servatrice/cockatrice/src/remoteclient.cpp
ebbit1q 7108eb42c8
implement custom protobuf debug string creation (#4532)
* implement custom protobuf debug log string creation

* add version guards

* add missing header

* debian10 repository misses headers

* clean up logging messages a bit

* fix some more formatting on debug messages
2022-02-23 23:46:23 +01:00

724 lines
26 KiB
C++

#include "remoteclient.h"
#include "debug_pb_message.h"
#include "main.h"
#include "passwordhasher.h"
#include "pb/event_server_identification.pb.h"
#include "pb/response_activate.pb.h"
#include "pb/response_forgotpasswordrequest.pb.h"
#include "pb/response_login.pb.h"
#include "pb/response_password_salt.pb.h"
#include "pb/response_register.pb.h"
#include "pb/server_message.pb.h"
#include "pb/session_commands.pb.h"
#include "pending_command.h"
#include "settingscache.h"
#include "version_string.h"
#include <QCryptographicHash>
#include <QDebug>
#include <QHostAddress>
#include <QHostInfo>
#include <QList>
#include <QThread>
#include <QTimer>
#include <QWebSocket>
static const unsigned int protocolVersion = 14;
RemoteClient::RemoteClient(QObject *parent)
: AbstractClient(parent), timeRunning(0), lastDataReceived(0), messageInProgress(false), handshakeStarted(false),
usingWebSocket(false), messageLength(0), hashedPassword()
{
clearNewClientFeatures();
int keepalive = SettingsCache::instance().getKeepAlive();
timer = new QTimer(this);
timer->setInterval(keepalive * 1000);
connect(timer, SIGNAL(timeout()), this, SLOT(ping()));
socket = new QTcpSocket(this);
socket->setSocketOption(QAbstractSocket::LowDelayOption, 1);
connect(socket, SIGNAL(connected()), this, SLOT(slotConnected()));
connect(socket, SIGNAL(readyRead()), this, SLOT(readData()));
connect(socket, SIGNAL(error(QAbstractSocket::SocketError)), this,
SLOT(slotSocketError(QAbstractSocket::SocketError)));
websocket = new QWebSocket(QString(), QWebSocketProtocol::VersionLatest, this);
connect(websocket, &QWebSocket::binaryMessageReceived, this, &RemoteClient::websocketMessageReceived);
connect(websocket, &QWebSocket::connected, this, &RemoteClient::slotConnected);
connect(websocket, SIGNAL(error(QAbstractSocket::SocketError)), this,
SLOT(slotWebSocketError(QAbstractSocket::SocketError)));
connect(this, SIGNAL(serverIdentificationEventReceived(const Event_ServerIdentification &)), this,
SLOT(processServerIdentificationEvent(const Event_ServerIdentification &)));
connect(this, SIGNAL(connectionClosedEventReceived(Event_ConnectionClosed)), this,
SLOT(processConnectionClosedEvent(Event_ConnectionClosed)));
connect(this, SIGNAL(sigConnectToServer(QString, unsigned int, QString, QString)), this,
SLOT(doConnectToServer(QString, unsigned int, QString, QString)));
connect(this, SIGNAL(sigDisconnectFromServer()), this, SLOT(doDisconnectFromServer()));
connect(this, SIGNAL(sigRegisterToServer(QString, unsigned int, QString, QString, QString, QString, QString)), this,
SLOT(doRegisterToServer(QString, unsigned int, QString, QString, QString, QString, QString)));
connect(this, SIGNAL(sigActivateToServer(QString)), this, SLOT(doActivateToServer(QString)));
connect(this, SIGNAL(sigRequestForgotPasswordToServer(QString, unsigned int, QString)), this,
SLOT(doRequestForgotPasswordToServer(QString, unsigned int, QString)));
connect(this, SIGNAL(sigSubmitForgotPasswordResetToServer(QString, unsigned int, QString, QString, QString)), this,
SLOT(doSubmitForgotPasswordResetToServer(QString, unsigned int, QString, QString, QString)));
connect(this, SIGNAL(sigSubmitForgotPasswordChallengeToServer(QString, unsigned int, QString, QString)), this,
SLOT(doSubmitForgotPasswordChallengeToServer(QString, unsigned int, QString, QString)));
}
RemoteClient::~RemoteClient()
