FEATURE: qBittorrent can now act as a tracker

Changelog

@@ -1,4 +1,5 @@
 * Unreleased - Christophe Dumez <chris@qbittorrent.org> - v2.5.0
+    - FEATURE: qBittorrent can now act as a tracker
     - FEATURE: Added feature to shutdown qbittorrent on torrents completion
     - FEATURE: Added a transfer list column to display the current tracker
     - COSMETIC: Replaced message box by on-screen notification for download errors

src/advancedsettings.h

@@ -11,15 +11,15 @@
 #include "preferences.h"
 
 enum AdvSettingsCols {PROPERTY, VALUE};
-enum AdvSettingsRows {DISK_CACHE, OUTGOING_PORT_MIN, OUTGOING_PORT_MAX, IGNORE_LIMIT_LAN, COUNT_OVERHEAD, RECHECK_COMPLETED, LIST_REFRESH, RESOLVE_COUNTRIES, RESOLVE_HOSTS, MAX_HALF_OPEN, SUPER_SEEDING, NETWORK_IFACE, PROGRAM_NOTIFICATIONS };
+enum AdvSettingsRows {DISK_CACHE, OUTGOING_PORT_MIN, OUTGOING_PORT_MAX, IGNORE_LIMIT_LAN, COUNT_OVERHEAD, RECHECK_COMPLETED, LIST_REFRESH, RESOLVE_COUNTRIES, RESOLVE_HOSTS, MAX_HALF_OPEN, SUPER_SEEDING, NETWORK_IFACE, PROGRAM_NOTIFICATIONS, TRACKER_STATUS, TRACKER_PORT };
-#define ROW_COUNT 13
+#define ROW_COUNT 15
 
 class AdvancedSettings: public QTableWidget {
   Q_OBJECT
 
 private:
-  QSpinBox *spin_cache, *outgoing_ports_min, *outgoing_ports_max, *spin_list_refresh, *spin_maxhalfopen;
+  QSpinBox *spin_cache, *outgoing_ports_min, *outgoing_ports_max, *spin_list_refresh, *spin_maxhalfopen, *spin_tracker_port;
-  QCheckBox *cb_ignore_limits_lan, *cb_count_overhead, *cb_recheck_completed, *cb_resolve_countries, *cb_resolve_hosts, *cb_super_seeding, *cb_program_notifications;
+  QCheckBox *cb_ignore_limits_lan, *cb_count_overhead, *cb_recheck_completed, *cb_resolve_countries, *cb_resolve_hosts, *cb_super_seeding, *cb_program_notifications, *cb_tracker_status;
   QComboBox *combo_iface;
 
 public:
@@ -53,6 +53,8 @@ public:
     delete cb_super_seeding;
     delete combo_iface;
     delete cb_program_notifications;
+    delete spin_tracker_port;
+    delete cb_tracker_status;
   }
 
 public slots:
@@ -88,6 +90,9 @@ public slots:
     }
     // Program notification
     Preferences::useProgramNotification(cb_program_notifications->isChecked());
+    // Tracker
+    Preferences::setTrackerEnabled(cb_tracker_status->isChecked());
+    Preferences::setTrackerPort(spin_tracker_port->value());
   }
 
 protected slots:
@@ -195,6 +200,20 @@ protected slots:
     connect(cb_program_notifications, SIGNAL(toggled(bool)), this, SLOT(emitSettingsChanged()));
     cb_program_notifications->setChecked(Preferences::useProgramNotification());
     setCellWidget(PROGRAM_NOTIFICATIONS, VALUE, cb_program_notifications);
+    // Tracker State
+    setItem(TRACKER_STATUS, PROPERTY, new QTableWidgetItem(tr("Enable embedded tracker")));
+    cb_tracker_status = new QCheckBox();
+    connect(cb_tracker_status, SIGNAL(toggled(bool)), this, SLOT(emitSettingsChanged()));
+    cb_tracker_status->setChecked(Preferences::isTrackerEnabled());
+    setCellWidget(TRACKER_STATUS, VALUE, cb_tracker_status);
+    // Tracker port
+    setItem(TRACKER_PORT, PROPERTY, new QTableWidgetItem(tr("Embedded tracker port")));
+    spin_tracker_port = new QSpinBox();
+    connect(spin_tracker_port, SIGNAL(valueChanged(int)), this, SLOT(emitSettingsChanged()));
+    spin_tracker_port->setMinimum(1);
+    spin_tracker_port->setMaximum(65535);
+    spin_tracker_port->setValue(Preferences::getTrackerPort());
+    setCellWidget(TRACKER_PORT, VALUE, spin_tracker_port);
   }
 
   void emitSettingsChanged() {

src/preferences.h

@@ -1192,6 +1192,26 @@ public:
 
