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//* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "Classifier.h"
#include "LookupCacheV4.h"
#include "nsIFile.h"
#include "nsNetCID.h"
#include "nsPrintfCString.h"
#include "nsThreadUtils.h"
#include "mozilla/Components.h"
#include "mozilla/EndianUtils.h"
#include "mozilla/Telemetry.h"
#include "mozilla/IntegerPrintfMacros.h"
#include "mozilla/LazyIdleThread.h"
#include "mozilla/Logging.h"
#include "mozilla/SyncRunnable.h"
#include "mozilla/Base64.h"
#include "mozilla/Unused.h"
#include "mozilla/UniquePtr.h"
#include "nsUrlClassifierDBService.h"
#include "nsUrlClassifierUtils.h"
// MOZ_LOG=UrlClassifierDbService:5
extern mozilla::LazyLogModule gUrlClassifierDbServiceLog;
#define LOG(args) \
MOZ_LOG(gUrlClassifierDbServiceLog, mozilla::LogLevel::Debug, args)
#define LOG_ENABLED() \
MOZ_LOG_TEST(gUrlClassifierDbServiceLog, mozilla::LogLevel::Debug)
#define STORE_DIRECTORY "safebrowsing"_ns
#define TO_DELETE_DIR_SUFFIX "-to_delete"_ns
#define BACKUP_DIR_SUFFIX "-backup"_ns
#define UPDATING_DIR_SUFFIX "-updating"_ns
#define V4_METADATA_SUFFIX ".metadata"_ns
#define V2_METADATA_SUFFIX ".sbstore"_ns
// The amount of time, in milliseconds, that our IO thread will stay alive after
// the last event it processes.
#define DEFAULT_THREAD_TIMEOUT_MS 5000
namespace mozilla {
namespace safebrowsing {
bool Classifier::OnUpdateThread() const {
bool onthread = false;
if (mUpdateThread) {
mUpdateThread->IsOnCurrentThread(&onthread);
}
return onthread;
}
void Classifier::SplitTables(const nsACString& str,
nsTArray<nsCString>& tables) {
tables.Clear();
for (const auto& table : str.Split(',')) {
if (!table.IsEmpty()) {
tables.AppendElement(table);
}
}
// Remove duplicates
tables.Sort();
const auto newEnd = std::unique(tables.begin(), tables.end());
tables.TruncateLength(std::distance(tables.begin(), newEnd));
}
nsresult Classifier::GetPrivateStoreDirectory(
nsIFile* aRootStoreDirectory, const nsACString& aTableName,
const nsACString& aProvider, nsIFile** aPrivateStoreDirectory) {
NS_ENSURE_ARG_POINTER(aPrivateStoreDirectory);
if (!StringEndsWith(aTableName, "-proto"_ns)) {
// Only V4 table names (ends with '-proto') would be stored
// to per-provider sub-directory.
nsCOMPtr<nsIFile>(aRootStoreDirectory).forget(aPrivateStoreDirectory);
return NS_OK;
}
if (aProvider.IsEmpty()) {
// When failing to get provider, just store in the root folder.
nsCOMPtr<nsIFile>(aRootStoreDirectory).forget(aPrivateStoreDirectory);
return NS_OK;
}
nsCOMPtr<nsIFile> providerDirectory;
// Clone first since we are gonna create a new directory.
nsresult rv = aRootStoreDirectory->Clone(getter_AddRefs(providerDirectory));
NS_ENSURE_SUCCESS(rv, rv);
// Append the provider name to the root store directory.
rv = providerDirectory->AppendNative(aProvider);
NS_ENSURE_SUCCESS(rv, rv);
// Ensure existence of the provider directory.
bool dirExists;
rv = providerDirectory->Exists(&dirExists);
NS_ENSURE_SUCCESS(rv, rv);
if (!dirExists) {
LOG(("Creating private directory for %s", nsCString(aTableName).get()));
rv = providerDirectory->Create(nsIFile::DIRECTORY_TYPE, 0755);
NS_ENSURE_SUCCESS(rv, rv);
providerDirectory.forget(aPrivateStoreDirectory);
return rv;
}
// Store directory exists. Check if it's a directory.
bool isDir;
rv = providerDirectory->IsDirectory(&isDir);
NS_ENSURE_SUCCESS(rv, rv);
if (!isDir) {
return NS_ERROR_FILE_DESTINATION_NOT_DIR;
}
providerDirectory.forget(aPrivateStoreDirectory);
return NS_OK;
}
Classifier::Classifier()
: mIsTableRequestResultOutdated(true),
mAsyncUpdateInProgress(false),
mUpdateInterrupted(true),
mIsClosed(false) {
// Make a lazy thread for any IO
mUpdateThread =
new LazyIdleThread(DEFAULT_THREAD_TIMEOUT_MS, "Classifier Update",
LazyIdleThread::ShutdownMethod::ManualShutdown);
}
Classifier::~Classifier() {
if (mUpdateThread) {
mUpdateThread->Shutdown();
mUpdateThread = nullptr;
}
Close();
}
nsresult Classifier::SetupPathNames() {
// Get the root directory where to store all the databases.
nsresult rv = mCacheDirectory->Clone(getter_AddRefs(mRootStoreDirectory));
NS_ENSURE_SUCCESS(rv, rv);
rv = mRootStoreDirectory->AppendNative(STORE_DIRECTORY);
NS_ENSURE_SUCCESS(rv, rv);
// Make sure LookupCaches (which are persistent and survive updates)
// are reading/writing in the right place. We will be moving their
// files "underneath" them during backup/restore.
for (uint32_t i = 0; i < mLookupCaches.Length(); i++) {
mLookupCaches[i]->UpdateRootDirHandle(mRootStoreDirectory);
}
// Directory where to move a backup before an update.
rv = mCacheDirectory->Clone(getter_AddRefs(mBackupDirectory));
NS_ENSURE_SUCCESS(rv, rv);
rv = mBackupDirectory->AppendNative(STORE_DIRECTORY + BACKUP_DIR_SUFFIX);
NS_ENSURE_SUCCESS(rv, rv);
// Directory where to be working on the update.
rv = mCacheDirectory->Clone(getter_AddRefs(mUpdatingDirectory));
NS_ENSURE_SUCCESS(rv, rv);
rv = mUpdatingDirectory->AppendNative(STORE_DIRECTORY + UPDATING_DIR_SUFFIX);
NS_ENSURE_SUCCESS(rv, rv);
// Directory where to move the backup so we can atomically
// delete (really move) it.
rv = mCacheDirectory->Clone(getter_AddRefs(mToDeleteDirectory));
NS_ENSURE_SUCCESS(rv, rv);
rv = mToDeleteDirectory->AppendNative(STORE_DIRECTORY + TO_DELETE_DIR_SUFFIX);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
nsresult Classifier::CreateStoreDirectory() {
if (ShouldAbort()) {
return NS_OK; // nothing to do, the classifier is done
}
// Ensure the safebrowsing directory exists.
bool storeExists;
nsresult rv = mRootStoreDirectory->Exists(&storeExists);
NS_ENSURE_SUCCESS(rv, rv);
if (!storeExists) {
rv = mRootStoreDirectory->Create(nsIFile::DIRECTORY_TYPE, 0755);
NS_ENSURE_SUCCESS(rv, rv);
} else {
bool storeIsDir;
rv = mRootStoreDirectory->IsDirectory(&storeIsDir);
NS_ENSURE_SUCCESS(rv, rv);
if (!storeIsDir) return NS_ERROR_FILE_DESTINATION_NOT_DIR;
}
return NS_OK;
}
// Testing entries are created directly in LookupCache instead of
// files from profile.
