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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=8 et tw=80 : */
/* 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 "CachePushChecker.h"
#include "LoadContextInfo.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/net/SocketProcessChild.h"
#include "nsICacheEntry.h"
#include "nsICacheStorageService.h"
#include "nsICacheStorage.h"
#include "nsThreadUtils.h"
#include "CacheControlParser.h"
#include "nsHttpHandler.h"
namespace mozilla {
namespace net {
NS_IMPL_ISUPPORTS(CachePushChecker, nsICacheEntryOpenCallback);
CachePushChecker::CachePushChecker(nsIURI* aPushedURL,
const OriginAttributes& aOriginAttributes,
const nsACString& aRequestString,
std::function<void(bool)>&& aCallback)
: mPushedURL(aPushedURL),
mOriginAttributes(aOriginAttributes),
mRequestString(aRequestString),
mCallback(std::move(aCallback)),
mCurrentEventTarget(GetCurrentEventTarget()) {}
nsresult CachePushChecker::DoCheck() {
if (XRE_IsSocketProcess()) {
RefPtr<CachePushChecker> self = this;
return NS_DispatchToMainThread(
NS_NewRunnableFunction(
"CachePushChecker::DoCheck",
[self]() {
if (SocketProcessChild* child =
SocketProcessChild::GetSingleton()) {
child
->SendCachePushCheck(self->mPushedURL,
self->mOriginAttributes,
self->mRequestString)
->Then(
GetCurrentSerialEventTarget(), __func__,
[self](bool aResult) { self->InvokeCallback(aResult); },
[](const mozilla::ipc::ResponseRejectReason) {});
}
}),
NS_DISPATCH_NORMAL);
}
nsresult rv;
nsCOMPtr<nsICacheStorageService> css =
do_GetService("@mozilla.org/netwerk/cache-storage-service;1", &rv);
if (NS_FAILED(rv)) {
return rv;
}
RefPtr<LoadContextInfo> lci = GetLoadContextInfo(false, mOriginAttributes);
nsCOMPtr<nsICacheStorage> ds;
rv = css->DiskCacheStorage(lci, getter_AddRefs(ds));
if (NS_FAILED(rv)) {
return rv;
}
return ds->AsyncOpenURI(
mPushedURL, ""_ns,
nsICacheStorage::OPEN_READONLY | nsICacheStorage::OPEN_SECRETLY, this);
}
NS_IMETHODIMP
CachePushChecker::OnCacheEntryCheck(nsICacheEntry* entry, uint32_t* result) {
MOZ_ASSERT(XRE_IsParentProcess());
// We never care to fully open the entry, since we won't actually use it.
// We just want to be able to do all our checks to see if a future channel can
// use this entry, or if we need to accept the push.
*result = nsICacheEntryOpenCallback::ENTRY_NOT_WANTED;
bool isForcedValid = false;
entry->GetIsForcedValid(&isForcedValid);
nsHttpRequestHead requestHead;
requestHead.ParseHeaderSet(mRequestString.BeginReading());
nsHttpResponseHead cachedResponseHead;
bool acceptPush = true;
auto onExitGuard = MakeScopeExit([&] { InvokeCallback(acceptPush); });
nsresult rv =
nsHttp::GetHttpResponseHeadFromCacheEntry(entry, &cachedResponseHead);
if (NS_FAILED(rv)) {
// Couldn't make sense of what's in the cache entry, go ahead and accept
// the push.
return NS_OK;
}
if ((cachedResponseHead.Status() / 100) != 2) {
// Assume the push is sending us a success, while we don't have one in the
// cache, so we'll accept the push.
return NS_OK;
}
// Get the method that was used to generate the cached response
nsCString buf;
rv = entry->GetMetaDataElement("request-method", getter_Copies(buf));
if (NS_FAILED(rv)) {
// Can't check request method, accept the push
return NS_OK;
}
nsAutoCString pushedMethod;
requestHead.Method(pushedMethod);
if (!buf.Equals(pushedMethod)) {
// Methods don't match, accept the push
return NS_OK;
}
int64_t size, contentLength;
rv = nsHttp::CheckPartial(entry, &size, &contentLength, &cachedResponseHead);
if (NS_FAILED(rv)) {
// Couldn't figure out if this was partial or not, accept the push.
