diff options
| -rw-r--r-- | courgette/disassembler_elf_32_x86.cc | 110 | ||||
| -rw-r--r-- | courgette/disassembler_win32_x86.cc | 51 |
2 files changed, 72 insertions, 89 deletions
diff --git a/courgette/disassembler_elf_32_x86.cc b/courgette/disassembler_elf_32_x86.cc index 5f3ba95..871cdb7 100644 --- a/courgette/disassembler_elf_32_x86.cc +++ b/courgette/disassembler_elf_32_x86.cc @@ -255,19 +255,17 @@ CheckBool DisassemblerElf32X86::RVAsToOffsets(std::vector<RVA>* rvas, } CheckBool DisassemblerElf32X86::ParseFile(AssemblyProgram* program) { - bool ok = true; - // Walk all the bytes in the file, whether or not in a section. uint32 file_offset = 0; std::vector<size_t> abs_offsets; std::vector<size_t> rel_offsets; - if (ok) - ok = RVAsToOffsets(&abs32_locations_, &abs_offsets); + if (!RVAsToOffsets(&abs32_locations_, &abs_offsets)) + return false; - if (ok) - ok = RVAsToOffsets(&rel32_locations_, &rel_offsets); + if (!RVAsToOffsets(&rel32_locations_, &rel_offsets)) + return false; std::vector<size_t>::iterator current_abs_offset = abs_offsets.begin(); std::vector<size_t>::iterator current_rel_offset = rel_offsets.begin(); @@ -276,34 +274,30 @@ CheckBool DisassemblerElf32X86::ParseFile(AssemblyProgram* program) { std::vector<size_t>::iterator end_rel_offset = rel_offsets.end(); for (int section_id = 0; - ok && (section_id < SectionHeaderCount()); + section_id < SectionHeaderCount(); section_id++) { const Elf32_Shdr *section_header = SectionHeader(section_id); - if (ok) { - ok = ParseSimpleRegion(file_offset, - section_header->sh_offset, - program); - file_offset = section_header->sh_offset; - } + if (!ParseSimpleRegion(file_offset, + section_header->sh_offset, + program)) + return false; + file_offset = section_header->sh_offset; switch (section_header->sh_type) { case SHT_REL: - if (ok) { - ok = ParseRelocationSection(section_header, program); - file_offset = section_header->sh_offset + section_header->sh_size; - } + if (!ParseRelocationSection(section_header, program)) + return false; + file_offset = section_header->sh_offset + section_header->sh_size; break; case SHT_PROGBITS: - if (ok) { - ok = ParseProgbitsSection(section_header, - ¤t_abs_offset, end_abs_offset, - ¤t_rel_offset, end_rel_offset, - program); - file_offset = section_header->sh_offset + section_header->sh_size; - } - + if (!ParseProgbitsSection(section_header, + ¤t_abs_offset, end_abs_offset, + ¤t_rel_offset, end_rel_offset, + program)) + return false; + file_offset = section_header->sh_offset + section_header->sh_size; break; default: break; @@ -311,16 +305,13 @@ CheckBool DisassemblerElf32X86::ParseFile(AssemblyProgram* program) { } // Rest of the file past the last section - if (ok) { - ok = ParseSimpleRegion(file_offset, - length(), - program); - } + if (!ParseSimpleRegion(file_offset, + length(), + program)) + return false; // Make certain we consume all of the relocations as expected - ok = ok && (current_abs_offset == end_abs_offset); - - return ok; + return (current_abs_offset == end_abs_offset); } CheckBool DisassemblerElf32X86::ParseRelocationSection( @@ -342,7 +333,6 @@ CheckBool DisassemblerElf32X86::ParseRelocationSection( // all of our R_386_RELATIVE entries in the expected order followed // by assorted other entries we can't use special handling for. - bool ok = true; bool match = true; // Walk all the bytes in the section, matching relocation table or not @@ -370,15 +360,12 @@ CheckBool DisassemblerElf32X86::ParseRelocationSection( if (match) { // Skip over relocation tables - ok = program->EmitElfRelocationInstruction(); + if (!program->EmitElfRelocationInstruction()) + return