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 from itertools import ifilter
  13 import string
  14
  15 # If elftools is not installed, maybe we're running from the root or scripts
  16 # dir of the source distribution
  17 try:
  18     import elftools
  19 except ImportError:
  20     sys.path.extend(['.', '..'])
  21
  22 from elftools import __version__
  23 from elftools.common.exceptions import ELFError
  24 from elftools.elf.elffile import ELFFile
  25 from elftools.elf.segments import InterpSegment
  26 from elftools.elf.sections import SymbolTableSection
  27 from elftools.elf.relocation import RelocationSection
  28 from elftools.elf.descriptions import (
  29     describe_ei_class, describe_ei_data, describe_ei_version,
  30     describe_ei_osabi, describe_e_type, describe_e_machine,
  31     describe_e_version_numeric, describe_p_type, describe_p_flags,
  32     describe_sh_type, describe_sh_flags,
  33     describe_symbol_type, describe_symbol_bind, describe_symbol_visibility,
  34     describe_symbol_shndx, describe_reloc_type,
  35     )
  36 from elftools.dwarf.dwarfinfo import DWARFInfo
  37 from elftools.dwarf.descriptions import (
  38     describe_reg_name, describe_attr_value, set_global_machine_arch,
  39     describe_CFI_instructions, describe_CFI_register_rule,
  40     describe_CFI_CFA_rule,
  41     )
  42 from elftools.dwarf.constants import (
  43     DW_LNS_copy, DW_LNS_set_file, DW_LNE_define_file)
  44 from elftools.dwarf.callframe import CIE, FDE
  45
  46
  47 class ReadElf(object):
  48     """ display_* methods are used to emit output into the output stream
  49     """
  50     def __init__(self, file, output):
  51         """ file:
  52                 stream object with the ELF file to read
  53
  54             output:
  55                 output stream to write to
  56         """
  57         self.elffile = ELFFile(file)
  58         self.output = output
  59
  60         # Lazily initialized if a debug dump is requested
  61         self._dwarfinfo = None
  62
  63     def display_file_header(self):
  64         """ Display the ELF file header
  65         """
  66         self._emitline('ELF Header:')
  67         self._emit('  Magic:   ')
  68         self._emitline(' '.join('%2.2x' % ord(b)
  69                                     for b in self.elffile.e_ident_raw))
  70         header = self.elffile.header
  71         e_ident = header['e_ident']
  72         self._emitline('  Class:                             %s' %
  73                 describe_ei_class(e_ident['EI_CLASS']))
  74         self._emitline('  Data:                              %s' %
  75                 describe_ei_data(e_ident['EI_DATA']))
  76         self._emitline('  Version:                           %s' %
  77                 describe_ei_version(e_ident['EI_VERSION']))
  78         self._emitline('  OS/ABI:                            %s' %
  79                 describe_ei_osabi(e_ident['EI_OSABI']))
  80         self._emitline('  ABI Version:                       %d' %
  81                 e_ident['EI_ABIVERSION'])
  82         self._emitline('  Type:                              %s' %
  83                 describe_e_type(header['e_type']))
  84         self._emitline('  Machine:                           %s' %
  85                 describe_e_machine(header['e_machine']))
  86         self._emitline('  Version:                           %s' %
  87                 describe_e_version_numeric(header['e_version']))
  88         self._emitline('  Entry point address:               %s' %
  89                 self._format_hex(header['e_entry']))
  90         self._emit('  Start of program headers:          %s' %
  91                 header['e_phoff'])
  92         self._emitline(' (bytes into file)')
  93         self._emit('  Start of section headers:          %s' %
  94                 header['e_shoff'])
  95         self._emitline(' (bytes into file)')
  96         self._emitline('  Flags:                             %s' %
  97                 self._format_hex(header['e_flags']))
  98         self._emitline('  Size of this header:               %s (bytes)' %
  99                 header['e_ehsize'])
 100         self._emitline('  Size of program headers:           %s (bytes)' %
 101                 header['e_phentsize'])
 102         self._emitline('  Number of program headers:         %s' %
 103                 header['e_phnum'])
 104         self._emitline('  Size of section headers:           %s (bytes)' %
 105                 header['e_shentsize'])
 106         self._emitline('  Number of section headers:         %s' %
 107                 header['e_shnum'])
 108         self._emitline('  Section header string table index: %s' %
 109                 header['e_shstrndx'])
 110
 111     def display_program_headers(self, show_heading=True):
 112         """ Display the ELF program headers.
