Xi Lu

20 papers A* 8A 1Journal 8Unranked 3
YearRankTypeTitle / Venue / Authors
2026 J jnl
CoRR
Xi Lu, Di Hu, An T. Nguyen, Brad Morse, Lisa M. Schilling, Kai Zheng, Michelle S. Keller, Lucila Ohno-Machado, Yunan Chen
2025 A* conf
CHI
Lucas M. Silva, Xi Lu, Emily X. Liang, Daniel A. Epstein
2025 A* conf
CHI
Lika Haizhou Liu, Xi Lu, Pei-Chun Chiang, Daniel A. Epstein, Kurt Squire
2025 A* conf
CHI
Kwangyoung Lee, Yeohyun Jung, Gyuwon Jung, Xi Lu, Hwajung Hong
2025 J jnl
CoRR
Di Hu, Xi Lu, Yunan Chen, Michelle Keller, An T. Nguyen, Vu Le, Tsung-Ting Kuo, Lucila Ohno-Machado, Kai Zheng
2025 A* conf
CHI
Daye Kang, Jingjin Li, Gilly Leshed, Jeffrey M. Rzeszotarski, Xi Lu
2024 J jnl
Proc. ACM Hum. Comput. Interact.
Xi Lu, Jacquelyn E. Powell, Elena Agapie, Yunan Chen, Daniel A. Epstein
2024 A* conf
CHI
John Chen, Xi Lu, Yuzhou Du, Michael Rejtig, Ruth Bagley, Mike S. Horn, Uri Wilensky
2024 J jnl
CoRR
John Chen, Xi Lu, Michael Rejtig, David Du, Ruth Bagley, Michael S. Horn, Uri J. Wilensky
2024 conf
CSCW Companion
Qingxiao Zheng, Xi Lu, Qiao Jin, Jitesh Jain, Hedda Meadan-Kaplansky, Humphrey Shi, Jinjun Xiong, Yun Huang
2024 A* conf
CHI
Xi Lu, Jacquelyn E. Powell, Elena Agapie, Yunan Chen, Daniel A. Epstein
2022 conf
CSCW Companion
Lika Haizhou Liu, Xi Lu, Richard Martinez, Dennis Wang, Fannie Liu, Andrés Monroy-Hernández, Daniel A. Epstein
2022 J jnl
Proc. ACM Hum. Comput. Interact.
Xi Lu, Eunkyung Jo, Seora Park, Hwajung Hong, Yunan Chen, Daniel A. Epstein
2022 J jnl
Proc. ACM Interact. Mob. Wearable Ubiquitous Technol.
Xi Lu, Edison Thomaz, Daniel A. Epstein
2021 J jnl
Proc. ACM Hum. Comput. Interact.
Xi Lu, Yunan Chen, Daniel A. Epstein
2021 A* conf
CHI
Xi Lu, Tera L. Reynolds, Eunkyung Jo, Hwajung Hong, Xinru Page, Yunan Chen, Daniel A. Epstein
2021 A conf
Conference on Designing Interactive Systems
Xi Lu, Yunan Chen, Daniel A. Epstein
2020 J jnl
Proc. ACM Interact. Mob. Wearable Ubiquitous Technol.
Daniel A. Epstein, Clara Marques Caldeira, Mayara Costa Figueiredo, Xi Lu, Lucas M. Silva, Lucretia Williams, Jong Ho Lee, Qingyang Li, Simran Ahuja, Qiuer Chen, Payam Dowlatyari, Craig Hilby, Sazeda Sultana, Elizabeth V. Eikey, Yunan Chen
2019 conf
CHI Extended Abstracts
Xi Lu, Xiaohang Liu, Erik Stolterman Bergqvist
2019 A* conf
CHI
Guo Freeman, Jeffrey Bardzell, Shaowen Bardzell, Szu-Yu (Cyn) Liu, Xi Lu, Diandian Cao
redb/extractors/macho_extractors/macho_universal.py
← Index redb/extractors/macho_extractors/macho_universal.py python
import hashlib
import inspect
import json
from datetime import datetime, timezone
from typing import Any, List

from redb.extractors.enum import Tag
from redb.extractors.macho_extractor import MachOExtractor
from redb.models.dataclasses import MachOUniversal


class MachOUniversalExtractor(MachOExtractor):

    def __init__(
        self,
        filepath,
        log,
        exporters=None,
        index_prefix=None,
        elastic_index=None,
        known_benign=False,
        known_malicious=False,
        macho=None,
    ):
        super().__init__(
            filepath,
            log,
            exporters,
            index_prefix,
            elastic_index,
            known_benign,
            known_malicious,
            macho,
        )
        self.elastic_index = self.index_prefix + "-macho_universal"
        self.log.debug(inspect.currentframe().f_code.co_name)

