diff options
Diffstat (limited to 'contrib/llvm/lib/Object/COFFObjectFile.cpp')
| -rw-r--r-- | contrib/llvm/lib/Object/COFFObjectFile.cpp | 455 |
1 files changed, 455 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Object/COFFObjectFile.cpp b/contrib/llvm/lib/Object/COFFObjectFile.cpp new file mode 100644 index 0000000..07de6bc --- /dev/null +++ b/contrib/llvm/lib/Object/COFFObjectFile.cpp @@ -0,0 +1,455 @@ +//===- COFFObjectFile.cpp - COFF object file implementation -----*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file declares the COFFObjectFile class. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Object/COFF.h" +#include "llvm/ADT/StringSwitch.h" +#include "llvm/ADT/Triple.h" + +using namespace llvm; +using namespace object; + +namespace { +using support::ulittle8_t; +using support::ulittle16_t; +using support::ulittle32_t; +using support::little16_t; +} + +namespace { +// Returns false if size is greater than the buffer size. And sets ec. +bool checkSize(const MemoryBuffer *m, error_code &ec, uint64_t size) { + if (m->getBufferSize() < size) { + ec = object_error::unexpected_eof; + return false; + } + return true; +} + +// Returns false if any bytes in [addr, addr + size) fall outsize of m. +bool checkAddr(const MemoryBuffer *m, + error_code &ec, + uintptr_t addr, + uint64_t size) { + if (addr + size < addr || + addr + size < size || + addr + size > uintptr_t(m->getBufferEnd())) { + ec = object_error::unexpected_eof; + return false; + } + return true; +} +} + +const coff_symbol *COFFObjectFile::toSymb(DataRefImpl Symb) const { + const coff_symbol *addr = reinterpret_cast<const coff_symbol*>(Symb.p); + +# ifndef NDEBUG + // Verify that the symbol points to a valid entry in the symbol table. + uintptr_t offset = uintptr_t(addr) - uintptr_t(base()); + if (offset < Header->PointerToSymbolTable + || offset >= Header->PointerToSymbolTable + + (Header->NumberOfSymbols * sizeof(coff_symbol))) + report_fatal_error("Symbol was outside of symbol table."); + + assert((offset - Header->PointerToSymbolTable) % sizeof(coff_symbol) + == 0 && "Symbol did not point to the beginning of a symbol"); +# endif + + return addr; +} + +const coff_section *COFFObjectFile::toSec(DataRefImpl Sec) const { + const coff_section *addr = reinterpret_cast<const coff_section*>(Sec.p); + +# ifndef NDEBUG + // Verify that the section points to a valid entry in the section table. + if (addr < SectionTable + || addr >= (SectionTable + Header->NumberOfSections)) + report_fatal_error("Section was outside of section table."); + + uintptr_t offset = uintptr_t(addr) - uintptr_t(SectionTable); + assert(offset % sizeof(coff_section) == 0 && + "Section did not point to the beginning of a section"); +# endif + + return addr; +} + +error_code COFFObjectFile::getSymbolNext(DataRefImpl Symb, + SymbolRef &Result) const { + const coff_symbol *symb = toSymb(Symb); + symb += 1 + symb->NumberOfAuxSymbols; + Symb.p = reinterpret_cast<uintptr_t>(symb); + Result = SymbolRef(Symb, this); + return object_error::success; +} + + error_code COFFObjectFile::getSymbolName(DataRefImpl Symb, + StringRef &Result) const { + const coff_symbol *symb = toSymb(Symb); + // Check for string table entry. First 4 bytes are 0. + if (symb->Name.Offset.Zeroes == 0) { + uint32_t Offset = symb->Name.Offset.Offset; + if (error_code ec = getString(Offset, Result)) + return ec; + return object_error::success; + } + + if (symb->Name.ShortName[7] == 0) + // Null terminated, let ::strlen figure out the