1 //===- llvm-readobj.cpp - Dump contents of an Object File -----------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This is a tool similar to readelf, except it works on multiple object file
11 // formats. The main purpose of this tool is to provide detailed output suitable
12 // for FileCheck.
13 //
14 // Flags should be similar to readelf where supported, but the output format
15 // does not need to be identical. The point is to not make users learn yet
16 // another set of flags.
17 //
18 // Output should be specialized for each format where appropriate.
19 //
20 //===----------------------------------------------------------------------===//
21 
22 #include "llvm-readobj.h"
23 #include "Error.h"
24 #include "ObjDumper.h"
25 #include "llvm/DebugInfo/CodeView/TypeTableBuilder.h"
26 #include "llvm/Object/Archive.h"
27 #include "llvm/Object/COFFImportFile.h"
28 #include "llvm/Object/ELFObjectFile.h"
29 #include "llvm/Object/MachOUniversal.h"
30 #include "llvm/Object/ObjectFile.h"
31 #include "llvm/Support/Casting.h"
32 #include "llvm/Support/CommandLine.h"
33 #include "llvm/Support/DataTypes.h"
34 #include "llvm/Support/Debug.h"
35 #include "llvm/Support/FileSystem.h"
36 #include "llvm/Support/ManagedStatic.h"
37 #include "llvm/Support/PrettyStackTrace.h"
38 #include "llvm/Support/ScopedPrinter.h"
39 #include "llvm/Support/Signals.h"
40 #include "llvm/Support/TargetRegistry.h"
41 #include "llvm/Support/TargetSelect.h"
42 #include <string>
43 #include <system_error>
44 
45 using namespace llvm;
46 using namespace llvm::object;
47 
48 namespace opts {
49   cl::list<std::string> InputFilenames(cl::Positional,
50     cl::desc("<input object files>"),
51     cl::ZeroOrMore);
52 
53   // -file-headers, -h
54   cl::opt<bool> FileHeaders("file-headers",
55     cl::desc("Display file headers "));
56   cl::alias FileHeadersShort("h",
57     cl::desc("Alias for --file-headers"),
58     cl::aliasopt(FileHeaders));
59 
60   // -sections, -s
61   cl::opt<bool> Sections("sections",
62     cl::desc("Display all sections."));
63   cl::alias SectionsShort("s",
64     cl::desc("Alias for --sections"),
65     cl::aliasopt(Sections));
66 
67   // -section-relocations, -sr
68   cl::opt<bool> SectionRelocations("section-relocations",
69     cl::desc("Display relocations for each section shown."));
70   cl::alias SectionRelocationsShort("sr",
71     cl::desc("Alias for --section-relocations"),
72     cl::aliasopt(SectionRelocations));
73 
74   // -section-symbols, -st
75   cl::opt<bool> SectionSymbols("section-symbols",
76     cl::desc("Display symbols for each section shown."));
77   cl::alias SectionSymbolsShort("st",
78     cl::desc("Alias for --section-symbols"),
79     cl::aliasopt(SectionSymbols));
80 
81   // -section-data, -sd
82   cl::opt<bool> SectionData("section-data",
83     cl::desc("Display section data for each section shown."));
84   cl::alias SectionDataShort("sd",
85     cl::desc("Alias for --section-data"),
86     cl::aliasopt(SectionData));
87 
88   // -relocations, -r
89   cl::opt<bool> Relocations("relocations",
90     cl::desc("Display the relocation entries in the file"));
91   cl::alias RelocationsShort("r",
92     cl::desc("Alias for --relocations"),
93     cl::aliasopt(Relocations));
94 
95   // -notes, -n
96   cl::opt<bool> Notes("notes", cl::desc("Display the ELF notes in the file"));
97   cl::alias NotesShort("n", cl::desc("Alias for --notes"), cl::aliasopt(Notes));
98 
99   // -dyn-relocations
100   cl::opt<bool> DynRelocs("dyn-relocations",
101     cl::desc("Display the dynamic relocation entries in the file"));
102 
103   // -symbols, -t
104   cl::opt<bool> Symbols("symbols",
105     cl::desc("Display the symbol table"));
106   cl::alias SymbolsShort("t",
107     cl::desc("Alias for --symbols"),
108     cl::aliasopt(Symbols));
109 
110   // -dyn-symbols, -dt
111   cl::opt<bool> DynamicSymbols("dyn-symbols",
112     cl::desc("Display the dynamic symbol table"));
113   cl::alias DynamicSymbolsShort("dt",
114     cl::desc("Alias for --dyn-symbols"),