 113             If show_heading is True, displays the heading for this information
 114             (Elf file type is...)
 115         """
 116         self._emitline()
 117         if self.elffile.num_segments() == 0:
 118             self._emitline('There are no program headers in this file.')
 119             return
 120
 121         elfheader = self.elffile.header
 122         if show_heading:
 123             self._emitline('Elf file type is %s' %
 124                 describe_e_type(elfheader['e_type']))
 125             self._emitline('Entry point is %s' %
 126                 self._format_hex(elfheader['e_entry']))
 127             # readelf weirness - why isn't e_phoff printed as hex? (for section
 128             # headers, it is...)
 129             self._emitline('There are %s program headers, starting at offset %s' % (
 130                 elfheader['e_phnum'], elfheader['e_phoff']))
 131             self._emitline()
 132
 133         self._emitline('Program Headers:')
 134
 135         # Now comes the table of program headers with their attributes. Note
 136         # that due to different formatting constraints of 32-bit and 64-bit
 137         # addresses, there are some conditions on elfclass here.
 138         #
 139         # First comes the table heading
 140         #
 141         if self.elffile.elfclass == 32:
 142             self._emitline('  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align')
 143         else:
 144             self._emitline('  Type           Offset             VirtAddr           PhysAddr')
 145             self._emitline('                 FileSiz            MemSiz              Flags  Align')
 146
 147         # Now the entries
 148         #
 149         for segment in self.elffile.iter_segments():
 150             self._emit('  %-14s ' % describe_p_type(segment['p_type']))
 151
 152             if self.elffile.elfclass == 32:
 153                 self._emitline('%s %s %s %s %s %-3s %s' % (
 154                     self._format_hex(segment['p_offset'], fieldsize=6),
 155                     self._format_hex(segment['p_vaddr'], fullhex=True),
 156                     self._format_hex(segment['p_paddr'], fullhex=True),
 157                     self._format_hex(segment['p_filesz'], fieldsize=5),
 158                     self._format_hex(segment['p_memsz'], fieldsize=5),
 159                     describe_p_flags(segment['p_flags']),
 160                     self._format_hex(segment['p_align'])))
 161             else: # 64
 162                 self._emitline('%s %s %s' % (
 163                     self._format_hex(segment['p_offset'], fullhex=True),
 164                     self._format_hex(segment['p_vaddr'], fullhex=True),
 165                     self._format_hex(segment['p_paddr'], fullhex=True)))
 166                 self._emitline('                 %s %s  %-3s    %s' % (
 167                     self._format_hex(segment['p_filesz'], fullhex=True),
 168                     self._format_hex(segment['p_memsz'], fullhex=True),
 169                     describe_p_flags(segment['p_flags']),
 170                     # lead0x set to False for p_align, to mimic readelf.
 171                     # No idea why the difference from 32-bit mode :-|
 172                     self._format_hex(segment['p_align'], lead0x=False)))
 173
 174             if isinstance(segment, InterpSegment):
 175                 self._emitline('      [Requesting program interpreter: %s]' %
 176                     segment.get_interp_name())
 177
 178         # Sections to segments mapping
 179         #
 180         if self.elffile.num_sections() == 0:
 181             # No sections? We're done
 182             return
 183
 184         self._emitline('\n Section to Segment mapping:')
 185         self._emitline('  Segment Sections...')
