src/webui/webapplication.cpp

   1 /*
   2  * Bittorrent Client using Qt and libtorrent.
   3  * Copyright (C) 2014-2024  Vladimir Golovnev <glassez@yandex.ru>
   4  * Copyright (C) 2024  Radu Carpa <radu.carpa@cern.ch>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19  *
  20  * In addition, as a special exception, the copyright holders give permission to
  21  * link this program with the OpenSSL project's "OpenSSL" library (or with
  22  * modified versions of it that use the same license as the "OpenSSL" library),
  23  * and distribute the linked executables. You must obey the GNU General Public
  24  * License in all respects for all of the code used other than "OpenSSL".  If you
  25  * modify file(s), you may extend this exception to your version of the file(s),
  26  * but you are not obligated to do so. If you do not wish to do so, delete this
  27  * exception statement from your version.
  28  */
  29
  30 #include "webapplication.h"
  31
  32 #include <algorithm>
  33 #include <chrono>
  34
  35 #include <QDateTime>
  36 #include <QDebug>
  37 #include <QDir>
  38 #include <QFileInfo>
  39 #include <QJsonDocument>
  40 #include <QMetaObject>
  41 #include <QMimeDatabase>
  42 #include <QMimeType>
  43 #include <QNetworkCookie>
  44 #include <QRegularExpression>
  45 #include <QThread>
  46 #include <QTimer>
  47 #include <QUrl>
  48
  49 #include "base/algorithm.h"
  50 #include "base/bittorrent/torrentcreationmanager.h"
  51 #include "base/http/httperror.h"
  52 #include "base/logger.h"
  53 #include "base/preferences.h"
  54 #include "base/types.h"
  55 #include "base/utils/fs.h"
  56 #include "base/utils/io.h"
  57 #include "base/utils/misc.h"
  58 #include "base/utils/random.h"
  59 #include "base/utils/string.h"
  60 #include "api/apierror.h"
  61 #include "api/appcontroller.h"
  62 #include "api/authcontroller.h"
  63 #include "api/logcontroller.h"
  64 #include "api/rsscontroller.h"
  65 #include "api/searchcontroller.h"
  66 #include "api/synccontroller.h"
  67 #include "api/torrentcreatorcontroller.h"
  68 #include "api/torrentscontroller.h"
  69 #include "api/transfercontroller.h"
  70 #include "freediskspacechecker.h"
  71
  72 const int MAX_ALLOWED_FILESIZE = 10 * 1024 * 1024;
  73 const QString DEFAULT_SESSION_COOKIE_NAME = u"SID"_s;
  74
  75 const QString WWW_FOLDER = u":/www"_s;
  76 const QString PUBLIC_FOLDER = u"/public"_s;
  77 const QString PRIVATE_FOLDER = u"/private"_s;
  78
  79 using namespace std::chrono_literals;
  80
  81 const std::chrono::seconds FREEDISKSPACE_CHECK_TIMEOUT = 30s;
  82
  83 namespace
  84 {
  85     QStringMap parseCookie(const QStringView cookieStr)
  86     {
  87         // [rfc6265] 4.2.1. Syntax
  88         QStringMap ret;
  89         const QList<QStringView> cookies = cookieStr.split(u';', Qt::SkipEmptyParts);
  90
  91         for (const auto &cookie : cookies)
  92         {
  93             const int idx = cookie.indexOf(u'=');
  94             if (idx < 0)
  95                 continue;
  96
  97             const QString name = cookie.left(idx).trimmed().toString();
  98             const QString value = Utils::String::unquote(cookie.mid(idx + 1).trimmed()).toString();
  99             ret.insert(name, value);
 100         }
 101         return ret;
 102     }
 103
 104     QUrl urlFromHostHeader(const QString &hostHeader)
 105     {
 106         if (!hostHeader.contains(u"://"))
 107             return {u"http://"_s + hostHeader};
 108         return hostHeader;
 109     }
 110
 111     QString getCachingInterval(QString contentType)
 112     {
 113         contentType = contentType.toLower();
 114
 115         if (contentType.startsWith(u"image/"))
 116             return u"private, max-age=604800"_s;  // 1 week
 117