{
doDisconnectFromServer();
thread()->quit();
}
void RemoteClient::slotSocketError(QAbstractSocket::SocketError /*error*/)
{
QString errorString = socket->errorString();
doDisconnectFromServer();
emit socketError(errorString);
}
void RemoteClient::slotWebSocketError(QAbstractSocket::SocketError /*error*/)
{
QString errorString = websocket->errorString();
if (getStatus() != ClientStatus::StatusDisconnected) {
doDisconnectFromServer();
emit socketError(errorString);
}
}
void RemoteClient::slotConnected()
{
timeRunning = lastDataReceived = 0;
timer->start();
if (!usingWebSocket) {
// dirty hack to be compatible with v14 server
sendCommandContainer(CommandContainer());
getNewCmdId();
// end of hack
}
}
void RemoteClient::processServerIdentificationEvent(const Event_ServerIdentification &event)
{
if (event.protocol_version() != protocolVersion) {
emit protocolVersionMismatch(protocolVersion, event.protocol_version());
setStatus(StatusDisconnecting);
return;
}
serverSupportsPasswordHash = event.server_options() & Event_ServerIdentification::SupportsPasswordHash;
if (getStatus() == StatusRequestingForgotPassword) {
Command_ForgotPasswordRequest cmdForgotPasswordRequest;
cmdForgotPasswordRequest.set_user_name(userName.toStdString());
cmdForgotPasswordRequest.set_clientid(getSrvClientID(lastHostname).toStdString());
PendingCommand *pend = prepareSessionCommand(cmdForgotPasswordRequest);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this,
SLOT(requestForgotPasswordResponse(Response)));
sendCommand(pend);
return;
}
if (getStatus() == StatusSubmitForgotPasswordReset) {
Command_ForgotPasswordReset cmdForgotPasswordReset;
cmdForgotPasswordReset.set_user_name(userName.toStdString());
cmdForgotPasswordReset.set_clientid(getSrvClientID(lastHostname).toStdString());
cmdForgotPasswordReset.set_token(token.toStdString());
if (!password.isEmpty() && serverSupportsPasswordHash) {
auto passwordSalt = PasswordHasher::generateRandomSalt();
hashedPassword = PasswordHasher::computeHash(password, passwordSalt);
cmdForgotPasswordReset.set_hashed_new_password(hashedPassword.toStdString());
} else if (!password.isEmpty()) {
qWarning() << "using plain text password to reset password";
cmdForgotPasswordReset.set_new_password(password.toStdString());
}
PendingCommand *pend = prepareSessionCommand(cmdForgotPasswordReset);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this,
SLOT(submitForgotPasswordResetResponse(Response)));
sendCommand(pend);
return;
}
if (getStatus() == StatusSubmitForgotPasswordChallenge) {
Command_ForgotPasswordChallenge cmdForgotPasswordChallenge;
cmdForgotPasswordChallenge.set_user_name(userName.toStdString());
cmdForgotPasswordChallenge.set_clientid(getSrvClientID(lastHostname).toStdString());
cmdForgotPasswordChallenge.set_email(email.toStdString());
PendingCommand *pend = prepareSessionCommand(cmdForgotPasswordChallenge);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this,
SLOT(submitForgotPasswordChallengeResponse(Response)));
sendCommand(pend);
return;
}
if (getStatus() == StatusRegistering) {
Command_Register cmdRegister;
cmdRegister.set_user_name(userName.toStdString());
if (!password.isEmpty() && serverSupportsPasswordHash) {
auto passwordSalt = PasswordHasher::generateRandomSalt();
hashedPassword = PasswordHasher::computeHash(password, passwordSalt);
cmdRegister.set_hashed_password(hashedPassword.toStdString());
} else if (!password.isEmpty()) {
qWarning() << "using plain text password to register";
cmdRegister.set_password(password.toStdString());
}
cmdRegister.set_email(email.toStdString());
cmdRegister.set_country(country.toStdString());
cmdRegister.set_real_name(realName.toStdString());
cmdRegister.set_clientid(getSrvClientID(lastHostname).toStdString());
