src/qt/paymentserver.cpp

   1 // Copyright (c) 2011-2017 The Bitcoin Core developers
   2 // Distributed under the MIT software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4
   5 #include <qt/paymentserver.h>
   6
   7 #include <qt/bitcoinunits.h>
   8 #include <qt/guiutil.h>
   9 #include <qt/optionsmodel.h>
  10
  11 #include <base58.h>
  12 #include <chainparams.h>
  13 #include <policy/policy.h>
  14 #include <ui_interface.h>
  15 #include <util.h>
  16 #include <wallet/wallet.h>
  17
  18 #include <cstdlib>
  19
  20 #include <openssl/x509_vfy.h>
  21
  22 #include <QApplication>
  23 #include <QByteArray>
  24 #include <QDataStream>
  25 #include <QDateTime>
  26 #include <QDebug>
  27 #include <QFile>
  28 #include <QFileOpenEvent>
  29 #include <QHash>
  30 #include <QList>
  31 #include <QLocalServer>
  32 #include <QLocalSocket>
  33 #include <QNetworkAccessManager>
  34 #include <QNetworkProxy>
  35 #include <QNetworkReply>
  36 #include <QNetworkRequest>
  37 #include <QSslCertificate>
  38 #include <QSslError>
  39 #include <QSslSocket>
  40 #include <QStringList>
  41 #include <QTextDocument>
  42
  43 #if QT_VERSION < 0x050000
  44 #include <QUrl>
  45 #else
  46 #include <QUrlQuery>
  47 #endif
  48
  49 const int BITCOIN_IPC_CONNECT_TIMEOUT = 1000; // milliseconds
  50 const QString BITCOIN_IPC_PREFIX("bitcoin:");
  51 // BIP70 payment protocol messages
  52 const char* BIP70_MESSAGE_PAYMENTACK = "PaymentACK";
  53 const char* BIP70_MESSAGE_PAYMENTREQUEST = "PaymentRequest";
  54 // BIP71 payment protocol media types
  55 const char* BIP71_MIMETYPE_PAYMENT = "application/bitcoin-payment";
  56 const char* BIP71_MIMETYPE_PAYMENTACK = "application/bitcoin-paymentack";
  57 const char* BIP71_MIMETYPE_PAYMENTREQUEST = "application/bitcoin-paymentrequest";
  58
  59 struct X509StoreDeleter {
  60       void operator()(X509_STORE* b) {
  61           X509_STORE_free(b);
  62       }
  63 };
  64
  65 struct X509Deleter {
  66       void operator()(X509* b) { X509_free(b); }
  67 };
  68
  69 namespace // Anon namespace
  70 {
  71     std::unique_ptr<X509_STORE, X509StoreDeleter> certStore;
  72 }
  73
  74 //
  75 // Create a name that is unique for:
  76 //  testnet / non-testnet
  77 //  data directory
  78 //
  79 static QString ipcServerName()
  80 {
  81     QString name("BitcoinQt");
  82
  83     // Append a simple hash of the datadir
  84     // Note that GetDataDir(true) returns a different path
  85     // for -testnet versus main net
  86     QString ddir(GUIUtil::boostPathToQString(GetDataDir(true)));
  87     name.append(QString::number(qHash(ddir)));
  88
  89     return name;
  90 }
  91
  92 //
  93 // We store payment URIs and requests received before
  94 // the main GUI window is up and ready to ask the user
  95 // to send payment.