 #endif
 
+  static bool isTrackerEnabled() {
+    QIniSettings settings("qBittorrent", "qBittorrent");
+    return settings.value(QString::fromUtf8("Preferences/Advanced/trackerEnabled"), false).toBool();
+  }
+
+  static void setTrackerEnabled(bool enabled) {
+    QIniSettings settings("qBittorrent", "qBittorrent");
+    settings.setValue(QString::fromUtf8("Preferences/Advanced/trackerEnabled"), enabled);
+  }
+
+  static int getTrackerPort() {
+    QIniSettings settings("qBittorrent", "qBittorrent");
+    return settings.value(QString::fromUtf8("Preferences/Advanced/trackerPort"), 9000).toInt();
+  }
+
+  static void setTrackerPort(int port) {
+    QIniSettings settings("qBittorrent", "qBittorrent");
+    settings.setValue(QString::fromUtf8("Preferences/Advanced/trackerPort"), port);
+  }
+
 };
 
 #endif // PREFERENCES_H

src/qtlibtorrent/qbtsession.cpp

@@ -84,6 +84,7 @@ Bittorrent::Bittorrent()
   , geoipDBLoaded(false), resolve_countries(false)
 #endif
 {
+  m_tracker = 0;
   // To avoid some exceptions
   fs::path::default_name_check(fs::no_check);
   // For backward compatibility
@@ -171,6 +172,8 @@ Bittorrent::~Bittorrent() {
     delete s;
   }
   // Delete our objects
+  if(m_tracker)
+    delete m_tracker;
   delete timerAlerts;
   if(BigRatioTimer)
     delete BigRatioTimer;
@@ -594,6 +597,21 @@ void Bittorrent::configureSession() {
     http_proxySettings.type = proxy_settings::none;
   }
   setHTTPProxySettings(http_proxySettings);
+  // Tracker
+  if(Preferences::isTrackerEnabled()) {
+    if(!m_tracker) {
+      m_tracker = new QTracker(this);
+    }
+    if(m_tracker->start()) {
+      addConsoleMessage(tr("Embedded Tracker [ON]"), QString::fromUtf8("blue"));
+    } else {
+      addConsoleMessage(tr("Failed to start the embedded tracker!"), QString::fromUtf8("red"));
+    }
+  } else {
+    addConsoleMessage(tr("Embedded Tracker [OFF]"));
+    if(m_tracker)
+      delete m_tracker;
+  }
   qDebug("Session configured");
 }
 

src/qtlibtorrent/qbtsession.h

@@ -47,6 +47,7 @@
 #include <libtorrent/session.hpp>
 #include <libtorrent/ip_filter.hpp>
 
+#include "qtracker.h"
 #include "qtorrenthandle.h"
 #include "trackerinfos.h"
 
@@ -250,6 +251,8 @@ private:
   bool geoipDBLoaded;
   bool resolve_countries;
 #endif
+  // Tracker
+  QPointer<QTracker> m_tracker;
 
 };
 

src/src.pro

@@ -355,6 +355,7 @@ contains(DEFINES, USE_SYSTEM_QTSINGLEAPPLICATION) {
 include(qtlibtorrent/qtlibtorrent.pri)
 include(webui/webui.pri)
 include(rss/rss.pri)
+include(tracker/tracker.pri)
 