PendingCommand *pend = prepareSessionCommand(cmdRegister);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this, SLOT(registerResponse(Response)));
sendCommand(pend);
return;
}
if (getStatus() == StatusActivating) {
Command_Activate cmdActivate;
cmdActivate.set_user_name(userName.toStdString());
cmdActivate.set_token(token.toStdString());
cmdActivate.set_clientid(getSrvClientID(lastHostname).toStdString());
PendingCommand *pend = prepareSessionCommand(cmdActivate);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this, SLOT(activateResponse(Response)));
sendCommand(pend);
return;
}
doLogin();
}
void RemoteClient::doRequestPasswordSalt()
{
setStatus(StatusGettingPasswordSalt);
Command_RequestPasswordSalt cmdRqSalt;
cmdRqSalt.set_user_name(userName.toStdString());
PendingCommand *pend = prepareSessionCommand(cmdRqSalt);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this, SLOT(passwordSaltResponse(Response)));
sendCommand(pend);
}
Command_Login RemoteClient::generateCommandLogin()
{
Command_Login cmdLogin;
cmdLogin.set_user_name(userName.toStdString());
cmdLogin.set_clientid(getSrvClientID(lastHostname).toStdString());
cmdLogin.set_clientver(VERSION_STRING);
if (!clientFeatures.isEmpty()) {
QMap<QString, bool>::iterator i;
for (i = clientFeatures.begin(); i != clientFeatures.end(); ++i)
cmdLogin.add_clientfeatures(i.key().toStdString().c_str());
}
return cmdLogin;
}
void RemoteClient::doLogin()
{
if (!password.isEmpty() && serverSupportsPasswordHash) {
// TODO store and log in using stored hashed password
if (hashedPassword.isEmpty()) {
doRequestPasswordSalt(); // ask salt to create hashedPassword, then log in
} else {
doHashedLogin(); // log in using hashed password instead
}
} else {
// TODO add setting for client to reject unhashed logins
setStatus(StatusLoggingIn);
Command_Login cmdLogin = generateCommandLogin();
if (!password.isEmpty()) {
qWarning() << "using plain text password to log in";
cmdLogin.set_password(password.toStdString());
}
PendingCommand *pend = prepareSessionCommand(cmdLogin);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this, SLOT(loginResponse(Response)));
sendCommand(pend);
}
}
void RemoteClient::doHashedLogin()
{
setStatus(StatusLoggingIn);
Command_Login cmdLogin = generateCommandLogin();
cmdLogin.set_hashed_password(hashedPassword.toStdString());
PendingCommand *pend = prepareSessionCommand(cmdLogin);
connect(pend, SIGNAL(finished(Response, CommandContainer, QVariant)), this, SLOT(loginResponse(Response)));
sendCommand(pend);
}
void RemoteClient::processConnectionClosedEvent(const Event_ConnectionClosed & /*event*/)
{
doDisconnectFromServer();
}
void RemoteClient::passwordSaltResponse(const Response &response)
{
if (response.response_code() == Response::RespOk) {
const Response_PasswordSalt &resp = response.GetExtension(Response_PasswordSalt::ext);
auto passwordSalt = QString::fromStdString(resp.password_salt());
if (passwordSalt.isEmpty()) { // the server does not recognize the user but allows them to enter unregistered
password.clear(); // the password will not be used
doLogin();
} else {
hashedPassword = PasswordHasher::computeHash(password, passwordSalt);
doHashedLogin();
}
} else if (response.response_code() != Response::RespNotConnected) {
emit loginError(response.response_code(), {}, 0, {});
}
}
void RemoteClient::loginResponse(const Response &response)
{
const Response_Login &resp = response.GetExtension(Response_Login::ext);
QString possibleMissingFeatures;
if (resp.missing_features_size() > 0) {
for (int i = 0; i < resp.missing_features_size(); ++i)
possibleMissingFeatures.append("," + QString::fromStdString(resp.missing_features(i)));
}
if (response.response_code() == Response::RespOk) {
