/* This file is part of Telegram Desktop, the official desktop application for the Telegram messaging service. For license and copyright information please follow this link: https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL */ #include "mtproto/mtproto_dc_options.h" #include "mtproto/details/mtproto_rsa_public_key.h" #include "mtproto/facade.h" #include "mtproto/connection_tcp.h" #include "storage/serialize_common.h" #include #include namespace MTP { namespace { using namespace details; struct BuiltInDc { int id; const char *ip; int port; }; const BuiltInDc kBuiltInDcs[] = { { 1, "149.154.175.50" , 443 }, { 2, "149.154.167.51" , 443 }, { 2, "95.161.76.100" , 443 }, { 3, "149.154.175.100", 443 }, { 4, "149.154.167.91" , 443 }, { 5, "149.154.171.5" , 443 }, }; const BuiltInDc kBuiltInDcsIPv6[] = { { 1, "2001:0b28:f23d:f001:0000:0000:0000:000a", 443 }, { 2, "2001:067c:04e8:f002:0000:0000:0000:000a", 443 }, { 3, "2001:0b28:f23d:f003:0000:0000:0000:000a", 443 }, { 4, "2001:067c:04e8:f004:0000:0000:0000:000a", 443 }, { 5, "2001:0b28:f23f:f005:0000:0000:0000:000a", 443 }, }; const BuiltInDc kBuiltInDcsTest[] = { { 1, "149.154.175.10" , 443 }, { 2, "149.154.167.40" , 443 }, { 3, "149.154.175.117", 443 } }; const BuiltInDc kBuiltInDcsIPv6Test[] = { { 1, "2001:0b28:f23d:f001:0000:0000:0000:000e", 443 }, { 2, "2001:067c:04e8:f002:0000:0000:0000:000e", 443 }, { 3, "2001:0b28:f23d:f003:0000:0000:0000:000e", 443 } }; const char *(kPublicRSAKeys[]) = { "\ -----BEGIN RSA PUBLIC KEY-----\n\ MIIBCgKCAQEAwVACPi9w23mF3tBkdZz+zwrzKOaaQdr01vAbU4E1pvkfj4sqDsm6\n\ lyDONS789sVoD/xCS9Y0hkkC3gtL1tSfTlgCMOOul9lcixlEKzwKENj1Yz/s7daS\n\ an9tqw3bfUV/nqgbhGX81v/+7RFAEd+RwFnK7a+XYl9sluzHRyVVaTTveB2GazTw\n\ Efzk2DWgkBluml8OREmvfraX3bkHZJTKX4EQSjBbbdJ2ZXIsRrYOXfaA+xayEGB+\n\ 8hdlLmAjbCVfaigxX0CDqWeR1yFL9kwd9P0NsZRPsmoqVwMbMu7mStFai6aIhc3n\n\ Slv8kg9qv1m6XHVQY3PnEw+QQtqSIXklHwIDAQAB\n\ -----END RSA PUBLIC KEY-----", "\ -----BEGIN PUBLIC KEY-----\n\ MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAruw2yP/BCcsJliRoW5eB\n\ VBVle9dtjJw+OYED160Wybum9SXtBBLXriwt4rROd9csv0t0OHCaTmRqBcQ0J8fx\n\ hN6/cpR1GWgOZRUAiQxoMnlt0R93LCX/j1dnVa/gVbCjdSxpbrfY2g2L4frzjJvd\n\ l84Kd9ORYjDEAyFnEA7dD556OptgLQQ2e2iVNq8NZLYTzLp5YpOdO1doK+ttrltg\n\ gTCy5SrKeLoCPPbOgGsdxJxyz5KKcZnSLj16yE5HvJQn0CNpRdENvRUXe6tBP78O\n\ 39oJ8BTHp9oIjd6XWXAsp2CvK45Ol8wFXGF710w9lwCGNbmNxNYhtIkdqfsEcwR5\n\ JwIDAQAB\n\ -----END PUBLIC KEY-----", "\ -----BEGIN PUBLIC KEY-----\n\ MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvfLHfYH2r9R70w8prHbl\n\ Wt/nDkh+XkgpflqQVcnAfSuTtO05lNPspQmL8Y2XjVT4t8cT6xAkdgfmmvnvRPOO\n\ KPi0OfJXoRVylFzAQG/j83u5K3kRLbae7fLccVhKZhY46lvsueI1hQdLgNV9n1cQ\n\ 3TDS2pQOCtovG4eDl9wacrXOJTG2990VjgnIKNA0UMoP+KF03qzryqIt3oTvZq03\n\ DyWdGK+AZjgBLaDKSnC6qD2cFY81UryRWOab8zKkWAnhw2kFpcqhI0jdV5QaSCEx\n\ vnsjVaX0Y1N0870931/5Jb9ICe4nweZ9kSDF/gip3kWLG0o8XQpChDfyvsqB9OLV\n\ /wIDAQAB\n\ -----END PUBLIC KEY-----", "\ -----BEGIN PUBLIC KEY-----\n\ MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAs/ditzm+mPND6xkhzwFI\n\ z6J/968CtkcSE/7Z2qAJiXbmZ3UDJPGrzqTDHkO30R8VeRM/Kz2f4nR05GIFiITl\n\ 4bEjvpy7xqRDspJcCFIOcyXm8abVDhF+th6knSU0yLtNKuQVP6voMrnt9MV1X92L\n\ GZQLgdHZbPQz0Z5qIpaKhdyA8DEvWWvSUwwc+yi1/gGaybwlzZwqXYoPOhwMebzK\n\ Uk0xW14htcJrRrq+PXXQbRzTMynseCoPIoke0dtCodbA3qQxQovE16q9zz4Otv2k\n\ 4j63cz53J+mhkVWAeWxVGI0lltJmWtEYK6er8VqqWot3nqmWMXogrgRLggv/Nbbo\n\ oQIDAQAB\n\ -----END PUBLIC KEY-----", "\ -----BEGIN PUBLIC KEY-----\n\ MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvmpxVY7ld/8DAjz6F6q0\n\ 5shjg8/4p6047bn6/m8yPy1RBsvIyvuDuGnP/RzPEhzXQ9UJ5Ynmh2XJZgHoE9xb\n\ nfxL5BXHplJhMtADXKM9bWB11PU1Eioc3+AXBB8QiNFBn2XI5UkO5hPhbb9mJpjA\n\ 9Uhw8EdfqJP8QetVsI/xrCEbwEXe0xvifRLJbY08/Gp66KpQvy7g8w7VB8wlgePe\n\ xW3pT13Ap6vuC+mQuJPyiHvSxjEKHgqePji9NP3tJUFQjcECqcm0yV7/2d0t/pbC\n\ m+ZH1sadZspQCEPPrtbkQBlvHb4OLiIWPGHKSMeRFvp3IWcmdJqXahxLCUS1Eh6M\n\ AQIDAQAB\n\ -----END PUBLIC KEY-----" }; } // namespace class DcOptions::WriteLocker { public: WriteLocker(not_null that) : _that(that) , _lock(&_that->_useThroughLockers) { } void unlock() { _lock.unlock(); } ~WriteLocker() { _that->computeCdnDcIds(); } private: not_null _that; QWriteLocker _lock; }; class DcOptions::ReadLocker { public: ReadLocker(not_null that) : _lock(&that->_useThroughLockers) { } void unlock() { _lock.unlock(); } private: QReadLocker _lock; }; DcOptions::DcOptions(Environment environment) : _environment(environment) { constructFromBuiltIn(); } DcOptions::DcOptions(const DcOptions &other) : _environment(other._environment) , _data(other._data) , _cdnDcIds(other._cdnDcIds) , _publicKeys(other._publicKeys) , _cdnPublicKeys(other._cdnPublicKeys) , _immutable(other._immutable) { } DcOptions::~DcOptions() = default; bool DcOptions::ValidateSecret(bytes::const_span secret) { // See also TcpConnection::Protocol::Create. return (secret.size() >= 21 && secret[0] == bytes::type(0xEE)) || (secret.size() == 17 && secret[0] == bytes::type(0xDD)) || (secret.size() == 16) || secret.empty(); } void DcOptions::readBuiltInPublicKeys() { for (const auto key : kPublicRSAKeys) { const auto keyBytes = bytes::make_span(key, strlen(key)); auto parsed = RSAPublicKey(keyBytes); if (parsed.valid()) { _publicKeys.emplace(parsed.fingerprint(), std::move(parsed)); } else { LOG(("MTP Error: could not read this public RSA key:")); LOG((key)); } } } Environment DcOptions::environment() const { return _environment; } bool DcOptions::isTestMode() const { return (_environment != Environment::Production); } void DcOptions::constructFromBuiltIn() { WriteLocker lock(this); _data.clear(); readBuiltInPublicKeys(); const auto list = isTestMode() ? gsl::make_span(kBuiltInDcsTest) : gsl::make_span(kBuiltInDcs).subspan(0); for (const auto &entry : list) { const auto flags = Flag::f_static | 0; applyOneGuarded(entry.id, flags, entry.ip, entry.port, {}); DEBUG_LOG(("MTP Info: adding built in DC %1 connect option: %2:%3" ).arg(entry.id ).arg(entry.ip ).arg(entry.port)); } const auto listv6 = isTestMode() ? gsl::make_span(kBuiltInDcsIPv6Test) : gsl::make_span(kBuiltInDcsIPv6).subspan(0); for (const auto &entry : listv6) { const auto flags = Flag::f_static | Flag::f_ipv6; applyOneGuarded(entry.id, flags, entry.ip, entry.port, {}); DEBUG_LOG(("MTP Info: adding built in DC %1 IPv6 connect option: " "%2:%3" ).arg(entry.id ).arg(entry.ip ).arg(entry.port)); } } void DcOptions::processFromList( const QVector &options, bool overwrite) { if (options.empty() || _immutable) { return; } auto data = [&] { if (overwrite) { return base::flat_map>(); } ReadLocker lock(this); return _data; }(); for (auto &mtpOption : options) { if (mtpOption.type() != mtpc_dcOption) { LOG(("Wrong type in DcOptions: %1").arg(mtpOption.type())); continue; } auto &option = mtpOption.c_dcOption(); auto dcId = option.vid().v; auto flags = option.vflags().v; auto ip = std::string( option.vip_address().v.constData(), option.vip_address().v.size()); auto