 186
 187         for nseg, segment in enumerate(self.elffile.iter_segments()):
 188             self._emit('   %2.2d     ' % nseg)
 189
 190             for section in self.elffile.iter_sections():
 191                 if (    not section.is_null() and
 192                         segment.section_in_segment(section)):
 193                     self._emit('%s ' % section.name)
 194
 195             self._emitline('')
 196
 197     def display_section_headers(self, show_heading=True):
 198         """ Display the ELF section headers
 199         """
 200         elfheader = self.elffile.header
 201         if show_heading:
 202             self._emitline('There are %s section headers, starting at offset %s' % (
 203                 elfheader['e_shnum'], self._format_hex(elfheader['e_shoff'])))
 204
 205         self._emitline('\nSection Header%s:' % (
 206             's' if elfheader['e_shnum'] > 1 else ''))
 207
 208         # Different formatting constraints of 32-bit and 64-bit addresses
 209         #
 210         if self.elffile.elfclass == 32:
 211             self._emitline('  [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al')
 212         else:
 213             self._emitline('  [Nr] Name              Type             Address           Offset')
 214             self._emitline('       Size              EntSize          Flags  Link  Info  Align')
 215
 216         # Now the entries
 217         #
 218         for nsec, section in enumerate(self.elffile.iter_sections()):
 219             self._emit('  [%2u] %-17.17s %-15.15s ' % (
 220                 nsec, section.name, describe_sh_type(section['sh_type'])))
 221
 222             if self.elffile.elfclass == 32:
 223                 self._emitline('%s %s %s %s %3s %2s %3s %2s' % (
 224                     self._format_hex(section['sh_addr'], fieldsize=8, lead0x=False),
 225                     self._format_hex(section['sh_offset'], fieldsize=6, lead0x=False),
 226                     self._format_hex(section['sh_size'], fieldsize=6, lead0x=False),
 227                     self._format_hex(section['sh_entsize'], fieldsize=2, lead0x=False),
 228                     describe_sh_flags(section['sh_flags']),
 229                     section['sh_link'], section['sh_info'],
 230                     section['sh_addralign']))
 231             else: # 64
 232                 self._emitline(' %s  %s' % (
 233                     self._format_hex(section['sh_addr'], fullhex=True, lead0x=False),
 234                     self._format_hex(section['sh_offset'],
 235                         fieldsize=16 if section['sh_offset'] > 0xffffffff else 8,
 236                         lead0x=False)))
 237                 self._emitline('       %s  %s %3s      %2s   %3s     %s' % (
 238                     self._format_hex(section['sh_size'], fullhex=True, lead0x=False),
 239                     self._format_hex(section['sh_entsize'], fullhex=True, lead0x=False),
 240                     describe_sh_flags(section['sh_flags']),
 241                     section['sh_link'], section['sh_info'],
 242                     section['sh_addralign']))
 243
 244         self._emitline('Key to Flags:')
 245         self._emit('  W (write), A (alloc), X (execute), M (merge), S (strings)')
 246         if self.elffile['e_machine'] in ('EM_X86_64', 'EM_L10M'):
 247             self._emitline(', l (large)')
 248         else:
 249             self._emitline()
 250         self._emitline('  I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)')
 251         self._emitline('  O (extra OS processing required) o (OS specific), p (processor specific)')
 252
 253     def display_symbol_tables(self):
 254         """ Display the symbol tables contained in the file
 255         """
 256         for section in self.elffile.iter_sections():
 257             if not isinstance(section, SymbolTableSection):
 258                 continue
 259
 260             if section['sh_entsize'] == 0:
 261                 self._emitline("\nSymbol table '%s' has a sh_entsize of zero!" % (
 262                     section.name))
 263                 continue
 264
 265             self._emitline("\nSymbol table '%s' contains %s entries:" % (
 266                 section.name, section.num_symbols()))
 267
 268             if self.elffile.elfclass == 32:
 269                 self._emitline('   Num:    Value  Size Type    Bind   Vis      Ndx Name')
 270             else: # 64
 271                 self._emitline('   Num:    Value          Size Type    Bind   Vis      Ndx Name')
 272
 273             for nsym, symbol in enumerate(section.iter_symbols()):
 274                 # symbol names are truncated to 25 chars, similarly to readelf
 275                 self._emitline('%6d: %s %5d %-7s %-6s %-7s %4s %.25s' % (
 276                     nsym,
 277                     self._format_hex(symbol['st_value'], fullhex=True, lead0x=False),
 278                     symbol['st_size'],
