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/MemoryTypeTableBuilder.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   // -dyn-relocations
96   cl::opt<bool> DynRelocs("dyn-relocations",
97     cl::desc("Display the dynamic relocation entries in the file"));
98 
99   // -symbols, -t
100   cl::opt<bool> Symbols("symbols",
101     cl::desc("Display the symbol table"));
102   cl::alias SymbolsShort("t",
103     cl::desc("Alias for --symbols"),
104     cl::aliasopt(Symbols));
105 
106   // -dyn-symbols, -dt
107   cl::opt<bool> DynamicSymbols("dyn-symbols",
108     cl::desc("Display the dynamic symbol table"));
109   cl::alias DynamicSymbolsShort("dt",
110     cl::desc("Alias for --dyn-symbols"),
111     cl::aliasopt(DynamicSymbols));
112 
113   // -unwind, -u
114   cl::opt<bool> UnwindInfo("unwind",
115     cl::desc("Display unwind information"));
116   cl::alias UnwindInfoShort("u",
117     cl::desc("Alias for --unwind"),
118     cl::aliasopt(UnwindInfo));
119 
120   // -dynamic-table
121   cl::opt<bool> DynamicTable("dynamic-table",
122     cl::desc("Display the ELF .dynamic section table"));
123 
124   // -needed-libs
125   cl::opt<bool> NeededLibraries("needed-libs",
126     cl::desc("Display the needed libraries"));
127 
128   // -program-headers
129   cl::opt<bool> ProgramHeaders("program-headers",
130     cl::desc("Display ELF program headers"));
131 
132   // -hash-table
133   cl::opt<bool> HashTable("hash-table",
134     cl::desc("Display ELF hash table"));
135 
136   // -gnu-hash-table
137   cl::opt<bool> GnuHashTable("gnu-hash-table",
138     cl::desc("Display ELF .gnu.hash section"));
139 
140   // -expand-relocs
141   cl::opt<bool> ExpandRelocs("expand-relocs",
142     cl::desc("Expand each shown relocation to multiple lines"));
143 
144   // -codeview
145   cl::opt<bool> CodeView("codeview",
146                          cl::desc("Display CodeView debug information"));
147 
148   // -codeview-merged-types
149   cl::opt<bool>
150       CodeViewMergedTypes("codeview-merged-types",
151                           cl::desc("Display the merged CodeView type stream"));
152 
153   // -codeview-subsection-bytes
154   cl::opt<bool> CodeViewSubsectionBytes(
155       "codeview-subsection-bytes",
156       cl::desc("Dump raw contents of codeview debug sections and records"));
157 
158   // -arm-attributes, -a
159   cl::opt<bool> ARMAttributes("arm-attributes",
160                               cl::desc("Display the ARM attributes section"));
161   cl::alias ARMAttributesShort("-a", cl::desc("Alias for --arm-attributes"),
162                                cl::aliasopt(ARMAttributes));
163 
164   // -mips-plt-got
165   cl::opt<bool>
166   MipsPLTGOT("mips-plt-got",
167              cl::desc("Display the MIPS GOT and PLT GOT sections"));
168 
169   // -mips-abi-flags
170   cl::opt<bool> MipsABIFlags("mips-abi-flags",
171                              cl::desc("Display the MIPS.abiflags section"));
172 
173   // -mips-reginfo
174   cl::opt<bool> MipsReginfo("mips-reginfo",
175                             cl::desc("Display the MIPS .reginfo section"));
176 
177   // -mips-options
178   cl::opt<bool> MipsOptions("mips-options",
179                             cl::desc("Display the MIPS .MIPS.options section"));
180 
181   // -coff-imports
182   cl::opt<bool>
183   COFFImports("coff-imports", cl::desc("Display the PE/COFF import table"));
184 
185   // -coff-exports
186   cl::opt<bool>
187   COFFExports("coff-exports", cl::desc("Display the PE/COFF export table"));
188 
189   // -coff-directives
190   cl::opt<bool>
191   COFFDirectives("coff-directives",
192                  cl::desc("Display the PE/COFF .drectve section"));
193 