nsresult Classifier::ClearLegacyFiles() {
if (ShouldAbort()) {
return NS_OK; // nothing to do, the classifier is done
}
nsTArray<nsLiteralCString> tables = {
"test-phish-simple"_ns, "test-malware-simple"_ns,
"test-unwanted-simple"_ns, "test-harmful-simple"_ns,
"test-track-simple"_ns, "test-trackwhite-simple"_ns,
"test-block-simple"_ns,
};
const auto fnFindAndRemove = [](nsIFile* aRootDirectory,
const nsACString& aFileName) {
nsCOMPtr<nsIFile> file;
nsresult rv = aRootDirectory->Clone(getter_AddRefs(file));
if (NS_FAILED(rv)) {
return false;
}
rv = file->AppendNative(aFileName);
if (NS_FAILED(rv)) {
return false;
}
bool exists;
rv = file->Exists(&exists);
if (NS_FAILED(rv) || !exists) {
return false;
}
rv = file->Remove(false);
if (NS_FAILED(rv)) {
return false;
}
return true;
};
for (const auto& table : tables) {
// Remove both .sbstore and .vlpse if .sbstore exists
if (fnFindAndRemove(mRootStoreDirectory, table + ".sbstore"_ns)) {
fnFindAndRemove(mRootStoreDirectory, table + ".vlpset"_ns);
}
}
return NS_OK;
}
nsresult Classifier::Open(nsIFile& aCacheDirectory) {
// Remember the Local profile directory.
nsresult rv = aCacheDirectory.Clone(getter_AddRefs(mCacheDirectory));
NS_ENSURE_SUCCESS(rv, rv);
// Create the handles to the update and backup directories.
rv = SetupPathNames();
NS_ENSURE_SUCCESS(rv, rv);
// Clean up any to-delete directories that haven't been deleted yet.
// This is still required for backward compatibility.
rv = CleanToDelete();
NS_ENSURE_SUCCESS(rv, rv);
// If we met a crash during the previous update, "safebrowsing-updating"
// directory will exist and let's remove it.
rv = mUpdatingDirectory->Remove(true);
if (NS_SUCCEEDED(rv)) {
// If the "safebrowsing-updating" exists, it implies a crash occurred
// in the previous update.
LOG(("We may have hit a crash in the previous update."));
}
// Check whether we have an incomplete update and recover from the
// backup if so.
rv = RecoverBackups();
NS_ENSURE_SUCCESS(rv, rv);
// Make sure the main store directory exists.
rv = CreateStoreDirectory();
NS_ENSURE_SUCCESS(rv, rv);
rv = ClearLegacyFiles();
Unused << NS_WARN_IF(NS_FAILED(rv));
// Build the list of know urlclassifier lists
// XXX: Disk IO potentially on the main thread during startup
RegenActiveTables();
return NS_OK;
}
void Classifier::Close() {
// Close will be called by PreShutdown, so it is important to note that
// things put here should not affect an ongoing update thread.
mIsClosed = true;
DropStores();
}
void Classifier::Reset() {
MOZ_ASSERT(!OnUpdateThread(), "Reset() MUST NOT be called on update thread");
LOG(("Reset() is called so we interrupt the update."));
mUpdateInterrupted = true;
// We don't pass the ref counted object 'Classifier' to resetFunc because we
// don't want to release 'Classifier in the update thread, which triggers an
// assertion when LazyIdelUpdate thread is not created and removed by the same
// thread (worker thread). Since |resetFuc| is a synchronous call, we can just
// pass the reference of Classifier because Classifier's life cycle is
// guarantee longer than |resetFunc|.
auto resetFunc = [&] {
if (this->mIsClosed) {
return; // too late to reset, bail
}
this->DropStores();
this->mRootStoreDirectory->Remove(true);
this->mBackupDirectory->Remove(true);
this->mUpdatingDirectory->Remove(true);
this->mToDeleteDirectory->Remove(true);
this->CreateStoreDirectory();
this->RegenActiveTables();
};
if (!mUpdateThread) {
LOG(("Async update has been disabled. Just Reset() on worker thread."));
resetFunc();
return;
}
nsCOMPtr<nsIRunnable> r =
NS_NewRunnableFunction("safebrowsing::Classifier::Reset", resetFunc);
SyncRunnable::DispatchToThread(mUpdateThread, r);
}
void Classifier::ResetTables(ClearType aType,
const nsTArray<nsCString>& aTables) {
for (uint32_t i = 0; i < aTables.Length(); i++) {
LOG(("Resetting table: %s", aTables[i].get()));
RefPtr<LookupCache> cache = GetLookupCache(aTables[i]);
if (cache) {
// Remove any cached Completes for this table if clear type is Clear_Cache
if (aType == Clear_Cache) {
cache->ClearCache();
} else {
cache->ClearAll();
}
}
}
// Clear on-disk database if clear type is Clear_All
if (aType == Clear_All) {
DeleteTables(mRootStoreDirectory, aTables);
RegenActiveTables();
}
}
// |DeleteTables| is used by |GetLookupCache| to remove on-disk data when
// we detect prefix file corruption. So make sure not to call |GetLookupCache|
// again in this function to avoid infinite loop.
void Classifier::DeleteTables(nsIFile* aDirectory,
const nsTArray<nsCString>& aTables) {
nsCOMPtr<nsIDirectoryEnumerator> entries;
nsresult rv = aDirectory->GetDirectoryEntries(getter_AddRefs(entries));
NS_ENSURE_SUCCESS_VOID(rv);
nsCOMPtr<nsIFile> file;
while (NS_SUCCEEDED(rv = entries->GetNextFile(getter_AddRefs(file))) &&
file) {
// If |file| is a directory, recurse to find its entries as well.
bool isDirectory;
if (NS_FAILED(file->IsDirectory(&isDirectory))) {
continue;
}
if (isDirectory) {
DeleteTables(file, aTables);
continue;
}
nsCString leafName;
rv = file->GetNativeLeafName(leafName);
NS_ENSURE_SUCCESS_VOID(rv);
// Remove file extension if there's one.
int32_t dotPosition = leafName.RFind(".");
if (dotPosition >= 0) {
leafName.Truncate(dotPosition);
}
if (!leafName.IsEmpty() && aTables.Contains(leafName)) {
if (NS_FAILED(file->Remove(false))) {
NS_WARNING(nsPrintfCString("Fail to remove file %s from the disk",
leafName.get())
.get());
}
}
}
NS_ENSURE_SUCCESS_VOID(rv);
}
// This function is I/O intensive. It should only be called before applying
// an update.
void Classifier::TableRequest(nsACString& aResult) {
MOZ_ASSERT(!NS_IsMainThread(),
"TableRequest must be called on the classifier worker thread.");
// This function and all disk I/O are guaranteed to occur
// on the same thread so we don't need to add a lock around.
if (!mIsTableRequestResultOutdated) {
aResult = mTableRequestResult;
return;
}
// We reset tables failed to load here; not just tables are corrupted.
// It is because this is a safer way to ensure Safe Browsing databases
// can be recovered from any bad situations.
nsTArray<nsCString> failedTables;
// Load meta data from *.sbstore files in the root directory.
// Specifically for v4 tables.
nsCString v2Metadata;
nsresult rv = LoadHashStore(mRootStoreDirectory, v2Metadata, failedTables);
if (NS_SUCCEEDED(rv)) {
aResult.Append(v2Metadata);
}
// Load meta data from *.metadata files in the root directory.
