1    :  // Copyright 2015 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 "syzygy/agent/asan/hot_patching_asan_runtime.h"
  16    :  
  17    :  #include "base/command_line.h"
  18    :  #include "base/environment.h"
  19    :  #include "base/strings/utf_string_conversions.h"
  20    :  #include "syzygy/agent/asan/logger.h"
  21    :  #include "syzygy/trace/client/client_utils.h"
  22    :  #include "syzygy/trace/protocol/call_trace_defs.h"
  23    :  
  24    :  namespace agent {
  25    :  namespace asan {
  26    :  
  27    :  HotPatchingAsanRuntime::HotPatchingAsanRuntime() { }
  28    :  
  29    :  HotPatchingAsanRuntime::~HotPatchingAsanRuntime() { }
  30    :  
  31  E :  bool HotPatchingAsanRuntime::HotPatch(HINSTANCE instance) {
  32    :    logger_->Write("HPSyzyAsan: Started hot patching. Module: " +
  33    :        std::to_string(reinterpret_cast<int>(instance)) +
  34    :        " PID: " +
  35  E :        std::to_string(GetCurrentProcessId()));
  36    :  
  37  E :    if (hot_patched_modules_.count(instance)) {
  38  E :      logger_->Write("HPSyzyAsan - Already tried to hot patch, exiting.");
  39  E :      return true;
  40    :    }
  41  i :    hot_patched_modules_.insert(instance);
  42    :  
  43    :    // TODO(cseri): Do the hot patching.
  44  i :    logger_->Write("HPSyzyAsan: Hot patching not yet implemented.");
  45    :  
  46  i :    return true;
  47  E :  }
  48    :  
  49    :  void HotPatchingAsanRuntime::SetUp() {
  50    :    SetUpLogger();
  51    :  
  52    :    logger_->Write("HPSyzyAsan: Runtime loaded.");
  53    :  }
  54    :  
  55    :  void HotPatchingAsanRuntime::SetUpLogger() {
  56    :    // Setup variables we're going to use.
  57    :    scoped_ptr<base::Environment> env(base::Environment::Create());
  58    :    scoped_ptr<AsanLogger> client(new AsanLogger);
  59    :    CHECK(env.get() != NULL);
  60    :    CHECK(client.get() != NULL);
  61    :  
  62    :    // Initialize the client.
  63    :    client->set_instance_id(
  64    :        base::UTF8ToWide(trace::client::GetInstanceIdForThisModule()));
  65    :    client->Init();
  66    :  
  67    :    // Register the client singleton instance.
  68    :    logger_.reset(client.release());
  69    :  }
  70    :  
  71    :  void WINAPI HotPatchingAsanRuntime::DllMainEntryHook(
  72    :      agent::EntryFrame* entry_frame,
  73    :      FuncAddr function) {
  74    :    HINSTANCE instance = reinterpret_cast<HINSTANCE>(entry_frame->args[0]);
  75    :    DWORD reason = entry_frame->args[1];
  76    :  
  77    :    switch (reason) {
  78    :      case DLL_PROCESS_ATTACH: {
  79    :        HotPatchingAsanRuntime::GetInstance()->HotPatch(instance);
  80    :        break;
  81    :      }
  82    :  
  83    :      case DLL_THREAD_ATTACH:
  84    :        // Nothing to do here.
  85    :        break;
  86    :  
  87    :      case DLL_THREAD_DETACH:
  88    :        // Nothing to do here.
  89    :        break;
  90    :  
  91    :      case DLL_PROCESS_DETACH:
  92    :        // Nothing to do here.
  93    :        break;
  94    :  
  95    :      default:
  96    :        NOTREACHED();
  97    :        break;
  98    :    }
  99    :  }
 100    :  
 101    :  }  // namespace asan
 102    :  }  // namespace agent
 103    :  
 104    :  extern "C" {
 105    :  
 106    :  agent::asan::HotPatchingAsanRuntime* hp_asan_GetActiveHotPatchingAsanRuntime() {
 107    :    return agent::asan::HotPatchingAsanRuntime::GetInstance();
 108    :  }
 109    :  
 110    :  }