def parse(self):
try:
self.data = uf2.Uf2.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
check_condition(self.data.uf2_block_start.block_number == 0,
'invalid start block')
def parse(self):
try:
self.data = kaitai_snappy.Snappy.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
# first chunk has to be the header, even though
# this is already covered by the signature
check_condition(
self.data.chunks[0].identifier ==
kaitai_snappy.Snappy.ChunkTypes.stream_identifier,
"invalid first chunk")
seen_frame_identifier = False
self.unpacked_size = 0
for chunk in self.data.chunks:
if chunk.is_valid:
# check to see if there possibly is more than one stream
# if so decompress them separately
if chunk.identifier == kaitai_snappy.Snappy.ChunkTypes.stream_identifier:
if not seen_frame_identifier:
seen_frame_identifier = True
else:
break
self.unpacked_size += 4 + chunk.body.len_chunk.value
def calculate_unpacked_size(self):
# According to https://web.archive.org/web/20080321063028/http://technet2.microsoft.com/windowsserver/en/library/bdeda920-1f08-4683-9ffb-7b4b50df0b5a1033.mspx?mfr=true
# the backup GPT header is at the last sector of the disk
#
# There are situations, such as on some Android devices , where the
# GPT partition table and the actual partitions are separate from eachother
# and where the LBA of the backup GPT is 0.
#
# There are also situations where the partition table is completely
# unreliable, for example Android devices where certain partitions have
# been removed from the firmware update, but where the partition table
# has not been changed.
try:
self.unpacked_size = (self.data.primary.backup_lba +
1) * self.data.sector_size
except BaseException as e:
print("EXC")
raise UnpackParserException(e.args)
all_entries_size = self.data.primary.entries_size * self.data.primary.entries_count
self.unpacked_size = max(
self.unpacked_size,
self.data.primary.entries_start * self.data.sector_size +
all_entries_size)
for e in self.data.primary.entries:
partition_start = e.first_lba * self.data.sector_size
partition_end = (e.last_lba + 1) * self.data.sector_size
if partition_start + partition_end > self.fileresult.filesize:
continue
check_condition(self.unpacked_size <= self.fileresult.filesize,
"partition bigger than file")
def parse(self):
# For reasons unknown pyOpenSSL sometimes barfs on certs from
# Android, so use an external tool (for now).
check_condition(
shutil.which('openssl') is not None, "openssl program not found")
buf = self.infile.read(80)
self.certtype = None
if b'PRIVATE KEY' in buf:
self.certtype = 'key'
elif b'CERTIFICATE' in buf:
self.certtype = 'certificate'
# try to find the end of the certificate
end_pos = -1
self.infile.seek(0)
self.pos = self.infile.tell()
cert_unpacked = False
while True:
buf = self.infile.read(2048)
if buf == b'':
break
end_pos = buf.find(b'-----END')
if end_pos != -1:
if self.certtype == 'key':
end_res = buf.find(b'KEY-----', end_pos)
if end_res != -1:
end_of_certificate = self.pos + end_res + 8
cert_unpacked = True
elif self.certtype == 'certificate':
end_res = buf.find(b'CERTIFICATE-----', end_pos)
if end_res != -1:
end_of_certificate = self.pos + end_res + 16
cert_unpacked = True
else:
end_res = buf.find(b'-----', end_pos + 1)
if end_res != -1:
end_of_certificate = self.pos + end_res + 5
cert_unpacked = True
break
# make sure there is a little bit of overlap
if self.infile.tell() + self.offset == self.fileresult.filesize:
break
self.infile.seek(-15, os.SEEK_CUR)
self.pos = self.infile.tell()
check_condition(end_pos != -1, "no end of certificate found")
check_condition(cert_unpacked, "no certificate found")
# check the certificate
self.infile.seek(0)
cert = self.infile.read(end_of_certificate)
check_condition(
list(filter(lambda x: chr(x) not in string.printable, cert)) == [],
"text cert can only contain ASCII printable characters")
(res, self.cert_labels) = self.extract_certificate(cert)
check_condition(res, "not a valid certificate")
def unpack(self):
unpacked_files = []
out_labels = []
unpackdir_full = self.scan_environment.unpack_path(self.rel_unpack_dir)
p = subprocess.Popen([
'ar', 'x', self.fileresult.filename,
'--output=%s' % unpackdir_full
],
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
(outputmsg, errormsg) = p.communicate()