// Specifically for v4 tables.
nsCString v4Metadata;
rv = LoadMetadata(mRootStoreDirectory, v4Metadata, failedTables);
if (NS_SUCCEEDED(rv)) {
aResult.Append(v4Metadata);
}
// Clear data for tables that we failed to open, a full update should
// be requested for those tables.
if (failedTables.Length() != 0) {
LOG(("Reset tables failed to open before applying an update"));
ResetTables(Clear_All, failedTables);
}
// Update the TableRequest result in-memory cache.
mTableRequestResult = aResult;
mIsTableRequestResultOutdated = false;
}
nsresult Classifier::CheckURIFragments(
const nsTArray<nsCString>& aSpecFragments, const nsACString& aTable,
LookupResultArray& aResults) {
// A URL can form up to 30 different fragments
MOZ_ASSERT(aSpecFragments.Length() != 0);
MOZ_ASSERT(aSpecFragments.Length() <=
(MAX_HOST_COMPONENTS * (MAX_PATH_COMPONENTS + 2)));
if (LOG_ENABLED()) {
uint32_t urlIdx = 0;
for (uint32_t i = 1; i < aSpecFragments.Length(); i++) {
if (aSpecFragments[urlIdx].Length() < aSpecFragments[i].Length()) {
urlIdx = i;
}
}
LOG(("Checking table %s, URL is %s", aTable.BeginReading(),
aSpecFragments[urlIdx].get()));
}
RefPtr<LookupCache> cache = GetLookupCache(aTable);
if (NS_WARN_IF(!cache)) {
return NS_ERROR_FAILURE;
}
// Now check each lookup fragment against the entries in the DB.
for (uint32_t i = 0; i < aSpecFragments.Length(); i++) {
Completion lookupHash;
lookupHash.FromPlaintext(aSpecFragments[i]);
bool has, confirmed;
uint32_t matchLength;
nsresult rv = cache->Has(lookupHash, &has, &matchLength, &confirmed);
NS_ENSURE_SUCCESS(rv, rv);
if (has) {
RefPtr<LookupResult> result = new LookupResult;
aResults.AppendElement(result);
if (LOG_ENABLED()) {
nsAutoCString checking;
lookupHash.ToHexString(checking);
LOG(("Found a result in fragment %s, hash %s (%X)",
aSpecFragments[i].get(), checking.get(), lookupHash.ToUint32()));
LOG(("Result %s, match %d-bytes prefix",
confirmed ? "confirmed." : "Not confirmed.", matchLength));
}
result->hash.complete = lookupHash;
result->mConfirmed = confirmed;
result->mTableName.Assign(cache->TableName());
result->mPartialHashLength = confirmed ? COMPLETE_SIZE : matchLength;
result->mProtocolV2 = LookupCache::Cast<LookupCacheV2>(cache);
}
}
return NS_OK;
}
static nsresult SwapDirectoryContent(nsIFile* aDir1, nsIFile* aDir2,
nsIFile* aParentDir, nsIFile* aTempDir) {
// Pre-condition: |aDir1| and |aDir2| are directory and their parent
// are both |aParentDir|.
//
// Post-condition: The locations where aDir1 and aDir2 point to will not
// change but their contents will be exchanged. If we failed
// to swap their content, everything will be rolled back.
nsAutoCString tempDirName;
aTempDir->GetNativeLeafName(tempDirName);
nsresult rv;
nsAutoCString dirName1, dirName2;
aDir1->GetNativeLeafName(dirName1);
aDir2->GetNativeLeafName(dirName2);
LOG(("Swapping directories %s and %s...", dirName1.get(), dirName2.get()));
// 1. Rename "dirName1" to "temp"
rv = aDir1->RenameToNative(nullptr, tempDirName);
if (NS_FAILED(rv)) {
LOG(("Unable to rename %s to %s", dirName1.get(), tempDirName.get()));
return rv; // Nothing to roll back.
}
// 1.1. Create a handle for temp directory. This is required since
// |nsIFile.rename| will not change the location where the
// object points to.
nsCOMPtr<nsIFile> tempDirectory;
rv = aParentDir->Clone(getter_AddRefs(tempDirectory));
rv = tempDirectory->AppendNative(tempDirName);
// 2. Rename "dirName2" to "dirName1".
rv = aDir2->RenameToNative(nullptr, dirName1);
if (NS_FAILED(rv)) {
LOG(("Failed to rename %s to %s. Rename temp directory back to %s",
dirName2.get(), dirName1.get(), dirName1.get()));
nsresult rbrv = tempDirectory->RenameToNative(nullptr, dirName1);
NS_ENSURE_SUCCESS(rbrv, rbrv);
return rv;
}
// 3. Rename "temp" to "dirName2".
rv = tempDirectory->RenameToNative(nullptr, dirName2);
if (NS_FAILED(rv)) {
LOG(("Failed to rename temp directory to %s. ", dirName2.get()));
// We've done (1) renaming "dir1 to temp" and
// (2) renaming "dir2 to dir1"
// so the rollback is
// (1) renaming "dir1 to dir2" and
// (2) renaming "temp to dir1"
nsresult rbrv; // rollback result
rbrv = aDir1->RenameToNative(nullptr, dirName2);
NS_ENSURE_SUCCESS(rbrv, rbrv);
rbrv = tempDirectory->RenameToNative(nullptr, dirName1);
NS_ENSURE_SUCCESS(rbrv, rbrv);
return rv;
}
return rv;
}
void Classifier::RemoveUpdateIntermediaries() {
// Remove old LookupCaches.
mNewLookupCaches.Clear();
// Remove the "old" directory. (despite its looking-new name)
if (NS_FAILED(mUpdatingDirectory->Remove(true))) {
// If the directory is locked from removal for some reason,
// we will fail here and it doesn't matter until the next
// update. (the next udpate will fail due to the removable
// "safebrowsing-udpating" directory.)
LOG(("Failed to remove updating directory."));
}
}
void Classifier::CopyAndInvalidateFullHashCache() {
MOZ_ASSERT(!OnUpdateThread(),
"CopyAndInvalidateFullHashCache cannot be called on update thread "
"since it mutates mLookupCaches which is only safe on "
"worker thread.");
// New lookup caches are built from disk, data likes cache which is
// generated online won't exist. We have to manually copy cache from
// old LookupCache to new LookupCache.
for (auto& newCache : mNewLookupCaches) {
for (auto& oldCache : mLookupCaches) {
if (oldCache->TableName() == newCache->TableName()) {
newCache->CopyFullHashCache(oldCache);
break;
}
}
}
// Clear cache when update.
// Invalidate cache entries in CopyAndInvalidateFullHashCache because only
// at this point we will have cache data in LookupCache.
for (auto& newCache : mNewLookupCaches) {
newCache->InvalidateExpiredCacheEntries();
}
}
void Classifier::MergeNewLookupCaches() {
MOZ_ASSERT(!OnUpdateThread(),
"MergeNewLookupCaches cannot be called on update thread "
"since it mutates mLookupCaches which is only safe on "
"worker thread.");
for (auto& newCache : mNewLookupCaches) {
// For each element in mNewLookCaches, it will be swapped with
// - An old cache in mLookupCache with the same table name or
// - nullptr (mLookupCache will be expaned) otherwise.
size_t swapIndex = 0;
for (; swapIndex < mLookupCaches.Length(); swapIndex++) {
if (mLookupCaches[swapIndex]->TableName() == newCache->TableName()) {
break;
}
}
if (swapIndex == mLookupCaches.Length()) {
mLookupCaches.AppendElement(nullptr);
}
std::swap(mLookupCaches[swapIndex], newCache);
mLookupCaches[swapIndex]->UpdateRootDirHandle(mRootStoreDirectory);
}
// At this point, mNewLookupCaches's length remains the same but
// will contain either old cache (override) or nullptr (append).