  96
  97 static QList<QString> savedPaymentRequests;
  98
  99 static void ReportInvalidCertificate(const QSslCertificate& cert)
 100 {
 101 #if QT_VERSION < 0x050000
 102     qDebug() << QString("%1: Payment server found an invalid certificate: ").arg(__func__) << cert.serialNumber() << cert.subjectInfo(QSslCertificate::CommonName) << cert.subjectInfo(QSslCertificate::OrganizationalUnitName);
 103 #else
 104     qDebug() << QString("%1: Payment server found an invalid certificate: ").arg(__func__) << cert.serialNumber() << cert.subjectInfo(QSslCertificate::CommonName) << cert.subjectInfo(QSslCertificate::DistinguishedNameQualifier) << cert.subjectInfo(QSslCertificate::OrganizationalUnitName);
 105 #endif
 106 }
 107
 108 //
 109 // Load OpenSSL's list of root certificate authorities
 110 //
 111 void PaymentServer::LoadRootCAs(X509_STORE* _store)
 112 {
 113     // Unit tests mostly use this, to pass in fake root CAs:
 114     if (_store)
 115     {
 116         certStore.reset(_store);
 117         return;
 118     }
 119
 120     // Normal execution, use either -rootcertificates or system certs:
 121     certStore.reset(X509_STORE_new());
 122
 123     // Note: use "-system-" default here so that users can pass -rootcertificates=""
 124     // and get 'I don't like X.509 certificates, don't trust anybody' behavior:
 125     QString certFile = QString::fromStdString(gArgs.GetArg("-rootcertificates", "-system-"));
 126
 127     // Empty store
 128     if (certFile.isEmpty()) {
 129         qDebug() << QString("PaymentServer::%1: Payment request authentication via X.509 certificates disabled.").arg(__func__);
 130         return;
 131     }
 132
 133     QList<QSslCertificate> certList;
 134
 135     if (certFile != "-system-") {
 136             qDebug() << QString("PaymentServer::%1: Using \"%2\" as trusted root certificate.").arg(__func__).arg(certFile);
 137
 138         certList = QSslCertificate::fromPath(certFile);
 139         // Use those certificates when fetching payment requests, too:
 140         QSslSocket::setDefaultCaCertificates(certList);
 141     } else
 142         certList = QSslSocket::systemCaCertificates();
 143
 144     int nRootCerts = 0;
 145     const QDateTime currentTime = QDateTime::currentDateTime();
 146
 147     for (const QSslCertificate& cert : certList) {
 148         // Don't log NULL certificates
 149         if (cert.isNull())
 150             continue;
 151
 152         // Not yet active/valid, or expired certificate
 153         if (currentTime < cert.effectiveDate() || currentTime > cert.expiryDate()) {
 154             ReportInvalidCertificate(cert);
 155             continue;
 156         }
 157
 158 #if QT_VERSION >= 0x050000
 159         // Blacklisted certificate
 160         if (cert.isBlacklisted()) {
 161             ReportInvalidCertificate(cert);
 162             continue;
 163         }
 164 #endif
 165         QByteArray certData = cert.toDer();
 166         const unsigned char *data = (const unsigned char *)certData.data();
 167
 168         std::unique_ptr<X509, X509Deleter> x509(d2i_X509(0, &data, certData.size()));
 169         if (x509 && X509_STORE_add_cert(certStore.get(), x509.get()))
 170         {
 171             // Note: X509_STORE increases the reference count to the X509 object,
 172             // we still have to release our reference to it.
 173             ++nRootCerts;
 174         }
 175         else
 176         {
 177             ReportInvalidCertificate(cert);
 178             continue;
 179         }
 180     }
 181     qWarning() << "PaymentServer::LoadRootCAs: Loaded " << nRootCerts << " root certificates";
 182
 183     // Project for another day:
 184     // Fetch certificate revocation lists, and add them to certStore.
 185     // Issues to consider:
 186     //   performance (start a thread to fetch in background?)
 187     //   privacy (fetch through tor/proxy so IP address isn't revealed)
 188     //   would it be easier to just use a compiled-in blacklist?
 189     //    or use Qt's blacklist?
 190     //   "certificate stapling" with server-side caching is more efficient
 191 }
 192
 193 //
 194 // Sending to the server is done synchronously, at startup.
 195 // If the server isn't already running, startup continues,
 196 // and the items in savedPaymentRequest will be handled
 197 // when uiReady() is called.
 198 //
 199 // Warning: ipcSendCommandLine() is called early in init,
 200 // so don't use "Q_EMIT message()", but "QMessageBox::"!
 201 //
 202 void PaymentServer::ipcParseCommandLine(int argc, char* argv[])
 203 {
 204     for (int i = 1; i < argc; i++)
 205     {
 206         QString arg(argv[i]);
 207         if (arg.startsWith("-"))
 208             continue;
 209
 210         // If the bitcoin: URI contains a payment request, we are not able to detect the
 211         // network as that would require fetching and parsing the payment request.