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

    def _extract_universal_info(self):
        """Extract Universal/FAT binary architecture information using new API."""
        self.log.debug(inspect.currentframe().f_code.co_name)

        if not self.macho:
            return None

        try:
            # Parse at Universal level first (new API requirement)
            self.macho.parse()

            # Get architectures using new API
            architectures = self.macho.get_architectures()
            if not architectures:
                return None

            # Check if this is a FAT binary
            is_fat = len(architectures) > 1

            architecture_info = []

            # Extract info for each architecture
            for arch_name in architectures:
                try:
                    # Get general info for this architecture
                    general_info = self.macho.get_general_info(arch=arch_name)

                    # Get header info for this architecture
                    header_info = self.macho.get_macho_header(arch=arch_name)

                    # Get architecture-specific MachO instance for detailed analysis
                    arch_macho = self.macho.get_macho_for_arch(arch_name)

                    # Calculate architecture slice hash (if we can access the raw data)
                    arch_sha256 = None
                    arch_md5 = None
                    arch_sha1 = None

                    # For FAT binaries, try to get slice-specific info
                    if is_fat and arch_macho:
                        try:
                            # This would require access to the slice data
                            # For now, we'll use the general file info
                            arch_sha256 = general_info.get('SHA256', '') if general_info else ''
                            arch_md5 = general_info.get('MD5', '') if general_info else ''
                            arch_sha1 = general_info.get('SHA1', '') if general_info else ''
                        except Exception as e:
                            self.log.debug(f"Could not extract slice hash for {arch_name}: {e}")

                    architecture_info.append({
                        'architecture': arch_name,
                        'arch_sha256': arch_sha256,
                        'arch_md5': arch_md5,
                        'arch_sha1': arch_sha1,
                        'cputype': header_info.get('cputype') if header_info else None,
                        'cpusubtype': header_info.get('cpusubtype') if header_info else None,
                        'filetype': header_info.get('filetype') if header_info else None
                    })

                except Exception as e:
                    self.log.warning(f"Error extracting info for architecture {arch_name}: {e}")
                    continue

            # Create Universal dataclass
            macho_universal = MachOUniversal(
                is_fat=is_fat,
                architecture_count=len(architectures),
                architectures=architectures,
                architecture_info=architecture_info,
                fat_hash=self.sha256,
                fat_md5=self.md5,
                fat_sha1=self.sha1
            )

            return macho_universal

        except Exception as e:
            self.log.error(f"Error extracting MachO Universal info: {e}")
            return None

    def _extract_fat_architecture_mappings(self):
        """Extract detailed FAT binary architecture mappings for database relationships."""
        self.log.debug(inspect.currentframe().f_code.co_name)

        if not self.macho:
            return []

        try:
            # Parse at Universal level first
            self.macho.parse()

            # Get architectures using new API
            architectures = self.macho.get_architectures()
            if not architectures or len(architectures) <= 1:
                return []  # Not a FAT binary

            mappings = []
            current_time = datetime.now(timezone.utc)

            # For each architecture, create a mapping record
            for arch_name in architectures:
                try:
                    # Get general info
                    general_info = self.macho.get_general_info()

                    # Create mapping record for FAT binary architecture table
                    mapping = {
                        'fat_hash': self.sha256,  # SHA256 of the FAT binary
                        'architecture': arch_name,
                        'arch_sha256': general_info.get('SHA256', '') if general_info else '',  # Will need proper slice extraction
                        'arch_md5': general_info.get('MD5', '') if general_info else '',
                        'arch_sha1': general_info.get('SHA1', '') if general_info else '',
                        'arch_filename': f"{general_info.get('Filename', '')}.{arch_name}" if general_info else '',
                        'analysis_date': current_time
                    }
                    mappings.append(mapping)

                except Exception as e:
                    self.log.warning(f"Error creating mapping for architecture {arch_name}: {e}")
                    continue

            return mappings

        except Exception as e:
            self.log.error(f"Error extracting FAT architecture mappings: {e}")
            return []

    def extract(self):
        self.log.debug(inspect.currentframe().f_code.co_name)
        try:
            universal_info = self._extract_universal_info()
            return universal_info
        except Exception as e:
            self.log.error(f"Error extracting MachO Universal info: {e}")
            return None

    def extract_fat_binary_basic_properties_data(self):
        """Extract data needed for creating multiple BasicProperties records for FAT binaries.