}
nsresult Classifier::SwapInNewTablesAndCleanup() {
nsresult rv;
// Step 1. Swap in on-disk tables. The idea of using "safebrowsing-backup"
// as the intermediary directory is we can get databases recovered if
// crash occurred in any step of the swap. (We will recover from
// "safebrowsing-backup" in OpenDb().)
rv = SwapDirectoryContent(mUpdatingDirectory, // contains new tables
mRootStoreDirectory, // contains old tables
mCacheDirectory, // common parent dir
mBackupDirectory); // intermediary dir for swap
if (NS_FAILED(rv)) {
LOG(("Failed to swap in on-disk tables."));
RemoveUpdateIntermediaries();
return rv;
}
// Step 2. Merge mNewLookupCaches into mLookupCaches. The outdated
// LookupCaches will be stored in mNewLookupCaches and be cleaned
// up later.
MergeNewLookupCaches();
// Step 3. Re-generate active tables based on on-disk tables.
rv = RegenActiveTables();
if (NS_FAILED(rv)) {
LOG(("Failed to re-generate active tables!"));
}
// Step 4. Clean up intermediaries for update.
RemoveUpdateIntermediaries();
// Step 5. Invalidate cached tableRequest request.
mIsTableRequestResultOutdated = true;
LOG(("Done swap in updated tables."));
return rv;
}
void Classifier::FlushAndDisableAsyncUpdate() {
LOG(("Classifier::FlushAndDisableAsyncUpdate [%p, %p]", this,
mUpdateThread.get()));
if (!mUpdateThread) {
LOG(("Async update has been disabled."));
return;
}
mUpdateThread->Shutdown();
mUpdateThread = nullptr;
mPendingUpdates.Clear();
mAsyncUpdateInProgress = false;
}
nsresult Classifier::AsyncApplyUpdates(const TableUpdateArray& aUpdates,
const AsyncUpdateCallback& aCallback) {
LOG(("Classifier::AsyncApplyUpdates"));
if (!mUpdateThread) {
LOG(("Async update has already been disabled."));
return NS_ERROR_FAILURE;
}
if (mAsyncUpdateInProgress) {
mPendingUpdates.AppendElement(NS_NewRunnableFunction(
"safebrowsing::Classifier::AsyncApplyUpdates",
[self = RefPtr{this}, aUpdates = aUpdates.Clone(),
aCallback]() mutable {
nsresult rv = self->AsyncApplyUpdates(aUpdates, aCallback);
// Calling the callback if we got an failure here to notify update
// observers.
if (NS_FAILED(rv)) {
aCallback(rv);
}
}));
return NS_OK;
}
// Caller thread | Update thread
// --------------------------------------------------------
// | ApplyUpdatesBackground
// (processing other task) | (bg-update done. ping back to caller
// thread) (processing other task) | idle... ApplyUpdatesForeground |
// callback |
MOZ_ASSERT(mNewLookupCaches.IsEmpty(),
"There should be no leftovers from a previous update.");
mAsyncUpdateInProgress = true;
mUpdateInterrupted = false;
nsresult rv =
mRootStoreDirectory->Clone(getter_AddRefs(mRootStoreDirectoryForUpdate));
if (NS_FAILED(rv)) {
LOG(("Failed to clone mRootStoreDirectory for update."));
return rv;
}
nsCOMPtr<nsIThread> callerThread = NS_GetCurrentThread();
MOZ_ASSERT(!OnUpdateThread());
RefPtr<Classifier> self = this;
nsCOMPtr<nsIRunnable> bgRunnable = NS_NewRunnableFunction(
"safebrowsing::Classifier::AsyncApplyUpdates",
[self, aUpdates = aUpdates.Clone(), aCallback, callerThread]() mutable {
MOZ_ASSERT(self->OnUpdateThread(), "MUST be on update thread");
nsresult bgRv;
nsTArray<nsCString> failedTableNames;
TableUpdateArray updates;
// Make a copy of the array since we'll be removing entries as
// we process them on the background thread.
if (updates.AppendElements(std::move(aUpdates), fallible)) {
LOG(("Step 1. ApplyUpdatesBackground on update thread."));
bgRv = self->ApplyUpdatesBackground(updates, failedTableNames);
} else {
LOG(
("Step 1. Not enough memory to run ApplyUpdatesBackground on "
"update thread."));
bgRv = NS_ERROR_OUT_OF_MEMORY;
}
// Classifier is created in the worker thread and it has to be released
// in the worker thread(because of the constrain that LazyIdelThread has
// to be created and released in the same thread). We transfer the
// ownership to the caller thread here to gurantee that we don't release
// it in the udpate thread.
nsCOMPtr<nsIRunnable> fgRunnable = NS_NewRunnableFunction(
"safebrowsing::Classifier::AsyncApplyUpdates",
[self = std::move(self), aCallback, bgRv,
failedTableNames = std::move(failedTableNames),
callerThread]() mutable {
RefPtr<Classifier> classifier = std::move(self);
MOZ_ASSERT(NS_GetCurrentThread() == callerThread,
"MUST be on caller thread");
LOG(("Step 2. ApplyUpdatesForeground on caller thread"));
nsresult rv =
classifier->ApplyUpdatesForeground(bgRv, failedTableNames);
LOG(("Step 3. Updates applied! Fire callback."));
aCallback(rv);
classifier->AsyncUpdateFinished();
});
callerThread->Dispatch(fgRunnable, NS_DISPATCH_NORMAL);
});
return mUpdateThread->Dispatch(bgRunnable, NS_DISPATCH_NORMAL);
}
void Classifier::AsyncUpdateFinished() {
MOZ_ASSERT(!OnUpdateThread(),
"AsyncUpdateFinished() MUST NOT be called on update thread");
MOZ_ASSERT(!NS_IsMainThread(),
"AsyncUpdateFinished() must be called on the worker thread");
mAsyncUpdateInProgress = false;
// If there are pending updates, run the first one.
if (!mPendingUpdates.IsEmpty()) {
auto& runnable = mPendingUpdates.ElementAt(0);
runnable->Run();
mPendingUpdates.RemoveElementAt(0);
}
}
nsresult Classifier::ApplyUpdatesBackground(
TableUpdateArray& aUpdates, nsTArray<nsCString>& aFailedTableNames) {
// |mUpdateInterrupted| is guaranteed to have been unset.
// If |mUpdateInterrupted| is set at any point, Reset() must have
// been called then we need to interrupt the update process.
