Ozan Sener

58 papers A* 18B 1Misc 1Journal 32Unranked 6
YearRankTypeTitle / Venue / Authors
2026 J jnl
CoRR
Luca Moschella, Laura Manduchi, Ozan Sener
2025 A* conf
ICML
Antoine Wehenkel, Juan L. Gamella, Ozan Sener, Jens Behrmann, Guillermo Sapiro, Jörn-Henrik Jacobsen, Marco Cuturi
2025 A* conf
ICML
Marco Francis Cusumano-Towner, David Hafner, Alexander Hertzberg, Brody Huval, Aleksei Petrenko, Eugene Vinitsky, Erik Wijmans, Taylor W. Killian, Stuart Bowers, Ozan Sener, Philipp Krähenbühl, Vladlen Koltun
2025 J jnl
CoRR
Marco F. Cusumano-Towner, David Hafner, Alexander Hertzberg, Brody Huval, Aleksei Petrenko, Eugene Vinitsky, Erik Wijmans, Taylor W. Killian, Stuart Bowers, Ozan Sener, Philipp Krähenbühl, Vladlen Koltun
2024 J jnl
CoRR
Antoine Wehenkel, Juan L. Gamella, Ozan Sener, Jens Behrmann, Guillermo Sapiro, Marco Cuturi, Jörn-Henrik Jacobsen
2024 J jnl
CoRR
Laura Manduchi, Antoine Wehenkel, Jens Behrmann, Luca Pegolotti, Andy C. Miller, Ozan Sener, Marco Cuturi, Guillermo Sapiro, Jörn-Henrik Jacobsen
2024 J jnl
CoRR
Ameya Prabhu, Shiven Sinha, Ponnurangam Kumaraguru, Philip H. S. Torr, Ozan Sener, Puneet K. Dokania
2024 A* conf
NeurIPS
Ameya Prabhu, Shiven Sinha, Ponnurangam Kumaraguru, Philip Torr, Ozan Sener, Puneet K. Dokania
2023 J jnl
CoRR
Ozan Sener, Vladlen Koltun
2023 J jnl
IEEE Trans. Pattern Anal. Mach. Intell.
Hexiang Hu, Ozan Sener, Fei Sha, Vladlen Koltun
2023 A* conf
ICCV
Yeti Ziya Gürbüz, Ozan Sener, A. Aydin Alatan
2023 J jnl
CoRR
Yeti Ziya Gurbuz, Ozan Sener, A. Aydin Alatan
2023 J jnl
IEEE Trans. Pattern Anal. Mach. Intell.
John Lambert, Zhuang Liu, Ozan Sener, James Hays, Vladlen Koltun
2023 J jnl
CoRR
Ameya Prabhu, Zhipeng Cai, Puneet K. Dokania, Philip H. S. Torr, Vladlen Koltun, Ozan Sener
2023 J jnl
CoRR
Antoine Wehenkel, Jens Behrmann, Andrew C. Miller, Guillermo Sapiro, Ozan Sener, Marco Cuturi, Jörn-Henrik Jacobsen
2022 A* conf
NeurIPS
Ozan Sener, Vladlen Koltun
2022 A* conf
ICML
Katelyn Gao, Ozan Sener
2022 J jnl
CoRR
Katelyn Gao, Ozan Sener
2022 J jnl
CoRR
Zhipeng Cai, Vladlen Koltun, Ozan Sener
2021 J jnl
CoRR
John Lambert, Zhuang Liu, Ozan Sener, James Hays, Vladlen Koltun
2021 A* conf
ICCV
Zhipeng Cai, Ozan Sener, Vladlen Koltun
2021 J jnl
CoRR
Zhipeng Cai, Ozan Sener, Vladlen Koltun
2020 A* conf
ICLR
Eduard Gorbunov, Adel Bibi, Ozan Sener, El Houcine Bergou, Peter Richtárik
2020 A* conf
AAAI
Adel Bibi, El Houcine Bergou, Ozan Sener, Bernard Ghanem, Peter Richtárik
2020 J jnl
CoRR
Hexiang Hu, Ozan Sener, Fei Sha, Vladlen Koltun
2020 A* conf
NeurIPS
Umut Simsekli, Ozan Sener, George Deligiannidis, Murat A. Erdogdu
