Repository: mandiant/capa
File: capa/ghidra/capa_explorer.py (Python)

Code before:

def main():
    logging.basicConfig(level=logging.INFO)
    logging.getLogger().setLevel(logging.INFO)

    if isRunningHeadless():  # type: ignore [name-defined] # noqa: F821
        logger.error("unsupported ghidra execution mode")
        return capa.main.E_UNSUPPORTED_GHIDRA_EXECUTION_MODE

    if not capa.ghidra.helpers.is_supported_ghidra_version():
        logger.error("unsupported ghidra version")
        return capa.main.E_UNSUPPORTED_GHIDRA_VERSION

    if not capa.ghidra.helpers.is_supported_file_type():
        logger.error("unsupported file type")
        return capa.main.E_INVALID_FILE_TYPE

    if not capa.ghidra.helpers.is_supported_arch_type():
        logger.error("unsupported file architecture")
        return capa.main.E_INVALID_FILE_ARCH

    # capa_data will always contain {'meta':..., 'rules':...}
    # if the 'rules' key contains no values, then there were no matches
    # found
    capa_data = json.loads(get_capabilities())
    if not capa_data.get("rules"):
        logger.info("capa explorer found no matches")
        popup("capa explorer found no matches.")  # type: ignore [name-defined] # noqa: F821
        return capa.main.E_EMPTY_REPORT

    for item in parse_json(capa_data):
        item.tag_functions()
        item.bookmark_locations()
    logger.info("capa explorer analysis complete")
    popup("""capa explorer analysis complete.\nPlease see results in the Bookmarks and Namespaces section of the Symbol Tree Window.""")  # type: ignore [name-defined] # noqa: F821
    return 0


if __name__ == "__main__":
    if sys.version_info < (3, 8):
        from capa.exceptions import UnsupportedRuntimeError

        raise UnsupportedRuntimeError("This version of capa can only be used with Python 3.8+")
    exit_code = main()
    if exit_code != 0:
        popup("Capa Explorer encountered errors during analysis. Please check the console output for more information.")  # type: ignore [name-defined] # noqa: F821
    sys.exit(exit_code)


Review comment (suggestion):
```suggestion
    if capa_data.get("rules") is None:
```

Code after:

    capabilities, counts = capa.main.find_capabilities(rules, extractor, True)

    if capa.main.has_file_limitation(rules, capabilities, is_standalone=False):
        popup("capa explorer encountered warnings during analysis. Please check the console output for more information.")  # type: ignore [name-defined] # noqa: F821
        logger.info("capa encountered warnings during analysis")

    return capa.render.json.render(meta, rules, capabilities)


def get_locations(match_dict):
    """recursively collect match addresses and associated nodes"""

    for loc in match_dict.get("locations", {}):
        # either an rva (absolute)
        # or an offset into a file (file)
        if loc.get("type", "") in ("absolute", "file"):
            yield loc.get("value"), match_dict.get("node")

    for child in match_dict.get("children", {}):
        yield from get_locations(child)


def parse_node(node_data):
    """pull match descriptions and sub features by parsing node dicts"""

    node = node_data.get(node_data.get("type"))

    if "description" in node:
        yield "description", node.get("description")

    data = node.get(node.get("type"))
    if isinstance(data, (str, int)):
        feat_type = node.get("type")
        if isinstance(data, int):
            data = hex(data)
        yield feat_type, data


def parse_json(capa_data):
    """Parse json produced by capa"""

    for rule, capability in capa_data.get("rules", {}).items():
        # structure to contain rule match address & supporting feature data
        # {rule match addr:[{feature addr:{node_data}}]}
        rule_matches: Dict[Any, List[Any]] = {}
        for i in range(len(capability.get("matches"))):
            # grab rule match location
            match_loc = capability.get("matches")[i][0].get("value")
            if match_loc is None:
                # Ex. See "Reference Base64 string"