qt: Support decryption (with verification) directly to/from files

* lang/qt/src/Makefile.am: Add new files.
* lang/qt/src/job.cpp (DecryptVerifyJob): Move definition of constructor
and destructor and inclusion of the moc file to the corresponding .cpp
file.
* lang/qt/src/decryptverifyjob.cpp: New.
* lang/qt/src/decryptverifyjob.h (DecryptVerifyJob): Add member
functions setInputFile, inputFile, setOutputFile, outputFile.
* lang/qt/src/decryptverifyjob_p.h: New.
* lang/qt/src/qgpgmedecryptverifyjob.cpp (class
QGpgMEDecryptVerifyJobPrivate): New.
(QGpgMEDecryptVerifyJob::QGpgMEDecryptVerifyJob): Instantiate private
job class.
(decrypt_verify_from_filename): New.

* lang/qt/tests/Makefile.am: Add new test program.
* lang/qt/tests/run-decryptverifyjob.cpp: New.
--

This makes it possible to tell gpg to read the input and write the
output directly to a specified file bypassing GpgME's Data IO when
decrypting (and verifying) a file.

GnuPG-bug-id: 6550

lang/qt/src/Makefile.am

@@ -36,6 +36,7 @@ qgpgme_sources = \
     dataprovider.cpp \
     debug.cpp \
     decryptverifyarchivejob.cpp \
+    decryptverifyjob.cpp \
     encryptarchivejob.cpp \
     filelistdataprovider.cpp \
     job.cpp multideletejob.cpp qgpgmeadduseridjob.cpp \
@@ -180,6 +181,7 @@ private_qgpgme_headers = \
     changeexpiryjob_p.h \
     cleaner.h \
     decryptverifyarchivejob_p.h \
+    decryptverifyjob_p.h \
     encryptarchivejob_p.h \
     encryptjob_p.h \
     importjob_p.h \

lang/qt/src/decryptverifyjob.cpp

@@ -0,0 +1,74 @@
+/*
+    decryptverifyjob.cpp
+
+    This file is part of qgpgme, the Qt API binding for gpgme
+    Copyright (c) 2023 g10 Code GmbH
+    Software engineering by Ingo Klöcker <dev@ingo-kloecker.de>
+
+    QGpgME is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License as
+    published by the Free Software Foundation; either version 2 of the
+    License, or (at your option) any later version.
+
+    QGpgME is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+    In addition, as a special exception, the copyright holders give
+    permission to link the code of this program with any edition of
+    the Qt library by Trolltech AS, Norway (or with modified versions
+    of Qt that use the same license as Qt), and distribute linked
+    combinations including the two.  You must obey the GNU General
+    Public License in all respects for all of the code used other than
+    Qt.  If you modify this file, you may extend this exception to
+    your version of the file, but you are not obligated to do so.  If
+    you do not wish to do so, delete this exception statement from
+    your version.
+*/
+
+#ifdef HAVE_CONFIG_H
+ #include "config.h"
+#endif
+
+#include "decryptverifyjob.h"
+#include "decryptverifyjob_p.h"
+
+using namespace QGpgME;
+
+DecryptVerifyJob::DecryptVerifyJob(QObject *parent)
+    : Job{parent}
+{
+}
+
+DecryptVerifyJob::~DecryptVerifyJob() = default;
+
+void DecryptVerifyJob::setInputFile(const QString &path)
+{
+    auto d = jobPrivate<DecryptVerifyJobPrivate>(this);
+    d->m_inputFilePath = path;
+}
+
+QString DecryptVerifyJob::inputFile() const
+{
+    auto d = jobPrivate<DecryptVerifyJobPrivate>(this);
+    return d->m_inputFilePath;
+}
+
+void DecryptVerifyJob::setOutputFile(const QString &path)
+{
+    auto d = jobPrivate<DecryptVerifyJobPrivate>(this);
+    d->m_outputFilePath = path;
+}
+
+QString DecryptVerifyJob::outputFile() const
+{
+    auto d = jobPrivate<DecryptVerifyJobPrivate>(this);
+    return d->m_outputFilePath;
+}
+
+#include "decryptverifyjob.moc"

lang/qt/src/decryptverifyjob.h

@@ -62,6 +62,14 @@ namespace QGpgME
    DecryptVerifyJob instance will have scheduled it's own destruction with
    a call to QObject::deleteLater().
 
