Vicky Chan

16 papers Journal 5Unranked 11
YearRankTypeTitle / Venue / Authors
2025 conf
ICORR
Luis Garcia-Fernandez, Andria J. Farrens, Raymond Rojas, Vicky Chan, Eric T. Wolbrecht, Joel C. Perry, David J. Reinkensmeyer
2025 conf
ICORR
Andria J. Farrens, Vicky Chan, Luis Garcia-Fernandez, Ziqiang "Joe" Zhu, Jun Min Kim, Matthew Karl Farrens, Samuel T. King
2025 J jnl
CoRR
Andria J. Farrens, Luis Garcia-Fernandez, Raymond Rojas, Jillian Obeso Estrada, Dylan S. Reinsdorf, Vicky Chan, Disha Gupta, Joel C. Perry, Eric T. Wolbrecht, An Do, Steven C. Cramer, David J. Reinkensmeyer
2025 conf
ICORR
Caitlin M. Callaghan, Christopher A. Johnson, Piyashi Biswas, Jill See, Lucy Dodakian, Vicky Chan, Po T. Wang, Steven C. Cramer, Zoran Nenadic, An H. Do, David J. Reinkensmeyer
2025 conf
ICORR
Christopher A. Johnson, Piyashi Biswas, Jill See, Olivia Briendel, Vicky Chan, Lucy Dodakian, Po T. Wang, Zoran Nenadic, Steven C. Cramer, An Do, David J. Reinkensmeyer
2024 J jnl
CoRR
Christopher A. Johnson, Piyashi Biswas, Rubi Tapia, Jill See, Lucy Dodakian, Vicky Chan, Po T. Wang, Zoran Nenadic, An H. Do, David J. Reinkensmeyer
2023 J jnl
Sensors
Shusuke Okita, Roman Yakunin, Jathin Korrapati, Mina Ibrahim, Diogo Schwerz de Lucena, Vicky Chan, David J. Reinkensmeyer
2022 J jnl
Sensors
Diogo Schwerz de Lucena, Justin B. Rowe, Shusuke Okita, Vicky Chan, Steven C. Cramer, David J. Reinkensmeyer
2021 J jnl
Sensors
Diogo Schwerz de Lucena, Justin B. Rowe, Vicky Chan, David J. Reinkensmeyer
2021 conf
EMBC
Shusuke Okita, Diogo Schwerz de Lucena, Vicky Chan, David J. Reinkensmeyer
2017 conf
ICORR
Yasemin Sarigul-Klijn, Joan Lobo-Prat, Brendan W. Smith, Sage Thayer, Daniel Zondervan, Vicky Chan, Oliver Stoller, David J. Reinkensmeyer
2017 conf
ICORR
Diogo S. de Lucena, Oliver Stoller, Justin B. Rowe, Vicky Chan, David J. Reinkensmeyer
2014 conf
EMBC
Brendan W. Smith, Daniel K. Zondervan, Thomas J. Lord, Vicky Chan, David J. Reinkensmeyer
2014 conf
EMBC
Justin B. Rowe, Nizan Friedman, Vicky Chan, Steven C. Cramer, Mark Bachman, David J. Reinkensmeyer
2012 conf
EMBC
Hossein Taheri, Justin B. Rowe, David Gardner, Vicky Chan, David J. Reinkensmeyer, Eric T. Wolbrecht
2011 conf
EMBC
Nizan Friedman, Vicky Chan, Danny Zondervan, Mark Bachman, David J. Reinkensmeyer
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"