gecko-dev/netwerk/base/nsDNSPrefetch.cpp

131 строка
4.3 KiB
C++

/* -*- Mode: C++; tab-width: 4; 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 "nsDNSPrefetch.h"
#include "nsCOMPtr.h"
#include "nsString.h"
#include "nsThreadUtils.h"
#include "nsIDNSListener.h"
#include "nsIDNSService.h"
#include "nsICancelable.h"
#include "nsIURI.h"
#include "mozilla/Preferences.h"
static nsIDNSService* sDNSService = nullptr;
static bool sESNIEnabled = false;
nsresult nsDNSPrefetch::Initialize(nsIDNSService* aDNSService) {
NS_IF_RELEASE(sDNSService);
sDNSService = aDNSService;
NS_IF_ADDREF(sDNSService);
mozilla::Preferences::AddBoolVarCache(&sESNIEnabled,
"network.security.esni.enabled");
return NS_OK;
}
nsresult nsDNSPrefetch::Shutdown() {
NS_IF_RELEASE(sDNSService);
return NS_OK;
}
nsDNSPrefetch::nsDNSPrefetch(nsIURI* aURI,
mozilla::OriginAttributes& aOriginAttributes,
nsIDNSListener* aListener, bool storeTiming)
: mOriginAttributes(aOriginAttributes),
mStoreTiming(storeTiming),
mListener(do_GetWeakReference(aListener)) {
aURI->GetAsciiHost(mHostname);
mIsHttps = false;
aURI->SchemeIs("https", &mIsHttps);
}
nsresult nsDNSPrefetch::Prefetch(uint16_t flags) {
// This can work properly only if this call is on the main thread.
// Curenlty we use nsDNSPrefetch only in nsHttpChannel which will call
// PrefetchHigh() from the main thread. Let's add assertion to catch
// if things change.
MOZ_ASSERT(NS_IsMainThread(), "Expecting DNS callback on main thread.");
if (mHostname.IsEmpty()) return NS_ERROR_NOT_AVAILABLE;
if (!sDNSService) return NS_ERROR_NOT_AVAILABLE;
nsCOMPtr<nsICancelable> tmpOutstanding;
if (mStoreTiming) mStartTimestamp = mozilla::TimeStamp::Now();
// If AsyncResolve fails, for example because prefetching is disabled,
// then our timing will be useless. However, in such a case,
// mEndTimestamp will be a null timestamp and callers should check
// TimingsValid() before using the timing.
nsCOMPtr<nsIEventTarget> main = mozilla::GetMainThreadEventTarget();
nsresult rv = sDNSService->AsyncResolveNative(
mHostname, flags | nsIDNSService::RESOLVE_SPECULATE, this, main,
mOriginAttributes, getter_AddRefs(tmpOutstanding));
if (NS_FAILED(rv)) {
return rv;
}
// Fetch esni keys if needed.
if (sESNIEnabled && mIsHttps) {
nsAutoCString esniHost;
esniHost.Append("_esni.");
esniHost.Append(mHostname);
sDNSService->AsyncResolveByTypeNative(
esniHost, nsIDNSService::RESOLVE_TYPE_TXT,
flags | nsIDNSService::RESOLVE_SPECULATE, this, main, mOriginAttributes,
getter_AddRefs(tmpOutstanding));
}
return NS_OK;
}
nsresult nsDNSPrefetch::PrefetchLow(bool refreshDNS) {
return Prefetch(nsIDNSService::RESOLVE_PRIORITY_LOW |
(refreshDNS ? nsIDNSService::RESOLVE_BYPASS_CACHE : 0));
}
nsresult nsDNSPrefetch::PrefetchMedium(bool refreshDNS) {
return Prefetch(nsIDNSService::RESOLVE_PRIORITY_MEDIUM |
(refreshDNS ? nsIDNSService::RESOLVE_BYPASS_CACHE : 0));
}
nsresult nsDNSPrefetch::PrefetchHigh(bool refreshDNS) {
return Prefetch(refreshDNS ? nsIDNSService::RESOLVE_BYPASS_CACHE : 0);
}
NS_IMPL_ISUPPORTS(nsDNSPrefetch, nsIDNSListener)
NS_IMETHODIMP
nsDNSPrefetch::OnLookupComplete(nsICancelable* request, nsIDNSRecord* rec,
nsresult status) {
MOZ_ASSERT(NS_IsMainThread(), "Expecting DNS callback on main thread.");
if (mStoreTiming) {
mEndTimestamp = mozilla::TimeStamp::Now();
}
nsCOMPtr<nsIDNSListener> listener = do_QueryReferent(mListener);
if (listener) {
listener->OnLookupComplete(request, rec, status);
}
return NS_OK;
}
NS_IMETHODIMP
nsDNSPrefetch::OnLookupByTypeComplete(nsICancelable* request,
nsIDNSByTypeRecord* res,
nsresult status) {
MOZ_ASSERT(NS_IsMainThread(), "Expecting DNS callback on main thread.");
if (mStoreTiming) {
mEndTimestamp = mozilla::TimeStamp::Now();
}
nsCOMPtr<nsIDNSListener> listener = do_QueryReferent(mListener);
if (listener) {
listener->OnLookupByTypeComplete(request, res, status);
}
return NS_OK;
}