 !contains(DEFINES, DISABLE_GUI) {
   FORMS += ui/mainwindow.ui \

src/tracker/qpeer.h

@@ -0,0 +1,37 @@
+#ifndef QPEER_H
+#define QPEER_H
+
+#include <libtorrent/entry.hpp>
+#include <QString>
+
+using namespace libtorrent;
+
+struct QPeer {
+
+  bool operator!=(const QPeer &other) const {
+    return qhash() != other.qhash();
+  }
+
+  bool operator==(const QPeer &other) const {
+    return qhash() == other.qhash();
+  }
+
+  QString qhash() const {
+    return ip+":"+QString::number(port);
+  }
+
+  entry toEntry(bool no_peer_id) const {
+    entry::dictionary_type peer_map;
+    if(!no_peer_id)
+      peer_map["id"] = entry(peer_id.toStdString());
+    peer_map["ip"] = entry(ip.toStdString());
+    peer_map["port"] = entry(port);
+    return entry(peer_map);
+  }
+
+  QString ip;
+  QString peer_id;
+  int port;
+};
+
+#endif // QPEER_H

src/tracker/qtracker.cpp

@@ -0,0 +1,236 @@
+/*
+ * Bittorrent Client using Qt4 and libtorrent.
+ * Copyright (C) 2006  Christophe Dumez
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * In addition, as a special exception, the copyright holders give permission to
+ * link this program with the OpenSSL project's "OpenSSL" library (or with
+ * modified versions of it that use the same license as the "OpenSSL" library),
+ * and distribute the linked executables. You must obey the GNU General Public
+ * License in all respects for all of the code used other than "OpenSSL".  If you
+ * modify file(s), you may extend this exception to your version of the file(s),
+ * but you are not obligated to do so. If you do not wish to do so, delete this
+ * exception statement from your version.
+ *
+ * Contact : chris@qbittorrent.org
+ */
+
+#include <QHttpRequestHeader>
+#include <QTcpSocket>
+
+#include <libtorrent/bencode.hpp>
+#include <libtorrent/entry.hpp>
+
+#include "qtracker.h"
+#include "preferences.h"
+
+using namespace libtorrent;
+
+QTracker::QTracker(QObject *parent) :
+  QTcpServer(parent)
+{
+  Q_ASSERT(Preferences::isTrackerEnabled());
+  connect(this, SIGNAL(newConnection()), this, SLOT(handlePeerConnection()));
+}
+
+QTracker::~QTracker() {
+  if(isListening()) {
+    qDebug("Shutting down the embedded tracker...");
+    close();
+  }
+  // TODO: Store the torrent list
+}
+
+void QTracker::handlePeerConnection()
+{
+  QTcpSocket *socket;
+  while((socket = nextPendingConnection()))
+  {
+    qDebug("QTracker: New peer connection");
+    connect(socket, SIGNAL(readyRead()), SLOT(readRequest()));
+  }
+}
+
+bool QTracker::start()
+{
+  const int listen_port = Preferences::getTrackerPort();
+  //
+  if(isListening()) {
+    if(serverPort() == listen_port) {
+      // Already listening on the right port, just return
+      return true;
+    }
+    // Wrong port, closing the server
+    close();
+  }
+  qDebug("Starting the embedded tracker...");
+  // Listen on the predefined port
+  return listen(QHostAddress::Any, listen_port);
+}
+
+void QTracker::readRequest()
+{
+  QTcpSocket *socket = static_cast<QTcpSocket*>(sender());
+  QByteArray input = socket->readAll();
+  //qDebug("QTracker: Raw request:\n%s", input.data());
+  HttpRequestParser parser;
+  parser.write(input);
+  if(!parser.isValid()) {
+    qDebug("QTracker: Invalid HTTP Request:\n %s", qPrintable(parser.toString()));
+    respondInvalidRequest(socket, 100, "Invalid request type");
+    return;
+  }
+  //qDebug("QTracker received the following request:\n%s", qPrintable(parser.toString()));
+  // Request is correct, is it a GET request?
+  if(parser.method() != "GET") {
+    qDebug("QTracker: Unsupported HTTP request: %s", qPrintable(parser.method()));
+    respondInvalidRequest(socket, 100, "Invalid request type");
+    return;
+  }
+  if(!parser.url().startsWith("/announce", Qt::CaseInsensitive)) {
+    qDebug("QTracker: Unrecognized path: %s", qPrintable(parser.url()));
+    respondInvalidRequest(socket, 100, "Invalid request type");
+    return;
+  }
+  // OK, this is a GET request
+  respondToAnnounceRequest(socket, parser);
+}
+
+void QTracker::respondInvalidRequest(QTcpSocket *socket, int code, QString msg)
+{
+  QHttpResponseHeader response;
+  response.setStatusLine(code, msg);
+  socket->write(response.toString().toLocal8Bit());
