The Tor Browser: netwerk/base/src/nsServerSocket.cpp@b8a032363ba2 (annotated)

netwerk/base/src/nsServerSocket.cpp@b8a032363ba2 (annotated)

netwerk/base/src/nsServerSocket.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* vim:set ts=2 sw=2 et cindent: */
 /* 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 "nsSocketTransport2.h"
 #include "nsServerSocket.h"
 #include "nsProxyRelease.h"
 #include "nsAutoPtr.h"
 #include "nsError.h"
 #include "nsNetCID.h"
 #include "prnetdb.h"
 #include "prio.h"
 #include "nsThreadUtils.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/Endian.h"
 #include "mozilla/net/DNS.h"
 #include "nsServiceManagerUtils.h"
 #include "nsIFile.h"
 using namespace mozilla;
 using namespace mozilla::net;
 static NS_DEFINE_CID(kSocketTransportServiceCID, NS_SOCKETTRANSPORTSERVICE_CID);
 //-----------------------------------------------------------------------------
 typedef void (nsServerSocket:: *nsServerSocketFunc)(void);
 static nsresult
 PostEvent(nsServerSocket *s, nsServerSocketFunc func)
 {
   nsCOMPtr<nsIRunnable> ev = NS_NewRunnableMethod(s, func);
   if (!ev)
     return NS_ERROR_OUT_OF_MEMORY;
   if (!gSocketTransportService)
     return NS_ERROR_FAILURE;
   return gSocketTransportService->Dispatch(ev, NS_DISPATCH_NORMAL);
 }
 //-----------------------------------------------------------------------------
 // nsServerSocket
 //-----------------------------------------------------------------------------
 nsServerSocket::nsServerSocket()
   : mLock("nsServerSocket.mLock")
   , mFD(nullptr)
   , mAttached(false)
   , mKeepWhenOffline(false)
 {
   // we want to be able to access the STS directly, and it may not have been
   // constructed yet.  the STS constructor sets gSocketTransportService.
   if (!gSocketTransportService)
   {
     // This call can fail if we're offline, for example.
     nsCOMPtr<nsISocketTransportService> sts =
         do_GetService(kSocketTransportServiceCID);
   }
   // make sure the STS sticks around as long as we do
   NS_IF_ADDREF(gSocketTransportService);
 }
 nsServerSocket::~nsServerSocket()
 {
   Close(); // just in case :)
   // release our reference to the STS
   nsSocketTransportService *serv = gSocketTransportService;
   NS_IF_RELEASE(serv);
 }
 void
 nsServerSocket::OnMsgClose()
 {
   SOCKET_LOG(("nsServerSocket::OnMsgClose [this=%p]\n", this));
   if (NS_FAILED(mCondition))
     return;
   // tear down socket.  this signals the STS to detach our socket handler.
   mCondition = NS_BINDING_ABORTED;
   // if we are attached, then we'll close the socket in our OnSocketDetached.
   // otherwise, call OnSocketDetached from here.
   if (!mAttached)
     OnSocketDetached(mFD);
 }
 void
 nsServerSocket::OnMsgAttach()
 {
   SOCKET_LOG(("nsServerSocket::OnMsgAttach [this=%p]\n", this));
   if (NS_FAILED(mCondition))
     return;
   mCondition = TryAttach();
   // if we hit an error while trying to attach then bail...
   if (NS_FAILED(mCondition))
   {
     NS_ASSERTION(!mAttached, "should not be attached already");
     OnSocketDetached(mFD);
   }
 }
 nsresult
 nsServerSocket::TryAttach()
 {
   nsresult rv;
   if (!gSocketTransportService)
     return NS_ERROR_FAILURE;
   //
   // find out if it is going to be ok to attach another socket to the STS.
   // if not then we have to wait for the STS to tell us that it is ok.
   // the notification is asynchronous, which means that when we could be
   // in a race to call AttachSocket once notified.  for this reason, when
   // we get notified, we just re-enter this function.  as a result, we are
   // sure to ask again before calling AttachSocket.  in this way we deal
   // with the race condition.  though it isn't the most elegant solution,
   // it is far simpler than trying to build a system that would guarantee
   // FIFO ordering (which wouldn't even be that valuable IMO).  see bug
   // 194402 for more info.
