strings_analyzer.py

ofrak.core.strings_analyzer

StringsAnalyzer (Analyzer)

analyze(self, resource, config=None) async

Analyze a resource for to extract specific ResourceAttributes.

Users should not call this method directly; rather, they should run Resource.run or Resource.analyze.

Parameters:

Name	Type	Description	Default
resource	Resource	The resource that is being analyzed	required
config	Optional[ofrak.core.strings_analyzer.StringsAnalyzerConfig]	Optional config for analyzing. If an implementation provides a default, this default will always be used when config would otherwise be None. Note that a copy of the default config will be passed, so the default config values cannot be modified persistently by a component run.	None

Returns:

Type	Description
StringsAttributes	The analysis results

Source code in ofrak/core/strings_analyzer.py

async def analyze(
    self, resource: Resource, config: Optional[StringsAnalyzerConfig] = None
) -> StringsAttributes:
    if config is None:
        config = StringsAnalyzerConfig()

    strings = dict()
    with tempfile.NamedTemporaryFile() as temp_file:
        temp_file.write(await resource.get_data())
        temp_file.flush()

        proc = await asyncio.subprocess.create_subprocess_exec(
            "strings",
            "-t",
            "d",
            f"-{config.min_length}",
            temp_file.name,
            stdout=asyncio.subprocess.PIPE,
        )

        line = await proc.stdout.readline()  # type: ignore
        while line:
            line = line.decode("ascii").strip()
            try:
                offset, string = line.split(" ", maxsplit=1)
            except ValueError as e:
                # String consisted entirely of whitespace
                line = await proc.stdout.readline()  # type: ignore
                continue
            strings[int(offset)] = string
            line = await proc.stdout.readline()  # type: ignore
        await proc.wait()

    return StringsAttributes(strings)

StringsAnalyzerConfig (ComponentConfig) dataclass

StringsAnalyzerConfig(min_length: int = 8)

StringsAttributes (ResourceAttributes) dataclass

StringsAttributes(strings: Dict[int, str])

_StringsToolDependency (ComponentExternalTool) private

__init__(self) special

Initialize self. See help(type(self)) for accurate signature.

Source code in ofrak/core/strings_analyzer.py

def __init__(self):
    super().__init__(
        "strings",
        "https://linux.die.net/man/1/strings",
        "--help",
        apt_package="binutils",
        brew_package="binutils",
    )

is_tool_installed(self) async

Check if a tool is installed by running it with the install_check_arg. This method runs <tool> <install_check_arg>.

Returns:

Type	Description
bool	True if the tool command returned zero, False if tool could not be found or returned non-zero exit code.

Source code in ofrak/core/strings_analyzer.py

async def is_tool_installed(self) -> bool:
    try:
        cmd = [
            self.tool,
            self.install_check_arg,
        ]
        proc = await asyncio.create_subprocess_exec(
            *cmd,
            stdout=asyncio.subprocess.DEVNULL,
            stderr=asyncio.subprocess.DEVNULL,
        )

        # ignore returncode because "strings --help" on Mac has returncode 1
        await proc.wait()
    except FileNotFoundError:
        return False

    return True