2020 J jnl
CoRR
Umut Simsekli, Ozan Sener, George Deligiannidis, Murat A. Erdogdu
2020 A* conf
ICLR
Ozan Sener, Vladlen Koltun
2020 J jnl
CoRR
Ozan Sener, Vladlen Koltun
2020 A* conf
CVPR
John Lambert, Zhuang Liu, Ozan Sener, James Hays, Vladlen Koltun
2020 A* conf
NeurIPS
Katelyn Gao, Ozan Sener
2020 J jnl
CoRR
Katelyn Gao, Ozan Sener
2019 J jnl
Comput. Graph. Forum
He Wang, Sören Pirk, Ersin Yumer, Vladimir G. Kim, Ozan Sener, Srinath Sridhar, Leonidas J. Guibas
2018 conf
ICLR (Poster)
Ozan Sener, Silvio Savarese
2018 A* conf
CVPR
John Lambert, Ozan Sener, Silvio Savarese
2018 J jnl
CoRR
John Lambert, Ozan Sener, Silvio Savarese
2018 A* conf
NeurIPS
Riccardo Volpi, Hongseok Namkoong, Ozan Sener, John C. Duchi, Vittorio Murino, Silvio Savarese
2018 J jnl
CoRR
Riccardo Volpi, Hongseok Namkoong, Ozan Sener, John C. Duchi, Vittorio Murino, Silvio Savarese
2018 A* conf
NeurIPS
Ozan Sener, Vladlen Koltun
2018 J jnl
CoRR
Ozan Sener, Vladlen Koltun
2018 J jnl
IEEE Trans. Pattern Anal. Mach. Intell.
Chenxia Wu, Jiemi Zhang, Ozan Sener, Bart Selman, Silvio Savarese, Ashutosh Saxena
2017 J jnl
CoRR
Ozan Sener, Silvio Savarese
2017 conf
3DV
Rachel Luo, Ozan Sener, Silvio Savarese
2017 Misc conf
CoRL
Trevor Standley, Ozan Sener, Dawn Chen, Silvio Savarese
2016 A* conf
CVPR
Iro Armeni, Ozan Sener, Amir R. Zamir, Helen Jiang, Ioannis K. Brilakis, Martin Fischer, Silvio Savarese
2016 conf
NIPS
Ozan Sener, Hyun Oh Song, Ashutosh Saxena, Silvio Savarese
2016 J jnl
CoRR
Ozan Sener, Amir Roshan Zamir, Chenxia Wu, Silvio Savarese, Ashutosh Saxena
2016 J jnl
CoRR
Ozan Sener, Hyun Oh Song, Ashutosh Saxena, Silvio Savarese
2016 J jnl
CoRR
Chenxia Wu, Jiemi Zhang, Ozan Sener, Bart Selman, Silvio Savarese, Ashutosh Saxena
2015 A* conf
ICCV
Ozan Sener, Amir R. Zamir, Silvio Savarese, Ashutosh Saxena
2015 J jnl
CoRR
Ozan Sener, Amir R. Zamir, Silvio Savarese, Ashutosh Saxena
2015 conf
Robotics: Science and Systems
Ozan Sener, Ashutosh Saxena
2014 J jnl
IEEE Trans. Multim.
Ozan Sener, Kemal Ugur, A. Aydin Alatan
2014 J jnl
CoRR
Ashutosh Saxena, Ashesh Jain, Ozan Sener, Aditya Jami, Dipendra Kumar Misra, Hema Swetha Koppula
2013 J jnl
CoRR
Ozan Sener, Kemal Ugur, A. Aydin Alatan
2012 conf
IMMPD@ACM Multimedia
Ozan Sener, Kemal Ugur, A. Aydin Alatan
2012 B conf
ICIP
Yagiz Aksoy, Ozan Sener, A. Aydin Alatan, Kemal Ugur
2012 conf
VIGTA@AVI
Ozan Sener, Kemal Ugur, A. Aydin Alatan
redb/extractors/macho_extractors/macho_signature.py
← Index redb/extractors/macho_extractors/macho_signature.py python
"""
MachO Code Signature Extractor using LIEF + asn1crypto

