1 files changed, 162 insertions, 0 deletions
diff --git a/netwerk/base/nsDNSPrefetch.cpp b/netwerk/base/nsDNSPrefetch.cpp
new file mode 100644
index 0000000000..529171a347
--- /dev/null
+++ b/netwerk/base/nsDNSPrefetch.cpp
@@ -0,0 +1,162 @@
+/* -*- 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 "nsIDNSByTypeRecord.h"
+#include "nsICancelable.h"
+#include "nsIURI.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/Preferences.h"
+
+static nsIDNSService* sDNSService = nullptr;
+
+nsresult nsDNSPrefetch::Initialize(nsIDNSService* aDNSService) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  NS_IF_RELEASE(sDNSService);
+  sDNSService = aDNSService;
+  NS_IF_ADDREF(sDNSService);
+  return NS_OK;
+}
+
+nsresult nsDNSPrefetch::Shutdown() {
+  NS_IF_RELEASE(sDNSService);
+  return NS_OK;
+}
+
+nsDNSPrefetch::nsDNSPrefetch(nsIURI* aURI,
+                             mozilla::OriginAttributes& aOriginAttributes,
+                             nsIRequest::TRRMode aTRRMode,
+                             nsIDNSListener* aListener, bool storeTiming)
+    : mOriginAttributes(aOriginAttributes),
+      mStoreTiming(storeTiming),
+      mTRRMode(aTRRMode),
+      mListener(do_GetWeakReference(aListener)) {
+  aURI->GetAsciiHost(mHostname);
+}
+
+nsDNSPrefetch::nsDNSPrefetch(nsIURI* aURI,
+                             mozilla::OriginAttributes& aOriginAttributes,
+                             nsIRequest::TRRMode aTRRMode)
+    : mOriginAttributes(aOriginAttributes),
+      mStoreTiming(false),
+      mTRRMode(aTRRMode),
+      mListener(nullptr) {
+  aURI->GetAsciiHost(mHostname);
+}
+
+nsresult nsDNSPrefetch::Prefetch(uint32_t flags) {
+  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> target = mozilla::GetCurrentEventTarget();
+
+  flags |= nsIDNSService::GetFlagsFromTRRMode(mTRRMode);
+
+  return sDNSService->AsyncResolveNative(
+      mHostname, nsIDNSService::RESOLVE_TYPE_DEFAULT,
+      flags | nsIDNSService::RESOLVE_SPECULATE, nullptr, this, target,
+      mOriginAttributes, getter_AddRefs(tmpOutstanding));
+}
+
+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);
+}
+
+namespace {
+
+class HTTPSRRListener final : public nsIDNSListener {
+ public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIDNSLISTENER
+
+  explicit HTTPSRRListener(
+      std::function<void(nsIDNSHTTPSSVCRecord*)>&& aCallback)
+      : mResultCallback(std::move(aCallback)) {}
+
+ private:
+  ~HTTPSRRListener() = default;
+  std::function<void(nsIDNSHTTPSSVCRecord*)> mResultCallback;
+};
+
+NS_IMPL_ISUPPORTS(HTTPSRRListener, nsIDNSListener)
+
+NS_IMETHODIMP
+HTTPSRRListener::OnLookupComplete(nsICancelable* aRequest, nsIDNSRecord* aRec,
+                                  nsresult aStatus) {
+  if (NS_FAILED(aStatus)) {
+    mResultCallback(nullptr);
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsIDNSHTTPSSVCRecord> httpsRecord = do_QueryInterface(aRec);
+  mResultCallback(httpsRecord);
+  return NS_OK;
+}
+
+};  // namespace
+
+nsresult nsDNSPrefetch::FetchHTTPSSVC(
+    bool aRefreshDNS, bool aPrefetch,
+    std::function<void(nsIDNSHTTPSSVCRecord*)>&& aCallback) {
+  if (!sDNSService) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  nsCOMPtr<nsIEventTarget> target = mozilla::GetCurrentEventTarget();
+  uint32_t flags = nsIDNSService::GetFlagsFromTRRMode(mTRRMode);
+  if (aRefreshDNS) {
+    flags |= nsIDNSService::RESOLVE_BYPASS_CACHE;
+  }
+  if (aPrefetch) {
+    flags |= nsIDNSService::RESOLVE_SPECULATE;
+  }
+
+  nsCOMPtr<nsICancelable> tmpOutstanding;
+  nsCOMPtr<nsIDNSListener> listener = new HTTPSRRListener(std::move(aCallback));
+  return sDNSService->AsyncResolveNative(
+      mHostname, nsIDNSService::RESOLVE_TYPE_HTTPSSVC, flags, nullptr, listener,
+      target, mOriginAttributes, getter_AddRefs(tmpOutstanding));
+}
+
+NS_IMPL_ISUPPORTS(nsDNSPrefetch, nsIDNSListener)
+
+NS_IMETHODIMP
+nsDNSPrefetch::OnLookupComplete(nsICancelable* request, nsIDNSRecord* rec,
+                                nsresult status) {
+  if (mStoreTiming) {
+    mEndTimestamp = mozilla::TimeStamp::Now();
+  }
+  nsCOMPtr<nsIDNSListener> listener = do_QueryReferent(mListener);
+  if (listener) {
+    listener->OnLookupComplete(request, rec, status);
+  }
+
+  return NS_OK;
+}