#!/usr/bin/env python import struct import sys import StringIO class Reader: def __init__(self, path): if path == "-": # Snarf all the data so we can seek. self.file = StringIO.StringIO(sys.stdin.read()) else: self.file = open(path, "rb") self.isLSB = None self.is64Bit = None def seek(self, pos): self.file.seek(pos) def read(self, N): data = self.file.read(N) if len(data) != N: raise ValueError, "Out of data!" return data def read8(self): return ord(self.read(1)) def read16(self): return struct.unpack('><'[self.isLSB] + 'H', self.read(2))[0] def read32(self): return struct.unpack('><'[self.isLSB] + 'I', self.read(4))[0] def read32S(self): return struct.unpack('><'[self.isLSB] + 'i', self.read(4))[0] def read64(self): return struct.unpack('><'[self.isLSB] + 'Q', self.read(8))[0] def read64S(self): return struct.unpack('><'[self.isLSB] + 'q', self.read(8))[0] def readWord(self): if self.is64Bit: return self.read64() else: return self.read32() def readWordS(self): if self.is64Bit: return self.read64S() else: return self.read32S() class StringTable: def __init__(self, strings): self.string_table = strings def __getitem__(self, index): end = self.string_table.index('\x00', index) return self.string_table[index:end] class Section: def __init__(self, f): self.sh_name = f.read32() self.sh_type = f.read32() self.sh_flags = f.readWord() self.sh_addr = f.readWord() self.sh_offset = f.readWord() self.sh_size = f.readWord() self.sh_link = f.read32() self.sh_info = f.read32() self.sh_addralign = f.readWord() self.sh_entsize = f.readWord() def dump(self, shstrtab, f, strtab, dumpdata): print " (('sh_name', %d) # %r" % (self.sh_name, shstrtab[self.sh_name]) print " ('sh_type', %d)" % self.sh_type print " ('sh_flags', %d)" % self.sh_flags print " ('sh_addr', %d)" % self.sh_addr print " ('sh_offset', %d)" % self.sh_offset print " ('sh_size', %d)" % self.sh_size print " ('sh_link', %d)" % self.sh_link print " ('sh_info', %d)" % self.sh_info print " ('sh_addralign', %d)" % self.sh_addralign print " ('sh_entsize', %d)" % self.sh_entsize if self.sh_type == 2: # SHT_SYMTAB print " ('_symbols', [" dumpSymtab(f, self, strtab) print " ])" elif self.sh_type == 4 or self.sh_type == 9: # SHT_RELA / SHT_REL print " ('_relocations', [" dumpRel(f, self, self.sh_type == 4) print " ])" elif dumpdata: f.seek(self.sh_offset) print " ('_section_data', %r)" % f.read(self.sh_size) print " )," def dumpSymtab(f, section, strtab): entries = section.sh_size // section.sh_entsize for index in range(entries): f.seek(section.sh_offset + index * section.sh_entsize) print " # Symbol %d" % index name = f.read32() print " (('st_name', %d) # %r" % (name, strtab[name]) if not f.is64Bit: print " ('st_value', %d)" % f.read32() print " ('st_size', %d)" % f.read32() st_info = f.read8() print " ('st_bind', %d)" % (st_info >> 4) print " ('st_type', %d)" % (st_info & 0xf) print " ('st_other', %d)" % f.read8() print " ('st_shndx', %d)" % f.read16() if f.is64Bit: print " ('st_value', %d)" % f.read64() print " ('st_size', %d)" % f.read64() print " )," def dumpRel(f, section, dumprela = False): entries = section.sh_size // section.sh_entsize for index in range(entries): f.seek(section.sh_offset + index * section.sh_entsize) print " # Relocation %d" % index print " (('r_offset', %d)" % f.readWord() r_info = f.readWord() if f.is64Bit: print " ('r_sym', %d)" % (r_info >> 32) print " ('r_type', %d)" % (r_info & 0xffffffff) else: print " ('r_sym', %d)" % (r_info >> 8) print " ('r_type', %d)" % (r_info & 0xff) if dumprela: print " ('r_addend', %d)" % f.readWordS() print " )," def dumpELF(path, opts): f = Reader(path) magic = f.read(4) assert magic == '\x7FELF' fileclass = f.read8() if fileclass == 1: # ELFCLASS32 f.is64Bit = False elif fileclass == 2: # ELFCLASS64 f.is64Bit = True else: raise ValueError, "Unknown file class %d" % fileclass print "('e_indent[EI_CLASS]', %d)" % fileclass byteordering = f.read8() if byteordering == 1: # ELFDATA2LSB f.isLSB = True elif byteordering == 2: # ELFDATA2MSB f.isLSB = False else: raise ValueError, "Unknown byte ordering %d" % byteordering print "('e_indent[EI_DATA]', %d)" % byteordering print "('e_indent[EI_VERSION]', %d)" % f.read8() print "('e_indent[EI_OSABI]', %d)" % f.read8() print "('e_indent[EI_ABIVERSION]', %d)" % f.read8() f.seek(16) # Seek to end of e_ident. print "('e_type', %d)" % f.read16() print "('e_machine', %d)" % f.read16() print "('e_version', %d)" % f.read32() print "('e_entry', %d)" % f.readWord() print "('e_phoff', %d)" % f.readWord() e_shoff = f.readWord() print "('e_shoff', %d)" % e_shoff print "('e_flags', %d)" % f.read32() print "('e_ehsize', %d)" % f.read16() print "('e_phentsize', %d)" % f.read16() print "('e_phnum', %d)" % f.read16() e_shentsize = f.read16() print "('e_shentsize', %d)" % e_shentsize e_shnum = f.read16() print "('e_shnum', %d)" % e_shnum e_shstrndx = f.read16() print "('e_shstrndx', %d)" % e_shstrndx # Read all section headers sections = [] for index in range(e_shnum): f.seek(e_shoff + index * e_shentsize) s = Section(f) sections.append(s) # Read .shstrtab so we can resolve section names f.seek(sections[e_shstrndx].sh_offset) shstrtab = StringTable(f.read(sections[e_shstrndx].sh_size)) # Get the symbol string table strtab = None for section in sections: if shstrtab[section.sh_name] == ".strtab": f.seek(section.sh_offset) strtab = StringTable(f.read(section.sh_size)) break print "('_sections', [" for index in range(e_shnum): print " # Section %d" % index sections[index].dump(shstrtab, f, strtab, opts.dumpSectionData) print "])" if __name__ == "__main__": from optparse import OptionParser, OptionGroup parser = OptionParser("usage: %prog [options] {files}") parser.add_option("", "--dump-section-data", dest="dumpSectionData", help="Dump the contents of sections", action="store_true", default=False) (opts, args) = parser.parse_args() if not args: args.append('-') for arg in args: dumpELF(arg, opts)