   //
   if (!gSocketTransportService->CanAttachSocket())
   {
     nsCOMPtr<nsIRunnable> event =
       NS_NewRunnableMethod(this, &nsServerSocket::OnMsgAttach);
     if (!event)
       return NS_ERROR_OUT_OF_MEMORY;
     nsresult rv = gSocketTransportService->NotifyWhenCanAttachSocket(event);
     if (NS_FAILED(rv))
       return rv;
   }
   //
   // ok, we can now attach our socket to the STS for polling
   //
   rv = gSocketTransportService->AttachSocket(mFD, this);
   if (NS_FAILED(rv))
     return rv;
   mAttached = true;
   //
   // now, configure our poll flags for listening...
   //
   mPollFlags = (PR_POLL_READ | PR_POLL_EXCEPT);
   return NS_OK;
 }
 //-----------------------------------------------------------------------------
 // nsServerSocket::nsASocketHandler
 //-----------------------------------------------------------------------------
 void
 nsServerSocket::OnSocketReady(PRFileDesc *fd, int16_t outFlags)
 {
   NS_ASSERTION(NS_SUCCEEDED(mCondition), "oops");
   NS_ASSERTION(mFD == fd, "wrong file descriptor");
   NS_ASSERTION(outFlags != -1, "unexpected timeout condition reached");
   if (outFlags & (PR_POLL_ERR | PR_POLL_HUP | PR_POLL_NVAL))
   {
     NS_WARNING("error polling on listening socket");
     mCondition = NS_ERROR_UNEXPECTED;
     return;
   }
   PRFileDesc *clientFD;
   PRNetAddr prClientAddr;
   NetAddr clientAddr;
   // NSPR doesn't tell us the peer address's length (as provided by the
   // 'accept' system call), so we can't distinguish between named,
   // unnamed, and abstract peer addresses. Clear prClientAddr first, so
   // that the path will at least be reliably empty for unnamed and
   // abstract addresses, and not garbage when the peer is unnamed.
   memset(&prClientAddr, 0, sizeof(prClientAddr));
   clientFD = PR_Accept(mFD, &prClientAddr, PR_INTERVAL_NO_WAIT);
   PRNetAddrToNetAddr(&prClientAddr, &clientAddr);
   if (!clientFD)
   {
     NS_WARNING("PR_Accept failed");
     mCondition = NS_ERROR_UNEXPECTED;
   }
   else
   {
     nsRefPtr<nsSocketTransport> trans = new nsSocketTransport;
     if (!trans)
       mCondition = NS_ERROR_OUT_OF_MEMORY;
     else
     {
       nsresult rv = trans->InitWithConnectedSocket(clientFD, &clientAddr);
       if (NS_FAILED(rv))
         mCondition = rv;
       else
         mListener->OnSocketAccepted(this, trans);
     }
   }
 }
 void
 nsServerSocket::OnSocketDetached(PRFileDesc *fd)
 {
   // force a failure condition if none set; maybe the STS is shutting down :-/
   if (NS_SUCCEEDED(mCondition))
     mCondition = NS_ERROR_ABORT;
   if (mFD)
   {
     NS_ASSERTION(mFD == fd, "wrong file descriptor");
     PR_Close(mFD);
     mFD = nullptr;
   }
   if (mListener)
   {
     mListener->OnStopListening(this, mCondition);
     // need to atomically clear mListener.  see our Close() method.
     nsIServerSocketListener *listener = nullptr;
     {
       MutexAutoLock lock(mLock);
       mListener.swap(listener);
     }
     // XXX we need to proxy the release to the listener's target thread to work
     // around bug 337492.
     if (listener)
       NS_ProxyRelease(mListenerTarget, listener);
   }
 }
 void
 nsServerSocket::IsLocal(bool *aIsLocal)
 {
 #if defined(XP_UNIX)
   // Unix-domain sockets are always local.
   if (mAddr.raw.family == PR_AF_LOCAL)
   {
     *aIsLocal = true;
     return;
   }
 #endif
   // If bound to loopback, this server socket only accepts local connections.