115     cl::aliasopt(DynamicSymbols));
116 
117   // -unwind, -u
118   cl::opt<bool> UnwindInfo("unwind",
119     cl::desc("Display unwind information"));
120   cl::alias UnwindInfoShort("u",
121     cl::desc("Alias for --unwind"),
122     cl::aliasopt(UnwindInfo));
123 
124   // -dynamic-table
125   cl::opt<bool> DynamicTable("dynamic-table",
126     cl::desc("Display the ELF .dynamic section table"));
127   cl::alias DynamicTableShort("d", cl::desc("Alias for --dynamic-table"),
128                               cl::aliasopt(DynamicTable));
129 
130   // -needed-libs
131   cl::opt<bool> NeededLibraries("needed-libs",
132     cl::desc("Display the needed libraries"));
133 
134   // -program-headers
135   cl::opt<bool> ProgramHeaders("program-headers",
136     cl::desc("Display ELF program headers"));
137   cl::alias ProgramHeadersShort("l", cl::desc("Alias for --program-headers"),
138                                 cl::aliasopt(ProgramHeaders));
139 
140   // -hash-table
141   cl::opt<bool> HashTable("hash-table",
142     cl::desc("Display ELF hash table"));
143 
144   // -gnu-hash-table
145   cl::opt<bool> GnuHashTable("gnu-hash-table",
146     cl::desc("Display ELF .gnu.hash section"));
147 
148   // -expand-relocs
149   cl::opt<bool> ExpandRelocs("expand-relocs",
150     cl::desc("Expand each shown relocation to multiple lines"));
151 
152   // -codeview
153   cl::opt<bool> CodeView("codeview",
154                          cl::desc("Display CodeView debug information"));
155 
156   // -codeview-merged-types
157   cl::opt<bool>
158       CodeViewMergedTypes("codeview-merged-types",
159                           cl::desc("Display the merged CodeView type stream"));
160 
161   // -codeview-subsection-bytes
162   cl::opt<bool> CodeViewSubsectionBytes(
163       "codeview-subsection-bytes",
164       cl::desc("Dump raw contents of codeview debug sections and records"));
165 
166   // -arm-attributes, -a
167   cl::opt<bool> ARMAttributes("arm-attributes",
168                               cl::desc("Display the ARM attributes section"));
169   cl::alias ARMAttributesShort("a", cl::desc("Alias for --arm-attributes"),
170                                cl::aliasopt(ARMAttributes));
171 
172   // -mips-plt-got
173   cl::opt<bool>
174   MipsPLTGOT("mips-plt-got",
175              cl::desc("Display the MIPS GOT and PLT GOT sections"));
176 
177   // -mips-abi-flags
178   cl::opt<bool> MipsABIFlags("mips-abi-flags",
179                              cl::desc("Display the MIPS.abiflags section"));
180 
181   // -mips-reginfo
182   cl::opt<bool> MipsReginfo("mips-reginfo",
183                             cl::desc("Display the MIPS .reginfo section"));
184 
185   // -mips-options
186   cl::opt<bool> MipsOptions("mips-options",
187                             cl::desc("Display the MIPS .MIPS.options section"));
188 
189   // -amdgpu-code-object-metadata
190   cl::opt<bool> AMDGPUCodeObjectMetadata(
191       "amdgpu-code-object-metadata",
192       cl::desc("Display AMDGPU code object metadata"));
193 
194   // -coff-imports
195   cl::opt<bool>
196   COFFImports("coff-imports", cl::desc("Display the PE/COFF import table"));
197 
198   // -coff-exports
199   cl::opt<bool>
200   COFFExports("coff-exports", cl::desc("Display the PE/COFF export table"));
201 
202   // -coff-directives
203   cl::opt<bool>
204   COFFDirectives("coff-directives",
205                  cl::desc("Display the PE/COFF .drectve section"));
206 
207   // -coff-basereloc
208   cl::opt<bool>
209   COFFBaseRelocs("coff-basereloc",
210                  cl::desc("Display the PE/COFF .reloc section"));
211 
212   // -coff-debug-directory
213   cl::opt<bool>
214   COFFDebugDirectory("coff-debug-directory",
215                      cl::desc("Display the PE/COFF debug directory"));
216 
217   // -coff-resources
218   cl::opt<bool> COFFResources("coff-resources",
219                               cl::desc("Display the PE/COFF .rsrc section"));
220 
221   // -macho-data-in-code
222   cl::opt<bool>
223   MachODataInCode("macho-data-in-code",