port = option.vport().v; auto secret = bytes::make_vector(option.vsecret().value_or_empty()); ApplyOneOption(data, dcId, flags, ip, port, secret); } const auto difference = [&] { WriteLocker lock(this); auto result = CountOptionsDifference(_data, data); if (!result.empty()) { _data = std::move(data); } return result; }(); for (const auto dcId : difference) { _changed.fire_copy(dcId); } } void DcOptions::setFromList(const MTPVector &options) { processFromList(options.v, true); } void DcOptions::addFromList(const MTPVector &options) { processFromList(options.v, false); } void DcOptions::addFromOther(DcOptions &&options) { if (this == &options || _immutable) { return; } auto idsChanged = std::vector(); { ReadLocker lock(&options); if (options._data.empty()) { return; } idsChanged.reserve(options._data.size()); { WriteLocker lock(this); const auto changed = [&](const std::vector &list) { auto result = false; for (const auto &endpoint : list) { const auto dcId = endpoint.id; const auto flags = endpoint.flags; const auto &ip = endpoint.ip; const auto port = endpoint.port; const auto &secret = endpoint.secret; if (applyOneGuarded(dcId, flags, ip, port, secret)) { result = true; } } return result; }; for (const auto &item : base::take(options._data)) { if (changed(item.second)) { idsChanged.push_back(item.first); } } for (auto &item : options._cdnPublicKeys) { for (auto &entry : item.second) { _cdnPublicKeys[item.first].insert(std::move(entry)); } } } } for (const auto dcId : idsChanged) { _changed.fire_copy(dcId); } } void DcOptions::constructAddOne( int id, Flags flags, const std::string &ip, int port, const bytes::vector &secret) { WriteLocker lock(this); applyOneGuarded(BareDcId(id), flags, ip, port, secret); } bool DcOptions::applyOneGuarded( DcId dcId, Flags flags, const std::string &ip, int port, const bytes::vector &secret) { return ApplyOneOption(_data, dcId, flags, ip, port, secret); } bool DcOptions::ApplyOneOption( base::flat_map> &data, DcId dcId, Flags flags, const std::string &ip, int port, const bytes::vector &secret) { auto i = data.find(dcId); if (i != data.cend()) { for (auto &endpoint : i->second) { if (endpoint.ip == ip && endpoint.port == port) { return false; } } i->second.emplace_back(dcId, flags, ip, port, secret); } else { data.emplace(dcId, std::vector( 1, Endpoint(dcId, flags, ip, port, secret))); } return true; } std::vector DcOptions::CountOptionsDifference( const base::flat_map> &a, const base::flat_map> &b) { auto result = std::vector(); const auto find = []( const std::vector &where, const Endpoint &what) { for (const auto &endpoint : where) { if (endpoint.ip == what.ip && endpoint.port == what.port) { return true; } } return false; }; const auto equal = [&]( const std::vector &m, const std::vector &n) { if (m.size() != n.size()) { return false; } for (const auto &endpoint : m) { if (!find(n, endpoint)) { return false; } } return true; }; auto i = begin(a); auto j = begin(b); const auto max = std::numeric_limits::max(); while (i != end(a) || j != end(b)) { const auto aId = (i == end(a)) ? max : i->first; const auto bId = (j == end(b)) ? max : j->first; if (aId < bId) { result.push_back(aId); ++i; } else if (bId < aId) { result.push_back(bId); ++j; } else { if (!equal(i->second, j->second)) { result.push_back(aId); } ++i; ++j; } } return result; } QByteArray DcOptions::serialize() const { if (_immutable) { // Don't