scripts/readelf.py

   1 #!/usr/bin/env python
   2 #-------------------------------------------------------------------------------
   3 # scripts/readelf.py
   4 #
   5 # A clone of 'readelf' in Python, based on the pyelftools library
   6 #
   7 # Eli Bendersky (eliben@gmail.com)
   8 # This code is in the public domain
   9 #-------------------------------------------------------------------------------
  10 import os, sys
  11 from optparse import OptionParser
  12 import string
  13
  14
  15 # If elftools is not installed, maybe we're running from the root or scripts
  16 # dir of the source distribution
  17 #
  18 try:
  19     import elftools
  20 except ImportError:
  21     sys.path.extend(['.', '..'])
  22
  23 from elftools import __version__
  24 from elftools.common.exceptions import ELFError
  25 from elftools.elf.elffile import ELFFile
  26 from elftools.elf.segments import InterpSegment
  27 from elftools.elf.sections import SymbolTableSection
  28 from elftools.elf.relocation import RelocationSection
  29 from elftools.elf.descriptions import (
  30     describe_ei_class, describe_ei_data, describe_ei_version,
  31     describe_ei_osabi, describe_e_type, describe_e_machine,
  32     describe_e_version_numeric, describe_p_type, describe_p_flags,
  33     describe_sh_type, describe_sh_flags,
  34     describe_symbol_type, describe_symbol_bind, describe_symbol_visibility,
  35     describe_symbol_shndx, describe_reloc_type,
  36     )
  37 from elftools.dwarf.dwarfinfo import DWARFInfo
  38 from elftools.dwarf.descriptions import (
  39     describe_attr_value, set_global_machine_arch, describe_CFI_instructions)
  40 from elftools.dwarf.constants import (
  41     DW_LNS_copy, DW_LNS_set_file, DW_LNE_define_file)
  42 from elftools.dwarf.callframe import CIE, FDE
  43
  44
  45 class ReadElf(object):
  46     """ display_* methods are used to emit output into the output stream
  47     """
  48     def __init__(self, file, output):
  49         """ file:
  50                 stream object with the ELF file to read
  51
  52             output:
  53                 output stream to write to
  54         """
  55         self.elffile = ELFFile(file)
  56         self.output = output
  57
  58         # Lazily initialized if a debug dump is requested
  59         self._dwarfinfo = None
  60
  61     def display_file_header(self):
  62         """ Display the ELF file header
  63         """
  64         self._emitline('ELF Header:')
  65         self._emit('  Magic:   ')
  66         self._emitline(' '.join('%2.2x' % ord(b)
  67                                     for b in self.elffile.e_ident_raw))
  68         header = self.elffile.header
  69         e_ident = header['e_ident']
  70         self._emitline('  Class:                             %s' %
  71                 describe_ei_class(e_ident['EI_CLASS']))
  72         self._emitline('  Data:                              %s' %
  73                 describe_ei_data(e_ident['EI_DATA']))
  74         self._emitline('  Version:                           %s' %
  75                 describe_ei_version(e_ident['EI_VERSION']))
  76         self._emitline('  OS/ABI:                            %s' %
  77                 describe_ei_osabi(e_ident['EI_OSABI']))
  78         self._emitline('  ABI Version:                       %d' %
  79                 e_ident['EI_ABIVERSION'])
  80         self._emitline('  Type:                              %s' %
  81                 describe_e_type(header['e_type']))
  82         self._emitline('  Machine:                           %s' %
  83                 describe_e_machine(header['e_machine']))
  84         self._emitline('  Version:                           %s' %
  85                 describe_e_version_numeric(header['e_version']))
  86         self._emitline('  Entry point address:               %s' %
  87                 self._format_hex(header['e_entry']))
  88         self._emit('  Start of program headers:          %s' %
  89                 header['e_phoff'])
  90         self._emitline(' (bytes into file)')
  91         self._emit('  Start of section headers:          %s' %
  92                 header['e_shoff'])
  93         self._emitline(' (bytes into file)')
  94         self._emitline('  Flags:                             %s' %
  95                 self._format_hex(header['e_flags']))
  96         self._emitline('  Size of this header:               %s (bytes)' %
  97                 header['e_ehsize'])
  98         self._emitline('  Size of program headers:           %s (bytes)' %
  99                 header['e_phentsize'])
 100         self._emitline('  Number of program headers:         %s' %
 101                 header['e_phnum'])
 102         self._emitline('  Size of section headers:           %s (bytes)' %
 103                 header['e_shentsize'])
 104         self._emitline('  Number of section headers:         %s' %
 105                 header['e_shnum'])
 106         self._emitline('  Section header string table index: %s' %
 107                 header['e_shstrndx'])
 108
 109     def display_program_headers(self, show_heading=True):
 110         """ Display the ELF program headers.
