# firmware_description.py
# Contains the class that represent a Scrutiny Firmware Description file.
# A .sfd is a file that holds all the data related to a firmware and is identified
# by a unique ID.
#
# - License : MIT - See LICENSE file.
# - Project : Scrutiny Debugger (github.com/scrutinydebugger/scrutiny-python)
#
# Copyright (c) 2021 Scrutiny Debugger
__all__ = ['SFDGenerationInfo', 'SFDMetadata', 'FirmwareDescription', 'GenerationInfoTypedDict', 'MetadataTypedDict']
import zipfile
import os
import json
import logging
from datetime import datetime
from dataclasses import dataclass
import scrutiny.core.firmware_id as firmware_id
from scrutiny.core.varmap import VarMap
from scrutiny.core.variable import Variable
from scrutiny.server.datastore.datastore import Datastore
from scrutiny.core.basic_types import WatchableType
from scrutiny.core.alias import Alias
from scrutiny.core.basic_types import *
from scrutiny.tools.typing import *
from scrutiny.tools import validation
class GenerationInfoTypedDict(TypedDict, total=False):
"""
Metadata about the environment of the file creator
"""
time: Optional[int]
python_version: Optional[str]
scrutiny_version: Optional[str]
system_type: Optional[str]
class MetadataTypedDict(TypedDict, total=False):
"""
Firmware Description metadata. Used for display in the UI (Communicated through API)
"""
project_name: Optional[str]
author: Optional[str]
version: Optional[str]
generation_info: Optional[GenerationInfoTypedDict]
[docs]
@dataclass(frozen=True)
class SFDGenerationInfo:
"""(Immutable struct) Metadata relative to the generation of the SFD"""
timestamp: Optional[datetime]
"""Date/time at which the SFD has been created ``None`` if not available"""
python_version: Optional[str]
"""Python version with which the SFD has been created ``None`` if not available"""
scrutiny_version: Optional[str]
"""Scrutiny version with which the SFD has been created ``None`` if not available"""
system_type: Optional[str]
"""Type of system on which the SFD has been created. Value given by Python `platform.system()`. ``None`` if not available"""
def __post_init__(self) -> None:
validation.assert_type_or_none(self.timestamp, 'timestamp', datetime)
validation.assert_type_or_none(self.python_version, 'python_version', str)
validation.assert_type_or_none(self.scrutiny_version, 'scrutiny_version', str)
validation.assert_type_or_none(self.system_type, 'system_type', str)
def to_dict(self) -> GenerationInfoTypedDict:
timestmap = None
if self.timestamp is not None:
timestamp = int(self.timestamp.timestamp())
return {
'python_version' : self.python_version,
'scrutiny_version' : self.scrutiny_version,
'system_type' : self.system_type,
'time' : timestamp
}
class FirmwareDescription:
"""
Scrutiny Firmware Description (SFD) is an object that contains all the relevant data about a firmware.
It mainly knows its firmware ID and the list of variables with their location.
Upon connection with a device, the correct SFD must be loaded, found with the firmware ID
"""
COMPRESSION_TYPE = zipfile.ZIP_DEFLATED
varmap: VarMap
metadata: SFDMetadata
firmwareid: bytes
aliases: Dict[str, Alias]
varmap_filename: str = 'varmap.json'
metadata_filename: str = 'metadata.json'
firmwareid_filename: str = 'firmwareid'
alias_file: str = 'alias.json'
logger = logging.getLogger('FirmwareDescription')
REQUIRED_FILES: List[str] = [
firmwareid_filename,
metadata_filename,
varmap_filename
]
def __init__(self, file_folder: str):
if os.path.isdir(file_folder):
self.load_from_folder(file_folder)
elif os.path.isfile(file_folder):
self.load_from_file(file_folder)
self.validate()
def load_from_folder(self, folder: str) -> None:
"""
Reads a folder just like if it was an unzipped Scrutiny Firmware Description (SFD) file.