Parses LC_CODE_SIGNATURE to extract:
- Code Directory (identifier, team_id, flags, hashes)
- Entitlements (XML plist)
- X.509 Certificates from CMS/PKCS#7 signature
- Signature verification status
"""

import hashlib
import inspect
import json
import plistlib
import struct
from datetime import datetime, timezone
from typing import Any, Dict, List, Optional, Tuple

import lief

lief.disable_leak_warning()
from asn1crypto import cms, x509

from redb.extractors.enum import Tag
from redb.extractors.macho_extractor import MachOExtractor
from redb.models.dataclasses import (
    MachOCertificate,
    MachOCodeDirectory,
    MachOCodeSigningInfo,
    MachOEntitlement,
)


# Code Signature Magic Values
CSMAGIC_REQUIREMENT = 0xFADE0C00
CSMAGIC_REQUIREMENTS = 0xFADE0C01
CSMAGIC_CODEDIRECTORY = 0xFADE0C02
CSMAGIC_EMBEDDED_SIGNATURE = 0xFADE0CC0  # SuperBlob
CSMAGIC_DETACHED_SIGNATURE = 0xFADE0CC1
CSMAGIC_BLOBWRAPPER = 0xFADE0B01  # CMS Signature
CSMAGIC_EMBEDDED_ENTITLEMENTS = 0xFADE7171
CSMAGIC_EMBEDDED_ENTITLEMENTS_DER = 0xFADE7172

# Code Directory Flags
CS_FLAGS = {
    0x00000001: "CS_VALID",
    0x00000002: "CS_ADHOC",
    0x00000004: "CS_GET_TASK_ALLOW",
    0x00000008: "CS_INSTALLER",
    0x00000010: "CS_FORCED_LV",
    0x00000020: "CS_INVALID_ALLOWED",
    0x00000100: "CS_HARD",
    0x00000200: "CS_KILL",
    0x00000400: "CS_CHECK_EXPIRATION",
    0x00000800: "CS_RESTRICT",
    0x00001000: "CS_ENFORCEMENT",
    0x00002000: "CS_REQUIRE_LV",
    0x00004000: "CS_ENTITLEMENTS_VALIDATED",
    0x00008000: "CS_NVRAM_UNRESTRICTED",
    0x00010000: "CS_RUNTIME",  # Hardened Runtime
    0x00020000: "CS_LINKER_SIGNED",
}

# Hash Types
HASH_TYPES = {
    0: "NO_HASH",
    1: "SHA1",
    2: "SHA256",
    3: "SHA256_TRUNCATED",
    4: "SHA384",
    5: "SHA512",
}

# Slot Types (used in SuperBlob index)
CSSLOT_CODEDIRECTORY = 0  # Primary Code Directory
CSSLOT_INFOSLOT = 1
CSSLOT_REQUIREMENTS = 2
CSSLOT_RESOURCEDIR = 3
CSSLOT_APPLICATION = 4
CSSLOT_ENTITLEMENTS = 5
CSSLOT_DER_ENTITLEMENTS = 7
CSSLOT_SIGNATURESLOT = 0x10000  # CMS Signature
CSSLOT_ALTERNATE_CODEDIRECTORIES = 0x1000  # First alternate CD (0x1000, 0x1001, ...)


class MachOSignatureExtractor(MachOExtractor):
    """
    Extracts code signature information from Mach-O binaries using LIEF.
    Parses certificates using asn1crypto for full X.509 details.
    """

    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_signature"
        self.log.debug(inspect.currentframe().f_code.co_name)
        self._lief_binary = None
        self._lief_fat = None

    def tag(self):
        return [
            Tag.MACHO_SIGNATURE.value,
            Tag.MACHO_CODE_DIRECTORY.value,
            Tag.MACHO_CERTIFICATE.value,
            Tag.MACHO_ENTITLEMENTS.value
        ]

    def _get_lief_binary(self, arch_index: int = 0) -> Optional[lief.MachO.Binary]:
        """Get LIEF binary for a specific architecture index."""
        try:
            if self._lief_fat is None:
                config = lief.MachO.ParserConfig()
                config.parse_dyld_exports = False
                config.parse_dyld_bindings = False
                config.parse_dyld_rebases = False
                self._lief_fat = lief.MachO.parse(self.filepath, config)

            if self._lief_fat is None:
                return None

            if arch_index < self._lief_fat.size:
                return self._lief_fat.at(arch_index)
            return None
        except Exception as e:
            self.log.error(f"Error parsing MachO with LIEF: {e}")
            return None

    def _parse_superblob(self, data: bytes) -> Dict[int, bytes]:
        """
        Parse the SuperBlob structure to extract individual blobs.

        SuperBlob structure:
        - magic: uint32 (0xfade0cc0)
        - length: uint32
        - count: uint32
        - index[count]: (type: uint32, offset: uint32)
        - blobs...

        Returns dict keyed by slot type (not magic), so we can handle
        multiple Code Directories (primary at slot 0, alternates at 0x1000+).
        """
        blobs = {}
        if len(data) < 12:
            return blobs

        magic, length, count = struct.unpack(">III", data[:12])

        if magic != CSMAGIC_EMBEDDED_SIGNATURE:
            self.log.warning(f"Unexpected SuperBlob magic: {hex(magic)}")
            return blobs

        # Parse blob index
        offset = 12
        blob_index = []
        for _ in range(count):
            if offset + 8 > len(data):
                break
            slot_type, blob_offset = struct.unpack(">II", data[offset:offset + 8])
            blob_index.append((slot_type, blob_offset))
            offset += 8

        # Extract each blob, keyed by slot type
        for slot_type, blob_offset in blob_index:
            if blob_offset + 8 > len(data):
                continue
            blob_magic, blob_length = struct.unpack(">II", data[blob_offset:blob_offset + 8])
            if blob_offset + blob_length <= len(data):
                blobs[slot_type] = data[blob_offset:blob_offset + blob_length]

        return blobs

    def _parse_code_directory(self, cd_data: bytes) -> Optional[MachOCodeDirectory]:
        """
        Parse CodeDirectory blob.