 279                     describe_symbol_type(symbol['st_info']['type']),
 280                     describe_symbol_bind(symbol['st_info']['bind']),
 281                     describe_symbol_visibility(symbol['st_other']['visibility']),
 282                     describe_symbol_shndx(symbol['st_shndx']),
 283                     symbol.name))
 284
 285     def display_relocations(self):
 286         """ Display the relocations contained in the file
 287         """
 288         has_relocation_sections = False
 289         for section in self.elffile.iter_sections():
 290             if not isinstance(section, RelocationSection):
 291                 continue
 292
 293             has_relocation_sections = True
 294             self._emitline("\nRelocation section '%s' at offset %s contains %s entries:" % (
 295                 section.name,
 296                 self._format_hex(section['sh_offset']),
 297                 section.num_relocations()))
 298             if section.is_RELA():
 299                 self._emitline("  Offset          Info           Type           Sym. Value    Sym. Name + Addend")
 300             else:
 301                 self._emitline(" Offset     Info    Type            Sym.Value  Sym. Name")
 302
 303             # The symbol table section pointed to in sh_link
 304             symtable = self.elffile.get_section(section['sh_link'])
 305
 306             for rel in section.iter_relocations():
 307                 hexwidth = 8 if self.elffile.elfclass == 32 else 12
 308                 self._emit('%s  %s %-17.17s' % (
 309                     self._format_hex(rel['r_offset'],
 310                         fieldsize=hexwidth, lead0x=False),
 311                     self._format_hex(rel['r_info'],
 312                         fieldsize=hexwidth, lead0x=False),
 313                     describe_reloc_type(
 314                         rel['r_info_type'], self.elffile)))
 315
 316                 if rel['r_info_sym'] == 0:
 317                     self._emitline()
 318                     continue
 319
 320                 symbol = symtable.get_symbol(rel['r_info_sym'])
 321                 # Some symbols have zero 'st_name', so instead what's used is
 322                 # the name of the section they point at
 323                 if symbol['st_name'] == 0:
 324                     symsec = self.elffile.get_section(symbol['st_shndx'])
 325                     symbol_name = symsec.name
 326                 else:
 327                     symbol_name = symbol.name
 328                 self._emit(' %s %s%22.22s' % (
 329                     self._format_hex(
 330                         symbol['st_value'],
 331                         fullhex=True, lead0x=False),
 332                     '  ' if self.elffile.elfclass == 32 else '',
 333                     symbol_name))
 334                 if section.is_RELA():
 335                     self._emit(' %s %x' % (
 336                         '+' if rel['r_addend'] >= 0 else '-',
 337                         abs(rel['r_addend'])))
 338                 self._emitline()
 339
 340         if not has_relocation_sections:
 341             self._emitline('\nThere are no relocations in this file.')
 342
 343     def display_hex_dump(self, section_spec):
 344         """ Display a hex dump of a section. section_spec is either a section
 345             number or a name.
 346         """
 347         section = self._section_from_spec(section_spec)
 348         if section is None:
 349             self._emitline("Section '%s' does not exist in the file!" % (
 350                 section_spec))
 351             return
 352
 353         self._emitline("\nHex dump of section '%s':" % section.name)
 354         self._note_relocs_for_section(section)
 355         addr = section['sh_addr']
 356         data = section.data()
 357         dataptr = 0
 358
 359         while dataptr < len(data):
 360             bytesleft = len(data) - dataptr
 361             # chunks of 16 bytes per line
 362             linebytes = 16 if bytesleft > 16 else bytesleft
 363
 364             self._emit('  %s ' % self._format_hex(addr, fieldsize=8))
 365             for i in range(16):
 366                 if i < linebytes:
 367                     self._emit('%2.2x' % ord(data[dataptr + i]))
 368                 else:
 369                     self._emit('  ')
 370                 if i % 4 == 3:
 371                     self._emit(' ')
 372
 373             for i in range(linebytes):
 374                 c = data[dataptr + i]
 375                 if c >= ' ' and ord(c) < 0x7f:
 376                     self._emit(c)
 377                 else:
 378                     self._emit('.')
 379
 380             self._emitline()
 381             addr += linebytes
 382             dataptr += linebytes
 383
 384         self._emitline()
 385
 386     def display_string_dump(self, section_spec):
 387         """ Display a strings dump of a section. section_spec is either a
 388             section number or a name.
