1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef COURGETTE_DISASSEMBLER_WIN32_X86_H_ 6 #define COURGETTE_DISASSEMBLER_WIN32_X86_H_ 7 8 #include "base/basictypes.h" 9 #include "courgette/disassembler.h" 10 #include "courgette/memory_allocator.h" 11 #include "courgette/types_win_pe.h" 12 13 namespace courgette { 14 15 class AssemblyProgram; 16 17 class DisassemblerWin32X86 : public Disassembler { 18 public: 19 explicit DisassemblerWin32X86(const void* start, size_t length); 20 21 virtual ExecutableType kind() { return EXE_WIN_32_X86; } 22 23 // Returns 'true' if the buffer appears to point to a Windows 32 bit 24 // executable, 'false' otherwise. If ParseHeader() succeeds, other member 25 // functions may be called. 26 virtual bool ParseHeader(); 27 28 virtual bool Disassemble(AssemblyProgram* target); 29 30 // 31 // Exposed for test purposes 32 // 33 34 bool has_text_section() const { return has_text_section_; } 35 uint32 size_of_code() const { return size_of_code_; } 36 bool is_32bit() const { return !is_PE32_plus_; } 37 38 // Returns 'true' if the base relocation table can be parsed. 39 // Output is a vector of the RVAs corresponding to locations within executable 40 // that are listed in the base relocation table. 41 bool ParseRelocs(std::vector<RVA> *addresses); 42 43 // Returns Section containing the relative virtual address, or NULL if none. 44 const Section* RVAToSection(RVA rva) const; 45 46 static const int kNoOffset = -1; 47 // Returns kNoOffset if there is no file offset corresponding to 'rva'. 48 int RVAToFileOffset(RVA rva) const; 49 50 // Returns same as FileOffsetToPointer(RVAToFileOffset(rva)) except that NULL 51 // is returned if there is no file offset corresponding to 'rva'. 52 const uint8* RVAToPointer(RVA rva) const; 53 54 static std::string SectionName(const Section* section); 55 56 protected: 57 CheckBool ParseFile(AssemblyProgram* target) WARN_UNUSED_RESULT; 58 bool ParseAbs32Relocs(); 59 void ParseRel32RelocsFromSections(); 60 void ParseRel32RelocsFromSection(const Section* section); 61 62 CheckBool ParseNonSectionFileRegion(uint32 start_file_offset, 63 uint32 end_file_offset, AssemblyProgram* program) WARN_UNUSED_RESULT; 64 CheckBool ParseFileRegion(const Section* section, 65 uint32 start_file_offset, uint32 end_file_offset, 66 AssemblyProgram* program) WARN_UNUSED_RESULT; 67 68 #if COURGETTE_HISTOGRAM_TARGETS 69 void HistogramTargets(const char* kind, const std::map<RVA, int>& map); 70 #endif 71 72 // Most addresses are represented as 32-bit RVAs. The one address we can't 73 // do this with is the image base address. 'image_base' is valid only for 74 // 32-bit executables. 'image_base_64' is valid for 32- and 64-bit executable. 75 uint32 image_base() const { return static_cast<uint32>(image_base_); } 76 77 const ImageDataDirectory& base_relocation_table() const { 78 return base_relocation_table_; 79 } 80 81 bool IsValidRVA(RVA rva) const { return rva < size_of_image_; } 82 83 // Returns description of the RVA, e.g. ".text+0x1243". For debugging only. 84 std::string DescribeRVA(RVA rva) const; 85 86 // Finds the first section at file_offset or above. Does not return sections 87 // that have no raw bytes in the file. 88 const Section* FindNextSection(uint32 file_offset) const; 89 90 // There are 2 'coordinate systems' for reasoning about executables. 91 // FileOffset - the the offset within a single .EXE or .DLL *file*. 92 // RVA - relative virtual address (offset within *loaded image*) 93 // FileOffsetToRVA and RVAToFileOffset convert between these representations. 94 95 RVA FileOffsetToRVA(uint32 offset) const; 96 97 98 private: 99 100 bool ReadDataDirectory(int index, ImageDataDirectory* dir); 101 102 bool incomplete_disassembly_; // 'true' if can leave out 'uninteresting' bits 103 104 std::vector<RVA> abs32_locations_; 105 std::vector<RVA> rel32_locations_; 106 107 // 108 // Fields that are always valid. 109 // 110 111 // 112 // Information that is valid after successful ParseHeader. 113 // 114 bool is_PE32_plus_; // PE32_plus is for 64 bit executables. 115 116 // Location and size of IMAGE_OPTIONAL_HEADER in the buffer. 117 const uint8 *optional_header_; 118 uint16 size_of_optional_header_; 119 uint16 offset_of_data_directories_; 120 121 uint16 machine_type_; 122 uint16 number_of_sections_; 123 const Section *sections_; 124 bool has_text_section_; 125 126 uint32 size_of_code_; 127 uint32 size_of_initialized_data_; 128 uint32 size_of_uninitialized_data_; 129 RVA base_of_code_; 130 RVA base_of_data_; 131 132 uint64 image_base_; // range limited to 32 bits for 32 bit executable 133 uint32 size_of_image_; 134 int number_of_data_directories_; 135 136 ImageDataDirectory export_table_; 137 ImageDataDirectory import_table_; 138 ImageDataDirectory resource_table_; 139 ImageDataDirectory exception_table_; 140 ImageDataDirectory base_relocation_table_; 141 ImageDataDirectory bound_import_table_; 142 ImageDataDirectory import_address_table_; 143 ImageDataDirectory delay_import_descriptor_; 144 ImageDataDirectory clr_runtime_header_; 145 146 #if COURGETTE_HISTOGRAM_TARGETS 147 std::map<RVA, int> abs32_target_rvas_; 148 std::map<RVA, int> rel32_target_rvas_; 149 #endif 150 151 152 DISALLOW_COPY_AND_ASSIGN(DisassemblerWin32X86); 153 }; 154 155 } // namespace courgette 156 #endif // COURGETTE_DISASSEMBLER_WIN32_X86_H_ 157