Merge pull request #5216

5ec654b [Qt] update paymentserver license and cleanup ordering (Philip Kaufmann)
4333e26 [Qt] add BIP70 DoS protection test (Philip Kaufmann)
31f8494 [Qt] add BIP70 payment request size DoS protection for URIs (Philip Kaufmann)
2284ccb [Qt] remove dup lock that is done in SetAddressBook() (Philip Kaufmann)
1ec753f [Qt] ensure socket is set to NULL in PaymentServer::ipcSendCommandLine (Philip Kaufmann)
814429d [Qt] add BIP70/BIP71 constants for all messages and mime types (Philip Kaufmann)
b82695b [Qt] make PaymentServer::ipcParseCommandLine void (Philip Kaufmann)

7 files changed, 88 insertions, 43 deletions

diff --git a/src/qt/bitcoin.cpp b/src/qt/bitcoin.cpp
index 9872ebc1f6..123777a71b 100644
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@@ -570,9 +570,9 @@ int main(int argc, char *argv[])
     }
 #ifdef ENABLE_WALLET
     // Parse URIs on command line -- this can affect Params()
-    if (!PaymentServer::ipcParseCommandLine(argc, argv))
-        exit(0);
+    PaymentServer::ipcParseCommandLine(argc, argv);
 #endif
+
     QScopedPointer<const NetworkStyle> networkStyle(NetworkStyle::instantiate(QString::fromStdString(Params().NetworkIDString())));
     assert(!networkStyle.isNull());
     // Allow for separate UI settings for testnets
diff --git a/src/qt/guiconstants.h b/src/qt/guiconstants.h
index f23175049a..8f3e476fd9 100644
--- a/src/qt/guiconstants.h
+++ b/src/qt/guiconstants.h
@@ -38,9 +38,6 @@ static const int TOOLTIP_WRAP_THRESHOLD = 80;
 /* Maximum allowed URI length */
 static const int MAX_URI_LENGTH = 255;
 
-/* Maximum somewhat-sane size of a payment request file */
-static const int MAX_PAYMENT_REQUEST_SIZE = 50000; // bytes
-
 /* QRCodeDialog -- size of exported QR Code image */
 #define EXPORT_IMAGE_SIZE 256
 
diff --git a/src/qt/paymentrequestplus.cpp b/src/qt/paymentrequestplus.cpp
index 7aefffe24a..a40b5bbcd8 100644
--- a/src/qt/paymentrequestplus.cpp
+++ b/src/qt/paymentrequestplus.cpp
@@ -1,5 +1,5 @@
-// Copyright (c) 2011-2013 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Copyright (c) 2011-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 //
diff --git a/src/qt/paymentrequestplus.h b/src/qt/paymentrequestplus.h
index 91c704c520..fbc3a09265 100644
--- a/src/qt/paymentrequestplus.h
+++ b/src/qt/paymentrequestplus.h
@@ -1,5 +1,5 @@
-// Copyright (c) 2011-2013 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Copyright (c) 2011-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_QT_PAYMENTREQUESTPLUS_H
diff --git a/src/qt/paymentserver.cpp b/src/qt/paymentserver.cpp
index 707de55290..bd3dab41a8 100644
--- a/src/qt/paymentserver.cpp
+++ b/src/qt/paymentserver.cpp
@@ -1,11 +1,10 @@
-// Copyright (c) 2011-2013 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Copyright (c) 2011-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "paymentserver.h"
 
 #include "bitcoinunits.h"
-#include "guiconstants.h"
 #include "guiutil.h"
 #include "optionsmodel.h"
 
@@ -19,6 +18,7 @@
 
 #include <openssl/x509.h>
 #include <openssl/x509_vfy.h>
+
 #include <QApplication>
 #include <QByteArray>
 #include <QDataStream>
@@ -46,14 +46,20 @@
 #include <QUrlQuery>
 #endif
 