 389         """
 390         section = self._section_from_spec(section_spec)
 391         if section is None:
 392             self._emitline("Section '%s' does not exist in the file!" % (
 393                 section_spec))
 394             return
 395
 396         printables = set(string.printable)
 397         self._emitline("\nString dump of section '%s':" % section.name)
 398
 399         found = False
 400         data = section.data()
 401         dataptr = 0
 402
 403         while dataptr < len(data):
 404             while dataptr < len(data) and data[dataptr] not in printables:
 405                 dataptr += 1
 406
 407             if dataptr >= len(data):
 408                 break
 409
 410             endptr = dataptr
 411             while endptr < len(data) and data[endptr] != '\x00':
 412                 endptr += 1
 413
 414             found = True
 415             self._emitline('  [%6x]  %s' % (
 416                 dataptr, data[dataptr:endptr]))
 417
 418             dataptr = endptr
 419
 420         if not found:
 421             self._emitline('  No strings found in this section.')
 422         else:
 423             self._emitline()
 424
 425     def display_debug_dump(self, dump_what):
 426         """ Dump a DWARF section
 427         """
 428         self._init_dwarfinfo()
 429         if self._dwarfinfo is None:
 430             return
 431
 432         set_global_machine_arch(self.elffile.get_machine_arch())
 433
 434         if dump_what == 'info':
 435             self._dump_debug_info()
 436         elif dump_what == 'decodedline':
 437             self._dump_debug_line_programs()
 438         elif dump_what == 'frames':
 439             self._dump_debug_frames()
 440         elif dump_what == 'frames-interp':
 441             self._dump_debug_frames_interp()
 442         else:
 443             self._emitline('debug dump not yet supported for "%s"' % dump_what)
 444
 445     def _format_hex(self, addr, fieldsize=None, fullhex=False, lead0x=True):
 446         """ Format an address into a hexadecimal string.
 447
 448             fieldsize:
 449                 Size of the hexadecimal field (with leading zeros to fit the
 450                 address into. For example with fieldsize=8, the format will
 451                 be %08x
 452                 If None, the minimal required field size will be used.
 453
 454             fullhex:
 455                 If True, override fieldsize to set it to the maximal size
 456                 needed for the elfclass
 457
 458             lead0x:
 459                 If True, leading 0x is added
 460         """
 461         s = '0x' if lead0x else ''
 462         if fullhex:
 463             fieldsize = 8 if self.elffile.elfclass == 32 else 16
 464         if fieldsize is None:
 465             field = '%x'
 466         else:
 467             field = '%' + '0%sx' % fieldsize
 468         return s + field % addr
 469
 470     def _section_from_spec(self, spec):
 471         """ Retrieve a section given a "spec" (either number or name).
 472             Return None if no such section exists in the file.
 473         """
 474         try:
 475             num = int(spec)
 476             if num < self.elffile.num_sections():
 477                 return self.elffile.get_section(num)
 478             else:
 479                 return None
 480         except ValueError:
 481             # Not a number. Must be a name then
 482             return self.elffile.get_section_by_name(spec)
 483
 484     def _note_relocs_for_section(self, section):
 485         """ If there are relocation sections pointing to the givne section,
 486             emit a note about it.
 487         """
 488         for relsec in self.elffile.iter_sections():
 489             if isinstance(relsec, RelocationSection):
 490                 info_idx = relsec['sh_info']
 491                 if self.elffile.get_section(info_idx) == section:
 492                     self._emitline('  Note: This section has relocations against it, but these have NOT been applied to this dump.')
 493                     return
 494
 495     def _init_dwarfinfo(self):
 496         """ Initialize the DWARF info contained in the file and assign it to
 497             self._dwarfinfo.
 498             Leave self._dwarfinfo at None if no DWARF info was found in the file
 499         """
 500         if self._dwarfinfo is not None:
 501             return
 502
 503         if self.elffile.has_dwarf_info():
 504             self._dwarfinfo = self.elffile.get_dwarf_info()
 505         else:
 506             self._dwarfinfo = None
 507
 508     def _dump_debug_info(self):
 509         """ Dump the debugging info section.
