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 } // namespace opts
237 
238 namespace llvm {
239 
240 LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg) {
241   errs() << "\nError reading file: " << Msg << ".\n";
242   errs().flush();
243   exit(1);
244 }
245 
246 void error(std::error_code EC) {
247   if (!EC)
248     return;
249 
250   reportError(EC.message());
251 }
252 
253 bool relocAddressLess(RelocationRef a, RelocationRef b) {
254   return a.getOffset() < b.getOffset();
255 }
256 
257 } // namespace llvm
258 
259 static void reportError(StringRef Input, std::error_code EC) {
260   if (Input == "-")
261     Input = "<stdin>";
262 
263   reportError(Twine(Input) + ": " + EC.message());
264 }
265 
266 static void reportError(StringRef Input, StringRef Message) {
267   if (Input == "-")
268     Input = "<stdin>";
269 
270   reportError(Twine(Input) + ": " + Message);
271 }
272 
273 static bool isMipsArch(unsigned Arch) {
274   switch (Arch) {
275   case llvm::Triple::mips:
276   case llvm::Triple::mipsel:
277   case llvm::Triple::mips64:
278   case llvm::Triple::mips64el:
279     return true;
280   default:
281     return false;
282   }
283 }
284 
285 /// @brief Creates an format-specific object file dumper.
286 static std::error_code createDumper(const ObjectFile *Obj, StreamWriter &Writer,
287                                     std::unique_ptr<ObjDumper> &Result) {
288   if (!Obj)
289     return readobj_error::unsupported_file_format;
290 
291   if (Obj->isCOFF())
292     return createCOFFDumper(Obj, Writer, Result);
293   if (Obj->isELF())
294     return createELFDumper(Obj, Writer, Result);
295   if (Obj->isMachO())
296     return createMachODumper(Obj, Writer, Result);
297 
298   return readobj_error::unsupported_obj_file_format;
299 }
300 
301 /// @brief Dumps the specified object file.
302 static void dumpObject(const ObjectFile *Obj) {
303   StreamWriter Writer(outs());
304   std::unique_ptr<ObjDumper> Dumper;
305   if (std::error_code EC = createDumper(Obj, Writer, Dumper))
306     reportError(Obj->getFileName(), EC);
307 
308   outs() << '\n';
309   outs() << "File: " << Obj->getFileName() << "\n";
310   outs() << "Format: " << Obj->getFileFormatName() << "\n";
311   outs() << "Arch: "
312          << Triple::getArchTypeName((llvm::Triple::ArchType)Obj->getArch())
313          << "\n";
314   outs() << "AddressSize: " << (8*Obj->getBytesInAddress()) << "bit\n";
315   Dumper->printLoadName();
316 
317   if (opts::FileHeaders)
318     Dumper->printFileHeaders();
319   if (opts::Sections)
320     Dumper->printSections();
321   if (opts::Relocations)
322     Dumper->printRelocations();
323   if (opts::DynRelocs)
324     Dumper->printDynamicRelocations();
325   if (opts::Symbols)
326     Dumper->printSymbols();
327   if (opts::DynamicSymbols)
328     Dumper->printDynamicSymbols();
329   if (opts::UnwindInfo)
330     Dumper->printUnwindInfo();
331   if (opts::DynamicTable)
332     Dumper->printDynamicTable();
333   if (opts::NeededLibraries)
334     Dumper->printNeededLibraries();
335   if (opts::ProgramHeaders)
336     Dumper->printProgramHeaders();
337   if (opts::HashTable)
338     Dumper->printHashTable();
339   if (opts::GnuHashTable)
340     Dumper->printGnuHashTable();
341   if (opts::VersionInfo)
342     Dumper->printVersionInfo();
343   if (Obj->isELF()) {
344     if (Obj->getArch() == llvm::Triple::arm)
345       if (opts::ARMAttributes)
346         Dumper->printAttributes();
347     if (isMipsArch(Obj->getArch())) {
348       if (opts::MipsPLTGOT)
349         Dumper->printMipsPLTGOT();
350       if (opts::MipsABIFlags)
351         Dumper->printMipsABIFlags();
352       if (opts::MipsReginfo)
353         Dumper->printMipsReginfo();
354     }
355     if (opts::SectionGroups)
356       Dumper->printGroupSections();
357   }
358   if (Obj->isCOFF()) {
359     if (opts::COFFImports)