false; file_offset += sizeof(Elf32_Rel) * abs32_locations_.size(); } - if (ok) { - ok = ParseSimpleRegion(file_offset, section_end, program); - } - - return ok; + return ParseSimpleRegion(file_offset, section_end, program); } CheckBool DisassemblerElf32X86::ParseProgbitsSection( @@ -389,22 +376,20 @@ CheckBool DisassemblerElf32X86::ParseProgbitsSection( std::vector<size_t>::iterator end_rel_offset, AssemblyProgram* program) { - bool ok = true; - // Walk all the bytes in the file, whether or not in a section. size_t file_offset = section_header->sh_offset; size_t section_end = section_header->sh_offset + section_header->sh_size; Elf32_Addr origin = section_header->sh_addr; size_t origin_offset = section_header->sh_offset; - ok = program->EmitOriginInstruction(origin); + if (!program->EmitOriginInstruction(origin)) + return false; - while (ok && file_offset < section_end) { + while (file_offset < section_end) { if (*current_abs_offset != end_abs_offset && - file_offset > **current_abs_offset) { - ok = false; - } + file_offset > **current_abs_offset) + return false; while (*current_rel_offset != end_rel_offset && file_offset > **current_rel_offset) { @@ -424,28 +409,28 @@ CheckBool DisassemblerElf32X86::ParseProgbitsSection( next_relocation > (**current_rel_offset + 3)) next_relocation = **current_rel_offset; - if (ok && (next_relocation > file_offset)) { - ok = ParseSimpleRegion(file_offset, next_relocation, program); + if (next_relocation > file_offset) { + if (!ParseSimpleRegion(file_offset, next_relocation, program)) + return false; file_offset = next_relocation; continue; } - if (ok && - *current_abs_offset != end_abs_offset && + if (*current_abs_offset != end_abs_offset && file_offset == **current_abs_offset) { const uint8* p = OffsetToPointer(file_offset); RVA target_rva = Read32LittleEndian(p); - ok = program->EmitAbs32(program->FindOrMakeAbs32Label(target_rva)); + if (!program->EmitAbs32(program->FindOrMakeAbs32Label(target_rva))) + return false; file_offset += sizeof(RVA); (*current_abs_offset)++; continue; } - if (ok && - *current_rel_offset != end_rel_offset && + if (*current_rel_offset != end_rel_offset && file_offset == **current_rel_offset) { const uint8* p = OffsetToPointer(file_offset); @@ -455,7 +440,8 @@ CheckBool DisassemblerElf32X86::ParseProgbitsSection( RVA target_rva = (RVA)(origin + (file_offset - origin_offset) + 4 + relative_target); - ok = program->EmitRel32(program->FindOrMakeRel32Label(target_rva)); + if (!program->EmitRel32(program->FindOrMakeRel32Label(target_rva))) + return false; file_offset += sizeof(RVA); (*current_rel_offset)++; continue; @@ -463,11 +449,7 @@ CheckBool DisassemblerElf32X86::ParseProgbitsSection( } // Rest of the section (if any) - if (ok) { - ok = ParseSimpleRegion(file_offset, section_end, program); - } - - return ok; + return ParseSimpleRegion(file_offset, section_end, program); } CheckBool DisassemblerElf32X86::ParseSimpleRegion( @@ -480,13 +462,13 @@ CheckBool DisassemblerElf32X86::ParseSimpleRegion( const uint8* p = start; - bool ok = true; - while (p < end && ok) { - ok = program->EmitByteInstruction(*p); + while (p < end) { + if (!program->EmitByteInstruction(*p)) + return false; ++p; } - return ok; + return true; } CheckBool DisassemblerElf32X86::ParseAbs32Relocs() { diff --git a/courgette/disassembler_win32_x86.cc b/courgette/disassembler_win32_x86.cc index 39cb695..10d7e4b 100644 --- a/courgette/disassembler_win32_x86.cc +++ b/courgette/disassembler_win32_x86.cc @@ -336,10 +336,9 @@ std::string DisassemblerWin32X86::SectionName(const Section* section) { } CheckBool DisassemblerWin32X86::ParseFile(AssemblyProgram* program) { - bool