+   Alternatively, the job can be started with startIt() after setting
+   an input file and an output file. If the job is started this way then
+   the backend reads the input and writes the output directly from/to the
+   specified input file and output file. In this case the plainText value of
+   the result signal will always be empty. This direct IO mode is currently
+   only supported for OpenPGP. Note that startIt() does not schedule the job's
+   destruction if starting the job failed.
+
    After result() is emitted, the DecryptVerifyJob will schedule it's own
    destruction by calling QObject::deleteLater().
 */
@@ -71,7 +79,27 @@ class QGPGME_EXPORT DecryptVerifyJob : public Job
 protected:
     explicit DecryptVerifyJob(QObject *parent);
 public:
-    ~DecryptVerifyJob();
+    ~DecryptVerifyJob() override;
+
+    /**
+     * Sets the path of the file to decrypt (and verify).
+     *
+     * Used if the job is started with startIt().
+     */
+    void setInputFile(const QString &path);
+    QString inputFile() const;
+
+    /**
+     * Sets the path of the file to write the result to.
+     *
+     * Used if the job is started with startIt().
+     *
+     * \note If a file with this path exists, then the job will fail, i.e. you
+     * need to delete an existing file that shall be overwritten before you
+     * start the job.
+     */
+    void setOutputFile(const QString &path);
+    QString outputFile() const;
 
     /**
        Starts the combined decryption and verification operation.

lang/qt/src/decryptverifyjob_p.h

@@ -0,0 +1,50 @@
+/*
+    decryptverifyjob_p.h
+
+    This file is part of qgpgme, the Qt API binding for gpgme
+    Copyright (c) 2023 g10 Code GmbH
+    Software engineering by Ingo Klöcker <dev@ingo-kloecker.de>
+
+    QGpgME is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License as
+    published by the Free Software Foundation; either version 2 of the
+    License, or (at your option) any later version.
+
+    QGpgME is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+    In addition, as a special exception, the copyright holders give
+    permission to link the code of this program with any edition of
+    the Qt library by Trolltech AS, Norway (or with modified versions
+    of Qt that use the same license as Qt), and distribute linked
+    combinations including the two.  You must obey the GNU General
+    Public License in all respects for all of the code used other than
+    Qt.  If you modify this file, you may extend this exception to
+    your version of the file, but you are not obligated to do so.  If
+    you do not wish to do so, delete this exception statement from
+    your version.
+*/
+
+#ifndef __QGPGME_DECRYPTVERIFYJOB_P_H__
+#define __QGPGME_DECRYPTVERIFYJOB_P_H__
+
+#include "job_p.h"
+
+namespace QGpgME
+{
+
+struct DecryptVerifyJobPrivate : public JobPrivate
+{
+    QString m_inputFilePath;
+    QString m_outputFilePath;
+};
+
+}
+
+#endif // __QGPGME_DECRYPTVERIFYJOB_P_H__