194   // -coff-basereloc
195   cl::opt<bool>
196   COFFBaseRelocs("coff-basereloc",
197                  cl::desc("Display the PE/COFF .reloc section"));
198 
199   // -macho-data-in-code
200   cl::opt<bool>
201   MachODataInCode("macho-data-in-code",
202                   cl::desc("Display MachO Data in Code command"));
203 
204   // -macho-indirect-symbols
205   cl::opt<bool>
206   MachOIndirectSymbols("macho-indirect-symbols",
207                   cl::desc("Display MachO indirect symbols"));
208 
209   // -macho-linker-options
210   cl::opt<bool>
211   MachOLinkerOptions("macho-linker-options",
212                   cl::desc("Display MachO linker options"));
213 
214   // -macho-segment
215   cl::opt<bool>
216   MachOSegment("macho-segment",
217                   cl::desc("Display MachO Segment command"));
218 
219   // -macho-version-min
220   cl::opt<bool>
221   MachOVersionMin("macho-version-min",
222                   cl::desc("Display MachO version min command"));
223 
224   // -macho-dysymtab
225   cl::opt<bool>
226   MachODysymtab("macho-dysymtab",
227                   cl::desc("Display MachO Dysymtab command"));
228 
229   // -stackmap
230   cl::opt<bool>
231   PrintStackMap("stackmap",
232                 cl::desc("Display contents of stackmap section"));
233 
234   // -version-info
235   cl::opt<bool>
236       VersionInfo("version-info",
237                   cl::desc("Display ELF version sections (if present)"));
238   cl::alias VersionInfoShort("V", cl::desc("Alias for -version-info"),
239                              cl::aliasopt(VersionInfo));
240 
241   cl::opt<bool> SectionGroups("elf-section-groups",
242                               cl::desc("Display ELF section group contents"));
243   cl::alias SectionGroupsShort("g", cl::desc("Alias for -elf-sections-groups"),
244                                cl::aliasopt(SectionGroups));
245   cl::opt<bool> HashHistogram(
246       "elf-hash-histogram",
247       cl::desc("Display bucket list histogram for hash sections"));
248   cl::alias HashHistogramShort("I", cl::desc("Alias for -elf-hash-histogram"),
249                                cl::aliasopt(HashHistogram));
250 
251   cl::opt<OutputStyleTy>
252       Output("elf-output-style", cl::desc("Specify ELF dump style"),
253              cl::values(clEnumVal(LLVM, "LLVM default style"),
254                         clEnumVal(GNU, "GNU readelf style"), clEnumValEnd),
255              cl::init(LLVM));
256 } // namespace opts
257 
258 namespace llvm {
259 
260 LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg) {
261   errs() << "\nError reading file: " << Msg << ".\n";
262   errs().flush();
263   exit(1);
264 }
265 
266 void error(std::error_code EC) {
267   if (!EC)
268     return;
269 
270   reportError(EC.message());
271 }
272 
273 bool relocAddressLess(RelocationRef a, RelocationRef b) {
274   return a.getOffset() < b.getOffset();
275 }
276 
277 } // namespace llvm
278 
279 static void reportError(StringRef Input, std::error_code EC) {
280   if (Input == "-")
281     Input = "<stdin>";
282 
283   reportError(Twine(Input) + ": " + EC.message());
284 }
285 
286 static void reportError(StringRef Input, StringRef Message) {
287   if (Input == "-")
288     Input = "<stdin>";
289 
290   reportError(Twine(Input) + ": " + Message);
291 }
292 
293 static bool isMipsArch(unsigned Arch) {
294   switch (Arch) {
295   case llvm::Triple::mips:
296   case llvm::Triple::mipsel:
297   case llvm::Triple::mips64:
298   case llvm::Triple::mips64el:
299     return true;
300   default:
301     return false;
302   }
303 }
304 
305 static llvm::codeview::MemoryTypeTableBuilder CVTypes;
306 
307 /// @brief Creates an format-specific object file dumper.
