Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1107 insertions, 0 deletions

diff --git a/toolkit/components/url-classifier/LookupCache.cpp b/toolkit/components/url-classifier/LookupCache.cpp
new file mode 100644
index 0000000000..3cb7b2f9eb
--- /dev/null
+++ b/toolkit/components/url-classifier/LookupCache.cpp
@@ -0,0 +1,1107 @@
+//* -*- 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 http://mozilla.org/MPL/2.0/. */
+
+#include "LookupCache.h"
+#include "LookupCacheV4.h"
+#include "HashStore.h"
+#include "nsIFileStreams.h"
+#include "nsISeekableStream.h"
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/Logging.h"
+#include "nsNetUtil.h"
+#include "nsCheckSummedOutputStream.h"
+#include "crc32c.h"
+#include "prprf.h"
+#include "Classifier.h"
+#include "nsUrlClassifierInfo.h"
+#include "nsUrlClassifierUtils.h"
+#include "nsUrlClassifierDBService.h"
+
+#ifdef DEBUG
+#  include "nsPrintfCString.h"
+#endif
+
+// We act as the main entry point for all the real lookups,
+// so note that those are not done to the actual HashStore.
+// The latter solely exists to store the data needed to handle
+// the updates from the protocol.
+
+// This module provides a front for PrefixSet, mUpdateCompletions,
+// and mGetHashCache, which together contain everything needed to
+// provide a classification as long as the data is up to date.
+
+// PrefixSet stores and provides lookups for 4-byte prefixes.
+// mUpdateCompletions contains 32-byte completions which were
+// contained in updates. They are retrieved from HashStore/.sbtore
+// on startup.
+// mGetHashCache contains 32-byte completions which were
+// returned from the gethash server. They are not serialized,
+// only cached until the next update.
+
+// 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)
+
+namespace mozilla {
+namespace safebrowsing {
+
+const uint32_t LookupCache::MAX_BUFFER_SIZE = 64 * 1024;
+
+const int CacheResultV2::VER = CacheResult::V2;
+const int CacheResultV4::VER = CacheResult::V4;
+
+const int LookupCacheV2::VER = 2;
+const uint32_t LookupCacheV2::VLPSET_MAGIC = 0xe5b862e7;
+const uint32_t LookupCacheV2::VLPSET_VERSION = 1;
+
+namespace {
+
+//////////////////////////////////////////////////////////////////////////
+// A set of lightweight functions for reading/writing value from/to file.
+template <typename T>
+struct ValueTraits {
+  static_assert(sizeof(T) <= LookupCacheV4::MAX_METADATA_VALUE_LENGTH,
+                "LookupCacheV4::MAX_METADATA_VALUE_LENGTH is too small.");
+  static uint32_t Length(const T& aValue) { return sizeof(T); }
+  static char* WritePtr(T& aValue, uint32_t aLength) { return (char*)&aValue; }
+  static const char* ReadPtr(const T& aValue) { return (char*)&aValue; }
+  static bool IsFixedLength() { return true; }
+};
+
+template <>
+struct ValueTraits<nsACString> {
+  static bool IsFixedLength() { return false; }
+
+  static uint32_t Length(const nsACString& aValue) { return aValue.Length(); }
+
+  static char* WritePtr(nsACString& aValue, uint32_t aLength) {
+    aValue.SetLength(aLength);
+    return aValue.BeginWriting();
+  }
+
+  static const char* ReadPtr(const nsACString& aValue) {
+    return aValue.BeginReading();
+  }
+};
+
+void CStringToHexString(const nsACString& aIn, nsACString& aOut) {
+  static const char* const lut = "0123456789ABCDEF";
+
+  size_t len = aIn.Length();
+  MOZ_ASSERT(len <= COMPLETE_SIZE);
+
+  aOut.SetCapacity(2 * len);
+  for (size_t i = 0; i < aIn.Length(); ++i) {
+    const char c = static_cast<char>(aIn[i]);
+    aOut.Append(lut[(c >> 4) & 0x0F]);
+    aOut.Append(lut[c & 15]);
+  }
+}
+
+#ifdef DEBUG
+nsCString GetFormattedTimeString(int64_t aCurTimeSec) {
+  PRExplodedTime pret;
+  PR_ExplodeTime(aCurTimeSec * PR_USEC_PER_SEC, PR_GMTParameters, &pret);
+
+  return nsPrintfCString("%04d-%02d-%02d %02d:%02d:%02d UTC", pret.tm_year,
+                         pret.tm_month + 1, pret.tm_mday, pret.tm_hour,
+                         pret.tm_min, pret.tm_sec);
+}
+#endif
+
+}  // end of unnamed namespace.