 111             If show_heading is True, displays the heading for this information
 112             (Elf file type is...)
 113         """
 114         self._emitline()
 115         if self.elffile.num_segments() == 0:
 116             self._emitline('There are no program headers in this file.')
 117             return
 118
 119         elfheader = self.elffile.header
 120         if show_heading:
 121             self._emitline('Elf file type is %s' %
 122                 describe_e_type(elfheader['e_type']))
 123             self._emitline('Entry point is %s' %
 124                 self._format_hex(elfheader['e_entry']))
 125             # readelf weirness - why isn't e_phoff printed as hex? (for section
 126             # headers, it is...)
 127             self._emitline('There are %s program headers, starting at offset %s' % (
 128                 elfheader['e_phnum'], elfheader['e_phoff']))
 129             self._emitline()
 130
 131         self._emitline('Program Headers:')
 132
 133         # Now comes the table of program headers with their attributes. Note
 134         # that due to different formatting constraints of 32-bit and 64-bit
 135         # addresses, there are some conditions on elfclass here.
 136         #
 137         # First comes the table heading
 138         #
 139         if self.elffile.elfclass == 32:
 140             self._emitline('  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align')
 141         else:
 142             self._emitline('  Type           Offset             VirtAddr           PhysAddr')
 143             self._emitline('                 FileSiz            MemSiz              Flags  Align')
 144
 145         # Now the entries
 146         #
 147         for segment in self.elffile.iter_segments():
 148             self._emit('  %-14s ' % describe_p_type(segment['p_type']))
 149
 150             if self.elffile.elfclass == 32:
 151                 self._emitline('%s %s %s %s %s %-3s %s' % (
 152                     self._format_hex(segment['p_offset'], fieldsize=6),
 153                     self._format_hex(segment['p_vaddr'], fullhex=True),
 154                     self._format_hex(segment['p_paddr'], fullhex=True),
 155                     self._format_hex(segment['p_filesz'], fieldsize=5),
 156                     self._format_hex(segment['p_memsz'], fieldsize=5),
 157                     describe_p_flags(segment['p_flags']),
 158                     self._format_hex(segment['p_align'])))
 159             else: # 64
 160                 self._emitline('%s %s %s' % (
 161                     self._format_hex(segment['p_offset'], fullhex=True),
 162                     self._format_hex(segment['p_vaddr'], fullhex=True),
 163                     self._format_hex(segment['p_paddr'], fullhex=True)))
 164                 self._emitline('                 %s %s  %-3s    %s' % (
 165                     self._format_hex(segment['p_filesz'], fullhex=True),
 166                     self._format_hex(segment['p_memsz'], fullhex=True),
 167                     describe_p_flags(segment['p_flags']),
 168                     # lead0x set to False for p_align, to mimic readelf.
