1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4  * License, v. 2.0. If a copy of the MPL was not distributed with this
5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 
7 #ifndef __IPC_GLUE_GECKOCHILDPROCESSHOST_H__
8 #define __IPC_GLUE_GECKOCHILDPROCESSHOST_H__
9 
10 #include "base/file_path.h"
11 #include "base/process_util.h"
12 #include "base/waitable_event.h"
13 #include "chrome/common/child_process_host.h"
14 #include "chrome/common/ipc_message.h"
15 #include "mojo/core/ports/port_ref.h"
16 
17 #include "mozilla/ipc/FileDescriptor.h"
18 #include "mozilla/ipc/ScopedPort.h"
19 #include "mozilla/Atomics.h"
20 #include "mozilla/Buffer.h"
21 #include "mozilla/LinkedList.h"
22 #include "mozilla/Monitor.h"
23 #include "mozilla/MozPromise.h"
24 #include "mozilla/StaticMutex.h"
25 #include "mozilla/StaticPtr.h"
26 #include "mozilla/UniquePtr.h"
27 
28 #include "nsCOMPtr.h"
29 #include "nsExceptionHandler.h"
30 #include "nsXULAppAPI.h"  // for GeckoProcessType
31 #include "nsString.h"
32 
33 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
34 #  include "sandboxBroker.h"
35 #endif
36 
37 #if defined(XP_MACOSX) && defined(MOZ_SANDBOX)
38 #  include "mozilla/Sandbox.h"
39 #endif
40 
41 struct _MacSandboxInfo;
42 typedef _MacSandboxInfo MacSandboxInfo;
43 
44 namespace mozilla {
45 namespace ipc {
46 
47 struct LaunchError {};
48 typedef mozilla::MozPromise<base::ProcessHandle, LaunchError, false>
49     ProcessHandlePromise;
50 
51 struct LaunchResults {
52   base::ProcessHandle mHandle = 0;
53 #ifdef XP_MACOSX
54   task_t mChildTask = MACH_PORT_NULL;
55 #endif
56 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
57   RefPtr<AbstractSandboxBroker> mSandboxBroker;
58 #endif
59 };
60 typedef mozilla::MozPromise<LaunchResults, LaunchError, false>
61     ProcessLaunchPromise;
62 
63 class GeckoChildProcessHost : public ChildProcessHost,
64                               public LinkedListElement<GeckoChildProcessHost> {
65  protected:
66   typedef mozilla::Monitor Monitor;
67   typedef std::vector<std::string> StringVector;
68 
69  public:
70   typedef base::ProcessHandle ProcessHandle;
71 
72   explicit GeckoChildProcessHost(GeckoProcessType aProcessType,
73                                  bool aIsFileContent = false);
74 
75   // Causes the object to be deleted, on the I/O thread, after any
76   // pending asynchronous work (like launching) is complete.  This
77   // method can be called from any thread.  If called from the I/O
78   // thread itself, deletion won't happen until the event loop spins;
79   // otherwise, it could happen immediately.
80   //
81   // GeckoChildProcessHost instances must not be deleted except
82   // through this method.
83   void Destroy();
84 
85   static uint32_t GetUniqueID();
86 
87   // Call this before launching to set an environment variable for the
88   // child process.  The arguments must be UTF-8.
89   void SetEnv(const char* aKey, const char* aValue);
90 
91   // Does not block.  The IPC channel may not be initialized yet, and
92   // the child process may or may not have been created when this
93   // method returns.
94   bool AsyncLaunch(StringVector aExtraOpts = StringVector());
95 
96   virtual bool WaitUntilConnected(int32_t aTimeoutMs = 0);
97 
98   // Block until the IPC channel for our subprocess is initialized and
99   // the OS process is created.  The subprocess may or may not have
100   // connected back to us when this method returns.
101   //
102   // NB: on POSIX, this method is relatively cheap, and doesn't
103   // require disk IO.  On win32 however, it requires at least the
104   // analogue of stat().  This difference induces a semantic
105   // difference in this method: on POSIX, when we return, we know the
106   // subprocess has been created, but we don't know whether its
107   // executable image can be loaded.  On win32, we do know that when
108   // we return.  But we don't know if dynamic linking succeeded on
109   // either platform.
