};
typedef content_iterator<ExportEntry> export_iterator;
+/// MachORebaseEntry encapsulates the current state in the decompression of
+/// rebasing opcodes. This allows you to iterate through the compressed table of
+/// rebasing using:
+/// for (const llvm::object::MachORebaseEntry &Entry : Obj->rebaseTable()) {
+/// }
+class MachORebaseEntry {
+public:
+ MachORebaseEntry(ArrayRef<uint8_t> opcodes, bool is64Bit);
+
+ uint32_t segmentIndex() const;
+ uint64_t segmentOffset() const;
+ StringRef typeName() const;
+
+ bool operator==(const MachORebaseEntry &) const;
+
+ void moveNext();
+
+private:
+ friend class MachOObjectFile;
+ void moveToFirst();
+ void moveToEnd();
+ uint64_t readULEB128();
+
+ ArrayRef<uint8_t> Opcodes;
+ const uint8_t *Ptr;
+ uint64_t SegmentOffset;
+ uint32_t SegmentIndex;
+ uint64_t RemainingLoopCount;
+ uint64_t AdvanceAmount;
+ uint8_t RebaseType;
+ uint8_t PointerSize;
+ bool Malformed;
+ bool Done;
+};
+typedef content_iterator<MachORebaseEntry> rebase_iterator;
+
class MachOObjectFile : public ObjectFile {
public:
struct LoadCommandInfo {
/// For use examining a trie not in a MachOObjectFile.
static iterator_range<export_iterator> exports(ArrayRef<uint8_t> Trie);
+ /// For use iterating over all rebase table entries.
+ iterator_range<rebase_iterator> rebaseTable() const;
+
+ /// For use examining rebase opcodes not in a MachOObjectFile.
+ static iterator_range<rebase_iterator> rebaseTable(ArrayRef<uint8_t> Opcodes,
+ bool is64);
+
// In a MachO file, sections have a segment name. This is used in the .o
// files. They have a single segment, but this field specifies which segment
// a section should be put in in the final object.
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Support/DataExtractor.h"
+#include "llvm/Support/Debug.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/LEB128.h"
}
+MachORebaseEntry::MachORebaseEntry(ArrayRef<uint8_t> Bytes, bool is64Bit)
+ : Opcodes(Bytes), Ptr(Bytes.begin()), SegmentOffset(0), SegmentIndex(0),
+ RemainingLoopCount(0), AdvanceAmount(0), RebaseType(0),
+ PointerSize(is64Bit ? 8 : 4), Malformed(false), Done(false) {}
+
+void MachORebaseEntry::moveToFirst() {
+ Ptr = Opcodes.begin();
+ moveNext();
+}
+
+void MachORebaseEntry::moveToEnd() {
+ Ptr = Opcodes.end();
+ RemainingLoopCount = 0;
+ Done = true;
+}
+
+void MachORebaseEntry::moveNext() {
+ // If in the middle of some loop, move to next rebasing in loop.
+ SegmentOffset += AdvanceAmount;
+ if (RemainingLoopCount) {
+ --RemainingLoopCount;
+ return;
+ }
+ if (Ptr == Opcodes.end()) {
+ Done = true;
+ return;
+ }
+ bool More = true;
+ while (More && !Malformed) {
+ // Parse next opcode and set up next loop.