 169                     # No idea why the difference from 32-bit mode :-|
 170                     self._format_hex(segment['p_align'], lead0x=False)))
 171
 172             if isinstance(segment, InterpSegment):
 173                 self._emitline('      [Requesting program interpreter: %s]' %
 174                     segment.get_interp_name())
 175
 176         # Sections to segments mapping
 177         #
 178         if self.elffile.num_sections() == 0:
 179             # No sections? We're done
 180             return
 181
 182         self._emitline('\n Section to Segment mapping:')
 183         self._emitline('  Segment Sections...')
 184
 185         for nseg, segment in enumerate(self.elffile.iter_segments()):
 186             self._emit('   %2.2d     ' % nseg)
 187
 188             for section in self.elffile.iter_sections():
 189                 if (    not section.is_null() and
 190                         segment.section_in_segment(section)):
 191                     self._emit('%s ' % section.name)
 192
 193             self._emitline('')
 194
 195     def display_section_headers(self, show_heading=True):
 196         """ Display the ELF section headers
 197         """
 198         elfheader = self.elffile.header
 199         if show_heading:
 200             self._emitline('There are %s section headers, starting at offset %s' % (
 201                 elfheader['e_shnum'], self._format_hex(elfheader['e_shoff'])))
 202
 203         self._emitline('\nSection Header%s:' % (
 204             's' if elfheader['e_shnum'] > 1 else ''))
 205
 206         # Different formatting constraints of 32-bit and 64-bit addresses
 207         #
 208         if self.elffile.elfclass == 32:
 209             self._emitline('  [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al')
 210         else:
 211             self._emitline('  [Nr] Name              Type             Address           Offset')
 212             self._emitline('       Size              EntSize          Flags  Link  Info  Align')
 213
 214         # Now the entries
 215         #
 216         for nsec, section in enumerate(self.elffile.iter_sections()):
 217             self._emit('  [%2u] %-17.17s %-15.15s ' % (
 218                 nsec, section.name, describe_sh_type(section['sh_type'])))
 219
 220             if self.elffile.elfclass == 32:
 221                 self._emitline('%s %s %s %s %3s %2s %3s %2s' % (
 222                     self._format_hex(section['sh_addr'], fieldsize=8, lead0x=False),
 223                     self._format_hex(section['sh_offset'], fieldsize=6, lead0x=False),
 224                     self._format_hex(section['sh_size'], fieldsize=6, lead0x=False),
 225                     self._format_hex(section['sh_entsize'], fieldsize=2, lead0x=False),
 226                     describe_sh_flags(section['sh_flags']),
 227                     section['sh_link'], section['sh_info'],
 228                     section['sh_addralign']))
 229             else: # 64
 230                 self._emitline(' %s  %s' % (
 231                     self._format_hex(section['sh_addr'], fullhex=True, lead0x=False),
 232                     self._format_hex(section['sh_offset'],
 233                         fieldsize=16 if section['sh_offset'] > 0xffffffff else 8,
 234                         lead0x=False)))
 235                 self._emitline('       %s  %s %3s      %2s   %3s     %s' % (
 236                     self._format_hex(section['sh_size'], fullhex=True, lead0x=False),
 237                     self._format_hex(section['sh_entsize'], fullhex=True, lead0x=False),
 238                     describe_sh_flags(section['sh_flags']),
 239                     section['sh_link'], section['sh_info'],
 240                     section['sh_addralign']))
 241
 242         self._emitline('Key to Flags:')
 243         self._emit('  W (write), A (alloc), X (execute), M (merge), S (strings)')
 244         if self.elffile['e_machine'] in ('EM_X86_64', 'EM_L10M'):
 245             self._emitline(', l (large)')
 246         else:
 247             self._emitline()
 248         self._emitline('  I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)')
 249         self._emitline('  O (extra OS processing required) o (OS specific), p (processor specific)')
 250
 251     def display_symbol_tables(self):
 252         """ Display the symbol tables contained in the file
 253         """
 254         for section in self.elffile.iter_sections():
