#!/usr/bin/env python3 # Copyright (c) 2014 Wladimir J. van der Laan # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. ''' A script to check that release executables only contain certain symbols and are only linked against allowed libraries. Example usage: find ../path/to/binaries -type f -executable | xargs python3 contrib/devtools/symbol-check.py ''' import subprocess import sys import os from typing import List, Optional import lief import pixie # Debian 8 (Jessie) EOL: 2020. https://wiki.debian.org/DebianReleases#Production_Releases # # - g++ version 4.9.2 (https://packages.debian.org/search?suite=jessie&arch=any&searchon=names&keywords=g%2B%2B) # - libc version 2.19 (https://packages.debian.org/search?suite=jessie&arch=any&searchon=names&keywords=libc6) # # Ubuntu 16.04 (Xenial) EOL: 2024. https://wiki.ubuntu.com/Releases # # - g++ version 5.3.1 (https://packages.ubuntu.com/search?keywords=g%2B%2B&searchon=names&suite=xenial§ion=all) # - libc version 2.23.0 (https://packages.ubuntu.com/search?keywords=libc6&searchon=names&suite=xenial§ion=all) # # CentOS 7 EOL: 2024. https://wiki.centos.org/FAQ/General # # - g++ version 4.8.5 (http://mirror.centos.org/centos/7/os/x86_64/Packages/) # - libc version 2.17 (http://mirror.centos.org/centos/7/os/x86_64/Packages/) # # Taking the minimum of these as our target. # # According to GNU ABI document (https://gcc.gnu.org/onlinedocs/libstdc++/manual/abi.html) this corresponds to: # GCC 4.8.5: GCC_4.8.0 # (glibc) GLIBC_2_17 # MAX_VERSIONS = { 'GCC': (4,8,0), 'GLIBC': { pixie.EM_386: (2,17), pixie.EM_X86_64: (2,17), pixie.EM_ARM: (2,17), pixie.EM_AARCH64:(2,17), pixie.EM_PPC64: (2,17), pixie.EM_RISCV: (2,27), }, 'LIBATOMIC': (1,0), 'V': (0,5,0), # xkb (bitcoin-qt only) } # See here for a description of _IO_stdin_used: # https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=634261#109 # Ignore symbols that are exported as part of every executable IGNORE_EXPORTS = { '_edata', '_end', '__end__', '_init', '__bss_start', '__bss_start__', '_bss_end__', '__bss_end__', '_fini', '_IO_stdin_used', 'stdin', 'stdout', 'stderr', 'environ', '_environ', '__environ', } CPPFILT_CMD = os.getenv('CPPFILT', '/usr/bin/c++filt') # Allowed NEEDED libraries ELF_ALLOWED_LIBRARIES = { # bitcoind and bitcoin-qt 'libgcc_s.so.1', # GCC base support 'libc.so.6', # C library 'libpthread.so.0', # threading 'libm.so.6', # math library 'librt.so.1', # real-time (clock) 'libatomic.so.1', 'ld-linux-x86-64.so.2', # 64-bit dynamic linker 'ld-linux.so.2', # 32-bit dynamic linker 'ld-linux-aarch64.so.1', # 64-bit ARM dynamic linker 'ld-linux-armhf.so.3', # 32-bit ARM dynamic linker 'ld64.so.1', # POWER64 ABIv1 dynamic linker 'ld64.so.2', # POWER64 ABIv2 dynamic linker 'ld-linux-riscv64-lp64d.so.1', # 64-bit RISC-V dynamic linker # bitcoin-qt only 'libxcb.so.1', # part of X11 'libxkbcommon.so.0', # keyboard keymapping 'libxkbcommon-x11.so.0', # keyboard keymapping 'libfontconfig.so.1', # font support 'libfreetype.so.6', # font parsing 'libdl.so.2' # programming interface to dynamic linker } MACHO_ALLOWED_LIBRARIES = { # bitcoind and bitcoin-qt 'libc++.1.dylib', # C++ Standard Library 'libSystem.B.dylib', # libc, libm, libpthread, libinfo # bitcoin-qt only 'AppKit', # user interface 'ApplicationServices', # common application tasks. 'Carbon', # deprecated c back-compat API 'CoreFoundation', # low level func, data types 'CoreGraphics', # 2D rendering 'CoreServices', # operating system services 'CoreText', # interface for laying out text and handling fonts. 'CoreVideo', # video processing 'Foundation', # base layer functionality for apps/frameworks 'ImageIO', # read and write image file formats. 'IOKit', # user-space access to hardware devices and drivers. 