The Tor Browser: netwerk/dns/ChildDNSService.cpp@ca08bd8f51b2 (annotated)

netwerk/dns/ChildDNSService.cpp@ca08bd8f51b2 (annotated)

netwerk/dns/ChildDNSService.cpp

Wed, 31 Dec 2014 06:55:46 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:55:46 +0100
changeset 1: ca08bd8f51b2
permissions: -rw-r--r--

Added tag TORBROWSER_REPLICA for changeset 6474c204b198

 /* 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 "mozilla/net/ChildDNSService.h"
 #include "nsIDNSListener.h"
 #include "nsNetUtil.h"
 #include "nsIThread.h"
 #include "nsThreadUtils.h"
 #include "nsIXPConnect.h"
 #include "nsIPrefService.h"
 #include "nsIProtocolProxyService.h"
 #include "mozilla/net/NeckoChild.h"
 #include "mozilla/net/DNSRequestChild.h"
 #include "mozilla/net/DNSListenerProxy.h"
 namespace mozilla {
 namespace net {
 //-----------------------------------------------------------------------------
 // ChildDNSService
 //-----------------------------------------------------------------------------
 static ChildDNSService *gChildDNSService;
 static const char kPrefNameDisablePrefetch[] = "network.dns.disablePrefetch";
 ChildDNSService* ChildDNSService::GetSingleton()
 {
   MOZ_ASSERT(IsNeckoChild());
   if (!gChildDNSService) {
     gChildDNSService = new ChildDNSService();
   }
   NS_ADDREF(gChildDNSService);
   return gChildDNSService;
 }
 NS_IMPL_ISUPPORTS(ChildDNSService,
                   nsIDNSService,
                   nsPIDNSService,
                   nsIObserver)
 ChildDNSService::ChildDNSService()
   : mFirstTime(true)
   , mOffline(false)
 {
   MOZ_ASSERT(IsNeckoChild());
 }
 ChildDNSService::~ChildDNSService()
 {
 }
 //-----------------------------------------------------------------------------
 // ChildDNSService::nsIDNSService
 //-----------------------------------------------------------------------------
 NS_IMETHODIMP
 ChildDNSService::AsyncResolve(const nsACString  &hostname,
                               uint32_t           flags,
                               nsIDNSListener    *listener,
                               nsIEventTarget    *target_,
                               nsICancelable    **result)
 {
   NS_ENSURE_TRUE(gNeckoChild != nullptr, NS_ERROR_FAILURE);
   if (mDisablePrefetch && (flags & RESOLVE_SPECULATE)) {
     return NS_ERROR_DNS_LOOKUP_QUEUE_FULL;
   }
   // Support apps being 'offline' even if parent is not: avoids DNS traffic by
   // apps that have been told they are offline.
   if (mOffline) {
     flags |= RESOLVE_OFFLINE;
   }
   // make sure JS callers get notification on the main thread
   nsCOMPtr<nsIEventTarget> target = target_;
   nsCOMPtr<nsIXPConnectWrappedJS> wrappedListener = do_QueryInterface(listener);
   if (wrappedListener && !target) {
     nsCOMPtr<nsIThread> mainThread;
     NS_GetMainThread(getter_AddRefs(mainThread));
     target = do_QueryInterface(mainThread);
   }
   if (target) {
     // Guarantee listener freed on main thread.  Not sure we need this in child
     // (or in parent in nsDNSService.cpp) but doesn't hurt.
     listener = new DNSListenerProxy(listener, target);
   }
   nsRefPtr<DNSRequestChild> childReq =
     new DNSRequestChild(nsCString(hostname), flags, listener, target);
   childReq->StartRequest();
   childReq.forget(result);
   return NS_OK;
 }
 NS_IMETHODIMP
 ChildDNSService::CancelAsyncResolve(const nsACString  &aHostname,
                                     uint32_t           aFlags,
                                     nsIDNSListener    *aListener,
                                     nsresult           aReason)
 {
   if (mDisablePrefetch && (aFlags & RESOLVE_SPECULATE)) {
     return NS_ERROR_DNS_LOOKUP_QUEUE_FULL;
   }
   // TODO: keep a hashtable of pending requests, so we can obey cancel semantics
   // (call OnLookupComplete with aReason).  Also possible we could send IPDL to
   // parent to cancel.
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP
 ChildDNSService::Resolve(const nsACString &hostname,
                          uint32_t          flags,
                          nsIDNSRecord    **result)
 {
   // not planning to ever support this, since sync IPDL is evil.
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP
 ChildDNSService::GetDNSCacheEntries(nsTArray<mozilla::net::DNSCacheEntries> *args)
 {
   // Only used by networking dashboard, so may not ever need this in child.
   // (and would provide a way to spy on what hosts other apps are connecting to,
   // unless we start keeping per-app DNS caches).
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP
 ChildDNSService::GetMyHostName(nsACString &result)
 {
   // TODO: get value from parent during PNecko construction?
   return NS_ERROR_NOT_AVAILABLE;
 }
 //-----------------------------------------------------------------------------
 // ChildDNSService::nsPIDNSService
 //-----------------------------------------------------------------------------
 nsresult
 ChildDNSService::Init()
 {
   // Disable prefetching either by explicit preference or if a manual proxy
   // is configured
   bool disablePrefetch = false;
   int  proxyType = nsIProtocolProxyService::PROXYCONFIG_DIRECT;
   nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
   prefs->GetBoolPref(kPrefNameDisablePrefetch, &disablePrefetch);
   if (prefs) {
     prefs->GetIntPref("network.proxy.type", &proxyType);
     prefs->GetBoolPref(kPrefNameDisablePrefetch, &disablePrefetch);
   }
   if (mFirstTime) {
     mFirstTime = false;
     if (prefs) {
       prefs->AddObserver(kPrefNameDisablePrefetch, this, false);
       // Monitor these to see if there is a change in proxy configuration
       // If a manual proxy is in use, disable prefetch implicitly
       prefs->AddObserver("network.proxy.type", this, false);
     }
   }
   mDisablePrefetch = disablePrefetch ||
                      (proxyType == nsIProtocolProxyService::PROXYCONFIG_MANUAL);
   return NS_OK;
 }
 nsresult
 ChildDNSService::Shutdown()
 {
   return NS_OK;
 }
 NS_IMETHODIMP
 ChildDNSService::GetPrefetchEnabled(bool *outVal)
 {
   *outVal = !mDisablePrefetch;
   return NS_OK;
 }
 NS_IMETHODIMP
 ChildDNSService::SetPrefetchEnabled(bool inVal)
 {
   mDisablePrefetch = !inVal;
   return NS_OK;
 }
 NS_IMETHODIMP
 ChildDNSService::GetOffline(bool* aResult)
 {
   *aResult = mOffline;
   return NS_OK;
 }
 NS_IMETHODIMP
 ChildDNSService::SetOffline(bool value)
 {
   mOffline = value;
   return NS_OK;
 }
 //-----------------------------------------------------------------------------
 // ChildDNSService::nsIObserver
 //-----------------------------------------------------------------------------
 NS_IMETHODIMP
 ChildDNSService::Observe(nsISupports *subject, const char *topic,
                          const char16_t *data)
 {
   // we are only getting called if a preference has changed.
   NS_ASSERTION(strcmp(topic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID) == 0,
                "unexpected observe call");
   // Reread prefs
   Init();
   return NS_OK;
 }
 } // namespace net
 } // namespace mozilla

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netwerk/dns/ChildDNSService.cpp@ca08bd8f51b2 (annotated)

netwerk/dns/ChildDNSService.cpp