+////////////////////////////////////////////////////////////////////////
+
+template <typename T>
+nsresult LookupCache::WriteValue(nsIOutputStream* aOutputStream,
+                                 const T& aValue) {
+  uint32_t writeLength = ValueTraits<T>::Length(aValue);
+  MOZ_ASSERT(writeLength <= LookupCacheV4::MAX_METADATA_VALUE_LENGTH,
+             "LookupCacheV4::MAX_METADATA_VALUE_LENGTH is too small.");
+  if (!ValueTraits<T>::IsFixedLength()) {
+    // We need to write out the variable value length.
+    nsresult rv = WriteValue(aOutputStream, writeLength);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // Write out the value.
+  auto valueReadPtr = ValueTraits<T>::ReadPtr(aValue);
+  uint32_t written;
+  nsresult rv = aOutputStream->Write(valueReadPtr, writeLength, &written);
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (NS_WARN_IF(written != writeLength)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  return rv;
+}
+
+template <typename T>
+nsresult LookupCache::ReadValue(nsIInputStream* aInputStream, T& aValue) {
+  nsresult rv;
+
+  uint32_t readLength;
+  if (ValueTraits<T>::IsFixedLength()) {
+    readLength = ValueTraits<T>::Length(aValue);
+  } else {
+    // Read the variable value length from file.
+    nsresult rv = ReadValue(aInputStream, readLength);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // Sanity-check the readLength in case of disk corruption
+  // (see bug 1433636).
+  if (readLength > LookupCacheV4::MAX_METADATA_VALUE_LENGTH) {
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+
+  // Read the value.
+  uint32_t read;
+  auto valueWritePtr = ValueTraits<T>::WritePtr(aValue, readLength);
+  rv = aInputStream->Read(valueWritePtr, readLength, &read);
+  if (NS_FAILED(rv) || read != readLength) {
+    LOG(("Failed to read the value."));
+    return NS_FAILED(rv) ? rv : NS_ERROR_FAILURE;
+  }
+
+  return rv;
+}
+
+// These symbols are referenced from another compilation unit, but their
+// implementation depends on local symbols. Workaround this by forcing their
+// instantiation there.
+template nsresult mozilla::safebrowsing::LookupCache::WriteValue(
+    nsIOutputStream*, nsTSubstring<char> const&);
+template nsresult mozilla::safebrowsing::LookupCache::ReadValue(
+    nsIInputStream*, nsTSubstring<char>&);
+
+LookupCache::LookupCache(const nsACString& aTableName,
+                         const nsACString& aProvider,
+                         nsCOMPtr<nsIFile>& aRootStoreDir)
+    : mPrimed(false),
+      mTableName(aTableName),
+      mProvider(aProvider),
+      mRootStoreDirectory(aRootStoreDir),
+      mVLPrefixSet(nullptr) {
+  UpdateRootDirHandle(mRootStoreDirectory);
+}
+
+nsresult LookupCache::Open() {
+  LOG(("Loading PrefixSet for %s", mTableName.get()));
+  nsresult rv;
+  if (nsUrlClassifierUtils::IsMozTestTable(mTableName)) {
+    // For built-in test table, we don't load it from disk,
+    // test entries are directly added in memory.
+    rv = LoadMozEntries();
+  } else {
+    rv = LoadPrefixSet();
+  }
+
+  Unused << NS_WARN_IF(NS_FAILED(rv));
+
+  return rv;
+}
+
+nsresult LookupCache::Init() {
+  MOZ_ASSERT(!mVLPrefixSet);
+
+  mVLPrefixSet = new VariableLengthPrefixSet();
+  nsresult rv = mVLPrefixSet->Init(mTableName);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+nsresult LookupCache::UpdateRootDirHandle(
+    nsCOMPtr<nsIFile>& aNewRootStoreDirectory) {
+  nsresult rv;
+
+  if (aNewRootStoreDirectory != mRootStoreDirectory) {
+    rv = aNewRootStoreDirectory->Clone(getter_AddRefs(mRootStoreDirectory));
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  rv = Classifier::GetPrivateStoreDirectory(mRootStoreDirectory, mTableName,
+                                            mProvider,
+                                            getter_AddRefs(mStoreDirectory));
+
+  if (NS_FAILED(rv)) {
+    LOG(("Failed to get private store directory for %s", mTableName.get()));
+    mStoreDirectory = mRootStoreDirectory;
+  }
+
+  if (LOG_ENABLED()) {
+    nsString path;
+    mStoreDirectory->GetPath(path);
+    LOG(("Private store directory for %s is %s", mTableName.get(),
+         NS_ConvertUTF16toUTF8(path).get()));
+  }
+
+  return rv;
+}
+
+nsresult LookupCache::WriteFile() {
+  if (nsUrlClassifierDBService::ShutdownHasStarted()) {
+    return NS_ERROR_ABORT;
+  }
+
+  nsCOMPtr<nsIFile> psFile;
+  nsresult rv = mStoreDirectory->Clone(getter_AddRefs(psFile));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = psFile->AppendNative(mTableName + GetPrefixSetSuffix());
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = StoreToFile(psFile);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    LOG(("Failed to store the prefixset for table %s", mTableName.get()));
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+nsresult LookupCache::CheckCache(const Completion& aCompletion, bool* aHas,
+                                 bool* aConfirmed) {
+  // Shouldn't call this function if prefix is not in the database.
