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 "StreamWriter.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/Signals.h"
39 #include "llvm/Support/TargetRegistry.h"
40 #include "llvm/Support/TargetSelect.h"
41 #include <string>
42 #include <system_error>
43 
44 using namespace llvm;
45 using namespace llvm::object;
46 
47 namespace opts {
48   cl::list<std::string> InputFilenames(cl::Positional,
49     cl::desc("<input object files>"),
50     cl::ZeroOrMore);
51 
52   // -file-headers, -h
53   cl::opt<bool> FileHeaders("file-headers",
54     cl::desc("Display file headers "));
55   cl::alias FileHeadersShort("h",
56     cl::desc("Alias for --file-headers"),
57     cl::aliasopt(FileHeaders));
58 
59   // -sections, -s
60   cl::opt<bool> Sections("sections",
61     cl::desc("Display all sections."));
62   cl::alias SectionsShort("s",
63     cl::desc("Alias for --sections"),
64     cl::aliasopt(Sections));
65 
66   // -section-relocations, -sr
67   cl::opt<bool> SectionRelocations("section-relocations",
68     cl::desc("Display relocations for each section shown."));
69   cl::alias SectionRelocationsShort("sr",
70     cl::desc("Alias for --section-relocations"),
71     cl::aliasopt(SectionRelocations));
72 
73   // -section-symbols, -st
74   cl::opt<bool> SectionSymbols("section-symbols",
75     cl::desc("Display symbols for each section shown."));
76   cl::alias SectionSymbolsShort("st",
77     cl::desc("Alias for --section-symbols"),
78     cl::aliasopt(SectionSymbols));
79 
80   // -section-data, -sd
81   cl::opt<bool> SectionData("section-data",
82     cl::desc("Display section data for each section shown."));
83   cl::alias SectionDataShort("sd",
84     cl::desc("Alias for --section-data"),
85     cl::aliasopt(SectionData));
86 
87   // -relocations, -r
88   cl::opt<bool> Relocations("relocations",
89     cl::desc("Display the relocation entries in the file"));
90   cl::alias RelocationsShort("r",
91     cl::desc("Alias for --relocations"),
92     cl::aliasopt(Relocations));
93 
94   // -dyn-relocations
95   cl::opt<bool> DynRelocs("dyn-relocations",
96     cl::desc("Display the dynamic relocation entries in the file"));
97 
98   // -symbols, -t
99   cl::opt<bool> Symbols("symbols",
100     cl::desc("Display the symbol table"));
101   cl::alias SymbolsShort("t",
102     cl::desc("Alias for --symbols"),
103     cl::aliasopt(Symbols));
104 
105   // -dyn-symbols, -dt
106   cl::opt<bool> DynamicSymbols("dyn-symbols",
107     cl::desc("Display the dynamic symbol table"));
108   cl::alias DynamicSymbolsShort("dt",
109     cl::desc("Alias for --dyn-symbols"),
110     cl::aliasopt(DynamicSymbols));
111 
112   // -unwind, -u
113   cl::opt<bool> UnwindInfo("unwind",
114     cl::desc("Display unwind information"));
115   cl::alias UnwindInfoShort("u",
116     cl::desc("Alias for --unwind"),
117     cl::aliasopt(UnwindInfo));
118 
119   // -dynamic-table
120   cl::opt<bool> DynamicTable("dynamic-table",
121     cl::desc("Display the ELF .dynamic section table"));
122 
123   // -needed-libs
124   cl::opt<bool> NeededLibraries("needed-libs",
125     cl::desc("Display the needed libraries"));
126 
127   // -program-headers
128   cl::opt<bool> ProgramHeaders("program-headers",
129     cl::desc("Display ELF program headers"));
130 
131   // -hash-table
132   cl::opt<bool> HashTable("hash-table",
133     cl::desc("Display ELF hash table"));
134 
135   // -gnu-hash-table
136   cl::opt<bool> GnuHashTable("gnu-hash-table",
137     cl::desc("Display ELF .gnu.hash section"));
138 
139   // -expand-relocs
140   cl::opt<bool> ExpandRelocs("expand-relocs",
141     cl::desc("Expand each shown relocation to multiple lines"));
142 
143   // -codeview
144   cl::opt<bool> CodeView("codeview",
145                          cl::desc("Display CodeView debug information"));
146 
147   // -codeview-subsection-bytes
148   cl::opt<bool> CodeViewSubsectionBytes(
149       "codeview-subsection-bytes",
150       cl::desc("Dump raw contents of codeview debug sections and records"));
151 
152   // -arm-attributes, -a
153   cl::opt<bool> ARMAttributes("arm-attributes",
154                               cl::desc("Display the ARM attributes section"));
155   cl::alias ARMAttributesShort("-a", cl::desc("Alias for --arm-attributes"),
