Vasileios Kalantzis

36 papers A* 3A 2Misc 2Journal 25Unranked 4
YearRankTypeTitle / Venue / Authors
2026 J jnl
CoRR
Qitong Wang, Mohammed J. Zaki, Georgios Kollias, Vasileios Kalantzis
2025 conf
ACL (Findings)
Qitong Wang, Mohammed J. Zaki, Georgios Kollias, Vasileios Kalantzis
2025 J jnl
CoRR
Qitong Wang, Mohammed J. Zaki, Georgios Kollias, Vasileios Kalantzis
2025 J jnl
CoRR
Vasileios Kalantzis, Mark S. Squillante, Chai Wah Wu
2025 J jnl
Monte Carlo Methods Appl.
Lior Horesh, Vasileios Kalantzis, Yingdong Lu, Tomasz Nowicki
2025 conf
HPEC
Vasileios Kalantzis, Mark S. Squillante, Chai Wah Wu
2025 J jnl
CoRR
Vasileios Kalantzis, Mark S. Squillante, Chai Wah Wu
2024 J jnl
SIAM J. Sci. Comput.
Tianshi Xu, Anthony P. Austin, Vasileios Kalantzis, Yousef Saad
2024 A conf
AISTATS
Vasileios Kalantzis, Shashanka Ubaru, Chai Wah Wu, Georgios Kollias, Lior Horesh
2024 J jnl
Trans. Mach. Learn. Res.
Qitong Wang, Georgios Kollias, Vasileios Kalantzis, Naoki Abe, Mohammed J. Zaki
2024 J jnl
CoRR
Vasileios Kalantzis, Mark S. Squillante, Shashanka Ubaru
2024 J jnl
SIGMETRICS Perform. Evaluation Rev.
Vasileios Kalantzis, Mark S. Squillante, Shashanka Ubaru
2024 J jnl
CoRR
Lior Horesh, Vasileios Kalantzis, Yingdong Lu, Tomasz Nowicki
2024 A* conf
ICLR
Ismail Yunus Akhalwaya, Shashanka Ubaru, Kenneth L. Clarkson, Mark S. Squillante, Vishnu Jejjala, Yang-Hui He, Kugendran Naidoo, Vasileios Kalantzis, Lior Horesh
2023 Misc conf
ICASSP
Vasileios Kalantzis, Panagiotis A. Traganitis
2023 Misc conf
ACSSC
Vasileios Kalantzis, Panagiotis A. Traganitis
2023 conf
HPEC
Vasileios Kalantzis, Mark S. Squillante, Chai Wah Wu, Anshul Gupta, Shashanka Ubaru, Tayfun Gokmen, Lior Horesh
2023 J jnl
CoRR
Chai Wah Wu, Mark S. Squillante, Vasileios Kalantzis, Lior Horesh
2022 A* conf
AAAI
Georgios Kollias, Vasileios Kalantzis, Tsuyoshi Idé, Aurélie C. Lozano, Naoki Abe
2022 J jnl
CoRR
Georgios Kollias, Vasileios Kalantzis, Tsuyoshi Idé, Aurélie C. Lozano, Naoki Abe
2022 J jnl
SIGMETRICS Perform. Evaluation Rev.
Vasileios Kalantzis, Mark S. Squillante, Shashanka Ubaru, Lior Horesh
2022 J jnl
CoRR
Paz Fink Shustin, Shashanka Ubaru, Vasileios Kalantzis, Lior Horesh, Haim Avron
2022 J jnl
CoRR
Ismail Yunus Akhalwaya, Shashanka Ubaru, Kenneth L. Clarkson, Mark S. Squillante, Vishnu Jejjala, Yang-Hui He, Kugendran Naidoo, Vasileios Kalantzis, Lior Horesh
2021 A* conf
ICML
Vasileios Kalantzis, Georgios Kollias, Shashanka Ubaru, Athanasios N. Nikolakopoulos, Lior Horesh, Kenneth L. Clarkson
2021 conf
HPEC
Vasileios Kalantzis, Anshul Gupta, Lior Horesh, Tomasz Nowicki, Mark S. Squillante, Chai Wah Wu, Tayfun Gokmen, Haim Avron
2021 J jnl
CoRR
Vasileios Kalantzis, Anshul Gupta, Lior Horesh, Tomasz Nowicki, Mark S. Squillante, Chai Wah Wu
2018 J jnl
XRDS
Vasileios Kalantzis
2018 J jnl
XRDS
Vasileios Kalantzis
2018 J jnl
XRDS
Vasileios Kalantzis
2018 J jnl
XRDS
Vasileios Kalantzis
2018 J jnl
XRDS
Vasileios Kalantzis
2017 J jnl
XRDS
Vasileios Kalantzis
2017 J jnl
XRDS
Vasileios Kalantzis
2017 J jnl
XRDS
Vasileios Kalantzis
2017 J jnl
XRDS
Vasileios Kalantzis
2016 A conf
SC
James Kestyn, Vasileios Kalantzis, Eric Polizzi, Yousef Saad
redb/extractors/macho_extractors/macho_imports.py
← Index redb/extractors/macho_extractors/macho_imports.py python
import inspect
from datetime import datetime, timezone
from typing import Any

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


class MachOImportExtractor(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_imports"
        self.log.debug(inspect.currentframe().f_code.co_name)

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

    def _extract_imports(self, arch_name=None):
        """Extract import information from the MachO binary for a specific architecture.

