1 files changed, 356 insertions, 0 deletions
diff --git a/toolkit/components/url-classifier/LookupCache.h b/toolkit/components/url-classifier/LookupCache.h
new file mode 100644
index 0000000000..090f8eb733
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+++ b/toolkit/components/url-classifier/LookupCache.h
@@ -0,0 +1,356 @@
+//* -*- 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/. */
+
+#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 {
+
+#define MAX_HOST_COMPONENTS 5
+#define MAX_PATH_COMPONENTS 4
+
+class LookupResult {
+ public:
+  LookupResult()
+      : mNoise(false),
+        mProtocolConfirmed(false),
+        mPartialHashLength(0),
+        mConfirmed(false),
+        mProtocolV2(true) {}
+
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(LookupResult);
+
+  // The fragment that matched in the LookupCache
+  union {
+    Prefix fixedLengthPrefix;
+    Completion complete;
+  } hash;
+
+  const Completion& CompleteHash() const {
+    MOZ_ASSERT(!mNoise);
+    return hash.complete;
+  }
+
+  nsCString PartialHash() const {
+    MOZ_ASSERT(mPartialHashLength <= COMPLETE_SIZE);
+    if (mNoise) {
+      return nsCString(
+          reinterpret_cast<const char*>(hash.fixedLengthPrefix.buf),
+          PREFIX_SIZE);
+    } else {
+      return nsCString(reinterpret_cast<const char*>(hash.complete.buf),
+                       mPartialHashLength);
+    }
+  }
+
+  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;
+
+ private:
+  ~LookupResult() = default;
+};
+
+typedef nsTArray<RefPtr<LookupResult>> LookupResultArray;
+
+class CacheResult {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(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;
+
+ protected:
+  virtual ~CacheResult() = default;
+};
+
+class CacheResultV2 final : public CacheResult {
+ public:
+  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 {
+ public:
+  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 {
+ public:
+  // Check for a canonicalized IP address.
+  static bool IsCanonicalizedIP(const nsACString& aHost);
+
+  // take a lookup string (www.hostname.com/path/to/resource.html) 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);
+
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(LookupCache);
+
+  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();
+  }
+
+#if DEBUG
+  void DumpCache() const;
+#endif
+
+  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);
+  }
+
+ private:
+  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;
+
+ protected:
+  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;
+
+  template <typename T>
+  static nsresult WriteValue(nsIOutputStream* aOutputStream, const T& aValue);
+  template <typename T>
+  static nsresult ReadValue(nsIInputStream* aInputStream, T& aValue);
+};
+
+typedef nsTArray<RefPtr<LookupCache>> LookupCacheArray;
+
+class LookupCacheV2 final : public LookupCache {
+ public:
+  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;
+
+ protected:
+  virtual nsCString GetPrefixSetSuffix() const override;
+
+ private:
+  ~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
+
+#endif