 212         // That means clicking such an URI which contains a testnet payment request
 213         // will start a mainnet instance and throw a "wrong network" error.
 214         if (arg.startsWith(BITCOIN_IPC_PREFIX, Qt::CaseInsensitive)) // bitcoin: URI
 215         {
 216             savedPaymentRequests.append(arg);
 217
 218             SendCoinsRecipient r;
 219             if (GUIUtil::parseBitcoinURI(arg, &r) && !r.address.isEmpty())
 220             {
 221                 auto tempChainParams = CreateChainParams(CBaseChainParams::MAIN);
 222
 223                 if (IsValidDestinationString(r.address.toStdString(), *tempChainParams)) {
 224                     SelectParams(CBaseChainParams::MAIN);
 225                 } else {
 226                     tempChainParams = CreateChainParams(CBaseChainParams::TESTNET);
 227                     if (IsValidDestinationString(r.address.toStdString(), *tempChainParams)) {
 228                         SelectParams(CBaseChainParams::TESTNET);
 229                     }
 230                 }
 231             }
 232         }
 233         else if (QFile::exists(arg)) // Filename
 234         {
 235             savedPaymentRequests.append(arg);
 236
 237             PaymentRequestPlus request;
 238             if (readPaymentRequestFromFile(arg, request))
 239             {
 240                 if (request.getDetails().network() == "main")
 241                 {
 242                     SelectParams(CBaseChainParams::MAIN);
 243                 }
 244                 else if (request.getDetails().network() == "test")
 245                 {
 246                     SelectParams(CBaseChainParams::TESTNET);
 247                 }
 248             }
 249         }
 250         else
 251         {
 252             // Printing to debug.log is about the best we can do here, the
 253             // GUI hasn't started yet so we can't pop up a message box.
 254             qWarning() << "PaymentServer::ipcSendCommandLine: Payment request file does not exist: " << arg;
 255         }
 256     }
 257 }
 258
 259 //
 260 // Sending to the server is done synchronously, at startup.
 261 // If the server isn't already running, startup continues,
 262 // and the items in savedPaymentRequest will be handled
 263 // when uiReady() is called.
 264 //
 265 bool PaymentServer::ipcSendCommandLine()
 266 {
 267     bool fResult = false;
 268     for (const QString& r : savedPaymentRequests)
 269     {
 270         QLocalSocket* socket = new QLocalSocket();
 271         socket->connectToServer(ipcServerName(), QIODevice::WriteOnly);
 272         if (!socket->waitForConnected(BITCOIN_IPC_CONNECT_TIMEOUT))
 273         {
 274             delete socket;
 275             socket = nullptr;
 276             return false;
 277         }
 278
 279         QByteArray block;
 280         QDataStream out(&block, QIODevice::WriteOnly);
 281         out.setVersion(QDataStream::Qt_4_0);
 282         out << r;
 283         out.device()->seek(0);
 284
 285         socket->write(block);
 286         socket->flush();
 287         socket->waitForBytesWritten(BITCOIN_IPC_CONNECT_TIMEOUT);
 288         socket->disconnectFromServer();
 289
 290         delete socket;
 291         socket = nullptr;
 292         fResult = true;
 293     }
 294
 295     return fResult;
 296 }
 297
 298 PaymentServer::PaymentServer(QObject* parent, bool startLocalServer) :
 299     QObject(parent),
 300     saveURIs(true),
 301     uriServer(0),
 302     netManager(0),
 303     optionsModel(0)
 304 {
 305     // Verify that the version of the library that we linked against is
 306     // compatible with the version of the headers we compiled against.