        CodeDirectory structure:
        - magic: uint32 (0xfade0c02)
        - length: uint32
        - version: uint32
        - flags: uint32
        - hashOffset: uint32
        - identOffset: uint32
        - nSpecialSlots: uint32
        - nCodeSlots: uint32
        - codeLimit: uint32
        - hashSize: uint8
        - hashType: uint8
        - platform: uint8
        - pageSize: uint8
        - spare2: uint32
        - scatterOffset: uint32 (v >= 0x20100)
        - teamOffset: uint32 (v >= 0x20200)
        ...
        """
        if len(cd_data) < 44:
            return None

        try:
            magic, length, version, flags = struct.unpack(">IIII", cd_data[:16])

            if magic != CSMAGIC_CODEDIRECTORY:
                return None

            hash_offset, ident_offset = struct.unpack(">II", cd_data[16:24])
            n_special_slots, n_code_slots, code_limit = struct.unpack(">III", cd_data[24:36])
            hash_size, hash_type, platform, page_size_log2 = struct.unpack(">BBBB", cd_data[36:40])

            # Extract identifier string
            identifier = None
            if ident_offset > 0 and ident_offset < len(cd_data):
                end = cd_data.find(b'\x00', ident_offset)
                if end > ident_offset:
                    identifier = cd_data[ident_offset:end].decode('utf-8', errors='replace')

            # Extract team ID (version >= 0x20200)
            team_id = None
            if version >= 0x20200 and len(cd_data) >= 52:
                team_offset = struct.unpack(">I", cd_data[48:52])[0]
                if team_offset > 0 and team_offset < len(cd_data):
                    end = cd_data.find(b'\x00', team_offset)
                    if end > team_offset:
                        team_id = cd_data[team_offset:end].decode('utf-8', errors='replace')

            # Parse flags
            flags_str = [name for flag, name in CS_FLAGS.items() if flags & flag]

            # Calculate CD hash
            cd_hash = hashlib.sha256(cd_data).hexdigest()

            return MachOCodeDirectory(
                identifier=identifier,
                team_id=team_id,
                flags=flags,
                cd_hash=cd_hash,
            )
        except Exception as e:
            self.log.error(f"Error parsing CodeDirectory: {e}")
            return None

    def _parse_entitlements(self, ent_data: bytes) -> Optional[Dict]:
        """
        Parse Entitlements blob (XML plist).

        Returns parsed entitlements dict.
        """
        if len(ent_data) < 8:
            return None

        try:
            magic, length = struct.unpack(">II", ent_data[:8])

            # Only accept XML plist magic - DER requires separate parser
            if magic != CSMAGIC_EMBEDDED_ENTITLEMENTS:
                return None

            # Extract plist data (after header)
            plist_data = ent_data[8:]

            # Parse plist
            try:
                entitlements = plistlib.loads(plist_data)
                return entitlements
            except Exception:
                # Try to strip null bytes
                plist_data = plist_data.rstrip(b'\x00')
                entitlements = plistlib.loads(plist_data)
                return entitlements

        except Exception as e:
            self.log.debug(f"Error parsing entitlements: {e}")
            return None

    def _parse_entitlements_der(self, ent_data: bytes) -> Optional[Dict]:
        """Best-effort parse of DER-encoded entitlements.

        DER-only binaries are rare (standard codesign embeds both XML and DER).
        Uses a layered approach: structured ASN.1 first, string extraction fallback.
        """
        if len(ent_data) < 8:
            return None

        try:
            magic, length = struct.unpack(">II", ent_data[:8])
            if magic != CSMAGIC_EMBEDDED_ENTITLEMENTS_DER:
                return None

            der_data = ent_data[8:]

            # Layer 1: Try structured ASN.1 parsing via asn1crypto
            try:
                from asn1crypto import core

                entitlements = {}
                seq = core.Sequence.load(der_data)
                for item in seq:
                    try:
                        if len(item) >= 2:
                            key = str(item[0].native)
                            val_element = item[1]
                            tag = val_element.tag
                            if tag == 0:      # BOOLEAN
                                entitlements[key] = val_element.contents != b'\x00'
                            elif tag == 1:    # UTF8String
                                entitlements[key] = val_element.native
                            elif tag == 2:    # INTEGER
                                entitlements[key] = val_element.native
                            elif tag == 3:    # SET OF (array of strings)
                                entitlements[key] = [str(v.native) for v in val_element]
                            else:
                                entitlements[key] = val_element.native
                    except Exception:
                        continue
                if entitlements:
                    return entitlements
            except Exception as e:
                self.log.debug(f"ASN.1 structured parse failed, trying string extraction: {e}")