 510         """
 511         self._emitline('Contents of the .debug_info section:\n')
 512
 513         # Offset of the .debug_info section in the stream
 514         section_offset = self._dwarfinfo.debug_info_sec.global_offset
 515
 516         for cu in self._dwarfinfo.iter_CUs():
 517             self._emitline('  Compilation Unit @ offset %s:' %
 518                 self._format_hex(cu.cu_offset))
 519             self._emitline('   Length:        %s (%s)' % (
 520                 self._format_hex(cu['unit_length']),
 521                 '%s-bit' % cu.dwarf_format()))
 522             self._emitline('   Version:       %s' % cu['version']),
 523             self._emitline('   Abbrev Offset: %s' % cu['debug_abbrev_offset']),
 524             self._emitline('   Pointer Size:  %s' % cu['address_size'])
 525
 526             # The nesting depth of each DIE within the tree of DIEs must be
 527             # displayed. To implement this, a counter is incremented each time
 528             # the current DIE has children, and decremented when a null die is
 529             # encountered. Due to the way the DIE tree is serialized, this will
 530             # correctly reflect the nesting depth
 531             #
 532             die_depth = 0
 533             for die in cu.iter_DIEs():
 534                 if die.is_null():
 535                     die_depth -= 1
 536                     continue
 537                 self._emitline(' <%s><%x>: Abbrev Number: %s (%s)' % (
 538                     die_depth,
 539                     die.offset,
 540                     die.abbrev_code,
 541                     die.tag))
 542
 543                 for attr in die.attributes.itervalues():
 544                     name = attr.name
 545                     # Unknown attribute values are passed-through as integers
 546                     if isinstance(name, int):
 547                         name = 'Unknown AT value: %x' % name
 548                     self._emitline('    <%2x>   %-18s: %s' % (
 549                         attr.offset,
 550                         name,
 551                         describe_attr_value(
 552                             attr, die, section_offset)))
 553
 554                 if die.has_children:
 555                     die_depth += 1
 556
 557         self._emitline()
 558
 559     def _dump_debug_line_programs(self):
 560         """ Dump the (decoded) line programs from .debug_line
 561             The programs are dumped in the order of the CUs they belong to.
 562         """
 563         self._emitline('Decoded dump of debug contents of section .debug_line:\n')
 564
 565         for cu in self._dwarfinfo.iter_CUs():
 566             lineprogram = self._dwarfinfo.line_program_for_CU(cu)
 567
 568             cu_filename = ''
 569             if len(lineprogram['include_directory']) > 0:
 570                 cu_filename = '%s/%s' % (
 571                     lineprogram['include_directory'][0],
 572                     lineprogram['file_entry'][0].name)
 573             else:
 574                 cu_filename = lineprogram['file_entry'][0].name
 575
 576             self._emitline('CU: %s:' % cu_filename)
 577             self._emitline('File name                            Line number    Starting address')
 578
 579             # Print each state's file, line and address information. For some
 580             # instructions other output is needed to be compatible with
 581             # readelf.
 582             for entry in lineprogram.get_entries():
 583                 state = entry.state
 584                 if state is None:
 585                     # Special handling for commands that don't set a new state
 586                     if entry.command == DW_LNS_set_file:
 587                         file_entry = lineprogram['file_entry'][entry.args[0] - 1]
 588                         if file_entry.dir_index == 0:
 589                             # current directory
 590                             self._emitline('\n./%s:[++]' % (
 591                                 file_entry.name))
 592                         else:
 593                             self._emitline('\n%s/%s:' % (
 594                                 lineprogram['include_directory'][file_entry.dir_index - 1],
 595                                 file_entry.name))
 596                     elif entry.command == DW_LNE_define_file:
 597                         self._emitline('%s:' % (
 598                             lineprogram['include_directory'][entry.args[0].dir_index]))
 599                 elif not state.end_sequence:
 600                     # readelf doesn't print the state after end_sequence
 601                     # instructions. I think it's a bug but to be compatible
 602                     # I don't print them too.
 603                     self._emitline('%-35s  %11d  %18s' % (
 604                         lineprogram['file_entry'][state.file - 1].name,
 605                         state.line,
 606                         '0' if state.address == 0 else
 607                                self._format_hex(state.address)))
 608                 if entry.command == DW_LNS_copy:
 609                     # Another readelf oddity...