+  MOZ_ASSERT(*aHas);
+
+  *aConfirmed = false;
+
+  uint32_t prefix = aCompletion.ToUint32();
+
+  CachedFullHashResponse* fullHashResponse = mFullHashCache.Get(prefix);
+  if (!fullHashResponse) {
+    return NS_OK;
+  }
+
+  int64_t nowSec = PR_Now() / PR_USEC_PER_SEC;
+  int64_t expiryTimeSec;
+
+  FullHashExpiryCache& fullHashes = fullHashResponse->fullHashes;
+  nsDependentCSubstring completion(
+      reinterpret_cast<const char*>(aCompletion.buf), COMPLETE_SIZE);
+
+  // Check if we can find the fullhash in positive cache
+  if (fullHashes.Get(completion, &expiryTimeSec)) {
+    if (nowSec <= expiryTimeSec) {
+      // Url is NOT safe.
+      *aConfirmed = true;
+      LOG(("Found a valid fullhash in the positive cache"));
+    } else {
+      // Trigger a gethash request in this case(aConfirmed is false).
+      LOG(("Found an expired fullhash in the positive cache"));
+
+      // Remove fullhash entry from the cache when the negative cache
+      // is also expired because whether or not the fullhash is cached
+      // locally, we will need to consult the server next time we
+      // lookup this hash. We may as well remove it from our cache.
+      if (fullHashResponse->negativeCacheExpirySec < expiryTimeSec) {
+        fullHashes.Remove(completion);
+        if (fullHashes.Count() == 0 &&
+            fullHashResponse->negativeCacheExpirySec < nowSec) {
+          mFullHashCache.Remove(prefix);
+        }
+      }
+    }
+    return NS_OK;
+  }
+
+  // Check negative cache.
+  if (fullHashResponse->negativeCacheExpirySec >= nowSec) {
+    // Url is safe.
+    LOG(("Found a valid prefix in the negative cache"));
+    *aHas = false;
+  } else {
+    LOG(("Found an expired prefix in the negative cache"));
+    if (fullHashes.Count() == 0) {
+      mFullHashCache.Remove(prefix);
+    }
+  }
+
+  return NS_OK;
+}
+
+// This function remove cache entries whose negative cache time is expired.
+// It is possible that a cache entry whose positive cache time is not yet
+// expired but still being removed after calling this API. Right now we call
+// this on every update.
+void LookupCache::InvalidateExpiredCacheEntries() {
+  int64_t nowSec = PR_Now() / PR_USEC_PER_SEC;
+
+  for (auto iter = mFullHashCache.Iter(); !iter.Done(); iter.Next()) {
+    CachedFullHashResponse* response = iter.UserData();
+    if (response->negativeCacheExpirySec < nowSec) {
+      iter.Remove();
+    }
+  }
+}
+
+void LookupCache::CopyFullHashCache(const LookupCache* aSource) {
+  if (!aSource) {
+    return;
+  }
+
+  CopyClassHashTable<FullHashResponseMap>(aSource->mFullHashCache,
+                                          mFullHashCache);
+}
+
+void LookupCache::ClearCache() { mFullHashCache.Clear(); }
+
+void LookupCache::ClearAll() {
+  ClearCache();
+  ClearPrefixes();
+  mPrimed = false;
+}
+
+nsresult LookupCache::ClearPrefixes() {
+  // Clear by seting a empty map
+  PrefixStringMap map;
+  return mVLPrefixSet->SetPrefixes(map);
+}
+
+bool LookupCache::IsEmpty() const {
+  bool isEmpty;
+  mVLPrefixSet->IsEmpty(&isEmpty);
+  return isEmpty;
+}
+
+void LookupCache::GetCacheInfo(nsIUrlClassifierCacheInfo** aCache) const {
+  MOZ_ASSERT(aCache);
+
+  RefPtr<nsUrlClassifierCacheInfo> info = new nsUrlClassifierCacheInfo;
+  info->table = mTableName;
+
+  for (const auto& cacheEntry : mFullHashCache) {
+    RefPtr<nsUrlClassifierCacheEntry> entry = new nsUrlClassifierCacheEntry;
+
+    // Set prefix of the cache entry.
+    nsAutoCString prefix(reinterpret_cast<const char*>(&cacheEntry.GetKey()),
+                         PREFIX_SIZE);
+    CStringToHexString(prefix, entry->prefix);
+
+    // Set expiry of the cache entry.
+    CachedFullHashResponse* response = cacheEntry.GetWeak();
+    entry->expirySec = response->negativeCacheExpirySec;
+
+    // Set positive cache.