'IOSurface', # cross process image/drawing buffers 'libobjc.A.dylib', # Objective-C runtime library 'Metal', # 3D graphics 'Security', # access control and authentication 'QuartzCore', # animation } PE_ALLOWED_LIBRARIES = { 'ADVAPI32.dll', # security & registry 'IPHLPAPI.DLL', # IP helper API 'KERNEL32.dll', # win32 base APIs 'msvcrt.dll', # C standard library for MSVC 'SHELL32.dll', # shell API 'USER32.dll', # user interface 'WS2_32.dll', # sockets # bitcoin-qt only 'dwmapi.dll', # desktop window manager 'GDI32.dll', # graphics device interface 'IMM32.dll', # input method editor 'NETAPI32.dll', 'ole32.dll', # component object model 'OLEAUT32.dll', # OLE Automation API 'SHLWAPI.dll', # light weight shell API 'USERENV.dll', 'UxTheme.dll', 'VERSION.dll', # version checking 'WINMM.dll', # WinMM audio API 'WTSAPI32.dll', } class CPPFilt(object): ''' Demangle C++ symbol names. Use a pipe to the 'c++filt' command. ''' def __init__(self): self.proc = subprocess.Popen(CPPFILT_CMD, stdin=subprocess.PIPE, stdout=subprocess.PIPE, universal_newlines=True) def __call__(self, mangled): self.proc.stdin.write(mangled + '\n') self.proc.stdin.flush() return self.proc.stdout.readline().rstrip() def close(self): self.proc.stdin.close() self.proc.stdout.close() self.proc.wait() def check_version(max_versions, version, arch) -> bool: if '_' in version: (lib, _, ver) = version.rpartition('_') else: lib = version ver = '0' ver = tuple([int(x) for x in ver.split('.')]) if not lib in max_versions: return False if isinstance(max_versions[lib], tuple): return ver <= max_versions[lib] else: return ver <= max_versions[lib][arch] def check_imported_symbols(filename) -> bool: elf = pixie.load(filename) cppfilt = CPPFilt() ok: bool = True for symbol in elf.dyn_symbols: if not symbol.is_import: continue sym = symbol.name.decode() version = symbol.version.decode() if symbol.version is not None else None if version and not check_version(MAX_VERSIONS, version, elf.hdr.e_machine): print('{}: symbol {} from unsupported version {}'.format(filename, cppfilt(sym), version)) ok = False return ok def check_exported_symbols(filename) -> bool: elf = pixie.load(filename) cppfilt = CPPFilt() ok: bool = True for symbol in elf.dyn_symbols: if not symbol.is_export: continue sym = symbol.name.decode() if elf.hdr.e_machine == pixie.EM_RISCV or sym in IGNORE_EXPORTS: continue print('{}: export of symbol {} not allowed'.format(filename, cppfilt(sym))) ok = False return ok def check_ELF_libraries(filename) -> bool: ok: bool = True elf = pixie.load(filename) for library_name in elf.query_dyn_tags(pixie.DT_NEEDED): assert(isinstance(library_name, bytes)) if library_name.decode() not in ELF_ALLOWED_LIBRARIES: print('{}: NEEDED library {} is not allowed'.format(filename, library_name.decode())) ok = False return ok def check_MACHO_libraries(filename) -> bool: ok: bool = True binary = lief.parse(filename) for dylib in binary.libraries: split = dylib.name.split('/') if split[-1] not in MACHO_ALLOWED_LIBRARIES: print(f'{split[-1]} is not in ALLOWED_LIBRARIES!') ok = False return ok def check_MACHO_min_os(filename) -> bool: binary = lief.parse(filename) if binary.build_version.minos == [10,14,0]: return True return False def check_MACHO_sdk(filename) -> bool: binary = lief.parse(filename) if binary.build_version.sdk == [10, 15, 6]: return True return False def check_PE_libraries(filename) -> bool: ok: bool = True binary = lief.parse(filename) for dylib in binary.libraries: if dylib not in PE_ALLOWED_LIBRARIES: print(f'{dylib} is not in ALLOWED_LIBRARIES!') ok = False return ok def check_PE_subsystem_version(filename) -> bool: binary = lief.parse(filename) major: int = binary.optional_header.major_subsystem_version minor: int = binary.optional_header.minor_subsystem_version if major == 6 and minor == 1: return True return False CHECKS = { 'ELF': [ ('IMPORTED_SYMBOLS', check_imported_symbols), ('EXPORTED_SYMBOLS', check_exported_symbols), ('LIBRARY_DEPENDENCIES', check_ELF_libraries) ], 'MACHO': [ ('DYNAMIC_LIBRARIES', check_MACHO_libraries), ('MIN_OS', check_MACHO_min_os), ('SDK', check_MACHO_sdk), ], 'PE' : [ ('DYNAMIC_LIBRARIES', check_PE_libraries), ('SUBSYSTEM_VERSION', check_PE_subsystem_version), ] } def identify_executable(executable) -> Optional[str]: with open(filename, 'rb') as f: magic = f.read(4) if magic.startswith(b'MZ'): return 'PE' elif magic.startswith(b'\x7fELF'): return 'ELF' elif magic.startswith(b'\xcf\xfa'): return 'MACHO' return None if __name__ == '__main__': retval: int = 0 for filename in sys.argv[1:]: try: etype = identify_executable(filename) if etype is None: print(f'{filename}: unknown format') retval = 1 continue failed: List[str] = [] for (name, func) in CHECKS[etype]: if not func(filename): failed.append(name) if failed: print(f'{filename}: failed {" ".join(failed)}') retval = 1 except IOError: print(f'{filename}: cannot open') retval = 1 sys.exit(retval)