType::FINISHED:
$core->isHandshaked = true;
break;
}
if (strlen($payload) > $handshake->get('length')) {
$payload = substr($payload, $handshake->get('length'));
$this->encodeHandshake($payload);
}
}