lang/qt/src/job.cpp

@@ -44,7 +44,6 @@
 #include "keylistjob.h"
 #include "listallkeysjob.h"
 #include "decryptjob.h"
-#include "decryptverifyjob.h"
 #include "signkeyjob.h"
 #include "verifydetachedjob.h"
 #include "verifyopaquejob.h"
@@ -162,7 +161,6 @@ void QGpgME::Job::startNow()
 make_job_subclass(KeyListJob)
 make_job_subclass(ListAllKeysJob)
 make_job_subclass(DecryptJob)
-make_job_subclass(DecryptVerifyJob)
 make_job_subclass(SignKeyJob)
 make_job_subclass(VerifyDetachedJob)
 make_job_subclass(VerifyOpaqueJob)
@@ -197,7 +195,6 @@ make_job_subclass(SetPrimaryUserIDJob)
 #include "keylistjob.moc"
 #include "listallkeysjob.moc"
 #include "decryptjob.moc"
-#include "decryptverifyjob.moc"
 #include "signkeyjob.moc"
 #include "verifydetachedjob.moc"
 #include "verifyopaquejob.moc"

lang/qt/src/qgpgmedecryptverifyjob.cpp

@@ -39,25 +39,55 @@
 #include "qgpgmedecryptverifyjob.h"
 
 #include "dataprovider.h"
+#include "decryptverifyjob_p.h"
+#include "util.h"
 
-#include "context.h"
+#include <context.h>
-#include "decryptionresult.h"
+#include <decryptionresult.h>
-#include "verificationresult.h"
+#include <verificationresult.h>
-#include "data.h"
+#include <data.h>
 
 #include <QDebug>
 #include "qgpgme_debug.h"
 
 #include <QBuffer>
+#include <QFile>
 
 #include <cassert>
 
 using namespace QGpgME;
 using namespace GpgME;
 
+namespace
+{
+
+class QGpgMEDecryptVerifyJobPrivate : public DecryptVerifyJobPrivate
+{
+    QGpgMEDecryptVerifyJob *q = nullptr;
+
+public:
+    QGpgMEDecryptVerifyJobPrivate(QGpgMEDecryptVerifyJob *qq)
+        : q{qq}
+    {
+    }
+
+    ~QGpgMEDecryptVerifyJobPrivate() override = default;
+
+private:
+    GpgME::Error startIt() override;
+
+    void startNow() override
+    {
+        q->run();
+    }
+};
+
+}
+
 QGpgMEDecryptVerifyJob::QGpgMEDecryptVerifyJob(Context *context)
     : mixin_type(context)
 {
+    setJobPrivate(this, std::unique_ptr<QGpgMEDecryptVerifyJobPrivate>{new QGpgMEDecryptVerifyJobPrivate{this}});
     lateInitialization();
 }
 
@@ -112,6 +142,43 @@ static QGpgMEDecryptVerifyJob::result_type decrypt_verify_qba(Context *ctx, cons
     return decrypt_verify(ctx, nullptr, buffer, std::shared_ptr<QIODevice>());
 }
 
+static QGpgMEDecryptVerifyJob::result_type decrypt_verify_from_filename(Context *ctx,
+                                                                        const QString &inputFilePath,
+                                                                        const QString &outputFilePath)
+{
+    Data indata;
+#ifdef Q_OS_WIN
+    indata.setFileName(inputFilePath().toUtf8().constData());
+#else
+    indata.setFileName(QFile::encodeName(inputFilePath).constData());
+#endif
+
+    PartialFileGuard partFileGuard{outputFilePath};
+    if (partFileGuard.tempFileName().isEmpty()) {
+        return std::make_tuple(DecryptionResult{Error::fromCode(GPG_ERR_EEXIST)}, VerificationResult{Error::fromCode(GPG_ERR_EEXIST)}, QByteArray{}, QString{}, Error{});
+    }
+
+    Data outdata;
+#ifdef Q_OS_WIN
+    outdata.setFileName(partFileGuard.tempFileName().toUtf8().constData());
+#else
+    outdata.setFileName(QFile::encodeName(partFileGuard.tempFileName()).constData());
+#endif
+
+    const auto results = ctx->decryptAndVerify(indata, outdata);
+    const auto &decryptionResult = results.first;
+    const auto &verificationResult = results.second;
+
+    if (!decryptionResult.error().code() && !verificationResult.error().code()) {
+        // the operation succeeded -> save the result under the requested file name
+        partFileGuard.commit();
+    }
+
+    Error ae;
+    const QString log = _detail::audit_log_as_html(ctx, ae);
+    return std::make_tuple(decryptionResult, verificationResult, QByteArray{}, log, ae);
+}
+
 Error QGpgMEDecryptVerifyJob::start(const QByteArray &cipherText)
 {
     run(std::bind(&decrypt_verify_qba, std::placeholders::_1, cipherText));
@@ -132,10 +199,22 @@ QGpgME::QGpgMEDecryptVerifyJob::exec(const QByteArray &cipherText, QByteArray &p
     return mResult;
 }
 