110   bool LaunchAndWaitForProcessHandle(StringVector aExtraOpts = StringVector());
111   bool WaitForProcessHandle();
112 
113   // Block until the child process has been created and it connects to
114   // the IPC channel, meaning it's fully initialized.  (Or until an
115   // error occurs.)
116   bool SyncLaunch(StringVector aExtraOpts = StringVector(),
117                   int32_t timeoutMs = 0);
118 
119   virtual void OnChannelConnected(int32_t peer_pid) override;
120   virtual void OnMessageReceived(IPC::Message&& aMsg) override;
121   virtual void OnChannelError() override;
122   virtual void GetQueuedMessages(std::queue<IPC::Message>& queue) override;
123 
124   // Resolves to the process handle when it's available (see
125   // LaunchAndWaitForProcessHandle); use with AsyncLaunch.
126   RefPtr<ProcessHandlePromise> WhenProcessHandleReady();
127 
128   void InitializeChannel(
129       const std::function<void(IPC::Channel*)>& aChannelReady);
130 
CanShutdown()131   virtual bool CanShutdown() override { return true; }
132 
GetChannel()133   IPC::Channel* GetChannel() { return channelp(); }
GetChannelId()134   ChannelId GetChannelId() { return channel_id(); }
135 
TakeInitialPort()136   ScopedPort TakeInitialPort() { return std::move(mInitialPort); }
137 
138   // Returns a "borrowed" handle to the child process - the handle returned
139   // by this function must not be closed by the caller.
GetChildProcessHandle()140   ProcessHandle GetChildProcessHandle() { return mChildProcessHandle; }
141 
GetProcessType()142   GeckoProcessType GetProcessType() { return mProcessType; }
143 
144 #ifdef XP_MACOSX
GetChildTask()145   task_t GetChildTask() { return mChildTask; }
146 #endif
147 
148 #ifdef XP_WIN
149 
AddHandleToShare(HANDLE aHandle)150   void AddHandleToShare(HANDLE aHandle) {
151     mLaunchOptions->handles_to_inherit.push_back(aHandle);
152   }
153 #else
AddFdToRemap(int aSrcFd,int aDstFd)154   void AddFdToRemap(int aSrcFd, int aDstFd) {
155     mLaunchOptions->fds_to_remap.push_back(std::make_pair(aSrcFd, aDstFd));
156   }
157 #endif
158 
159   /**
160    * Must run on the IO thread.  Cause the OS process to exit and
161    * ensure its OS resources are cleaned up.
162    */
163   void Join();
164 
165   // For bug 943174: Skip the EnsureProcessTerminated call in the destructor.
166   void SetAlreadyDead();
167 
168 #if defined(XP_MACOSX) && defined(MOZ_SANDBOX)
169   // Start the sandbox from the child process.
170   static bool StartMacSandbox(int aArgc, char** aArgv,
171                               std::string& aErrorMessage);
172 
173   // The sandbox type that will be use when sandboxing is
174   // enabled in the derived class and FillMacSandboxInfo
175   // has not been overridden.
GetDefaultMacSandboxType()176   static MacSandboxType GetDefaultMacSandboxType() {
177     return MacSandboxType_Utility;
178   };
179 
180   // Must be called before the process is launched. Determines if
181   // child processes will be launched with OS_ACTIVITY_MODE set to
182   // "disabled" or not. When |mDisableOSActivityMode| is set to true,
183   // child processes will be launched with OS_ACTIVITY_MODE
184   // disabled to avoid connection attempts to diagnosticd(8) which are
185   // blocked in child processes due to sandboxing.
186   void DisableOSActivityMode();
187 #endif
188   typedef std::function<void(GeckoChildProcessHost*)> GeckoProcessCallback;
189 
190   // Iterates over all instances and calls aCallback with each one of them.
191   // This method will lock any addition/removal of new processes
192   // so you need to make sure the callback is as fast as possible.
193   //
194   // To reiterate: the callbacks are executed synchronously.
