Ralf Cordes

20 papers B 1Misc 2Journal 4Unranked 11
YearRankTypeTitle / Venue / Authors
1998 conf
GI Jahrestagung
Ralf Cordes
1994 conf
IWACA
Rüdiger Strack, Ralf Cordes, Dale C. Sutcliffe
1992 J jnl
Comput. Commun. Rev.
Ralf Cordes, Hauke Peyn, Thomas Kummerow, Thomas Töpperwien, Thomas Weidenfeller
1992 ed.
Hypertext und Hypermedia
Ralf Cordes, Norbert A. Streitz
1992 conf
Hypertext und Hypermedia
Thomas Weidenfeller, Ralf Cordes
1992 J jnl
Datenbank Rundbr.
Hauke Peyn, A. Spahn, Stephan Euler, Ralf Cordes, Joachim Zinke
1991 conf
GI Jahrestagung
M. Weiss, Arek Lesch, Ralf Cordes, Karl-Heinz Jerke, Horst Rößler, Peter Szabó
1991 B conf
NOSSDAV
Ralf Cordes, Dieter Wybranietz, Rolf Vautz
1991 conf
GI-Fachgespräch über Rechenzentren
Ralf Cordes, G. Leicher
1990 conf
Hypertext und Hypermedia
Klaus Süllow, Ralf Cordes
1990 J jnl
Wirtschaftsinf.
Klaus Süllow, Ralf Cordes, Ingeborg Sell, Johannes-Henrich Kirchner
1990 conf
Hypertext und Hypermedia
Martin Hofmann, Ralf Cordes, Horst Langendörfer, E. Lübben, Hauke Peyn, Klaus Süllow, Thomas Töpperwien
1989 Misc conf
BTW
Martin Hofmann, Ralf Cordes, Horst Langendörfer
1989 conf
GI Jahrestagung (2)
Ralf Cordes, Klaus Süllow
1989 J jnl
Inform. Spektrum
Martin Hofmann, Ralf Cordes, Horst Langendörfer
1989
Ralf Cordes
1988 conf
RIAO
Ralf Cordes, Rüdiger Buck-Emden, Horst Langendörfer
1987 conf
GI Jahrestagung
Rüdiger Buck-Emden, Ralf Cordes, Horst Langendörfer
1987 Misc conf
BTW
Ralf Cordes, Rüdiger Buck-Emden, Martin Hofmann, Horst Langendörfer
1986 conf
GI Jahrestagung (2)
Horst Langendörfer, Rüdiger Buck-Emden, Ralf Cordes
redb/extractors/elf_extractors/elf_symbols.py
← Index redb/extractors/elf_extractors/elf_symbols.py python
import inspect
from datetime import datetime, timezone
from typing import Any, List, Dict

from elftools.elf.elffile import ELFFile
from elftools.common.exceptions import ELFError

from redb.extractors.enum import Tag
from redb.extractors.elf_extractor import ELFExtractor
from redb.models.dataclasses import ELFSymbol


class ELFSymbolExtractor(ELFExtractor):

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

    def _map_symbol_type(self, st_type_str: str) -> int:
        """Map symbol type string to enum value."""
        type_map = {
            'STT_NOTYPE': 0,
            'STT_OBJECT': 1,
            'STT_FUNC': 2,
            'STT_SECTION': 3,
            'STT_FILE': 4,
            'STT_COMMON': 5,
            'STT_TLS': 6
        }
        return type_map.get(st_type_str, 0)

    def _map_symbol_bind(self, st_bind_str: str) -> int:
        """Map symbol binding string to enum value."""
        bind_map = {
            'STB_LOCAL': 0,
            'STB_GLOBAL': 1,
            'STB_WEAK': 2
        }
        return bind_map.get(st_bind_str, 0)

    def _map_symbol_visibility(self, st_vis_str: str) -> int:
        """Map symbol visibility string to enum value."""
        vis_map = {
            'STV_DEFAULT': 0,
            'STV_INTERNAL': 1,
            'STV_HIDDEN': 2,
            'STV_PROTECTED': 3
        }
        return vis_map.get(st_vis_str, 0)

    def _extract_symbol_data(self, symbol, is_dynamic: bool = False) -> Dict:
        """Extract data from a single symbol."""
        try:
            # Get symbol name (handle empty names)
            symbol_name = symbol.name if symbol.name else f"<unnamed_{symbol.entry.get('st_name', 0)}>"