setStatus(StatusLoggedIn);
emit userInfoChanged(resp.user_info());
QList<ServerInfo_User> buddyList;
for (int i = resp.buddy_list_size() - 1; i >= 0; --i)
buddyList.append(resp.buddy_list(i));
emit buddyListReceived(buddyList);
QList<ServerInfo_User> ignoreList;
for (int i = resp.ignore_list_size() - 1; i >= 0; --i)
ignoreList.append(resp.ignore_list(i));
emit ignoreListReceived(ignoreList);
if (newMissingFeatureFound(possibleMissingFeatures) && resp.missing_features_size() > 0 &&
SettingsCache::instance().getNotifyAboutUpdates()) {
SettingsCache::instance().setKnownMissingFeatures(possibleMissingFeatures);
emit notifyUserAboutUpdate();
}
} else if (response.response_code() != Response::RespNotConnected) {
QList<QString> missingFeatures;
if (resp.missing_features_size() > 0) {
for (int i = 0; i < resp.missing_features_size(); ++i)
missingFeatures << QString::fromStdString(resp.missing_features(i));
}
emit loginError(response.response_code(), QString::fromStdString(resp.denied_reason_str()),
static_cast<quint32>(resp.denied_end_time()), missingFeatures);
setStatus(StatusDisconnecting);
}
}
void RemoteClient::registerResponse(const Response &response)
{
const Response_Register &resp = response.GetExtension(Response_Register::ext);
switch (response.response_code()) {
case Response::RespRegistrationAccepted:
emit registerAccepted();
doLogin();
break;
case Response::RespRegistrationAcceptedNeedsActivation:
emit registerAcceptedNeedsActivate();
doLogin();
break;
default:
emit registerError(response.response_code(), QString::fromStdString(resp.denied_reason_str()),
static_cast<quint32>(resp.denied_end_time()));
setStatus(StatusDisconnecting);
doDisconnectFromServer();
break;
}
}
void RemoteClient::activateResponse(const Response &response)
{
if (response.response_code() == Response::RespActivationAccepted) {
emit activateAccepted();
doLogin();
} else {
emit activateError();
}
}
void RemoteClient::readData()
{
lastDataReceived = timeRunning;
QByteArray data = socket->readAll();
inputBuffer.append(data);
do {
if (!messageInProgress) {
if (inputBuffer.size() >= 4) {
// dirty hack to be compatible with v14 server that sends 60 bytes of garbage at the beginning
if (!handshakeStarted) {
handshakeStarted = true;
if (inputBuffer.startsWith("<?xm")) {
messageInProgress = true;
messageLength = 60;
}
} else {
// end of hack
messageLength = (((quint32)(unsigned char)inputBuffer[0]) << 24) +
(((quint32)(unsigned char)inputBuffer[1]) << 16) +
(((quint32)(unsigned char)inputBuffer[2]) << 8) +
((quint32)(unsigned char)inputBuffer[3]);
inputBuffer.remove(0, 4);
messageInProgress = true;
}
} else
return;
}
if (inputBuffer.size() < messageLength)
return;
ServerMessage newServerMessage;
newServerMessage.ParseFromArray(inputBuffer.data(), messageLength);
#ifdef QT_DEBUG
qDebug().noquote() << "IN" << getSafeDebugString(newServerMessage);
#endif
inputBuffer.remove(0, messageLength);
messageInProgress = false;
processProtocolItem(newServerMessage);
if (getStatus() == StatusDisconnecting) // use thread-safe getter
doDisconnectFromServer();
} while (!inputBuffer.isEmpty());
}
void RemoteClient::websocketMessageReceived(const QByteArray &message)
{
lastDataReceived = timeRunning;
ServerMessage newServerMessage;
newServerMessage.ParseFromArray(message.data(), message.length());
#ifdef QT_DEBUG
qDebug().noquote() << "IN" << getSafeDebugString(newServerMessage);
#endif
processProtocolItem(newServerMessage);
}
void RemoteClient::sendCommandContainer(const CommandContainer &cont)
{
#if GOOGLE_PROTOBUF_VERSION > 3001000
auto size = static_cast<unsigned int>(cont.ByteSizeLong());
#else
auto size = static_cast<unsigned int>(cont.ByteSize());
#endif
#ifdef QT_DEBUG
qDebug().noquote() << "OUT" << getSafeDebugString(cont);