224                   cl::desc("Display MachO Data in Code command"));
225 
226   // -macho-indirect-symbols
227   cl::opt<bool>
228   MachOIndirectSymbols("macho-indirect-symbols",
229                   cl::desc("Display MachO indirect symbols"));
230 
231   // -macho-linker-options
232   cl::opt<bool>
233   MachOLinkerOptions("macho-linker-options",
234                   cl::desc("Display MachO linker options"));
235 
236   // -macho-segment
237   cl::opt<bool>
238   MachOSegment("macho-segment",
239                   cl::desc("Display MachO Segment command"));
240 
241   // -macho-version-min
242   cl::opt<bool>
243   MachOVersionMin("macho-version-min",
244                   cl::desc("Display MachO version min command"));
245 
246   // -macho-dysymtab
247   cl::opt<bool>
248   MachODysymtab("macho-dysymtab",
249                   cl::desc("Display MachO Dysymtab command"));
250 
251   // -stackmap
252   cl::opt<bool>
253   PrintStackMap("stackmap",
254                 cl::desc("Display contents of stackmap section"));
255 
256   // -version-info
257   cl::opt<bool>
258       VersionInfo("version-info",
259                   cl::desc("Display ELF version sections (if present)"));
260   cl::alias VersionInfoShort("V", cl::desc("Alias for -version-info"),
261                              cl::aliasopt(VersionInfo));
262 
263   cl::opt<bool> SectionGroups("elf-section-groups",
264                               cl::desc("Display ELF section group contents"));
265   cl::alias SectionGroupsShort("g", cl::desc("Alias for -elf-sections-groups"),
266                                cl::aliasopt(SectionGroups));
267   cl::opt<bool> HashHistogram(
268       "elf-hash-histogram",
269       cl::desc("Display bucket list histogram for hash sections"));
270   cl::alias HashHistogramShort("I", cl::desc("Alias for -elf-hash-histogram"),
271                                cl::aliasopt(HashHistogram));
272 
273   cl::opt<OutputStyleTy>
274       Output("elf-output-style", cl::desc("Specify ELF dump style"),
275              cl::values(clEnumVal(LLVM, "LLVM default style"),
276                         clEnumVal(GNU, "GNU readelf style")),
277              cl::init(LLVM));
278 } // namespace opts
279 
280 namespace llvm {
281 
282 LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg) {
283   errs() << "\nError reading file: " << Msg << ".\n";
284   errs().flush();
285   exit(1);
286 }
287 
288 void error(Error EC) {
289   if (!EC)
290     return;
291   handleAllErrors(std::move(EC),
292                   [&](const ErrorInfoBase &EI) { reportError(EI.message()); });
293 }
294 
295 void error(std::error_code EC) {
296   if (!EC)
297     return;
298   reportError(EC.message());
299 }
300 
301 bool relocAddressLess(RelocationRef a, RelocationRef b) {
302   return a.getOffset() < b.getOffset();
303 }
304 
305 } // namespace llvm
306 
307 static void reportError(StringRef Input, std::error_code EC) {
308   if (Input == "-")
309     Input = "<stdin>";
310 
311   reportError(Twine(Input) + ": " + EC.message());
312 }
313 
314 static void reportError(StringRef Input, Error Err) {
315   if (Input == "-")
316     Input = "<stdin>";
317   std::string ErrMsg;
318   {
319     raw_string_ostream ErrStream(ErrMsg);
320     logAllUnhandledErrors(std::move(Err), ErrStream, Input + ": ");
321   }
322   reportError(ErrMsg);
323 }
324 
325 static bool isMipsArch(unsigned Arch) {
326   switch (Arch) {
327   case llvm::Triple::mips:
328   case llvm::Triple::mipsel:
329   case llvm::Triple::mips64:
330   case llvm::Triple::mips64el:
331     return true;
332   default:
333     return false;
334   }
335 }
336 namespace {
337 struct ReadObjTypeTableBuilder {
338   ReadObjTypeTableBuilder()
339       : Allocator(), IDTable(Allocator), TypeTable(Allocator) {}
340 
341   llvm::BumpPtrAllocator Allocator;
342   llvm::codeview::TypeTableBuilder IDTable;
343   llvm::codeview::TypeTableBuilder TypeTable;
344 };
345 }
346 static ReadObjTypeTableBuilder CVTypes;
347 
348 /// @brief Creates an format-specific object file dumper.