        Returns:
            Tuple: (is_fat, fat_sha256, architectures_info) where:
                - is_fat: bool indicating if this is a FAT binary
                - fat_sha256: SHA256 of the FAT wrapper
                - architectures_info: dict with arch names and their hashes
        """
        self.log.debug(inspect.currentframe().f_code.co_name)

        if not self.macho:
            return False, None, {}

        try:
            # Parse at Universal level first
            self.macho.parse()

            # Get architectures using new API
            architectures = self.macho.get_architectures()
            if not architectures or len(architectures) <= 1:
                return False, None, {}  # Not a FAT binary

            # This is a FAT binary
            architectures_info = {}

            for arch_name in architectures:
                try:
                    # Get general info for this architecture
                    general_info = self.macho.get_general_info(arch=arch_name)

                    if general_info:
                        architectures_info[arch_name] = {
                            'sha256': general_info.get('SHA256', ''),
                            'md5': general_info.get('MD5', ''),
                            'sha1': general_info.get('SHA1', ''),
                            'filename': general_info.get('Filename', ''),
                            'filesize': general_info.get('Filesize', 0)
                        }
                except Exception as e:
                    self.log.warning(f"Error extracting info for architecture {arch_name}: {e}")
                    continue

            return True, self.sha256, architectures_info

        except Exception as e:
            self.log.error(f"Error extracting FAT binary data: {e}")
            return False, None, {}

    def prepare_export_data(self, exporter_type: str) -> Any:
        if exporter_type == "ElasticsearchExporter":
            return self.extract()
        elif exporter_type == "ClickHouseExporter":
            universal_info = self.extract()
            if universal_info is None:
                return None

            data = []
            current_time = datetime.now(timezone.utc)

            # Get architecture info for the binary
            try:
                if universal_info.is_fat:
                    # For FAT binaries, architecture fields should be NULL since it contains multiple
                    architecture_raw = None
                    architecture_str = None
                else:
                    # For single-arch binaries, get the actual architecture info
                    header_info = self.macho.get_macho_header()
                    architecture_raw = header_info.get('cputype', 0) if header_info else 0
                    architecture_str = universal_info.architectures[0] if universal_info.architectures else None
            except Exception as e:
                self.log.warning(f"Could not get architecture info for binary: {e}")
                architecture_raw = None
                architecture_str = None

            # Main Universal binary record
            data.append([
                self.sha256,                              # sha256
                self.md5,                                 # md5
                self.sha1,                                # sha1
                None,                                     # parent_sha256 (always None for main FAT binary)
                architecture_raw,                         # architecture (raw CPU type)
                architecture_str,                         # architecture_str (human-readable)
                universal_info.is_fat,                    # is_fat
                universal_info.architecture_count,       # architecture_count
                universal_info.architectures,            # architectures (array)
                json.dumps(universal_info.architecture_info[0] if len(universal_info.architecture_info) == 1 else {"architectures": universal_info.architecture_info}) if universal_info.architecture_info else None,  # architecture_info (JSON)
                current_time,                             # analysis_date
            ])

            column_names = [
                'sha256', 'md5', 'sha1', 'parent_sha256', 'architecture', 'architecture_str',
                'is_fat', 'architecture_count', 'architectures', 'architecture_info',
                'analysis_date'
            ]

            column_type_names = [
                'FixedString(64)', 'FixedString(32)', 'FixedString(40)',
                'Nullable(FixedString(64))', 'Nullable(UInt32)', 'LowCardinality(Nullable(String))',
                'UInt8', 'UInt32', 'Array(LowCardinality(String))', 'JSON',
                'DateTime64(3, \'UTC\')'
            ]

            return (data, column_names, column_type_names)

        return None

    def prepare_fat_architecture_export_data(self) -> Any:
        """Prepare export data for the FAT binary architecture mapping table."""
        mappings = self._extract_fat_architecture_mappings()
        if not mappings:
            return None

        data = []
        for mapping in mappings:
            data.append([
                mapping['fat_hash'],
                mapping['architecture'],
                mapping['arch_sha256'],
                mapping['arch_md5'],
                mapping['arch_sha1'],
                mapping['arch_filename'],
                mapping['analysis_date'],
            ])

        column_names = [
            'fat_hash', 'architecture', 'arch_sha256', 'arch_md5', 'arch_sha1',
            'arch_filename', 'analysis_date'
        ]

        column_type_names = [
            'FixedString(64)', 'LowCardinality(String)', 'FixedString(64)',
            'FixedString(32)', 'FixedString(40)', 'String',
            'DateTime64(3, \'UTC\')'
        ]

        return (data, column_names, column_type_names)

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

    # def get_fat_architecture_table(self) -> str:
    #     """Return table name for FAT binary architecture mappings."""
    #     return "redb_fat_binary_architectures"