return NS_OK;
}
if (size == int64_t(-1) || contentLength != size) {
// This is partial content in the cache, accept the push.
return NS_OK;
}
nsAutoCString requestedETag;
if (NS_FAILED(requestHead.GetHeader(nsHttp::If_Match, requestedETag))) {
// Can't check etag
return NS_OK;
}
if (!requestedETag.IsEmpty()) {
nsAutoCString cachedETag;
if (NS_FAILED(cachedResponseHead.GetHeader(nsHttp::ETag, cachedETag))) {
// Can't check etag
return NS_OK;
}
if (!requestedETag.Equals(cachedETag)) {
// ETags don't match, accept the push.
return NS_OK;
}
}
nsAutoCString imsString;
Unused << requestHead.GetHeader(nsHttp::If_Modified_Since, imsString);
if (!buf.IsEmpty()) {
uint32_t ims = buf.ToInteger(&rv);
uint32_t lm;
rv = cachedResponseHead.GetLastModifiedValue(&lm);
if (NS_SUCCEEDED(rv) && lm && lm < ims) {
// The push appears to be newer than what's in our cache, accept it.
return NS_OK;
}
}
nsAutoCString cacheControlRequestHeader;
Unused << requestHead.GetHeader(nsHttp::Cache_Control,
cacheControlRequestHeader);
CacheControlParser cacheControlRequest(cacheControlRequestHeader);
if (cacheControlRequest.NoStore()) {
// Don't use a no-store cache entry, accept the push.
return NS_OK;
}
nsCString cachedAuth;
rv = entry->GetMetaDataElement("auth", getter_Copies(cachedAuth));
if (NS_SUCCEEDED(rv)) {
uint32_t lastModifiedTime;
rv = entry->GetLastModified(&lastModifiedTime);
if (NS_SUCCEEDED(rv)) {
if ((gHttpHandler->SessionStartTime() > lastModifiedTime) &&
!cachedAuth.IsEmpty()) {
// Need to revalidate this, as the auth is old. Accept the push.
return NS_OK;
}
if (cachedAuth.IsEmpty() &&
requestHead.HasHeader(nsHttp::Authorization)) {
// They're pushing us something with auth, but we didn't cache anything
// with auth. Accept the push.
return NS_OK;
}
}
}
bool weaklyFramed, isImmutable;
nsHttp::DetermineFramingAndImmutability(entry, &cachedResponseHead, true,
&weaklyFramed, &isImmutable);
// We'll need this value in later computations...
uint32_t lastModifiedTime;
rv = entry->GetLastModified(&lastModifiedTime);
if (NS_FAILED(rv)) {
// Ugh, this really sucks. OK, accept the push.
return NS_OK;
}
// Determine if this is the first time that this cache entry
// has been accessed during this session.
bool fromPreviousSession =
(gHttpHandler->SessionStartTime() > lastModifiedTime);
bool validationRequired = nsHttp::ValidationRequired(
isForcedValid, &cachedResponseHead, 0 /*NWGH: ??? - loadFlags*/, false,
false /* forceValidateCacheContent */, isImmutable, false, requestHead,
entry, cacheControlRequest, fromPreviousSession);
if (validationRequired) {
// A real channel would most likely hit the net at this point, so let's
// accept the push.
return NS_OK;
}
// If we get here, then we would be able to use this cache entry. Cancel the
// push so as not to waste any more bandwidth.
acceptPush = false;
return NS_OK;
}
NS_IMETHODIMP
CachePushChecker::OnCacheEntryAvailable(nsICacheEntry* entry, bool isNew,
nsresult result) {
// Nothing to do here, all the work is in OnCacheEntryCheck.
return NS_OK;
}
void CachePushChecker::InvokeCallback(bool aResult) {
RefPtr<CachePushChecker> self = this;
auto task = [self, aResult]() { self->mCallback(aResult); };
if (!mCurrentEventTarget->IsOnCurrentThread()) {
mCurrentEventTarget->Dispatch(
NS_NewRunnableFunction("CachePushChecker::InvokeCallback",
std::move(task)),
NS_DISPATCH_NORMAL);
return;
}
task();
}
} // namespace net
} // namespace mozilla
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