def __init__(self, database): """Reader for the MaxMind DB file format Arguments: database -- A path to a valid MaxMind DB file such as a GeoIP2 database file. """ with open(database, 'rb') as db_file: self._buffer = mmap.mmap( db_file.fileno(), 0, access=mmap.ACCESS_READ) metadata_start = self._buffer.rfind(self._METADATA_START_MARKER, self._buffer.size() - 128 * 1024) if metadata_start == -1: raise InvalidDatabaseError('Error opening database file ({0}). ' 'Is this a valid MaxMind DB file?' ''.format(database)) metadata_start += len(self._METADATA_START_MARKER) metadata_decoder = Decoder(self._buffer, metadata_start) (metadata, _) = metadata_decoder.decode(metadata_start) self._metadata = Metadata(**metadata) # pylint: disable=star-args self._decoder = Decoder(self._buffer, self._metadata.search_tree_size + self._DATA_SECTION_SEPARATOR_SIZE)
def __init__(self, database, mode=MODE_AUTO): """Reader for the MaxMind DB file format Arguments: database -- A path to a valid MaxMind DB file such as a GeoIP2 database file, or a file descriptor in the case of MODE_FD. mode -- mode to open the database with. Valid mode are: * MODE_MMAP - read from memory map. * MODE_FILE - read database as standard file. * MODE_MEMORY - load database into memory. * MODE_AUTO - tries MODE_MMAP and then MODE_FILE. Default. * MODE_FD - the param passed via database is a file descriptor, not a path. This mode implies MODE_MEMORY. """ if (mode == MODE_AUTO and mmap) or mode == MODE_MMAP: with open(database, 'rb') as db_file: self._buffer = mmap.mmap(db_file.fileno(), 0, access=mmap.ACCESS_READ) self._buffer_size = self._buffer.size() filename = database elif mode in (MODE_AUTO, MODE_FILE): self._buffer = FileBuffer(database) self._buffer_size = self._buffer.size() filename = database elif mode == MODE_MEMORY: with open(database, 'rb') as db_file: self._buffer = db_file.read() self._buffer_size = len(self._buffer) filename = database elif mode == MODE_FD: self._buffer = database.read() self._buffer_size = len(self._buffer) filename = database.name else: raise ValueError( 'Unsupported open mode ({0}). Only MODE_AUTO, MODE_FILE, ' 'MODE_MEMORY and MODE_FD are supported by the pure Python ' 'Reader'.format(mode)) metadata_start = self._buffer.rfind( self._METADATA_START_MARKER, max(0, self._buffer_size - 128 * 1024)) if metadata_start == -1: self.close() raise InvalidDatabaseError('Error opening database file ({0}). ' 'Is this a valid MaxMind DB file?' ''.format(filename)) metadata_start += len(self._METADATA_START_MARKER) metadata_decoder = Decoder(self._buffer, metadata_start) (metadata, _) = metadata_decoder.decode(metadata_start) self._metadata = Metadata(**metadata) # pylint: disable=bad-option-value self._decoder = Decoder( self._buffer, self._metadata.search_tree_size + self._DATA_SECTION_SEPARATOR_SIZE) self.closed = False
def _resolve_data_pointer(self, pointer): resolved = pointer - self._metadata.node_count + self._metadata.search_tree_size if resolved >= self._buffer_size: raise InvalidDatabaseError("The MaxMind DB file's search tree is corrupt") (data, _) = self._decoder.decode(resolved) return data
def _read_extended(self, offset: int) -> Tuple[int, int]: next_byte = self._buffer[offset] type_num = next_byte + 7 if type_num < 7: raise InvalidDatabaseError( "Something went horribly wrong in the decoder. An " f"extended type resolved to a type number < 8 ({type_num})") return type_num, offset + 1
def _read_extended(self, offset): (next_byte, ) = struct.unpack(b'!B', self._buffer[offset:offset + 1]) type_num = next_byte + 7 if type_num < 7: raise InvalidDatabaseError( 'Something went horribly wrong in the decoder. An ' 'extended type resolved to a type number < 8 ' '({type})'.format(type=type_num)) return type_num, offset + 1