// We only add checkpoints for non-trivial tasks.
if (aUpdates.IsEmpty()) {
return NS_OK;
}
nsUrlClassifierUtils* urlUtil = nsUrlClassifierUtils::GetInstance();
if (NS_WARN_IF(!urlUtil)) {
return NS_ERROR_FAILURE;
}
nsCString provider;
// Assume all TableUpdate objects should have the same provider.
urlUtil->GetTelemetryProvider(aUpdates[0]->TableName(), provider);
Telemetry::AutoTimer<Telemetry::URLCLASSIFIER_CL_KEYED_UPDATE_TIME>
keyedTimer(provider);
PRIntervalTime clockStart = 0;
if (LOG_ENABLED()) {
clockStart = PR_IntervalNow();
}
nsresult rv;
// Check point 1: Copying files takes time so we check ShouldAbort()
// inside CopyInUseDirForUpdate().
rv = CopyInUseDirForUpdate(); // i.e. mUpdatingDirectory will be setup.
if (NS_FAILED(rv)) {
LOG(("Failed to copy in-use directory for update."));
return (rv == NS_ERROR_ABORT) ? NS_OK : rv;
}
LOG(("Applying %zu table updates.", aUpdates.Length()));
for (uint32_t i = 0; i < aUpdates.Length(); i++) {
RefPtr<const TableUpdate> update = aUpdates[i];
if (!update) {
// Previous UpdateHashStore() may have consumed this update..
continue;
}
// Run all updates for one table
nsAutoCString updateTable(update->TableName());
// Check point 2: Processing downloaded data takes time.
if (ShouldAbort()) {
LOG(("Update is interrupted. Stop building new tables."));
return NS_OK;
}
// Will update the mirrored in-memory and on-disk databases.
if (TableUpdate::Cast<TableUpdateV2>(update)) {
rv = UpdateHashStore(aUpdates, updateTable);
} else {
rv = UpdateTableV4(aUpdates, updateTable);
}
if (NS_WARN_IF(NS_FAILED(rv))) {
LOG(("Failed to update table: %s", updateTable.get()));
// We don't quit the updating process immediately when we discover
// a failure. Instead, we continue to apply updates to the
// remaining tables to find other tables which may also fail to
// apply an update. This help us reset all the corrupted tables
// within a single update.
// Note that changes that result from successful updates don't take
// effect after the updating process is finished. This is because
// when an error occurs during the updating process, we ignore all
// changes that have happened during the udpating process.
aFailedTableNames.AppendElement(updateTable);
continue;
}
}
if (!aFailedTableNames.IsEmpty()) {
RemoveUpdateIntermediaries();
return NS_ERROR_FAILURE;
}
if (LOG_ENABLED()) {
PRIntervalTime clockEnd = PR_IntervalNow();
LOG(("update took %dms\n",
PR_IntervalToMilliseconds(clockEnd - clockStart)));
}
return rv;
}
nsresult Classifier::ApplyUpdatesForeground(
nsresult aBackgroundRv, const nsTArray<nsCString>& aFailedTableNames) {
if (ShouldAbort()) {
LOG(("Update is interrupted! Just remove update intermediaries."));
RemoveUpdateIntermediaries();
return NS_OK;
}
if (NS_SUCCEEDED(aBackgroundRv)) {
// Copy and Invalidate fullhash cache here because this call requires
// mLookupCaches which is only available on work-thread
CopyAndInvalidateFullHashCache();
return SwapInNewTablesAndCleanup();
}
if (NS_ERROR_OUT_OF_MEMORY != aBackgroundRv) {
ResetTables(Clear_All, aFailedTableNames);
}
return aBackgroundRv;
}
nsresult Classifier::ApplyFullHashes(ConstTableUpdateArray& aUpdates) {
MOZ_ASSERT(!OnUpdateThread(),
"ApplyFullHashes() MUST NOT be called on update thread");
MOZ_ASSERT(
!NS_IsMainThread(),
"ApplyFullHashes() must be called on the classifier worker thread.");
LOG(("Applying %zu table gethashes.", aUpdates.Length()));
for (uint32_t i = 0; i < aUpdates.Length(); i++) {
nsresult rv = UpdateCache(aUpdates[i]);
NS_ENSURE_SUCCESS(rv, rv);
aUpdates[i] = nullptr;
}
return NS_OK;
}
void Classifier::GetCacheInfo(const nsACString& aTable,
nsIUrlClassifierCacheInfo** aCache) {
RefPtr<const LookupCache> lookupCache = GetLookupCache(aTable);
if (!lookupCache) {
return;
}
lookupCache->GetCacheInfo(aCache);
}
void Classifier::DropStores() {
// See the comment in Classifier::Close() before adding anything here.
mLookupCaches.Clear();
}
nsresult Classifier::RegenActiveTables() {
if (ShouldAbort()) {
return NS_OK; // nothing to do, the classifier is done
}
mActiveTablesCache.Clear();
// The extension of V2 and V4 prefix files is .vlpset
// We still check .pset here for legacy load.
nsTArray<nsCString> exts = {".vlpset"_ns, ".pset"_ns};
nsTArray<nsCString> foundTables;
nsresult rv = ScanStoreDir(mRootStoreDirectory, exts, foundTables);
Unused << NS_WARN_IF(NS_FAILED(rv));
// We don't have test tables on disk, add Moz built-in entries here
rv = AddMozEntries(foundTables);
Unused << NS_WARN_IF(NS_FAILED(rv));
for (const auto& table : foundTables) {
RefPtr<const LookupCache> lookupCache = GetLookupCache(table);
if (!lookupCache) {
LOG(("Inactive table (no cache): %s", table.get()));
continue;
}
if (!lookupCache->IsPrimed()) {
LOG(("Inactive table (cache not primed): %s", table.get()));
continue;
}
LOG(("Active %s table: %s",
LookupCache::Cast<const LookupCacheV4>(lookupCache) ? "v4" : "v2",
table.get()));
mActiveTablesCache.AppendElement(table);
}
return NS_OK;
}
nsresult Classifier::AddMozEntries(nsTArray<nsCString>& aTables) {
nsTArray<nsLiteralCString> tables = {
"moztest-phish-simple"_ns, "moztest-malware-simple"_ns,
"moztest-unwanted-simple"_ns, "moztest-harmful-simple"_ns,
"moztest-track-simple"_ns, "moztest-trackwhite-simple"_ns,
"moztest-block-simple"_ns,
};
for (const auto& table : tables) {
RefPtr<LookupCache> c = GetLookupCache(table, false);
RefPtr<LookupCacheV2> lookupCache = LookupCache::Cast<LookupCacheV2>(c);
if (!lookupCache || lookupCache->IsPrimed()) {
continue;
}
aTables.AppendElement(table);
}
return NS_OK;
}
nsresult Classifier::ScanStoreDir(nsIFile* aDirectory,
const nsTArray<nsCString>& aExtensions,
nsTArray<nsCString>& aTables) {
nsCOMPtr<nsIDirectoryEnumerator> entries;
nsresult rv = aDirectory->GetDirectoryEntries(getter_AddRefs(entries));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIFile> file;
while (NS_SUCCEEDED(rv = entries->GetNextFile(getter_AddRefs(file))) &&
file) {
// If |file| is a directory, recurse to find its entries as well.
bool isDirectory;
if (NS_FAILED(file->IsDirectory(&isDirectory))) {
continue;
}
if (isDirectory) {
ScanStoreDir(file, aExtensions, aTables);
continue;
}
nsAutoCString leafName;
rv = file->GetNativeLeafName(leafName);
NS_ENSURE_SUCCESS(rv, rv);
for (const auto& ext : aExtensions) {
if (StringEndsWith(leafName, ext)) {
aTables.AppendElement(
Substring(leafName, 0, leafName.Length() - strlen(ext.get())));
break;
}
}
}
return NS_OK;
}
nsresult Classifier::ActiveTables(nsTArray<nsCString>& aTables) const {
aTables = mActiveTablesCache.Clone();
return NS_OK;
}
nsresult Classifier::CleanToDelete() {
bool exists;
nsresult rv = mToDeleteDirectory->Exists(&exists);
NS_ENSURE_SUCCESS(rv, rv);
if (exists) {
rv = mToDeleteDirectory->Remove(true);
NS_ENSURE_SUCCESS(rv, rv);
}
return NS_OK;
}
/**
* This function copies the files one by one to the destination folder.
* Before copying a file, it checks ::ShouldAbort and returns
* NS_ERROR_ABORT if the flag is set.