-//PENDING(marc) implement showErrorDialog()
-
 void QGpgMEDecryptVerifyJob::resultHook(const result_type &tuple)
 {
     mResult = std::make_pair(std::get<0>(tuple), std::get<1>(tuple));
 }
+
+GpgME::Error QGpgMEDecryptVerifyJobPrivate::startIt()
+{
+    if (m_inputFilePath.isEmpty() || m_outputFilePath.isEmpty()) {
+        return Error::fromCode(GPG_ERR_INV_VALUE);
+    }
+
+    q->run([=](Context *ctx) {
+        return decrypt_verify_from_filename(ctx, m_inputFilePath, m_outputFilePath);
+    });
+
+    return {};
+}
+
 #include "qgpgmedecryptverifyjob.moc"

lang/qt/tests/Makefile.am

@@ -89,6 +89,7 @@ t_wkdlookup_SOURCES = t-wkdlookup.cpp $(support_src)
 t_import_SOURCES = t-import.cpp $(support_src)
 t_revokekey_SOURCES = t-revokekey.cpp $(support_src)
 t_setprimaryuserid_SOURCES = t-setprimaryuserid.cpp $(support_src)
+run_decryptverifyjob_SOURCES = run-decryptverifyjob.cpp
 run_decryptverifyarchivejob_SOURCES = run-decryptverifyarchivejob.cpp
 run_encryptarchivejob_SOURCES = run-encryptarchivejob.cpp
 run_encryptjob_SOURCES = run-encryptjob.cpp
@@ -113,6 +114,7 @@ noinst_PROGRAMS = \
 	t-trustsignatures t-changeexpiryjob t-wkdlookup t-import t-revokekey \
 	t-setprimaryuserid \
 	run-decryptverifyarchivejob \
+	run-decryptverifyjob \
 	run-encryptarchivejob \
 	run-encryptjob \
 	run-importjob run-exportjob run-receivekeysjob run-refreshkeysjob \