308 static std::error_code createDumper(const ObjectFile *Obj,
309                                     ScopedPrinter &Writer,
310                                     std::unique_ptr<ObjDumper> &Result) {
311   if (!Obj)
312     return readobj_error::unsupported_file_format;
313 
314   if (Obj->isCOFF())
315     return createCOFFDumper(Obj, Writer, Result);
316   if (Obj->isELF())
317     return createELFDumper(Obj, Writer, Result);
318   if (Obj->isMachO())
319     return createMachODumper(Obj, Writer, Result);
320 
321   return readobj_error::unsupported_obj_file_format;
322 }
323 
324 /// @brief Dumps the specified object file.
325 static void dumpObject(const ObjectFile *Obj) {
326   ScopedPrinter Writer(outs());
327   std::unique_ptr<ObjDumper> Dumper;
328   if (std::error_code EC = createDumper(Obj, Writer, Dumper))
329     reportError(Obj->getFileName(), EC);
330 
331   if (opts::Output == opts::LLVM) {
332     outs() << '\n';
333     outs() << "File: " << Obj->getFileName() << "\n";
334     outs() << "Format: " << Obj->getFileFormatName() << "\n";
335     outs() << "Arch: " << Triple::getArchTypeName(
336                               (llvm::Triple::ArchType)Obj->getArch()) << "\n";
337     outs() << "AddressSize: " << (8 * Obj->getBytesInAddress()) << "bit\n";
338     Dumper->printLoadName();
339   }
340 
341   if (opts::FileHeaders)
342     Dumper->printFileHeaders();
343   if (opts::Sections)
344     Dumper->printSections();
345   if (opts::Relocations)
346     Dumper->printRelocations();
347   if (opts::DynRelocs)
348     Dumper->printDynamicRelocations();
349   if (opts::Symbols)
350     Dumper->printSymbols();
351   if (opts::DynamicSymbols)
352     Dumper->printDynamicSymbols();
353   if (opts::UnwindInfo)
354     Dumper->printUnwindInfo();
355   if (opts::DynamicTable)
356     Dumper->printDynamicTable();
357   if (opts::NeededLibraries)
358     Dumper->printNeededLibraries();
359   if (opts::ProgramHeaders)
360     Dumper->printProgramHeaders();
361   if (opts::HashTable)
362     Dumper->printHashTable();
363   if (opts::GnuHashTable)
364     Dumper->printGnuHashTable();
365   if (opts::VersionInfo)
366     Dumper->printVersionInfo();
367   if (Obj->isELF()) {
368     if (Obj->getArch() == llvm::Triple::arm)
369       if (opts::ARMAttributes)
370         Dumper->printAttributes();
371     if (isMipsArch(Obj->getArch())) {
372       if (opts::MipsPLTGOT)
373         Dumper->printMipsPLTGOT();
374       if (opts::MipsABIFlags)
375         Dumper->printMipsABIFlags();
376       if (opts::MipsReginfo)
377         Dumper->printMipsReginfo();
378       if (opts::MipsOptions)
379         Dumper->printMipsOptions();
380     }
381     if (opts::SectionGroups)
382       Dumper->printGroupSections();
383     if (opts::HashHistogram)
384       Dumper->printHashHistogram();
385   }
386   if (Obj->isCOFF()) {
387     if (opts::COFFImports)
388       Dumper->printCOFFImports();
389     if (opts::COFFExports)
390       Dumper->printCOFFExports();
391     if (opts::COFFDirectives)
392       Dumper->printCOFFDirectives();
393     if (opts::COFFBaseRelocs)
394       Dumper->printCOFFBaseReloc();
395     if (opts::CodeView)
396       Dumper->printCodeViewDebugInfo();
397     if (opts::CodeViewMergedTypes)
398       Dumper->mergeCodeViewTypes(CVTypes);
399   }
400   if (Obj->isMachO()) {
401     if (opts::MachODataInCode)
402       Dumper->printMachODataInCode();
403     if (opts::MachOIndirectSymbols)
404       Dumper->printMachOIndirectSymbols();
405     if (opts::MachOLinkerOptions)
406       Dumper->printMachOLinkerOptions();
407     if (opts::MachOSegment)
408       Dumper->printMachOSegment();