 255             if not isinstance(section, SymbolTableSection):
 256                 continue
 257
 258             if section['sh_entsize'] == 0:
 259                 self._emitline("\nSymbol table '%s' has a sh_entsize of zero!" % (
 260                     section.name))
 261                 continue
 262
 263             self._emitline("\nSymbol table '%s' contains %s entries:" % (
 264                 section.name, section.num_symbols()))
 265
 266             if self.elffile.elfclass == 32:
 267                 self._emitline('   Num:    Value  Size Type    Bind   Vis      Ndx Name')
 268             else: # 64
 269                 self._emitline('   Num:    Value          Size Type    Bind   Vis      Ndx Name')
 270
 271             for nsym, symbol in enumerate(section.iter_symbols()):
 272                 # symbol names are truncated to 25 chars, similarly to readelf
 273                 self._emitline('%6d: %s %5d %-7s %-6s %-7s %4s %.25s' % (
 274                     nsym,
 275                     self._format_hex(symbol['st_value'], fullhex=True, lead0x=False),
 276                     symbol['st_size'],
 277                     describe_symbol_type(symbol['st_info']['type']),
 278                     describe_symbol_bind(symbol['st_info']['bind']),
 279                     describe_symbol_visibility(symbol['st_other']['visibility']),
 280                     describe_symbol_shndx(symbol['st_shndx']),
 281                     symbol.name))
 282
 283     def display_relocations(self):
 284         """ Display the relocations contained in the file
 285         """
 286         has_relocation_sections = False
 287         for section in self.elffile.iter_sections():
 288             if not isinstance(section, RelocationSection):
 289                 continue
 290
 291             has_relocation_sections = True
 292             self._emitline("\nRelocation section '%s' at offset %s contains %s entries:" % (
 293                 section.name,
 294                 self._format_hex(section['sh_offset']),
 295                 section.num_relocations()))
 296             if section.is_RELA():
 297                 self._emitline("  Offset          Info           Type           Sym. Value    Sym. Name + Addend")
 298             else:
 299                 self._emitline(" Offset     Info    Type            Sym.Value  Sym. Name")
 300
 301             # The symbol table section pointed to in sh_link
 302             symtable = self.elffile.get_section(section['sh_link'])
 303
 304             for rel in section.iter_relocations():
 305                 hexwidth = 8 if self.elffile.elfclass == 32 else 12
 306                 self._emit('%s  %s %-17.17s' % (
 307                     self._format_hex(rel['r_offset'],
 308                         fieldsize=hexwidth, lead0x=False),
 309                     self._format_hex(rel['r_info'],
 310                         fieldsize=hexwidth, lead0x=False),
 311                     describe_reloc_type(
 312                         rel['r_info_type'], self.elffile)))
 313
 314                 if rel['r_info_sym'] == 0:
 315                     self._emitline()
 316                     continue
 317
 318                 symbol = symtable.get_symbol(rel['r_info_sym'])
 319                 # Some symbols have zero 'st_name', so instead what's used is
 320                 # the name of the section they point at
 321                 if symbol['st_name'] == 0:
 322                     symsec = self.elffile.get_section(symbol['st_shndx'])
 323                     symbol_name = symsec.name
 324                 else:
 325                     symbol_name = symbol.name
 326                 self._emit(' %s %s%22.22s' % (
 327                     self._format_hex(
 328                         symbol['st_value'],
 329                         fullhex=True, lead0x=False),
 330                     '  ' if self.elffile.elfclass == 32 else '',
 331                     symbol_name))
 332                 if section.is_RELA():
 333                     self._emit(' %s %x' % (
 334                         '+' if rel['r_addend'] >= 0 else '-',
 335                         abs(rel['r_addend'])))
 336                 self._emitline()
 337
 338         if not has_relocation_sections:
 339             self._emitline('\nThere are no relocations in this file.')
 340
 341     def display_hex_dump(self, section_spec):
 342         """ Display a hex dump of a section. section_spec is either a section
 343             number or a name.
