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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
* file, You can obtain one at */
#ifndef LookupCache_h__
#define LookupCache_h__
#include "Entries.h"
#include "nsString.h"
#include "nsTArray.h"
#include "nsCOMPtr.h"
#include "nsIFile.h"
#include "mozilla/RefPtr.h"
#include "nsUrlClassifierPrefixSet.h"
#include "VariableLengthPrefixSet.h"
#include "mozilla/Logging.h"
#include "mozilla/TypedEnumBits.h"
#include "nsIUrlClassifierInfo.h"
namespace mozilla {
namespace safebrowsing {
class LookupResult {
: mNoise(false),
mProtocolV2(true) {}
// The fragment that matched in the LookupCache
union {
Prefix fixedLengthPrefix;
Completion complete;
} hash;
const Completion& CompleteHash() const {
return hash.complete;
nsCString PartialHash() const {
MOZ_ASSERT(mPartialHashLength <= COMPLETE_SIZE);
if (mNoise) {
return nsCString(
reinterpret_cast<const char*>(hash.fixedLengthPrefix.buf),
} else {
return nsCString(reinterpret_cast<const char*>(hash.complete.buf),
nsAutoCString PartialHashHex() const {
nsAutoCString hex;
for (size_t i = 0; i < mPartialHashLength; i++) {
hex.AppendPrintf("%.2X", hash.complete.buf[i]);
return hex;
bool Confirmed() const { return mConfirmed || mProtocolConfirmed; }
// True if we have a complete match for this hash in the table.
bool Complete() const { return mPartialHashLength == COMPLETE_SIZE; }
// True if this is a noise entry, i.e. an extra entry
// that is inserted to mask the true URL we are requesting.
// Noise entries will not have a complete 256-bit hash as
// they are fetched from the local 32-bit database and we
// don't know the corresponding full URL.
bool mNoise;
bool mProtocolConfirmed;
nsCString mTableName;
uint32_t mPartialHashLength;
// True as long as this lookup is complete and hasn't expired.
bool mConfirmed;
bool mProtocolV2;
~LookupResult() = default;
typedef nsTArray<RefPtr<LookupResult>> LookupResultArray;
class CacheResult {
enum { V2, V4 };
virtual int Ver() const = 0;
virtual bool findCompletion(const Completion& aCompletion) const = 0;
template <typename T>
static const T* Cast(const CacheResult* aThat) {
return ((aThat && T::VER == aThat->Ver())
? reinterpret_cast<const T*>(aThat)
: nullptr);
nsCString table;
Prefix prefix;
virtual ~CacheResult() = default;
class CacheResultV2 final : public CacheResult {
static const int VER;
// True when 'prefix' in CacheResult indicates a prefix that
// cannot be completed.
bool miss = false;
// 'completion' and 'addChunk' are used when 'miss' field is false.
Completion completion;
uint32_t addChunk;
bool operator==(const CacheResultV2& aOther) const {
if (table != aOther.table || prefix != aOther.prefix ||
miss != aOther.miss) {
return false;
if (miss) {
return true;
return completion == aOther.completion && addChunk == aOther.addChunk;
bool findCompletion(const Completion& aCompletion) const override {
return completion == aCompletion;
virtual int Ver() const override { return VER; }
class CacheResultV4 final : public CacheResult {
static const int VER;
CachedFullHashResponse response;
bool operator==(const CacheResultV4& aOther) const {
return table == aOther.table && prefix == aOther.prefix &&
response == aOther.response;
bool findCompletion(const Completion& aCompletion) const override {
nsDependentCSubstring completion(
reinterpret_cast<const char*>(aCompletion.buf), COMPLETE_SIZE);
return response.fullHashes.Contains(completion);
virtual int Ver() const override { return VER; }
typedef nsTArray<RefPtr<const CacheResult>> ConstCacheResultArray;
class LookupCache {
// Check for a canonicalized IP address.
static bool IsCanonicalizedIP(const nsACString& aHost);
// take a lookup string ( and
// expand it into the set of fragments that should be searched for in an
// entry
static nsresult GetLookupFragments(const nsACString& aSpec,
nsTArray<nsCString>* aFragments);
static nsresult GetLookupEntitylistFragments(const nsACString& aSpec,
nsTArray<nsCString>* aFragments);
LookupCache(const nsACString& aTableName, const nsACString& aProvider,
nsCOMPtr<nsIFile>& aStoreFile);
const nsCString& TableName() const { return mTableName; }
// The directory handle where we operate will
// be moved away when a backup is made.
nsresult UpdateRootDirHandle(nsCOMPtr<nsIFile>& aRootStoreDirectory);
// Write data stored in lookup cache to disk.
nsresult WriteFile();
bool IsPrimed() const { return mPrimed; };
// Called when update to clear expired entries.
void InvalidateExpiredCacheEntries();
// Copy fullhash cache from another LookupCache.
void CopyFullHashCache(const LookupCache* aSource);
// Clear fullhash cache from fullhash/gethash response.
void ClearCache();
// Check if completions can be found in cache.
