qt: Support WKD lookup without implicit import

* lang/qt/src/Makefile.am (qgpgme_sources): Add qgpgmewkdlookupjob.cpp,
wkdlookupresult.cpp.
(qgpgme_headers): Add wkdlookupjob.h, wkdlookupresult.h.
(camelcase_headers): Add WKDLookupJob, WKDLookupResult.
(private_qgpgme_headers): Add qgpgmewkdlookupjob.h.
(qgpgme_moc_sources): Add qgpgmewkdlookupjob.moc, wkdlookupjob.moc.
* lang/qt/src/job.cpp: Define c'tor and d'tor of WKDLookupJob.
* lang/qt/src/protocol.h (Protocol::wkdLookupJob): New.
* lang/qt/src/protocol_p.h (Protocol::wkdLookupJob): New.
* lang/qt/src/qgpgmewkdlookupjob.cpp, lang/qt/src/qgpgmewkdlookupjob.h,
lang/qt/src/wkdlookupjob.h, lang/qt/src/wkdlookupresult.cpp,
lang/qt/src/wkdlookupresult.h: New.

* lang/qt/tests/Makefile.am (EXTRA_DIST): Add final.test.
(the_tests): New.
(TESTS): Remove all t-*. Add $(the_tests) and final.test.
(moc_files): Add t-wkdlookup.moc.
(t_wkdlookup_SOURCES): New.
(noinst_PROGRAMS): Add t-wkdlookup.
* lang/qt/tests/final.test: New.
* lang/qt/tests/t-support.h (QTest::toString): New template
specialization for std::string.
* lang/qt/tests/t-wkdlookup.cpp: New.
--

The new WKDLookupJob allows running a WKD lookup without implicit
import of the retrieved key. This makes it possible to do WKD lookups
similar to keyserver lookups (aka external keylistings).

The new final.test pseudo test stops a dirmngr that may have been
started by the tests. The toString() template specialization enables
printing of the actual and expected values in case of failed QCOMPARE.