 344         """
 345         section = self._section_from_spec(section_spec)
 346         if section is None:
 347             self._emitline("Section '%s' does not exist in the file!" % (
 348                 section_spec))
 349             return
 350
 351         self._emitline("\nHex dump of section '%s':" % section.name)
 352         self._note_relocs_for_section(section)
 353         addr = section['sh_addr']
 354         data = section.data()
 355         dataptr = 0
 356
 357         while dataptr < len(data):
 358             bytesleft = len(data) - dataptr
 359             # chunks of 16 bytes per line
 360             linebytes = 16 if bytesleft > 16 else bytesleft
 361
 362             self._emit('  %s ' % self._format_hex(addr, fieldsize=8))
 363             for i in range(16):
 364                 if i < linebytes:
 365                     self._emit('%2.2x' % ord(data[dataptr + i]))
 366                 else:
 367                     self._emit('  ')
 368                 if i % 4 == 3:
 369                     self._emit(' ')
 370
 371             for i in range(linebytes):
 372                 c = data[dataptr + i]
 373                 if c >= ' ' and ord(c) < 0x7f:
 374                     self._emit(c)
 375                 else:
 376                     self._emit('.')
 377
 378             self._emitline()
 379             addr += linebytes
 380             dataptr += linebytes
 381
 382         self._emitline()
 383
 384     def display_string_dump(self, section_spec):
 385         """ Display a strings dump of a section. section_spec is either a
 386             section number or a name.
 387         """
 388         section = self._section_from_spec(section_spec)
 389         if section is None:
 390             self._emitline("Section '%s' does not exist in the file!" % (
 391                 section_spec))
 392             return
 393
 394         printables = set(string.printable)
 395         self._emitline("\nString dump of section '%s':" % section.name)
 396
 397         found = False
 398         data = section.data()
 399         dataptr = 0
 400
 401         while dataptr < len(data):
 402             while dataptr < len(data) and data[dataptr] not in printables:
 403                 dataptr += 1
 404
 405             if dataptr >= len(data):
 406                 break
 407
 408             endptr = dataptr
 409             while endptr < len(data) and data[endptr] != '\x00':
 410                 endptr += 1
 411
 412             found = True
 413             self._emitline('  [%6x]  %s' % (
 414                 dataptr, data[dataptr:endptr]))
 415
 416             dataptr = endptr
 417
 418         if not found:
 419             self._emitline('  No strings found in this section.')
 420         else:
 421             self._emitline()
 422
 423     def display_debug_dump(self, dump_what):
 424         """ Dump a DWARF section
 425         """
 426         self._init_dwarfinfo()
 427         if self._dwarfinfo is None:
 428             return
 429
 430         set_global_machine_arch(self.elffile.get_machine_arch())
 431
 432         if dump_what == 'info':
 433             self._dump_debug_info()
 434         elif dump_what == 'decodedline':
 435             self._dump_debug_line_programs()
 436         elif dump_what == 'frames':
 437             self._dump_debug_frames()
 438         else:
 439             self._emitline('debug dump not yet supported for "%s"' % dump_what)
 440
 441     def _format_hex(self, addr, fieldsize=None, fullhex=False, lead0x=True):
 442         """ Format an address into a hexadecimal string.
 443
 444             fieldsize:
 445                 Size of the hexadecimal field (with leading zeros to fit the
 446                 address into. For example with fieldsize=8, the format will
 447                 be %08x
 448                 If None, the minimal required field size will be used.
 449
 450             fullhex:
 451                 If True, override fieldsize to set it to the maximal size
 452                 needed for the elfclass
 453
 454             lead0x:
 455                 If True, leading 0x is added
 456         """
 457         s = '0x' if lead0x else ''
 458         if fullhex:
 459             fieldsize = 8 if self.elffile.elfclass == 32 else 16
 460         if fieldsize is None:
 461             field = '%x'
 462         else:
 463             field = '%' + '0%sx' % fieldsize
 464         return s + field % addr
 465
 466     def _section_from_spec(self, spec):
 467         """ Retrieve a section given a "spec" (either number or name).