360       Dumper->printCOFFImports();
361     if (opts::COFFExports)
362       Dumper->printCOFFExports();
363     if (opts::COFFDirectives)
364       Dumper->printCOFFDirectives();
365     if (opts::COFFBaseRelocs)
366       Dumper->printCOFFBaseReloc();
367     if (opts::CodeView)
368       Dumper->printCodeViewDebugInfo();
369   }
370   if (Obj->isMachO()) {
371     if (opts::MachODataInCode)
372       Dumper->printMachODataInCode();
373     if (opts::MachOIndirectSymbols)
374       Dumper->printMachOIndirectSymbols();
375     if (opts::MachOLinkerOptions)
376       Dumper->printMachOLinkerOptions();
377     if (opts::MachOSegment)
378       Dumper->printMachOSegment();
379     if (opts::MachOVersionMin)
380       Dumper->printMachOVersionMin();
381     if (opts::MachODysymtab)
382       Dumper->printMachODysymtab();
383   }
384   if (opts::PrintStackMap)
385     Dumper->printStackMap();
386 }
387 
388 /// @brief Dumps each object file in \a Arc;
389 static void dumpArchive(const Archive *Arc) {
390   for (auto &ErrorOrChild : Arc->children()) {
391     if (std::error_code EC = ErrorOrChild.getError())
392       reportError(Arc->getFileName(), EC.message());
393     const auto &Child = *ErrorOrChild;
394     ErrorOr<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
395     if (std::error_code EC = ChildOrErr.getError()) {
396       // Ignore non-object files.
397       if (EC != object_error::invalid_file_type)
398         reportError(Arc->getFileName(), EC.message());
399       continue;
400     }
401 
402     if (ObjectFile *Obj = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
403       dumpObject(Obj);
404     else
405       reportError(Arc->getFileName(), readobj_error::unrecognized_file_format);
406   }
407 }
408 
409 /// @brief Dumps each object file in \a MachO Universal Binary;
410 static void dumpMachOUniversalBinary(const MachOUniversalBinary *UBinary) {
411   for (const MachOUniversalBinary::ObjectForArch &Obj : UBinary->objects()) {
412     ErrorOr<std::unique_ptr<MachOObjectFile>> ObjOrErr = Obj.getAsObjectFile();
413     if (ObjOrErr)
414       dumpObject(&*ObjOrErr.get());
415     else if (ErrorOr<std::unique_ptr<Archive>> AOrErr = Obj.getAsArchive())
416       dumpArchive(&*AOrErr.get());
417     else
418       reportError(UBinary->getFileName(), ObjOrErr.getError().message());
419   }
420 }
421 
422 /// @brief Opens \a File and dumps it.
423 static void dumpInput(StringRef File) {
424 
425   // Attempt to open the binary.
426   ErrorOr<OwningBinary<Binary>> BinaryOrErr = createBinary(File);
427   if (std::error_code EC = BinaryOrErr.getError())
428     reportError(File, EC);
429   Binary &Binary = *BinaryOrErr.get().getBinary();
430 
431   if (Archive *Arc = dyn_cast<Archive>(&Binary))
432     dumpArchive(Arc);
433   else if (MachOUniversalBinary *UBinary =
434                dyn_cast<MachOUniversalBinary>(&Binary))
435     dumpMachOUniversalBinary(UBinary);
436   else if (ObjectFile *Obj = dyn_cast<ObjectFile>(&Binary))
437     dumpObject(Obj);
438   else if (COFFImportFile *Import = dyn_cast<COFFImportFile>(&Binary))
439     dumpCOFFImportFile(Import);
440   else
441     reportError(File, readobj_error::unrecognized_file_format);
442 }
443 
444 int main(int argc, const char *argv[]) {
445   sys::PrintStackTraceOnErrorSignal();
446   PrettyStackTraceProgram X(argc, argv);
447   llvm_shutdown_obj Y;
448 
449   // Register the target printer for --version.
450   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
451 
452   cl::ParseCommandLineOptions(argc, argv, "LLVM Object Reader\n");
453 
454   // Default to stdin if no filename is specified.
455   if (opts::InputFilenames.size() == 0)
456     opts::InputFilenames.push_back("-");
457 
458   std::for_each(opts::InputFilenames.begin(), opts::InputFilenames.end(),
459                 dumpInput);
460 
461   return 0;
462 }
463