+    FullHashExpiryCache& fullHashes = response->fullHashes;
+    for (const auto& fullHashEntry : fullHashes) {
+      RefPtr<nsUrlClassifierPositiveCacheEntry> match =
+          new nsUrlClassifierPositiveCacheEntry;
+
+      // Set fullhash of positive cache entry.
+      CStringToHexString(fullHashEntry.GetKey(), match->fullhash);
+
+      // Set expiry of positive cache entry.
+      match->expirySec = fullHashEntry.GetData();
+
+      entry->matches.AppendElement(
+          static_cast<nsIUrlClassifierPositiveCacheEntry*>(match));
+    }
+
+    info->entries.AppendElement(
+        static_cast<nsIUrlClassifierCacheEntry*>(entry));
+  }
+
+  info.forget(aCache);
+}
+
+/* static */
+bool LookupCache::IsCanonicalizedIP(const nsACString& aHost) {
+  // The canonicalization process will have left IP addresses in dotted
+  // decimal with no surprises.
+  uint32_t i1, i2, i3, i4;
+  char c;
+  if (PR_sscanf(PromiseFlatCString(aHost).get(), "%u.%u.%u.%u%c", &i1, &i2, &i3,
+                &i4, &c) == 4) {
+    return (i1 <= 0xFF && i2 <= 0xFF && i3 <= 0xFF && i4 <= 0xFF);
+  }
+
+  return false;
+}
+
+// This is used when the URL is created by CreatePairwiseEntityListURI(),
+// which returns an URI like "toplevel.page/?resource=third.party.domain"
+// The fragment rule for the hostname(toplevel.page) is still the same
+// as Safe Browsing protocol.
+// The difference is that we always keep the path and query string and
+// generate an additional fragment by removing the leading component of
+// third.party.domain. This is to make sure we can find a match when a
+// exceptionlisted domain is eTLD.
+/* static */
+nsresult LookupCache::GetLookupEntitylistFragments(
+    const nsACString& aSpec, nsTArray<nsCString>* aFragments) {
+  aFragments->Clear();
+
+  nsACString::const_iterator begin, end, iter, iter_end;
+  aSpec.BeginReading(begin);
+  aSpec.EndReading(end);
+
+  iter = begin;
+  iter_end = end;
+
+  // Fallback to use default fragment rule when the URL doesn't contain
+  // "/?resoruce=" because this means the URL is not generated in
+  // CreatePairwiseEntityListURI()
+  if (!FindInReadable("/?resource="_ns, iter, iter_end)) {
+    return GetLookupFragments(aSpec, aFragments);
+  }
+
+  const nsACString& topLevelURL = Substring(begin, iter++);
+  const nsACString& thirdPartyURL = Substring(iter_end, end);
+
+  /**
+   * For the top-level URL, we follow the host fragment rule defined
+   * in the Safe Browsing protocol.
+   */
+  nsTArray<nsCString> topLevelURLs;
+  topLevelURLs.AppendElement(topLevelURL);
+
+  if (!IsCanonicalizedIP(topLevelURL)) {
+    topLevelURL.BeginReading(begin);
+    topLevelURL.EndReading(end);
+    int numTopLevelURLComponents = 0;
+    while (RFindInReadable("."_ns, begin, end) &&
+           numTopLevelURLComponents < MAX_HOST_COMPONENTS) {
+      // don't bother checking toplevel domains
+      if (++numTopLevelURLComponents >= 2) {
+        topLevelURL.EndReading(iter);
+        topLevelURLs.AppendElement(Substring(end, iter));
+      }
+      end = begin;
+      topLevelURL.BeginReading(begin);
+    }
+  }
+
+  /**
+   * The whiltelisted domain in the entity list may be eTLD or eTLD+1.
+   * Since the number of the domain name part in the third-party URL searching
+   * is always less than or equal to eTLD+1, we remove the leading
+   * component from the third-party domain to make sure we can find a match
+   * if the exceptionlisted domain stoed in the entity list is eTLD.
