src/base/http/connection.cpp

   1 /*
   2  * Bittorrent Client using Qt and libtorrent.
   3  * Copyright (C) 2018  Mike Tzou (Chocobo1)
   4  * Copyright (C) 2014  Vladimir Golovnev <glassez@yandex.ru>
   5  * Copyright (C) 2006  Ishan Arora and Christophe Dumez <chris@qbittorrent.org>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20  *
  21  * In addition, as a special exception, the copyright holders give permission to
  22  * link this program with the OpenSSL project's "OpenSSL" library (or with
  23  * modified versions of it that use the same license as the "OpenSSL" library),
  24  * and distribute the linked executables. You must obey the GNU General Public
  25  * License in all respects for all of the code used other than "OpenSSL".  If you
  26  * modify file(s), you may extend this exception to your version of the file(s),
  27  * but you are not obligated to do so. If you do not wish to do so, delete this
  28  * exception statement from your version.
  29  */
  30
  31 #include "connection.h"
  32
  33 #include <QTcpSocket>
  34
  35 #include "base/logger.h"
  36 #include "irequesthandler.h"
  37 #include "requestparser.h"
  38 #include "responsegenerator.h"
  39
  40 using namespace Http;
  41
  42 Connection::Connection(QTcpSocket *socket, IRequestHandler *requestHandler, QObject *parent)
  43     : QObject(parent)
  44     , m_socket(socket)
  45     , m_requestHandler(requestHandler)
  46 {
  47     m_socket->setParent(this);
  48
  49     // reset timer when there are activity
  50     m_idleTimer.start();
  51     connect(m_socket, &QIODevice::readyRead, this, [this]()
  52     {
  53         m_idleTimer.start();
  54         read();
  55     });
  56     connect(m_socket, &QIODevice::bytesWritten, this, [this]()
  57     {
  58         m_idleTimer.start();
  59     });
  60 }
  61
  62 Connection::~Connection()
  63 {
  64     m_socket->close();
  65 }
  66
  67 void Connection::read()
  68 {
  69     m_receivedData.append(m_socket->readAll());
  70
  71     while (!m_receivedData.isEmpty())
  72     {
  73         const RequestParser::ParseResult result = RequestParser::parse(m_receivedData);
  74
  75         switch (result.status)
  76         {
  77         case RequestParser::ParseStatus::Incomplete:
  78             {
  79                 const long bufferLimit = RequestParser::MAX_CONTENT_SIZE * 1.1;  // some margin for headers
  80                 if (m_receivedData.size() > bufferLimit)
  81                 {
  82                     LogMsg(tr("Http request size exceeds limitation, closing socket. Limit: %1, IP: %2")
  83                         .arg(bufferLimit).arg(m_socket->peerAddress().toString()), Log::WARNING);
  84
  85                     Response resp(413, u"Payload Too Large"_qs);
  86                     resp.headers[HEADER_CONNECTION] = u"close"_qs;
  87
  88                     sendResponse(resp);
  89                     m_socket->close();
  90                 }
  91             }
  92             return;
  93
  94         case RequestParser::ParseStatus::BadRequest:
  95             {
  96                 LogMsg(tr("Bad Http request, closing socket. IP: %1")
  97                     .arg(m_socket->peerAddress().toString()), Log::WARNING);
  98
  99                 Response resp(400, u"Bad Request"_qs);
 100                 resp.headers[HEADER_CONNECTION] = u"close"_qs;
 101
 102                 sendResponse(resp);
 103                 m_socket->close();
 104             }
 105             return;
 106
 107         case RequestParser::ParseStatus::OK:
 108             {
 109                 const Environment env {m_socket->localAddress(), m_socket->localPort(), m_socket->peerAddress(), m_socket->peerPort()};
 110
 111                 Response resp = m_requestHandler->processRequest(result.request, env);
 112
 113                 if (acceptsGzipEncoding(result.request.headers[u"accept-encoding"_qs]))
 114                     resp.headers[HEADER_CONTENT_ENCODING] = u"gzip"_qs;
 115
 116                 resp.headers[HEADER_CONNECTION] = u"keep-alive"_qs;
 117
 118                 sendResponse(resp);
 119                 m_receivedData = m_receivedData.mid(result.frameSize);
 120             }
 121             break;
 122
 123         default:
 124             Q_ASSERT(false);
 125             return;
 126         }
 127     }
 128 }
 129
 130 void Connection::sendResponse(const Response &response) const
 131 {
 132     m_socket->write(toByteArray(response));
 133 }
 134
 135 bool Connection::hasExpired(const qint64 timeout) const
 136 {
 137     return (m_socket->bytesAvailable() == 0)
 138         && (m_socket->bytesToWrite() == 0)
 139         && m_idleTimer.hasExpired(timeout);
 140 }
 141
 142 bool Connection::isClosed() const
 143 {
 144     return (m_socket->state() == QAbstractSocket::UnconnectedState);
 145 }
 146
 147 bool Connection::acceptsGzipEncoding(QString codings)
 148 {
 149     // [rfc7231] 5.3.4. Accept-Encoding
 150
 151     const auto isCodingAvailable = [](const QList<QStringView> &list, const QStringView encoding) -> bool
 152     {
 153         for (const QStringView &str : list)
 154         {
 155             if (!str.startsWith(encoding))
 156                 continue;
 157
 158             // without quality values
 159             if (str == encoding)
 160                 return true;
 161
 162             // [rfc7231] 5.3.1. Quality Values
 163             const QStringView substr = str.mid(encoding.size() + 3);  // ex. skip over "gzip;q="
 164
 165             bool ok = false;
 166             const double qvalue = substr.toDouble(&ok);
 167             if (!ok || (qvalue <= 0))
 168                 return false;
 169
 170             return true;
 171         }
 172         return false;
 173     };
 174
 175     const QList<QStringView> list = QStringView(codings.remove(u' ').remove(u'\t')).split(u',', Qt::SkipEmptyParts);
 176     if (list.isEmpty())
 177         return false;
 178
 179     const bool canGzip = isCodingAvailable(list, u"gzip"_qs);
 180     if (canGzip)
 181         return true;
 182
 183     const bool canAny = isCodingAvailable(list, u"*"_qs);
 184     if (canAny)
 185         return true;
 186
 187     return false;
 188 }