            # Layer 2: Regex extraction of known entitlement key strings from raw DER
            # Gets keys but not typed values — still useful for detection/triage
            import re
            text = der_data.decode('utf-8', errors='ignore')
            keys = re.findall(
                r'(com\.apple\.[a-zA-Z0-9._-]+'
                r'|application-identifier'
                r'|get-task-allow'
                r'|platform-application'
                r'|team-identifier'
                r'|keychain-access-groups)',
                text
            )
            if keys:
                # Deduplicate while preserving order
                seen = set()
                entitlements = {}
                for key in keys:
                    if key not in seen:
                        seen.add(key)
                        entitlements[key] = True  # Assume boolean (most common type)
                self.log.info(
                    f"DER entitlements: ASN.1 parse failed, extracted {len(entitlements)} "
                    f"keys via string matching (values defaulted to True)"
                )
                return entitlements

            return None

        except Exception as e:
            self.log.debug(f"Error parsing DER entitlements: {e}")
            return None

    def _parse_cms_signature(self, cms_data: bytes) -> Tuple[List[MachOCertificate], Optional[str], bool]:
        """
        Parse CMS/PKCS#7 signature blob to extract certificates.

        Returns tuple of (certificates_list, signing_time, is_verified).
        """
        certificates = []
        signing_time = None
        has_cms_signature = False

        if len(cms_data) < 8:
            return certificates, signing_time, has_cms_signature

        try:
            magic, length = struct.unpack(">II", cms_data[:8])

            if magic != CSMAGIC_BLOBWRAPPER:
                return certificates, signing_time, has_cms_signature

            # CMS data starts after the blob header
            der_data = cms_data[8:]

            # Parse CMS ContentInfo
            content_info = cms.ContentInfo.load(der_data)

            if content_info['content_type'].native != 'signed_data':
                return certificates, signing_time, is_verified

            signed_data = content_info['content']

            # Extract certificates
            if signed_data['certificates']:
                cert_order = 0
                for cert_choice in signed_data['certificates']:
                    try:
                        if cert_choice.name == 'certificate':
                            cert = cert_choice.chosen
                            macho_cert = self._extract_certificate_info(cert, cert_order)
                            if macho_cert:
                                certificates.append(macho_cert)
                                cert_order += 1
                    except Exception as e:
                        self.log.debug(f"Error parsing certificate: {e}")
                        continue

            # Determine certificate types (leaf, intermediate, root)
            self._classify_certificates(certificates)

            # Extract signing time from signer info
            if signed_data['signer_infos']:
                for signer_info in signed_data['signer_infos']:
                    if signer_info['signed_attrs']:
                        for attr in signer_info['signed_attrs']:
                            if attr['type'].native == 'signing_time':
                                signing_time = attr['values'][0].native
                                if isinstance(signing_time, datetime):
                                    signing_time = signing_time.strftime("%Y-%m-%d %H:%M:%S")
                                break

            # Note: This only indicates presence of CMS signature structure, not
            # cryptographic verification. Full verification would require checking
            # against Apple's CA chain.
            has_cms_signature = len(certificates) > 0

        except Exception as e:
            self.log.error(f"Error parsing CMS signature: {e}")

        return certificates, signing_time, has_cms_signature

    def _extract_certificate_info(self, cert: x509.Certificate, order: int) -> Optional[MachOCertificate]:
        """Extract certificate information from an X.509 certificate."""
        try:
            tbs = cert['tbs_certificate']

            # Serial number
            serial = tbs['serial_number'].native
            serial_hex = format(serial, 'x').upper()

            # Subject and Issuer
            subject = self._format_name(tbs['subject'])
            issuer = self._format_name(tbs['issuer'])

            # Extract common name, organization, and OU from subject
            common_name = None
            organization = None
            organizational_unit = None
            try:
                for rdn in tbs['subject'].chosen:
                    for attr in rdn:
                        oid = attr['type'].native
                        value = attr['value'].native
                        if oid == 'common_name':
                            common_name = value
                        elif oid == 'organization_name':
                            organization = value
                        elif oid == 'organizational_unit_name':
                            organizational_unit = value
            except Exception:
                pass

            # Validity
            validity = tbs['validity']
            valid_from = validity['not_before'].native
            valid_to = validity['not_after'].native

            if isinstance(valid_from, datetime):
                valid_from = valid_from.strftime("%Y-%m-%d %H:%M:%S")
            if isinstance(valid_to, datetime):
                valid_to = valid_to.strftime("%Y-%m-%d %H:%M:%S")

