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Diffstat (limited to 'contrib/llvm/lib/Object/MachOObject.cpp')
| -rw-r--r-- | contrib/llvm/lib/Object/MachOObject.cpp | 422 |
1 files changed, 422 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Object/MachOObject.cpp b/contrib/llvm/lib/Object/MachOObject.cpp new file mode 100644 index 0000000..c9c341a --- /dev/null +++ b/contrib/llvm/lib/Object/MachOObject.cpp @@ -0,0 +1,422 @@ +//===- MachOObject.cpp - Mach-O Object File Wrapper -----------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Object/MachOObject.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/Support/DataExtractor.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/Host.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/SwapByteOrder.h" +#include "llvm/Support/raw_ostream.h" + +using namespace llvm; +using namespace llvm::object; + +/* Translation Utilities */ + +template<typename T> +static void SwapValue(T &Value) { + Value = sys::SwapByteOrder(Value); +} + +template<typename T> +static void SwapStruct(T &Value); + +template<typename T> +static void ReadInMemoryStruct(const MachOObject &MOO, + StringRef Buffer, uint64_t Base, + InMemoryStruct<T> &Res) { + typedef T struct_type; + uint64_t Size = sizeof(struct_type); + + // Check that the buffer contains the expected data. + if (Base + Size > Buffer.size()) { + Res = 0; + return; + } + + // Check whether we can return a direct pointer. + struct_type *Ptr = reinterpret_cast<struct_type *>( + const_cast<char *>(Buffer.data() + Base)); + if (!MOO.isSwappedEndian()) { + Res = Ptr; + return; + } + + // Otherwise, copy the struct and translate the values. + Res = *Ptr; + SwapStruct(*Res); +} + +/* *** */ + +MachOObject::MachOObject(MemoryBuffer *Buffer_, bool IsLittleEndian_, + bool Is64Bit_) + : Buffer(Buffer_), IsLittleEndian(IsLittleEndian_), Is64Bit(Is64Bit_), + IsSwappedEndian(IsLittleEndian != sys::isLittleEndianHost()), + HasStringTable(false), LoadCommands(0), NumLoadedCommands(0) { + // Load the common header. + memcpy(&Header, Buffer->getBuffer().data(), sizeof(Header)); + if (IsSwappedEndian) { + SwapValue(Header.Magic); + SwapValue(Header.CPUType); + SwapValue(Header.CPUSubtype); + SwapValue(Header.FileType); + SwapValue(Header.NumLoadCommands); + SwapValue(Header.SizeOfLoadCommands); + SwapValue(Header.Flags); + } + + if (is64Bit()) { + memcpy(&Header64Ext, Buffer->getBuffer().data() + sizeof(Header), + sizeof(Header64Ext)); + if (IsSwappedEndian) { + SwapValue(Header64Ext.Reserved); + } + } + + // Create the load command array if sane. + if (getHeader().NumLoadCommands < (1 << 20)) + LoadCommands = new LoadCommandInfo[getHeader().NumLoadCommands]; +} + +MachOObject::~MachOObject() { + delete [] LoadCommands; +} + +MachOObject *MachOObject::LoadFromBuffer(MemoryBuffer *Buffer, + std::string *ErrorStr) { + // First, check the magic value and initialize the basic object info. + bool IsLittleEndian = false, Is64Bit = false; + StringRef Magic = Buffer->getBuffer().slice(0, 4); + if (Magic == "\xFE\xED\xFA\xCE") { + } else if (Magic == "\xCE\xFA\xED\xFE") { + IsLittleEndian = true; + } else if (Magic == "\xFE\xED\xFA\xCF") { + Is64Bit = true; + } else if (Magic == "\xCF\xFA\xED\xFE") { + IsLittleEndian = true; + Is64Bit = true; + } else { + if (ErrorStr) *ErrorStr = "not a Mach object file (invalid magic)"; + return 0; + } + + // Ensure that the at least the full header is present. + unsigned HeaderSize = Is64Bit ? macho::Header64Size : macho::Header32Size; + if (Buffer->getBufferSize() < HeaderSize) { + if (ErrorStr) *ErrorStr = "not a Mach object file (invalid header)"; + return 0; + } + + OwningPtr<MachOObject> Object(new MachOObject(Buffer, IsLittleEndian, + Is64Bit)); + + // Check for bogus number of load commands. + if (Object->getHeader().NumLoadCommands >= (1 << 20)) { + if (ErrorStr) *ErrorStr = "not a Mach object file (unreasonable header)"; + return 0; + } + + if (ErrorStr) *ErrorStr = ""; + return Object.take(); +} + +StringRef MachOObject::getData(size_t Offset, size_t Size) const { + return Buffer->getBuffer().substr(Offset,Size); +} + +void MachOObject::RegisterStringTable(macho::SymtabLoadCommand &SLC) { + HasStringTable = true; + StringTable = Buffer->getBuffer().substr(SLC.StringTableOffset, + SLC.StringTableSize); +} + +const MachOObject::LoadCommandInfo & +MachOObject::getLoadCommandInfo(unsigned Index) const { + assert(Index < getHeader().NumLoadCommands && "Invalid index!"); + + // Load the command, if necessary. + if (Index >= NumLoadedCommands) { + uint64_t Offset; + if (Index == 0) { + Offset = getHeaderSize(); + } else { + const LoadCommandInfo &Prev = getLoadCommandInfo(Index - 1); + Offset = Prev.Offset + Prev.Command.Size; + } + + LoadCommandInfo &Info = LoadCommands[Index]; + memcpy(&Info.Command, Buffer->getBuffer().data() + Offset, + sizeof(macho::LoadCommand)); + if (IsSwappedEndian) { + SwapValue(Info.Command.Type); + SwapValue(Info.Command.Size); + } + Info.Offset = Offset; + NumLoadedCommands = Index + 1; + } + + return LoadCommands[Index]; +} + +template<> +void SwapStruct(macho::SegmentLoadCommand &Value) { + SwapValue(Value.Type); + SwapValue(Value.Size); + SwapValue(Value.VMAddress); + SwapValue(Value.VMSize); + SwapValue(Value.FileOffset); + SwapValue(Value.FileSize); + SwapValue(Value.MaxVMProtection); + SwapValue(Value.InitialVMProtection); + SwapValue(Value.NumSections); + SwapValue(Value.Flags); +} +void MachOObject::ReadSegmentLoadCommand(const LoadCommandInfo &LCI, + InMemoryStruct<macho::SegmentLoadCommand> &Res) const { + ReadInMemoryStruct(*this, Buffer->getBuffer(), LCI.Offset, Res); +} + +template<> +void SwapStruct(macho::Segment64LoadCommand &Value) { + SwapValue(Value.Type); + SwapValue(Value.Size); + SwapValue(Value.VMAddress); + SwapValue(Value.VMSize); + SwapValue(Value.FileOffset); + SwapValue(Value.FileSize); + SwapValue(Value.MaxVMProtection); + SwapValue(Value.InitialVMProtection); + SwapValue(Value.NumSections); + SwapValue(Value.Flags); +} +void MachOObject::ReadSegment64LoadCommand(const LoadCommandInfo &LCI, + InMemoryStruct<macho::Segment64LoadCommand> &Res) const { + ReadInMemoryStruct(*this, Buffer->getBuffer(), LCI.Offset, Res); +} + +template<> +void SwapStruct(macho::SymtabLoadCommand &Value) { + SwapValue(Value.Type); + SwapValue(Value.Size); + SwapValue(Value.SymbolTableOffset); + SwapValue(Value.NumSymbolTableEntries); + SwapValue(Value.StringTableOffset); + SwapValue(Value.StringTableSize); +} +void MachOObject::ReadSymtabLoadCommand(const LoadCommandInfo &LCI, + InMemoryStruct<macho::SymtabLoadCommand> &Res) const { + ReadInMemoryStruct(*this, Buffer->getBuffer(), LCI.Offset, Res); +} + +template<> +void