def _read_extended(self, offset): next_byte = int_from_byte(self._buffer[offset]) type_num = next_byte + 7 if type_num < 7: raise InvalidDatabaseError( 'Something went horribly wrong in the decoder. An ' 'extended type resolved to a type number < 8 ' '({type})'.format(type=type_num)) return type_num, offset + 1
def _find_address_in_tree(self, packed: bytearray) -> Tuple[int, int]: bit_count = len(packed) * 8 node = self._start_node(bit_count) node_count = self._metadata.node_count i = 0 while i < bit_count and node < node_count: bit = 1 & (packed[i >> 3] >> 7 - (i % 8)) node = self._read_node(node, bit) i = i + 1 if node == node_count: # Record is empty return 0, i if node > node_count: return node, i raise InvalidDatabaseError("Invalid node in search tree")
def _find_address_in_tree(self, ip_address): packed = bytearray(ip_address.packed) bit_count = len(packed) * 8 node = self._start_node(bit_count) for i in range(bit_count): if node >= self._metadata.node_count: break bit = 1 & (packed[i >> 3] >> 7 - (i % 8)) node = self._read_node(node, bit) if node == self._metadata.node_count: # Record is empty return 0 elif node > self._metadata.node_count: return node raise InvalidDatabaseError('Invalid node in search tree')
def decode(self, offset): """Decode a section of the data section starting at offset Arguments: offset -- the location of the data structure to decode """ new_offset = offset + 1 (ctrl_byte, ) = struct.unpack(b'!B', self._buffer[offset:new_offset]) type_num = ctrl_byte >> 5 # Extended type if not type_num: (type_num, new_offset) = self._read_extended(new_offset) if type_num not in self._type_decoder: raise InvalidDatabaseError('Unexpected type number ({type}) ' 'encountered'.format(type=type_num)) (size, new_offset) = self._size_from_ctrl_byte(ctrl_byte, new_offset, type_num) return self._type_decoder[type_num](self, size, new_offset)
def _read_node(self, node_number, index): base_offset = node_number * self._metadata.node_byte_size record_size = self._metadata.record_size if record_size == 24: offset = base_offset + index * 3 node_bytes = b"\x00" + self._buffer[offset : offset + 3] elif record_size == 28: offset = base_offset + 3 * index node_bytes = bytearray(self._buffer[offset : offset + 4]) if index: node_bytes[0] = 0x0F & node_bytes[0] else: middle = (0xF0 & node_bytes.pop()) >> 4 node_bytes.insert(0, middle) elif record_size == 32: offset = base_offset + index * 4 node_bytes = self._buffer[offset : offset + 4] else: raise InvalidDatabaseError("Unknown record size: {0}".format(record_size)) return struct.unpack(b"!I", node_bytes)[0]
def decode(self, offset: int) -> Tuple[Record, int]: """Decode a section of the data section starting at offset Arguments: offset -- the location of the data structure to decode """ new_offset = offset + 1 ctrl_byte = self._buffer[offset] type_num = ctrl_byte >> 5 # Extended type if not type_num: (type_num, new_offset) = self._read_extended(new_offset) try: decoder = self._type_decoder[type_num] except KeyError as ex: raise InvalidDatabaseError( f"Unexpected type number ({type_num}) encountered") from ex (size, new_offset) = self._size_from_ctrl_byte(ctrl_byte, new_offset, type_num) return decoder(self, size, new_offset)
def decode(self, offset): """Decode a section of the data section starting at offset Arguments: offset -- the location of the data structure to decode """ new_offset = offset + 1 ctrl_byte = int_from_byte(self._buffer[offset]) type_num = ctrl_byte >> 5 # Extended type if not type_num: (type_num, new_offset) = self._read_extended(new_offset) try: decoder = self._type_decoder[type_num] except KeyError: raise InvalidDatabaseError("Unexpected type number ({type}) " "encountered".format(type=type_num)) (size, new_offset) = self._size_from_ctrl_byte(ctrl_byte, new_offset, type_num) return decoder(self, size, new_offset)