ok = true; // Walk all the bytes in the file, whether or not in a section. uint32 file_offset = 0; - while (ok && file_offset < length()) { + while (file_offset < length()) { const Section* section = FindNextSection(file_offset); if (section == NULL) { // No more sections. There should not be extra stuff following last @@ -349,15 +348,16 @@ CheckBool DisassemblerWin32X86::ParseFile(AssemblyProgram* program) { } if (file_offset < section->file_offset_of_raw_data) { uint32 section_start_offset = section->file_offset_of_raw_data; - ok = ParseNonSectionFileRegion(file_offset, section_start_offset, - program); + if(!ParseNonSectionFileRegion(file_offset, section_start_offset, + program)) + return false; + file_offset = section_start_offset; } - if (ok) { - uint32 end = file_offset + section->size_of_raw_data; - ok = ParseFileRegion(section, file_offset, end, program); - file_offset = end; - } + uint32 end = file_offset + section->size_of_raw_data; + if (!ParseFileRegion(section, file_offset, end, program)) + return false; + file_offset = end; } #if COURGETTE_HISTOGRAM_TARGETS @@ -365,7 +365,7 @@ CheckBool DisassemblerWin32X86::ParseFile(AssemblyProgram* program) { HistogramTargets("rel32 relocs", rel32_target_rvas_); #endif - return ok; + return true; } bool DisassemblerWin32X86::ParseAbs32Relocs() { @@ -523,13 +523,13 @@ CheckBool DisassemblerWin32X86::ParseNonSectionFileRegion( const uint8* p = start; - bool ok = true; - while (p < end && ok) { - ok = program->EmitByteInstruction(*p); + while (p < end) { + if (!program->EmitByteInstruction(*p)) + return false; ++p; } - return ok; + return true; } CheckBool DisassemblerWin32X86::ParseFileRegion( @@ -551,20 +551,20 @@ CheckBool DisassemblerWin32X86::ParseFileRegion( std::vector<RVA>::iterator rel32_pos = rel32_locations_.begin(); std::vector<RVA>::iterator abs32_pos = abs32_locations_.begin(); - bool ok = program->EmitOriginInstruction(start_rva); + if (!program->EmitOriginInstruction(start_rva)) + return false; const uint8* p = start_pointer; - while (ok && p < end_pointer) { + while (p < end_pointer) { RVA current_rva = static_cast<RVA>(p - adjust_pointer_to_rva); // The base relocation table is usually in the .relocs section, but it could // actually be anywhere. Make sure we skip it because we will regenerate it // during assembly. if (current_rva == relocs_start_rva) { - ok = program->EmitPeRelocsInstruction(); - if (!ok) - break; + if (!program->EmitPeRelocsInstruction()) + return false; uint32 relocs_size = base_relocation_table().size_; if (relocs_size) { p += relocs_size; @@ -580,9 +580,8 @@ CheckBool DisassemblerWin32X86::ParseFileRegion( RVA target_rva = target_address - image_base(); // TODO(sra): target could be Label+offset. It is not clear how to guess // which it might be. We assume offset==0. - ok = program->EmitAbs32(program->FindOrMakeAbs32Label(target_rva)); - if (!ok) - break; + if (!program->EmitAbs32(program->FindOrMakeAbs32Label(target_rva))) + return false; p += 4; continue; } @@ -592,7 +591,8 @@ CheckBool DisassemblerWin32X86::ParseFileRegion( if (rel32_pos != rel32_locations_.end() && *rel32_pos == current_rva) { RVA target_rva = current_rva + 4 + Read32LittleEndian(p); - ok = program->EmitRel32(program->FindOrMakeRel32Label(target_rva)); + if (!program->EmitRel32(program->FindOrMakeRel32Label(target_rva))) + return false; p += 4; continue; } @@ -606,11 +606,12 @@ CheckBool DisassemblerWin32X86::ParseFileRegion( } } - ok = program->EmitByteInstruction(*p); + if (!program->EmitByteInstruction(*p)) + return false; p += 1; } - return ok; + return true; } #if COURGETTE_HISTOGRAM_TARGETS |