349 static std::error_code createDumper(const ObjectFile *Obj,
350                                     ScopedPrinter &Writer,
351                                     std::unique_ptr<ObjDumper> &Result) {
352   if (!Obj)
353     return readobj_error::unsupported_file_format;
354 
355   if (Obj->isCOFF())
356     return createCOFFDumper(Obj, Writer, Result);
357   if (Obj->isELF())
358     return createELFDumper(Obj, Writer, Result);
359   if (Obj->isMachO())
360     return createMachODumper(Obj, Writer, Result);
361   if (Obj->isWasm())
362     return createWasmDumper(Obj, Writer, Result);
363 
364   return readobj_error::unsupported_obj_file_format;
365 }
366 
367 /// @brief Dumps the specified object file.
368 static void dumpObject(const ObjectFile *Obj) {
369   ScopedPrinter Writer(outs());
370   std::unique_ptr<ObjDumper> Dumper;
371   if (std::error_code EC = createDumper(Obj, Writer, Dumper))
372     reportError(Obj->getFileName(), EC);
373 
374   if (opts::Output == opts::LLVM) {
375     outs() << '\n';
376     outs() << "File: " << Obj->getFileName() << "\n";
377     outs() << "Format: " << Obj->getFileFormatName() << "\n";
378     outs() << "Arch: " << Triple::getArchTypeName(
379                               (llvm::Triple::ArchType)Obj->getArch()) << "\n";
380     outs() << "AddressSize: " << (8 * Obj->getBytesInAddress()) << "bit\n";
381     Dumper->printLoadName();
382   }
383 
384   if (opts::FileHeaders)
385     Dumper->printFileHeaders();
386   if (opts::Sections)
387     Dumper->printSections();
388   if (opts::Relocations)
389     Dumper->printRelocations();
390   if (opts::DynRelocs)
391     Dumper->printDynamicRelocations();
392   if (opts::Symbols)
393     Dumper->printSymbols();
394   if (opts::DynamicSymbols)
395     Dumper->printDynamicSymbols();
396   if (opts::UnwindInfo)
397     Dumper->printUnwindInfo();
398   if (opts::DynamicTable)
399     Dumper->printDynamicTable();
400   if (opts::NeededLibraries)
401     Dumper->printNeededLibraries();
402   if (opts::ProgramHeaders)
403     Dumper->printProgramHeaders();
404   if (opts::HashTable)
405     Dumper->printHashTable();
406   if (opts::GnuHashTable)
407     Dumper->printGnuHashTable();
408   if (opts::VersionInfo)
409     Dumper->printVersionInfo();
410   if (Obj->isELF()) {
411     if (Obj->getArch() == llvm::Triple::arm)
412       if (opts::ARMAttributes)
413         Dumper->printAttributes();
414     if (isMipsArch(Obj->getArch())) {
415       if (opts::MipsPLTGOT)
416         Dumper->printMipsPLTGOT();
417       if (opts::MipsABIFlags)
418         Dumper->printMipsABIFlags();
419       if (opts::MipsReginfo)
420         Dumper->printMipsReginfo();
421       if (opts::MipsOptions)
422         Dumper->printMipsOptions();
423     }
424     if (Obj->getArch() == llvm::Triple::amdgcn)
425       if (opts::AMDGPUCodeObjectMetadata)
426         Dumper->printAMDGPUCodeObjectMetadata();
427     if (opts::SectionGroups)
428       Dumper->printGroupSections();
429     if (opts::HashHistogram)
430       Dumper->printHashHistogram();
431     if (opts::Notes)
432       Dumper->printNotes();
433   }
434   if (Obj->isCOFF()) {
435     if (opts::COFFImports)
436       Dumper->printCOFFImports();
437     if (opts::COFFExports)
438       Dumper->printCOFFExports();
439     if (opts::COFFDirectives)
440       Dumper->printCOFFDirectives();
441     if (opts::COFFBaseRelocs)
442       Dumper->printCOFFBaseReloc();
443     if (opts::COFFDebugDirectory)
444       Dumper->printCOFFDebugDirectory();
445     if (opts::COFFResources)
446       Dumper->printCOFFResources();
447     if (opts::CodeView)
448       Dumper->printCodeViewDebugInfo();
449     if (opts::CodeViewMergedTypes)
450       Dumper->mergeCodeViewTypes(CVTypes.IDTable, CVTypes.TypeTable);
451   }