 307     GOOGLE_PROTOBUF_VERIFY_VERSION;
 308
 309     // Install global event filter to catch QFileOpenEvents
 310     // on Mac: sent when you click bitcoin: links
 311     // other OSes: helpful when dealing with payment request files
 312     if (parent)
 313         parent->installEventFilter(this);
 314
 315     QString name = ipcServerName();
 316
 317     // Clean up old socket leftover from a crash:
 318     QLocalServer::removeServer(name);
 319
 320     if (startLocalServer)
 321     {
 322         uriServer = new QLocalServer(this);
 323
 324         if (!uriServer->listen(name)) {
 325             // constructor is called early in init, so don't use "Q_EMIT message()" here
 326             QMessageBox::critical(0, tr("Payment request error"),
 327                 tr("Cannot start bitcoin: click-to-pay handler"));
 328         }
 329         else {
 330             connect(uriServer, SIGNAL(newConnection()), this, SLOT(handleURIConnection()));
 331             connect(this, SIGNAL(receivedPaymentACK(QString)), this, SLOT(handlePaymentACK(QString)));
 332         }
 333     }
 334 }
 335
 336 PaymentServer::~PaymentServer()
 337 {
 338     google::protobuf::ShutdownProtobufLibrary();
 339 }
 340
 341 //
 342 // OSX-specific way of handling bitcoin: URIs and PaymentRequest mime types.
 343 // Also used by paymentservertests.cpp and when opening a payment request file
 344 // via "Open URI..." menu entry.
 345 //
 346 bool PaymentServer::eventFilter(QObject *object, QEvent *event)
 347 {
 348     if (event->type() == QEvent::FileOpen) {
 349         QFileOpenEvent *fileEvent = static_cast<QFileOpenEvent*>(event);
 350         if (!fileEvent->file().isEmpty())
 351             handleURIOrFile(fileEvent->file());
 352         else if (!fileEvent->url().isEmpty())
 353             handleURIOrFile(fileEvent->url().toString());
 354
 355         return true;
 356     }
 357
 358     return QObject::eventFilter(object, event);
 359 }
 360
 361 void PaymentServer::initNetManager()
 362 {
 363     if (!optionsModel)
 364         return;
 365     delete netManager;
 366
 367     // netManager is used to fetch paymentrequests given in bitcoin: URIs
 368     netManager = new QNetworkAccessManager(this);
 369
 370     QNetworkProxy proxy;
 371
 372     // Query active SOCKS5 proxy
 373     if (optionsModel->getProxySettings(proxy)) {
 374         netManager->setProxy(proxy);
 375
 376         qDebug() << "PaymentServer::initNetManager: Using SOCKS5 proxy" << proxy.hostName() << ":" << proxy.port();
 377     }
 378     else
 379         qDebug() << "PaymentServer::initNetManager: No active proxy server found.";
 380
 381     connect(netManager, SIGNAL(finished(QNetworkReply*)),
 382             this, SLOT(netRequestFinished(QNetworkReply*)));
 383     connect(netManager, SIGNAL(sslErrors(QNetworkReply*, const QList<QSslError> &)),
 384             this, SLOT(reportSslErrors(QNetworkReply*, const QList<QSslError> &)));
 385 }
 386
 387 void PaymentServer::uiReady()
 388 {
 389     initNetManager();
 390
 391     saveURIs = false;
 392     for (const QString& s : savedPaymentRequests)
 393     {
 394         handleURIOrFile(s);
 395     }
 396     savedPaymentRequests.clear();
 397 }
 398
 399 void PaymentServer::handleURIOrFile(const QString& s)
 400 {
 401     if (saveURIs)
 402     {
 403         savedPaymentRequests.append(s);
 404         return;
 405     }
 406
 407     if (s.startsWith(BITCOIN_IPC_PREFIX, Qt::CaseInsensitive)) // bitcoin: URI
 408     {
 409 #if QT_VERSION < 0x050000
 410         QUrl uri(s);
 411 #else
 412         QUrlQuery uri((QUrl(s)));
 413 #endif
 414         if (uri.hasQueryItem("r")) // payment request URI
 415         {
 416             QByteArray temp;
 417             temp.append(uri.queryItemValue("r"));
 418             QString decoded = QUrl::fromPercentEncoding(temp);
 419             QUrl fetchUrl(decoded, QUrl::StrictMode);
 420
 421             if (fetchUrl.isValid())
 422             {
 423                 qDebug() << "PaymentServer::handleURIOrFile: fetchRequest(" << fetchUrl << ")";
 424                 fetchRequest(fetchUrl);
