def getSectionList(self):
nullSh = Sh()
nullSh.retrieve([0x00 for i in range(56)])
nullSection = Section([], '', nullSh)
strSection = self.makeShStrSection()
return (nullSection, self.sectionList, strSection)
def extract(self):
shSize = self.eh.get('sh_size')
shNum = self.eh.get('sh_num')
shOff = self.eh.get('sh_offset')
strTab = self.retrieveStringTable()
result = []
for idx in range(1, shNum):
if idx == self.eh.get('shstrndx'):
continue
shStart = shOff + shSize * idx
sh = Sh()
sh.retrieve(self.byteList[shStart:shStart+shSize])
name = retrieveStr(strTab, sh.get('name_index'))
body = self.byteList[sh.get('offset'):sh.get('offset')+sh.get('size')]
if name == '.symtab' or name == '.strtab':
continue
result.append((name, body, sh))
return result
def makeShStrSection(self, offset):
shStr = "\0"
for h in self.sectionList:
h['sh'].set('name_index', len(shStr))
shStr += h['name'] + "\0"
shStrIdx = len(shStr)
shStr += ".shstrtab\0"
shStrTab = map(ord, shStr)
shList = []
shList += convLE(shStrIdx, 4) # name_index
shList += convLE(3, 4) # type
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # flag
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # address
shList += convLE(offset, 8) # offset(dummy)
shList += convLE(len(shStr), 8) # size
shList += [0x00, 0x00, 0x00, 0x00] # link
shList += [0x00, 0x00, 0x00, 0x00] # info
shList += convLE(1, 8) # address_align
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00] # entry_table_size
sh = Sh().retrieve(shList)
self.append('.shstrtab', shStrTab, sh)
return shStrTab
def makeShStrSection(self):
shStr = "\0"
for s in self.sectionList:
sh = s.getSh()
sh.set('name_index', len(shStr))
shStr += s.getName() + "\0"
shStrIdx = len(shStr)
shStr += ".shstrtab\0"
shStrTab = map(ord, shStr)
shList = []
shList += convLE(shStrIdx, 4) # name_index
shList += convLE(3, 4) # type
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # flag
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # address
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # offset
shList += convLE(len(shStr), 8) # size
shList += [0x00, 0x00, 0x00, 0x00] # link
shList += [0x00, 0x00, 0x00, 0x00] # info
shList += convLE(1, 0) # address_align
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # entry_table_size
sh = Sh().retrieve(shList)
return Section(shStrTab, '.shstrtab', sh)
def setShStrTab(self, shStr):
shStrTab = map(ord, shStr)
for (i, s) in enumerate(self.sectionList):
if s.getName() == '.shstrtab':
s.setBodyList(shStrTab)
return True
# if .shstrtab isn't exits then make it
shStrList = shStr.split("\0")
shList = []
shList += convLE(shStrList.index('.shstrtab'), 4) # name_index
shList += convLE(3, 4) # type
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # flag
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # address
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # offset
shList += convLE(len(shStr), 8) # size
shList += [0x00, 0x00, 0x00, 0x00] # link
shList += [0x00, 0x00, 0x00, 0x00] # info
shList += convLE(1, 0) # address_align
shList += [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] # entry_table_size
sh = Sh().retrieve(shList)
self.sectionList.append(Section(shStrTab, '.shstrtab', sh))
def retrieveStringTable(self):
shSize = self.eh.get('sh_size')
shNum = self.eh.get('sh_num')
shOff = self.eh.get('sh_offset')
# get string table section header start position
shStrStart = shOff + shSize * self.eh.get('shstrndx')
strSh = Sh()
strSh.retrieve(self.byteList[shStrStart:shStrStart+shSize])
strOff = strSh.get('offset')
strSize = strSh.get('size')
strTab = ''.join(map(chr, self.byteList[strOff:strOff+strSize]))
return strTab
# teardown ELF file
f = open('test.out')
byteList = map(lambda x: int(ord(x)), f.read())
# get ELF header
eh = Eh()
eh.retrieve(byteList[0:64])
shSize = eh.get('sh_size')
shNum = eh.get('sh_num')
shOff = eh.get('sh_offset')
# get sh string table
shStrStart = shOff + shSize * eh.get('shstrndx')
strSh = Sh()
strSh.retrieve(byteList[shStrStart:shStrStart+shSize])
strOff = strSh.get('offset')
strSize= strSh.get('size')
strTab = ''.join(map(chr, byteList[strOff:strOff+strSize]))
# get sections
secAggr = SectionAggregator()
for idx in range(1, shNum):
if idx == eh.get('shstrndx'):
continue
shStart = shOff + shSize * idx
import sys
from elf.components.headers.Sh import Sh
from elf.components.SectionController import SectionController
from elf.components.SegmentController import SegmentController
from elf.components.Section import Section
from elf.WriteElf import WriteElf
from elf.Utils import *
sctCtrl = SectionController()
#.text header
name = '.text'
byteList = [0xb8, 0x3c, 0x00, 0x00, 0x00]
byteList += [0xbf, 0x2a, 0x00, 0x00, 0x00]
byteList += [0x0f, 0x05]
sh = Sh()
sh.set('type', 1)
sh.set('flag', 6)
sh.set('size', len(byteList))
sh.set('address_align', 1)
sh.set('entry_table_size', 0)
sctCtrl.append(Section(byteList, name, sh))
# dummy for test
#name = '.interp'
#byteList = [0xb8, 0x3c, 0x00, 0x00, 0x00]
#byteList += [0xbf, 0x2a, 0x00, 0x00, 0x00]
#byteList += [0x0f, 0x05]
#sh = Sh()
#sh.set('type', 3)
#sh.set('flag', 6)