 118         if ((contentType == Http::CONTENT_TYPE_CSS) || (contentType == Http::CONTENT_TYPE_JS))
 119         {
 120             // short interval in case of program update
 121             return u"private, max-age=43200"_s;  // 12 hrs
 122         }
 123
 124         return u"no-store"_s;
 125     }
 126
 127     QString createLanguagesOptionsHtml()
 128     {
 129         // List language files
 130         const QStringList langFiles = QDir(u":/www/translations"_s)
 131             .entryList({u"webui_*.qm"_s}, QDir::Files, QDir::Name);
 132
 133         QStringList languages;
 134         languages.reserve(langFiles.size());
 135
 136         for (const QString &langFile : langFiles)
 137         {
 138             const auto langCode = QStringView(langFile).sliced(6).chopped(3); // remove "webui_" and ".qm"
 139             const QString entry = u"<option value=\"%1\">%2</option>"_s
 140                 .arg(langCode, Utils::Misc::languageToLocalizedString(langCode));
 141             languages.append(entry);
 142         }
 143
 144         return languages.join(u'\n');
 145     }
 146
 147     bool isValidCookieName(const QString &cookieName)
 148     {
 149         if (cookieName.isEmpty() || (cookieName.size() > 128))
 150             return false;
 151
 152         const QRegularExpression invalidNameRegex {u"[^a-zA-Z0-9_\\-]"_s};
 153         if (invalidNameRegex.match(cookieName).hasMatch())
 154             return false;
 155
 156         return true;
 157     }
 158 }
 159
 160 WebApplication::WebApplication(IApplication *app, QObject *parent)
 161     : ApplicationComponent(app, parent)
 162     , m_cacheID {QString::number(Utils::Random::rand(), 36)}
 163     , m_authController {new AuthController(this, app, this)}
 164     , m_workerThread {new QThread}
 165     , m_freeDiskSpaceChecker {new FreeDiskSpaceChecker}
 166     , m_freeDiskSpaceCheckingTimer {new QTimer(this)}
 167     , m_torrentCreationManager {new BitTorrent::TorrentCreationManager(app, this)}
 168 {
 169     declarePublicAPI(u"auth/login"_s);
 170
 171     configure();
 172     connect(Preferences::instance(), &Preferences::changed, this, &WebApplication::configure);
 173
 174     m_sessionCookieName = Preferences::instance()->getWebAPISessionCookieName();
 175     if (!isValidCookieName(m_sessionCookieName))
 176     {
 177         if (!m_sessionCookieName.isEmpty())
 178         {
 179             LogMsg(tr("Unacceptable session cookie name is specified: '%1'. Default one is used.")
 180                    .arg(m_sessionCookieName), Log::WARNING);
 181         }
 182         m_sessionCookieName = DEFAULT_SESSION_COOKIE_NAME;
 183     }
 184
 185     m_freeDiskSpaceChecker->moveToThread(m_workerThread.get());
 186     connect(m_workerThread.get(), &QThread::finished, m_freeDiskSpaceChecker, &QObject::deleteLater);
 187     m_workerThread->start();
 188
 189     m_freeDiskSpaceCheckingTimer->setInterval(FREEDISKSPACE_CHECK_TIMEOUT);
 190     m_freeDiskSpaceCheckingTimer->setSingleShot(true);
 191     connect(m_freeDiskSpaceCheckingTimer, &QTimer::timeout, m_freeDiskSpaceChecker, &FreeDiskSpaceChecker::check);
 192     connect(m_freeDiskSpaceChecker, &FreeDiskSpaceChecker::checked, m_freeDiskSpaceCheckingTimer, qOverload<>(&QTimer::start));
 193     QMetaObject::invokeMethod(m_freeDiskSpaceChecker, &FreeDiskSpaceChecker::check);
 194 }
 195
 196 WebApplication::~WebApplication()
 197 {
 198     // cleanup sessions data
 199     qDeleteAll(m_sessions);
 200 }
 201
 202 void WebApplication::sendWebUIFile()
 203 {
 204     if (request().path.contains(u'\\'))
 205         throw BadRequestHTTPError();
 206
 207     if (const QList<QStringView> pathItems = QStringView(request().path).split(u'/', Qt::SkipEmptyParts)
 208             ; pathItems.contains(u".") || pathItems.contains(u".."))