452   if (Obj->isMachO()) {
453     if (opts::MachODataInCode)
454       Dumper->printMachODataInCode();
455     if (opts::MachOIndirectSymbols)
456       Dumper->printMachOIndirectSymbols();
457     if (opts::MachOLinkerOptions)
458       Dumper->printMachOLinkerOptions();
459     if (opts::MachOSegment)
460       Dumper->printMachOSegment();
461     if (opts::MachOVersionMin)
462       Dumper->printMachOVersionMin();
463     if (opts::MachODysymtab)
464       Dumper->printMachODysymtab();
465   }
466   if (opts::PrintStackMap)
467     Dumper->printStackMap();
468 }
469 
470 /// @brief Dumps each object file in \a Arc;
471 static void dumpArchive(const Archive *Arc) {
472   Error Err = Error::success();
473   for (auto &Child : Arc->children(Err)) {
474     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
475     if (!ChildOrErr) {
476       if (auto E = isNotObjectErrorInvalidFileType(ChildOrErr.takeError())) {
477         reportError(Arc->getFileName(), ChildOrErr.takeError());
478       }
479       continue;
480     }
481     if (ObjectFile *Obj = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
482       dumpObject(Obj);
483     else if (COFFImportFile *Imp = dyn_cast<COFFImportFile>(&*ChildOrErr.get()))
484       dumpCOFFImportFile(Imp);
485     else
486       reportError(Arc->getFileName(), readobj_error::unrecognized_file_format);
487   }
488   if (Err)
489     reportError(Arc->getFileName(), std::move(Err));
490 }
491 
492 /// @brief Dumps each object file in \a MachO Universal Binary;
493 static void dumpMachOUniversalBinary(const MachOUniversalBinary *UBinary) {
494   for (const MachOUniversalBinary::ObjectForArch &Obj : UBinary->objects()) {
495     Expected<std::unique_ptr<MachOObjectFile>> ObjOrErr = Obj.getAsObjectFile();
496     if (ObjOrErr)
497       dumpObject(&*ObjOrErr.get());
498     else if (auto E = isNotObjectErrorInvalidFileType(ObjOrErr.takeError())) {
499       reportError(UBinary->getFileName(), ObjOrErr.takeError());
500     }
501     else if (Expected<std::unique_ptr<Archive>> AOrErr = Obj.getAsArchive())
502       dumpArchive(&*AOrErr.get());
503   }
504 }
505 
506 /// @brief Opens \a File and dumps it.
507 static void dumpInput(StringRef File) {
508 
509   // Attempt to open the binary.
510   Expected<OwningBinary<Binary>> BinaryOrErr = createBinary(File);
511   if (!BinaryOrErr)
512     reportError(File, BinaryOrErr.takeError());
513   Binary &Binary = *BinaryOrErr.get().getBinary();
514 
515   if (Archive *Arc = dyn_cast<Archive>(&Binary))
516     dumpArchive(Arc);
517   else if (MachOUniversalBinary *UBinary =
518                dyn_cast<MachOUniversalBinary>(&Binary))
519     dumpMachOUniversalBinary(UBinary);
520   else if (ObjectFile *Obj = dyn_cast<ObjectFile>(&Binary))
521     dumpObject(Obj);
522   else if (COFFImportFile *Import = dyn_cast<COFFImportFile>(&Binary))
523     dumpCOFFImportFile(Import);
524   else
525     reportError(File, readobj_error::unrecognized_file_format);
526 }
527 
528 int main(int argc, const char *argv[]) {
529   sys::PrintStackTraceOnErrorSignal(argv[0]);
530   PrettyStackTraceProgram X(argc, argv);
531   llvm_shutdown_obj Y;
532 
533   // Register the target printer for --version.
534   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
535 
536   cl::ParseCommandLineOptions(argc, argv, "LLVM Object Reader\n");
537 
538   // Default to stdin if no filename is specified.
539   if (opts::InputFilenames.size() == 0)
540     opts::InputFilenames.push_back("-");
541 
542   std::for_each(opts::InputFilenames.begin(), opts::InputFilenames.end(),
543                 dumpInput);
544 
545   if (opts::CodeViewMergedTypes) {
546     ScopedPrinter W(outs());
547     dumpCodeViewMergedTypes(W, CVTypes.IDTable, CVTypes.TypeTable);
548   }
549 
550   return 0;
551 }
552