+  socket->disconnectFromHost();
+}
+
+void QTracker::respondToAnnounceRequest(QTcpSocket *socket, const HttpRequestParser& parser)
+{
+  TrackerAnnounceRequest annonce_req;
+  // IP
+  annonce_req.peer.ip = socket->peerAddress().toString();
+  // 1. Get info_hash
+  if(parser.get("info_hash").isNull()) {
+    qDebug("QTracker: Missing info_hash");
+    respondInvalidRequest(socket, 101, "Missing info_hash");
+    return;
+  }
+  annonce_req.info_hash = parser.get("info_hash");
+  // info_hash cannot be longer than 20 bytes
+  if(annonce_req.info_hash.toAscii().length() > 20) {
+    qDebug("QTracker: Info_hash is not 20 byte long: %s (%d)", qPrintable(annonce_req.info_hash), annonce_req.info_hash.toAscii().length());
+    respondInvalidRequest(socket, 150, "Invalid infohash");
+    return;
+  }
+  // 2. Get peer ID
+  if(parser.get("peer_id").isNull()) {
+    qDebug("QTracker: Missing peer_id");
+    respondInvalidRequest(socket, 102, "Missing peer_id");
+    return;
+  }
+  annonce_req.peer.peer_id = parser.get("peer_id");
+  // peer_id cannot be longer than 20 bytes
+  if(annonce_req.peer.peer_id.length() > 20) {
+    qDebug("QTracker: peer_id is not 20 byte long: %s", qPrintable(annonce_req.peer.peer_id));
+    respondInvalidRequest(socket, 151, "Invalid peerid");
+    return;
+  }
+  // 3. Get port
+  if(parser.get("port").isNull()) {
+    qDebug("QTracker: Missing port");
+    respondInvalidRequest(socket, 103, "Missing port");
+    return;
+  }
+  bool ok = false;
+  annonce_req.peer.port = parser.get("port").toInt(&ok);
+  if(!ok || annonce_req.peer.port < 1 || annonce_req.peer.port > 65535) {
+    qDebug("QTracker: Invalid port number (%d)", annonce_req.peer.port);
+    respondInvalidRequest(socket, 103, "Missing port");
+    return;
+  }
+  // 4.  Get event
+  annonce_req.event = "";
+  if(!parser.get("event").isNull()) {
+    annonce_req.event = parser.get("event");
+    qDebug("QTracker: event is %s", qPrintable(annonce_req.event));
+  }
+  // 5. Get numwant
+  annonce_req.numwant = 50;
+  if(!parser.get("numwant").isNull()) {
+    int tmp = parser.get("numwant").toInt();
+    if(tmp > 0) {
+      qDebug("QTracker: numwant=%d", tmp);
+      annonce_req.numwant = tmp;
+    }
+  }
+  // 6. no_peer_id (extension)
+  annonce_req.no_peer_id = false;
+  if(parser.hasKey("no_peer_id")) {
+    annonce_req.no_peer_id = true;
+  }
+  // 7. TODO: support "compact" extension
+  // Done parsing, now let's reply
+  if(m_torrents.contains(annonce_req.info_hash)) {
+    if(annonce_req.event == "stopped") {
+      qDebug("QTracker: Peer stopped downloading, deleting it from the list");
+      m_torrents[annonce_req.info_hash].remove(annonce_req.peer.qhash());
+      return;
+    }
+  } else {
+    // Unknown torrent
+    if(m_torrents.size() == MAX_TORRENTS) {
+      // Reached max size, remove a random torrent
+      m_torrents.erase(m_torrents.begin());
+    }
+  }
+  // Register the user
+  PeerList peers = m_torrents.value(annonce_req.info_hash);
+  if(peers.size() == MAX_PEERS_PER_TORRENT) {
+    // Too many peers, remove a random one
+    peers.erase(peers.begin());
+  }
+  peers[annonce_req.peer.qhash()] = annonce_req.peer;
+  m_torrents[annonce_req.info_hash] = peers;
+  // Reply
+  ReplyWithPeerList(socket, annonce_req);
+}
+
+void QTracker::ReplyWithPeerList(QTcpSocket *socket, const TrackerAnnounceRequest &annonce_req)
+{
+  // Prepare the entry for bencoding
+  entry::dictionary_type reply_dict;
+  reply_dict["interval"] = entry(ANNOUNCE_INTERVAL);
+  QList<QPeer> peers = m_torrents.value(annonce_req.info_hash).values();
+  entry::list_type peer_list;
+  foreach(const QPeer & p, peers) {
+    //if(p != annonce_req.peer)
+      peer_list.push_back(p.toEntry(annonce_req.no_peer_id));
+  }
+  reply_dict["peers"] = entry(peer_list);
+  entry reply_entry(reply_dict);
+  // bencode
+  std::vector<char> buf;
+  bencode(std::back_inserter(buf), reply_entry);
+  QByteArray reply(buf.data(), buf.size());
+  qDebug("QTracker: reply with the following bencoded data:\n %s", reply.constData());
+  // HTTP reply
+  QHttpResponseHeader response;
+  response.setStatusLine(200, "OK");
+  socket->write(response.toString().toLocal8Bit() + reply);
+  socket->disconnectFromHost();
+}
+
+