156                                cl::aliasopt(ARMAttributes));
157 
158   // -mips-plt-got
159   cl::opt<bool>
160   MipsPLTGOT("mips-plt-got",
161              cl::desc("Display the MIPS GOT and PLT GOT sections"));
162 
163   // -mips-abi-flags
164   cl::opt<bool> MipsABIFlags("mips-abi-flags",
165                              cl::desc("Display the MIPS.abiflags section"));
166 
167   // -mips-reginfo
168   cl::opt<bool> MipsReginfo("mips-reginfo",
169                             cl::desc("Display the MIPS .reginfo section"));
170 
171   // -coff-imports
172   cl::opt<bool>
173   COFFImports("coff-imports", cl::desc("Display the PE/COFF import table"));
174 
175   // -coff-exports
176   cl::opt<bool>
177   COFFExports("coff-exports", cl::desc("Display the PE/COFF export table"));
178 
179   // -coff-directives
180   cl::opt<bool>
181   COFFDirectives("coff-directives",
182                  cl::desc("Display the PE/COFF .drectve section"));
183 
184   // -coff-basereloc
185   cl::opt<bool>
186   COFFBaseRelocs("coff-basereloc",
187                  cl::desc("Display the PE/COFF .reloc section"));
188 
189   // -macho-data-in-code
190   cl::opt<bool>
191   MachODataInCode("macho-data-in-code",
192                   cl::desc("Display MachO Data in Code command"));
193 
194   // -macho-indirect-symbols
195   cl::opt<bool>
196   MachOIndirectSymbols("macho-indirect-symbols",
197                   cl::desc("Display MachO indirect symbols"));
198 
199   // -macho-linker-options
200   cl::opt<bool>
201   MachOLinkerOptions("macho-linker-options",
202                   cl::desc("Display MachO linker options"));
203 
204   // -macho-segment
205   cl::opt<bool>
206   MachOSegment("macho-segment",
207                   cl::desc("Display MachO Segment command"));
208 
209   // -macho-version-min
210   cl::opt<bool>
211   MachOVersionMin("macho-version-min",
212                   cl::desc("Display MachO version min command"));
213 
214   // -macho-dysymtab
215   cl::opt<bool>
216   MachODysymtab("macho-dysymtab",
217                   cl::desc("Display MachO Dysymtab command"));
218 
219   // -stackmap
220   cl::opt<bool>
221   PrintStackMap("stackmap",
222                 cl::desc("Display contents of stackmap section"));
223 
224   // -version-info
225   cl::opt<bool>
226       VersionInfo("version-info",
227                   cl::desc("Display ELF version sections (if present)"));
228   cl::alias VersionInfoShort("V", cl::desc("Alias for -version-info"),
229                              cl::aliasopt(VersionInfo));
230 
231   cl::opt<bool> SectionGroups("elf-section-groups",
232                               cl::desc("Display ELF section group contents"));
233   cl::alias SectionGroupsShort("g", cl::desc("Alias for -elf-sections-groups"),
234                                cl::aliasopt(SectionGroups));
235 
236   cl::opt<OutputStyleTy>
237       Output("elf-output-style", cl::desc("Specify ELF dump style"),
238              cl::values(clEnumVal(LLVM, "LLVM default style"),
239                         clEnumVal(GNU, "GNU readelf style"), clEnumValEnd),
240              cl::init(LLVM));
241 } // namespace opts
242 
243 namespace llvm {
244 
245 LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg) {
246   errs() << "\nError reading file: " << Msg << ".\n";
247   errs().flush();
248   exit(1);
249 }
250 
251 void error(std::error_code EC) {
252   if (!EC)
253     return;
254 
255   reportError(EC.message());
256 }
257 
258 bool relocAddressLess(RelocationRef a, RelocationRef b) {
259   return a.getOffset() < b.getOffset();
260 }
261 
262 } // namespace llvm
263 
264 static void reportError(StringRef Input, std::error_code EC) {
265   if (Input == "-")
266     Input = "<stdin>";
267 
268   reportError(Twine(Input) + ": " + EC.message());
269 }
270 
271 static void reportError(StringRef Input, StringRef Message) {
272   if (Input == "-")
273     Input = "<stdin>";
274 
275   reportError(Twine(Input) + ": " + Message);
276 }
277 
278 static bool isMipsArch(unsigned Arch) {
279   switch (Arch) {
280   case llvm::Triple::mips:
281   case llvm::Triple::mipsel:
282   case llvm::Triple::mips64:
283   case llvm::Triple::mips64el:
284     return true;
285   default:
286     return false;
287   }
288 }
289 
290 /// @brief Creates an format-specific object file dumper.