def _read_node(self, node_number, index): base_offset = node_number * self._metadata.node_byte_size record_size = self._metadata.record_size if record_size == 24: offset = base_offset + index * 3 node_bytes = b'\x00' + self._buffer[offset:offset + 3] elif record_size == 28: (middle, ) = struct.unpack( b'!B', self._buffer[base_offset + 3:base_offset + 4]) if index: middle &= 0x0F else: middle = (0xF0 & middle) >> 4 offset = base_offset + index * 4 node_bytes = byte_from_int(middle) + self._buffer[offset:offset + 3] elif record_size == 32: offset = base_offset + index * 4 node_bytes = self._buffer[offset:offset + 4] else: raise InvalidDatabaseError( 'Unknown record size: {0}'.format(record_size)) return struct.unpack(b'!I', node_bytes)[0]
def _verify_size(self, expected, actual): if expected != actual: raise InvalidDatabaseError( 'The MaxMind DB file\'s data section contains bad data ' '(unknown data type or corrupt data)')
def __init__(self, database: Union[AnyStr, int, PathLike, IO], mode: int = MODE_AUTO) -> None: """Reader for the MaxMind DB file format Arguments: database -- A path to a valid MaxMind DB file such as a GeoIP2 database file, or a file descriptor in the case of MODE_FD. mode -- mode to open the database with. Valid mode are: * MODE_MMAP - read from memory map. * MODE_FILE - read database as standard file. * MODE_MEMORY - load database into memory. * MODE_AUTO - tries MODE_MMAP and then MODE_FILE. Default. * MODE_FD - the param passed via database is a file descriptor, not a path. This mode implies MODE_MEMORY. """ filename: Any if (mode == MODE_AUTO and mmap) or mode == MODE_MMAP: with open(database, "rb") as db_file: # type: ignore self._buffer = mmap.mmap(db_file.fileno(), 0, access=mmap.ACCESS_READ) self._buffer_size = self._buffer.size() filename = database elif mode in (MODE_AUTO, MODE_FILE): self._buffer = FileBuffer(database) # type: ignore self._buffer_size = self._buffer.size() filename = database elif mode == MODE_MEMORY: with open(database, "rb") as db_file: # type: ignore self._buffer = db_file.read() self._buffer_size = len(self._buffer) filename = database elif mode == MODE_FD: self._buffer = database.read() # type: ignore self._buffer_size = len(self._buffer) # type: ignore filename = database.name # type: ignore else: raise ValueError( f"Unsupported open mode ({mode}). Only MODE_AUTO, MODE_FILE, " "MODE_MEMORY and MODE_FD are supported by the pure Python " "Reader") metadata_start = self._buffer.rfind( self._METADATA_START_MARKER, max(0, self._buffer_size - 128 * 1024)) if metadata_start == -1: self.close() raise InvalidDatabaseError( f"Error opening database file ({filename}). " "Is this a valid MaxMind DB file?") metadata_start += len(self._METADATA_START_MARKER) metadata_decoder = Decoder(self._buffer, metadata_start) (metadata, _) = metadata_decoder.decode(metadata_start) if not isinstance(metadata, dict): raise InvalidDatabaseError( f"Error reading metadata in database file ({filename}).") self._metadata = Metadata(**metadata) # pylint: disable=bad-option-value self._decoder = Decoder( self._buffer, self._metadata.search_tree_size + self._DATA_SECTION_SEPARATOR_SIZE, ) self.closed = False
def _verify_size(expected: int, actual: int) -> None: if expected != actual: raise InvalidDatabaseError( "The MaxMind DB file's data section contains bad data " "(unknown data type or corrupt data)")