#endif
QByteArray buf;
if (usingWebSocket) {
buf.resize(size);
cont.SerializeToArray(buf.data(), size);
websocket->sendBinaryMessage(buf);
} else {
buf.resize(size + 4);
cont.SerializeToArray(buf.data() + 4, size);
buf.data()[3] = (unsigned char)size;
buf.data()[2] = (unsigned char)(size >> 8);
buf.data()[1] = (unsigned char)(size >> 16);
buf.data()[0] = (unsigned char)(size >> 24);
socket->write(buf);
}
}
void RemoteClient::connectToHost(const QString &hostname, unsigned int port)
{
usingWebSocket = port == 443 || port == 80 || port == 4748 || port == 8080;
if (usingWebSocket) {
QUrl url(QString("%1://%2:%3/servatrice").arg(port == 443 ? "wss" : "ws").arg(hostname).arg(port));
websocket->open(url);
} else {
socket->connectToHost(hostname, static_cast<quint16>(port));
}
}
void RemoteClient::doConnectToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_password)
{
doDisconnectFromServer();
userName = _userName;
password = _password;
lastHostname = hostname;
lastPort = port;
hashedPassword.clear();
connectToHost(hostname, port);
setStatus(StatusConnecting);
}
void RemoteClient::doRegisterToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_password,
const QString &_email,
const QString &_country,
const QString &_realname)
{
doDisconnectFromServer();
userName = _userName;
password = _password;
email = _email;
country = _country;
realName = _realname;
lastHostname = hostname;
lastPort = port;
hashedPassword.clear();
connectToHost(hostname, port);
setStatus(StatusRegistering);
}
void RemoteClient::doActivateToServer(const QString &_token)
{
doDisconnectFromServer();
token = _token.trimmed();
connectToHost(lastHostname, lastPort);
setStatus(StatusActivating);
}
void RemoteClient::doDisconnectFromServer()
{
timer->stop();
messageInProgress = false;
handshakeStarted = false;
messageLength = 0;
QList<PendingCommand *> pc = pendingCommands.values();
for (const auto &i : pc) {
Response response;
response.set_response_code(Response::RespNotConnected);
response.set_cmd_id(i->getCommandContainer().cmd_id());
i->processResponse(response);
delete i;
}
pendingCommands.clear();
setStatus(StatusDisconnected);
if (websocket->isValid())
websocket->close();
socket->close();
}
void RemoteClient::ping()
{
QMutableMapIterator<int, PendingCommand *> i(pendingCommands);
while (i.hasNext()) {
PendingCommand *pend = i.next().value();
if (pend->tick() > maxTimeout) {
i.remove();
pend->deleteLater();
}
}
int keepalive = SettingsCache::instance().getKeepAlive();
int maxTime = timeRunning - lastDataReceived;
emit maxPingTime(maxTime, maxTimeout);
if (maxTime >= (keepalive * maxTimeout)) {
disconnectFromServer();
emit serverTimeout();
} else {
sendCommand(prepareSessionCommand(Command_Ping()));
++timeRunning;
}
}
void RemoteClient::connectToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_password)
{
emit sigConnectToServer(hostname, port, _userName, _password);
}
void RemoteClient::registerToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_password,
const QString &_email,
const QString &_country,
const QString &_realname)
{
emit sigRegisterToServer(hostname, port, _userName, _password, _email, _country, _realname);
}
void RemoteClient::activateToServer(const QString &_token)
{
emit sigActivateToServer(_token.trimmed());
}
void RemoteClient::disconnectFromServer()
{
SettingsCache::instance().servers().setAutoConnect(false);
emit sigDisconnectFromServer();
}
QString RemoteClient::getSrvClientID(const QString &_hostname)
{
QString srvClientID = SettingsCache::instance().getClientID();
QHostInfo hostInfo = QHostInfo::fromName(_hostname);
if (!hostInfo.error()) {
QHostAddress hostAddress = hostInfo.addresses().first();
srvClientID += hostAddress.toString();
} else {
