def restore_pe(file):
from pefile import PE
pe = PE(file,fast_load=True)
# Helpers
find_section = lambda name:next(filter(lambda x:name in x.Name,pe.sections))
find_data_directory = lambda name:next(filter(lambda x:name in x.name,pe.OPTIONAL_HEADER.DATA_DIRECTORY))
# Remove .enigma sections
pe.__data__ = pe.__data__[:find_section(b'.enigma1').PointerToRawData]
pe.FILE_HEADER.NumberOfSections -= 2
# Restore rdata & idata sections
find_data_directory('TLS').VirtualAddress = find_section(b'.rdata').VirtualAddress
find_data_directory('ENTRY_IMPORT').VirtualAddress = find_section(b'.idata').VirtualAddress
# Write to new file
pe_name = os.path.basename(file)[:-4] + ORIGINAL_PE_SUFFIX
pe_name = os.path.join(output,pe_name).replace('\\','/')
pe.write(pe_name)
print('[-] Original PE saved:',pe_name)
def restore_pe(file,output):
# PEfile isn't the best for this job, but we'll get it done ;)
# TODO : Recaluclate SizeOfImage to match the acutal file
from pefile import PE,OPTIONAL_HEADER_MAGIC_PE_PLUS
print('[-] Loading PE...')
pe = PE(file,fast_load=True)
PE64 = pe.PE_TYPE == OPTIONAL_HEADER_MAGIC_PE_PLUS
pe.__data__ = bytearray(pe.__data__) # This allows us to apply slicing on the PE data
# Helpers
find_section = lambda name:next(filter(lambda x:name in x.Name,pe.sections))
find_data_directory = lambda name:next(filter(lambda x:name in x.name,pe.OPTIONAL_HEADER.DATA_DIRECTORY))
# Data
enigma1 = pe.__data__[find_section(b'.enigma1').PointerToRawData:]
hdr = unpack(EVB_ENIGMA1_HEADER,enigma1,104 if PE64 else 76)
# Restore section with built-in offsets. All these ADDRESSes are VAs
find_data_directory('IMPORT').VirtualAddress = hdr['IMPORT_ADDRESS']
find_data_directory('IMPORT').Size = hdr['IMPORT_SIZE']
find_data_directory('RELOC').VirtualAddress = hdr['RELOC_ADDRESS']
find_data_directory('RELOC').Size = hdr['RELOC_SIZE']
print('[-] Rebuilding Exception directory...')
# Rebuild the exception directory
exception_dir = find_data_directory('EXCEPTION')
exception_raw_ptr = pe.get_offset_from_rva(exception_dir.VirtualAddress)
exception_data = pe.__data__[exception_raw_ptr:exception_raw_ptr + exception_dir.Size]
exception_struct = PE64_EXCEPTION if PE64 else PE_EXCEPTION
exception_end = 0
for i in range(0,exception_dir.Size,get_size_by_struct(exception_struct)):
block = unpack(exception_struct,exception_data[i:])
block['section'] = pe.get_section_by_rva(block['BEGIN_ADDRESS'])
exception_end = i
if b'.enigma' in block['section'].Name:
break
exception_data = exception_data[:exception_end]
# Prepare partial TLS data for searching
tls_dir = find_data_directory('TLS')
tls_raw_ptr = pe.get_offset_from_rva(tls_dir.VirtualAddress)
tls_data = bytearray(pe.__data__[tls_raw_ptr:tls_raw_ptr + tls_dir.Size])
original_callback = hdr['TLS_CALLBACK_RVA'] + pe.OPTIONAL_HEADER.ImageBase
original_callback = struct.pack('<' + ('Q' if PE64 else 'I'),original_callback)
if (PE64):
tls_data += original_callback # AddressOfCallBacks
else:
tls_data[12:16] = original_callback # AddressOfCallBacks
tls_data = tls_data[:16]
# Destory .enigma* sections
pe.__data__ = pe.__data__[:find_section(b'.enigma1').PointerToRawData] + pe.__data__[find_section(b'.enigma2').PointerToRawData + find_section(b'.enigma2').SizeOfRawData:]
# If original program has a overlay, this will perserve it. Otherwise it's okay to remove them anyway.
assert pe.sections.pop().Name == b'.enigma2'
assert pe.sections.pop().Name == b'.enigma1'
pe.FILE_HEADER.NumberOfSections -= 2
# NOTE: .enigma1 contains the VFS, as well as some Optional PE Header info as descrbied above
# NOTE: .enigma2 is a aplib compressed loader DLL. You can decompress it with aplib provided in this repo
if (exception_data):
# Reassign the RVA & sizes
print('[-] Rebuilt Exception directory. Size=0x%x' % len(exception_data))
# Find where this could be placed at...since EVB clears the original exception directory listings
# PEs with overlays won't work at all if EVB packed them.
# We must remove the sections and do NOT append anything new
offset = 0
for section in pe.sections:
offset_ = pe.__data__.find(b'\x00' * len(exception_data),section.PointerToRawData, section.PointerToRawData + section.SizeOfRawData)
if offset_ > 0:
# Check for references in the Optional Data Directory
# The offset should not be referenced otherwise we would overwrite existing data
for header in pe.OPTIONAL_HEADER.DATA_DIRECTORY:
if pe.get_rva_from_offset(offset_) in range(header.VirtualAddress,header.VirtualAddress+header.Size):
offset = 0
break
else:
offset = offset_
if offset > 0:
break
assert offset > 0,"Cannot place Exceptions Directory!"
section = pe.get_section_by_rva(pe.get_rva_from_offset(offset))
print('[-] Found suitable section to place Exception Directory. Name=%s RVA=0x%x' % (section.Name.decode(),offset - section.PointerToRawData))
pe.__data__[offset:offset+len(exception_data)] = exception_data
section.SizeOfRawData = max(section.SizeOfRawData,len(exception_data))
exception_dir.VirtualAddress = pe.get_rva_from_offset(offset)
exception_dir.Size = len(exception_data)
else:
print('[-] Original program does not contain Exception Directory.')
exception_dir.VirtualAddress = 0
exception_dir.Size = 0
offset = pe.__data__.find(tls_data)
# Append the exception section and assign the pointers
# Serach for TLS in memory map since it's not removed.
tls_dir = find_data_directory('TLS')
if (offset > 0):
print('[-] TLS Directory found. Offset=0x%x' % offset)
tls_dir.VirtualAddress = pe.get_rva_from_offset(offset)
tls_dir.Size = 40 if PE64 else 24
else:
print('[-] Original program does not utilize TLS.')
tls_dir.VirtualAddress = 0
tls_dir.Size = 0
# Write to new file
pe_name = os.path.basename(file)[:-4] + ORIGINAL_PE_SUFFIX
pe_name = os.path.join(output,pe_name).replace('\\','/')
new_file_data = pe.write()
write_bytes(BytesIO(new_file_data),open(pe_name,'wb+'),len(new_file_data),desc='Saving PE')
print('[-] Original PE saved:',pe_name)
