J. S. Jimmy Li

13 papers Misc 3Journal 2Unranked 8
YearRankTypeTitle / Venue / Authors
2015 conf
VISAPP (1)
Damian Tohl, J. S. Jimmy Li, C. Michael Bull
2013 Misc conf
IVCNZ
Sharmil Randhawa, J. S. Jimmy Li
2011 Misc conf
DICTA
Sharmil Randhawa, J. S. Jimmy Li
2010 Misc conf
DICTA
J. S. Jimmy Li, Sharmil Randhawa
2009 J jnl
IEEE Trans. Image Process.
J. S. Jimmy Li, Sharmil Randhawa
2007 conf
ICASSP (1)
J. S. Jimmy Li, Sharmil Randhawa
2006 conf
VISAPP (1)
J. S. Jimmy Li, Sharmil Randhawa
2005 conf
ICIAR
J. S. Jimmy Li, Sharmil Randhawa
2005 conf
ISSPA
J. S. Jimmy Li, Sharmil Randhawa
2004 conf
ACSC
J. S. Jimmy Li, Sharmil Randhawa
1999 conf
ISSPA
J. S. Jimmy Li, Michael D. E. Turley
1995 J jnl
IEEE Trans. Image Process.
J. S. Jimmy Li, Anand Ramsingh
1994 conf
ICASSP (5)
J. S. Jimmy Li, Anand Ramsingh
redb/extractors/apk_extractors/apk_features.py
← Index redb/extractors/apk_extractors/apk_features.py python
import inspect
import zipfile
from datetime import datetime, timezone
from typing import Any

from redb.extractors.enum import Tag
from redb.extractors.apk_extractor import APKExtractor
from redb.models.dataclasses import APKFeatures


class APKFeaturesExtractor(APKExtractor):

    def __init__(
        self, filepath, log, exporters=None, index_prefix=None,
        known_benign=False, known_malicious=False,
        apk=None,
    ):
        super().__init__(
            filepath, log, exporters, index_prefix,
            known_benign, known_malicious, apk,
        )
        self.apk_features = None
        self.log.debug(inspect.currentframe().f_code.co_name)

    def tag(self):
        return Tag.APK_FEATURES.value

    def _extract_zip_timestamps(self):
        """Extract earliest and latest content modification from ZIP entries."""
        earliest = None
        latest = None
        try:
            zf = self._get_zip_file()
            if zf:
                with zf:
                    for info in zf.infolist():
                        try:
                            dt = datetime(*info.date_time)
                            if earliest is None or dt < earliest:
                                earliest = dt
                            if latest is None or dt > latest:
                                latest = dt
                        except (ValueError, TypeError):
                            continue
        except Exception as e:
            self.log.warning(f"Error extracting ZIP timestamps: {e}")
        return (
            earliest.isoformat() if earliest else None,
            latest.isoformat() if latest else None,
        )

    def _extract_supported_abis(self):
        """Determine supported ABIs from lib/ directory."""
        abis = set()
        for f in self._list_files():
            if f.startswith("lib/") and f.endswith(".so"):
                parts = f.split("/")
                if len(parts) >= 3:
                    abis.add(parts[1])
        return sorted(abis)

    def _count_dex_files(self):
        """Count DEX files and compute total size."""
        dex_count = 0
        total_size = 0
        try:
            zf = self._get_zip_file()
            if zf:
                with zf:
                    for info in zf.infolist():
                        if info.filename.endswith(".dex"):
                            dex_count += 1
                            total_size += info.file_size
        except Exception as e:
            self.log.warning(f"Error counting DEX files: {e}")
        return dex_count, total_size

    def _check_embedded_apk(self):
        """Check if the archive contains nested APK files."""
        for f in self._list_files():
            if f.lower().endswith(".apk"):
                return True
        return False

    def _safe_extract(self, field_name, func, default=None):
        """Extract a single field, logging and returning default on failure."""
        try:
            return func()
        except Exception as e:
            self.log.warning(
                f"Error extracting APK field '{field_name}' for "
                f"{self.hash.sha256}: {e}"
            )
            return default

    def extract(self):
        if not self._is_valid_apk():
            self.log.error(f"Invalid APK for {self.hash.sha256}")
            return None

        package_name = self._safe_extract(
            "package_name", lambda: self.apk.get_package()
        )
        app_name = self._safe_extract(
            "app_name", lambda: self.apk.get_app_name()
        )

        def _get_version_code():
            try:
                return int(self.apk.get_androidversion_code() or 0)
            except (ValueError, TypeError):
                return 0

        version_code = self._safe_extract("version_code", _get_version_code)
        version_name = self._safe_extract(
            "version_name", lambda: self.apk.get_androidversion_name()
        )

        def _get_sdk(getter):
            val = getter()
            return int(val) if val else None

