src/base/utils/net.cpp

   1 /*
   2  * Bittorrent Client using Qt and libtorrent.
   3  * Copyright (C) 2016  Alexandr Milovantsev <dzmat@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 "net.h"
  30
  31 #include <QList>
  32 #include <QNetworkInterface>
  33 #include <QPair>
  34 #include <QSslCertificate>
  35 #include <QSslKey>
  36 #include <QString>
  37 #include <QVector>
  38
  39 #include "base/global.h"
  40
  41 namespace Utils
  42 {
  43     namespace Net
  44     {
  45         bool isValidIP(const QString &ip)
  46         {
  47             return !QHostAddress(ip).isNull();
  48         }
  49
  50         std::optional<Subnet> parseSubnet(const QString &subnetStr)
  51         {
  52             const Subnet subnet = QHostAddress::parseSubnet(subnetStr);
  53             const Subnet invalid = {QHostAddress(), -1};
  54             if (subnet == invalid)
  55                 return std::nullopt;
  56             return subnet;
  57         }
  58
  59         bool isLoopbackAddress(const QHostAddress &addr)
  60         {
  61             return (addr == QHostAddress::LocalHost)
  62                     || (addr == QHostAddress::LocalHostIPv6)
  63                     || (addr == QHostAddress(u"::ffff:127.0.0.1"_s));
  64         }
  65
  66         bool isIPInSubnets(const QHostAddress &addr, const QVector<Subnet> &subnets)
  67         {
  68             QHostAddress protocolEquivalentAddress;
  69             bool addrConversionOk = false;
  70
  71             if (addr.protocol() == QAbstractSocket::IPv4Protocol)
  72             {
  73                 // always succeeds
  74                 protocolEquivalentAddress = QHostAddress(addr.toIPv6Address());
  75                 addrConversionOk = true;
  76             }
  77             else
  78             {
  79                 // only succeeds when addr is an ipv4-mapped ipv6 address
  80                 protocolEquivalentAddress = QHostAddress(addr.toIPv4Address(&addrConversionOk));
  81             }
  82
  83             return std::any_of(subnets.begin(), subnets.end(), [&](const Subnet &subnet)
  84             {
  85                 return addr.isInSubnet(subnet)
  86                     || (addrConversionOk && protocolEquivalentAddress.isInSubnet(subnet));
  87             });
  88         }
  89
  90         QString subnetToString(const Subnet &subnet)
  91         {
  92             return subnet.first.toString() + u'/' + QString::number(subnet.second);
  93         }
  94
  95         QHostAddress canonicalIPv6Addr(const QHostAddress &addr)
  96         {
  97             // Link-local IPv6 textual address always contains a scope id (or zone index)
  98             // The scope id is appended to the IPv6 address using the '%' character
  99             // The scope id can be either a interface name or an interface number
 100             // Examples:
 101             // fe80::1%ethernet_17
 102             // fe80::1%13
 103             // The interface number is the mandatory supported way
 104             // Unfortunately for us QHostAddress::toString() outputs (at least on Windows)
 105             // the interface name, and libtorrent/boost.asio only support an interface number
 106             // as scope id. Furthermore, QHostAddress doesn't have any convenient method to
 107             // affect this, so we jump through hoops here.
 108             if (addr.protocol() != QAbstractSocket::IPv6Protocol)
 109                 return QHostAddress{addr.toIPv6Address()};
 110
 111             // QHostAddress::setScopeId(addr.scopeId()); // Even though the docs say that setScopeId
 112             // will convert a name to a number, this doesn't happen. Probably a Qt bug.
 113             const QString scopeIdTxt = addr.scopeId();
 114             if (scopeIdTxt.isEmpty())
 115                 return addr;
 116
 117             const int id = QNetworkInterface::interfaceIndexFromName(scopeIdTxt);
 118             if (id == 0) // This failure might mean that the scope id was already a number
 119                 return addr;
 120
 121             QHostAddress canonical(addr.toIPv6Address());
 122             canonical.setScopeId(QString::number(id));
 123             return canonical;
 124         }
 125
 126         QList<QSslCertificate> loadSSLCertificate(const QByteArray &data)
 127         {
 128             const QList<QSslCertificate> certs {QSslCertificate::fromData(data)};
 129             const bool hasInvalidCerts = std::any_of(certs.cbegin(), certs.cend(), [](const QSslCertificate &cert)
 130             {
 131                 return cert.isNull();
 132             });
 133             return hasInvalidCerts ? QList<QSslCertificate>() : certs;
 134         }
 135
 136         bool isSSLCertificatesValid(const QByteArray &data)
 137         {
 138             return !loadSSLCertificate(data).isEmpty();
 139         }
 140
 141         QSslKey loadSSLKey(const QByteArray &data)
 142         {
 143             // try different formats
 144             const QSslKey key {data, QSsl::Rsa};
 145             if (!key.isNull())
 146                 return key;
 147             return {data, QSsl::Ec};
 148         }
 149
 150         bool isSSLKeyValid(const QByteArray &data)
 151         {
 152             return !loadSSLKey(data).isNull();
 153         }
 154     }
 155 }