-using namespace std;
 using namespace boost;
+using namespace std;
 
 const int BITCOIN_IPC_CONNECT_TIMEOUT = 1000; // milliseconds
 const QString BITCOIN_IPC_PREFIX("bitcoin:");
-const char* BITCOIN_REQUEST_MIMETYPE = "application/bitcoin-paymentrequest";
-const char* BITCOIN_PAYMENTACK_MIMETYPE = "application/bitcoin-paymentack";
-const char* BITCOIN_PAYMENTACK_CONTENTTYPE = "application/bitcoin-payment";
+// BIP70 payment protocol messages
+const char* BIP70_MESSAGE_PAYMENTACK = "PaymentACK";
+const char* BIP70_MESSAGE_PAYMENTREQUEST = "PaymentRequest";
+// BIP71 payment protocol media types
+const char* BIP71_MIMETYPE_PAYMENT = "application/bitcoin-payment";
+const char* BIP71_MIMETYPE_PAYMENTACK = "application/bitcoin-paymentack";
+const char* BIP71_MIMETYPE_PAYMENTREQUEST = "application/bitcoin-paymentrequest";
+// BIP70 max payment request size in bytes (DoS protection)
+const qint64 BIP70_MAX_PAYMENTREQUEST_SIZE = 50000;
 
 X509_STORE* PaymentServer::certStore = NULL;
 void PaymentServer::freeCertStore()
@@ -184,7 +190,7 @@ void PaymentServer::LoadRootCAs(X509_STORE* _store)
 // Warning: ipcSendCommandLine() is called early in init,
 // so don't use "emit message()", but "QMessageBox::"!
 //
-bool PaymentServer::ipcParseCommandLine(int argc, char* argv[])
+void PaymentServer::ipcParseCommandLine(int argc, char* argv[])
 {
     for (int i = 1; i < argc; i++)
     {
@@ -192,6 +198,10 @@ bool PaymentServer::ipcParseCommandLine(int argc, char* argv[])
         if (arg.startsWith("-"))
             continue;
 
+        // If the bitcoin: URI contains a payment request, we are not able to detect the
+        // network as that would require fetching and parsing the payment request.
+        // That means clicking such an URI which contains a testnet payment request
+        // will start a mainnet instance and throw a "wrong network" error.
         if (arg.startsWith(BITCOIN_IPC_PREFIX, Qt::CaseInsensitive)) // bitcoin: URI
         {
             savedPaymentRequests.append(arg);
@@ -216,7 +226,7 @@ bool PaymentServer::ipcParseCommandLine(int argc, char* argv[])
             savedPaymentRequests.append(arg);
 
             PaymentRequestPlus request;
-            if (readPaymentRequest(arg, request))
+            if (readPaymentRequestFromFile(arg, request))
             {
                 if (request.getDetails().network() == "main")
                 {
@@ -235,7 +245,6 @@ bool PaymentServer::ipcParseCommandLine(int argc, char* argv[])
             qWarning() << "PaymentServer::ipcSendCommandLine : Payment request file does not exist: " << arg;
         }
     }
-    return true;
 }
 
 //
@@ -254,6 +263,7 @@ bool PaymentServer::ipcSendCommandLine()
         if (!socket->waitForConnected(BITCOIN_IPC_CONNECT_TIMEOUT))
         {
             delete socket;
+            socket = NULL;
             return false;
         }
 
@@ -262,12 +272,14 @@ bool PaymentServer::ipcSendCommandLine()
         out.setVersion(QDataStream::Qt_4_0);
         out << r;
         out.device()->seek(0);
+
         socket->write(block);
         socket->flush();
-
         socket->waitForBytesWritten(BITCOIN_IPC_CONNECT_TIMEOUT);
         socket->disconnectFromServer();
+
         delete socket;
+        socket = NULL;
         fResult = true;
     }
 
@@ -440,7 +452,7 @@ void PaymentServer::handleURIOrFile(const QString& s)
     {
         PaymentRequestPlus request;
         SendCoinsRecipient recipient;
-        if (!readPaymentRequest(s, request))
+        if (!readPaymentRequestFromFile(s, request))
         {
             emit message(tr("Payment request file handling"),
                 tr("Payment request file cannot be read! This can be caused by an invalid payment request file."),
@@ -474,18 +486,25 @@ void PaymentServer::handleURIConnection()
     handleURIOrFile(msg);
 }
 
-bool PaymentServer::readPaymentRequest(const QString& filename, PaymentRequestPlus& request)
+//
+// Warning: readPaymentRequestFromFile() is used in ipcSendCommandLine()
+// so don't use "emit message()", but "QMessageBox::"!
+//
+bool PaymentServer::readPaymentRequestFromFile(const QString& filename, PaymentRequestPlus& request)
 {
     QFile f(filename);
-    if (!f.open(QIODevice::ReadOnly))
-    {
-        qWarning() << "PaymentServer::readPaymentRequest : Failed to open " << filename;
+    if (!f.open(QIODevice::ReadOnly)) {
+        qWarning() << QString("PaymentServer::%1: Failed to open %2").arg(__func__).arg(filename);
         return false;
     }
 