Used to build the SFD
"""
if not os.path.isdir(folder):
raise Exception("Folder %s does not exist" % folder)
for file in self.REQUIRED_FILES:
if not os.path.isfile(os.path.join(folder, file)):
raise Exception('Missing %s' % file)
metadata_file = os.path.join(folder, self.metadata_filename)
with open(metadata_file, 'rb') as f:
self.metadata = self.read_metadata(f)
with open(os.path.join(folder, self.firmwareid_filename), 'rb') as f:
self.firmwareid = self.read_firmware_id(f)
self.varmap = self.read_varmap_from_filesystem(folder)
self.aliases = {}
if os.path.isfile(os.path.join(folder, self.alias_file)):
with open(os.path.join(folder, self.alias_file), 'rb') as f:
aliases = self.read_aliases(f, self.varmap)
self.append_aliases(aliases)
@classmethod
def read_metadata_from_sfd_file(cls, filename: str) -> SFDMetadata:
with zipfile.ZipFile(filename, mode='r', compression=cls.COMPRESSION_TYPE) as sfd:
with sfd.open(cls.metadata_filename) as f:
metadata = cls.read_metadata(f)
return metadata
def load_from_file(self, filename: str) -> None:
"""Reads a Scrutiny Frimware Description file (.sfd) which is just a .zip containing bunch of json files """
with zipfile.ZipFile(filename, mode='r', compression=self.COMPRESSION_TYPE) as sfd:
with sfd.open(self.firmwareid_filename) as f:
self.firmwareid = self.read_firmware_id(f) # This is not a Json file. Content is raw.
with sfd.open(self.metadata_filename, 'r') as f:
self.metadata = self.read_metadata(f) # This is a json file
with sfd.open(self.varmap_filename, 'r') as f:
self.varmap = VarMap(f.read()) # Json file
self.aliases = {}
if self.alias_file in sfd.namelist():
with sfd.open(self.alias_file, 'r') as f:
self.append_aliases(self.read_aliases(f, self.varmap))
@classmethod
def read_firmware_id(cls, f: IO[bytes]) -> bytes:
return bytes.fromhex(f.read().decode('ascii'))
@classmethod
def read_metadata(cls, f: IO[bytes]) -> SFDMetadata:
FIELDS_TYPE:TypeAlias = List[Tuple[str, Type[Any]]]
metadata_dict = cast(MetadataTypedDict, json.loads(f.read().decode('utf8')))
if not isinstance(metadata_dict, dict):
return {}
def remove_bad_fields(obj:Any, fields:FIELDS_TYPE) -> None:
obj2 = cast(Dict[str, Any], obj)
for field in fields:
if field[0] in obj2 and not isinstance(obj2[field[0]], field[1]):
del obj2[field[0]]
fields1:FIELDS_TYPE = [
('project_name', str),
('author', str),
('version', str),
('generation_info', dict)
]
remove_bad_fields(metadata_dict, fields1)
if 'generation_info' in metadata_dict:
fields2:FIELDS_TYPE = [
('python_version', str),
('scrutiny_version', str),
('system_type', str),
('time', int)
]
remove_bad_fields(metadata_dict['generation_info'], fields2)
generation_timestamp = None
generation_info = metadata_dict.get('generation_info', {})
if generation_info is None:
generation_info = cast(GenerationInfoTypedDict, {})
generation_timestamp = generation_info.get('time', None)
return SFDMetadata(
author=metadata_dict.get('author', None),
project_name=metadata_dict.get('project_name', None),
version=metadata_dict.get('version', None),
generation_info=SFDGenerationInfo(
python_version=generation_info.get('python_version', None),
scrutiny_version=generation_info.get('scrutiny_version', None),
system_type=generation_info.get('system_type', None),
timestamp=None if generation_timestamp is None else datetime.fromtimestamp(generation_timestamp),
)
)
@classmethod
def read_aliases(cls, f: IO[bytes], varmap: VarMap) -> Dict[str, Alias]:
aliases_raw: Dict[str, Any] = json.loads(f.read().decode('utf8'))
aliases: Dict[str, Alias] = {}
for k in aliases_raw:
alias = Alias.from_dict(k, aliases_raw[k])
try:
alias.set_target_type(cls.get_alias_target_type(alias, varmap))
except Exception as e:
cls.logger.error("Cannot read alias. %s" % str(e))
aliases[k] = alias
return aliases
@classmethod
def get_alias_target_type(cls, alias: Alias, varmap: VarMap) -> WatchableType:
""" Finds the referred entry and gives this datatype. Alias do not have a datatype by themselves """