            # Get symbol properties
            symbol_value = symbol.entry.get('st_value', 0)
            symbol_size = symbol.entry.get('st_size', 0)

            # Handle section index - can be integer or special string like 'SHN_UNDEF'
            st_shndx_raw = symbol.entry.get('st_shndx', 0)
            if isinstance(st_shndx_raw, str):
                # Map special section index strings to integers
                shndx_map = {
                    'SHN_UNDEF': 0,
                    'SHN_ABS': 65521,  # 0xFFF1
                    'SHN_COMMON': 65522,  # 0xFFF2
                    'SHN_XINDEX': 65535,  # 0xFFFF
                }
                symbol_section_index = shndx_map.get(st_shndx_raw, 0)
                symbol_section_index_str = st_shndx_raw.replace('SHN_', '') if st_shndx_raw.startswith('SHN_') else st_shndx_raw
            else:
                symbol_section_index = st_shndx_raw
                symbol_section_index_str = str(st_shndx_raw)

            # Get symbol type and map to enum
            st_type_str = symbol.entry.get('st_info', {}).get('type', 'STT_NOTYPE')
            symbol_type_enum = self._map_symbol_type(st_type_str)
            symbol_type_str = st_type_str.replace('STT_', '') if st_type_str.startswith('STT_') else st_type_str

            # Get symbol binding and map to enum
            st_bind_str = symbol.entry.get('st_info', {}).get('bind', 'STB_LOCAL')
            symbol_bind_enum = self._map_symbol_bind(st_bind_str)
            symbol_bind_str = st_bind_str.replace('STB_', '') if st_bind_str.startswith('STB_') else st_bind_str

            # Get symbol visibility and map to enum
            st_vis_str = symbol.entry.get('st_other', {}).get('visibility', 'STV_DEFAULT')
            symbol_visibility_enum = self._map_symbol_visibility(st_vis_str)
            symbol_visibility_str = st_vis_str.replace('STV_', '') if st_vis_str.startswith('STV_') else st_vis_str

            return ELFSymbol(
                symbol_name=symbol_name,
                symbol_value=symbol_value,
                symbol_size=symbol_size,
                symbol_type=symbol_type_enum,
                symbol_type_str=symbol_type_str,
                symbol_bind=symbol_bind_enum,
                symbol_bind_str=symbol_bind_str,
                symbol_visibility=symbol_visibility_enum,
                symbol_visibility_str=symbol_visibility_str,
                symbol_section_index=symbol_section_index,
                symbol_section_index_str=symbol_section_index_str,
                is_dynamic=1 if is_dynamic else 0
            )

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

    def _extract_symbols_from_section(self, elf, section_name: str, is_dynamic: bool = False) -> List[Dict]:
        """Extract symbols from a specific symbol table section."""
        symbols = []

        try:
            section = elf.get_section_by_name(section_name)
            if not section:
                self.log.debug(f"No {section_name} section found")
                return symbols

            if not hasattr(section, 'iter_symbols'):
                self.log.debug(f"Section {section_name} is not a symbol table")
                return symbols

            # Iterate through symbols in the section with per-symbol error handling
            for symbol_index, symbol in enumerate(section.iter_symbols()):
                try:
                    symbol_data = self._extract_symbol_data(symbol, is_dynamic)
                    if symbol_data:
                        symbols.append(symbol_data)
                except Exception as e:
                    self.log.warning(f"Error processing symbol {symbol_index} in {section_name}: {e}")
                    # Continue with other symbols

        except Exception as e:
            self.log.error(f"Error extracting symbols from {section_name}: {e}")

        return symbols

    def tag(self):
        return Tag.ELF_SYMBOLS.value if hasattr(Tag, 'ELF_SYMBOLS') else "elf_symbols"

    def extract(self):
        try:
            self.log.debug(inspect.currentframe().f_code.co_name)

            def extract_data(elf):
                all_symbols = []

