[Sync] Initial support for encrypting any datatype (no UI hookup yet).

chrome/browser/sync/syncable/nigori_util.cc

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sync/syncable/nigori_util.h"
+
+#include <queue>
+#include <string>
+#include <vector>
+
+#include "chrome/browser/sync/engine/syncer_util.h"
+#include "chrome/browser/sync/syncable/syncable.h"
+#include "chrome/browser/sync/util/cryptographer.h"
+
+namespace syncable {
+
+ModelTypeSet GetEncryptedDataTypes(BaseTransaction* const trans) {
+  std::string nigori_tag = ModelTypeToRootTag(syncable::NIGORI);
+  Entry entry(trans, GET_BY_SERVER_TAG, nigori_tag);
+  if (!entry.good()) {
+    VLOG(1) << "Nigori node not found, assuming no encrypted datatypes.";
+    return ModelTypeSet();
+  }
+  if (NIGORI != entry.GetModelType()) {
+    // Can happen if we fail to apply the nigori node due to a conflict.
+    VLOG(1) << "Nigori node does not have nigori extension. Assuming no"
+            << " encrypted datatypes.";
+    return ModelTypeSet();
+  }
+  const sync_pb::EntitySpecifics& specifics = entry.Get(SPECIFICS);
+  return GetEncryptedDataTypesFromNigori(
+      specifics.GetExtension(sync_pb::nigori));
+}
+
+ModelTypeSet GetEncryptedDataTypesFromNigori(
+    const sync_pb::NigoriSpecifics& nigori) {
+  // We don't check NIGORI datatype, it uses its own encryption scheme.
+  ModelTypeSet encrypted_types;
+  if (nigori.encrypt_bookmarks())
+    encrypted_types.insert(BOOKMARKS);
+  if (nigori.encrypt_preferences())
+    encrypted_types.insert(PREFERENCES);
+  if (nigori.encrypt_passwords())
+    encrypted_types.insert(PASSWORDS);
+  if (nigori.encrypt_autofill_profile())
+    encrypted_types.insert(AUTOFILL_PROFILE);
+  if (nigori.encrypt_autofill())
+    encrypted_types.insert(AUTOFILL);
+  if (nigori.encrypt_themes())
+    encrypted_types.insert(THEMES);
+  if (nigori.encrypt_typed_urls())
+    encrypted_types.insert(TYPED_URLS);
+  if (nigori.encrypt_extensions())
+    encrypted_types.insert(EXTENSIONS);
+  if (nigori.encrypt_sessions())
+    encrypted_types.insert(SESSIONS);
+  if (nigori.encrypt_apps())
+    encrypted_types.insert(APPS);
+  return encrypted_types;
+}
+
+void FillNigoriEncryptedTypes(const ModelTypeSet& types,
+    sync_pb::NigoriSpecifics* nigori) {
+  DCHECK(nigori);
+  nigori->set_encrypt_bookmarks(types.count(BOOKMARKS) > 0);
+  nigori->set_encrypt_preferences(types.count(PREFERENCES) > 0);
+  nigori->set_encrypt_passwords(types.count(PASSWORDS) > 0);
+  nigori->set_encrypt_autofill_profile(types.count(AUTOFILL_PROFILE) > 0);
+  nigori->set_encrypt_autofill(types.count(AUTOFILL) > 0);
+  nigori->set_encrypt_themes(types.count(THEMES) > 0);
+  nigori->set_encrypt_typed_urls(types.count(TYPED_URLS) > 0);
+  nigori->set_encrypt_extensions(types.count(EXTENSIONS) > 0);
+  nigori->set_encrypt_sessions(types.count(SESSIONS) > 0);
+  nigori->set_encrypt_apps(types.count(APPS) > 0);
+}
+
+bool ProcessUnsyncedChangesForEncryption(
+    WriteTransaction* const trans,
+    const ModelTypeSet& encrypted_types,
+    browser_sync::Cryptographer* cryptographer) {
+  // Get list of all datatypes with unsynced changes. It's possible that our
+  // local changes need to be encrypted if encryption for that datatype was
+  // just turned on (and vice versa). This should never affect passwords.