lang/qt/tests/run-decryptverifyjob.cpp

@@ -0,0 +1,163 @@
+/*
+    run-decryptverifyjob.cpp
+
+    This file is part of QGpgME's test suite.
+    Copyright (c) 2023 by g10 Code GmbH
+    Software engineering by Ingo Klöcker <dev@ingo-kloecker.de>
+
+    QGpgME is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License,
+    version 2, as published by the Free Software Foundation.
+
+    QGpgME is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+    In addition, as a special exception, the copyright holders give
+    permission to link the code of this program with any edition of
+    the Qt library by Trolltech AS, Norway (or with modified versions
+    of Qt that use the same license as Qt), and distribute linked
+    combinations including the two.  You must obey the GNU General
+    Public License in all respects for all of the code used other than
+    Qt.  If you modify this file, you may extend this exception to
+    your version of the file, but you are not obligated to do so.  If
+    you do not wish to do so, delete this exception statement from
+    your version.
+*/
+
+#ifdef HAVE_CONFIG_H
+ #include "config.h"
+#endif
+
+#include <protocol.h>
+#include <decryptverifyjob.h>
+
+#include <QCommandLineParser>
+#include <QCoreApplication>
+#include <QDebug>
+#include <QFile>
+#include <QTimer>
+
+#include <context.h>
+#include <decryptionresult.h>
+#include <verificationresult.h>
+
+#include <iostream>
+
+using namespace GpgME;
+
+std::ostream &operator<<(std::ostream &os, const QString &s)
+{
+    return os << s.toLocal8Bit().constData();
+}
+
+struct CommandLineOptions {
+    QString inputFile;
+    QString outputFile;
+    std::chrono::seconds cancelTimeout{0};
+};
+
+CommandLineOptions parseCommandLine(const QStringList &arguments)
+{
+    CommandLineOptions options;
+
+    QCommandLineParser parser;
+    parser.setApplicationDescription("Test program for DecryptVerifyJob");
+    parser.addHelpOption();
+    parser.addOptions({
+        {{"o", "output"}, "Write output to FILE.", "FILE"},
+        {"cancel-after", "Cancel the running job after SECONDS seconds.", "SECONDS"},
+    });
+    parser.addPositionalArgument("file", "File to decrypt", "FILE");
+
+    parser.process(arguments);
+
+    const auto args = parser.positionalArguments();
+    if (args.size() != 1) {
+        parser.showHelp(1);
+    }
+
+    options.inputFile = args.front();
+    options.outputFile = parser.value("output");
+    if (parser.isSet("cancel-after")) {
+        bool ok;
+        options.cancelTimeout = std::chrono::seconds{parser.value("cancel-after").toInt(&ok)};
+        if (!ok) {
+            options.cancelTimeout = std::chrono::seconds{-1};
+        }
+    }
+
+    return options;
+}
+
+int main(int argc, char **argv)
+{
+    GpgME::initializeLibrary();
+
+    QCoreApplication app{argc, argv};
+    app.setApplicationName("run-decryptverifyjob");
+
+    const auto options = parseCommandLine(app.arguments());
+    if (options.cancelTimeout.count() < 0) {
+        std::cerr << "Ignoring invalid timeout for cancel." << std::endl;
+    }
+
+    std::shared_ptr<QFile> output;
+    if (options.outputFile.isEmpty() || options.outputFile == QLatin1String{"-"}) {
+        output.reset(new QFile);
+        output->open(stdout, QIODevice::WriteOnly);
+    } else {
+        if (QFile::exists(options.outputFile)) {
+            qCritical() << "File" << options.outputFile << "exists. Bailing out.";
+            return 1;
+        }
+    }
+
+    auto job = QGpgME::openpgp()->decryptVerifyJob();
+    if (!job) {
+        std::cerr << "Error: Could not create job" << std::endl;
+        return 1;
+    }
+    QObject::connect(job,
+                     &QGpgME::DecryptVerifyJob::result,
+                     &app,
+                     [](const GpgME::DecryptionResult &decryptionResult,
+                        const GpgME::VerificationResult &verificationResult,
+                        const QByteArray &,
+                        const QString &auditLog,
+                        const GpgME::Error &) {
+        std::cerr << "Diagnostics: " << auditLog << std::endl;
+        std::cerr << "Decryption Result: " << decryptionResult << std::endl;
+        std::cerr << "Verification Result: " << verificationResult << std::endl;
+        qApp->quit();
+    });
+    if (options.cancelTimeout.count() > 0) {
+        QTimer::singleShot(options.cancelTimeout, job, [job]() {
+            std::cerr << "Canceling job" << std::endl;
+            job->slotCancel();
+        });
+    }
+
+    std::shared_ptr<QFile> input;
+    GpgME::Error err;
+    if (output) {
+        input.reset(new QFile{options.inputFile});
+        input->open(QIODevice::ReadOnly);
+        job->start(input, output);
+    } else {
+        job->setInputFile(options.inputFile);
+        job->setOutputFile(options.outputFile);
+        err = job->startIt();
+    }
+    if (err) {
+        std::cerr << "Error: Starting the job failed: " << err.asString() << std::endl;
+        return 1;
+    }
+
+    return app.exec();
+}