*/
nsresult Classifier::CopyDirectoryInterruptible(nsCOMPtr<nsIFile>& aDestDir,
nsCOMPtr<nsIFile>& aSourceDir) {
nsCOMPtr<nsIDirectoryEnumerator> entries;
nsresult rv = aSourceDir->GetDirectoryEntries(getter_AddRefs(entries));
NS_ENSURE_SUCCESS(rv, rv);
MOZ_ASSERT(entries);
nsCOMPtr<nsIFile> source;
while (NS_SUCCEEDED(rv = entries->GetNextFile(getter_AddRefs(source))) &&
source) {
if (ShouldAbort()) {
LOG(("Update is interrupted. Aborting the directory copy"));
return NS_ERROR_ABORT;
}
bool isDirectory;
rv = source->IsDirectory(&isDirectory);
NS_ENSURE_SUCCESS(rv, rv);
if (isDirectory) {
// If it is a directory, recursively copy the files inside the directory.
nsAutoCString leaf;
source->GetNativeLeafName(leaf);
MOZ_ASSERT(!leaf.IsEmpty());
nsCOMPtr<nsIFile> dest;
aDestDir->Clone(getter_AddRefs(dest));
dest->AppendNative(leaf);
NS_ENSURE_SUCCESS(rv, rv);
rv = CopyDirectoryInterruptible(dest, source);
NS_ENSURE_SUCCESS(rv, rv);
} else {
rv = source->CopyToNative(aDestDir, ""_ns);
NS_ENSURE_SUCCESS(rv, rv);
}
}
// If the destination directory doesn't exist in the end, it means that the
// source directory is empty, we should copy the directory here.
bool exist;
rv = aDestDir->Exists(&exist);
NS_ENSURE_SUCCESS(rv, rv);
if (!exist) {
rv = aDestDir->Create(nsIFile::DIRECTORY_TYPE, 0755);
NS_ENSURE_SUCCESS(rv, rv);
}
return NS_OK;
}
nsresult Classifier::CopyInUseDirForUpdate() {
LOG(("Copy in-use directory content for update."));
if (ShouldAbort()) {
return NS_ERROR_UC_UPDATE_SHUTDOWNING;
}
// We copy everything from in-use directory to a temporary directory
// for updating.
// Remove the destination directory first (just in case) the do the copy.
mUpdatingDirectory->Remove(true);
if (!mRootStoreDirectoryForUpdate) {
LOG(("mRootStoreDirectoryForUpdate is null."));
return NS_ERROR_NULL_POINTER;
}
nsresult rv = CopyDirectoryInterruptible(mUpdatingDirectory,
mRootStoreDirectoryForUpdate);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
nsresult Classifier::RecoverBackups() {
bool backupExists;
nsresult rv = mBackupDirectory->Exists(&backupExists);
NS_ENSURE_SUCCESS(rv, rv);
if (backupExists) {
// Remove the safebrowsing dir if it exists
nsCString storeDirName;
rv = mRootStoreDirectory->GetNativeLeafName(storeDirName);
NS_ENSURE_SUCCESS(rv, rv);
bool storeExists;
rv = mRootStoreDirectory->Exists(&storeExists);
NS_ENSURE_SUCCESS(rv, rv);
if (storeExists) {
rv = mRootStoreDirectory->Remove(true);
NS_ENSURE_SUCCESS(rv, rv);
}
// Move the backup to the store location
rv = mBackupDirectory->MoveToNative(nullptr, storeDirName);
NS_ENSURE_SUCCESS(rv, rv);
// mBackupDirectory now points to storeDir, fix up.
rv = SetupPathNames();
NS_ENSURE_SUCCESS(rv, rv);
}
return NS_OK;
}
bool Classifier::CheckValidUpdate(TableUpdateArray& aUpdates,
const nsACString& aTable) {
// take the quick exit if there is no valid update for us
// (common case)
uint32_t validupdates = 0;
for (uint32_t i = 0; i < aUpdates.Length(); i++) {
RefPtr<const TableUpdate> update = aUpdates[i];
if (!update || !update->TableName().Equals(aTable)) {
continue;
}
if (update->Empty()) {
aUpdates[i] = nullptr;
continue;
}
validupdates++;
}
if (!validupdates) {
// This can happen if the update was only valid for one table.
return false;
}
return true;
}
nsCString Classifier::GetProvider(const nsACString& aTableName) {
nsUrlClassifierUtils* urlUtil = nsUrlClassifierUtils::GetInstance();
if (NS_WARN_IF(!urlUtil)) {
return ""_ns;
}
nsCString provider;
nsresult rv = urlUtil->GetProvider(aTableName, provider);
return NS_SUCCEEDED(rv) ? provider : ""_ns;
}
/*
* This will consume+delete updates from the passed nsTArray.
*/
nsresult Classifier::UpdateHashStore(TableUpdateArray& aUpdates,
const nsACString& aTable) {
if (ShouldAbort()) {
return NS_ERROR_UC_UPDATE_SHUTDOWNING;
}
LOG(("Classifier::UpdateHashStore(%s)", PromiseFlatCString(aTable).get()));
// moztest- tables don't support update because they are directly created
// in LookupCache. To test updates, use tables begin with "test-" instead.
// Also, recommend using 'test-' tables while writing testcases because
// it is more like the real world scenario.
MOZ_ASSERT(!nsUrlClassifierUtils::IsMozTestTable(aTable));
HashStore store(aTable, GetProvider(aTable), mUpdatingDirectory);
if (!CheckValidUpdate(aUpdates, store.TableName())) {
return NS_OK;
}
nsresult rv = store.Open();
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
rv = store.BeginUpdate();
NS_ENSURE_SUCCESS(rv, rv);
// Read the part of the store that is (only) in the cache
RefPtr<LookupCacheV2> lookupCacheV2;
{
RefPtr<LookupCache> lookupCache =
GetLookupCacheForUpdate(store.TableName());
if (lookupCache) {
lookupCacheV2 = LookupCache::Cast<LookupCacheV2>(lookupCache);
}
}
if (!lookupCacheV2) {
return NS_ERROR_UC_UPDATE_TABLE_NOT_FOUND;
}
FallibleTArray<uint32_t> AddPrefixHashes;
FallibleTArray<nsCString> AddCompletesHashes;
rv = lookupCacheV2->GetPrefixes(AddPrefixHashes, AddCompletesHashes);
NS_ENSURE_SUCCESS(rv, rv);
rv = store.AugmentAdds(AddPrefixHashes, AddCompletesHashes);
NS_ENSURE_SUCCESS(rv, rv);
AddPrefixHashes.Clear();
AddCompletesHashes.Clear();
uint32_t applied = 0;
for (uint32_t i = 0; i < aUpdates.Length(); i++) {
RefPtr<TableUpdate> update = aUpdates[i];
if (!update || !update->TableName().Equals(store.TableName())) {
continue;
}
RefPtr<TableUpdateV2> updateV2 = TableUpdate::Cast<TableUpdateV2>(update);
NS_ENSURE_TRUE(updateV2, NS_ERROR_UC_UPDATE_UNEXPECTED_VERSION);
rv = store.ApplyUpdate(updateV2);
NS_ENSURE_SUCCESS(rv, rv);
applied++;
LOG(("Applied update to table %s:", store.TableName().get()));
LOG((" %d add chunks", updateV2->AddChunks().Length()));
LOG((" %zu add prefixes", updateV2->AddPrefixes().Length()));
LOG((" %zu add completions", updateV2->AddCompletes().Length()));
LOG((" %d sub chunks", updateV2->SubChunks().Length()));
LOG((" %zu sub prefixes", updateV2->SubPrefixes().Length()));
LOG((" %zu sub completions", updateV2->SubCompletes().Length()));
LOG((" %d add expirations", updateV2->AddExpirations().Length()));
LOG((" %d sub expirations", updateV2->SubExpirations().Length()));
aUpdates[i] = nullptr;
}
LOG(("Applied %d update(s) to %s.", applied, store.TableName().get()));
rv = store.Rebuild();
NS_ENSURE_SUCCESS(rv, rv);
LOG(("Table %s now has:", store.TableName().get()));
LOG((" %d add chunks", store.AddChunks().Length()));
LOG((" %zu add prefixes", store.AddPrefixes().Length()));
LOG((" %zu add completions", store.AddCompletes().Length()));
LOG((" %d sub chunks", store.SubChunks().Length()));
LOG((" %zu sub prefixes", store.SubPrefixes().Length()));
LOG((" %zu sub completions", store.SubCompletes().Length()));
rv = store.WriteFile();
NS_ENSURE_SUCCESS(rv, rv);
// At this point the store is updated and written out to disk, but
// the data is still in memory. Build our quick-lookup table here.