 209     {
 210         throw BadRequestHTTPError();
 211     }
 212
 213     const QString path = (request().path != u"/")
 214         ? request().path
 215         : u"/index.html"_s;
 216
 217     Path localPath = m_rootFolder
 218                 / Path(session() ? PRIVATE_FOLDER : PUBLIC_FOLDER)
 219                 / Path(path);
 220     if (!localPath.exists() && session())
 221     {
 222         // try to send public file if there is no private one
 223         localPath = m_rootFolder / Path(PUBLIC_FOLDER) / Path(path);
 224     }
 225
 226     if (m_isAltUIUsed)
 227     {
 228         if (!Utils::Fs::isRegularFile(localPath))
 229             throw InternalServerErrorHTTPError(tr("Unacceptable file type, only regular file is allowed."));
 230
 231         const QString rootFolder = m_rootFolder.data();
 232
 233         QFileInfo fileInfo {localPath.parentPath().data()};
 234         while (fileInfo.path() != rootFolder)
 235         {
 236             if (fileInfo.isSymLink())
 237                 throw InternalServerErrorHTTPError(tr("Symlinks inside alternative UI folder are forbidden."));
 238
 239             fileInfo.setFile(fileInfo.path());
 240         }
 241     }
 242
 243     sendFile(localPath);
 244 }
 245
 246 void WebApplication::translateDocument(QString &data) const
 247 {
 248     const QRegularExpression regex(u"QBT_TR\\((([^\\)]|\\)(?!QBT_TR))+)\\)QBT_TR\\[CONTEXT=([a-zA-Z_][a-zA-Z0-9_]*)\\]"_s);
 249
 250     int i = 0;
 251     bool found = true;
 252     while (i < data.size() && found)
 253     {
 254         QRegularExpressionMatch regexMatch;
 255         i = data.indexOf(regex, i, &regexMatch);
 256         if (i >= 0)
 257         {
 258             const QString sourceText = regexMatch.captured(1);
 259             const QString context = regexMatch.captured(3);
 260
 261             const QString loadedText = m_translationFileLoaded
 262                 ? m_translator.translate(context.toUtf8().constData(), sourceText.toUtf8().constData())
 263                 : QString();
 264             // `loadedText` is empty when translation is not provided
 265             // it should fallback to `sourceText`
 266             QString translation = loadedText.isEmpty() ? sourceText : loadedText;
 267
 268             // Escape quotes to workaround issues with HTML attributes
 269             // FIXME: this is a dirty workaround to deal with broken translation strings:
 270             // 1. Translation strings is the culprit of the issue, they should be fixed instead
 271             // 2. The escaped quote/string is wrong for JS. JS use backslash to escape the quote: "\""
 272             translation.replace(u'"', u"&#34;"_s);
 273
 274             data.replace(i, regexMatch.capturedLength(), translation);
 275             i += translation.length();
 276         }
 277         else
 278         {
 279             found = false; // no more translatable strings
 280         }
 281
 282         data.replace(u"${LANG}"_s, m_currentLocale.left(2));
 283         data.replace(u"${CACHEID}"_s, m_cacheID);
 284     }
 285 }
 286
 287 WebSession *WebApplication::session()
 288 {
 289     return m_currentSession;
 290 }
 291
 292 const Http::Request &WebApplication::request() const
 293 {
 294     return m_request;
 295 }
 296
 297 const Http::Environment &WebApplication::env() const
 298 {
 299     return m_env;
 300 }
 301
 302 void WebApplication::setUsername(const QString &username)
 303 {
 304     m_authController->setUsername(username);
 305 }
 306
 307 void WebApplication::setPasswordHash(const QByteArray &passwordHash)
 308 {
 309     m_authController->setPasswordHash(passwordHash);
 310 }
 311
 312 void WebApplication::doProcessRequest()
 313 {
 314     const QRegularExpressionMatch match = m_apiPathPattern.match(request().path);
 315     if (!match.hasMatch())
 316     {
 317         sendWebUIFile();
 318         return;
 319     }
 320
 321     const QString action = match.captured(u"action"_s);
 322     const QString scope = match.captured(u"scope"_s);
 323
 324     // Check public/private scope
 325     if (!session() && !isPublicAPI(scope, action))
 326         throw ForbiddenHTTPError();
 327
 328     // Find matching API
 329     APIController *controller = nullptr;
 330     if (session())
 331         controller = session()->getAPIController(scope);
 332     if (!controller)
 333     {
 334         if (scope == u"auth")
 335             controller = m_authController;
 336         else
 337             throw NotFoundHTTPError();
 338     }
 339
 340     // Filter HTTP methods
 341     const auto allowedMethodIter = m_allowedMethod.find({scope, action});
 342     if (allowedMethodIter == m_allowedMethod.end())
 343     {
 344         // by default allow both GET, POST methods