        Handles machofile v2026.2.4+ API where get_imported_functions() returns:
        Dict[str, List[Dict]] where each dict has {'name': str, 'sources': [str, ...]}
        """
        self.log.debug(inspect.currentframe().f_code.co_name)

        if not self.macho:
            return None

        try:
            # Get imported functions using API for specific architecture
            imported_functions = self.macho.get_imported_functions(arch=arch_name)
            if not imported_functions:
                return None

            # Keep the library→functions mapping (like PE does)
            library_names = []
            imports_with_mapping = []  # List of {library: [(name, source), ...]}

            for dylib_name, functions in imported_functions.items():
                # v2026.2.4+: dylib_name is already str, but handle bytes for compatibility
                if isinstance(dylib_name, bytes):
                    dylib_name = dylib_name.decode('utf-8', errors='replace')
                library_names.append(dylib_name)

                # Process function entries
                func_list = []
                for func_entry in functions:
                    # v2026.2.4+: func_entry is {'name': str, 'sources': [str, ...]}
                    if isinstance(func_entry, dict):
                        func_name = func_entry.get('name', '')
                        # Join sources if multiple, take first if single
                        sources = func_entry.get('sources', [])
                        import_source = sources[0] if sources else None
                        func_list.append((func_name, import_source))
                    else:
                        # Legacy format: func_entry is str or bytes
                        if isinstance(func_entry, bytes):
                            func_entry = func_entry.decode('utf-8', errors='replace')
                        func_list.append((func_entry, None))

                imports_with_mapping.append({dylib_name: func_list})

            # Count total functions
            total_functions = sum(len(list(d.values())[0]) for d in imports_with_mapping)

            # Create import dataclass with mapping preserved
            macho_import = MachOImport(
                macho_imports_total=total_functions,
                macho_import_libraryName=library_names if library_names else None,
                macho_import_functions=imports_with_mapping if imports_with_mapping else None
            )

            return macho_import

        except Exception as e:
            self.log.error(f"Error extracting MachO imports for arch {arch_name}: {e}")
            return None

    def extract(self):
        self.log.debug(inspect.currentframe().f_code.co_name)
        try:
            # Get architectures (macho is already parsed in base class)
            architectures = self.macho.get_architectures()
            if len(architectures) > 1:
                # FAT binary - return list of imports for each architecture
                results = []
                for arch_name in architectures:
                    imports = self._extract_imports(arch_name)
                    if imports:
                        imports.arch_identifier = arch_name
                        results.append(imports)
                return results
            else:
                # Single architecture - return single result
                return self._extract_imports(architectures[0] if architectures else None)
        except Exception as e:
            self.log.error(f"Error extracting MachO imports: {e}")
            return None

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

            # Get architectures (macho is already parsed in base class)
            try:
                architectures = self.macho.get_architectures()
                is_fat = len(architectures) > 1
            except Exception as e:
                self.log.error(f"Could not get architectures: {e}")
                return None

            # Flatten the data - one row per function import (like PE imports)
            data = []
            current_time = datetime.now(timezone.utc)

            # Loop through each architecture (1 for single, multiple for FAT)
            for arch_name in architectures:
                # Get architecture-specific sha256
                try:
                    arch_general_info = self.macho.get_general_info(arch=arch_name)
                    arch_header_raw = self.macho.get_macho_header(arch=arch_name)
                    arch_sha256 = arch_general_info.get('SHA256', self.sha256)
                    arch_cputype_raw = arch_header_raw.get('cputype', 0) if arch_header_raw else 0
                except Exception as e:
                    self.log.warning(f"Could not get arch-specific data for {arch_name}: {e}")
                    arch_sha256 = self.sha256
                    arch_cputype_raw = 0

                # Get imports for this architecture
                macho_import = self._extract_imports(arch_name)
                if not macho_import or not macho_import.macho_import_functions:
                    continue

                # Flatten to one row per (library, function) pair
                for lib_funcs in macho_import.macho_import_functions:
                    for lib, funcs in lib_funcs.items():
                        for func_name, import_source in funcs:
                            data.append([
                                arch_sha256,        # sha256 (arch-specific)
                                lib,                # library_name
                                func_name,          # function_name
                                import_source,      # import_source (chained_fixups, bind_opcodes, symtab)
                                current_time,       # analysis_date
                            ])

            column_names = [
                'sha256',
                'library_name', 'function_name', 'import_source',
                'analysis_date'
            ]

            if not data:
                return None

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

            return (data, column_names, column_type_names)

        return None

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