rv = lookupCacheV2->Build(store.AddPrefixes(), store.AddCompletes());
NS_ENSURE_SUCCESS(rv, NS_ERROR_UC_UPDATE_BUILD_PREFIX_FAILURE);
rv = lookupCacheV2->WriteFile();
NS_ENSURE_SUCCESS(rv, NS_ERROR_UC_UPDATE_FAIL_TO_WRITE_DISK);
LOG(("Successfully updated %s", store.TableName().get()));
return NS_OK;
}
nsresult Classifier::UpdateTableV4(TableUpdateArray& aUpdates,
const nsACString& aTable) {
MOZ_ASSERT(!NS_IsMainThread(),
"UpdateTableV4 must be called on the classifier worker thread.");
if (ShouldAbort()) {
return NS_ERROR_UC_UPDATE_SHUTDOWNING;
}
// moztest- tables don't support update, see comment in UpdateHashStore.
MOZ_ASSERT(!nsUrlClassifierUtils::IsMozTestTable(aTable));
LOG(("Classifier::UpdateTableV4(%s)", PromiseFlatCString(aTable).get()));
if (!CheckValidUpdate(aUpdates, aTable)) {
return NS_OK;
}
RefPtr<LookupCacheV4> lookupCacheV4;
{
RefPtr<LookupCache> lookupCache = GetLookupCacheForUpdate(aTable);
if (lookupCache) {
lookupCacheV4 = LookupCache::Cast<LookupCacheV4>(lookupCache);
}
}
if (!lookupCacheV4) {
return NS_ERROR_UC_UPDATE_TABLE_NOT_FOUND;
}
nsresult rv = NS_OK;
// If there are multiple updates for the same table, prefixes1 & prefixes2
// will act as input and output in turn to reduce memory copy overhead.
PrefixStringMap prefixes1, prefixes2;
PrefixStringMap* input = &prefixes1;
PrefixStringMap* output = &prefixes2;
RefPtr<const TableUpdateV4> lastAppliedUpdate = nullptr;
for (uint32_t i = 0; i < aUpdates.Length(); i++) {
RefPtr<TableUpdate> update = aUpdates[i];
if (!update || !update->TableName().Equals(aTable)) {
continue;
}
RefPtr<TableUpdateV4> updateV4 = TableUpdate::Cast<TableUpdateV4>(update);
NS_ENSURE_TRUE(updateV4, NS_ERROR_UC_UPDATE_UNEXPECTED_VERSION);
if (updateV4->IsFullUpdate()) {
input->Clear();
output->Clear();
rv = lookupCacheV4->ApplyUpdate(updateV4, *input, *output);
if (NS_FAILED(rv)) {
return rv;
}
} else {
// If both prefix sets are empty, this means we are doing a partial update
// without a prior full/partial update in the loop. In this case we should
// get prefixes from the lookup cache first.
if (prefixes1.IsEmpty() && prefixes2.IsEmpty()) {
lookupCacheV4->GetPrefixes(prefixes1);
// issue.
rv = lookupCacheV4->ApplyUpdate(updateV4, *input, *output);
} else {
MOZ_ASSERT(prefixes1.IsEmpty() ^ prefixes2.IsEmpty());
// When there are multiple partial updates, input should always point
// to the non-empty prefix set(filled by previous full/partial update).
// output should always point to the empty prefix set.
input = prefixes1.IsEmpty() ? &prefixes2 : &prefixes1;
output = prefixes1.IsEmpty() ? &prefixes1 : &prefixes2;
// issue.
rv = lookupCacheV4->ApplyUpdate(updateV4, *input, *output);
}
if (NS_FAILED(rv)) {
return rv;
}
input->Clear();
}
// Keep track of the last applied update.
lastAppliedUpdate = updateV4;
aUpdates[i] = nullptr;
}
rv = lookupCacheV4->Build(*output);
NS_ENSURE_SUCCESS(rv, NS_ERROR_UC_UPDATE_BUILD_PREFIX_FAILURE);
rv = lookupCacheV4->WriteFile();
NS_ENSURE_SUCCESS(rv, NS_ERROR_UC_UPDATE_FAIL_TO_WRITE_DISK);
if (lastAppliedUpdate) {
LOG(("Write meta data of the last applied update."));
rv = lookupCacheV4->WriteMetadata(lastAppliedUpdate);
NS_ENSURE_SUCCESS(rv, NS_ERROR_UC_UPDATE_FAIL_TO_WRITE_DISK);
}
LOG(("Successfully updated %s\n", PromiseFlatCString(aTable).get()));
return NS_OK;
}
nsresult Classifier::UpdateCache(RefPtr<const TableUpdate> aUpdate) {
if (!aUpdate) {
return NS_OK;
}
nsAutoCString table(aUpdate->TableName());
LOG(("Classifier::UpdateCache(%s)", table.get()));
RefPtr<LookupCache> lookupCache = GetLookupCache(table);
if (!lookupCache) {
return NS_ERROR_FAILURE;
}
RefPtr<LookupCacheV2> lookupV2 =
LookupCache::Cast<LookupCacheV2>(lookupCache);
if (lookupV2) {
RefPtr<const TableUpdateV2> updateV2 =
TableUpdate::Cast<TableUpdateV2>(aUpdate);
lookupV2->AddGethashResultToCache(updateV2->AddCompletes(),
updateV2->MissPrefixes());
} else {
RefPtr<LookupCacheV4> lookupV4 =
LookupCache::Cast<LookupCacheV4>(lookupCache);
if (!lookupV4) {
return NS_ERROR_FAILURE;
}
RefPtr<const TableUpdateV4> updateV4 =
TableUpdate::Cast<TableUpdateV4>(aUpdate);
lookupV4->AddFullHashResponseToCache(updateV4->FullHashResponse());
}
#if defined(DEBUG)
lookupCache->DumpCache();
#endif
return NS_OK;
}
RefPtr<LookupCache> Classifier::GetLookupCache(const nsACString& aTable,
bool aForUpdate) {
// GetLookupCache(aForUpdate==true) can only be called on update thread.
MOZ_ASSERT_IF(aForUpdate, OnUpdateThread());
LookupCacheArray& lookupCaches =
aForUpdate ? mNewLookupCaches : mLookupCaches;
auto& rootStoreDirectory =
aForUpdate ? mUpdatingDirectory : mRootStoreDirectory;
for (auto c : lookupCaches) {
if (c->TableName().Equals(aTable)) {
return c;
}
}
// We don't want to create lookupcache when shutdown is already happening.
if (ShouldAbort()) {
return nullptr;
}
// thread method to convert table name to protocol version. Currently
// we can only know this by checking if the table name ends with
// '-proto'.