if varmap.has_var(alias.get_target()):
return WatchableType.Variable
elif Datastore.is_rpv_path(alias.get_target()):
return WatchableType.RuntimePublishedValue
else:
raise Exception('Alias %s is referencing %s which is not a valid Variable or Runtime Published Value' %
(alias.get_fullpath(), alias.get_target()))
@classmethod
def read_varmap_from_filesystem(cls, path: str) -> VarMap:
if os.path.isfile(path):
fullpath = path
elif os.path.isdir(path):
fullpath = os.path.join(path, cls.varmap_filename)
else:
raise Exception('Cannot find varmap file at %s' % path)
return VarMap(fullpath)
def append_aliases(self, aliases: Dict[str, Alias]) -> None:
"""Add some aliases to the actual SFD"""
for unique_path in aliases:
if unique_path not in self.aliases:
self.aliases[unique_path] = aliases[unique_path]
else:
logging.warning('Duplicate alias %s. Dropping' % unique_path)
def write(self, filename: str) -> None:
"""SFD file format is just a .zip with a bunch of JSON (and a firmwareid file)"""
with zipfile.ZipFile(filename, mode='w', compression=self.COMPRESSION_TYPE) as outzip:
outzip.writestr(self.firmwareid_filename, self.firmwareid.hex())
outzip.writestr(self.metadata_filename, json.dumps(self.metadata.to_dict(), indent=4))
outzip.writestr(self.varmap_filename, self.varmap.get_json())
outzip.writestr(self.alias_file, self.serialize_aliases(list(self.aliases.values())))
@classmethod
def serialize_aliases(cls, aliases: Union[Dict[str, Alias], List[Alias]]) -> bytes:
"""
Takes bunch of alias and return a JSON containing a dict structure like this
[alias1.fullpath] => alias1, [alias2.fullpath] => alias2
"""
if isinstance(aliases, list):
zipped = zip(
[alias.get_fullpath() for alias in aliases],
[alias.to_dict() for alias in aliases]
)
elif isinstance(aliases, dict):
zipped = zip(
[aliases[k].get_fullpath() for k in aliases],
[aliases[k].to_dict() for k in aliases]
)
else:
ValueError('Require a list or a dict of aliases')
return json.dumps(dict(zipped), indent=4).encode('utf8')
def get_firmware_id(self) -> bytes:
return self.firmwareid
def get_firmware_id_ascii(self) -> str:
return self.firmwareid.hex().lower()
def get_endianness(self) -> Endianness:
return self.varmap.get_endianness()
def validate(self) -> None:
if not hasattr(self, 'metadata') or not hasattr(self, 'varmap') or not hasattr(self, 'firmwareid'):
raise Exception('Firmware Description not loaded correctly')
self.validate_metadata()
self.validate_firmware_id()
self.varmap.validate()
def validate_firmware_id(self) -> None:
"""Expects a Firmware ID to have the same length as the default placeholder"""
if len(self.firmwareid) != self.firmware_id_length():
raise Exception('Firmware ID seems to be the wrong length. Found %d bytes, expected %d bytes' %
(len(self.firmwareid), len(firmware_id.PLACEHOLDER)))
def validate_metadata(self) -> None:
if self.metadata.project_name is None:
logging.warning('No valid project name defined in %s' % self.metadata_filename)
if self.metadata.version is None:
logging.warning('No valid version defined in %s' % self.metadata_filename)
if self.metadata.author is None:
logging.warning('No valid author defined in %s' % self.metadata_filename)
def get_vars_for_datastore(self) -> Generator[Tuple[str, Variable], None, None]:
"""Returns all variables in this SFD with a Generator to avoid consuming memory."""
for fullname, vardef in self.varmap.iterate_vars():
yield (fullname, vardef)
def get_aliases_for_datastore(self, entry_type: Optional[WatchableType] = None) -> Generator[Tuple[str, Alias], None, None]:
"""Returns all alias in this SFD with a Generator to avoid consuming memory."""
for k in self.aliases:
if entry_type is None or self.aliases[k].get_target_type() == entry_type:
yield (self.aliases[k].get_fullpath(), self.aliases[k])
def get_aliases(self) -> Dict[str, Alias]:
return self.aliases
def get_metadata(self) -> SFDMetadata:
return self.metadata
@classmethod
def firmware_id_length(cls) -> int:
return len(firmware_id.PLACEHOLDER)