 345         if ((m_request.method != Http::METHOD_GET) && (m_request.method != Http::METHOD_POST))
 346             throw MethodNotAllowedHTTPError();
 347     }
 348     else
 349     {
 350         if (*allowedMethodIter != m_request.method)
 351             throw MethodNotAllowedHTTPError();
 352     }
 353
 354     DataMap data;
 355     for (const Http::UploadedFile &torrent : request().files)
 356         data[torrent.filename] = torrent.data;
 357
 358     try
 359     {
 360         const APIResult result = controller->run(action, m_params, data);
 361         switch (result.data.userType())
 362         {
 363         case QMetaType::QJsonDocument:
 364             print(result.data.toJsonDocument().toJson(QJsonDocument::Compact), Http::CONTENT_TYPE_JSON);
 365             break;
 366         case QMetaType::QByteArray:
 367             {
 368                 const auto resultData = result.data.toByteArray();
 369                 print(resultData, (!result.mimeType.isEmpty() ? result.mimeType : Http::CONTENT_TYPE_TXT));
 370                 if (!result.filename.isEmpty())
 371                 {
 372                     setHeader({u"Content-Disposition"_s, u"attachment; filename=\"%1\""_s.arg(result.filename)});
 373                 }
 374             }
 375             break;
 376         case QMetaType::QString:
 377         default:
 378             print(result.data.toString(), Http::CONTENT_TYPE_TXT);
 379             break;
 380         }
 381     }
 382     catch (const APIError &error)
 383     {
 384         // re-throw as HTTPError
 385         switch (error.type())
 386         {
 387         case APIErrorType::AccessDenied:
 388             throw ForbiddenHTTPError(error.message());
 389         case APIErrorType::BadData:
 390             throw UnsupportedMediaTypeHTTPError(error.message());
 391         case APIErrorType::BadParams:
 392             throw BadRequestHTTPError(error.message());
 393         case APIErrorType::Conflict:
 394             throw ConflictHTTPError(error.message());
 395         case APIErrorType::NotFound:
 396             throw NotFoundHTTPError(error.message());
 397         default:
 398             Q_ASSERT(false);
 399         }
 400     }
 401 }
 402
 403 void WebApplication::configure()
 404 {
 405     const auto *pref = Preferences::instance();
 406
 407     const bool isAltUIUsed = pref->isAltWebUIEnabled();
 408     const Path rootFolder = (!isAltUIUsed ? Path(WWW_FOLDER) : pref->getWebUIRootFolder());
 409     if ((isAltUIUsed != m_isAltUIUsed) || (rootFolder != m_rootFolder))
 410     {
 411         m_isAltUIUsed = isAltUIUsed;
 412         m_rootFolder = rootFolder;
 413         m_translatedFiles.clear();
 414         if (!m_isAltUIUsed)
 415             LogMsg(tr("Using built-in WebUI."));
 416         else
 417             LogMsg(tr("Using custom WebUI. Location: \"%1\".").arg(m_rootFolder.toString()));
 418     }
 419
 420     const QString newLocale = pref->getLocale();
 421     if (m_currentLocale != newLocale)
 422     {
 423         m_currentLocale = newLocale;
 424         m_translatedFiles.clear();
 425
 426         m_translationFileLoaded = m_translator.load((m_rootFolder / Path(u"translations/webui_"_s) + newLocale).data());
 427         if (m_translationFileLoaded)
 428         {
 429             LogMsg(tr("WebUI translation for selected locale (%1) has been successfully loaded.")
 430                    .arg(newLocale));
 431         }
 432         else
 433         {
 434             LogMsg(tr("Couldn't load WebUI translation for selected locale (%1).").arg(newLocale), Log::WARNING);
 435         }
 436     }
 437
 438     m_isLocalAuthEnabled = pref->isWebUILocalAuthEnabled();
 439     m_isAuthSubnetWhitelistEnabled = pref->isWebUIAuthSubnetWhitelistEnabled();
 440     m_authSubnetWhitelist = pref->getWebUIAuthSubnetWhitelist();
 441     m_sessionTimeout = pref->getWebUISessionTimeout();
 442
 443     m_domainList = pref->getServerDomains().split(u';', Qt::SkipEmptyParts);
 444     std::for_each(m_domainList.begin(), m_domainList.end(), [](QString &entry) { entry = entry.trimmed(); });
 445
 446     m_isCSRFProtectionEnabled = pref->isWebUICSRFProtectionEnabled();
 447     m_isSecureCookieEnabled = pref->isWebUISecureCookieEnabled();
 448     m_isHostHeaderValidationEnabled = pref->isWebUIHostHeaderValidationEnabled();
 449     m_isHttpsEnabled = pref->isWebUIHttpsEnabled();
 450
 451     m_prebuiltHeaders.clear();
 452     m_prebuiltHeaders.push_back({Http::HEADER_X_XSS_PROTECTION, u"1; mode=block"_s});
 453     m_prebuiltHeaders.push_back({Http::HEADER_X_CONTENT_TYPE_OPTIONS, u"nosniff"_s});
 454
 455     if (!m_isAltUIUsed)
 456     {
 457         m_prebuiltHeaders.push_back({Http::HEADER_CROSS_ORIGIN_OPENER_POLICY, u"same-origin"_s});