RefPtr<LookupCache> cache;
nsCString provider = GetProvider(aTable);
// Google requests SafeBrowsing related feature should only be enabled when
// the databases are update-to-date. Since we disable Safe Browsing update in
// Safe Mode, ignore tables provided by Google to ensure we don't show
// outdated warnings.
if (nsUrlClassifierUtils::IsInSafeMode()) {
if (provider.EqualsASCII("google") || provider.EqualsASCII("google4")) {
return nullptr;
}
}
if (StringEndsWith(aTable, "-proto"_ns)) {
cache = new LookupCacheV4(aTable, provider, rootStoreDirectory);
} else {
cache = new LookupCacheV2(aTable, provider, rootStoreDirectory);
}
nsresult rv = cache->Init();
if (NS_FAILED(rv)) {
return nullptr;
}
rv = cache->Open();
if (NS_SUCCEEDED(rv)) {
lookupCaches.AppendElement(cache);
return cache;
}
// At this point we failed to open LookupCache.
//
// GetLookupCache for update and for other usage will run on update thread
// their own realms potentially increases the concurrency.
if (aForUpdate) {
// Remove intermediaries no matter if it's due to file corruption or not.
RemoveUpdateIntermediaries();
return nullptr;
}
// Non-update case.
if (rv == NS_ERROR_FILE_CORRUPTED) {
// Remove all the on-disk data when the table's prefix file is corrupted.
LOG(("Failed to get prefixes from file for table %s, delete on-disk data!",
aTable.BeginReading()));
DeleteTables(mRootStoreDirectory, nsTArray<nsCString>{nsCString(aTable)});
}
return nullptr;
}
nsresult Classifier::ReadNoiseEntries(const Prefix& aPrefix,
const nsACString& aTableName,
uint32_t aCount,
PrefixArray& aNoiseEntries) {
RefPtr<LookupCache> cache = GetLookupCache(aTableName);
if (!cache) {
return NS_ERROR_FAILURE;
}
RefPtr<LookupCacheV2> cacheV2 = LookupCache::Cast<LookupCacheV2>(cache);
RefPtr<LookupCacheV4> cacheV4 = LookupCache::Cast<LookupCacheV4>(cache);
MOZ_ASSERT_IF(cacheV2, !cacheV4);
if (cache->PrefixLength() == 0) {
NS_WARNING("Could not find prefix in PrefixSet during noise lookup");
return NS_ERROR_FAILURE;
}
// We do not want to simply pick random prefixes, because this would allow
// averaging out the noise by analysing the traffic from Firefox users.
// Instead, we ensure the 'noise' is the same for the same prefix by seeding
// the random number generator with the prefix. We prefer not to use rand()
// which isn't thread safe, and the reseeding of which could trip up other
// parts othe code that expect actual random numbers.
// Here we use a simple LCG (Linear Congruential Generator) to generate
// random numbers. We seed the LCG with the prefix we are generating noise
// for.
uint32_t m = cache->PrefixLength();
uint32_t a = aCount % m;
uint32_t idx = aPrefix.ToUint32() % m;
for (size_t i = 0; i < aCount; i++) {
idx = (a * idx + a) % m;
uint32_t hash;
nsresult rv;
if (cacheV2) {
rv = cacheV2->GetPrefixByIndex(idx, &hash);
} else {
// We don't add noises for variable length prefix because of simplicity,
// so we will only get fixed length prefix (4 bytes).
rv = cacheV4->GetFixedLengthPrefixByIndex(idx, &hash);
}
if (NS_FAILED(rv)) {
NS_WARNING(
"Could not find the target prefix in PrefixSet during noise lookup");
return NS_ERROR_FAILURE;
}
Prefix newPrefix;
// In the case V4 little endian, we did swapping endian when converting from
// char* to int, should revert endian to make sure we will send hex string
if (!cacheV2 && !bool(MOZ_BIG_ENDIAN())) {
hash = NativeEndian::swapFromBigEndian(hash);
}
newPrefix.FromUint32(hash);
if (newPrefix != aPrefix) {
aNoiseEntries.AppendElement(newPrefix);
}
}
return NS_OK;
}
nsresult Classifier::LoadHashStore(nsIFile* aDirectory, nsACString& aResult,
nsTArray<nsCString>& aFailedTableNames) {
nsTArray<nsCString> tables;
nsTArray<nsCString> exts = {V2_METADATA_SUFFIX};
nsresult rv = ScanStoreDir(mRootStoreDirectory, exts, tables);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
for (const auto& table : tables) {
HashStore store(table, GetProvider(table), mRootStoreDirectory);
nsresult rv = store.Open();
if (NS_FAILED(rv) || !GetLookupCache(table)) {
// TableRequest is called right before applying an update.
// If we cannot retrieve metadata for a given table or we fail to
// load the prefixes for a table, reset the table to esnure we
// apply a full update to the table.
LOG(("Failed to get metadata for v2 table %s", table.get()));
aFailedTableNames.AppendElement(table);
continue;
}
ChunkSet& adds = store.AddChunks();
ChunkSet& subs = store.SubChunks();
// Open HashStore will always succeed even that is not a v2 table.
// So exception tables without add and sub chunks.
if (adds.Length() == 0 && subs.Length() == 0) {
continue;
}
aResult.Append(store.TableName());
aResult.Append(';');
if (adds.Length() > 0) {
aResult.AppendLiteral("a:");
nsAutoCString addList;
adds.Serialize(addList);
aResult.Append(addList);
}
if (subs.Length() > 0) {
if (adds.Length() > 0) {
aResult.Append(':');
}
aResult.AppendLiteral("s:");
nsAutoCString subList;
subs.Serialize(subList);
aResult.Append(subList);
}
aResult.Append('\n');
}
return rv;
}
nsresult Classifier::LoadMetadata(nsIFile* aDirectory, nsACString& aResult,
nsTArray<nsCString>& aFailedTableNames) {
nsTArray<nsCString> tables;
nsTArray<nsCString> exts = {V4_METADATA_SUFFIX};
nsresult rv = ScanStoreDir(mRootStoreDirectory, exts, tables);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
for (const auto& table : tables) {
RefPtr<LookupCache> c = GetLookupCache(table);
RefPtr<LookupCacheV4> lookupCacheV4 = LookupCache::Cast<LookupCacheV4>(c);
if (!lookupCacheV4) {
aFailedTableNames.AppendElement(table);
continue;
}
nsCString state, sha256;
rv = lookupCacheV4->LoadMetadata(state, sha256);
Telemetry::Accumulate(Telemetry::URLCLASSIFIER_VLPS_METADATA_CORRUPT,
rv == NS_ERROR_FILE_CORRUPTED);
if (NS_FAILED(rv)) {
LOG(("Failed to get metadata for v4 table %s", table.get()));
aFailedTableNames.AppendElement(table);
continue;
}
// The state might include '\n' so that we have to encode.
nsAutoCString stateBase64;
rv = Base64Encode(state, stateBase64);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
nsAutoCString checksumBase64;
rv = Base64Encode(sha256, checksumBase64);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
LOG(("Appending state '%s' and checksum '%s' for table %s",
stateBase64.get(), checksumBase64.get(), table.get()));
aResult.AppendPrintf("%s;%s:%s\n", table.get(), stateBase64.get(),
checksumBase64.get());
}
return rv;
}
bool Classifier::ShouldAbort() const {
return mIsClosed || nsUrlClassifierDBService::ShutdownHasStarted() ||
(mUpdateInterrupted && mUpdateThread->IsOnCurrentThread());
}
} // namespace safebrowsing
} // namespace mozilla