dom/ipc/ContentProcess.cpp

   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 #include "mozilla/ipc/IOThreadChild.h"
   8
   9 #include "ContentProcess.h"
  10 #include "base/shared_memory.h"
  11 #include "mozilla/Preferences.h"
  12
  13 #if defined(XP_MACOSX) && defined(MOZ_SANDBOX)
  14 #  include <stdlib.h>
  15 #  include "mozilla/Sandbox.h"
  16 #endif
  17
  18 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
  19 #  include "mozilla/WindowsProcessMitigations.h"
  20 #endif
  21
  22 #if (defined(XP_WIN) || defined(XP_MACOSX)) && defined(MOZ_SANDBOX)
  23 #  include "mozilla/SandboxSettings.h"
  24 #  include "nsAppDirectoryServiceDefs.h"
  25 #  include "nsDirectoryService.h"
  26 #  include "nsDirectoryServiceDefs.h"
  27 #endif
  28
  29 #include "nsAppRunner.h"
  30 #include "mozilla/ipc/BackgroundChild.h"
  31 #include "mozilla/ipc/ProcessUtils.h"
  32 #include "mozilla/GeckoArgs.h"
  33
  34 using mozilla::ipc::IOThreadChild;
  35
  36 namespace mozilla::dom {
  37
  38 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
  39 static void SetTmpEnvironmentVariable(nsIFile* aValue) {
  40   // Save the TMP environment variable so that is is picked up by GetTempPath().
  41   // Note that we specifically write to the TMP variable, as that is the first
  42   // variable that is checked by GetTempPath() to determine its output.
  43   nsAutoString fullTmpPath;
  44   nsresult rv = aValue->GetPath(fullTmpPath);
  45   if (NS_WARN_IF(NS_FAILED(rv))) {
  46     return;
  47   }
  48   Unused << NS_WARN_IF(!SetEnvironmentVariableW(L"TMP", fullTmpPath.get()));
  49   // We also set TEMP in case there is naughty third-party code that is
  50   // referencing the environment variable directly.
  51   Unused << NS_WARN_IF(!SetEnvironmentVariableW(L"TEMP", fullTmpPath.get()));
  52 }
  53 #endif
  54
  55 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
  56 static void SetUpSandboxEnvironment() {
  57   MOZ_ASSERT(
  58       nsDirectoryService::gService,
  59       "SetUpSandboxEnvironment relies on nsDirectoryService being initialized");
  60
  61   // On Windows, a sandbox-writable temp directory is used whenever the sandbox
  62   // is enabled, except when win32k is locked down when we no longer require a
  63   // temp directory.
  64   if (!IsContentSandboxEnabled() || IsWin32kLockedDown()) {
  65     return;
  66   }
  67
  68   nsCOMPtr<nsIFile> sandboxedContentTemp;
  69   nsresult rv = nsDirectoryService::gService->Get(
  70       NS_APP_CONTENT_PROCESS_TEMP_DIR, NS_GET_IID(nsIFile),
  71       getter_AddRefs(sandboxedContentTemp));
  72   if (NS_WARN_IF(NS_FAILED(rv))) {
  73     return;
  74   }
  75
  76   // Change the gecko defined temp directory to our sandbox-writable one.
  77   // Undefine returns a failure if the property is not already set.