 458         m_prebuiltHeaders.push_back({Http::HEADER_REFERRER_POLICY, u"same-origin"_s});
 459     }
 460
 461     const bool isClickjackingProtectionEnabled = pref->isWebUIClickjackingProtectionEnabled();
 462     if (isClickjackingProtectionEnabled)
 463         m_prebuiltHeaders.push_back({Http::HEADER_X_FRAME_OPTIONS, u"SAMEORIGIN"_s});
 464
 465     const QString contentSecurityPolicy =
 466         (m_isAltUIUsed
 467             ? QString()
 468             : u"default-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; script-src 'self' 'unsafe-inline'; object-src 'none'; form-action 'self';"_s)
 469         + (isClickjackingProtectionEnabled ? u" frame-ancestors 'self';"_s : QString())
 470         + (m_isHttpsEnabled ? u" upgrade-insecure-requests;"_s : QString());
 471     if (!contentSecurityPolicy.isEmpty())
 472         m_prebuiltHeaders.push_back({Http::HEADER_CONTENT_SECURITY_POLICY, contentSecurityPolicy});
 473
 474     if (pref->isWebUICustomHTTPHeadersEnabled())
 475     {
 476         const QString customHeaders = pref->getWebUICustomHTTPHeaders();
 477         const QList<QStringView> customHeaderLines = QStringView(customHeaders).trimmed().split(u'\n', Qt::SkipEmptyParts);
 478
 479         for (const QStringView line : customHeaderLines)
 480         {
 481             const int idx = line.indexOf(u':');
 482             if (idx < 0)
 483             {
 484                 // require separator `:` to be present even if `value` field can be empty
 485                 LogMsg(tr("Missing ':' separator in WebUI custom HTTP header: \"%1\"").arg(line.toString()), Log::WARNING);
 486                 continue;
 487             }
 488
 489             const QString header = line.left(idx).trimmed().toString();
 490             const QString value = line.mid(idx + 1).trimmed().toString();
 491             m_prebuiltHeaders.push_back({header, value});
 492         }
 493     }
 494
 495     m_isReverseProxySupportEnabled = pref->isWebUIReverseProxySupportEnabled();
 496     if (m_isReverseProxySupportEnabled)
 497     {
 498         const QStringList proxyList = pref->getWebUITrustedReverseProxiesList().split(u';', Qt::SkipEmptyParts);
 499
 500         m_trustedReverseProxyList.clear();
 501         m_trustedReverseProxyList.reserve(proxyList.size());
 502
 503         for (QString proxy : proxyList)
 504         {
 505             if (!proxy.contains(u'/'))
 506             {
 507                 const QAbstractSocket::NetworkLayerProtocol protocol = QHostAddress(proxy).protocol();
 508                 if (protocol == QAbstractSocket::IPv4Protocol)
 509                 {
 510                     proxy.append(u"/32");
 511                 }
 512                 else if (protocol == QAbstractSocket::IPv6Protocol)
 513                 {
 514                     proxy.append(u"/128");
 515                 }
 516             }
 517
 518             const std::optional<Utils::Net::Subnet> subnet = Utils::Net::parseSubnet(proxy);
 519             if (subnet)
 520                 m_trustedReverseProxyList.push_back(subnet.value());
 521         }
 522
 523         if (m_trustedReverseProxyList.isEmpty())
 524             m_isReverseProxySupportEnabled = false;
 525     }
 526 }
 527
 528 void WebApplication::declarePublicAPI(const QString &apiPath)
 529 {
 530     m_publicAPIs << apiPath;
 531 }
 532
 533 void WebApplication::sendFile(const Path &path)
 534 {
 535     const QDateTime lastModified = Utils::Fs::lastModified(path);
 536
 537     // find translated file in cache
 538     if (!m_isAltUIUsed)
 539     {
 540         if (const auto it = m_translatedFiles.constFind(path);
 541             (it != m_translatedFiles.constEnd()) && (lastModified <= it->lastModified))
 542         {
 543             print(it->data, it->mimeType);
 544             setHeader({Http::HEADER_CACHE_CONTROL, getCachingInterval(it->mimeType)});
 545             return;
 546         }
 547     }
 548
 549     const auto readResult = Utils::IO::readFile(path, MAX_ALLOWED_FILESIZE);
 550     if (!readResult)
 551     {
 552         const QString message = tr("Web server error. %1").arg(readResult.error().message);
 553
 554         switch (readResult.error().status)
 555         {
 556         case Utils::IO::ReadError::NotExist:
 557             qDebug("%s", qUtf8Printable(message));
 558             // don't write log messages here to avoid exhausting the disk space
 559             throw NotFoundHTTPError();
 560
 561         case Utils::IO::ReadError::ExceedSize:
 562             qWarning("%s", qUtf8Printable(message));
 563             LogMsg(message, Log::WARNING);
 564             throw InternalServerErrorHTTPError(readResult.error().message);
 565
 566         case Utils::IO::ReadError::Failed:
 567         case Utils::IO::ReadError::SizeMismatch:
 568             LogMsg(message, Log::WARNING);
 569             throw InternalServerErrorHTTPError(readResult.error().message);
 570         }
 571
 572         throw InternalServerErrorHTTPError(tr("Web server error. Unknown error."));
 573     }
 574
 575     QByteArray data = readResult.value();
 576     const QMimeType mimeType = QMimeDatabase().mimeTypeForFileNameAndData(path.data(), data);
 577     const bool isTranslatable = !m_isAltUIUsed && mimeType.inherits(u"text/plain"_s);
 578
 579     if (isTranslatable)
 580     {
 581         auto dataStr = QString::fromUtf8(data);
 582         // Translate the file
 583         translateDocument(dataStr);
 584
 585         // Add the language options
 586         if (path == (m_rootFolder / Path(PRIVATE_FOLDER) / Path(u"views/preferences.html"_s)))
 587             dataStr.replace(u"${LANGUAGE_OPTIONS}"_s, createLanguagesOptionsHtml());
 588
 589         data = dataStr.toUtf8();
 590         m_translatedFiles[path] = {data, mimeType.name(), lastModified}; // caching translated file
 591     }
 592
 593     print(data, mimeType.name());
 594     setHeader({Http::HEADER_CACHE_CONTROL, getCachingInterval(mimeType.name())});
 595 }
 596
 597 Http::Response WebApplication::processRequest(const Http::Request &request, const Http::Environment &env)
 598 {
 599     m_currentSession = nullptr;
 600     m_request = request;
 601     m_env = env;
 602     m_params.clear();
 603
 604     if (m_request.method == Http::METHOD_GET)
 605     {
 606         for (auto iter = m_request.query.cbegin(); iter != m_request.query.cend(); ++iter)
 607             m_params[iter.key()] = QString::fromUtf8(iter.value());
 608     }
 609     else
 610     {
 611         m_params = m_request.posts;
 612     }
 613
 614     // clear response
 615     clear();
 616
 617     try
 618     {
 619         // block suspicious requests
 620         if ((m_isCSRFProtectionEnabled && isCrossSiteRequest(m_request))
 621             || (m_isHostHeaderValidationEnabled && !validateHostHeader(m_domainList)))
 622         {
 623             throw UnauthorizedHTTPError();
 624         }
 625
 626         // reverse proxy resolve client address
 627         m_clientAddress = resolveClientAddress();
 628
 629         sessionInitialize();
 630         doProcessRequest();
 631     }
 632     catch (const HTTPError &error)
 633     {
 634         status(error.statusCode(), error.statusText());
 635         print((!error.message().isEmpty() ? error.message() : error.statusText()), Http::CONTENT_TYPE_TXT);
 636     }
 637
 638     for (const Http::Header &prebuiltHeader : asConst(m_prebuiltHeaders))
 639         setHeader(prebuiltHeader);
 640
 641     return response();
 642 }
 643
 644 QString WebApplication::clientId() const
 645 {
 646     return m_clientAddress.toString();
 647 }
 648
 649 void WebApplication::sessionInitialize()
 650 {
 651     Q_ASSERT(!m_currentSession);
 652
 653     const QString sessionId {parseCookie(m_request.headers.value(u"cookie"_s)).value(m_sessionCookieName)};
 654
 655     // TODO: Additional session check
 656
 657     if (!sessionId.isEmpty())
 658     {
 659         m_currentSession = m_sessions.value(sessionId);
 660         if (m_currentSession)
 661         {
 662             if (m_currentSession->hasExpired(m_sessionTimeout))
 663             {
 664                 // session is outdated - removing it
 665                 delete m_sessions.take(sessionId);
 666                 m_currentSession = nullptr;
 667             }
 668             else
 669             {
 670                 m_currentSession->updateTimestamp();
 671             }
 672         }
 673         else
 674         {
 675             qDebug() << Q_FUNC_INFO << "session does not exist!";
 676         }
 677     }
 678
 679     if (!m_currentSession && !isAuthNeeded())
 680         sessionStart();
 681 }
 682
 683 QString WebApplication::generateSid() const
 684 {
 685     QString sid;
 686
 687     do
 688     {
 689         const quint32 tmp[] =
 690         {Utils::Random::rand(), Utils::Random::rand(), Utils::Random::rand()
 691                 , Utils::Random::rand(), Utils::Random::rand(), Utils::Random::rand()};
 692         sid = QString::fromLatin1(QByteArray::fromRawData(reinterpret_cast<const char *>(tmp), sizeof(tmp)).toBase64());
 693     }
 694     while (m_sessions.contains(sid));
 695
 696     return sid;
 697 }
 698
 699 bool WebApplication::isAuthNeeded()
 700 {
 701     if (!m_isLocalAuthEnabled && m_clientAddress.isLoopback())
 702         return false;
 703     if (m_isAuthSubnetWhitelistEnabled && Utils::Net::isIPInSubnets(m_clientAddress, m_authSubnetWhitelist))
 704         return false;
 705     return true;
 706 }
 707