            # Algorithm
            algorithm = tbs['signature']['algorithm'].native

            # Thumbprint (SHA-1 - industry standard for certificate thumbprints)
            cert_der = cert.dump()
            thumbprint = hashlib.sha1(cert_der).hexdigest().upper()

            return MachOCertificate(
                subject=subject,
                issuer=issuer,
                serial_number=serial_hex,
                not_before=valid_from,
                not_after=valid_to,
                thumbprint=thumbprint,
                certificate_type="unknown",  # Will be classified later
                order=order,
                algorithm=algorithm,
                common_name=common_name,
                organization=organization,
                organizational_unit=organizational_unit,
            )
        except Exception as e:
            self.log.error(f"Error extracting certificate info: {e}")
            return None

    def _format_name(self, name) -> str:
        """Format X.509 Name as a readable string."""
        try:
            parts = []
            for rdn in name.chosen:
                for attr in rdn:
                    oid = attr['type'].native
                    value = attr['value'].native
                    # Map common OIDs to abbreviations
                    oid_map = {
                        'common_name': 'CN',
                        'organization_name': 'O',
                        'organizational_unit_name': 'OU',
                        'country_name': 'C',
                        'state_or_province_name': 'ST',
                        'locality_name': 'L',
                        'email_address': 'E',
                        'user_id': 'UID',
                    }
                    abbrev = oid_map.get(oid, oid)
                    parts.append(f"{abbrev}={value}")
            return ", ".join(parts)
        except Exception:
            return str(name.human_friendly) if hasattr(name, 'human_friendly') else str(name)

    def _classify_certificates(self, certificates: List[MachOCertificate]):
        """
        Classify certificates as leaf, intermediate, or root using
        chain relationships:
        1. Root: self-signed (subject == issuer)
        2. Intermediate: issued another cert in the chain
        3. Leaf: everything else (end-entity)
        """
        if not certificates:
            return

        for cert in certificates:
            if cert.subject == cert.issuer:
                cert.certificate_type = "root"
            # Check if this cert issued any other cert in the chain
            elif any(c.issuer == cert.subject and c != cert for c in certificates):
                cert.certificate_type = "intermediate"
            else:
                cert.certificate_type = "leaf"

    def _extract_code_signature(self, arch_index: int = 0, arch_name: str = None) -> Optional[MachOCodeSigningInfo]:
        """Extract code signature information for a specific architecture."""
        self.log.debug(f"Extracting code signature for arch index {arch_index}")

        binary = self._get_lief_binary(arch_index)
        if binary is None:
            return None

        # Check if binary has code signature
        if not binary.has_code_signature:
            return MachOCodeSigningInfo(
                _id=self.sha256,
                signing_type="unsigned",
                has_signature=False,
                number_of_certificates=0,
                arch_identifier=arch_name,
            )

        # Get raw code signature data
        code_sig = binary.code_signature
        if code_sig is None:
            return None

        # LIEF's code_sig.data only returns the load command, not the actual signature
        # We need to read the signature data directly from the file
        # For FAT binaries, data_offset is relative to the slice, not the file
        sig_data = None
        try:
            with open(self.filepath, 'rb') as f:
                # fat_offset is 0 for single-arch binaries, slice offset for FAT
                file_offset = code_sig.data_offset + binary.fat_offset
                f.seek(file_offset)
                sig_data = f.read(code_sig.data_size)
        except Exception as e:
            self.log.error(f"Error reading code signature data from file: {e}")
            return None

        if not sig_data:
            return None

        # Parse SuperBlob to get individual blobs (keyed by slot type)
        blobs = self._parse_superblob(sig_data)

        # Parse all Code Directories (primary + alternates)
        code_directories = []

        # Primary Code Directory at slot 0
        if CSSLOT_CODEDIRECTORY in blobs:
            cd = self._parse_code_directory(blobs[CSSLOT_CODEDIRECTORY])
            if cd:
                cd.slot_type = CSSLOT_CODEDIRECTORY
                code_directories.append(cd)

        # Alternate Code Directories at slots 0x1000, 0x1001, ...
        for slot_type in sorted(blobs.keys()):
            if slot_type >= CSSLOT_ALTERNATE_CODEDIRECTORIES and slot_type < CSSLOT_SIGNATURESLOT:
                cd = self._parse_code_directory(blobs[slot_type])
                if cd:
                    cd.slot_type = slot_type
                    code_directories.append(cd)

        # Use primary CD (or first available) for signing info
        primary_cd = code_directories[0] if code_directories else None