195   static void GetAll(const GeckoProcessCallback& aCallback);
196 
197   friend class BaseProcessLauncher;
198   friend class PosixProcessLauncher;
199   friend class WindowsProcessLauncher;
200 
201  protected:
202   ~GeckoChildProcessHost();
203   GeckoProcessType mProcessType;
204   bool mIsFileContent;
205   Monitor mMonitor;
206   FilePath mProcessPath;
207   // GeckoChildProcessHost holds the launch options so they can be set
208   // up on the main thread using main-thread-only APIs like prefs, and
209   // then used for the actual launch on another thread.  This pointer
210   // is set to null to free the options after the child is launched.
211   UniquePtr<base::LaunchOptions> mLaunchOptions;
212   ScopedPort mInitialPort;
213 
214   // This value must be accessed while holding mMonitor.
215   enum {
216     // This object has been constructed, but the OS process has not
217     // yet.
218     CREATING_CHANNEL = 0,
219     // The IPC channel for our subprocess has been created, but the OS
220     // process has still not been created.
221     CHANNEL_INITIALIZED,
222     // The OS process has been created, but it hasn't yet connected to
223     // our IPC channel.
224     PROCESS_CREATED,
225     // The process is launched and connected to our IPC channel.  All
226     // is well.
227     PROCESS_CONNECTED,
228     PROCESS_ERROR
229   } mProcessState;
230 
231   void PrepareLaunch();
232 
233 #ifdef XP_WIN
234   void InitWindowsGroupID();
235   nsString mGroupId;
236   CrashReporter::WindowsErrorReportingData mWerData;
237 #  ifdef MOZ_SANDBOX
238   RefPtr<AbstractSandboxBroker> mSandboxBroker;
239   std::vector<std::wstring> mAllowedFilesRead;
240   bool mEnableSandboxLogging;
241   int32_t mSandboxLevel;
242 #  endif
243 #endif  // XP_WIN
244 
245   ProcessHandle mChildProcessHandle;
246 #if defined(OS_MACOSX)
247   task_t mChildTask;
248 #endif
249   RefPtr<ProcessHandlePromise> mHandlePromise;
250 
251 #if defined(XP_MACOSX) && defined(MOZ_SANDBOX)
252   bool mDisableOSActivityMode;
253 #endif
254 
255   bool OpenPrivilegedHandle(base::ProcessId aPid);
256 
257 #if defined(XP_MACOSX) && defined(MOZ_SANDBOX)
258   // Override this method to return true to launch the child process
259   // using the Mac utility (by default) sandbox. Override
260   // FillMacSandboxInfo() to change the sandbox type and settings.
IsMacSandboxLaunchEnabled()261   virtual bool IsMacSandboxLaunchEnabled() { return false; }
262 
263   // Fill a MacSandboxInfo to configure the sandbox
264   virtual bool FillMacSandboxInfo(MacSandboxInfo& aInfo);
265 
266   // Adds the command line arguments needed to enable
267   // sandboxing of the child process at startup before
268   // the child event loop is up.
269   virtual bool AppendMacSandboxParams(StringVector& aArgs);
270 #endif
271 
272  private:
273   DISALLOW_EVIL_CONSTRUCTORS(GeckoChildProcessHost);
274 
275   // Removes the instance from sGeckoChildProcessHosts
276   void RemoveFromProcessList();
277 
278   // In between launching the subprocess and handing off its IPC
279   // channel, there's a small window of time in which *we* might still
280   // be the channel listener, and receive messages.  That's bad
281   // because we have no idea what to do with those messages.  So queue
282   // them here until we hand off the eventual listener.
283   //
284   // FIXME/cjones: this strongly indicates bad design.  Shame on us.
285   std::queue<IPC::Message> mQueue;
286 
287   // Linux-Only. Set this up before we're called from a different thread.
288   nsCString mTmpDirName;
289   // Mac and Windows. Set this up before we're called from a different thread.
290   nsCOMPtr<nsIFile> mProfileDir;
291 
292   mozilla::Atomic<bool> mDestroying;
293 
294   static uint32_t sNextUniqueID;
295   static StaticAutoPtr<LinkedList<GeckoChildProcessHost>>
296       sGeckoChildProcessHosts;
297   static StaticMutex sMutex;
298 };
299 
300 nsCOMPtr<nsIEventTarget> GetIPCLauncher();
301 
302 } /* namespace ipc */
303 } /* namespace mozilla */
304 
305 #endif /* __IPC_GLUE_GECKOCHILDPROCESSHOST_H__ */
306