   *aIsLocal = PR_IsNetAddrType(&mAddr, PR_IpAddrLoopback);
 }
 void
 nsServerSocket::KeepWhenOffline(bool *aKeepWhenOffline)
 {
   *aKeepWhenOffline = mKeepWhenOffline;
 }
 //-----------------------------------------------------------------------------
 // nsServerSocket::nsISupports
 //-----------------------------------------------------------------------------
 NS_IMPL_ISUPPORTS(nsServerSocket, nsIServerSocket)
 //-----------------------------------------------------------------------------
 // nsServerSocket::nsIServerSocket
 //-----------------------------------------------------------------------------
 NS_IMETHODIMP
 nsServerSocket::Init(int32_t aPort, bool aLoopbackOnly, int32_t aBackLog)
 {
   return InitSpecialConnection(aPort, aLoopbackOnly ? LoopbackOnly : 0, aBackLog);
 }
 NS_IMETHODIMP
 nsServerSocket::InitWithFilename(nsIFile *aPath, uint32_t aPermissions, int32_t aBacklog)
 {
 #if defined(XP_UNIX)
   nsresult rv;
   nsAutoCString path;
   rv = aPath->GetNativePath(path);
   if (NS_FAILED(rv))
     return rv;
   // Create a Unix domain PRNetAddr referring to the given path.
   PRNetAddr addr;
   if (path.Length() > sizeof(addr.local.path) - 1)
     return NS_ERROR_FILE_NAME_TOO_LONG;
   addr.local.family = PR_AF_LOCAL;
   memcpy(addr.local.path, path.get(), path.Length());
   addr.local.path[path.Length()] = '\0';
   rv = InitWithAddress(&addr, aBacklog);
   if (NS_FAILED(rv))
     return rv;
   return aPath->SetPermissions(aPermissions);
 #else
   return NS_ERROR_SOCKET_ADDRESS_NOT_SUPPORTED;
 #endif
 }
 NS_IMETHODIMP
 nsServerSocket::InitSpecialConnection(int32_t aPort, nsServerSocketFlag aFlags,
                                       int32_t aBackLog)
 {
   PRNetAddrValue val;
   PRNetAddr addr;
   if (aPort < 0)
     aPort = 0;
   if (aFlags & nsIServerSocket::LoopbackOnly)
     val = PR_IpAddrLoopback;
   else
     val = PR_IpAddrAny;
   PR_SetNetAddr(val, PR_AF_INET, aPort, &addr);
   mKeepWhenOffline = ((aFlags & nsIServerSocket::KeepWhenOffline) != 0);
   return InitWithAddress(&addr, aBackLog);
 }
 NS_IMETHODIMP
 nsServerSocket::InitWithAddress(const PRNetAddr *aAddr, int32_t aBackLog)
 {
   NS_ENSURE_TRUE(mFD == nullptr, NS_ERROR_ALREADY_INITIALIZED);
   //
   // configure listening socket...
   //
   mFD = PR_OpenTCPSocket(aAddr->raw.family);
   if (!mFD)
   {
     NS_WARNING("unable to create server socket");
     return ErrorAccordingToNSPR(PR_GetError());
   }
   PRSocketOptionData opt;
   opt.option = PR_SockOpt_Reuseaddr;
   opt.value.reuse_addr = true;
   PR_SetSocketOption(mFD, &opt);
   opt.option = PR_SockOpt_Nonblocking;
   opt.value.non_blocking = true;
   PR_SetSocketOption(mFD, &opt);
   if (PR_Bind(mFD, aAddr) != PR_SUCCESS)
   {
     NS_WARNING("failed to bind socket");
     goto fail;
   }
   if (aBackLog < 0)
     aBackLog = 5; // seems like a reasonable default
   if (PR_Listen(mFD, aBackLog) != PR_SUCCESS)
   {
     NS_WARNING("cannot listen on socket");
     goto fail;
   }
   // get the resulting socket address, which may be different than what
   // we passed to bind.
   if (PR_GetSockName(mFD, &mAddr) != PR_SUCCESS)
   {
     NS_WARNING("cannot get socket name");
     goto fail;
   }
   // wait until AsyncListen is called before polling the socket for
   // client connections.
   return NS_OK;
 fail:
   nsresult rv = ErrorAccordingToNSPR(PR_GetError());
   Close();
   return rv;
 }
 NS_IMETHODIMP
 nsServerSocket::Close()
 {
   {
     MutexAutoLock lock(mLock);
     // we want to proxy the close operation to the socket thread if a listener
     // has been set.  otherwise, we should just close the socket here...