# TODO: look into cleanup if unpacking fails, is it necessary?
check_condition(p.returncode == 0, "Not a valid ar file")
# walk the results directory
for result in unpackdir_full.glob('**/*'):
# first change the permissions
result.chmod(stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR)
# then add the file to the result set
file_path = result.relative_to(unpackdir_full)
fr = FileResult(self.fileresult, self.rel_unpack_dir / file_path,
set())
unpacked_files.append(fr)
return unpacked_files
def parse(self):
check_condition(False, "unsupported")
check_condition(
shutil.which('unpack200') is not None, "pack200 program not found")
# create a temporary directory
temp_dir = tempfile.mkdtemp(
dir=self.scan_environment.temporarydirectory)
# the unpack200 tool only works on whole files. Finding out
# where the file ends is TODO, but if there is data in front
# of a valid pack200 file it is not a problem.
havetmpfile = False
if self.offset != 0:
pass
if havetmpfile:
p = subprocess.Popen(['unpack200', temporaryfile[1], outfile_full],
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
cwd=temp_dir)
else:
p = subprocess.Popen(
['unpack200', self.fileresult.filename, outfile_full],
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
cwd=temp_dir)
(outputmsg, errormsg) = p.communicate()
if havetmpfile:
os.unlink(temporary_file[1])
def parse(self):
try:
self.data = doom_wad.DoomWad.from_io(self.infile)
# TODO: decide what exceptions to catch
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
except BaseException as e:
raise UnpackParserException(e.args)
# this is a bit of an ugly hack to detect if the file has been
# truncated or corrupted. In certain cases (like when scanning the
# 'magic' database) it could be that the offset would be bigger
# than the file itself and there would be hundreds of millions of
# index entries for which the generated code would first try to create
# an IndexEntry() object leading to an out of memory issue.
filesize = self.fileresult.filesize
check_condition(self.data.index_offset <= filesize,
"index offset outside of file")
check_condition(self.data.num_index_entries > 0, "no lumps defined")
# another ugly hack to prevent ASCII decoding errors
# (example: when scanning mime.cache)
try:
for i in self.data.index:
pass
except Exception as e:
raise UnpackParserException(e.args)
def parse(self):
# needs LZ77 decompression
check_condition(False, "unsupported")
try:
self.data = novatek.Novatek.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
def parse(self):
self.file_size = self.fileresult.filesize
try:
self.data = llvm_ir_wrapper.LlvmIrWrapper.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
self.unpacked_size = self.data.ofs_bytecode + self.data.len_bytecode
check_condition(self.file_size >= self.unpacked_size,
"not enough data")
def parse(self):
self.unpacked_size = 0
try:
self.data = android_imgdata.AndroidImgdata.from_io(self.infile)
for image in self.data.images:
self.unpacked_size = max(self.unpacked_size, image.ofs_image + image.len_image)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
check_condition(self.unpacked_size <= self.fileresult.filesize, "data outside file")
def parse(self):
try:
self.data = dhtb.Dhtb.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
sha256 = hashlib.sha256(self.data.payload)
check_condition(
sha256.hexdigest() == binascii.hexlify(
self.data.header.sha256).decode(), 'invalid hash')
def parse(self):
try:
self.data = trx.Trx.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
computed_crc = ~zlib.crc32(self.data.raw_data) & 0xffffffff
check_condition(self.data.preheader.crc32 == computed_crc,
"invalid CRC32")
def parse(self):
try:
self.data = xg3d.Xg3d.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
check_condition(
self.offset == 0
and self.infile.tell() == self.fileresult.filesize,
"carving not supported for xg3d")
def calculate_unpacked_size(self):
self.unpacked_size = 0
for p in self.data.partitions:
self.unpacked_size = max(self.unpacked_size,
(p.lba_start + p.num_sectors) * 512)
check_condition(self.unpacked_size <= self.fileresult.filesize,
"partition bigger than file")
check_condition(self.unpacked_size >= 0x1be,
"invalid partition table: no partitions")
def parse(self):
file_size = self.fileresult.filesize
self.is_variant = False
try:
self.data = android_img.AndroidImg.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
try:
self.infile.seek(self.offset)
self.data = android_img_lk.AndroidImgLk.from_io(self.infile)
self.is_variant = True
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
self.unpacked_size = self.infile.tell()
# compute the size and check against the file size
# take padding into account
if self.is_variant:
self.unpacked_size = max(
self.unpacked_size,
self.data.header.dtb_pos + self.data.header.dt_size)
else:
if self.data.header_version < 3:
page_size = self.data.header.page_size
try:
unpacked_size = (
(page_size + self.data.header.kernel.size + page_size -
1) // page_size) * page_size
except ZeroDivisionError as e:
raise UnpackParserException(e.args)
if self.data.header.ramdisk.size > 0:
unpacked_size = (
(unpacked_size + self.data.header.ramdisk.size +
page_size - 1) // page_size) * page_size
if self.data.header.second.size > 0:
unpacked_size = (
(unpacked_size + self.data.header.second.size +
page_size - 1) // page_size) * page_size
if self.data.header_version > 0:
if self.data.header.recovery_dtbo.size > 0:
unpacked_size = (
(self.data.header.recovery_dtbo.offset +
self.data.header.recovery_dtbo.size + page_size -
1) // page_size) * page_size
if self.data.header_version > 1:
if self.data.header.dtb.size > 0:
unpacked_size = (
(unpacked_size + self.data.header.dtb.size +
page_size - 1) // page_size) * page_size
self.unpacked_size = max(self.unpacked_size, unpacked_size)
check_condition(file_size >= self.unpacked_size,
"not enough data")
elif self.data.header_version in [3, 4]:
unpacked_size = 4096 + len(self.data.header.kernel_img) + \
len(self.data.header.padding1) + len(self.data.header.ramdisk_img) + \
len(self.data.header.padding2)
self.unpacked_size = max(self.unpacked_size, unpacked_size)
def parse(self):
try:
self.data = gif.Gif.from_io(self.infile)
except Exception as e:
raise UnpackParserException(e.args)
check_condition(self.data.logical_screen_descriptor.screen_width > 0,
"invalid width")
check_condition(self.data.logical_screen_descriptor.screen_height > 0,
"invalid height")
def calculate_unpacked_size(self):
# According to https://web.archive.org/web/20080321063028/http://technet2.microsoft.com/windowsserver/en/library/bdeda920-1f08-4683-9ffb-7b4b50df0b5a1033.mspx?mfr=true
# the backup GPT header is at the last sector of the disk
try:
self.unpacked_size = (self.data.primary.backup_lba +
1) * self.data.sector_size
except Exception as e:
raise UnpackParserException(e.args)
check_condition(self.unpacked_size <= self.fileresult.filesize,
"partition bigger than file")
def parse(self):
file_size = self.fileresult.filename.stat().st_size
try:
self.data = android_msm_bootldr.AndroidMsmBootldr.from_io(self.infile)
except (Exception, ValidationNotEqualError) as e:
raise UnpackParserException(e.args)
self.unpacked_size = self.data.ofs_start
for entry in self.data.img_info:
self.unpacked_size += entry.size
check_condition(file_size >= self.unpacked_size, "not enough data")
def calculate_unpacked_size(self):
self.unpacked_size = 0
try:
for p in self.data.partitions:
self.unpacked_size = max(self.unpacked_size,
(p.lba_start + p.num_sectors) * 512)
except BaseException as e:
raise UnpackParserException(e.args)
check_condition(self.unpacked_size >= 0x1be,
"invalid partition table: no partitions")
def parse(self):
resource_ids = set()
try:
self.data = chrome_pak.ChromePak.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
check_condition(self.data.resources[-1].id == 0,
"wrong resource identifier")
check_condition(