-    if (f.size() > MAX_PAYMENT_REQUEST_SIZE)
-    {
-        qWarning() << "PaymentServer::readPaymentRequest : " << filename << " too large";
+    // BIP70 DoS protection
+    if (f.size() > BIP70_MAX_PAYMENTREQUEST_SIZE) {
+        qWarning() << QString("PaymentServer::%1: Payment request %2 is too large (%3 bytes, allowed %4 bytes).")
+            .arg(__func__)
+            .arg(filename)
+            .arg(f.size())
+            .arg(BIP70_MAX_PAYMENTREQUEST_SIZE);
         return false;
     }
 
@@ -580,10 +599,10 @@ bool PaymentServer::processPaymentRequest(PaymentRequestPlus& request, SendCoins
 void PaymentServer::fetchRequest(const QUrl& url)
 {
     QNetworkRequest netRequest;
-    netRequest.setAttribute(QNetworkRequest::User, "PaymentRequest");
+    netRequest.setAttribute(QNetworkRequest::User, BIP70_MESSAGE_PAYMENTREQUEST);
     netRequest.setUrl(url);
     netRequest.setRawHeader("User-Agent", CLIENT_NAME.c_str());
-    netRequest.setRawHeader("Accept", BITCOIN_REQUEST_MIMETYPE);
+    netRequest.setRawHeader("Accept", BIP71_MIMETYPE_PAYMENTREQUEST);
     netManager->get(netRequest);
 }
 
@@ -594,11 +613,11 @@ void PaymentServer::fetchPaymentACK(CWallet* wallet, SendCoinsRecipient recipien
         return;
 
     QNetworkRequest netRequest;
-    netRequest.setAttribute(QNetworkRequest::User, "PaymentACK");
+    netRequest.setAttribute(QNetworkRequest::User, BIP70_MESSAGE_PAYMENTACK);
     netRequest.setUrl(QString::fromStdString(details.payment_url()));
-    netRequest.setHeader(QNetworkRequest::ContentTypeHeader, BITCOIN_PAYMENTACK_CONTENTTYPE);
+    netRequest.setHeader(QNetworkRequest::ContentTypeHeader, BIP71_MIMETYPE_PAYMENT);
     netRequest.setRawHeader("User-Agent", CLIENT_NAME.c_str());
-    netRequest.setRawHeader("Accept", BITCOIN_PAYMENTACK_MIMETYPE);
+    netRequest.setRawHeader("Accept", BIP71_MIMETYPE_PAYMENTACK);
 
     payments::Payment payment;
     payment.set_merchant_data(details.merchant_data());
@@ -616,7 +635,6 @@ void PaymentServer::fetchPaymentACK(CWallet* wallet, SendCoinsRecipient recipien
     else {
         CPubKey newKey;
         if (wallet->GetKeyFromPool(newKey)) {
-            LOCK(wallet->cs_wallet); // SetAddressBook
             CKeyID keyID = newKey.GetID();
             wallet->SetAddressBook(keyID, strAccount, "refund");
 
@@ -646,13 +664,26 @@ void PaymentServer::fetchPaymentACK(CWallet* wallet, SendCoinsRecipient recipien
 void PaymentServer::netRequestFinished(QNetworkReply* reply)
 {
     reply->deleteLater();
-    if (reply->error() != QNetworkReply::NoError)
-    {
+
+    // BIP70 DoS protection
+    if (reply->size() > BIP70_MAX_PAYMENTREQUEST_SIZE) {
+        QString msg = tr("Payment request %2 is too large (%3 bytes, allowed %4 bytes).")
+            .arg(__func__)
+            .arg(reply->request().url().toString())
+            .arg(reply->size())
+            .arg(BIP70_MAX_PAYMENTREQUEST_SIZE);
+
+        qWarning() << QString("PaymentServer::%1:").arg(__func__) << msg;
+        emit message(tr("Payment request DoS protection"), msg, CClientUIInterface::MSG_ERROR);
+        return;
+    }
+
+    if (reply->error() != QNetworkReply::NoError) {
         QString msg = tr("Error communicating with %1: %2")
             .arg(reply->request().url().toString())
             .arg(reply->errorString());
 
