1 //===-- ELFDump.cpp - ELF-specific dumper -----------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// This file implements the ELF-specific dumper for llvm-objdump.
13 //===----------------------------------------------------------------------===//
15 #include "llvm-objdump.h"
16 #include "llvm/Object/ELFObjectFile.h"
17 #include "llvm/Support/Format.h"
18 #include "llvm/Support/MathExtras.h"
19 #include "llvm/Support/raw_ostream.h"
22 using namespace llvm::object;
25 Expected<StringRef> getDynamicStrTab(const ELFFile<ELFT> *Elf) {
26 typedef ELFFile<ELFT> ELFO;
28 auto DynamicEntriesOrError = Elf->dynamicEntries();
29 if (!DynamicEntriesOrError)
30 return DynamicEntriesOrError.takeError();
32 for (const typename ELFO::Elf_Dyn &Dyn : *DynamicEntriesOrError) {
33 if (Dyn.d_tag == ELF::DT_STRTAB) {
34 auto MappedAddrOrError = Elf->toMappedAddr(Dyn.getPtr());
35 if (!MappedAddrOrError)
36 consumeError(MappedAddrOrError.takeError());
37 return StringRef(reinterpret_cast<const char *>(*MappedAddrOrError));
41 // If the dynamic segment is not present, we fall back on the sections.
42 auto SectionsOrError = Elf->sections();
44 return SectionsOrError.takeError();
46 for (const typename ELFO::Elf_Shdr &Sec : *SectionsOrError) {
47 if (Sec.sh_type == ELF::SHT_DYNSYM)
48 return Elf->getStringTableForSymtab(Sec);
51 return createError("dynamic string table not found");
55 void printDynamicSection(const ELFFile<ELFT> *Elf, StringRef Filename) {
56 auto ProgramHeaderOrError = Elf->program_headers();
57 if (!ProgramHeaderOrError)
58 report_error(Filename, ProgramHeaderOrError.takeError());
60 auto DynamicEntriesOrError = Elf->dynamicEntries();
61 if (!DynamicEntriesOrError)
62 report_error(Filename, DynamicEntriesOrError.takeError());
64 outs() << "Dynamic Section:\n";
65 for (const auto &Dyn : *DynamicEntriesOrError) {
66 if (Dyn.d_tag == ELF::DT_NULL)
69 StringRef Str = StringRef(Elf->getDynamicTagAsString(Dyn.d_tag));
72 std::string HexStr = utohexstr(static_cast<uint64_t>(Dyn.d_tag), true);
73 outs() << format(" 0x%-19s", HexStr.c_str());
75 // We use "-21" in order to match GNU objdump's output.
76 outs() << format(" %-21s", Str.data());
80 ELFT::Is64Bits ? "0x%016" PRIx64 "\n" : "0x%08" PRIx64 "\n";
81 if (Dyn.d_tag == ELF::DT_NEEDED) {
82 Expected<StringRef> StrTabOrErr = getDynamicStrTab(Elf);
84 const char *Data = StrTabOrErr.get().data();
85 outs() << (Data + Dyn.d_un.d_val) << "\n";
88 warn(errorToErrorCode(StrTabOrErr.takeError()).message());
89 consumeError(StrTabOrErr.takeError());
91 outs() << format(Fmt, (uint64_t)Dyn.d_un.d_val);
95 template <class ELFT> void printProgramHeaders(const ELFFile<ELFT> *o) {
96 typedef ELFFile<ELFT> ELFO;
97 outs() << "Program Header:\n";
98 auto ProgramHeaderOrError = o->program_headers();
99 if (!ProgramHeaderOrError)
101 errorToErrorCode(ProgramHeaderOrError.takeError()).message());
102 for (const typename ELFO::Elf_Phdr &Phdr : *ProgramHeaderOrError) {
103 switch (Phdr.p_type) {
104 case ELF::PT_DYNAMIC:
105 outs() << " DYNAMIC ";
107 case ELF::PT_GNU_EH_FRAME:
108 outs() << "EH_FRAME ";
110 case ELF::PT_GNU_RELRO:
113 case ELF::PT_GNU_STACK:
117 outs() << " INTERP ";
125 case ELF::PT_OPENBSD_BOOTDATA:
126 outs() << " OPENBSD_BOOTDATA ";
128 case ELF::PT_OPENBSD_RANDOMIZE:
129 outs() << " OPENBSD_RANDOMIZE ";
131 case ELF::PT_OPENBSD_WXNEEDED:
132 outs() << " OPENBSD_WXNEEDED ";
141 outs() << " UNKNOWN ";
144 const char *Fmt = ELFT::Is64Bits ? "0x%016" PRIx64 " " : "0x%08" PRIx64 " ";
146 outs() << "off " << format(Fmt, (uint64_t)Phdr.p_offset) << "vaddr "
147 << format(Fmt, (uint64_t)Phdr.p_vaddr) << "paddr "
148 << format(Fmt, (uint64_t)Phdr.p_paddr)
149 << format("align 2**%u\n",
150 countTrailingZeros<uint64_t>(Phdr.p_align))
151 << " filesz " << format(Fmt, (uint64_t)Phdr.p_filesz)
152 << "memsz " << format(Fmt, (uint64_t)Phdr.p_memsz) << "flags "
153 << ((Phdr.p_flags & ELF::PF_R) ? "r" : "-")
154 << ((Phdr.p_flags & ELF::PF_W) ? "w" : "-")
155 << ((Phdr.p_flags & ELF::PF_X) ? "x" : "-") << "\n";
160 void llvm::printELFFileHeader(const object::ObjectFile *Obj) {
161 // Little-endian 32-bit
162 if (const ELF32LEObjectFile *ELFObj = dyn_cast<ELF32LEObjectFile>(Obj))
163 printProgramHeaders(ELFObj->getELFFile());
166 if (const ELF32BEObjectFile *ELFObj = dyn_cast<ELF32BEObjectFile>(Obj))
167 printProgramHeaders(ELFObj->getELFFile());
169 // Little-endian 64-bit
170 if (const ELF64LEObjectFile *ELFObj = dyn_cast<ELF64LEObjectFile>(Obj))
171 printProgramHeaders(ELFObj->getELFFile());
174 if (const ELF64BEObjectFile *ELFObj = dyn_cast<ELF64BEObjectFile>(Obj))
175 printProgramHeaders(ELFObj->getELFFile());
178 void llvm::printELFDynamicSection(const object::ObjectFile *Obj) {
179 // Little-endian 32-bit
180 if (const ELF32LEObjectFile *ELFObj = dyn_cast<ELF32LEObjectFile>(Obj))
181 printDynamicSection(ELFObj->getELFFile(), Obj->getFileName());
184 if (const ELF32BEObjectFile *ELFObj = dyn_cast<ELF32BEObjectFile>(Obj))
185 printDynamicSection(ELFObj->getELFFile(), Obj->getFileName());
187 // Little-endian 64-bit
188 if (const ELF64LEObjectFile *ELFObj = dyn_cast<ELF64LEObjectFile>(Obj))
189 printDynamicSection(ELFObj->getELFFile(), Obj->getFileName());
192 if (const ELF64BEObjectFile *ELFObj = dyn_cast<ELF64BEObjectFile>(Obj))
193 printDynamicSection(ELFObj->getELFFile(), Obj->getFileName());