self.data.resources[-1].ofs_body <= self.fileresult.filesize,
"not enough data")
def parse(self):
try:
self.data = dds.Dds.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
compatible_flags = True
if self.data.dds_header.flags & 0x8 == 0x8 and self.data.dds_header.flags & 0x80000 == 0x80000:
compatible_flags = False
check_condition(compatible_flags, "incompatible flags specified")
check_condition(self.data.dds_header.flags & 0x80000 == 0x80000,
"uncompressed files currently not supported")
def parse(self):
file_size = self.fileresult.filesize
try:
self.data = android_bootldr_qcom.AndroidBootldrQcom.from_io(
self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
self.unpacked_size = self.data.ofs_img_bodies
for entry in self.data.img_headers:
self.unpacked_size += entry.len_body
check_condition(file_size >= self.unpacked_size, "not enough data")
def parse(self):
self.file_size = self.fileresult.filesize
try:
self.data = au.Au.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
check_condition(self.data.header.data_size != 0xffffffff,
"files with unknown data size not supported")
check_condition(
self.file_size >= self.data.ofs_data + self.data.header.data_size,
"not enough data")
def parse(self):
try:
self.data = pcapng.Pcapng.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
section_header_seen = False
for block in self.data.blocks:
if block.header_type == pcapng.Pcapng.HeaderTypes.section_header:
section_header_seen = True
break
check_condition(section_header_seen, "no section header block found")
def parse(self):
try:
self.data = pcf_font.PcfFont.from_io(self.infile)
check_condition(self.data.num_tables > 0,
"invalid number of tables")
# this is a bit of an ugly hack to detect if the file
# has been truncated.
for i in self.data.tables:
a = type(i.body)
except (Exception, ValidationNotEqualError) as e:
raise UnpackParserException(e.args)
def parse(self):
file_size = self.fileresult.filesize
try:
self.data = mozilla_mar.MozillaMar.from_io(self.infile)
except (Exception, ValidationNotEqualError) as e:
raise UnpackParserException(e.args)
except EOFError as e:
raise UnpackParserException(e.args)
check_condition(
self.data.file_size == self.data.ofs_index + 4 +
self.data.index.len_index, "Wrong file size")
check_condition(self.data.file_size <= file_size, "Not enough data")
def parse(self):
resource_ids = set()
try:
self.data = chrome_pak.ChromePak.from_io(self.infile)
except (Exception, ValidationNotEqualError,
ValidationGreaterThanError) as e:
raise UnpackParserException(e.args)
check_condition(self.data.header.resources[-1].id == 0,
"wrong resource identifier")
check_condition(
self.data.header.resources[-1].offset <= self.fileresult.filesize,
"not enough data")
def parse(self):
try:
self.data = apple_single_double.AppleSingleDouble.from_io(
self.infile)
# this is a bit of an ugly hack as the Kaitai parser is
# not entirely complete. Use this to detect if the file
# has been truncated.
for i in self.data.entries:
a = type(i.body)
except (Exception, ValidationNotEqualError) as e:
raise UnpackParserException(e.args)
check_condition(self.data.num_entries > 1, "no apple double entries")
def parse(self):
try:
self.data = kaitai_lz4.Lz4.from_io(self.infile)
except (Exception, ValidationFailedError) as e:
raise UnpackParserException(e.args)
for block in self.data.blocks:
if block.is_endmark:
break
if self.data.frame_descriptor.flag.block_checksum:
block_checksum = xxhash.xxh32(block.data)
check_condition(block.checksum == block_checksum.intdigest(),
"invalid block checksum")
def parse(self):
try:
self.data = gif.Gif.from_io(self.infile)
# TODO: decide what exceptions to catch
except (Exception, ValidationNotEqualError) as e:
raise UnpackParserException(e.args)
except BaseException as e:
raise UnpackParserException(e.args)
check_condition(self.data.logical_screen_descriptor.screen_width > 0,
"invalid width")
check_condition(self.data.logical_screen_descriptor.screen_height > 0,
"invalid height")
