File indexing completed on 2024-06-23 05:13:38

 /* -*- mode: c++; c-basic-offset:4 -*-
     commands/changeroottrustcommand.cpp
 
     This file is part of Kleopatra, the KDE keymanager
     SPDX-FileCopyrightText: 2010 Klarälvdalens Datakonsult AB
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include <config-kleopatra.h>
 
 #include "changeroottrustcommand.h"
 #include "command_p.h"
 
 #include <Libkleo/Dn>
 #include <Libkleo/GnuPG>
 #include <Libkleo/KeyCache>
 
 #include "kleopatra_debug.h"
 #include <KLocalizedString>
 #include <QSaveFile>
 
 #include <QByteArray>
 #include <QDir>
 #include <QFile>
 #include <QMutex>
 #include <QMutexLocker>
 #include <QProcess>
 #include <QString>
 #include <QStringList>
 #include <QThread>
 
 #include <gpgme++/key.h>
 
 using namespace Kleo;
 using namespace Kleo::Commands;
 using namespace GpgME;
 
 class ChangeRootTrustCommand::Private : public QThread, public Command::Private
 {
     Q_OBJECT
 private:
     friend class ::Kleo::Commands::ChangeRootTrustCommand;
     ChangeRootTrustCommand *q_func() const
     {
         return static_cast<ChangeRootTrustCommand *>(q);
     }
 
 public:
     explicit Private(ChangeRootTrustCommand *qq, KeyListController *c)
         : QThread()
         , Command::Private(qq, c)
         , mutex()
         , trust(Key::Ultimate)
         , trustListFile(QDir(gnupgHomeDirectory()).absoluteFilePath(QStringLiteral("trustlist.txt")))
         , canceled(false)
     {
     }
 
 private:
     void init()
     {
         q->setWarnWhenRunningAtShutdown(false);
         connect(this, &QThread::finished, this, &ChangeRootTrustCommand::Private::slotOperationFinished);
     }
 
     void run() override;
 
 private:
     void slotOperationFinished()
     {
         KeyCache::mutableInstance()->enableFileSystemWatcher(true);
         if (error.isEmpty()) {
             KeyCache::mutableInstance()->reload(GpgME::CMS);
         } else
             Command::Private::error(i18n("Failed to update the trust database:\n"
                                          "%1",
                                          error),
                                     i18n("Root Trust Update Failed"));
         Command::Private::finished();
     }
 
 private:
     mutable QMutex mutex;
     Key::OwnerTrust trust;
     QString trustListFile;
     QString gpgConfPath;
     QString error;
     volatile bool canceled;
 };
 
 ChangeRootTrustCommand::Private *ChangeRootTrustCommand::d_func()
 {
     return static_cast<Private *>(d.get());
 }
 const ChangeRootTrustCommand::Private *ChangeRootTrustCommand::d_func() const
 {
     return static_cast<const Private *>(d.get());
 }
 
 #define q q_func()
 #define d d_func()
 
 ChangeRootTrustCommand::ChangeRootTrustCommand(KeyListController *p)
     : Command(new Private(this, p))
 {
     d->init();
 }
 
 ChangeRootTrustCommand::ChangeRootTrustCommand(QAbstractItemView *v, KeyListController *p)
     : Command(v, new Private(this, p))
 {
     d->init();
 }
 
 ChangeRootTrustCommand::ChangeRootTrustCommand(const GpgME::Key &key, KeyListController *p)
     : Command(new Private(this, p))
 {
     Q_ASSERT(!key.isNull());
     d->init();
     setKey(key);
 }
 
 ChangeRootTrustCommand::ChangeRootTrustCommand(const GpgME::Key &key, QAbstractItemView *v, KeyListController *p)
     : Command(v, new Private(this, p))
 {
     Q_ASSERT(!key.isNull());
     d->init();
     setKey(key);
 }
 
 ChangeRootTrustCommand::~ChangeRootTrustCommand()
 {
 }
 
 void ChangeRootTrustCommand::setTrust(Key::OwnerTrust trust)
 {
     Q_ASSERT(!d->isRunning());
     const QMutexLocker locker(&d->mutex);
     d->trust = trust;
 }
 
 Key::OwnerTrust ChangeRootTrustCommand::trust() const
 {
     const QMutexLocker locker(&d->mutex);
     return d->trust;
 }
 
 void ChangeRootTrustCommand::setTrustListFile(const QString &trustListFile)
 {
     Q_ASSERT(!d->isRunning());
     const QMutexLocker locker(&d->mutex);
     d->trustListFile = trustListFile;
 }
 