+   */
+  nsTArray<nsCString> thirdPartyURLs;
+  thirdPartyURLs.AppendElement(thirdPartyURL);
+
+  if (!IsCanonicalizedIP(thirdPartyURL)) {
+    thirdPartyURL.BeginReading(iter);
+    thirdPartyURL.EndReading(end);
+    if (FindCharInReadable('.', iter, end)) {
+      iter++;
+      nsAutoCString thirdPartyURLToAdd;
+      thirdPartyURLToAdd.Assign(Substring(iter++, end));
+
+      // don't bother checking toplevel domains
+      if (FindCharInReadable('.', iter, end)) {
+        thirdPartyURLs.AppendElement(thirdPartyURLToAdd);
+      }
+    }
+  }
+
+  for (size_t i = 0; i < topLevelURLs.Length(); i++) {
+    for (size_t j = 0; j < thirdPartyURLs.Length(); j++) {
+      nsAutoCString key;
+      key.Assign(topLevelURLs[i]);
+      key.Append("/?resource=");
+      key.Append(thirdPartyURLs[j]);
+
+      aFragments->AppendElement(key);
+    }
+  }
+
+  return NS_OK;
+}
+
+/* static */
+nsresult LookupCache::GetLookupFragments(const nsACString& aSpec,
+                                         nsTArray<nsCString>* aFragments)
+
+{
+  aFragments->Clear();
+
+  nsACString::const_iterator begin, end, iter;
+  aSpec.BeginReading(begin);
+  aSpec.EndReading(end);
+
+  iter = begin;
+  if (!FindCharInReadable('/', iter, end)) {
+    return NS_OK;
+  }
+
+  const nsACString& host = Substring(begin, iter++);
+  nsAutoCString path;
+  path.Assign(Substring(iter, end));
+
+  /**
+   * From the protocol doc:
+   * For the hostname, the client will try at most 5 different strings.  They
+   * are:
+   * a) The exact hostname of the url
+   * b) The 4 hostnames formed by starting with the last 5 components and
+   *    successivly removing the leading component.  The top-level component
+   *    can be skipped. This is not done if the hostname is a numerical IP.
+   */
+  nsTArray<nsCString> hosts;
+  hosts.AppendElement(host);
+
+  if (!IsCanonicalizedIP(host)) {
+    host.BeginReading(begin);
+    host.EndReading(end);
+    int numHostComponents = 0;
+    while (RFindInReadable("."_ns, begin, end) &&
+           numHostComponents < MAX_HOST_COMPONENTS) {
+      // don't bother checking toplevel domains
+      if (++numHostComponents >= 2) {
+        host.EndReading(iter);
+        hosts.AppendElement(Substring(end, iter));
+      }
+      end = begin;
+      host.BeginReading(begin);
+    }
+  }
+
+  /**
+   * From the protocol doc:
+   * For the path, the client will also try at most 6 different strings.
+   * They are:
+   * a) the exact path of the url, including query parameters
+   * b) the exact path of the url, without query parameters
+   * c) the 4 paths formed by starting at the root (/) and
+   *    successively appending path components, including a trailing
+   *    slash.  This behavior should only extend up to the next-to-last
+   *    path component, that is, a trailing slash should never be
+   *    appended that was not present in the original url.
+   */
+  nsTArray<nsCString> paths;
+  nsAutoCString pathToAdd;
+
+  path.BeginReading(begin);
+  path.EndReading(end);
+  iter = begin;
+  if (FindCharInReadable('?', iter, end)) {
+    pathToAdd = Substring(begin, iter);
+    paths.AppendElement(pathToAdd);
+    end = iter;
+  }
+
+  int numPathComponents = 1;
+  iter = begin;
+  while (FindCharInReadable('/', iter, end) &&
+         numPathComponents < MAX_PATH_COMPONENTS) {
+    iter++;
+    pathToAdd.Assign(Substring(begin, iter));
+    paths.AppendElement(pathToAdd);
+    numPathComponents++;
+  }
+
+  // If we haven't already done so, add the full path
+  if (!pathToAdd.Equals(path)) {
+    paths.AppendElement(path);
+  }
+  // Check an empty path (for whole-domain blocklist entries)
+  if (!paths.Contains(""_ns)) {
+    paths.AppendElement(""_ns);
+  }
+
+  for (uint32_t hostIndex = 0; hostIndex < hosts.Length(); hostIndex++) {
+    for (uint32_t pathIndex = 0; pathIndex < paths.Length(); pathIndex++) {
+      nsCString key;
+      key.Assign(hosts[hostIndex]);
+      key.Append('/');
+      key.Append(paths[pathIndex]);
+
+      aFragments->AppendElement(key);
+    }
+  }
+
+  return NS_OK;
+}
+
+nsresult LookupCache::LoadPrefixSet() {
+  nsCOMPtr<nsIFile> psFile;
+  nsresult rv = mStoreDirectory->Clone(getter_AddRefs(psFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = psFile->AppendNative(mTableName + GetPrefixSetSuffix());
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  bool exists;
+  rv = psFile->Exists(&exists);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (exists) {
+    LOG(("stored PrefixSet exists, loading from disk"));
+    rv = LoadFromFile(psFile);
+    if (NS_FAILED(rv)) {
+      return rv;
+    }
+    mPrimed = true;
+  } else {
+    // The only scenario we load the old .pset file is when we haven't received
+    // a SafeBrowsng update before. After receiving an update, new .vlpset will
+    // be stored while old .pset will be removed.