 425             }
 426             else
 427             {
 428                 qWarning() << "PaymentServer::handleURIOrFile: Invalid URL: " << fetchUrl;
 429                 Q_EMIT message(tr("URI handling"),
 430                     tr("Payment request fetch URL is invalid: %1").arg(fetchUrl.toString()),
 431                     CClientUIInterface::ICON_WARNING);
 432             }
 433
 434             return;
 435         }
 436         else // normal URI
 437         {
 438             SendCoinsRecipient recipient;
 439             if (GUIUtil::parseBitcoinURI(s, &recipient))
 440             {
 441                 if (!IsValidDestinationString(recipient.address.toStdString())) {
 442                     Q_EMIT message(tr("URI handling"), tr("Invalid payment address %1").arg(recipient.address),
 443                         CClientUIInterface::MSG_ERROR);
 444                 }
 445                 else
 446                     Q_EMIT receivedPaymentRequest(recipient);
 447             }
 448             else
 449                 Q_EMIT message(tr("URI handling"),
 450                     tr("URI cannot be parsed! This can be caused by an invalid Bitcoin address or malformed URI parameters."),
 451                     CClientUIInterface::ICON_WARNING);
 452
 453             return;
 454         }
 455     }
 456
 457     if (QFile::exists(s)) // payment request file
 458     {
 459         PaymentRequestPlus request;
 460         SendCoinsRecipient recipient;
 461         if (!readPaymentRequestFromFile(s, request))
 462         {
 463             Q_EMIT message(tr("Payment request file handling"),
 464                 tr("Payment request file cannot be read! This can be caused by an invalid payment request file."),
 465                 CClientUIInterface::ICON_WARNING);
 466         }
 467         else if (processPaymentRequest(request, recipient))
 468             Q_EMIT receivedPaymentRequest(recipient);
 469
 470         return;
 471     }
 472 }
 473
 474 void PaymentServer::handleURIConnection()
 475 {
 476     QLocalSocket *clientConnection = uriServer->nextPendingConnection();
 477
 478     while (clientConnection->bytesAvailable() < (int)sizeof(quint32))
 479         clientConnection->waitForReadyRead();
 480
 481     connect(clientConnection, SIGNAL(disconnected()),
 482             clientConnection, SLOT(deleteLater()));
 483
 484     QDataStream in(clientConnection);
 485     in.setVersion(QDataStream::Qt_4_0);
 486     if (clientConnection->bytesAvailable() < (int)sizeof(quint16)) {
 487         return;
 488     }
 489     QString msg;
 490     in >> msg;
 491
 492     handleURIOrFile(msg);
 493 }
 494
 495 //
 496 // Warning: readPaymentRequestFromFile() is used in ipcSendCommandLine()
 497 // so don't use "Q_EMIT message()", but "QMessageBox::"!
 498 //
 499 bool PaymentServer::readPaymentRequestFromFile(const QString& filename, PaymentRequestPlus& request)
 500 {
 501     QFile f(filename);
 502     if (!f.open(QIODevice::ReadOnly)) {
 503         qWarning() << QString("PaymentServer::%1: Failed to open %2").arg(__func__).arg(filename);
 504         return false;
 505     }
 506
 507     // BIP70 DoS protection
 508     if (!verifySize(f.size())) {
 509         return false;
 510     }
 511
 512     QByteArray data = f.readAll();
 513
 514     return request.parse(data);
 515 }
 516
 517 bool PaymentServer::processPaymentRequest(const PaymentRequestPlus& request, SendCoinsRecipient& recipient)
 518 {
 519     if (!optionsModel)
 520         return false;
 521
 522     if (request.IsInitialized()) {
 523         // Payment request network matches client network?
 524         if (!verifyNetwork(request.getDetails())) {
 525             Q_EMIT message(tr("Payment request rejected"), tr("Payment request network doesn't match client network."),
 526                 CClientUIInterface::MSG_ERROR);
 527
 528             return false;
 529         }
 530
 531         // Make sure any payment requests involved are still valid.
 532         // This is re-checked just before sending coins in WalletModel::sendCoins().