 QString ChangeRootTrustCommand::trustListFile() const
 {
     const QMutexLocker locker(&d->mutex);
     return d->trustListFile;
 }
 
 void ChangeRootTrustCommand::doStart()
 {
     const std::vector<Key> keys = d->keys();
     Key key;
     if (keys.size() == 1) {
         key = keys.front();
     } else {
         qCWarning(KLEOPATRA_LOG) << "can only work with one certificate at a time";
     }
 
     if (key.isNull()) {
         d->Command::Private::finished();
         return;
     }
 
     d->gpgConfPath = gpgConfPath();
     KeyCache::mutableInstance()->enableFileSystemWatcher(false);
     d->start();
 }
 
 void ChangeRootTrustCommand::doCancel()
 {
     const QMutexLocker locker(&d->mutex);
     d->canceled = true;
 }
 
 static QString change_trust_file(const QString &trustListFile, const QString &fingerprint, const DN &dn, Key::OwnerTrust trust);
 static QString run_gpgconf_reload_gpg_agent(const QString &gpgConfPath);
 
 void ChangeRootTrustCommand::Private::run()
 {
     QMutexLocker locker(&mutex);
 
     const auto key = keys().front();
     const QString fpr = QString::fromLatin1(key.primaryFingerprint());
     const auto dn = DN(key.userID(0).id());
     const Key::OwnerTrust trust = this->trust;
     const QString trustListFile = this->trustListFile;
     const QString gpgConfPath = this->gpgConfPath;
 
     locker.unlock();
 
     QString err = change_trust_file(trustListFile, fpr, dn, trust);
     if (err.isEmpty()) {
         err = run_gpgconf_reload_gpg_agent(gpgConfPath);
     }
 
     locker.relock();
 
     this->error = err;
 }
 
 static QString add_colons(const QString &fpr)
 {
     QString result;
     result.reserve(fpr.size() / 2 * 3 + 1);
     bool needColon = false;
     for (QChar ch : fpr) {
         result += ch;
         if (needColon) {
             result += QLatin1Char(':');
         }
         needColon = !needColon;
     }
     if (result.endsWith(QLatin1Char(':'))) {
         result.chop(1);
     }
     return result;
 }
 
 namespace
 {
 
 // fix stupid default-finalize behaviour...
 class KFixedSaveFile : public QSaveFile
 {
 public:
     explicit KFixedSaveFile(const QString &fileName)
         : QSaveFile(fileName)
     {
     }
     ~KFixedSaveFile() override
     {
         cancelWriting();
     }
 };
 
 }
 
 // static
 QString change_trust_file(const QString &trustListFile, const QString &key, const DN &dn, Key::OwnerTrust trust)
 {
     QList<QByteArray> trustListFileContents;
 
     if (QFile::exists(trustListFile)) { // non-existence is not fatal...
         if (QFile in(trustListFile); in.open(QIODevice::ReadOnly)) {
             trustListFileContents = in.readAll().split('\n');
             // remove last empty line to avoid adding more empty lines when we write the lines
             if (!trustListFileContents.empty() && trustListFileContents.back().isEmpty()) {
                 trustListFileContents.pop_back();
             }
         } else { // ...but failure to open an existing file _is_
             return i18n("Cannot open existing file \"%1\" for reading: %2", trustListFile, in.errorString());
         }
         // the file is now closed, so KSaveFile doesn't clobber the original
     } else {
         // the default contents of the trustlist.txt file (see the headerblurb variable in trustlist.c of gnupg);
         // we add an additional comment about the "include-default" statement
         trustListFileContents = {
             "# This is the list of trusted keys.  Comment lines, like this one, as",
             "# well as empty lines are ignored.  Lines have a length limit but this",
             "# is not a serious limitation as the format of the entries is fixed and",
             "# checked by gpg-agent.  A non-comment line starts with optional white",
             "# space, followed by the SHA-1 fingerpint in hex, followed by a flag",
             "# which may be one of 'P', 'S' or '*' and optionally followed by a list of",
             "# other flags.  The fingerprint may be prefixed with a '!' to mark the",
             "# key as not trusted.  You should give the gpg-agent a HUP or run the",
             "# command \"gpgconf --reload gpg-agent\" after changing this file.",
             "# Additionally to this file, gpg-agent will read the default trust list file",
             "# if the statement \"include-default\" is used below.",
             "",
             "",
             "# Include the default trust list",
             "include-default",
             "",
         };
     }
 