  78   Unused << nsDirectoryService::gService->Undefine(NS_OS_TEMP_DIR);
  79   rv = nsDirectoryService::gService->Set(NS_OS_TEMP_DIR, sandboxedContentTemp);
  80   if (NS_WARN_IF(NS_FAILED(rv))) {
  81     return;
  82   }
  83
  84   SetTmpEnvironmentVariable(sandboxedContentTemp);
  85 }
  86 #endif
  87
  88 bool ContentProcess::Init(int aArgc, char* aArgv[]) {
  89   Maybe<uint64_t> childID = geckoargs::sChildID.Get(aArgc, aArgv);
  90   Maybe<bool> isForBrowser = Nothing();
  91   Maybe<const char*> parentBuildID =
  92       geckoargs::sParentBuildID.Get(aArgc, aArgv);
  93   Maybe<uint64_t> jsInitHandle;
  94   Maybe<uint64_t> jsInitLen = geckoargs::sJsInitLen.Get(aArgc, aArgv);
  95 #if defined(XP_MACOSX) && defined(MOZ_SANDBOX)
  96   nsCOMPtr<nsIFile> profileDir;
  97 #endif
  98
  99   Maybe<const char*> appDir = geckoargs::sAppDir.Get(aArgc, aArgv);
 100   if (appDir.isSome()) {
 101     mXREEmbed.SetAppDir(nsDependentCString(*appDir));
 102   }
 103
 104   Maybe<bool> safeMode = geckoargs::sSafeMode.Get(aArgc, aArgv);
 105   if (safeMode.isSome()) {
 106     gSafeMode = *safeMode;
 107   }
 108
 109   Maybe<bool> isForBrowerParam = geckoargs::sIsForBrowser.Get(aArgc, aArgv);
 110   Maybe<bool> notForBrowserParam = geckoargs::sNotForBrowser.Get(aArgc, aArgv);
 111   if (isForBrowerParam.isSome()) {
 112     isForBrowser = Some(true);
 113   }
 114   if (notForBrowserParam.isSome()) {
 115     isForBrowser = Some(false);
 116   }
 117
 118   // command line: [-jsInitHandle handle] -jsInitLen length
 119 #ifdef XP_WIN
 120   jsInitHandle = geckoargs::sJsInitHandle.Get(aArgc, aArgv);
 121 #endif
 122
 123 #if defined(XP_MACOSX) && defined(MOZ_SANDBOX)
 124   bool flag;
 125   Maybe<const char*> profile = geckoargs::sProfile.Get(aArgc, aArgv);
 126   // xpcshell self-test on macOS will hit this, so check isSome() otherwise
 127   // Maybe<> assertions will MOZ_CRASH() us.
 128   if (profile.isSome()) {
 129     nsresult rv = XRE_GetFileFromPath(*profile, getter_AddRefs(profileDir));
 130     if (NS_FAILED(rv) || NS_FAILED(profileDir->Exists(&flag)) || !flag) {
 131       NS_WARNING("Invalid profile directory passed to content process.");
 132       profileDir = nullptr;
 133     }
 134   } else {
 135     NS_WARNING("No profile directory passed to content process.");
 136   }
 137 #endif /* XP_MACOSX && MOZ_SANDBOX */
 138
 139   // Did we find all the mandatory flags?
 140   if (childID.isNothing() || isForBrowser.isNothing() ||
 141       parentBuildID.isNothing()) {
 142     return false;
 143   }
 144
 145   if (!ProcessChild::InitPrefs(aArgc, aArgv)) {
 146     return false;
 147   }
 148
 149   if (!::mozilla::ipc::ImportSharedJSInit(jsInitHandle.valueOr(0),
 150                                           jsInitLen.valueOr(0))) {
 151     return false;
 152   }
 153
 154   mContent.Init(TakeInitialEndpoint(), *parentBuildID, *childID, *isForBrowser);
 155
 156   mXREEmbed.Start();
 157 #if (defined(XP_MACOSX)) && defined(MOZ_SANDBOX)
 158   mContent.SetProfileDir(profileDir);
 159 #  if defined(DEBUG)
 160   if (IsContentSandboxEnabled()) {
 161     AssertMacSandboxEnabled();
 162   }
 163 #  endif /* DEBUG */
 164 #endif   /* XP_MACOSX && MOZ_SANDBOX */
 165
 166 #if defined(XP_WIN) && defined(MOZ_SANDBOX)
 167   SetUpSandboxEnvironment();
 168 #endif
 169
 170   // Do this as early as possible to get the parent process to initialize the
 171   // background thread since we'll likely need database information very soon.
 172   mozilla::ipc::BackgroundChild::Startup();
 173   mozilla::ipc::BackgroundChild::InitContentStarter(&mContent);
 174
 175   return true;
 176 }
 177
 178 // Note: CleanUp() never gets called in non-debug builds because we exit early
 179 // in ContentChild::ActorDestroy().
 180 void ContentProcess::CleanUp() { mXREEmbed.Stop(); }
 181
 182 }  // namespace mozilla::dom