src/tracker/qtracker.h

@@ -0,0 +1,72 @@
+/*
+ * Bittorrent Client using Qt4 and libtorrent.
+ * Copyright (C) 2010  Christophe Dumez
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * In addition, as a special exception, the copyright holders give permission to
+ * link this program with the OpenSSL project's "OpenSSL" library (or with
+ * modified versions of it that use the same license as the "OpenSSL" library),
+ * and distribute the linked executables. You must obey the GNU General Public
+ * License in all respects for all of the code used other than "OpenSSL".  If you
+ * modify file(s), you may extend this exception to your version of the file(s),
+ * but you are not obligated to do so. If you do not wish to do so, delete this
+ * exception statement from your version.
+ *
+ * Contact : chris@qbittorrent.org
+ */
+
+#ifndef QTRACKER_H
+#define QTRACKER_H
+
+#include <QTcpServer>
+#include <QHttpResponseHeader>
+#include <QHash>
+
+#include "httprequestparser.h"
+#include "trackerannouncerequest.h"
+#include "qpeer.h"
+
+// static limits
+const int MAX_TORRENTS = 100;
+const int MAX_PEERS_PER_TORRENT = 1000;
+const int ANNOUNCE_INTERVAL = 1800; // 30min
+
+typedef QHash<QString, QPeer> PeerList;
+typedef QHash<QString, PeerList> TorrentList;
+
+/* Basic Bittorrent tracker implementation in Qt4 */
+/* Following http://wiki.theory.org/BitTorrent_Tracker_Protocol */
+class QTracker : public QTcpServer
+{
+  Q_OBJECT
+public:
+  explicit QTracker(QObject *parent = 0);
+  ~QTracker();
+  bool start();
+
+protected slots:
+  void readRequest();
+  void handlePeerConnection();
+  void respondInvalidRequest(QTcpSocket *socket, int code, QString msg);
+  void respondToAnnounceRequest(QTcpSocket *socket, const HttpRequestParser& parser);
+  void ReplyWithPeerList(QTcpSocket *socket, const TrackerAnnounceRequest &annonce_req);
+
+private:
+  TorrentList m_torrents;
+
+};
+
+#endif // QTRACKER_H

src/tracker/tracker.pri

@@ -0,0 +1,9 @@
+INCLUDEPATH += $$PWD
+
+HEADERS += \
+    $$PWD/qtracker.h \
+    $$PWD/trackerannouncerequest.h \
+    $$PWD/qpeer.h
+
+SOURCES += \
+    $$PWD/qtracker.cpp

src/tracker/trackerannouncerequest.h

@@ -0,0 +1,15 @@
+#ifndef TRACKERANNOUNCEREQUEST_H
+#define TRACKERANNOUNCEREQUEST_H
+
+#include <qpeer.h>
+
+struct TrackerAnnounceRequest {
+  QString info_hash;
+  QString event;
+  int numwant;
+  QPeer peer;
+  // Extensions
+  bool no_peer_id;
+};
+
+#endif // TRACKERANNOUNCEREQUEST_H

src/webui/httprequestparser.cpp

@@ -68,12 +68,12 @@ QByteArray HttpRequestParser::message() const
 
 QString HttpRequestParser::get(const QString key) const
 {
-	return getMap[key];
+        return getMap.value(key);
 }
 
 QString HttpRequestParser::post(const QString key) const
 {
-	return postMap[key];
+        return postMap.value(key);
 }
 
 QByteArray HttpRequestParser::torrent() const