                # Extract static symbols from .symtab with individual error handling
                try:
                    static_symbols = self._extract_symbols_from_section(elf, '.symtab', is_dynamic=False)
                    all_symbols.extend(static_symbols)
                    self.log.debug(f"Extracted {len(static_symbols)} static symbols from .symtab")
                except Exception as e:
                    self.log.warning(f"Error extracting static symbols from .symtab: {e}")

                # Extract dynamic symbols from .dynsym with individual error handling
                try:
                    dynamic_symbols = self._extract_symbols_from_section(elf, '.dynsym', is_dynamic=True)
                    all_symbols.extend(dynamic_symbols)
                    self.log.debug(f"Extracted {len(dynamic_symbols)} dynamic symbols from .dynsym")
                except Exception as e:
                    self.log.warning(f"Error extracting dynamic symbols from .dynsym: {e}")

                return all_symbols

            if not self._is_elf_file():
                return None

            result = self._with_elf_file(extract_data)
            if result is None:
                return None

            self.elf_symbols = result
            return self.elf_symbols

        except Exception as e:
            self.log.error(f"Error extracting ELF symbols {self.hash.sha256}: {e}")
            return None

    def prepare_export_data(self, exporter_type: str) -> Any:
        self.log.debug(inspect.currentframe().f_code.co_name)

        if exporter_type == "ElasticsearchExporter":
            return self.elf_symbols
        elif exporter_type == "ClickHouseExporter":
            try:
                # Return valid empty structure if no symbols (e.g., stripped binary)
                # None is reserved for actual errors

                # Prepare data arrays for all symbols
                data = []
                current_time = datetime.now(timezone.utc)
                for symbol in self.elf_symbols:
                    row = [
                        self.sha256,
                        self.md5,
                        self.sha1,
                        symbol.symbol_name,
                        symbol.symbol_value,
                        symbol.symbol_size,
                        symbol.symbol_type,
                        symbol.symbol_type_str,
                        symbol.symbol_bind,
                        symbol.symbol_bind_str,
                        symbol.symbol_visibility,
                        symbol.symbol_visibility_str,
                        symbol.symbol_section_index,
                        symbol.symbol_section_index_str,
                        symbol.is_dynamic,
                        current_time
                    ]
                    data.append(row)

                column_names = [
                    'sha256', 'md5', 'sha1',
                    'symbol_name', 'symbol_value', 'symbol_size',
                    'symbol_type', 'symbol_type_str',
                    'symbol_bind', 'symbol_bind_str',
                    'symbol_visibility', 'symbol_visibility_str',
                    'symbol_section_index', 'symbol_section_index_str', 'is_dynamic',
                    'analysis_date'
                ]

                column_type_names = [
                    'FixedString(64)', 'FixedString(32)', 'FixedString(40)',
                    'LowCardinality(String)', 'UInt64', 'UInt64',
                    "Enum8('NOTYPE'=0, 'OBJECT'=1, 'FUNC'=2, 'SECTION'=3, 'FILE'=4, 'COMMON'=5, 'TLS'=6)",
                    'LowCardinality(String)',
                    "Enum8('LOCAL'=0, 'GLOBAL'=1, 'WEAK'=2)",
                    'LowCardinality(String)',
                    "Enum8('DEFAULT'=0, 'INTERNAL'=1, 'HIDDEN'=2, 'PROTECTED'=3)",
                    'LowCardinality(String)',
                    'UInt16', 'LowCardinality(String)', 'UInt8',
                    'DateTime64(3, \'UTC\')'
                ]

                if not data:
                    return None

                return (data, column_names, column_type_names)

            except Exception as e:
                self.log.error(f"Error preparing export data: {e}")
                raise

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