 533         if (verifyExpired(request.getDetails())) {
 534             Q_EMIT message(tr("Payment request rejected"), tr("Payment request expired."),
 535                 CClientUIInterface::MSG_ERROR);
 536
 537             return false;
 538         }
 539     } else {
 540         Q_EMIT message(tr("Payment request error"), tr("Payment request is not initialized."),
 541             CClientUIInterface::MSG_ERROR);
 542
 543         return false;
 544     }
 545
 546     recipient.paymentRequest = request;
 547     recipient.message = GUIUtil::HtmlEscape(request.getDetails().memo());
 548
 549     request.getMerchant(certStore.get(), recipient.authenticatedMerchant);
 550
 551     QList<std::pair<CScript, CAmount> > sendingTos = request.getPayTo();
 552     QStringList addresses;
 553
 554     for (const std::pair<CScript, CAmount>& sendingTo : sendingTos) {
 555         // Extract and check destination addresses
 556         CTxDestination dest;
 557         if (ExtractDestination(sendingTo.first, dest)) {
 558             // Append destination address
 559             addresses.append(QString::fromStdString(EncodeDestination(dest)));
 560         }
 561         else if (!recipient.authenticatedMerchant.isEmpty()) {
 562             // Unauthenticated payment requests to custom bitcoin addresses are not supported
 563             // (there is no good way to tell the user where they are paying in a way they'd
 564             // have a chance of understanding).
 565             Q_EMIT message(tr("Payment request rejected"),
 566                 tr("Unverified payment requests to custom payment scripts are unsupported."),
 567                 CClientUIInterface::MSG_ERROR);
 568             return false;
 569         }
 570
 571         // Bitcoin amounts are stored as (optional) uint64 in the protobuf messages (see paymentrequest.proto),
 572         // but CAmount is defined as int64_t. Because of that we need to verify that amounts are in a valid range
 573         // and no overflow has happened.
 574         if (!verifyAmount(sendingTo.second)) {
 575             Q_EMIT message(tr("Payment request rejected"), tr("Invalid payment request."), CClientUIInterface::MSG_ERROR);
 576             return false;
 577         }
 578
 579         // Extract and check amounts
 580         CTxOut txOut(sendingTo.second, sendingTo.first);
 581         if (IsDust(txOut, ::dustRelayFee)) {
 582             Q_EMIT message(tr("Payment request error"), tr("Requested payment amount of %1 is too small (considered dust).")
 583                 .arg(BitcoinUnits::formatWithUnit(optionsModel->getDisplayUnit(), sendingTo.second)),
 584                 CClientUIInterface::MSG_ERROR);
 585
 586             return false;
 587         }
 588
 589         recipient.amount += sendingTo.second;
 590         // Also verify that the final amount is still in a valid range after adding additional amounts.
 591         if (!verifyAmount(recipient.amount)) {
 592             Q_EMIT message(tr("Payment request rejected"), tr("Invalid payment request."), CClientUIInterface::MSG_ERROR);
 593             return false;
 594         }
 595     }
 596     // Store addresses and format them to fit nicely into the GUI
 597     recipient.address = addresses.join("<br />");
 598
 599     if (!recipient.authenticatedMerchant.isEmpty()) {
 600         qDebug() << "PaymentServer::processPaymentRequest: Secure payment request from " << recipient.authenticatedMerchant;
 601     }
 602     else {
 603         qDebug() << "PaymentServer::processPaymentRequest: Insecure payment request to " << addresses.join(", ");
 604     }
 605
 606     return true;
 607 }
 608
 609 void PaymentServer::fetchRequest(const QUrl& url)
 610 {
 611     QNetworkRequest netRequest;
 612     netRequest.setAttribute(QNetworkRequest::User, BIP70_MESSAGE_PAYMENTREQUEST);
 613     netRequest.setUrl(url);
 614     netRequest.setRawHeader("User-Agent", CLIENT_NAME.c_str());
 615     netRequest.setRawHeader("Accept", BIP71_MIMETYPE_PAYMENTREQUEST);
 616     netManager->get(netRequest);