+  std::vector<int64> handles;
+  browser_sync::SyncerUtil::GetUnsyncedEntries(trans, &handles);
+  for (size_t i = 0; i < handles.size(); ++i) {
+    MutableEntry entry(trans, GET_BY_HANDLE, handles[i]);
+    sync_pb::EntitySpecifics new_specifics;
+    const sync_pb::EntitySpecifics& entry_specifics = entry.Get(SPECIFICS);
+    ModelType type = entry.GetModelType();
+    if (type == PASSWORDS)
+      continue;
+    if (encrypted_types.count(type) > 0 &&
+        !entry_specifics.has_encrypted()) {
+      // This entry now requires encryption.
+      AddDefaultExtensionValue(type, &new_specifics);
+      if (!cryptographer->Encrypt(
+          entry_specifics,
+          new_specifics.mutable_encrypted())) {
+        LOG(ERROR) << "Could not encrypt data for newly encrypted type " <<
+            ModelTypeToString(type);
+        NOTREACHED();
+        return false;
+      } else {
+        VLOG(1) << "Encrypted change for newly encrypted type " <<
+            ModelTypeToString(type);
+        entry.Put(SPECIFICS, new_specifics);
+      }
+    } else if (encrypted_types.count(type) == 0 &&
+               entry_specifics.has_encrypted()) {
+      // This entry no longer requires encryption.
+      if (!cryptographer->Decrypt(entry_specifics.encrypted(),
+                                  &new_specifics)) {
+        LOG(ERROR) << "Could not decrypt data for newly unencrypted type " <<
+            ModelTypeToString(type);
+        NOTREACHED();
+        return false;
+      } else {
+        VLOG(1) << "Decrypted change for newly unencrypted type " <<
+            ModelTypeToString(type);
+        entry.Put(SPECIFICS, new_specifics);
+      }
+    }
+  }
+  return true;
+}
+
+bool VerifyUnsyncedChangesAreEncrypted(
+    BaseTransaction* const trans,
+    const ModelTypeSet& encrypted_types) {
+  std::vector<int64> handles;
+  browser_sync::SyncerUtil::GetUnsyncedEntries(trans, &handles);
+  for (size_t i = 0; i < handles.size(); ++i) {
+    Entry entry(trans, GET_BY_HANDLE, handles[i]);
+    if (!entry.good()) {
+      NOTREACHED();
+      return false;
+    }
+    const sync_pb::EntitySpecifics& entry_specifics = entry.Get(SPECIFICS);
+    ModelType type = entry.GetModelType();
+    if (type == PASSWORDS)
+      continue;
+    if (encrypted_types.count(type) > 0 &&
+        !entry_specifics.has_encrypted()) {
+      // This datatype requires encryption but this data is not encrypted.
+      return false;
+    }
+  }
+  return true;
+}
+
+// Mainly for testing.
+bool VerifyDataTypeEncryption(BaseTransaction* const trans,
+                              ModelType type,
+                              bool is_encrypted) {
+  if (type == PASSWORDS || type == NIGORI) {
+    NOTREACHED();
+    return true;
+  }
+  std::string type_tag = ModelTypeToRootTag(type);
+  Entry type_root(trans, GET_BY_SERVER_TAG, type_tag);
+  if (!type_root.good()) {
+    NOTREACHED();
+    return false;
+  }
+
+  std::queue<Id> to_visit;
+  Id id_string =
+      trans->directory()->GetFirstChildId(trans, type_root.Get(ID));
+  to_visit.push(id_string);
+  while (!to_visit.empty()) {
+    id_string = to_visit.front();
+    to_visit.pop();
+    if (id_string.IsRoot())
+      continue;
+
+    Entry child(trans, GET_BY_ID, id_string);
+    if (!child.good()) {
+      NOTREACHED();
+      return false;
+    }
+    if (child.Get(IS_DIR)) {
+      // Traverse the children.
+      to_visit.push(
+          trans->directory()->GetFirstChildId(trans, child.Get(ID)));
+    } else {
+      const sync_pb::EntitySpecifics& specifics = child.Get(SPECIFICS);
+      DCHECK_EQ(type, child.GetModelType());
+      DCHECK_EQ(type, GetModelTypeFromSpecifics(specifics));
+      if (specifics.has_encrypted() != is_encrypted)
+        return false;
+    }
+    // Push the successor.
+    to_visit.push(child.Get(NEXT_ID));
+  }
+  return true;
+}
+
+}  // namespace syncable