        min_sdk = self._safe_extract(
            "min_sdk_version", lambda: _get_sdk(self.apk.get_min_sdk_version)
        )
        target_sdk = self._safe_extract(
            "target_sdk_version", lambda: _get_sdk(self.apk.get_target_sdk_version)
        )
        compile_sdk = self._safe_extract(
            "compile_sdk_version",
            lambda: _get_sdk(self.apk.get_effective_target_sdk_version),
        )

        main_activity = self._safe_extract(
            "main_activity", lambda: self.apk.get_main_activity()
        )

        is_debuggable = self._safe_extract(
            "is_debuggable",
            lambda: self.apk.get_attribute_value(
                "application", "debuggable"
            ) == "true",
            False,
        )
        allow_backup = self._safe_extract(
            "allow_backup",
            lambda: self.apk.get_attribute_value(
                "application", "allowBackup"
            ) != "false",
            True,
        )
        uses_cleartext = self._safe_extract(
            "uses_cleartext_traffic",
            lambda: self.apk.get_attribute_value(
                "application", "usesCleartextTraffic"
            ) == "true",
            False,
        )

        supported_abis = self._safe_extract(
            "supported_abis", self._extract_supported_abis, []
        )
        dex_count, total_dex_size = self._safe_extract(
            "dex_files", self._count_dex_files, (0, 0)
        )
        all_files = self._safe_extract("file_list", self._list_files, [])
        total_file_count = len(all_files)
        has_native_code = any(
            f.startswith("lib/") and f.endswith(".so") for f in all_files
        )
        has_assets = any(f.startswith("assets/") for f in all_files)
        contains_embedded_apk = self._safe_extract(
            "contains_embedded_apk", self._check_embedded_apk, False
        )

        uses_libraries = self._safe_extract(
            "uses_libraries",
            lambda: list(self.apk.get_libraries() or []),
            [],
        )

        earliest_mod, latest_mod = self._safe_extract(
            "zip_timestamps", self._extract_zip_timestamps, (None, None)
        )

        self.apk_features = APKFeatures(
            package_name=package_name,
            app_name=app_name,
            version_code=version_code,
            version_name=version_name,
            min_sdk_version=min_sdk,
            target_sdk_version=target_sdk,
            compile_sdk_version=compile_sdk,
            main_activity=main_activity,
            is_debuggable=is_debuggable,
            allow_backup=allow_backup,
            uses_cleartext_traffic=uses_cleartext,
            supported_abis=supported_abis,
            dex_count=dex_count,
            total_dex_size=total_dex_size,
            total_file_count=total_file_count,
            has_native_code=has_native_code,
            has_assets=has_assets,
            uses_libraries=uses_libraries,
            earliest_content_modification=earliest_mod,
            latest_content_modification=latest_mod,
            contains_embedded_apk=contains_embedded_apk,
        )
        return self.apk_features

    def prepare_export_data(self, exporter_type: str) -> Any:
        if exporter_type == "ClickHouseExporter":
            if not self.apk_features:
                return None

            f = self.apk_features
            current_time = datetime.now(timezone.utc)
            data = [[
                self.sha256,
                f.package_name,
                f.app_name,
                f.version_code,
                f.version_name,
                f.min_sdk_version,
                f.target_sdk_version,
                f.compile_sdk_version,
                f.main_activity,
                int(f.is_debuggable),
                int(f.allow_backup),
                int(f.uses_cleartext_traffic),
                f.supported_abis,
                f.dex_count,
                f.total_dex_size,
                f.total_file_count,
                int(f.has_native_code),
                int(f.has_assets),
                f.uses_libraries,
                f.earliest_content_modification,
                f.latest_content_modification,
                int(f.contains_embedded_apk),
                current_time,
            ]]

            column_names = [
                "sha256",
                "package_name", "app_name", "version_code", "version_name",
                "min_sdk_version", "target_sdk_version", "compile_sdk_version",
                "main_activity",
                "is_debuggable", "allow_backup", "uses_cleartext_traffic",
                "supported_abis",
                "dex_count", "total_dex_size", "total_file_count",
                "has_native_code", "has_assets",
                "uses_libraries",
                "earliest_content_modification", "latest_content_modification",
                "contains_embedded_apk",
                "analysis_date",
            ]

            column_type_names = [
                "FixedString(64)",
                "Nullable(String)", "Nullable(String)", "Nullable(UInt32)", "Nullable(String)",
                "Nullable(UInt16)", "Nullable(UInt16)", "Nullable(UInt16)",
                "Nullable(String)",
                "UInt8", "UInt8", "UInt8",
                "Array(String)",
                "UInt16", "UInt64", "UInt32",
                "UInt8", "UInt8",
                "Array(String)",
                "Nullable(String)", "Nullable(String)",
                "UInt8",
                "DateTime64(3, 'UTC')",
            ]

            return (data, column_names, column_type_names)

    def get_clickhouse_table(self) -> str:
        return "redb_apk_features"