     if (!mListener)
     {
       if (mFD)
       {
         PR_Close(mFD);
         mFD = nullptr;
       }
       return NS_OK;
     }
   }
   return PostEvent(this, &nsServerSocket::OnMsgClose);
 }
 namespace {
 class ServerSocketListenerProxy MOZ_FINAL : public nsIServerSocketListener
 {
 public:
   ServerSocketListenerProxy(nsIServerSocketListener* aListener)
     : mListener(new nsMainThreadPtrHolder<nsIServerSocketListener>(aListener))
     , mTargetThread(do_GetCurrentThread())
   { }
   NS_DECL_THREADSAFE_ISUPPORTS
   NS_DECL_NSISERVERSOCKETLISTENER
   class OnSocketAcceptedRunnable : public nsRunnable
   {
   public:
     OnSocketAcceptedRunnable(const nsMainThreadPtrHandle<nsIServerSocketListener>& aListener,
                              nsIServerSocket* aServ,
                              nsISocketTransport* aTransport)
       : mListener(aListener)
       , mServ(aServ)
       , mTransport(aTransport)
     { }
     NS_DECL_NSIRUNNABLE
   private:
     nsMainThreadPtrHandle<nsIServerSocketListener> mListener;
     nsCOMPtr<nsIServerSocket> mServ;
     nsCOMPtr<nsISocketTransport> mTransport;
   };
   class OnStopListeningRunnable : public nsRunnable
   {
   public:
     OnStopListeningRunnable(const nsMainThreadPtrHandle<nsIServerSocketListener>& aListener,
                             nsIServerSocket* aServ,
                             nsresult aStatus)
       : mListener(aListener)
       , mServ(aServ)
       , mStatus(aStatus)
     { }
     NS_DECL_NSIRUNNABLE
   private:
     nsMainThreadPtrHandle<nsIServerSocketListener> mListener;
     nsCOMPtr<nsIServerSocket> mServ;
     nsresult mStatus;
   };
 private:
   nsMainThreadPtrHandle<nsIServerSocketListener> mListener;
   nsCOMPtr<nsIEventTarget> mTargetThread;
 };
 NS_IMPL_ISUPPORTS(ServerSocketListenerProxy,
                   nsIServerSocketListener)
 NS_IMETHODIMP
 ServerSocketListenerProxy::OnSocketAccepted(nsIServerSocket* aServ,
                                             nsISocketTransport* aTransport)
 {
   nsRefPtr<OnSocketAcceptedRunnable> r =
     new OnSocketAcceptedRunnable(mListener, aServ, aTransport);
   return mTargetThread->Dispatch(r, NS_DISPATCH_NORMAL);
 }
 NS_IMETHODIMP
 ServerSocketListenerProxy::OnStopListening(nsIServerSocket* aServ,
                                            nsresult aStatus)
 {
   nsRefPtr<OnStopListeningRunnable> r =
     new OnStopListeningRunnable(mListener, aServ, aStatus);
   return mTargetThread->Dispatch(r, NS_DISPATCH_NORMAL);
 }
 NS_IMETHODIMP
 ServerSocketListenerProxy::OnSocketAcceptedRunnable::Run()
 {
   mListener->OnSocketAccepted(mServ, mTransport);
   return NS_OK;
 }
 NS_IMETHODIMP
 ServerSocketListenerProxy::OnStopListeningRunnable::Run()
 {
   mListener->OnStopListening(mServ, mStatus);
   return NS_OK;
 }
 } // anonymous namespace
 NS_IMETHODIMP
 nsServerSocket::AsyncListen(nsIServerSocketListener *aListener)
 {
   // ensuring mFD implies ensuring mLock
   NS_ENSURE_TRUE(mFD, NS_ERROR_NOT_INITIALIZED);
   NS_ENSURE_TRUE(mListener == nullptr, NS_ERROR_IN_PROGRESS);
   {
     MutexAutoLock lock(mLock);
     mListener = new ServerSocketListenerProxy(aListener);
     mListenerTarget = NS_GetCurrentThread();
   }
   return PostEvent(this, &nsServerSocket::OnMsgAttach);
 }
 NS_IMETHODIMP
 nsServerSocket::GetPort(int32_t *aResult)
 {
   // no need to enter the lock here
   uint16_t port;
   if (mAddr.raw.family == PR_AF_INET)
     port = mAddr.inet.port;
   else if (mAddr.raw.family == PR_AF_INET6)
     port = mAddr.ipv6.port;
   else
     return NS_ERROR_FAILURE;
   *aResult = static_cast<int32_t>(NetworkEndian::readUint16(&port));
   return NS_OK;
 }
 NS_IMETHODIMP
 nsServerSocket::GetAddress(PRNetAddr *aResult)
 {
   // no need to enter the lock here
   memcpy(aResult, &mAddr, sizeof(mAddr));
   return NS_OK;
 }

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netwerk/base/src/nsServerSocket.cpp@b8a032363ba2 (annotated)

netwerk/base/src/nsServerSocket.cpp