+ uint8_t Byte = *Ptr++;
+ uint8_t ImmValue = Byte & MachO::REBASE_IMMEDIATE_MASK;
+ uint8_t Opcode = Byte & MachO::REBASE_OPCODE_MASK;
+ switch (Opcode) {
+ case MachO::REBASE_OPCODE_DONE:
+ More = false;
+ Done = true;
+ moveToEnd();
+ DEBUG_WITH_TYPE("mach-o-rebase", llvm::dbgs() << "REBASE_OPCODE_DONE\n");
+ break;
+ case MachO::REBASE_OPCODE_SET_TYPE_IMM:
+ RebaseType = ImmValue;
+ DEBUG_WITH_TYPE(
+ "mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_SET_TYPE_IMM: "
+ << "RebaseType=" << (int) RebaseType << "\n");
+ break;
+ case MachO::REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
+ SegmentIndex = ImmValue;
+ SegmentOffset = readULEB128();
+ DEBUG_WITH_TYPE(
+ "mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: "
+ << "SegmentIndex=" << SegmentIndex << ", "
+ << format("SegmentOffset=0x%06X", SegmentOffset)
+ << "\n");
+ break;
+ case MachO::REBASE_OPCODE_ADD_ADDR_ULEB:
+ SegmentOffset += readULEB128();
+ DEBUG_WITH_TYPE("mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_ADD_ADDR_ULEB: "
+ << format("SegmentOffset=0x%06X",
+ SegmentOffset) << "\n");
+ break;
+ case MachO::REBASE_OPCODE_ADD_ADDR_IMM_SCALED:
+ SegmentOffset += ImmValue * PointerSize;
+ DEBUG_WITH_TYPE("mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_ADD_ADDR_IMM_SCALED: "
+ << format("SegmentOffset=0x%06X",
+ SegmentOffset) << "\n");
+ break;
+ case MachO::REBASE_OPCODE_DO_REBASE_IMM_TIMES:
+ AdvanceAmount = PointerSize;
+ RemainingLoopCount = ImmValue - 1;
+ DEBUG_WITH_TYPE(
+ "mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_IMM_TIMES: "
+ << format("SegmentOffset=0x%06X", SegmentOffset)
+ << ", AdvanceAmount=" << AdvanceAmount
+ << ", RemainingLoopCount=" << RemainingLoopCount
+ << "\n");
+ return;
+ case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES:
+ AdvanceAmount = PointerSize;
+ RemainingLoopCount = readULEB128() - 1;
+ DEBUG_WITH_TYPE(
+ "mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES: "
+ << format("SegmentOffset=0x%06X", SegmentOffset)
+ << ", AdvanceAmount=" << AdvanceAmount
+ << ", RemainingLoopCount=" << RemainingLoopCount
+ << "\n");
+ return;
+ case MachO::REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB:
+ AdvanceAmount = readULEB128() + PointerSize;
+ RemainingLoopCount = 0;
+ DEBUG_WITH_TYPE(
+ "mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB: "
+ << format("SegmentOffset=0x%06X", SegmentOffset)
+ << ", AdvanceAmount=" << AdvanceAmount
+ << ", RemainingLoopCount=" << RemainingLoopCount
+ << "\n");
+ return;
+ case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB:
+ RemainingLoopCount = readULEB128() - 1;
+ AdvanceAmount = readULEB128() + PointerSize;
+ DEBUG_WITH_TYPE(
+ "mach-o-rebase",
+ llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB: "
+ << format("SegmentOffset=0x%06X", SegmentOffset)
+ << ", AdvanceAmount=" << AdvanceAmount
+ << ", RemainingLoopCount=" << RemainingLoopCount
+ << "\n");
+ return;
+ default:
+ Malformed = true;
+ }
+ }
+}
+