write the overriden options to our settings. return DcOptions(_environment).serialize(); } ReadLocker lock(this); auto size = sizeof(qint32); // Dc options. auto optionsCount = 0; size += sizeof(qint32); for (const auto &item : _data) { if (isTemporaryDcId(item.first)) { continue; } for (const auto &endpoint : item.second) { ++optionsCount; // id + flags + port size += sizeof(qint32) + sizeof(qint32) + sizeof(qint32); size += sizeof(qint32) + endpoint.ip.size(); size += sizeof(qint32) + endpoint.secret.size(); } } // CDN public keys. auto count = 0; for (auto &keysInDc : _cdnPublicKeys) { count += keysInDc.second.size(); } struct SerializedPublicKey { DcId dcId; bytes::vector n; bytes::vector e; }; std::vector publicKeys; publicKeys.reserve(count); size += sizeof(qint32); for (const auto &keysInDc : _cdnPublicKeys) { for (const auto &entry : keysInDc.second) { publicKeys.push_back({ keysInDc.first, entry.second.getN(), entry.second.getE() }); size += sizeof(qint32) + Serialize::bytesSize(publicKeys.back().n) + Serialize::bytesSize(publicKeys.back().e); } } constexpr auto kVersion = 1; auto result = QByteArray(); result.reserve(size); { QDataStream stream(&result, QIODevice::WriteOnly); stream.setVersion(QDataStream::Qt_5_1); stream << qint32(-kVersion); // Dc options. stream << qint32(optionsCount); for (const auto &item : _data) { if (isTemporaryDcId(item.first)) { continue; } for (const auto &endpoint : item.second) { stream << qint32(endpoint.id) << qint32(endpoint.flags) << qint32(endpoint.port) << qint32(endpoint.ip.size()); stream.writeRawData(endpoint.ip.data(), endpoint.ip.size()); stream << qint32(endpoint.secret.size()); stream.writeRawData( reinterpret_cast(endpoint.secret.data()), endpoint.secret.size()); } } // CDN public keys. stream << qint32(publicKeys.size()); for (auto &key : publicKeys) { stream << qint32(key.dcId) << Serialize::bytes(key.n) << Serialize::bytes(key.e); } } return result; } bool DcOptions::constructFromSerialized(const QByteArray &serialized) { QDataStream stream(serialized); stream.setVersion(QDataStream::Qt_5_1); auto minusVersion = qint32(0); stream >> minusVersion; const auto version = (minusVersion < 0) ? (-minusVersion) : 0; auto count = qint32(0); if (version > 0) { stream >> count; } else { count = minusVersion; } if (stream.status() != QDataStream::Ok) { LOG(("MTP Error: Bad data for DcOptions::constructFromSerialized()")); return false; } WriteLocker lock(this); _data.clear(); for (auto i = 0; i != count; ++i) { qint32 id = 0, flags = 0, port = 0, ipSize = 0; stream >> id >> flags >> port >> ipSize; // https://stackoverflow.com/questions/1076714/max-length-for-client-ip-address constexpr auto kMaxIpSize = 45; if (ipSize <= 0 || ipSize > kMaxIpSize) { LOG(("MTP Error: Bad data inside DcOptions::constructFromSerialized()")); return false; } auto ip = std::string(ipSize, ' '); stream.readRawData(ip.data(), ipSize); constexpr auto kMaxSecretSize = 32; auto secret = bytes::vector(); if (version > 0) { auto secretSize = qint32(0); stream >> secretSize; if (secretSize < 0 || secretSize > kMaxSecretSize) { LOG(("MTP Error: Bad data inside DcOptions::constructFromSerialized()")); return false; } else if (secretSize > 0) { secret.resize(secretSize); stream.readRawData( reinterpret_cast(secret.data()), secretSize); } } if (stream.status() != QDataStream::Ok) { LOG(("MTP Error: Bad data inside DcOptions::constructFromSerialized()")); return