src/base/bittorrent/magneturi.cpp

   1 /*
   2  * Bittorrent Client using Qt and libtorrent.
   3  * Copyright (C) 2015  Vladimir Golovnev <glassez@yandex.ru>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  18  *
  19  * In addition, as a special exception, the copyright holders give permission to
  20  * link this program with the OpenSSL project's "OpenSSL" library (or with
  21  * modified versions of it that use the same license as the "OpenSSL" library),
  22  * and distribute the linked executables. You must obey the GNU General Public
  23  * License in all respects for all of the code used other than "OpenSSL".  If you
  24  * modify file(s), you may extend this exception to your version of the file(s),
  25  * but you are not obligated to do so. If you do not wish to do so, delete this
  26  * exception statement from your version.
  27  */
  28
  29 #include "magneturi.h"
  30
  31 #include <libtorrent/bencode.hpp>
  32 #include <libtorrent/error_code.hpp>
  33 #include <libtorrent/magnet_uri.hpp>
  34 #include <libtorrent/sha1_hash.hpp>
  35
  36 #include <QRegularExpression>
  37
  38 #include "base/global.h"
  39 #include "infohash.h"
  40
  41 namespace
  42 {
  43     // BEP9 Extension for Peers to Send Metadata Files
  44
  45     bool isV1Hash(const QString &string)
  46     {
  47         // There are 2 representations for BitTorrent v1 info hash:
  48         // 1. 40 chars hex-encoded string
  49         //      == 20 (SHA-1 length in bytes) * 2 (each byte maps to 2 hex characters)
  50         // 2. 32 chars Base32 encoded string
  51         //      == 20 (SHA-1 length in bytes) * 1.6 (the efficiency of Base32 encoding)
  52         const int V1_HEX_SIZE = SHA1Hash::length() * 2;
  53         const int V1_BASE32_SIZE = SHA1Hash::length() * 1.6;
  54
  55         return ((((string.size() == V1_HEX_SIZE))
  56                 && !string.contains(QRegularExpression(u"[^0-9A-Fa-f]"_s)))
  57             || ((string.size() == V1_BASE32_SIZE)
  58                 && !string.contains(QRegularExpression(u"[^2-7A-Za-z]"_s))));
  59     }
  60
  61     bool isV2Hash(const QString &string)
  62     {
  63         // There are 1 representation for BitTorrent v2 info hash:
  64         // 1. 64 chars hex-encoded string
  65         //      == 32 (SHA-2 256 length in bytes) * 2 (each byte maps to 2 hex characters)
  66         const int V2_HEX_SIZE = SHA256Hash::length() * 2;
  67
  68         return (string.size() == V2_HEX_SIZE)
  69                 && !string.contains(QRegularExpression(u"[^0-9A-Fa-f]"_s));
  70     }
  71 }
  72
  73 using namespace BitTorrent;
  74
  75 const int magnetUriId = qRegisterMetaType<MagnetUri>();
  76
  77 MagnetUri::MagnetUri(const QString &source)
  78     : m_url(source)
  79 {
  80     if (source.isEmpty()) return;
  81
  82     if (isV2Hash(source))
  83         m_url = u"magnet:?xt=urn:btmh:1220" + source; // 0x12 0x20 is the "multihash format" tag for the SHA-256 hashing scheme.
  84     else if (isV1Hash(source))
  85         m_url = u"magnet:?xt=urn:btih:" + source;
  86
  87     lt::error_code ec;
  88     lt::parse_magnet_uri(m_url.toStdString(), m_addTorrentParams, ec);
  89     if (ec) return;
  90
  91     m_valid = true;
  92
  93 #ifdef QBT_USES_LIBTORRENT2
  94     m_infoHash = m_addTorrentParams.info_hashes;
  95 #else
  96     m_infoHash = m_addTorrentParams.info_hash;
  97 #endif
  98
  99     m_name = QString::fromStdString(m_addTorrentParams.name);
 100
 101     m_trackers.reserve(static_cast<decltype(m_trackers)::size_type>(m_addTorrentParams.trackers.size()));
 102     int tier = 0;
 103     auto tierIter = m_addTorrentParams.tracker_tiers.cbegin();
 104     for (const std::string &url : m_addTorrentParams.trackers)
 105     {
 106         if (tierIter != m_addTorrentParams.tracker_tiers.cend())
 107             tier = *tierIter++;
 108
 109         m_trackers.append({QString::fromStdString(url), tier});
 110     }
 111
 112     m_urlSeeds.reserve(static_cast<decltype(m_urlSeeds)::size_type>(m_addTorrentParams.url_seeds.size()));
 113     for (const std::string &urlSeed : m_addTorrentParams.url_seeds)
 114         m_urlSeeds.append(QString::fromStdString(urlSeed));
 115 }
 116
 117 bool MagnetUri::isValid() const
 118 {
 119     return m_valid;
 120 }
 121
 122 InfoHash MagnetUri::infoHash() const
 123 {
 124     return m_infoHash;
 125 }
 126
 127 QString MagnetUri::name() const
 128 {
 129     return m_name;
 130 }
 131
 132 QVector<TrackerEntry> MagnetUri::trackers() const
 133 {
 134     return m_trackers;
 135 }
 136
 137 QVector<QUrl> MagnetUri::urlSeeds() const
 138 {
 139     return m_urlSeeds;
 140 }
 141
 142 QString MagnetUri::url() const
 143 {
 144     return m_url;
 145 }
 146
 147 lt::add_torrent_params MagnetUri::addTorrentParams() const
 148 {
 149     return m_addTorrentParams;
 150 }