+uint64_t MachORebaseEntry::readULEB128() {
+ unsigned Count;
+ uint64_t Result = decodeULEB128(Ptr, &Count);
+ Ptr += Count;
+ if (Ptr > Opcodes.end()) {
+ Ptr = Opcodes.end();
+ Malformed = true;
+ }
+ return Result;
+}
+
+uint32_t MachORebaseEntry::segmentIndex() const { return SegmentIndex; }
+
+uint64_t MachORebaseEntry::segmentOffset() const { return SegmentOffset; }
+
+StringRef MachORebaseEntry::typeName() const {
+ switch (RebaseType) {
+ case MachO::REBASE_TYPE_POINTER:
+ return "pointer";
+ case MachO::REBASE_TYPE_TEXT_ABSOLUTE32:
+ return "text abs32";
+ case MachO::REBASE_TYPE_TEXT_PCREL32:
+ return "text rel32";
+ }
+ return "unknown";
+}
+
+bool MachORebaseEntry::operator==(const MachORebaseEntry &Other) const {
+ assert(Opcodes == Other.Opcodes && "compare iterators of different files");
+ return (Ptr == Other.Ptr) &&
+ (RemainingLoopCount == Other.RemainingLoopCount) &&
+ (Done == Other.Done);
+}
+
+iterator_range<rebase_iterator>
+MachOObjectFile::rebaseTable(ArrayRef<uint8_t> Opcodes, bool is64) {
+ MachORebaseEntry Start(Opcodes, is64);
+ Start.moveToFirst();
+
+ MachORebaseEntry Finish(Opcodes, is64);
+ Finish.moveToEnd();
+
+ return iterator_range<rebase_iterator>(rebase_iterator(Start),
+ rebase_iterator(Finish));
+}
+
+iterator_range<rebase_iterator> MachOObjectFile::rebaseTable() const {
+ return rebaseTable(getDyldInfoRebaseOpcodes(), is64Bit());
+}
+
StringRef
MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
--- /dev/null
+# RUN: llvm-objdump -macho -rebase -arch x86_64 \
+# RUN: %p/Inputs/rebase.macho-x86_64 2>/dev/null | FileCheck %s
+
+
+# CHECK: segment section address type
+# CHECK: __DATA __data 0x00001010 pointer
+# CHECK: __DATA __data 0x00001028 pointer
+# CHECK: __DATA __data 0x00001030 pointer
+# CHECK: __DATA __data 0x00001038 pointer
+# CHECK: __DATA __data 0x00001040 pointer
+# CHECK: __DATA __data 0x00001258 pointer
+# CHECK: __DATA __mystuff 0x00001278 pointer
+# CHECK: __DATA __mystuff 0x00001288 pointer
+# CHECK: __DATA __mystuff 0x00001298 pointer
+# CHECK: __DATA __mystuff 0x000012A8 pointer
outs() << "\n";
}
}
+
+
+//===----------------------------------------------------------------------===//
+// rebase table dumping
+//===----------------------------------------------------------------------===//
+
+namespace {
+class SegInfo {
+public:
+ SegInfo(const object::MachOObjectFile *Obj);
+
+ StringRef segmentName(uint32_t SegIndex);
+ StringRef sectionName(uint32_t SegIndex, uint64_t SegOffset);
+ uint64_t address(uint32_t SegIndex, uint64_t SegOffset);
+
+private:
+ struct SectionInfo {
+ uint64_t Address;
+ uint64_t Size;
+ StringRef SectionName;
+ StringRef SegmentName;
+ uint64_t OffsetInSegment;
+ uint64_t SegmentStartAddress;
+ uint32_t SegmentIndex;
+ };
+ const SectionInfo &findSection(uint32_t SegIndex, uint64_t SegOffset);
+ SmallVector<SectionInfo, 32> Sections;
+};
+}
+
+SegInfo::SegInfo(const object::MachOObjectFile *Obj) {
+ // Build table of sections so segIndex/offset pairs can be translated.