 610                     self._emitline()
 611
 612     def _dump_debug_frames(self):
 613         """ Dump the raw frame information from .debug_frame
 614         """
 615         if not self._dwarfinfo.has_CFI():
 616             return
 617         self._emitline('Contents of the .debug_frame section:')
 618
 619         for entry in self._dwarfinfo.CFI_entries():
 620             if isinstance(entry, CIE):
 621                 self._emitline('\n%08x %08x %08x CIE' % (
 622                     entry.offset, entry['length'], entry['CIE_id']))
 623                 self._emitline('  Version:               %d' % entry['version'])
 624                 self._emitline('  Augmentation:          "%s"' % entry['augmentation'])
 625                 self._emitline('  Code alignment factor: %u' % entry['code_alignment_factor'])
 626                 self._emitline('  Data alignment factor: %d' % entry['data_alignment_factor'])
 627                 self._emitline('  Return address column: %d' % entry['return_address_register'])
 628                 self._emitline()
 629             else: # FDE
 630                 self._emitline('\n%08x %08x %08x FDE cie=%08x pc=%08x..%08x' % (
 631                     entry.offset,
 632                     entry['length'],
 633                     entry['CIE_pointer'],
 634                     entry.cie.offset,
 635                     entry['initial_location'],
 636                     entry['initial_location'] + entry['address_range']))
 637
 638             self._emit(describe_CFI_instructions(entry))
 639         self._emitline()
 640
 641     def _dump_debug_frames_interp(self):
 642         """ Dump the interpreted (decoded) frame information from .debug_frame
 643         """
 644         if not self._dwarfinfo.has_CFI():
 645             return
 646
 647         self._emitline('Contents of the .debug_frame section:')
 648
 649         for entry in self._dwarfinfo.CFI_entries():
 650             if isinstance(entry, CIE):
 651                 self._emitline('\n%08x %08x %08x CIE "%s" cf=%d df=%d ra=%d' % (
 652                     entry.offset,
 653                     entry['length'],
 654                     entry['CIE_id'],
 655                     entry['augmentation'],
 656                     entry['code_alignment_factor'],
 657                     entry['data_alignment_factor'],
 658                     entry['return_address_register']))
 659                 ra_regnum = entry['return_address_register']
 660             else: # FDE
 661                 self._emitline('\n%08x %08x %08x FDE cie=%08x pc=%08x..%08x' % (
 662                     entry.offset,
 663                     entry['length'],
 664                     entry['CIE_pointer'],
 665                     entry.cie.offset,
 666                     entry['initial_location'],
 667                     entry['initial_location'] + entry['address_range']))
 668                 ra_regnum = entry.cie['return_address_register']
 669
 670             # Print the heading row for the decoded table
 671             self._emit('   LOC')
 672             self._emit('  ' if entry.structs.address_size == 4 else '          ')
 673             self._emit(' CFA      ')
 674
 675             # Decode the table nad look at the registers it describes.
 676             # We build reg_order here to match readelf's order. In particular,
 677             # registers are sorted by their number, and the register matching
 678             # ra_regnum is always listed last with a special heading.
 679             decoded_table = entry.get_decoded()
 680             reg_order = sorted(ifilter(
 681                 lambda r: r != ra_regnum,
 682                 decoded_table.reg_order))
 683
 684             # Headings for the registers
 685             for regnum in reg_order:
 686                 self._emit('%-6s' % describe_reg_name(regnum))
 687             self._emitline('ra      ')
 688
 689             # Now include ra_regnum in reg_order to print its values similarly
 690             # to the other registers.