291 static std::error_code createDumper(const ObjectFile *Obj, StreamWriter &Writer,
292                                     std::unique_ptr<ObjDumper> &Result) {
293   if (!Obj)
294     return readobj_error::unsupported_file_format;
295 
296   if (Obj->isCOFF())
297     return createCOFFDumper(Obj, Writer, Result);
298   if (Obj->isELF())
299     return createELFDumper(Obj, Writer, Result);
300   if (Obj->isMachO())
301     return createMachODumper(Obj, Writer, Result);
302 
303   return readobj_error::unsupported_obj_file_format;
304 }
305 
306 /// @brief Dumps the specified object file.
307 static void dumpObject(const ObjectFile *Obj) {
308   StreamWriter Writer(outs());
309   std::unique_ptr<ObjDumper> Dumper;
310   if (std::error_code EC = createDumper(Obj, Writer, Dumper))
311     reportError(Obj->getFileName(), EC);
312 
313   if (opts::Output == opts::LLVM) {
314     outs() << '\n';
315     outs() << "File: " << Obj->getFileName() << "\n";
316     outs() << "Format: " << Obj->getFileFormatName() << "\n";
317     outs() << "Arch: " << Triple::getArchTypeName(
318                               (llvm::Triple::ArchType)Obj->getArch()) << "\n";
319     outs() << "AddressSize: " << (8 * Obj->getBytesInAddress()) << "bit\n";
320     Dumper->printLoadName();
321   }
322 
323   if (opts::FileHeaders)
324     Dumper->printFileHeaders();
325   if (opts::Sections)
326     Dumper->printSections();
327   if (opts::Relocations)
328     Dumper->printRelocations();
329   if (opts::DynRelocs)
330     Dumper->printDynamicRelocations();
331   if (opts::Symbols)
332     Dumper->printSymbols();
333   if (opts::DynamicSymbols)
334     Dumper->printDynamicSymbols();
335   if (opts::UnwindInfo)
336     Dumper->printUnwindInfo();
337   if (opts::DynamicTable)
338     Dumper->printDynamicTable();
339   if (opts::NeededLibraries)
340     Dumper->printNeededLibraries();
341   if (opts::ProgramHeaders)
342     Dumper->printProgramHeaders();
343   if (opts::HashTable)
344     Dumper->printHashTable();
345   if (opts::GnuHashTable)
346     Dumper->printGnuHashTable();
347   if (opts::VersionInfo)
348     Dumper->printVersionInfo();
349   if (Obj->isELF()) {
350     if (Obj->getArch() == llvm::Triple::arm)
351       if (opts::ARMAttributes)
352         Dumper->printAttributes();
353     if (isMipsArch(Obj->getArch())) {
354       if (opts::MipsPLTGOT)
355         Dumper->printMipsPLTGOT();
356       if (opts::MipsABIFlags)
357         Dumper->printMipsABIFlags();
358       if (opts::MipsReginfo)
359         Dumper->printMipsReginfo();
360     }
361     if (opts::SectionGroups)
362       Dumper->printGroupSections();
363   }
364   if (Obj->isCOFF()) {
365     if (opts::COFFImports)
366       Dumper->printCOFFImports();
367     if (opts::COFFExports)
368       Dumper->printCOFFExports();
369     if (opts::COFFDirectives)
370       Dumper->printCOFFDirectives();
371     if (opts::COFFBaseRelocs)
372       Dumper->printCOFFBaseReloc();
373     if (opts::CodeView)
374       Dumper->printCodeViewDebugInfo();
375   }
376   if (Obj->isMachO()) {
377     if (opts::MachODataInCode)
378       Dumper->printMachODataInCode();
379     if (opts::MachOIndirectSymbols)
380       Dumper->printMachOIndirectSymbols();
381     if (opts::MachOLinkerOptions)