length. + Result = StringRef(symb->Name.ShortName); + else + // Not null terminated, use all 8 bytes. + Result = StringRef(symb->Name.ShortName, 8); + return object_error::success; +} + +error_code COFFObjectFile::getSymbolAddress(DataRefImpl Symb, + uint64_t &Result) const { + const coff_symbol *symb = toSymb(Symb); + const coff_section *Section = NULL; + if (error_code ec = getSection(symb->SectionNumber, Section)) + return ec; + char Type; + if (error_code ec = getSymbolNMTypeChar(Symb, Type)) + return ec; + if (Type == 'U' || Type == 'w') + Result = UnknownAddressOrSize; + else if (Section) + Result = Section->VirtualAddress + symb->Value; + else + Result = symb->Value; + return object_error::success; +} + +error_code COFFObjectFile::getSymbolSize(DataRefImpl Symb, + uint64_t &Result) const { + // FIXME: Return the correct size. This requires looking at all the symbols + // in the same section as this symbol, and looking for either the next + // symbol, or the end of the section. + const coff_symbol *symb = toSymb(Symb); + const coff_section *Section = NULL; + if (error_code ec = getSection(symb->SectionNumber, Section)) + return ec; + char Type; + if (error_code ec = getSymbolNMTypeChar(Symb, Type)) + return ec; + if (Type == 'U' || Type == 'w') + Result = UnknownAddressOrSize; + else if (Section) + Result = Section->SizeOfRawData - symb->Value; + else + Result = 0; + return object_error::success; +} + +error_code COFFObjectFile::getSymbolNMTypeChar(DataRefImpl Symb, + char &Result) const { + const coff_symbol *symb = toSymb(Symb); + StringRef name; + if (error_code ec = getSymbolName(Symb, name)) + return ec; + char ret = StringSwitch<char>(name) + .StartsWith(".debug", 'N') + .StartsWith(".sxdata", 'N') + .Default('?'); + + if (ret != '?') { + Result = ret; + return object_error::success; + } + + uint32_t Characteristics = 0; + if (symb->SectionNumber > 0) { + const coff_section *Section = NULL; + if (error_code ec = getSection(symb->SectionNumber, Section)) + return ec; + Characteristics = Section->Characteristics; + } + + switch (symb->SectionNumber) { + case COFF::IMAGE_SYM_UNDEFINED: + // Check storage classes. + if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL) { + Result = 'w'; + return object_error::success; // Don't do ::toupper. + } else + ret = 'u'; + break; + case COFF::IMAGE_SYM_ABSOLUTE: + ret = 'a'; + break; + case COFF::IMAGE_SYM_DEBUG: + ret = 'n'; + break; + default: + // Check section type. + if (Characteristics & COFF::IMAGE_SCN_CNT_CODE) + ret = 't'; + else if ( Characteristics & COFF::IMAGE_SCN_MEM_READ + && ~Characteristics & COFF::IMAGE_SCN_MEM_WRITE) // Read only. + ret = 'r'; + else if (Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA) + ret = 'd'; + else if (Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA) + ret = 'b'; + else if (Characteristics & COFF::IMAGE_SCN_LNK_INFO) + ret = 'i'; + + // Check for section symbol. + else if ( symb->StorageClass == COFF::IMAGE_SYM_CLASS_STATIC + && symb->Value == 0) + ret = 's'; + } + + if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL) + ret = ::toupper(ret); + + Result = ret; + return object_error::success; +} + +error_code COFFObjectFile::isSymbolInternal(DataRefImpl Symb, + bool &Result) const { + Result = false; + return object_error::success; +} + +error_code COFFObjectFile::getSectionNext(DataRefImpl Sec, + SectionRef &Result) const { + const coff_section *sec = toSec(Sec); + sec += 1; + Sec.p = reinterpret_cast<uintptr_t>(sec); + Result = SectionRef(Sec, this); + return object_error::success; +} + +error_code COFFObjectFile::getSectionName(DataRefImpl Sec, + StringRef &Result) const { + const coff_section *sec = toSec(Sec); + StringRef name; + if (sec->Name[7] == 0) + // Null terminated, let ::strlen figure out the length. + name = sec->Name; + else + // Not null terminated, use all 8 bytes. + name = StringRef(sec->Name, 8); + + // Check for string table entry. First byte is '/'. + if (name[0] == '/') { + uint32_t Offset; + name.substr(1).getAsInteger(10, Offset); + if (error_code ec = getString(Offset, name)) + return ec; + } + + Result = name; + return object_error::success; +} + +error_code COFFObjectFile::getSectionAddress(DataRefImpl Sec, + uint64_t &Result) const { + const coff_section *sec = toSec(Sec); + Result = sec->VirtualAddress; + return object_error::success; +} + +error_code COFFObjectFile::getSectionSize(DataRefImpl Sec, + uint64_t &Result) const { + const coff_section *sec = toSec(Sec); + Result = sec->SizeOfRawData; + return object_error::success; +} + +error_code COFFObjectFile::getSectionContents(DataRefImpl Sec, + StringRef &Result) const { + const coff_section *sec = toSec(Sec); + // The only thing that we need to verify is that the contents is contained + // within the file bounds. We don't need to make sure it doesn't cover other + // data, as there's nothing that says that is not allowed. + uintptr_t con_start = uintptr_t(base()) + sec->PointerToRawData; + uintptr_t con_end = con_start + sec->SizeOfRawData; + if (con_end >= uintptr_t(Data->getBufferEnd())) + return object_error::parse_failed; + Result = StringRef(reinterpret_cast<const char*>(con_start), + sec->SizeOfRawData); + return object_error::success; +} + +error_code COFFObjectFile::isSectionText(DataRefImpl Sec, + bool &Result) const { + const coff_section *sec = toSec(Sec); + Result = sec->Characteristics & COFF::IMAGE_SCN_CNT_CODE; + return object_error::success; +} + +error_code COFFObjectFile::sectionContainsSymbol(DataRefImpl Sec, + DataRefImpl Symb, + bool &Result) const { + // FIXME: Unimplemented. + Result = false; + return object_error::success; +} + +COFFObjectFile::COFFObjectFile(MemoryBuffer *Object, error_code &ec) + : ObjectFile(Binary::isCOFF, Object, ec) { + // Check that we at least have enough room for a header. + if (!checkSize(Data, ec, sizeof(coff_file_header))) return; + + // The actual starting location of the COFF header in the file. This can be + // non-zero in PE/COFF files. + uint64_t HeaderStart = 0; + + // Check if this is a PE/COFF file. + if (base()[0] == 0x4d && base()[1] == 0x5a) { + // PE/COFF, seek through MS-DOS compatibility stub and 4-byte + // PE signature to find 'normal' COFF header. + if (!checkSize(Data, ec, 0x3c + 8)) return; + HeaderStart += *reinterpret_cast<const ulittle32_t *>(base() + 0x3c); + // Check the PE header. ("PE\0\0") + if (std::memcmp(base() + HeaderStart, "PE\0\0", 4) != 0) { + ec = object_error::parse_failed; + return; + } + HeaderStart += 4; // Skip the PE Header. + } + + Header = reinterpret_cast<const coff_file_header *>(base() + HeaderStart); + if (!checkAddr(Data, ec, uintptr_t(Header), sizeof(coff_file_header))) + return; + + SectionTable = + reinterpret_cast<const coff_section *>( base() + + HeaderStart + + sizeof(coff_file_header) + + Header->SizeOfOptionalHeader); + if (!checkAddr(Data, ec, uintptr_t(SectionTable), + Header->NumberOfSections * sizeof(coff_section))) + return; + + SymbolTable = + reinterpret_cast<const coff_symbol *>(base() + + Header->PointerToSymbolTable); + if (!checkAddr(Data, ec, uintptr_t(SymbolTable), + Header->NumberOfSymbols * sizeof(coff_symbol))) + return; + + // Find string table. + StringTable = reinterpret_cast<const char *>(base()) + + Header->PointerToSymbolTable + + Header->NumberOfSymbols * sizeof(coff_symbol); + if (!checkAddr(Data, ec, uintptr_t(StringTable), sizeof(ulittle32_t))) + return; + + StringTableSize = *reinterpret_cast<const ulittle32_t *>(StringTable); + if (!checkAddr(Data, ec, uintptr_t(StringTable), StringTableSize)) + return; + // Check that the string table is null terminated if has any in it. + if (StringTableSize < 4 + || (StringTableSize > 4 && StringTable[StringTableSize - 1] != 0)) { + ec = object_error::parse_failed; + return; + } + + ec = object_error::success; +} + +ObjectFile::symbol_iterator COFFObjectFile::begin_symbols() const { + DataRefImpl ret; + std::memset(&ret, 0, sizeof(DataRefImpl)); + ret.p = reinterpret_cast<intptr_t>(SymbolTable); + return symbol_iterator(SymbolRef(ret, this)); +} + +ObjectFile::symbol_iterator COFFObjectFile::end_symbols() const { + // The symbol table ends where the string table begins. + DataRefImpl ret; + std::memset(&ret, 0, sizeof(DataRefImpl)); + ret.p = reinterpret_cast<intptr_t>(StringTable); + return symbol_iterator(SymbolRef(ret, this)); +} + +ObjectFile::section_iterator COFFObjectFile::begin_sections() const { + DataRefImpl ret; + std::memset(&ret, 0, sizeof(DataRefImpl)); + ret.p = reinterpret_cast<intptr_t>(SectionTable); + return section_iterator(SectionRef(ret, this)); +} + +ObjectFile::section_iterator COFFObjectFile::end_sections() const { + DataRefImpl ret; + std::memset(&ret, 0, sizeof(DataRefImpl)); + ret.p = reinterpret_cast<intptr_t>(SectionTable + Header->NumberOfSections); + return section_iterator(SectionRef(ret, this)); +} + +uint8_t COFFObjectFile::getBytesInAddress() const { + return getArch() == Triple::x86_64 ? 8 : 4; +} + +StringRef COFFObjectFile::getFileFormatName() const { + switch(Header->Machine) { + case COFF::IMAGE_FILE_MACHINE_I386: + return "COFF-i386"; + case COFF::IMAGE_FILE_MACHINE_AMD64: + return "COFF-x86-64"; + default: + return "COFF-<unknown arch>"; + } +} + +unsigned COFFObjectFile::getArch() const { + switch(Header->Machine) { + case COFF::IMAGE_FILE_MACHINE_I386: + return Triple::x86; + case COFF::IMAGE_FILE_MACHINE_AMD64: + return Triple::x86_64; + default: + return Triple::UnknownArch; + } +} + +error_code COFFObjectFile::getSection(int32_t index, + const coff_section *&Result) const { + // Check for special index values. + if (index == COFF::IMAGE_SYM_UNDEFINED || + index == COFF::IMAGE_SYM_ABSOLUTE || + index == COFF::IMAGE_SYM_DEBUG) + Result = NULL; + else if (index > 0 && index <= Header->NumberOfSections) + // We already verified the section table data, so no need to check again. + Result = SectionTable + (index - 1); + else + return object_error::parse_failed; + return object_error::success; +} + +error_code COFFObjectFile::getString(uint32_t offset, + StringRef &Result) const { + if (StringTableSize <= 4) + // Tried to get a string from an empty string table. + return object_error::parse_failed; + if (offset >= StringTableSize) + return object_error::unexpected_eof; + Result = StringRef(StringTable + offset); + return object_error::success; +} + +namespace llvm { + + ObjectFile *ObjectFile::createCOFFObjectFile(MemoryBuffer *Object) { + error_code ec; + return new COFFObjectFile(Object, ec); + } + +} // end namespace llvm |