-        qWarning() << "PaymentServer::netRequestFinished : " << msg;
+        qWarning() << "PaymentServer::netRequestFinished: " << msg;
         emit message(tr("Payment request error"), msg, CClientUIInterface::MSG_ERROR);
         return;
     }
@@ -660,7 +691,7 @@ void PaymentServer::netRequestFinished(QNetworkReply* reply)
     QByteArray data = reply->readAll();
 
     QString requestType = reply->request().attribute(QNetworkRequest::User).toString();
-    if (requestType == "PaymentRequest")
+    if (requestType == BIP70_MESSAGE_PAYMENTREQUEST)
     {
         PaymentRequestPlus request;
         SendCoinsRecipient recipient;
@@ -676,7 +707,7 @@ void PaymentServer::netRequestFinished(QNetworkReply* reply)
 
         return;
     }
-    else if (requestType == "PaymentACK")
+    else if (requestType == BIP70_MESSAGE_PAYMENTACK)
     {
         payments::PaymentACK paymentACK;
         if (!paymentACK.ParseFromArray(data.data(), data.size()))
diff --git a/src/qt/paymentserver.h b/src/qt/paymentserver.h
index 25b08cde49..e1305b9437 100644
--- a/src/qt/paymentserver.h
+++ b/src/qt/paymentserver.h
@@ -1,5 +1,5 @@
 // Copyright (c) 2011-2014 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_QT_PAYMENTSERVER_H
@@ -40,6 +40,8 @@
 
 class OptionsModel;
 
+class CWallet;
+
 QT_BEGIN_NAMESPACE
 class QApplication;
 class QByteArray;
@@ -50,7 +52,8 @@ class QSslError;
 class QUrl;
 QT_END_NAMESPACE
 
-class CWallet;
+// BIP70 max payment request size in bytes (DoS protection)
+extern const qint64 BIP70_MAX_PAYMENTREQUEST_SIZE;
 
 class PaymentServer : public QObject
 {
@@ -59,7 +62,7 @@ class PaymentServer : public QObject
 public:
     // Parse URIs on command line
     // Returns false on error
-    static bool ipcParseCommandLine(int argc, char *argv[]);
+    static void ipcParseCommandLine(int argc, char *argv[]);
 
     // Returns true if there were URIs on the command line
     // which were successfully sent to an already-running
@@ -85,6 +88,9 @@ public:
     // OptionsModel is used for getting proxy settings and display unit
     void setOptionsModel(OptionsModel *optionsModel);
 
+    // This is now public, because we use it in paymentservertests.cpp
+    static bool readPaymentRequestFromFile(const QString& filename, PaymentRequestPlus& request);
+
 signals:
     // Fired when a valid payment request is received
     void receivedPaymentRequest(SendCoinsRecipient);
@@ -118,7 +124,6 @@ protected:
     bool eventFilter(QObject *object, QEvent *event);
 
 private:
-    static bool readPaymentRequest(const QString& filename, PaymentRequestPlus& request);
     bool processPaymentRequest(PaymentRequestPlus& request, SendCoinsRecipient& recipient);
     void fetchRequest(const QUrl& url);
 
diff --git a/src/qt/test/paymentservertests.cpp b/src/qt/test/paymentservertests.cpp
index 84cab01c50..8f49cb9464 100644
--- a/src/qt/test/paymentservertests.cpp
+++ b/src/qt/test/paymentservertests.cpp
@@ -7,6 +7,7 @@
 #include "optionsmodel.h"
 #include "paymentrequestdata.h"
 
+#include "random.h"
 #include "util.h"
 #include "utilstrencodings.h"
 
@@ -108,6 +109,17 @@ void PaymentServerTests::paymentServerTests()
     r.paymentRequest.getMerchant(caStore, merchant);
     QCOMPARE(merchant, QString(""));
 
+    // Just get some random data big enough to trigger BIP70 DoS protection
+    unsigned char randData[BIP70_MAX_PAYMENTREQUEST_SIZE + 1];
+    GetRandBytes(randData, sizeof(randData));
+    // Write data to a temp file:
+    QTemporaryFile tempFile;
+    tempFile.open();
+    tempFile.write((const char*)randData, sizeof(randData));
+    tempFile.close();
+    // Trigger BIP70 DoS protection
+    QCOMPARE(PaymentServer::readPaymentRequestFromFile(tempFile.fileName(), r.paymentRequest), false);
+
     delete server;
 }