+    if (NS_SUCCEEDED(LoadLegacyFile())) {
+      mPrimed = true;
+    } else {
+      LOG(("no (usable) stored PrefixSet found"));
+    }
+  }
+
+#ifdef DEBUG
+  if (mPrimed) {
+    uint32_t size = SizeOfPrefixSet();
+    LOG(("SB tree done, size = %d bytes\n", size));
+  }
+#endif
+
+  return NS_OK;
+}
+
+size_t LookupCache::SizeOfPrefixSet() const {
+  return mVLPrefixSet->SizeOfIncludingThis(moz_malloc_size_of);
+}
+
+#if defined(DEBUG)
+void LookupCache::DumpCache() const {
+  if (!LOG_ENABLED()) {
+    return;
+  }
+
+  for (const auto& cacheEntry : mFullHashCache) {
+    CachedFullHashResponse* response = cacheEntry.GetWeak();
+
+    nsAutoCString prefix;
+    CStringToHexString(
+        nsCString(reinterpret_cast<const char*>(&cacheEntry.GetKey()),
+                  PREFIX_SIZE),
+        prefix);
+    LOG(("Cache prefix(%s): %s, Expiry: %s", mTableName.get(), prefix.get(),
+         GetFormattedTimeString(response->negativeCacheExpirySec).get()));
+
+    FullHashExpiryCache& fullHashes = response->fullHashes;
+    for (const auto& fullHashEntry : fullHashes) {
+      nsAutoCString fullhash;
+      CStringToHexString(fullHashEntry.GetKey(), fullhash);
+      LOG(("  - %s, Expiry: %s", fullhash.get(),
+           GetFormattedTimeString(fullHashEntry.GetData()).get()));
+    }
+  }
+}
+#endif
+
+nsresult LookupCache::StoreToFile(nsCOMPtr<nsIFile>& aFile) {
+  NS_ENSURE_ARG_POINTER(aFile);
+
+  uint32_t fileSize = sizeof(Header) +
+                      mVLPrefixSet->CalculatePreallocateSize() +
+                      nsCrc32CheckSumedOutputStream::CHECKSUM_SIZE;
+
+  nsCOMPtr<nsIOutputStream> localOutFile;
+  nsresult rv =
+      NS_NewSafeLocalFileOutputStream(getter_AddRefs(localOutFile), aFile,
+                                      PR_WRONLY | PR_TRUNCATE | PR_CREATE_FILE);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // Preallocate the file storage
+  {
+    nsCOMPtr<nsIFileOutputStream> fos(do_QueryInterface(localOutFile));
+    Telemetry::AutoTimer<Telemetry::URLCLASSIFIER_VLPS_FALLOCATE_TIME> timer;
+
+    Unused << fos->Preallocate(fileSize);
+  }
+
+  nsCOMPtr<nsIOutputStream> out;
+  rv = NS_NewCrc32OutputStream(getter_AddRefs(out), localOutFile.forget(),
+                               std::min(fileSize, MAX_BUFFER_SIZE));
+
+  // Write header
+  Header header;
+  GetHeader(header);
+
+  rv = WriteValue(out, header);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // Write prefixes
+  rv = mVLPrefixSet->WritePrefixes(out);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // Write checksum
+  nsCOMPtr<nsISafeOutputStream> safeOut = do_QueryInterface(out, &rv);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = safeOut->Finish();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  LOG(("[%s] Storing PrefixSet successful", mTableName.get()));
+
+  // This is to remove old ".pset" files if exist
+  Unused << ClearLegacyFile();
+  return NS_OK;
+}
+
+nsresult LookupCache::LoadFromFile(nsCOMPtr<nsIFile>& aFile) {
+  NS_ENSURE_ARG_POINTER(aFile);
+
+  Telemetry::AutoTimer<Telemetry::URLCLASSIFIER_VLPS_FILELOAD_TIME> timer;
+
+  nsCOMPtr<nsIInputStream> localInFile;
+  nsresult rv = NS_NewLocalFileInputStream(getter_AddRefs(localInFile), aFile,
+                                           PR_RDONLY | nsIFile::OS_READAHEAD);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // Calculate how big the file is, make sure our read buffer isn't bigger
+  // than the file itself which is just wasting memory.
