Refactoring, code-cleaning, etc.

Signed-off-by: alex-z <[email protected]>

src/libsync/encryptedfoldermetadatahandler.h

@@ -25,6 +25,7 @@
 namespace OCC {
 class FolderMetadata;
 class SyncJournalDb;
+// all metadata operations with server must be performed via this class
 class OWNCLOUDSYNC_EXPORT EncryptedFolderMetadataHandler : public QObject
 {
     Q_OBJECT

src/libsync/foldermetadata.cpp

@@ -535,19 +535,18 @@ const QSet<QByteArray>& FolderMetadata::keyChecksums() const
     return _keyChecksums;
 }
 
-const QSet<QByteArray>& FolderMetadata::keyChecksumsRemoved() const
-{
-    return _keyChecksumsRemoved;
-}
-
 void FolderMetadata::initEmptyMetadata()
 {
     if (_account->capabilities().clientSideEncryptionVersion() < 2.0) {
         return initEmptyMetadataLegacy();
     }
     qCDebug(lcCseMetadata()) << "Setting up empty metadata v2";
     if (_isRootEncryptedFolder) {
-        addUser(_account->davUser(), _account->e2e()->_certificate);
+        if (!addUser(_account->davUser(), _account->e2e()->_certificate)) {
+            qCDebug(lcCseMetadata) << "Empty metadata setup failed. Could not add first user.";
+            _account->reportClientStatus(OCC::ClientStatusReportingStatus::E2EeError_GeneralError);
+            return;
+        }
         _metadataKeyForDecryption = _metadataKeyForEncryption;
     }
     _isMetadataValid = true;
@@ -1109,12 +1108,6 @@ void FolderMetadata::createNewMetadataKeyForEncryption()
     if (!_isRootEncryptedFolder) {
         return;
     }
-    if (!metadataKeyForEncryption().isEmpty()) {
-        const auto checksumToRemove = calcSha256(metadataKeyForEncryption());
-        // TODO: since we are not supposed to remove checksums, we might as well get rid of _keyChecksumsRemoved
-        _keyChecksumsRemoved.insert(checksumToRemove);
-        //_keyChecksums.remove(checksumToRemove);
-    }
     _metadataKeyForEncryption = EncryptionHelper::generateRandom(metadataKeySize);
     if (!metadataKeyForEncryption().isEmpty()) {
         _keyChecksums.insert(calcSha256(metadataKeyForEncryption()));

src/libsync/foldermetadata.h

@@ -1,6 +1,6 @@
 #pragma once
 /*
- * Copyright (C) 2023 by Oleksandr Zolotov <[email protected]>
+ * Copyright (C) 2024 by Oleksandr Zolotov <[email protected]>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -32,11 +32,13 @@ class TestClientSideEncryptionV2;
 class TestSecureFileDrop;
 namespace OCC
 {
+ // Handles parsing and altering the metadata, encryption and decryption. Setup of the instance is always asynchronouse and emits void setupComplete()
 class OWNCLOUDSYNC_EXPORT FolderMetadata : public QObject
 {
     friend class TestClientSideEncryptionV2;
     friend class TestSecureFileDrop;
     Q_OBJECT
+
     // represents a user that has access to a folder for which metadata instance is created
     struct FolderUser {
         QString userId;
@@ -52,7 +54,7 @@ class OWNCLOUDSYNC_EXPORT FolderMetadata : public QObject
         Version2_0,
     };
 
-    // represents a user that has access to a specific filedrop entry
+    // represents a user that has access to a specific filedrop entry of the current folder
     struct FileDropEntryUser {
         QString userId;
         QByteArray decryptedFiledropKey;
@@ -113,15 +115,16 @@ class OWNCLOUDSYNC_EXPORT FolderMetadata : public QObject
 
     [[nodiscard]] bool moveFromFileDropToFiles();
 
-    bool addUser(const QString &userId, const QSslCertificate &certificate); //adds a user to have access to this folder (always generates new metadata key)
-    bool removeUser(const QString &userId); // removes a user from this folder and removes and generates a new metadata key
+    // adds a user to have access to this folder (always generates new metadata key)
+    [[nodiscard]] bool addUser(const QString &userId, const QSslCertificate &certificate);
+    // removes a user from this folder and removes and generates a new metadata key
+    [[nodiscard]] bool removeUser(const QString &userId);
 
     [[nodiscard]] const QByteArray metadataKeyForEncryption() const;
     [[nodiscard]] const QByteArray metadataKeyForDecryption() const;
     [[nodiscard]] const QSet<QByteArray> &keyChecksums() const;
-    [[nodiscard]] const QSet<QByteArray> &keyChecksumsRemoved() const;
 
-    QByteArray encryptedMetadata();
+    [[nodiscard]] QByteArray encryptedMetadata();
 
     [[nodiscard]] EncryptionStatusEnums::ItemEncryptionStatus existingMetadataEncryptionStatus() const;
     [[nodiscard]] EncryptionStatusEnums::ItemEncryptionStatus encryptedMetadataEncryptionStatus() const;
@@ -135,8 +138,13 @@ class OWNCLOUDSYNC_EXPORT FolderMetadata : public QObject
 
