1    :  // Copyright 2014 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    :  // Utility functions used by the Asan check functions..
  16    :  #ifndef SYZYGY_AGENT_ASAN_RTL_UTILS_H_
  17    :  #define SYZYGY_AGENT_ASAN_RTL_UTILS_H_
  18    :  
  19    :  #include <windows.h>
  20    :  
  21    :  #include "syzygy/agent/asan/error_info.h"
  22    :  
  23    :  namespace agent {
  24    :  namespace asan {
  25    :  
  26    :  // Forward declarations.
  27    :  class AsanRuntime;
  28    :  class Shadow;
  29    :  
  30    :  // Contents of the registers before calling the Asan memory check function.
  31    :  // Note: the order of fields is significant!
  32    :  #pragma pack(push, 1)
  33    :  struct AsanContext {
  34    :  #ifdef _WIN64
  35    :    // TODO(loskutov): add more x64 registers or eliminate this piece of code.
  36    :    size_t original_rdi;
  37    :    size_t original_rsi;
  38    :    size_t original_rbp;
  39    :    size_t original_rsp;
  40    :    size_t original_rbx;
  41    :    size_t original_rdx;
  42    :    size_t original_rcx;
  43    :    size_t original_rax;
  44    :    DWORD original_eflags;
  45    :    size_t original_rip;
  46    :  #else
  47    :    DWORD original_edi;
  48    :    DWORD original_esi;
  49    :    DWORD original_ebp;
  50    :    DWORD original_esp;
  51    :    DWORD original_ebx;
  52    :    DWORD original_edx;
  53    :    DWORD original_ecx;
  54    :    DWORD original_eax;
  55    :    DWORD original_eflags;
  56    :    DWORD original_eip;
  57    :  #endif
  58    :  };
  59    :  #pragma pack(pop)
  60    :  
  61    :  // Set the AsanRuntime instance that should be used to report the crash.
  62    :  // @param runtime The runtime instance to use.
  63    :  void SetAsanRuntimeInstance(AsanRuntime* runtime);
  64    :  
  65    :  // Convert a CONTEXT struct to an Asan context.
  66    :  // @param context The context to convert.
  67    :  // @param asan_context Receives the Asan context.
  68    :  void ContextToAsanContext(const CONTEXT& context, AsanContext* asan_context);
  69    :  
  70    :  // Report a bad access to the memory.
  71    :  // @param location The memory address of the access.
  72    :  // @param access_mode The mode of the access.
  73    :  // @param access_size The size of the access.
  74    :  // @param asan_context The context of the access.
  75    :  void ReportBadMemoryAccess(const void* location,
  76    :                             AccessMode access_mode,
  77    :                             size_t access_size,
  78    :                             const AsanContext& asan_context);
  79    :  
  80    :  // Report an invalid access to @p location.
  81    :  // @param location The memory address of the access.
  82    :  // @param access_mode The mode of the access.
  83    :  void ReportBadAccess(const void* location, AccessMode access_mode);
  84    :  
  85    :  // Test that a memory range is accessible. Report an error if it's not.
  86    :  // @param shadow The shadow memory to use.
  87    :  // @param memory The pointer to the beginning of the memory range that we want
  88    :  //     to check.
  89    :  // @param size The size of the memory range that we want to check.
  90    :  // @param access_mode The access mode.
  91    :  void TestMemoryRange(Shadow* shadow,
  92    :                       const uint8_t* memory,
  93    :                       size_t size,
  94    :                       AccessMode access_mode);
  95    :  
  96    :  // Helper function to test if the memory range of a given structure is
  97    :  // accessible.
  98    :  // @tparam T the type of the structure to be tested.
  99    :  // @param shadow The shadow memory to use.
 100    :  // @param structure A pointer to this structure.
 101    :  // @param access mode The access mode.
 102    :  template <typename T>
 103  E :  void TestStructure(Shadow* shadow, const T* structure, AccessMode access_mode) {
 104  E :    TestMemoryRange(shadow, reinterpret_cast<const uint8_t*>(structure),
 105    :                    sizeof(T), access_mode);
 106  E :  }
 107    :  
 108    :  }  // namespace asan
 109    :  }  // namespace agent
 110    :  
 111    :  
 112    :  #endif  // SYZYGY_AGENT_ASAN_RTL_UTILS_H_