 691             reg_order.append(ra_regnum)
 692             for line in decoded_table.table:
 693                 self._emit(self._format_hex(
 694                     line['pc'], fullhex=True, lead0x=False))
 695                 self._emit(' %-9s' % describe_CFI_CFA_rule(line['cfa']))
 696
 697                 for regnum in reg_order:
 698                     if regnum in line:
 699                         s = describe_CFI_register_rule(line[regnum])
 700                     else:
 701                         s = 'u'
 702                     self._emit('%-6s' % s)
 703                 self._emitline()
 704         self._emitline()
 705
 706     def _emit(self, s=''):
 707         """ Emit an object to output
 708         """
 709         self.output.write(str(s))
 710
 711     def _emitline(self, s=''):
 712         """ Emit an object to output, followed by a newline
 713         """
 714         self.output.write(str(s) + '\n')
 715
 716
 717 SCRIPT_DESCRIPTION = 'Display information about the contents of ELF format files'
 718 VERSION_STRING = '%%prog: based on pyelftools %s' % __version__
 719
 720
 721 def main(stream=None):
 722     # parse the command-line arguments and invoke ReadElf
 723     optparser = OptionParser(
 724             usage='usage: %prog [options] <elf-file>',
 725             description=SCRIPT_DESCRIPTION,
 726             add_help_option=False, # -h is a real option of readelf
 727             prog='readelf.py',
 728             version=VERSION_STRING)
 729     optparser.add_option('-H', '--help',
 730             action='store_true', dest='help',
 731             help='Display this information')
 732     optparser.add_option('-h', '--file-header',
 733             action='store_true', dest='show_file_header',
 734             help='Display the ELF file header')
 735     optparser.add_option('-l', '--program-headers', '--segments',
 736             action='store_true', dest='show_program_header',
 737             help='Display the program headers')
 738     optparser.add_option('-S', '--section-headers', '--sections',
 739             action='store_true', dest='show_section_header',
 740             help="Display the sections' headers")
 741     optparser.add_option('-e', '--headers',
 742             action='store_true', dest='show_all_headers',
 743             help='Equivalent to: -h -l -S')
 744     optparser.add_option('-s', '--symbols', '--syms',
 745             action='store_true', dest='show_symbols',
 746             help='Display the symbol table')
 747     optparser.add_option('-r', '--relocs',
 748             action='store_true', dest='show_relocs',
 749             help='Display the relocations (if present)')
 750     optparser.add_option('-x', '--hex-dump',
 751             action='store', dest='show_hex_dump', metavar='<number|name>',
 752             help='Dump the contents of section <number|name> as bytes')
 753     optparser.add_option('-p', '--string-dump',
 754             action='store', dest='show_string_dump', metavar='<number|name>',
 755             help='Dump the contents of section <number|name> as strings')
 756     optparser.add_option('--debug-dump',
 757             action='store', dest='debug_dump_what', metavar='<what>',
 758             help=(
 759                 'Display the contents of DWARF debug sections. <what> can ' +
 760                 'one of {info,decodedline,frames,frames-interp}'))
 761
 762     options, args = optparser.parse_args()
 763
 764     if options.help or len(args) == 0:
 765         optparser.print_help()
 766         sys.exit(0)
 767
 768     if options.show_all_headers:
 769         do_file_header = do_section_header = do_program_header = True
 770     else:
 771         do_file_header = options.show_file_header
 772         do_section_header = options.show_section_header
 773         do_program_header = options.show_program_header
 774
 775     with open(args[0], 'rb') as file:
 776         try:
 777             readelf = ReadElf(file, stream or sys.stdout)
 778             if do_file_header:
 779                 readelf.display_file_header()
 780             if do_section_header:
 781                 readelf.display_section_headers(
 782                         show_heading=not do_file_header)
 783             if do_program_header:
 784                 readelf.display_program_headers(
 785                         show_heading=not do_file_header)
 786             if options.show_symbols:
 787                 readelf.display_symbol_tables()
 788             if options.show_relocs:
 789                 readelf.display_relocations()
 790             if options.show_hex_dump:
 791                 readelf.display_hex_dump(options.show_hex_dump)
 792             if options.show_string_dump:
 793                 readelf.display_string_dump(options.show_string_dump)
 794             if options.debug_dump_what:
 795                 readelf.display_debug_dump(options.debug_dump_what)
 796         except ELFError as ex:
 797             sys.stderr.write('ELF error: %s\n' % ex)
 798             sys.exit(1)
 799
 800
 801 def profile_main():
 802     # Run 'main' redirecting its output to readelfout.txt
 803     # Saves profiling information in readelf.profile
 804     PROFFILE = 'readelf.profile'
 805     import cProfile
 806     cProfile.run('main(open("readelfout.txt", "w"))', PROFFILE)
 807
 808     # Dig in some profiling stats
 809     import pstats
 810     p = pstats.Stats(PROFFILE)
 811     p.sort_stats('cumulative').print_stats(25)
 812
 813
 814 #-------------------------------------------------------------------------------
 815 if __name__ == '__main__':
 816     main()
 817     #profile_main()
 818
 819