+  int64_t fileSize;
+  rv = aFile->GetFileSize(&fileSize);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (fileSize < 0 || fileSize > UINT32_MAX) {
+    return NS_ERROR_FAILURE;
+  }
+
+  uint32_t bufferSize =
+      std::min<uint32_t>(static_cast<uint32_t>(fileSize), MAX_BUFFER_SIZE);
+
+  // Convert to buffered stream
+  nsCOMPtr<nsIInputStream> in;
+  rv = NS_NewBufferedInputStream(getter_AddRefs(in), localInFile.forget(),
+                                 bufferSize);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // Load header
+  Header header;
+  rv = ReadValue(in, header);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    LOG(("Failed to read header for %s", mTableName.get()));
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+
+  rv = SanityCheck(header);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // Load data
+  rv = mVLPrefixSet->LoadPrefixes(in);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  // Load crc32 checksum and verify
+  rv = VerifyCRC32(in);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  mPrimed = true;
+
+  LOG(("[%s] Loading PrefixSet successful", mTableName.get()));
+  return NS_OK;
+}
+
+// This function assumes CRC32 checksum is in the end of the input stream
+nsresult LookupCache::VerifyCRC32(nsCOMPtr<nsIInputStream>& aIn) {
+  nsCOMPtr<nsISeekableStream> seekIn = do_QueryInterface(aIn);
+  nsresult rv = seekIn->Seek(nsISeekableStream::NS_SEEK_SET, 0);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  uint64_t len;
+  rv = aIn->Available(&len);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  uint32_t calculateCrc32 = ~0;
+
+  // We don't want to include the checksum itself
+  len = len - nsCrc32CheckSumedOutputStream::CHECKSUM_SIZE;
+
+  static const uint64_t STREAM_BUFFER_SIZE = 4096;
+  char buffer[STREAM_BUFFER_SIZE];
+  while (len) {
+    uint32_t read;
+    uint64_t readLimit = std::min<uint64_t>(STREAM_BUFFER_SIZE, len);
+
+    rv = aIn->Read(buffer, readLimit, &read);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    calculateCrc32 = ComputeCrc32c(
+        calculateCrc32, reinterpret_cast<const uint8_t*>(buffer), read);
+
+    len -= read;
+  }
+
+  // Now read the CRC32
+  uint32_t crc32;
+  ReadValue(aIn, crc32);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (crc32 != calculateCrc32) {
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+
+  return NS_OK;
+}
+
+nsresult LookupCacheV2::Has(const Completion& aCompletion, bool* aHas,
+                            uint32_t* aMatchLength, bool* aConfirmed) {
+  *aHas = *aConfirmed = false;
+  *aMatchLength = 0;
+
+  uint32_t length = 0;
+  nsDependentCSubstring fullhash;
+  fullhash.Rebind((const char*)aCompletion.buf, COMPLETE_SIZE);
+
+  uint32_t prefix = aCompletion.ToUint32();
+
+  nsresult rv = mVLPrefixSet->Matches(prefix, fullhash, &length);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (length == 0) {
+    return NS_OK;
+  }
+
+  MOZ_ASSERT(length == PREFIX_SIZE || length == COMPLETE_SIZE);
+
+  *aHas = true;
+  *aMatchLength = length;
+  *aConfirmed = length == COMPLETE_SIZE;
+
+  if (!(*aConfirmed)) {
+    rv = CheckCache(aCompletion, aHas, aConfirmed);
+  }
+
+  return rv;
+}
+
+nsresult LookupCacheV2::Build(AddPrefixArray& aAddPrefixes,
+                              AddCompleteArray& aAddCompletes) {
+  nsresult rv = mVLPrefixSet->SetPrefixes(aAddPrefixes, aAddCompletes);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+  mPrimed = true;
+
+  return NS_OK;
+}
+
+nsresult LookupCacheV2::GetPrefixes(FallibleTArray<uint32_t>& aAddPrefixes) {
+  if (!mPrimed) {
+    // This can happen if its a new table, so no error.
+    LOG(("GetPrefixes from empty LookupCache"));
+    return NS_OK;
+  }
+
+  return mVLPrefixSet->GetFixedLengthPrefixes(&aAddPrefixes, nullptr);
+}
+
+nsresult LookupCacheV2::GetPrefixes(FallibleTArray<uint32_t>& aAddPrefixes,
+                                    FallibleTArray<nsCString>& aAddCompletes) {
+  if (!mPrimed) {
+    // This can happen if its a new table, so no error.
+    LOG(("GetHashes from empty LookupCache"));
+    return NS_OK;
+  }
+
+  return mVLPrefixSet->GetFixedLengthPrefixes(&aAddPrefixes, &aAddCompletes);
+}
+
+nsresult LookupCacheV2::GetPrefixByIndex(uint32_t aIndex,
+                                         uint32_t* aOutPrefix) const {
+  NS_ENSURE_ARG_POINTER(aOutPrefix);
+
+  return mVLPrefixSet->GetFixedLengthPrefixByIndex(aIndex, aOutPrefix);
+}
+
+void LookupCacheV2::AddGethashResultToCache(
+    const AddCompleteArray& aAddCompletes, const MissPrefixArray& aMissPrefixes,
+    int64_t aExpirySec) {
+  static const int64_t CACHE_DURATION_SEC = 15 * 60;
+  int64_t defaultExpirySec = PR_Now() / PR_USEC_PER_SEC + CACHE_DURATION_SEC;
+  if (aExpirySec != 0) {
+    defaultExpirySec = aExpirySec;
+  }
+
+  for (const AddComplete& add : aAddCompletes) {
+    nsDependentCSubstring fullhash(
+        reinterpret_cast<const char*>(add.CompleteHash().buf), COMPLETE_SIZE);
+
+    CachedFullHashResponse* response =
+        mFullHashCache.GetOrInsertNew(add.ToUint32());
+    response->negativeCacheExpirySec = defaultExpirySec;
+
+    FullHashExpiryCache& fullHashes = response->fullHashes;
+    fullHashes.InsertOrUpdate(fullhash, defaultExpirySec);
+  }
+
+  for (const Prefix& prefix : aMissPrefixes) {
+    CachedFullHashResponse* response =
+        mFullHashCache.GetOrInsertNew(prefix.ToUint32());
+
+    response->negativeCacheExpirySec = defaultExpirySec;
+  }
+}
+
+void LookupCacheV2::GetHeader(Header& aHeader) {
+  aHeader.magic = LookupCacheV2::VLPSET_MAGIC;
+  aHeader.version = LookupCacheV2::VLPSET_VERSION;
+}
+
+nsresult LookupCacheV2::SanityCheck(const Header& aHeader) {
+  if (aHeader.magic != LookupCacheV2::VLPSET_MAGIC) {
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+
+  if (aHeader.version != LookupCacheV2::VLPSET_VERSION) {
+    return NS_ERROR_FAILURE;
+  }
+
+  return NS_OK;
+}
+
+nsresult LookupCacheV2::LoadLegacyFile() {
+  // Because mozilla Safe Browsing v2 server only includes completions
+  // in the update, we can simplify this function by only loading .sbtore
+  if (!mProvider.EqualsLiteral("mozilla")) {
+    return NS_OK;
+  }
+
+  HashStore store(mTableName, mProvider, mRootStoreDirectory);
+
+  // Support loading version 3 HashStore.