        # Parse Entitlements - prefer XML plist, fall back to DER for edge cases
        entitlements = None
        if CSSLOT_ENTITLEMENTS in blobs:
            entitlements = self._parse_entitlements(blobs[CSSLOT_ENTITLEMENTS])
        if entitlements is None and CSSLOT_DER_ENTITLEMENTS in blobs:
            # DER-only binary (rare — non-standard signing tool like ldid)
            self.log.warning("Only DER entitlements found, no XML plist slot")
            entitlements = self._parse_entitlements_der(blobs[CSSLOT_DER_ENTITLEMENTS])

        # Parse CMS Signature (certificates)
        certificates = []
        signing_time = None
        has_cms_signature = False

        if CSSLOT_SIGNATURESLOT in blobs:
            certificates, signing_time, has_cms_signature = self._parse_cms_signature(blobs[CSSLOT_SIGNATURESLOT])

        # Determine signing type
        signing_type = "unsigned"
        if primary_cd:
            if primary_cd.flags and (primary_cd.flags & 0x00000002):  # CS_ADHOC
                signing_type = "ad-hoc"
            elif len(certificates) > 0:
                signing_type = "certificate"
            elif primary_cd.identifier:
                # Has CodeDirectory but no CMS = ad-hoc
                signing_type = "ad-hoc"

        # Check for hardened runtime and library validation flags
        has_hardened_runtime = False
        has_library_validation = False
        if primary_cd and primary_cd.flags:
            has_hardened_runtime = bool(primary_cd.flags & 0x00010000)  # CS_RUNTIME
            has_library_validation = bool(primary_cd.flags & 0x00002000)  # CS_REQUIRE_LV

        return MachOCodeSigningInfo(
            _id=self.sha256,
            signing_type=signing_type,
            has_signature=has_cms_signature,
            number_of_certificates=len(certificates),
            code_directories=code_directories,
            entitlements=entitlements,
            x509_certificates=certificates,
            date_signed=signing_time,
            arch_identifier=arch_name,
            has_hardened_runtime=has_hardened_runtime,
            has_library_validation=has_library_validation,
        )

    def extract(self) -> Optional[Any]:
        """Extract code signature information from the Mach-O binary."""
        self.log.debug(inspect.currentframe().f_code.co_name)

        try:
            # Get LIEF FAT binary to check architecture count
            config = lief.MachO.ParserConfig()
            config.parse_dyld_exports = False
            config.parse_dyld_bindings = False
            config.parse_dyld_rebases = False
            self._lief_fat = lief.MachO.parse(self.filepath, config)

            if self._lief_fat is None:
                self.log.error("Failed to parse MachO with LIEF")
                return None

            # Get architecture names from machofile for consistency
            arch_names = []
            if self.macho:
                try:
                    arch_names = self.macho.get_architectures()
                except Exception:
                    pass

            # If no arch names from machofile, generate them
            if not arch_names:
                arch_names = [f"arch_{i}" for i in range(self._lief_fat.size)]

            if self._lief_fat.size > 1:
                # FAT/Universal binary - extract for each architecture
                results = []
                for i in range(self._lief_fat.size):
                    arch_name = arch_names[i] if i < len(arch_names) else f"arch_{i}"
                    signature = self._extract_code_signature(i, arch_name)
                    if signature:
                        results.append(signature)
                return results if results else None
            else:
                # Single architecture
                arch_name = arch_names[0] if arch_names else None
                return self._extract_code_signature(0, arch_name)

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

    def prepare_export_data(self, exporter_type: str) -> Any:
        """Prepare data for export to Elasticsearch or ClickHouse."""
        self.log.debug(inspect.currentframe().f_code.co_name)

        if exporter_type == "ElasticsearchExporter":
            return self.extract()

        elif exporter_type == "ClickHouseExporter":
            result = self.extract()
            if result is None:
                return None

            # Normalize to list
            signatures = result if isinstance(result, list) else [result]

            current_time = datetime.now(timezone.utc)

            # Prepare signature data
            signatures_data = []
            certificates_data = []
            entitlements_data = []

            for sig in signatures:
                if sig is None:
                    continue

                # Get architecture-specific hash if available
                arch_sha256 = self.sha256

                # If FAT binary, try to get arch-specific sha256
                if self.macho and sig.arch_identifier:
                    try:
                        arch_info = self.macho.get_general_info(arch=sig.arch_identifier)
                        if arch_info:
                            arch_sha256 = arch_info.get('SHA256', self.sha256)
                    except Exception as e:
                        self.log.debug(f"Could not get arch-specific info: {e}")