+ uint32_t CurSegIndex = 0;
+ StringRef CurSegName;
+ uint64_t CurSegAddress;
+ for (const SectionRef &Section : Obj->sections()) {
+ SectionInfo Info;
+ if (error(Section.getName(Info.SectionName)))
+ return;
+ if (error(Section.getAddress(Info.Address)))
+ return;
+ if (error(Section.getSize(Info.Size)))
+ return;
+ Info.SegmentName =
+ Obj->getSectionFinalSegmentName(Section.getRawDataRefImpl());
+ if (!Info.SegmentName.equals(CurSegName)) {
+ ++CurSegIndex;
+ CurSegName = Info.SegmentName;
+ CurSegAddress = Info.Address;
+ }
+ Info.SegmentIndex = CurSegIndex - 1;
+ Info.OffsetInSegment = Info.Address - CurSegAddress;
+ Info.SegmentStartAddress = CurSegAddress;
+ Sections.push_back(Info);
+ }
+}
+
+StringRef SegInfo::segmentName(uint32_t SegIndex) {
+ for (const SectionInfo &SI : Sections) {
+ if (SI.SegmentIndex == SegIndex)
+ return SI.SegmentName;
+ }
+ llvm_unreachable("invalid segIndex");
+}
+
+const SegInfo::SectionInfo &SegInfo::findSection(uint32_t SegIndex,
+ uint64_t OffsetInSeg) {
+ for (const SectionInfo &SI : Sections) {
+ if (SI.SegmentIndex != SegIndex)
+ continue;
+ if (SI.OffsetInSegment > OffsetInSeg)
+ continue;
+ if (OffsetInSeg >= (SI.OffsetInSegment + SI.Size))
+ continue;
+ return SI;
+ }
+ llvm_unreachable("segIndex and offset not in any section");
+}
+
+StringRef SegInfo::sectionName(uint32_t SegIndex, uint64_t OffsetInSeg) {
+ return findSection(SegIndex, OffsetInSeg).SectionName;
+}
+
+uint64_t SegInfo::address(uint32_t SegIndex, uint64_t OffsetInSeg) {
+ const SectionInfo &SI = findSection(SegIndex, OffsetInSeg);
+ return SI.SegmentStartAddress + OffsetInSeg;
+}
+
+void llvm::printMachORebaseTable(const object::MachOObjectFile *Obj) {
+ // Build table of sections so names can used in final output.
+ SegInfo sectionTable(Obj);
+
+ outs() << "segment section address type\n";
+ for (const llvm::object::MachORebaseEntry &Entry : Obj->rebaseTable()) {
+ uint32_t SegIndex = Entry.segmentIndex();
+ uint64_t OffsetInSeg = Entry.segmentOffset();
+ StringRef SegmentName = sectionTable.segmentName(SegIndex);
+ StringRef SectionName = sectionTable.sectionName(SegIndex, OffsetInSeg);
+ uint64_t Address = sectionTable.address(SegIndex, OffsetInSeg);
+
+ // Table lines look like: __DATA __nl_symbol_ptr 0x0000F00C pointer
+ outs() << format("%-8s %-18s 0x%08X %s\n", SegmentName.str().c_str(),
+ SectionName.str().c_str(), Address,
+ Entry.typeName().str().c_str());
+ }
+}
ExportsTrie("exports-trie", cl::desc("Display mach-o exported symbols"));
static cl::opt<bool>
+Rebase("rebase", cl::desc("Display mach-o rebasing info"));
+
+static cl::opt<bool>
MachOOpt("macho", cl::desc("Use MachO specific object file parser"));
static cl::alias
MachOm("m", cl::desc("Alias for --macho"), cl::aliasopt(MachOOpt));
}
}
+static void printRebaseTable(const ObjectFile *o) {
+ outs() << "Rebase table:\n";
+ if (const MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(o))
+ printMachORebaseTable(MachO);
+ else {
+ errs() << "This operation is only currently supported "
+ "for Mach-O executable files.\n";
+ return;
+ }
+}
+
+
static void printPrivateFileHeader(const ObjectFile *o) {
if (o->isELF()) {
printELFFileHeader(o);
printPrivateFileHeader(o);
if (ExportsTrie)
printExportsTrie(o);
+ if (Rebase)
+ printRebaseTable(o);
}
/// @brief Dump each object file in \a a;
&& !SymbolTable
&& !UnwindInfo
&& !PrivateHeaders
- && !ExportsTrie) {
+ && !ExportsTrie
+ && !Rebase) {
cl::PrintHelpMessage();
return 2;
}
void printCOFFUnwindInfo(const object::COFFObjectFile* o);
void printMachOUnwindInfo(const object::MachOObjectFile* o);
void printMachOExportsTrie(const object::MachOObjectFile* o);
+void printMachORebaseTable(const object::MachOObjectFile* o);
void printELFFileHeader(const object::ObjectFile *o);
void printCOFFFileHeader(const object::ObjectFile *o);
void printMachOFileHeader(const object::ObjectFile *o);