SwapStruct(macho::DysymtabLoadCommand &Value) { + SwapValue(Value.Type); + SwapValue(Value.Size); + SwapValue(Value.LocalSymbolsIndex); + SwapValue(Value.NumLocalSymbols); + SwapValue(Value.ExternalSymbolsIndex); + SwapValue(Value.NumExternalSymbols); + SwapValue(Value.UndefinedSymbolsIndex); + SwapValue(Value.NumUndefinedSymbols); + SwapValue(Value.TOCOffset); + SwapValue(Value.NumTOCEntries); + SwapValue(Value.ModuleTableOffset); + SwapValue(Value.NumModuleTableEntries); + SwapValue(Value.ReferenceSymbolTableOffset); + SwapValue(Value.NumReferencedSymbolTableEntries); + SwapValue(Value.IndirectSymbolTableOffset); + SwapValue(Value.NumIndirectSymbolTableEntries); + SwapValue(Value.ExternalRelocationTableOffset); + SwapValue(Value.NumExternalRelocationTableEntries); + SwapValue(Value.LocalRelocationTableOffset); + SwapValue(Value.NumLocalRelocationTableEntries); +} +void MachOObject::ReadDysymtabLoadCommand(const LoadCommandInfo &LCI, + InMemoryStruct<macho::DysymtabLoadCommand> &Res) const { + ReadInMemoryStruct(*this, Buffer->getBuffer(), LCI.Offset, Res); +} + +template<> +void SwapStruct(macho::LinkeditDataLoadCommand &Value) { + SwapValue(Value.Type); + SwapValue(Value.Size); + SwapValue(Value.DataOffset); + SwapValue(Value.DataSize); +} +void MachOObject::ReadLinkeditDataLoadCommand(const LoadCommandInfo &LCI, + InMemoryStruct<macho::LinkeditDataLoadCommand> &Res) const { + ReadInMemoryStruct(*this, Buffer->getBuffer(), LCI.Offset, Res); +} + +template<> +void SwapStruct(macho::LinkerOptionsLoadCommand &Value) { + SwapValue(Value.Type); + SwapValue(Value.Size); + SwapValue(Value.Count); +} +void MachOObject::ReadLinkerOptionsLoadCommand(const LoadCommandInfo &LCI, + InMemoryStruct<macho::LinkerOptionsLoadCommand> &Res) const { + ReadInMemoryStruct(*this, Buffer->getBuffer(), LCI.Offset, Res); +} + +template<> +void SwapStruct(macho::IndirectSymbolTableEntry &Value) { + SwapValue(Value.Index); +} +void +MachOObject::ReadIndirectSymbolTableEntry(const macho::DysymtabLoadCommand &DLC, + unsigned Index, + InMemoryStruct<macho::IndirectSymbolTableEntry> &Res) const { + uint64_t Offset = (DLC.IndirectSymbolTableOffset + + Index * sizeof(macho::IndirectSymbolTableEntry)); + ReadInMemoryStruct(*this, Buffer->getBuffer(), Offset, Res); +} + + +template<> +void SwapStruct(macho::Section &Value) { + SwapValue(Value.Address); + SwapValue(Value.Size); + SwapValue(Value.Offset); + SwapValue(Value.Align); + SwapValue(Value.RelocationTableOffset); + SwapValue(Value.NumRelocationTableEntries); + SwapValue(Value.Flags); + SwapValue(Value.Reserved1); + SwapValue(Value.Reserved2); +} +void MachOObject::ReadSection(const LoadCommandInfo &LCI, + unsigned Index, + InMemoryStruct<macho::Section> &Res) const { + assert(LCI.Command.Type == macho::LCT_Segment && + "Unexpected load command info!"); + uint64_t Offset = (LCI.Offset + sizeof(macho::SegmentLoadCommand) + + Index * sizeof(macho::Section)); + ReadInMemoryStruct(*this, Buffer->getBuffer(), Offset, Res); +} + +template<> +void SwapStruct(macho::Section64 &Value) { + SwapValue(Value.Address); + SwapValue(Value.Size); + SwapValue(Value.Offset); + SwapValue(Value.Align); + SwapValue(Value.RelocationTableOffset); + SwapValue(Value.NumRelocationTableEntries); + SwapValue(Value.Flags); + SwapValue(Value.Reserved1); + SwapValue(Value.Reserved2); + SwapValue(Value.Reserved3); +} +void