image/ImageCacheKey.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /**
   7  * ImageCacheKey is the key type for the image cache (see imgLoader.h).
   8  */
   9
  10 #ifndef mozilla_image_src_ImageCacheKey_h
  11 #define mozilla_image_src_ImageCacheKey_h
  12
  13 #include "mozilla/BasePrincipal.h"
  14 #include "mozilla/Maybe.h"
  15 #include "mozilla/RefPtr.h"
  16 #include "PLDHashTable.h"
  17 #include "nsIDocShell.h"
  18
  19 class nsIURI;
  20
  21 namespace mozilla {
  22
  23 enum CORSMode : uint8_t;
  24
  25 namespace image {
  26
  27 /**
  28  * An ImageLib cache entry key.
  29  *
  30  * We key the cache on the initial URI (before any redirects), with some
  31  * canonicalization applied. See ComputeHash() for the details.
  32  * Controlled documents do not share their cache entries with
  33  * non-controlled documents, or other controlled documents.
  34  */
  35 class ImageCacheKey final {
  36  public:
  37   ImageCacheKey(nsIURI*, CORSMode, const OriginAttributes&, dom::Document*);
  38
  39   ImageCacheKey(const ImageCacheKey& aOther);
  40   ImageCacheKey(ImageCacheKey&& aOther);
  41
  42   bool operator==(const ImageCacheKey& aOther) const;
  43   PLDHashNumber Hash() const {
  44     if (MOZ_UNLIKELY(mHash.isNothing())) {
  45       EnsureHash();
  46     }
  47     return mHash.value();
  48   }
  49
  50   /// A weak pointer to the URI.
  51   nsIURI* URI() const { return mURI; }
  52
  53   CORSMode GetCORSMode() const { return mCORSMode; }
  54
  55   const OriginAttributes& OriginAttributesRef() const {
  56     return mOriginAttributes;
  57   }
  58
  59   const nsCString& IsolationKeyRef() const { return mIsolationKey; }
  60
  61   /// A token indicating which service worker controlled document this entry
  62   /// belongs to, if any.
  63   void* ControlledDocument() const { return mControlledDocument; }
  64
  65  private:
  66   // For ServiceWorker we need to use the document as
  67   // token for the key. All those exceptions are handled by this method.
  68   static void* GetSpecialCaseDocumentToken(dom::Document* aDocument);
  69
  70   // For anti-tracking we need to use an isolation key. It can be the suffix of
  71   // the PatitionedPrincipal (see StoragePrincipalHelper.h) or the top-level
  72   // document's base domain. This is handled by this method.
  73   static nsCString GetIsolationKey(dom::Document* aDocument, nsIURI* aURI);
  74
  75   // The AppType of the docshell an image is loaded in can influence whether the
  76   // image is allowed to load. The specific AppType is fetched by this method.
  77   static nsIDocShell::AppType GetAppType(dom::Document* aDocument);
  78
  79   void EnsureHash() const;
  80
  81   nsCOMPtr<nsIURI> mURI;
  82   const OriginAttributes mOriginAttributes;
  83   void* mControlledDocument;
  84   nsCString mIsolationKey;
  85   mutable Maybe<PLDHashNumber> mHash;
  86   const CORSMode mCORSMode;
  87   const nsIDocShell::AppType mAppType;
  88 };
  89
  90 }  // namespace image
  91 }  // namespace mozilla
  92
  93 #endif  // mozilla_image_src_ImageCacheKey_h