382       Dumper->printMachOLinkerOptions();
383     if (opts::MachOSegment)
384       Dumper->printMachOSegment();
385     if (opts::MachOVersionMin)
386       Dumper->printMachOVersionMin();
387     if (opts::MachODysymtab)
388       Dumper->printMachODysymtab();
389   }
390   if (opts::PrintStackMap)
391     Dumper->printStackMap();
392 }
393 
394 /// @brief Dumps each object file in \a Arc;
395 static void dumpArchive(const Archive *Arc) {
396   for (auto &ErrorOrChild : Arc->children()) {
397     if (std::error_code EC = ErrorOrChild.getError())
398       reportError(Arc->getFileName(), EC.message());
399     const auto &Child = *ErrorOrChild;
400     ErrorOr<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
401     if (std::error_code EC = ChildOrErr.getError()) {
402       // Ignore non-object files.
403       if (EC != object_error::invalid_file_type)
404         reportError(Arc->getFileName(), EC.message());
405       continue;
406     }
407 
408     if (ObjectFile *Obj = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
409       dumpObject(Obj);
410     else
411       reportError(Arc->getFileName(), readobj_error::unrecognized_file_format);
412   }
413 }
414 
415 /// @brief Dumps each object file in \a MachO Universal Binary;
416 static void dumpMachOUniversalBinary(const MachOUniversalBinary *UBinary) {
417   for (const MachOUniversalBinary::ObjectForArch &Obj : UBinary->objects()) {
418     ErrorOr<std::unique_ptr<MachOObjectFile>> ObjOrErr = Obj.getAsObjectFile();
419     if (ObjOrErr)
420       dumpObject(&*ObjOrErr.get());
421     else if (ErrorOr<std::unique_ptr<Archive>> AOrErr = Obj.getAsArchive())
422       dumpArchive(&*AOrErr.get());
423     else
424       reportError(UBinary->getFileName(), ObjOrErr.getError().message());
425   }
426 }
427 
428 /// @brief Opens \a File and dumps it.
429 static void dumpInput(StringRef File) {
430 
431   // Attempt to open the binary.
432   ErrorOr<OwningBinary<Binary>> BinaryOrErr = createBinary(File);
433   if (std::error_code EC = BinaryOrErr.getError())
434     reportError(File, EC);
435   Binary &Binary = *BinaryOrErr.get().getBinary();
436 
437   if (Archive *Arc = dyn_cast<Archive>(&Binary))
438     dumpArchive(Arc);
439   else if (MachOUniversalBinary *UBinary =
440                dyn_cast<MachOUniversalBinary>(&Binary))
441     dumpMachOUniversalBinary(UBinary);
442   else if (ObjectFile *Obj = dyn_cast<ObjectFile>(&Binary))
443     dumpObject(Obj);
444   else if (COFFImportFile *Import = dyn_cast<COFFImportFile>(&Binary))
445     dumpCOFFImportFile(Import);
446   else
447     reportError(File, readobj_error::unrecognized_file_format);
448 }
449 
450 int main(int argc, const char *argv[]) {
451   sys::PrintStackTraceOnErrorSignal();
452   PrettyStackTraceProgram X(argc, argv);
453   llvm_shutdown_obj Y;
454 
455   // Register the target printer for --version.
456   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
457 
458   cl::ParseCommandLineOptions(argc, argv, "LLVM Object Reader\n");
459 
460   // Default to stdin if no filename is specified.
461   if (opts::InputFilenames.size() == 0)
462     opts::InputFilenames.push_back("-");
463 
464   std::for_each(opts::InputFilenames.begin(), opts::InputFilenames.end(),
465                 dumpInput);
466 
467   return 0;
468 }
469