1    :  // Copyright 2012 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  
  15    :  #include <windows.h>
  16    :  
  17    :  #include "base/at_exit.h"
  18    :  #include "base/atomicops.h"
  19    :  #include "base/command_line.h"
  20    :  #include "base/logging.h"
  21    :  #include "syzygy/agent/asan/rtl_impl.h"
  22    :  #include "syzygy/agent/asan/runtime.h"
  23    :  #include "syzygy/agent/asan/runtime_util.h"
  24    :  #include "syzygy/agent/common/agent.h"
  25    :  #include "syzygy/common/logging.h"
  26    :  
  27    :  namespace {
  28    :  
  29    :  // Our AtExit manager required by base.
  30    :  base::AtExitManager* at_exit = nullptr;
  31    :  
  32    :  // The asan runtime manager.
  33    :  agent::asan::AsanRuntime* asan_runtime = nullptr;
  34    :  
  35  E :  void SetUpAtExitManager() {
  36  E :    DCHECK_EQ(static_cast<base::AtExitManager*>(nullptr), at_exit);
  37  E :    at_exit = new base::AtExitManager();
  38  E :    CHECK_NE(static_cast<base::AtExitManager*>(nullptr), at_exit);
  39  E :  }
  40    :  
  41  E :  void TearDownAtExitManager() {
  42  E :    DCHECK_NE(static_cast<base::AtExitManager*>(nullptr), at_exit);
  43  E :    delete at_exit;
  44  E :    at_exit = nullptr;
  45  E :  }
  46    :  
  47    :  }  // namespace
  48    :  
  49    :  extern "C" {
  50    :  
  51  E :  BOOL WINAPI DllMain(HMODULE instance, DWORD reason, LPVOID reserved) {
  52  E :    agent::common::InitializeCrt();
  53    :  
  54  E :    switch (reason) {
  55    :      case DLL_PROCESS_ATTACH: {
  56    :        // Create the At-Exit manager.
  57  E :        SetUpAtExitManager();
  58    :  
  59    :        // Disable logging. In the case of Chrome this is running in a sandboxed
  60    :        // process where logging to file doesn't help us any. In other cases the
  61    :        // log output will still go to console.
  62  E :        base::CommandLine::Init(0, NULL);
  63  E :        common::InitLoggingForDll(L"asan");
  64    :  
  65    :        // This runtime has no ability to disable instrumentation so can't
  66    :        // tolerate an initialization failure.
  67  E :        CHECK(SetUpAsanRuntime(&asan_runtime));
  68  E :        break;
  69    :      }
  70    :  
  71    :      case DLL_THREAD_ATTACH: {
  72  E :        agent::asan::AsanRuntime* runtime = agent::asan::AsanRuntime::runtime();
  73  E :        DCHECK_NE(static_cast<agent::asan::AsanRuntime*>(nullptr), runtime);
  74  E :        runtime->AddThreadId(::GetCurrentThreadId());
  75  E :        break;
  76    :      }
  77    :  
  78    :      case DLL_THREAD_DETACH:
  79    :        // Nothing to do here.
  80  i :        break;
  81    :  
  82    :      case DLL_PROCESS_DETACH: {
  83  E :        base::CommandLine::Reset();
  84    :        // This should be the last thing called in the agent DLL before it
  85    :        // gets unloaded. Everything should otherwise have been initialized
  86    :        // and we're now just cleaning it up again.
  87  E :        TearDownAsanRuntime(&asan_runtime);
  88  E :        TearDownAtExitManager();
  89  E :        break;
  90    :      }
  91    :  
  92    :      default:
  93  i :        NOTREACHED();
  94    :        break;
  95    :    }
  96    :  
  97  E :    return TRUE;
  98  E :  }
  99    :  
 100    :  }  // extern "C"