 468             Return None if no such section exists in the file.
 469         """
 470         try:
 471             num = int(spec)
 472             if num < self.elffile.num_sections():
 473                 return self.elffile.get_section(num)
 474             else:
 475                 return None
 476         except ValueError:
 477             # Not a number. Must be a name then
 478             return self.elffile.get_section_by_name(spec)
 479
 480     def _note_relocs_for_section(self, section):
 481         """ If there are relocation sections pointing to the givne section,
 482             emit a note about it.
 483         """
 484         for relsec in self.elffile.iter_sections():
 485             if isinstance(relsec, RelocationSection):
 486                 info_idx = relsec['sh_info']
 487                 if self.elffile.get_section(info_idx) == section:
 488                     self._emitline('  Note: This section has relocations against it, but these have NOT been applied to this dump.')
 489                     return
 490
 491     def _init_dwarfinfo(self):
 492         """ Initialize the DWARF info contained in the file and assign it to
 493             self._dwarfinfo.
 494             Leave self._dwarfinfo at None if no DWARF info was found in the file
 495         """
 496         if self._dwarfinfo is not None:
 497             return
 498
 499         if self.elffile.has_dwarf_info():
 500             self._dwarfinfo = self.elffile.get_dwarf_info()
 501         else:
 502             self._dwarfinfo = None
 503
 504     def _dump_debug_info(self):
 505         """ Dump the debugging info section.
 506         """
 507         self._emitline('Contents of the .debug_info section:\n')
 508
 509         # Offset of the .debug_info section in the stream
 510         section_offset = self._dwarfinfo.debug_info_sec.global_offset
 511
 512         for cu in self._dwarfinfo.iter_CUs():
 513             self._emitline('  Compilation Unit @ offset %s:' %
 514                 self._format_hex(cu.cu_offset))
 515             self._emitline('   Length:        %s (%s)' % (
 516                 self._format_hex(cu['unit_length']),
 517                 '%s-bit' % cu.dwarf_format()))
 518             self._emitline('   Version:       %s' % cu['version']),
 519             self._emitline('   Abbrev Offset: %s' % cu['debug_abbrev_offset']),
 520             self._emitline('   Pointer Size:  %s' % cu['address_size'])
 521
 522             # The nesting depth of each DIE within the tree of DIEs must be
 523             # displayed. To implement this, a counter is incremented each time
 524             # the current DIE has children, and decremented when a null die is
 525             # encountered. Due to the way the DIE tree is serialized, this will
 526             # correctly reflect the nesting depth
 527             #
 528             die_depth = 0
 529             for die in cu.iter_DIEs():
 530                 if die.is_null():
 531                     die_depth -= 1
 532                     continue
 533                 self._emitline(' <%s><%x>: Abbrev Number: %s (%s)' % (
 534                     die_depth,
 535                     die.offset,
 536                     die.abbrev_code,
 537                     die.tag))
 538
 539                 for attr in die.attributes.itervalues():
 540                     self._emitline('    <%2x>   %-18s: %s' % (
 541                         attr.offset,
 542                         attr.name,
 543                         describe_attr_value(
 544                             attr, die, section_offset)))
 545
 546                 if die.has_children:
 547                     die_depth += 1
 548
 549         self._emitline()
 550
 551     def _dump_debug_line_programs(self):
 552         """ Dump the (decoded) line programs from .debug_line
 553             The programs are dumped in the order of the CUs they belong to.
 554         """
 555         self._emitline('Decoded dump of debug contents of section .debug_line:\n')
 556
 557         for cu in self._dwarfinfo.iter_CUs():
 558             lineprogram = self._dwarfinfo.line_program_for_CU(cu)
 559
 560             cu_filename = ''
 561             if len(lineprogram['include_directory']) > 0:
 562                 cu_filename = '%s/%s' % (
 563                     lineprogram['include_directory'][0],
 564                     lineprogram['file_entry'][0].name)
 565             else:
 566                 cu_filename = lineprogram['file_entry'][0].name
 567
 568             self._emitline('CU: %s:' % cu_filename)
 569             self._emitline('File name                            Line number    Starting address')
 570
 571             # Print each state's file, line and address information. For some
 572             # instructions other output is needed to be compatible with
 573             # readelf.