qWarning() << "ClientID generation host lookup failure [" << hostInfo.errorString() << "]";
srvClientID += _hostname;
}
QString uniqueServerClientID =
QCryptographicHash::hash(srvClientID.toUtf8(), QCryptographicHash::Sha1).toHex().right(15);
return uniqueServerClientID;
}
bool RemoteClient::newMissingFeatureFound(const QString &_serversMissingFeatures)
{
bool newMissingFeature = false;
QStringList serversMissingFeaturesList = _serversMissingFeatures.split(",");
for (const QString &feature : serversMissingFeaturesList) {
if (!feature.isEmpty()) {
if (!SettingsCache::instance().getKnownMissingFeatures().contains(feature))
return true;
}
}
return newMissingFeature;
}
void RemoteClient::clearNewClientFeatures()
{
QString newKnownMissingFeatures;
QStringList existingKnownMissingFeatures = SettingsCache::instance().getKnownMissingFeatures().split(",");
for (const QString &existingKnownFeature : existingKnownMissingFeatures) {
if (!existingKnownFeature.isEmpty()) {
if (!clientFeatures.contains(existingKnownFeature))
newKnownMissingFeatures.append("," + existingKnownFeature);
}
}
SettingsCache::instance().setKnownMissingFeatures(newKnownMissingFeatures);
}
void RemoteClient::requestForgotPasswordToServer(const QString &hostname, unsigned int port, const QString &_userName)
{
emit sigRequestForgotPasswordToServer(hostname, port, _userName);
}
void RemoteClient::submitForgotPasswordResetToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_token,
const QString &_newpassword)
{
emit sigSubmitForgotPasswordResetToServer(hostname, port, _userName, _token.trimmed(), _newpassword);
}
void RemoteClient::doRequestForgotPasswordToServer(const QString &hostname, unsigned int port, const QString &_userName)
{
doDisconnectFromServer();
userName = _userName;
lastHostname = hostname;
lastPort = port;
connectToHost(lastHostname, lastPort);
setStatus(StatusRequestingForgotPassword);
}
void RemoteClient::requestForgotPasswordResponse(const Response &response)
{
const Response_ForgotPasswordRequest &resp = response.GetExtension(Response_ForgotPasswordRequest::ext);
if (response.response_code() == Response::RespOk) {
if (resp.challenge_email()) {
emit sigPromptForForgotPasswordChallenge();
} else
emit sigPromptForForgotPasswordReset();
} else
emit sigForgotPasswordError();
doDisconnectFromServer();
}
void RemoteClient::doSubmitForgotPasswordResetToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_token,
const QString &_newpassword)
{
doDisconnectFromServer();
userName = _userName;
lastHostname = hostname;
lastPort = port;
token = _token.trimmed();
password = _newpassword;
hashedPassword.clear();
connectToHost(lastHostname, lastPort);
setStatus(StatusSubmitForgotPasswordReset);
}
void RemoteClient::submitForgotPasswordResetResponse(const Response &response)
{
if (response.response_code() == Response::RespOk) {
emit sigForgotPasswordSuccess();
} else
emit sigForgotPasswordError();
doDisconnectFromServer();
}
void RemoteClient::submitForgotPasswordChallengeToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_email)
{
emit sigSubmitForgotPasswordChallengeToServer(hostname, port, _userName, _email);
}
void RemoteClient::doSubmitForgotPasswordChallengeToServer(const QString &hostname,
unsigned int port,
const QString &_userName,
const QString &_email)
{
doDisconnectFromServer();
userName = _userName;
lastHostname = hostname;
lastPort = port;
email = _email;
connectToHost(lastHostname, lastPort);
setStatus(StatusSubmitForgotPasswordChallenge);
}
void RemoteClient::submitForgotPasswordChallengeResponse(const Response &response)
{
if (response.response_code() == Response::RespOk) {
emit sigPromptForForgotPasswordReset();
} else
emit sigForgotPasswordError();
doDisconnectFromServer();
}