 617 }
 618
 619 void PaymentServer::fetchPaymentACK(CWallet* wallet, const SendCoinsRecipient& recipient, QByteArray transaction)
 620 {
 621     const payments::PaymentDetails& details = recipient.paymentRequest.getDetails();
 622     if (!details.has_payment_url())
 623         return;
 624
 625     QNetworkRequest netRequest;
 626     netRequest.setAttribute(QNetworkRequest::User, BIP70_MESSAGE_PAYMENTACK);
 627     netRequest.setUrl(QString::fromStdString(details.payment_url()));
 628     netRequest.setHeader(QNetworkRequest::ContentTypeHeader, BIP71_MIMETYPE_PAYMENT);
 629     netRequest.setRawHeader("User-Agent", CLIENT_NAME.c_str());
 630     netRequest.setRawHeader("Accept", BIP71_MIMETYPE_PAYMENTACK);
 631
 632     payments::Payment payment;
 633     payment.set_merchant_data(details.merchant_data());
 634     payment.add_transactions(transaction.data(), transaction.size());
 635
 636     // Create a new refund address, or re-use:
 637     QString account = tr("Refund from %1").arg(recipient.authenticatedMerchant);
 638     std::string strAccount = account.toStdString();
 639     std::set<CTxDestination> refundAddresses = wallet->GetAccountAddresses(strAccount);
 640     if (!refundAddresses.empty()) {
 641         CScript s = GetScriptForDestination(*refundAddresses.begin());
 642         payments::Output* refund_to = payment.add_refund_to();
 643         refund_to->set_script(&s[0], s.size());
 644     }
 645     else {
 646         CPubKey newKey;
 647         if (wallet->GetKeyFromPool(newKey)) {
 648             CKeyID keyID = newKey.GetID();
 649             wallet->SetAddressBook(keyID, strAccount, "refund");
 650
 651             CScript s = GetScriptForDestination(keyID);
 652             payments::Output* refund_to = payment.add_refund_to();
 653             refund_to->set_script(&s[0], s.size());
 654         }
 655         else {
 656             // This should never happen, because sending coins should have
 657             // just unlocked the wallet and refilled the keypool.
 658             qWarning() << "PaymentServer::fetchPaymentACK: Error getting refund key, refund_to not set";
 659         }
 660     }
 661
 662     int length = payment.ByteSize();
 663     netRequest.setHeader(QNetworkRequest::ContentLengthHeader, length);
 664     QByteArray serData(length, '\0');
 665     if (payment.SerializeToArray(serData.data(), length)) {
 666         netManager->post(netRequest, serData);
 667     }
 668     else {
 669         // This should never happen, either.
 670         qWarning() << "PaymentServer::fetchPaymentACK: Error serializing payment message";
 671     }
 672 }
 673
 674 void PaymentServer::netRequestFinished(QNetworkReply* reply)
 675 {
 676     reply->deleteLater();
 677
 678     // BIP70 DoS protection
 679     if (!verifySize(reply->size())) {
 680         Q_EMIT message(tr("Payment request rejected"),
 681             tr("Payment request %1 is too large (%2 bytes, allowed %3 bytes).")
 682                 .arg(reply->request().url().toString())
 683                 .arg(reply->size())
 684                 .arg(BIP70_MAX_PAYMENTREQUEST_SIZE),
 685             CClientUIInterface::MSG_ERROR);
 686         return;
 687     }
 688
 689     if (reply->error() != QNetworkReply::NoError) {
 690         QString msg = tr("Error communicating with %1: %2")
 691             .arg(reply->request().url().toString())
 692             .arg(reply->errorString());
 693
 694         qWarning() << "PaymentServer::netRequestFinished: " << msg;
 695         Q_EMIT message(tr("Payment request error"), msg, CClientUIInterface::MSG_ERROR);
 696         return;
 697     }
 698
 699     QByteArray data = reply->readAll();
 700
 701     QString requestType = reply->request().attribute(QNetworkRequest::User).toString();
 702     if (requestType == BIP70_MESSAGE_PAYMENTREQUEST)
 703     {
 704         PaymentRequestPlus request;
 705         SendCoinsRecipient recipient;
 706         if (!request.parse(data))
 707         {
 708             qWarning() << "PaymentServer::netRequestFinished: Error parsing payment request";