false; } applyOneGuarded( DcId(id), Flags::from_raw(flags), ip, port, secret); } // Read CDN config if (!stream.atEnd()) { auto count = qint32(0); stream >> count; if (stream.status() != QDataStream::Ok) { LOG(("MTP Error: Bad data for CDN config in DcOptions::constructFromSerialized()")); return false; } for (auto i = 0; i != count; ++i) { qint32 dcId = 0; bytes::vector n, e; stream >> dcId >> Serialize::bytes(n) >> Serialize::bytes(e); if (stream.status() != QDataStream::Ok) { LOG(("MTP Error: Bad data for CDN config inside DcOptions::constructFromSerialized()")); return false; } auto key = RSAPublicKey(n, e); if (key.valid()) { _cdnPublicKeys[dcId].emplace(key.fingerprint(), std::move(key)); } else { LOG(("MTP Error: Could not read valid CDN public key.")); return false; } } } return true; } rpl::producer DcOptions::changed() const { return _changed.events(); } rpl::producer<> DcOptions::cdnConfigChanged() const { return _cdnConfigChanged.events(); } std::vector DcOptions::configEnumDcIds() const { auto result = std::vector(); { ReadLocker lock(this); result.reserve(_data.size()); for (auto &item : _data) { const auto dcId = item.first; Assert(!item.second.empty()); if (!isCdnDc(item.second.front().flags) && !isTemporaryDcId(dcId)) { result.push_back(dcId); } } } ranges::sort(result); return result; } DcType DcOptions::dcType(ShiftedDcId shiftedDcId) const { if (isTemporaryDcId(shiftedDcId)) { return DcType::Temporary; } ReadLocker lock(this); if (_cdnDcIds.find(BareDcId(shiftedDcId)) != _cdnDcIds.cend()) { return DcType::Cdn; } const auto dcId = BareDcId(shiftedDcId); if (isDownloadDcId(shiftedDcId) && hasMediaOnlyOptionsFor(dcId)) { return DcType::MediaCluster; } return DcType::Regular; } void DcOptions::setCDNConfig(const MTPDcdnConfig &config) { WriteLocker lock(this); _cdnPublicKeys.clear(); for (const auto &key : config.vpublic_keys().v) { key.match([&](const MTPDcdnPublicKey &data) { const auto keyBytes = bytes::make_span(data.vpublic_key().v); auto key = RSAPublicKey(keyBytes); if (key.valid()) { _cdnPublicKeys[data.vdc_id().v].emplace( key.fingerprint(), std::move(key)); } else { LOG(("MTP Error: could not read this public RSA key:")); LOG((qs(data.vpublic_key()))); } }); } lock.unlock(); _cdnConfigChanged.fire({}); } bool DcOptions::hasCDNKeysForDc(DcId dcId) const { ReadLocker lock(this); return _cdnPublicKeys.find(dcId) != _cdnPublicKeys.cend(); } RSAPublicKey DcOptions::getDcRSAKey( DcId dcId, const QVector &fingerprints) const { const auto findKey = [&]( const base::flat_map &keys) { for (const auto &fingerprint : fingerprints) { const auto it = keys.find(static_cast(fingerprint.v)); if (it != keys.cend()) { return it->second; } } return RSAPublicKey(); }; { ReadLocker lock(this); const auto it = _cdnPublicKeys.find(dcId); if (it != _cdnPublicKeys.cend()) { return findKey(it->second); } } return findKey(_publicKeys); } auto DcOptions::lookup( DcId dcId, DcType type, bool throughProxy) const -> Variants { using Flag = Flag; auto result = Variants(); ReadLocker lock(this); const auto i = _data.find(dcId); if (i == end(_data)) { return result; } for (const auto &endpoint : i->second) { const auto flags = endpoint.flags; if (type == DcType::Cdn && !(flags & Flag::f_cdn)) { continue; } else if (type != DcType::MediaCluster && (flags & Flag::f_media_only)) { continue; } else if (!ValidateSecret(endpoint.secret)) { continue; } const auto address = (flags & Flag::f_ipv6) ? Variants::IPv6 : Variants::IPv4; result.data[address][Variants::Tcp].push_back(endpoint); if (!