 574             for entry in lineprogram.get_entries():
 575                 state = entry.state
 576                 if state is None:
 577                     # Special handling for commands that don't set a new state
 578                     if entry.command == DW_LNS_set_file:
 579                         file_entry = lineprogram['file_entry'][entry.args[0] - 1]
 580                         if file_entry.dir_index == 0:
 581                             # current directory
 582                             self._emitline('\n./%s:[++]' % (
 583                                 file_entry.name))
 584                         else:
 585                             self._emitline('\n%s/%s:' % (
 586                                 lineprogram['include_directory'][file_entry.dir_index - 1],
 587                                 file_entry.name))
 588                     elif entry.command == DW_LNE_define_file:
 589                         self._emitline('%s:' % (
 590                             lineprogram['include_directory'][entry.args[0].dir_index]))
 591                 elif not state.end_sequence:
 592                     # readelf doesn't print the state after end_sequence
 593                     # instructions. I think it's a bug but to be compatible
 594                     # I don't print them too.
 595                     self._emitline('%-35s  %11d  %18s' % (
 596                         lineprogram['file_entry'][state.file - 1].name,
 597                         state.line,
 598                         '0' if state.address == 0 else
 599                                self._format_hex(state.address)))
 600                 if entry.command == DW_LNS_copy:
 601                     # Another readelf oddity...
 602                     self._emitline()
 603
 604     def _dump_debug_frames(self):
 605         """ Dump the raw frame information from .debug_frame
 606         """
 607         if not self._dwarfinfo.has_CFI():
 608             return
 609         self._emitline('Contents of the .debug_frame section:')
 610
 611         for entry in self._dwarfinfo.CFI_entries():
 612             if isinstance(entry, CIE):
 613                 self._emitline('\n%08x %08x %08x CIE' % (
 614                     entry.offset, entry['length'], entry['CIE_id']))
 615                 self._emitline('  Version:               %d' % entry['version'])
 616                 self._emitline('  Augmentation:          "%s"' % entry['augmentation'])
 617                 self._emitline('  Code alignment factor: %u' % entry['code_alignment_factor'])
 618                 self._emitline('  Data alignment factor: %d' % entry['data_alignment_factor'])
 619                 self._emitline('  Return address column: %d' % entry['return_address_register'])
 620                 self._emitline()
 621             else: # FDE
 622                 self._emitline('\n%08x %08x %08x FDE cie=%08x pc=%08x..%08x' % (
 623                     entry.offset,
 624                     entry['length'],
 625                     entry['CIE_pointer'],
 626                     entry.cie.offset,
 627                     entry['initial_location'],
 628                     entry['initial_location'] + entry['address_range']))
 629
 630             self._emit(describe_CFI_instructions(entry))
 631         self._emitline()
 632
 633     def _emit(self, s=''):
 634         """ Emit an object to output
 635         """
 636         self.output.write(str(s))
 637
 638     def _emitline(self, s=''):
 639         """ Emit an object to output, followed by a newline
 640         """
 641         self.output.write(str(s) + '\n')
 642
 643
 644 SCRIPT_DESCRIPTION = 'Display information about the contents of ELF format files'
 645 VERSION_STRING = '%%prog: based on pyelftools %s' % __version__
 646
 647
 648 def main(stream=None):
 649     # parse the command-line arguments and invoke ReadElf
 650     optparser = OptionParser(
 651             usage='usage: %prog [options] <elf-file>',
 652             description=SCRIPT_DESCRIPTION,
 653             add_help_option=False, # -h is a real option of readelf
 654             prog='readelf.py',