                # Get primary CD fields for signatures table
                primary_cd = sig.code_directories[0] if sig.code_directories else None
                cd_identifier = primary_cd.identifier if primary_cd else None
                cd_team_id = primary_cd.team_id if primary_cd else None
                cd_flags = primary_cd.flags if primary_cd else None
                cd_hash = primary_cd.cd_hash if primary_cd else None

                signatures_data.append([
                    arch_sha256,
                    sig.signing_type,
                    sig.has_signature,
                    sig.number_of_certificates,
                    cd_identifier,
                    cd_team_id,
                    cd_flags,
                    cd_hash,
                    sig.has_hardened_runtime,
                    sig.has_library_validation,
                    sig.date_signed,
                    current_time,
                ])

                # Prepare certificate data
                if sig.x509_certificates:
                    for cert in sig.x509_certificates:
                        certificates_data.append([
                            arch_sha256,
                            cert.certificate_type,
                            cert.algorithm,
                            cert.issuer,
                            cert.subject,
                            cert.serial_number,
                            cert.thumbprint,
                            datetime.strptime(cert.not_before, "%Y-%m-%d %H:%M:%S") if cert.not_before else None,
                            datetime.strptime(cert.not_after, "%Y-%m-%d %H:%M:%S") if cert.not_after else None,
                            current_time,
                        ])

                # Prepare entitlements data
                if sig.entitlements:
                    for ent_key, ent_value in sig.entitlements.items():
                        # Determine type and set appropriate value columns
                        if isinstance(ent_value, bool):
                            ent_type = 'boolean'
                            value_bool = 1 if ent_value else 0
                            value_string = None
                            value_array = []
                        elif isinstance(ent_value, list):
                            ent_type = 'array'
                            value_bool = None
                            value_string = None
                            # Convert all list items to strings
                            value_array = [str(v) for v in ent_value]
                        else:
                            ent_type = 'string'
                            value_bool = None
                            value_string = str(ent_value)
                            value_array = []

                        entitlements_data.append([
                            arch_sha256,
                            ent_key,
                            ent_type,
                            value_bool,
                            value_string,
                            value_array,
                            current_time,
                        ])

            return {
                'multi_table': True,
                'signatures': {
                    'table': 'redb_macho_signatures',
                    'data': signatures_data,
                    'column_names': [
                        'sha256',
                        'signing_type', 'has_signature', 'number_of_certificates',
                        'cd_identifier', 'cd_team_id', 'cd_flags', 'cd_hash',
                        'has_hardened_runtime', 'has_library_validation',
                        'date_signed', 'analysis_date'
                    ],
                    'column_type_names': [
                        'FixedString(64)',
                        "Enum8('unsigned' = 0, 'ad-hoc' = 1, 'certificate' = 2)", 'UInt8', 'UInt32',
                        'Nullable(String)', 'Nullable(String)', 'Nullable(UInt32)', 'Nullable(String)',
                        'UInt8', 'UInt8',
                        'Nullable(DateTime64(3, \'UTC\'))', 'DateTime64(3, \'UTC\')'
                    ]
                },
                'certificates': {
                    'table': 'redb_macho_certificates',
                    'data': certificates_data,
                    'column_names': [
                        'sha256', 'certificate_type', 'certificate_algorithm',
                        'certificate_issuer', 'certificate_subject', 'certificate_serial_number',
                        'certificate_thumbprint', 'certificate_valid_from', 'certificate_valid_to',
                        'analysis_date'
                    ],
                    'column_type_names': [
                        'FixedString(64)',
                        "Enum8('leaf' = 1, 'intermediate' = 2, 'root' = 3)", 'LowCardinality(String)',
                        'String', 'String', 'String', 'FixedString(40)',
                        'DateTime64(3, \'UTC\')', 'DateTime64(3, \'UTC\')', 'DateTime64(3, \'UTC\')'
                    ]
                },
                'entitlements': {
                    'table': 'redb_macho_entitlements',
                    'data': entitlements_data,
                    'column_names': [
                        'sha256', 'entitlement_key', 'entitlement_type',
                        'value_bool', 'value_string', 'value_array',
                        'analysis_date'
                    ],
                    'column_type_names': [
                        'FixedString(64)', 'LowCardinality(String)',
                        "Enum8('boolean' = 1, 'string' = 2, 'array' = 3)",
                        'Nullable(UInt8)', 'Nullable(String)', 'Array(String)',
                        'DateTime64(3, \'UTC\')'
                    ]
                }
            }

        return None

    def get_clickhouse_table(self) -> str:
        """Return primary ClickHouse table name."""
        return "redb_macho_signatures"

    def get_clickhouse_tables(self) -> Dict[str, str]:
        """Return all ClickHouse tables for multi-table export."""
        return {
            'signatures': 'redb_macho_signatures',
            'certificates': 'redb_macho_certificates',
            'entitlements': 'redb_macho_entitlements'
        }