(flags & (Flag::f_tcpo_only | Flag::f_secret))) { result.data[address][Variants::Http].push_back(endpoint); } } if (type == DcType::MediaCluster) { FilterIfHasWithFlag(result, Flag::f_media_only); } if (throughProxy) { FilterIfHasWithFlag(result, Flag::f_static); } return result; } bool DcOptions::hasMediaOnlyOptionsFor(DcId dcId) const { ReadLocker lock(this); const auto i = _data.find(dcId); if (i == end(_data)) { return false; } for (const auto &endpoint : i->second) { const auto flags = endpoint.flags; if (flags & Flag::f_media_only) { return true; } } return false; } void DcOptions::FilterIfHasWithFlag(Variants &variants, Flag flag) { const auto is = [&](const Endpoint &endpoint) { return (endpoint.flags & flag) != 0; }; const auto has = [&](const std::vector &list) { return ranges::any_of(list, is); }; for (auto &byAddress : variants.data) { for (auto &list : byAddress) { if (has(list)) { list = ranges::view::all( list ) | ranges::view::filter( is ) | ranges::to_vector; } } } } void DcOptions::computeCdnDcIds() { _cdnDcIds.clear(); for (auto &item : _data) { Assert(!item.second.empty()); if (item.second.front().flags & Flag::f_cdn) { _cdnDcIds.insert(BareDcId(item.first)); } } } bool DcOptions::loadFromFile(const QString &path) { QVector options; QFile f(path); if (!f.open(QIODevice::ReadOnly)) { LOG(("MTP Error: could not read '%1'").arg(path)); return false; } QTextStream stream(&f); stream.setCodec("UTF-8"); while (!stream.atEnd()) { auto line = stream.readLine(); auto components = line.split(QRegularExpression(R"(\s)"), QString::SkipEmptyParts); if (components.isEmpty() || components[0].startsWith('#')) { continue; } auto error = [line] { LOG(("MTP Error: in .tdesktop-endpoints expected 'dcId host port [tcpo_only] [media_only]', got '%1'").arg(line)); return false; }; if (components.size() < 3) { return error(); } auto dcId = components[0].toInt(); auto ip = components[1]; auto port = components[2].toInt(); auto host = QHostAddress(); if (dcId <= 0 || dcId >= kDcShift || !host.setAddress(ip) || port <= 0) { return error(); } auto flags = Flags(0); if (host.protocol() == QAbstractSocket::IPv6Protocol) { flags |= Flag::f_ipv6; } for (auto &option : components.mid(3)) { if (option.startsWith('#')) { break; } else if (option == qstr("tcpo_only")) { flags |= Flag::f_tcpo_only; } else if (option == qstr("media_only")) { flags |= Flag::f_media_only; } else { return error(); } } options.push_back(MTP_dcOption( MTP_flags(flags), MTP_int(dcId), MTP_string(ip), MTP_int(port), MTPbytes())); } if (options.isEmpty()) { LOG(("MTP Error: in .tdesktop-endpoints expected at least one endpoint being provided.")); return false; } _immutable = false; setFromList(MTP_vector(options)); _immutable = true; return true; } bool DcOptions::writeToFile(const QString &path) const { QFile f(path); if (!f.open(QIODevice::WriteOnly)) { return false; } QTextStream stream(&f); stream.setCodec("UTF-8"); ReadLocker lock(this); for (const auto &item : _data) { for (const auto &option : item.second) { stream << option.id << ' ' << QString::fromStdString(option.ip) << ' ' << option.port; if (option.flags & Flag::f_tcpo_only) { stream << " tcpo_only"; } if (option.flags & Flag::f_media_only) { stream << " media_only"; } stream << '\n'; } } return true; } } // namespace MTP