409     if (opts::MachOVersionMin)
410       Dumper->printMachOVersionMin();
411     if (opts::MachODysymtab)
412       Dumper->printMachODysymtab();
413   }
414   if (opts::PrintStackMap)
415     Dumper->printStackMap();
416 }
417 
418 /// @brief Dumps each object file in \a Arc;
419 static void dumpArchive(const Archive *Arc) {
420   for (auto &ErrorOrChild : Arc->children()) {
421     if (std::error_code EC = ErrorOrChild.getError())
422       reportError(Arc->getFileName(), EC.message());
423     const auto &Child = *ErrorOrChild;
424     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
425     if (!ChildOrErr) {
426       if (auto E = isNotObjectErrorInvalidFileType(ChildOrErr.takeError())) {
427         std::string Buf;
428         raw_string_ostream OS(Buf);
429         logAllUnhandledErrors(ChildOrErr.takeError(), OS, "");
430         OS.flush();
431         reportError(Arc->getFileName(), Buf);
432       }
433       continue;
434     }
435     if (ObjectFile *Obj = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
436       dumpObject(Obj);
437     else
438       reportError(Arc->getFileName(), readobj_error::unrecognized_file_format);
439   }
440 }
441 
442 /// @brief Dumps each object file in \a MachO Universal Binary;
443 static void dumpMachOUniversalBinary(const MachOUniversalBinary *UBinary) {
444   for (const MachOUniversalBinary::ObjectForArch &Obj : UBinary->objects()) {
445     Expected<std::unique_ptr<MachOObjectFile>> ObjOrErr = Obj.getAsObjectFile();
446     if (ObjOrErr)
447       dumpObject(&*ObjOrErr.get());
448     else if (auto E = isNotObjectErrorInvalidFileType(ObjOrErr.takeError())) {
449       std::string Buf;
450       raw_string_ostream OS(Buf);
451       logAllUnhandledErrors(ObjOrErr.takeError(), OS, "");
452       OS.flush();
453       reportError(UBinary->getFileName(), Buf);
454     }
455     else if (ErrorOr<std::unique_ptr<Archive>> AOrErr = Obj.getAsArchive())
456       dumpArchive(&*AOrErr.get());
457   }
458 }
459 
460 /// @brief Opens \a File and dumps it.
461 static void dumpInput(StringRef File) {
462 
463   // Attempt to open the binary.
464   Expected<OwningBinary<Binary>> BinaryOrErr = createBinary(File);
465   if (!BinaryOrErr)
466     reportError(File, errorToErrorCode(BinaryOrErr.takeError()));
467   Binary &Binary = *BinaryOrErr.get().getBinary();
468 
469   if (Archive *Arc = dyn_cast<Archive>(&Binary))
470     dumpArchive(Arc);
471   else if (MachOUniversalBinary *UBinary =
472                dyn_cast<MachOUniversalBinary>(&Binary))
473     dumpMachOUniversalBinary(UBinary);
474   else if (ObjectFile *Obj = dyn_cast<ObjectFile>(&Binary))
475     dumpObject(Obj);
476   else if (COFFImportFile *Import = dyn_cast<COFFImportFile>(&Binary))
477     dumpCOFFImportFile(Import);
478   else
479     reportError(File, readobj_error::unrecognized_file_format);
480 }
481 
482 int main(int argc, const char *argv[]) {
483   sys::PrintStackTraceOnErrorSignal();
484   PrettyStackTraceProgram X(argc, argv);
485   llvm_shutdown_obj Y;
486 
487   // Register the target printer for --version.
488   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
489 
490   cl::ParseCommandLineOptions(argc, argv, "LLVM Object Reader\n");
491 
492   // Default to stdin if no filename is specified.
493   if (opts::InputFilenames.size() == 0)
494     opts::InputFilenames.push_back("-");
495 
496   std::for_each(opts::InputFilenames.begin(), opts::InputFilenames.end(),
497                 dumpInput);
498 
499   if (opts::CodeViewMergedTypes) {
500     ScopedPrinter W(outs());
501     dumpCodeViewMergedTypes(W, CVTypes);
502   }
503 
504   return 0;
505 }
506