 709             Q_EMIT message(tr("Payment request error"),
 710                 tr("Payment request cannot be parsed!"),
 711                 CClientUIInterface::MSG_ERROR);
 712         }
 713         else if (processPaymentRequest(request, recipient))
 714             Q_EMIT receivedPaymentRequest(recipient);
 715
 716         return;
 717     }
 718     else if (requestType == BIP70_MESSAGE_PAYMENTACK)
 719     {
 720         payments::PaymentACK paymentACK;
 721         if (!paymentACK.ParseFromArray(data.data(), data.size()))
 722         {
 723             QString msg = tr("Bad response from server %1")
 724                 .arg(reply->request().url().toString());
 725
 726             qWarning() << "PaymentServer::netRequestFinished: " << msg;
 727             Q_EMIT message(tr("Payment request error"), msg, CClientUIInterface::MSG_ERROR);
 728         }
 729         else
 730         {
 731             Q_EMIT receivedPaymentACK(GUIUtil::HtmlEscape(paymentACK.memo()));
 732         }
 733     }
 734 }
 735
 736 void PaymentServer::reportSslErrors(QNetworkReply* reply, const QList<QSslError> &errs)
 737 {
 738     Q_UNUSED(reply);
 739
 740     QString errString;
 741     for (const QSslError& err : errs) {
 742         qWarning() << "PaymentServer::reportSslErrors: " << err;
 743         errString += err.errorString() + "\n";
 744     }
 745     Q_EMIT message(tr("Network request error"), errString, CClientUIInterface::MSG_ERROR);
 746 }
 747
 748 void PaymentServer::setOptionsModel(OptionsModel *_optionsModel)
 749 {
 750     this->optionsModel = _optionsModel;
 751 }
 752
 753 void PaymentServer::handlePaymentACK(const QString& paymentACKMsg)
 754 {
 755     // currently we don't further process or store the paymentACK message
 756     Q_EMIT message(tr("Payment acknowledged"), paymentACKMsg, CClientUIInterface::ICON_INFORMATION | CClientUIInterface::MODAL);
 757 }
 758
 759 bool PaymentServer::verifyNetwork(const payments::PaymentDetails& requestDetails)
 760 {
 761     bool fVerified = requestDetails.network() == Params().NetworkIDString();
 762     if (!fVerified) {
 763         qWarning() << QString("PaymentServer::%1: Payment request network \"%2\" doesn't match client network \"%3\".")
 764             .arg(__func__)
 765             .arg(QString::fromStdString(requestDetails.network()))
 766             .arg(QString::fromStdString(Params().NetworkIDString()));
 767     }
 768     return fVerified;
 769 }
 770
 771 bool PaymentServer::verifyExpired(const payments::PaymentDetails& requestDetails)
 772 {
 773     bool fVerified = (requestDetails.has_expires() && (int64_t)requestDetails.expires() < GetTime());
 774     if (fVerified) {
 775         const QString requestExpires = QString::fromStdString(DateTimeStrFormat("%Y-%m-%d %H:%M:%S", (int64_t)requestDetails.expires()));
 776         qWarning() << QString("PaymentServer::%1: Payment request expired \"%2\".")
 777             .arg(__func__)
 778             .arg(requestExpires);
 779     }
 780     return fVerified;
 781 }
 782
 783 bool PaymentServer::verifySize(qint64 requestSize)
 784 {
 785     bool fVerified = (requestSize <= BIP70_MAX_PAYMENTREQUEST_SIZE);
 786     if (!fVerified) {
 787         qWarning() << QString("PaymentServer::%1: Payment request too large (%2 bytes, allowed %3 bytes).")
 788             .arg(__func__)
 789             .arg(requestSize)
 790             .arg(BIP70_MAX_PAYMENTREQUEST_SIZE);
 791     }
 792     return fVerified;
 793 }
 794
 795 bool PaymentServer::verifyAmount(const CAmount& requestAmount)
 796 {
 797     bool fVerified = MoneyRange(requestAmount);
 798     if (!fVerified) {
 799         qWarning() << QString("PaymentServer::%1: Payment request amount out of allowed range (%2, allowed 0 - %3).")
 800             .arg(__func__)
 801             .arg(requestAmount)
 802             .arg(MAX_MONEY);
 803     }
 804     return fVerified;
 805 }
 806
 807 X509_STORE* PaymentServer::getCertStore()
 808 {
 809     return certStore.get();
 810 }