gecko-dev/image/ImageCacheKey.cpp

170 lines
5.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; 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 "ImageCacheKey.h"
#include "mozilla/HashFunctions.h"
#include "mozilla/Move.h"
#include "nsContentUtils.h"
#include "nsICookieService.h"
#include "nsLayoutUtils.h"
#include "nsString.h"
#include "mozilla/AntiTrackingCommon.h"
#include "mozilla/dom/BlobURLProtocolHandler.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/ServiceWorkerManager.h"
#include "nsIDocument.h"
#include "nsPrintfCString.h"
namespace mozilla {
using namespace dom;
namespace image {
static Maybe<uint64_t>
BlobSerial(nsIURI* aURI)
{
nsAutoCString spec;
aURI->GetSpec(spec);
RefPtr<BlobImpl> blob;
if (NS_SUCCEEDED(NS_GetBlobForBlobURISpec(spec, getter_AddRefs(blob))) &&
blob) {
return Some(blob->GetSerialNumber());
}
return Nothing();
}
ImageCacheKey::ImageCacheKey(nsIURI* aURI,
const OriginAttributes& aAttrs,
nsIDocument* aDocument,
nsresult& aRv)
: mURI(aURI)
, mOriginAttributes(aAttrs)
, mControlledDocument(GetSpecialCaseDocumentToken(aDocument, aURI))
, mHash(0)
, mIsChrome(false)
{
if (SchemeIs("blob")) {
mBlobSerial = BlobSerial(mURI);
} else if (SchemeIs("chrome")) {
mIsChrome = true;
}
// Since we frequently call Hash() several times in a row on the same
// ImageCacheKey, as an optimization we compute our hash once and store it.
nsPrintfCString ptr("%p", mControlledDocument);
nsAutoCString suffix;
mOriginAttributes.CreateSuffix(suffix);
if (mBlobSerial) {
aRv = mURI->GetRef(mBlobRef);
NS_ENSURE_SUCCESS_VOID(aRv);
mHash = HashGeneric(*mBlobSerial, HashString(mBlobRef));
} else {
nsAutoCString spec;
aRv = mURI->GetSpec(spec);
NS_ENSURE_SUCCESS_VOID(aRv);
mHash = HashString(spec);
}
mHash = AddToHash(mHash, HashString(suffix), HashString(ptr));
}
ImageCacheKey::ImageCacheKey(const ImageCacheKey& aOther)
: mURI(aOther.mURI)
, mBlobSerial(aOther.mBlobSerial)
, mBlobRef(aOther.mBlobRef)
, mOriginAttributes(aOther.mOriginAttributes)
, mControlledDocument(aOther.mControlledDocument)
, mHash(aOther.mHash)
, mIsChrome(aOther.mIsChrome)
{ }
ImageCacheKey::ImageCacheKey(ImageCacheKey&& aOther)
: mURI(std::move(aOther.mURI))
, mBlobSerial(std::move(aOther.mBlobSerial))
, mBlobRef(std::move(aOther.mBlobRef))
, mOriginAttributes(aOther.mOriginAttributes)
, mControlledDocument(aOther.mControlledDocument)
, mHash(aOther.mHash)
, mIsChrome(aOther.mIsChrome)
{ }
bool
ImageCacheKey::operator==(const ImageCacheKey& aOther) const
{
// Don't share the image cache between a controlled document and anything else.
if (mControlledDocument != aOther.mControlledDocument) {
return false;
}
// The origin attributes always have to match.
if (mOriginAttributes != aOther.mOriginAttributes) {
return false;
}
if (mBlobSerial || aOther.mBlobSerial) {
// If at least one of us has a blob serial, just compare the blob serial and
// the ref portion of the URIs.
return mBlobSerial == aOther.mBlobSerial &&
mBlobRef == aOther.mBlobRef;
}
// For non-blob URIs, compare the URIs.
bool equals = false;
nsresult rv = mURI->Equals(aOther.mURI, &equals);
return NS_SUCCEEDED(rv) && equals;
}
bool
ImageCacheKey::SchemeIs(const char* aScheme)
{
bool matches = false;
return NS_SUCCEEDED(mURI->SchemeIs(aScheme, &matches)) && matches;
}
/* static */ void*
ImageCacheKey::GetSpecialCaseDocumentToken(nsIDocument* aDocument, nsIURI* aURI)
{
// Cookie-averse documents can never have storage granted to them. Since they
// may not have inner windows, they would require special handling below, so
// just bail out early here.
if (!aDocument || aDocument->IsCookieAverse()) {
return nullptr;
}
// For controlled documents, we cast the pointer into a void* to avoid
// dereferencing it (since we only use it for comparisons).
RefPtr<ServiceWorkerManager> swm = ServiceWorkerManager::GetInstance();
if (swm && aDocument->GetController().isSome()) {
return aDocument;
}
// If the window is 3rd party resource, let's see if first-party storage
// access is granted for this image.
if (nsContentUtils::IsTrackingResourceWindow(aDocument->GetInnerWindow())) {
return nsContentUtils::StorageDisabledByAntiTracking(aDocument, aURI) ?
aDocument : nullptr;
}
// Another scenario is if this image is a 3rd party resource loaded by a
// first party context. In this case, we should check if the nsIChannel has
// been marked as tracking resource, but we don't have the channel yet at
// this point. The best approach here is to be conservative: if we are sure
// that the permission is granted, let's return a nullptr. Otherwise, let's
// make a unique image cache.
if (!AntiTrackingCommon::MaybeIsFirstPartyStorageAccessGrantedFor(aDocument->GetInnerWindow(),
aURI)) {
return aDocument;
}
return nullptr;
}
} // namespace image
} // namespace mozilla