GnuPG-bug-id: 5728

1 files changed, 182 insertions, 0 deletions

diff --git a/lang/qt/src/qgpgmewkdlookupjob.cpp b/lang/qt/src/qgpgmewkdlookupjob.cpp
new file mode 100644
index 00000000..fcb757e1
--- /dev/null
+++ b/lang/qt/src/qgpgmewkdlookupjob.cpp
@@ -0,0 +1,182 @@
+/*
+    qgpgmewkdlookupjob.cpp
+
+    This file is part of qgpgme, the Qt API binding for gpgme
+    Copyright (c) 2021 g10 Code GmbH
+    Software engineering by Ingo Klöcker <[email protected]>
+
+    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 "qgpgmewkdlookupjob.h"
+
+#include "qgpgme_debug.h"
+
+#include <gpgme++/context.h>
+#include <gpgme++/data.h>
+#include <gpgme++/defaultassuantransaction.h>
+
+#include <gpg-error.h>
+
+using namespace QGpgME;
+using namespace GpgME;
+
+QGpgMEWKDLookupJob::QGpgMEWKDLookupJob(Context *context)
+    : mixin_type{context}
+{
+    lateInitialization();
+}
+
+QGpgMEWKDLookupJob::~QGpgMEWKDLookupJob() = default;
+
+static GpgME::Error startDirmngr(Context *assuanCtx)
+{
+    Error err;
+
+    auto spawnCtx = std::unique_ptr<Context>{Context::createForEngine(SpawnEngine, &err)};
+    if (err) {
+        qCDebug(QGPGME_LOG) << "Error: Failed to get context for spawn engine (" << err.asString() << ")";
+    }
+
+    const auto dirmngrProgram = GpgME::dirInfo("dirmngr-name");
+    const auto homedir = GpgME::dirInfo("homedir");
+    const char *argv[] = {
+        dirmngrProgram,
+        "--homedir",
+        homedir,
+        "--daemon",
+        NULL
+    };
+    auto ignoreIO = Data{Data::null};
+    if (!err) {
+        qCDebug(QGPGME_LOG) << "Starting dirmngr ...";
+        err = spawnCtx->spawnAsync(dirmngrProgram, argv,
+                                   ignoreIO, ignoreIO, ignoreIO,
+                                   Context::SpawnDetached);
+    }
+
+    if (!err) {
+        // wait for socket to become available
+        int cnt = 0;
+        do {
+            ++cnt;
+            qCDebug(QGPGME_LOG) << "Waiting for dirmngr to start ...";
+            QThread::msleep(250 * cnt);
+            err = assuanCtx->assuanTransact("GETINFO version");
+        } while (err.code() == GPG_ERR_ASS_CONNECT_FAILED && cnt < 5);
+    }
+
+    return err;
+}
+
+static GpgME::Error setUpDirmngrAssuanConnection(Context *ctx)
+{
+    Error err;
+
+    const std::string dirmngrSocket = GpgME::dirInfo("dirmngr-socket");
+    err = ctx->setEngineFileName(dirmngrSocket.c_str());
+
+    if (!err) {
+        err = ctx->setEngineHomeDirectory("");
+    }
+
+    if (!err) {
+        // try do connect to dirmngr
+        err = ctx->assuanTransact("GETINFO version");
+        if (err.code() == GPG_ERR_ASS_CONNECT_FAILED) {
+            err = startDirmngr(ctx);
+        }
+    }
+
+    return err;
+}
+
+static GpgME::Error run_wkd_get(Context *ctx, const QString &email)
+{
+    Error err;
+
+    const auto cmd = std::string{"WKD_GET "} + email.toUtf8().toStdString();
+    err = ctx->assuanTransact(cmd.c_str());
+    if (err.code() == GPG_ERR_NO_NAME || err.code() == GPG_ERR_NO_DATA) {
+        // ignore those benign errors; GPG_ERR_NO_NAME indicates that the domain
+        // doesn't exist (on first request); GPG_ERR_NO_DATA indicates that
+        // no key for email is available via WKD or that the domain doesn't
+        // support WKD or that the domain doesn't exist (on subsequent requests
+        // using dirmngr's internal cache)
+        qCDebug(QGPGME_LOG) << "WKD_GET returned" << err.asString() << "; ignoring...";
+        err = {};
+    }
+    if (err) {
+        qCDebug(QGPGME_LOG) << "WKD_GET failed with" << err.asString();
+    }
+
+    return err;
+}
+
+static QGpgMEWKDLookupJob::result_type lookup_keys(Context *ctx, const QString &email)
+{
+    WKDLookupResult result;
+
+    Error err = setUpDirmngrAssuanConnection(ctx);
+
+    if (!err) {
+        err = run_wkd_get(ctx, email);
+    }
+
+    if (!err) {
+        const auto transaction = std::unique_ptr<DefaultAssuanTransaction>(dynamic_cast<DefaultAssuanTransaction*>(ctx->takeLastAssuanTransaction().release()));
+        const auto source = transaction->firstStatusLine("SOURCE");
+        const auto rawData = transaction->data();
+        if (rawData.size() == 0) {
+            qCDebug(QGPGME_LOG) << "No key found for" << email;
+            result = WKDLookupResult{GpgME::Data::null, {}, {}};
+        } else {
+            qCDebug(QGPGME_LOG) << "Found key for" << email << "at" << source.c_str();
+            result = WKDLookupResult{GpgME::Data{rawData.c_str(), rawData.size()}, source, {}};
+        }
+    }
+
+    return std::make_tuple(err ? WKDLookupResult{err} : result, QString{}, Error{});
+}
+
+Error QGpgMEWKDLookupJob::start(const QString &email)
+{
+    run(std::bind(&lookup_keys, std::placeholders::_1, email));
+    return Error();
+}
+
+WKDLookupResult QGpgMEWKDLookupJob::exec(const QString &email)
+{
+    const result_type r = lookup_keys(context(), email);
+    resultHook(r);
+    return std::get<0>(r);
+}
+
+#include "qgpgmewkdlookupjob.moc"