// Currently this is only used by testcase.
bool IsInCache(uint32_t key) const { return mFullHashCache.Get(key); };
uint32_t PrefixLength() const {
return mVLPrefixSet->FixedLengthPrefixLength();
void DumpCache() const;
void GetCacheInfo(nsIUrlClassifierCacheInfo** aCache) const;
nsresult VerifyCRC32(nsCOMPtr<nsIInputStream>& aIn);
virtual nsresult Open();
virtual nsresult Init();
virtual nsresult ClearPrefixes();
virtual nsresult Has(const Completion& aCompletion, bool* aHas,
uint32_t* aMatchLength, bool* aConfirmed) = 0;
// Prefix files file header
struct Header {
uint32_t magic;
uint32_t version;
virtual nsresult StoreToFile(nsCOMPtr<nsIFile>& aFile);
virtual nsresult LoadFromFile(nsCOMPtr<nsIFile>& aFile);
virtual bool IsEmpty() const;
virtual void ClearAll();
virtual nsresult LoadMozEntries() = 0;
template <typename T>
static T* Cast(LookupCache* aThat) {
return ((aThat && T::VER == aThat->Ver()) ? reinterpret_cast<T*>(aThat)
: nullptr);
template <typename T>
static const T* Cast(const LookupCache* aThat) {
return ((aThat && T::VER == aThat->Ver())
? reinterpret_cast<const T*>(aThat)
: nullptr);
nsresult LoadPrefixSet();
virtual size_t SizeOfPrefixSet() const;
virtual nsCString GetPrefixSetSuffix() const = 0;
virtual int Ver() const = 0;
virtual void GetHeader(Header& aHeader) = 0;
virtual nsresult SanityCheck(const Header& aHeader) = 0;
virtual nsresult LoadLegacyFile() = 0;
virtual nsresult ClearLegacyFile() = 0;
virtual ~LookupCache() = default;
// Buffer size for file read/write
static const uint32_t MAX_BUFFER_SIZE;
// Check completions in positive cache and prefix in negative cache.
// 'aHas' and 'aConfirmed' are output parameters.
nsresult CheckCache(const Completion& aCompletion, bool* aHas,
bool* aConfirmed);
bool mPrimed; // true when the PrefixSet has been loaded (or constructed)
const nsCString mTableName;
const nsCString mProvider;
nsCOMPtr<nsIFile> mRootStoreDirectory;
nsCOMPtr<nsIFile> mStoreDirectory;
// For gtest to inspect private members.
friend class PerProviderDirectoryTestUtils;
// Cache stores fullhash response(V4)/gethash response(V2)
FullHashResponseMap mFullHashCache;
RefPtr<VariableLengthPrefixSet> mVLPrefixSet;
typedef nsTArray<RefPtr<LookupCache>> LookupCacheArray;
class LookupCacheV2 final : public LookupCache {
explicit LookupCacheV2(const nsACString& aTableName,
const nsACString& aProvider,
nsCOMPtr<nsIFile>& aStoreFile)
: LookupCache(aTableName, aProvider, aStoreFile) {}
virtual nsresult Has(const Completion& aCompletion, bool* aHas,
uint32_t* aMatchLength, bool* aConfirmed) override;
nsresult Build(AddPrefixArray& aAddPrefixes, AddCompleteArray& aAddCompletes);
nsresult GetPrefixes(FallibleTArray<uint32_t>& aAddPrefixes);
nsresult GetPrefixes(FallibleTArray<uint32_t>& aAddPrefixes,
FallibleTArray<nsCString>& aAddCompletes);
nsresult GetPrefixByIndex(uint32_t aIndex, uint32_t* aOutPrefix) const;
// This will Clear() the passed arrays when done.
// 'aExpirySec' is used by testcase to config an expired time.
void AddGethashResultToCache(const AddCompleteArray& aAddCompletes,
const MissPrefixArray& aMissPrefixes,
int64_t aExpirySec = 0);
virtual nsresult LoadMozEntries() override;
static const int VER;
static const uint32_t VLPSET_MAGIC;
static const uint32_t VLPSET_VERSION;
virtual nsCString GetPrefixSetSuffix() const override;
~LookupCacheV2() = default;
virtual int Ver() const override { return VER; }
virtual void GetHeader(Header& aHeader) override;
virtual nsresult SanityCheck(const Header& aHeader) override;
virtual nsresult LoadLegacyFile() override;
virtual nsresult ClearLegacyFile() override;
} // namespace safebrowsing
} // namespace mozilla