1 files changed, 114 insertions, 0 deletions
diff --git a/src/client/QXmppEncryptedFileSharingProvider.cpp b/src/client/QXmppEncryptedFileSharingProvider.cpp
new file mode 100644
index 00000000..b2638d05
--- /dev/null
+++ b/src/client/QXmppEncryptedFileSharingProvider.cpp
@@ -0,0 +1,114 @@
+// SPDX-FileCopyrightText: 2022 Jonah Brüchert <jbb@kaidan.im>
+// SPDX-FileCopyrightText: 2022 Linus Jahn <lnj@kaidan.im>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+#include "QXmppEncryptedFileSharingProvider.h"
+
+#include "QXmppFileEncryption.h"
+#include "QXmppFileMetadata.h"
+#include "QXmppFileSharingManager.h"
+#include "QXmppFutureUtils_p.h"
+#include "QXmppUtils.h"
+
+#include "QcaInitializer_p.h"
+#include <QMimeDatabase>
+
+using namespace QXmpp;
+using namespace QXmpp::Private;
+
+///
+/// \class QXmppEncryptedFileSharingProvider
+///
+/// Encrypts or decrypts files on the fly when uploading or downloading.
+///
+/// \since QXmpp 1.5
+///
+
+class QXmppEncryptedFileSharingProviderPrivate
+{
+public:
+    QcaInitializer init;
+    QXmppFileSharingManager *manager;
+    std::shared_ptr<QXmppFileSharingProvider> uploadBaseProvider;
+};
+
+///
+/// \brief Create a new QXmppEncryptedFileSharingProvider
+///
+/// \param manager QXmppFileSharingManager to be used to find other providers for downloading
+/// encrypted files.
+/// \param uploadBaseProvider Provider to be used for uploading the encrypted files.
+///
+QXmppEncryptedFileSharingProvider::QXmppEncryptedFileSharingProvider(
+    QXmppFileSharingManager *manager,
+    std::shared_ptr<QXmppFileSharingProvider> uploadBaseProvider)
+    : d(std::make_unique<QXmppEncryptedFileSharingProviderPrivate>())
+{
+    d->manager = manager;
+    d->uploadBaseProvider = std::move(uploadBaseProvider);
+}
+
+QXmppEncryptedFileSharingProvider::~QXmppEncryptedFileSharingProvider() = default;
+
+auto QXmppEncryptedFileSharingProvider::downloadFile(const std::any &source,
+                                                     std::unique_ptr<QIODevice> target,
+                                                     std::function<void(quint64, quint64)> reportProgress,
+                                                     std::function<void(DownloadResult)> reportFinished)
+    -> std::shared_ptr<Download>
+{
+    QXmppEncryptedFileSource encryptedSource;
+    try {
+        encryptedSource = std::any_cast<QXmppEncryptedFileSource>(source);
+    } catch (const std::bad_any_cast &) {
+        qFatal("QXmppEncryptedFileSharingProvider::downloadFile can only handle QXmppEncryptedFileSource sources");
+    }
+
+    auto output = std::make_unique<Encryption::DecryptionDevice>(std::move(target), encryptedSource.cipher(), encryptedSource.iv(), encryptedSource.key());
+
+    // find provider for source of encrypted file
+    std::any httpSource = encryptedSource.httpSources().front();
+    if (auto provider = d->manager->providerForSource(httpSource)) {
+        return provider->downloadFile(httpSource, std::move(output), std::move(reportProgress), std::move(reportFinished));
+    }
+
+    reportFinished(QXmppError { QStringLiteral("No basic file sharing provider available for encrypted file."), {} });
+    return {};
+}
+
+auto QXmppEncryptedFileSharingProvider::uploadFile(std::unique_ptr<QIODevice> data,
+                                                   const QXmppFileMetadata &,
+                                                   std::function<void(quint64, quint64)> reportProgress,
+                                                   std::function<void(UploadResult)> reportFinished)
+    -> std::shared_ptr<Upload>
+{
+    auto cipher = Aes256CbcPkcs7;
+    auto key = Encryption::generateKey(cipher);
+    auto iv = Encryption::generateInitializationVector(cipher);
+
+    auto encDevice = std::make_unique<Encryption::EncryptionDevice>(std::move(data), cipher, key, iv);
+    auto encryptedSize = encDevice->size();
+
+    QXmppFileMetadata metadata;
+    metadata.setFilename(QXmppUtils::generateStanzaHash(10));
+    metadata.setMediaType(QMimeDatabase().mimeTypeForName("application/octet-stream"));
+    metadata.setSize(encryptedSize);
+
+    // find provider for source of encrypted file
+    Q_ASSERT(d->uploadBaseProvider);
+    return d->uploadBaseProvider->uploadFile(
+        std::move(encDevice),
+        metadata,
+        std::move(reportProgress),
+        [=, reportFinished = std::move(reportFinished)](UploadResult result) {
+            auto encryptedResult = visitForward<UploadResult>(std::move(result), [&](std::any httpSourceAny) {
+                QXmppEncryptedFileSource encryptedSource;
+                encryptedSource.setKey(key);
+                encryptedSource.setIv(iv);
+                encryptedSource.setHttpSources({ std::any_cast<QXmppHttpFileSource>(std::move(httpSourceAny)) });
+
+                return encryptedSource;
+            });
+            reportFinished(std::move(encryptedResult));
+        });
+}