 708 bool WebApplication::isPublicAPI(const QString &scope, const QString &action) const
 709 {
 710     return m_publicAPIs.contains(u"%1/%2"_s.arg(scope, action));
 711 }
 712
 713 void WebApplication::sessionStart()
 714 {
 715     Q_ASSERT(!m_currentSession);
 716
 717     // remove outdated sessions
 718     Algorithm::removeIf(m_sessions, [this](const QString &, const WebSession *session)
 719     {
 720         if (session->hasExpired(m_sessionTimeout))
 721         {
 722             delete session;
 723             return true;
 724         }
 725
 726         return false;
 727     });
 728
 729     m_currentSession = new WebSession(generateSid(), app());
 730     m_sessions[m_currentSession->id()] = m_currentSession;
 731
 732     m_currentSession->registerAPIController(u"app"_s, new AppController(app(), this));
 733     m_currentSession->registerAPIController(u"log"_s, new LogController(app(), this));
 734     m_currentSession->registerAPIController(u"torrentcreator"_s, new TorrentCreatorController(m_torrentCreationManager, app(), this));
 735     m_currentSession->registerAPIController(u"rss"_s, new RSSController(app(), this));
 736     m_currentSession->registerAPIController(u"search"_s, new SearchController(app(), this));
 737     m_currentSession->registerAPIController(u"torrents"_s, new TorrentsController(app(), this));
 738     m_currentSession->registerAPIController(u"transfer"_s, new TransferController(app(), this));
 739
 740     auto *syncController = new SyncController(app(), this);
 741     syncController->updateFreeDiskSpace(m_freeDiskSpaceChecker->lastResult());
 742     connect(m_freeDiskSpaceChecker, &FreeDiskSpaceChecker::checked, syncController, &SyncController::updateFreeDiskSpace);
 743     m_currentSession->registerAPIController(u"sync"_s, syncController);
 744
 745     QNetworkCookie cookie {m_sessionCookieName.toLatin1(), m_currentSession->id().toLatin1()};
 746     cookie.setHttpOnly(true);
 747     cookie.setSecure(m_isSecureCookieEnabled && isOriginTrustworthy());  // [rfc6265] 4.1.2.5. The Secure Attribute
 748     cookie.setPath(u"/"_s);
 749     if (m_isCSRFProtectionEnabled)
 750         cookie.setSameSitePolicy(QNetworkCookie::SameSite::Strict);
 751     else if (cookie.isSecure())
 752         cookie.setSameSitePolicy(QNetworkCookie::SameSite::None);
 753     setHeader({Http::HEADER_SET_COOKIE, QString::fromLatin1(cookie.toRawForm())});
 754 }
 755
 756 void WebApplication::sessionEnd()
 757 {
 758     Q_ASSERT(m_currentSession);
 759
 760     QNetworkCookie cookie {m_sessionCookieName.toLatin1()};
 761     cookie.setPath(u"/"_s);
 762     cookie.setExpirationDate(QDateTime::currentDateTime().addDays(-1));
 763
 764     delete m_sessions.take(m_currentSession->id());
 765     m_currentSession = nullptr;
 766
 767     setHeader({Http::HEADER_SET_COOKIE, QString::fromLatin1(cookie.toRawForm())});
 768 }
 769
 770 bool WebApplication::isOriginTrustworthy() const
 771 {
 772     // https://w3c.github.io/webappsec-secure-contexts/#is-origin-trustworthy
 773
 774     if (m_isReverseProxySupportEnabled)
 775     {
 776         const QString forwardedProto = request().headers.value(Http::HEADER_X_FORWARDED_PROTO);
 777         if (forwardedProto.compare(u"https", Qt::CaseInsensitive) == 0)
 778             return true;
 779     }
 780
 781     if (m_isHttpsEnabled)
 782         return true;
 783
 784     // client is on localhost
 785     if (env().clientAddress.isLoopback())
 786         return true;
 787
 788     return false;
 789 }
 790
 791 bool WebApplication::isCrossSiteRequest(const Http::Request &request) const
 792 {
 793     // https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF)_Prevention_Cheat_Sheet#Verifying_Same_Origin_with_Standard_Headers
 794
 795     const auto isSameOrigin = [](const QUrl &left, const QUrl &right) -> bool
 796     {
 797         // [rfc6454] 5. Comparing Origins
 798         return ((left.port() == right.port())
 799                 // && (left.scheme() == right.scheme())  // not present in this context
 800                 && (left.host() == right.host()));
 801     };
 802
 803     const QString targetOrigin = request.headers.value(Http::HEADER_X_FORWARDED_HOST, request.headers.value(Http::HEADER_HOST));
 804     const QString originValue = request.headers.value(Http::HEADER_ORIGIN);
 805     const QString refererValue = request.headers.value(Http::HEADER_REFERER);
 806
 807     if (originValue.isEmpty() && refererValue.isEmpty())
 808     {
 809         // owasp.org recommends to block this request, but doing so will inevitably lead Web API users to spoof headers
 810         // so lets be permissive here
 811         return false;
 812     }
 813
 814     // sent with CORS requests, as well as with POST requests