+  nsresult rv = store.Open(3);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (store.AddChunks().Length() == 0 && store.SubChunks().Length() == 0) {
+    // Return when file doesn't exist
+    return NS_OK;
+  }
+
+  AddPrefixArray prefix;
+  AddCompleteArray addComplete;
+
+  rv = store.ReadCompletionsLegacyV3(addComplete);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return Build(prefix, addComplete);
+}
+
+nsresult LookupCacheV2::ClearLegacyFile() {
+  nsCOMPtr<nsIFile> file;
+  nsresult rv = mStoreDirectory->Clone(getter_AddRefs(file));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = file->AppendNative(mTableName + ".pset"_ns);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  bool exists;
+  rv = file->Exists(&exists);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (exists) {
+    rv = file->Remove(false);
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    LOG(("[%s]Old PrefixSet is successfully removed!", mTableName.get()));
+  }
+
+  return NS_OK;
+}
+
+nsCString LookupCacheV2::GetPrefixSetSuffix() const { return ".vlpset"_ns; }
+
+// Support creating built-in entries for phsihing, malware, unwanted, harmful,
+// tracking/tracking exceptionlist and flash block tables.
+//
+nsresult LookupCacheV2::LoadMozEntries() {
+  // We already have the entries, return
+  if (!IsEmpty() || IsPrimed()) {
+    return NS_OK;
+  }
+
+  nsTArray<nsLiteralCString> entries;
+
+  if (mTableName.EqualsLiteral("moztest-phish-simple")) {
+    // Entries for phishing table
+    entries.AppendElement("itisatrap.org/firefox/its-a-trap.html"_ns);
+  } else if (mTableName.EqualsLiteral("moztest-malware-simple")) {
+    // Entries for malware table
+    entries.AppendElement("itisatrap.org/firefox/its-an-attack.html"_ns);
+  } else if (mTableName.EqualsLiteral("moztest-unwanted-simple")) {
+    // Entries for unwanted table
+    entries.AppendElement("itisatrap.org/firefox/unwanted.html"_ns);
+  } else if (mTableName.EqualsLiteral("moztest-harmful-simple")) {
+    // Entries for harmfule tables
+    entries.AppendElement("itisatrap.org/firefox/harmful.html"_ns);
+  } else if (mTableName.EqualsLiteral("moztest-track-simple")) {
+    // Entries for tracking table
+    entries.AppendElement("trackertest.org/"_ns);
+    entries.AppendElement("itisatracker.org/"_ns);
+  } else if (mTableName.EqualsLiteral("moztest-trackwhite-simple")) {
+    // Entries for tracking entitylist table
+    entries.AppendElement("itisatrap.org/?resource=itisatracker.org"_ns);
+  } else if (mTableName.EqualsLiteral("moztest-block-simple")) {
+    // Entries for flash block table
+    entries.AppendElement("itisatrap.org/firefox/blocked.html"_ns);
+  } else {
+    MOZ_ASSERT_UNREACHABLE();
+  }
+
+  AddPrefixArray prefix;
+  AddCompleteArray completes;
+  for (const auto& entry : entries) {
+    AddComplete add;
+    if (NS_FAILED(add.complete.FromPlaintext(entry))) {
+      continue;
+    }
+    if (!completes.AppendElement(add, fallible)) {
+      return NS_ERROR_OUT_OF_MEMORY;
+    }
+  }
+
+  return Build(prefix, completes);
+}
+
+}  // namespace safebrowsing
+}  // namespace mozilla