MachOObject::ReadSection64(const LoadCommandInfo &LCI, + unsigned Index, + InMemoryStruct<macho::Section64> &Res) const { + assert(LCI.Command.Type == macho::LCT_Segment64 && + "Unexpected load command info!"); + uint64_t Offset = (LCI.Offset + sizeof(macho::Segment64LoadCommand) + + Index * sizeof(macho::Section64)); + ReadInMemoryStruct(*this, Buffer->getBuffer(), Offset, Res); +} + +template<> +void SwapStruct(macho::RelocationEntry &Value) { + SwapValue(Value.Word0); + SwapValue(Value.Word1); +} +void MachOObject::ReadRelocationEntry(uint64_t RelocationTableOffset, + unsigned Index, + InMemoryStruct<macho::RelocationEntry> &Res) const { + uint64_t Offset = (RelocationTableOffset + + Index * sizeof(macho::RelocationEntry)); + ReadInMemoryStruct(*this, Buffer->getBuffer(), Offset, Res); +} + +template<> +void SwapStruct(macho::SymbolTableEntry &Value) { + SwapValue(Value.StringIndex); + SwapValue(Value.Flags); + SwapValue(Value.Value); +} +void MachOObject::ReadSymbolTableEntry(uint64_t SymbolTableOffset, + unsigned Index, + InMemoryStruct<macho::SymbolTableEntry> &Res) const { + uint64_t Offset = (SymbolTableOffset + + Index * sizeof(macho::SymbolTableEntry)); + ReadInMemoryStruct(*this, Buffer->getBuffer(), Offset, Res); +} + +template<> +void SwapStruct(macho::Symbol64TableEntry &Value) { + SwapValue(Value.StringIndex); + SwapValue(Value.Flags); + SwapValue(Value.Value); +} +void MachOObject::ReadSymbol64TableEntry(uint64_t SymbolTableOffset, + unsigned Index, + InMemoryStruct<macho::Symbol64TableEntry> &Res) const { + uint64_t Offset = (SymbolTableOffset + + Index * sizeof(macho::Symbol64TableEntry)); + ReadInMemoryStruct(*this, Buffer->getBuffer(), Offset, Res); +} + +template<> +void SwapStruct(macho::DataInCodeTableEntry &Value) { + SwapValue(Value.Offset); + SwapValue(Value.Length); + SwapValue(Value.Kind); +} +void MachOObject::ReadDataInCodeTableEntry(uint64_t TableOffset, + unsigned Index, + InMemoryStruct<macho::DataInCodeTableEntry> &Res) const { + uint64_t Offset = (TableOffset + + Index * sizeof(macho::DataInCodeTableEntry)); + ReadInMemoryStruct(*this, Buffer->getBuffer(), Offset, Res); +} + +void MachOObject::ReadULEB128s(uint64_t Index, + SmallVectorImpl<uint64_t> &Out) const { + DataExtractor extractor(Buffer->getBuffer(), true, 0); + + uint32_t offset = Index; + uint64_t data = 0; + while (uint64_t delta = extractor.getULEB128(&offset)) { + data += delta; + Out.push_back(data); + } +} + +/* ** */ +// Object Dumping Facilities +void MachOObject::dump() const { print(dbgs()); dbgs() << '\n'; } +void MachOObject::dumpHeader() const { printHeader(dbgs()); dbgs() << '\n'; } + +void MachOObject::printHeader(raw_ostream &O) const { + O << "('cputype', " << Header.CPUType << ")\n"; + O << "('cpusubtype', " << Header.CPUSubtype << ")\n"; + O << "('filetype', " << Header.FileType << ")\n"; + O << "('num_load_commands', " << Header.NumLoadCommands << ")\n"; + O << "('load_commands_size', " << Header.SizeOfLoadCommands << ")\n"; + O << "('flag', " << Header.Flags << ")\n"; + + // Print extended header if 64-bit. + if (is64Bit()) + O << "('reserved', " << Header64Ext.Reserved << ")\n"; +} + +void MachOObject::print(raw_ostream &O) const { + O << "Header:\n"; + printHeader(O); + O << "Load Commands:\n"; + + O << "Buffer:\n"; +} |