     KFixedSaveFile out(trustListFile);
     if (!out.open(QIODevice::WriteOnly))
         return i18n("Cannot open file \"%1\" for reading and writing: %2", out.fileName() /*sic!*/, out.errorString());
 
     if (!out.setPermissions(QFile::ReadOwner | QFile::WriteOwner))
         return i18n("Cannot set restrictive permissions on file %1: %2", out.fileName() /*sic!*/, out.errorString());
 
     const QString keyColon = add_colons(key);
 
     qCDebug(KLEOPATRA_LOG) << qPrintable(key) << " -> " << qPrintable(keyColon);
 
     //                                       ( 1)   (                         2                           )   (  3    )( 4)
     static const char16_t pattern[] = uR"(\s*(!?)\s*([a-fA-F0-9]{40}|(?:[a-fA-F0-9]{2}:){19}[a-fA-F0-9]{2})\s*([SsPp*])(.*))";
     static const QRegularExpression rx(QRegularExpression::anchoredPattern(pattern));
     bool found = false;
 
     for (const QByteArray &rawLine : std::as_const(trustListFileContents)) {
         const QString line = QString::fromLatin1(rawLine.data(), rawLine.size());
         const QRegularExpressionMatch match = rx.match(line);
         if (!match.hasMatch()) {
             qCDebug(KLEOPATRA_LOG) << "line \"" << rawLine.data() << "\" does not match";
             out.write(rawLine + '\n');
             continue;
         }
         const QString cap2 = match.captured(2);
         if (cap2 != key && cap2 != keyColon) {
             qCDebug(KLEOPATRA_LOG) << qPrintable(key) << " != " << qPrintable(cap2) << " != " << qPrintable(keyColon);
             out.write(rawLine + '\n');
             continue;
         }
         found = true;
         const bool disabled = match.capturedView(1) == QLatin1Char('!');
         const QByteArray flags = match.captured(3).toLatin1();
         const QByteArray rests = match.captured(4).toLatin1();
         if (trust == Key::Ultimate)
             if (!disabled) { // unchanged
                 out.write(rawLine + '\n');
             } else {
                 out.write(keyColon.toLatin1() + ' ' + flags + rests + '\n');
             }
         else if (trust == Key::Never) {
             if (disabled) { // unchanged
                 out.write(rawLine + '\n');
             } else {
                 out.write('!' + keyColon.toLatin1() + ' ' + flags + rests + '\n');
             }
         }
         // else: trust == Key::Unknown
         // -> don't write - ie.erase
     }
 
     if (!found) { // add
         out.write("\n");
         // write comment lines with DN attributes
         std::for_each(dn.begin(), dn.end(), [&out](const auto &attr) {
             out.write("# " + attr.name().toUtf8() + "=" + attr.value().toUtf8() + '\n');
         });
         if (trust == Key::Ultimate) {
             out.write(keyColon.toLatin1() + " S relax\n");
         } else if (trust == Key::Never) {
             out.write('!' + keyColon.toLatin1() + " S relax\n");
         }
     }
 
     if (!out.commit())
         return i18n("Failed to move file %1 to its final destination, %2: %3", out.fileName(), trustListFile, out.errorString());
 
     return QString();
 }
 
 // static
 QString run_gpgconf_reload_gpg_agent(const QString &gpgConfPath)
 {
     if (gpgConfPath.isEmpty()) {
         return i18n("Could not find gpgconf executable");
     }
 
     QProcess p;
     p.start(gpgConfPath, QStringList() << QStringLiteral("--reload") << QStringLiteral("gpg-agent"));
     qCDebug(KLEOPATRA_LOG) << "starting " << qPrintable(gpgConfPath) << " --reload gpg-agent";
     p.waitForFinished(-1);
     qCDebug(KLEOPATRA_LOG) << "done";
     if (p.error() == QProcess::UnknownError) {
         return QString();
     } else {
         return i18n("\"gpgconf --reload gpg-agent\" failed: %1", p.errorString());
     }
 }
 
 #undef q_func
 #undef d_func
 
 #include "changeroottrustcommand.moc"
 #include "moc_changeroottrustcommand.cpp"