 815     if (!originValue.isEmpty())
 816     {
 817         const bool isInvalid = !isSameOrigin(urlFromHostHeader(targetOrigin), originValue);
 818         if (isInvalid)
 819         {
 820             LogMsg(tr("WebUI: Origin header & Target origin mismatch! Source IP: '%1'. Origin header: '%2'. Target origin: '%3'")
 821                    .arg(m_env.clientAddress.toString(), originValue, targetOrigin)
 822                    , Log::WARNING);
 823         }
 824         return isInvalid;
 825     }
 826
 827     if (!refererValue.isEmpty())
 828     {
 829         const bool isInvalid = !isSameOrigin(urlFromHostHeader(targetOrigin), refererValue);
 830         if (isInvalid)
 831         {
 832             LogMsg(tr("WebUI: Referer header & Target origin mismatch! Source IP: '%1'. Referer header: '%2'. Target origin: '%3'")
 833                    .arg(m_env.clientAddress.toString(), refererValue, targetOrigin)
 834                    , Log::WARNING);
 835         }
 836         return isInvalid;
 837     }
 838
 839     return true;
 840 }
 841
 842 bool WebApplication::validateHostHeader(const QStringList &domains) const
 843 {
 844     const QUrl hostHeader = urlFromHostHeader(m_request.headers[Http::HEADER_HOST]);
 845     const QString requestHost = hostHeader.host();
 846
 847     // (if present) try matching host header's port with local port
 848     const int requestPort = hostHeader.port();
 849     if ((requestPort != -1) && (m_env.localPort != requestPort))
 850     {
 851         LogMsg(tr("WebUI: Invalid Host header, port mismatch. Request source IP: '%1'. Server port: '%2'. Received Host header: '%3'")
 852                .arg(m_env.clientAddress.toString()).arg(m_env.localPort)
 853                .arg(m_request.headers[Http::HEADER_HOST])
 854                 , Log::WARNING);
 855         return false;
 856     }
 857
 858     // try matching host header with local address
 859     const bool sameAddr = m_env.localAddress.isEqual(QHostAddress(requestHost));
 860
 861     if (sameAddr)
 862         return true;
 863
 864     // try matching host header with domain list
 865     for (const auto &domain : domains)
 866     {
 867         const QRegularExpression domainRegex {Utils::String::wildcardToRegexPattern(domain), QRegularExpression::CaseInsensitiveOption};
 868         if (requestHost.contains(domainRegex))
 869             return true;
 870     }
 871
 872     LogMsg(tr("WebUI: Invalid Host header. Request source IP: '%1'. Received Host header: '%2'")
 873            .arg(m_env.clientAddress.toString(), m_request.headers[Http::HEADER_HOST])
 874             , Log::WARNING);
 875     return false;
 876 }
 877
 878 QHostAddress WebApplication::resolveClientAddress() const
 879 {
 880     if (!m_isReverseProxySupportEnabled)
 881         return m_env.clientAddress;
 882
 883     // Only reverse proxy can overwrite client address
 884     if (!Utils::Net::isIPInSubnets(m_env.clientAddress, m_trustedReverseProxyList))
 885         return m_env.clientAddress;
 886
 887     const QString forwardedFor = m_request.headers.value(Http::HEADER_X_FORWARDED_FOR);
 888
 889     if (!forwardedFor.isEmpty())
 890     {
 891         // client address is the 1st global IP in X-Forwarded-For or, if none available, the 1st IP in the list
 892         const QStringList remoteIpList = forwardedFor.split(u',', Qt::SkipEmptyParts);
 893
 894         if (!remoteIpList.isEmpty())
 895         {
 896             QHostAddress clientAddress;
 897
 898             for (const QString &remoteIp : remoteIpList)
 899             {
 900                 if (clientAddress.setAddress(remoteIp) && clientAddress.isGlobal())
 901                     return clientAddress;
 902             }
 903
 904             if (clientAddress.setAddress(remoteIpList[0]))
 905                 return clientAddress;
 906         }
 907     }
 908
 909     return m_env.clientAddress;
 910 }
 911
 912 // WebSession
 913
 914 WebSession::WebSession(const QString &sid, IApplication *app)
 915     : ApplicationComponent(app)
 916     , m_sid {sid}
 917 {
 918     updateTimestamp();
 919 }
 920
 921 QString WebSession::id() const
 922 {
 923     return m_sid;
 924 }
 925
 926 bool WebSession::hasExpired(const qint64 seconds) const
 927 {
 928     if (seconds <= 0)
 929         return false;
 930     return m_timer.hasExpired(seconds * 1000);
 931 }
 932
 933 void WebSession::updateTimestamp()
 934 {
 935     m_timer.start();
 936 }
 937
 938 void WebSession::registerAPIController(const QString &scope, APIController *controller)
 939 {
 940     Q_ASSERT(controller);
 941     m_apiControllers[scope] = controller;
 942 }
 943
 944 APIController *WebSession::getAPIController(const QString &scope) const
 945 {
 946     return m_apiControllers.value(scope);
 947 }