     [[nodiscard]] QByteArray initialMetadata() const;
 
+public slots:
+    void addEncryptedFile(const EncryptedFile &f);
+    void removeEncryptedFile(const EncryptedFile &f);
+    void removeAllEncryptedFiles();
+
 private:
-    QByteArray encryptedMetadataLegacy();
+    [[nodiscard]] QByteArray encryptedMetadataLegacy();
 
     [[nodiscard]] bool verifyMetadataKey(const QByteArray &metadataKey) const;
 
@@ -165,11 +173,6 @@ class OWNCLOUDSYNC_EXPORT FolderMetadata : public QObject
 
     static QByteArray prepareMetadataForSignature(const QJsonDocument &fullMetadata);
 
-public slots:
-    void addEncryptedFile(const EncryptedFile &f);
-    void removeEncryptedFile(const EncryptedFile &f);
-    void removeAllEncryptedFiles();
-
 private slots:
     void initMetadata();
     void initEmptyMetadata();
@@ -196,34 +199,43 @@ private slots:
     QByteArray _initialMetadata;
 
     bool _isRootEncryptedFolder = false;
+    // always contains the last generated metadata key (non-encrypted and non-base64)
     QByteArray _metadataKeyForEncryption;
-    QByteArray _metadataKeyForDecryption; // used for storing initial metadataKey to use for decryption, especially in nested folders when changing the metadataKey and re-encrypting nested dirs
-    QSet<QByteArray> _keyChecksums;
-    QSet<QByteArray> _keyChecksumsRemoved;
+    // used for storing initial metadataKey to use for decryption, especially in nested folders when changing the metadataKey and re-encrypting nested dirs
+    QByteArray _metadataKeyForDecryption;
     QByteArray _metadataNonce;
+    // metadatakey checksums for validation during setting up from existing metadata
+    QSet<QByteArray> _keyChecksums;
 
+    // filedrop part non-parsed, for upload in case parsing can not be done (due to not having access for the current user, etc.)
     QJsonObject _fileDrop;
     // used by unit tests, must get assigned simultaneously with _fileDrop and never erased
     QJsonObject _fileDropFromServer;
 
-    QMap<int, QByteArray> _metadataKeys; //legacy, remove after migration is done
+    // legacy, remove after migration is done
+    QMap<int, QByteArray> _metadataKeys;
 
+    // users that have access to current folder's "ciphertext", except "filedrop" part
     QHash<QString, FolderUser> _folderUsers;
 
+    // must increment on each metadata upload
     quint64 _counter = 0;
 
     MetadataVersion _existingMetadataVersion = MetadataVersion::VersionUndefined;
     MetadataVersion _encryptedMetadataVersion = MetadataVersion::VersionUndefined;
 
+    // generated each time QByteArray encryptedMetadata() is called, and will later be used for validation if uploaded
     QByteArray _metadataSignature;
-
+    // signature from server-side metadata
     QByteArray _initialSignature;
 
+    // both files and folders info
     QVector<EncryptedFile> _files;
 
-    // for parsed filedrop entries
+    // parsed filedrop entries ready for move
     QVector<FileDropEntry> _fileDropEntries;
 
+    // sets to "true" on successful parse
     bool _isMetadataValid = false;
 
     QScopedPointer<EncryptedFolderMetadataHandler> _encryptedFolderMetadataHandler;

src/libsync/updatee2eefolderusersmetadatajob.cpp

@@ -201,7 +201,7 @@ void UpdateE2eeFolderUsersMetadataJob::scheduleSubJobs()
             const auto subJob = new UpdateE2eeFolderUsersMetadataJob(_account, _journalDb, _syncFolderRemotePath, UpdateE2eeFolderUsersMetadataJob::ReEncrypt, QString::fromUtf8(record._e2eMangledName));
             subJob->setMetadataKeyForEncryption(folderMetadata->metadataKeyForEncryption());
             subJob->setMetadataKeyForDecryption(folderMetadata->metadataKeyForDecryption());
-            subJob->setKeyChecksums(folderMetadata->keyChecksums() + folderMetadata->keyChecksumsRemoved());
+            subJob->setKeyChecksums(folderMetadata->keyChecksums());
             subJob->setParent(this);
             subJob->setFolderToken(_encryptedFolderMetadataHandler->folderToken());
             _subJobs.insert(subJob);

test/testclientsideencryptionv2.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) by Oleksandr Zolotov <[email protected]>
+ * Copyright (C) 2024 by Oleksandr Zolotov <[email protected]>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -214,6 +214,10 @@ private slots:
 
         QVERIFY(metadata->addUser(_secondAccount->davUser(), _secondAccount->e2e()->_certificate));
 
+        QVERIFY(metadata->removeUser(_secondAccount->davUser()));
+
+        QVERIFY(metadata->addUser(_secondAccount->davUser(), _secondAccount->e2e()->_certificate));
+
         const auto encryptedMetadata = metadata->encryptedMetadata();
         QVERIFY(!encryptedMetadata.isEmpty());
 

test/testsecurefiledrop.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) by Oleksandr Zolotov <[email protected]>
+ * Copyright (C) 2024 by Oleksandr Zolotov <[email protected]>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by