 655             version=VERSION_STRING)
 656     optparser.add_option('-H', '--help',
 657             action='store_true', dest='help',
 658             help='Display this information')
 659     optparser.add_option('-h', '--file-header',
 660             action='store_true', dest='show_file_header',
 661             help='Display the ELF file header')
 662     optparser.add_option('-l', '--program-headers', '--segments',
 663             action='store_true', dest='show_program_header',
 664             help='Display the program headers')
 665     optparser.add_option('-S', '--section-headers', '--sections',
 666             action='store_true', dest='show_section_header',
 667             help="Display the sections' headers")
 668     optparser.add_option('-e', '--headers',
 669             action='store_true', dest='show_all_headers',
 670             help='Equivalent to: -h -l -S')
 671     optparser.add_option('-s', '--symbols', '--syms',
 672             action='store_true', dest='show_symbols',
 673             help='Display the symbol table')
 674     optparser.add_option('-r', '--relocs',
 675             action='store_true', dest='show_relocs',
 676             help='Display the relocations (if present)')
 677     optparser.add_option('-x', '--hex-dump',
 678             action='store', dest='show_hex_dump', metavar='<number|name>',
 679             help='Dump the contents of section <number|name> as bytes')
 680     optparser.add_option('-p', '--string-dump',
 681             action='store', dest='show_string_dump', metavar='<number|name>',
 682             help='Dump the contents of section <number|name> as strings')
 683     optparser.add_option('--debug-dump',
 684             action='store', dest='debug_dump_what', metavar='<section>',
 685             help='Display the contents of DWARF debug sections')
 686
 687     options, args = optparser.parse_args()
 688
 689     if options.help or len(args) == 0:
 690         optparser.print_help()
 691         sys.exit(0)
 692
 693     if options.show_all_headers:
 694         do_file_header = do_section_header = do_program_header = True
 695     else:
 696         do_file_header = options.show_file_header
 697         do_section_header = options.show_section_header
 698         do_program_header = options.show_program_header
 699
 700     with open(args[0], 'rb') as file:
 701         try:
 702             readelf = ReadElf(file, stream or sys.stdout)
 703             if do_file_header:
 704                 readelf.display_file_header()
 705             if do_section_header:
 706                 readelf.display_section_headers(
 707                         show_heading=not do_file_header)
 708             if do_program_header:
 709                 readelf.display_program_headers(
 710                         show_heading=not do_file_header)
 711             if options.show_symbols:
 712                 readelf.display_symbol_tables()
 713             if options.show_relocs:
 714                 readelf.display_relocations()
 715             if options.show_hex_dump:
 716                 readelf.display_hex_dump(options.show_hex_dump)
 717             if options.show_string_dump:
 718                 readelf.display_string_dump(options.show_string_dump)
 719             if options.debug_dump_what:
 720                 readelf.display_debug_dump(options.debug_dump_what)
 721         except ELFError as ex:
 722             sys.stderr.write('ELF error: %s\n' % ex)
 723             sys.exit(1)
 724
 725
 726 def profile_main():
 727     # Run 'main' redirecting its output to readelfout.txt
 728     # Saves profiling information in readelf.profile
 729     PROFFILE = 'readelf.profile'
 730     import cProfile
 731     cProfile.run('main(open("readelfout.txt", "w"))', PROFFILE)
 732
 733     # Dig in some profiling stats
 734     import pstats
 735     p = pstats.Stats(PROFFILE)
 736     p.sort_stats('cumulative').print_stats(25)
 737
 738
 739 #-------------------------------------------------------------------------------
 740 if __name__ == '__main__':
 741     main()
 742     #profile_main()
 743
 744