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