335 lines
12 KiB
Python
335 lines
12 KiB
Python
#!/usr/bin/env python3
|
|
|
|
import argparse
|
|
import os
|
|
import pprint
|
|
import subprocess
|
|
import sys
|
|
from collections import defaultdict
|
|
from contextlib import contextmanager
|
|
from dataclasses import dataclass
|
|
from itertools import chain
|
|
from pathlib import Path, PurePath
|
|
from typing import DefaultDict, Iterator, List, Optional, Set, Tuple
|
|
|
|
from elftools.common.exceptions import ELFError # type: ignore
|
|
from elftools.elf.dynamic import DynamicSection # type: ignore
|
|
from elftools.elf.elffile import ELFFile # type: ignore
|
|
from elftools.elf.enums import ENUM_E_TYPE, ENUM_EI_OSABI # type: ignore
|
|
|
|
|
|
@contextmanager
|
|
def open_elf(path: Path) -> Iterator[ELFFile]:
|
|
with path.open('rb') as stream:
|
|
yield ELFFile(stream)
|
|
|
|
|
|
def is_static_executable(elf: ELFFile) -> bool:
|
|
# Statically linked executables have an ELF type of EXEC but no INTERP.
|
|
return (elf.header["e_type"] == 'ET_EXEC'
|
|
and not elf.get_section_by_name(".interp"))
|
|
|
|
|
|
def is_dynamic_executable(elf: ELFFile) -> bool:
|
|
# We do not require an ELF type of EXEC. This also catches
|
|
# position-independent executables, as they typically have an INTERP
|
|
# section but their ELF type is DYN.
|
|
return bool(elf.get_section_by_name(".interp"))
|
|
|
|
|
|
def get_dependencies(elf: ELFFile) -> List[str]:
|
|
dependencies = []
|
|
# This convoluted code is here on purpose. For some reason, using
|
|
# elf.get_section_by_name(".dynamic") does not always return an
|
|
# instance of DynamicSection, but that is required to call iter_tags
|
|
for section in elf.iter_sections():
|
|
if isinstance(section, DynamicSection):
|
|
for tag in section.iter_tags('DT_NEEDED'):
|
|
dependencies.append(tag.needed)
|
|
break # There is only one dynamic section
|
|
|
|
return dependencies
|
|
|
|
|
|
def get_rpath(elf: ELFFile) -> List[str]:
|
|
# This convoluted code is here on purpose. For some reason, using
|
|
# elf.get_section_by_name(".dynamic") does not always return an
|
|
# instance of DynamicSection, but that is required to call iter_tags
|
|
for section in elf.iter_sections():
|
|
if isinstance(section, DynamicSection):
|
|
for tag in section.iter_tags('DT_RUNPATH'):
|
|
return tag.runpath.split(':')
|
|
|
|
for tag in section.iter_tags('DT_RPATH'):
|
|
return tag.rpath.split(':')
|
|
|
|
break # There is only one dynamic section
|
|
|
|
return []
|
|
|
|
|
|
def get_arch(elf: ELFFile) -> str:
|
|
return elf.get_machine_arch()
|
|
|
|
|
|
def get_osabi(elf: ELFFile) -> str:
|
|
return elf.header["e_ident"]["EI_OSABI"]
|
|
|
|
|
|
def osabi_are_compatible(wanted: str, got: str) -> bool:
|
|
"""
|
|
Tests whether two OS ABIs are compatible, taking into account the
|
|
generally accepted compatibility of SVR4 ABI with other ABIs.
|
|
"""
|
|
if not wanted or not got:
|
|
# One of the types couldn't be detected, so as a fallback we'll
|
|
# assume they're compatible.
|
|
return True
|
|
|
|
# Generally speaking, the base ABI (0x00), which is represented by
|
|
# readelf(1) as "UNIX - System V", indicates broad compatibility
|
|
# with other ABIs.
|
|
#
|
|
# TODO: This isn't always true. For example, some OSes embed ABI
|
|
# compatibility into SHT_NOTE sections like .note.tag and
|
|
# .note.ABI-tag. It would be prudent to add these to the detection
|
|
# logic to produce better ABI information.
|
|
if wanted == 'ELFOSABI_SYSV':
|
|
return True
|
|
|
|
# Similarly here, we should be able to link against a superset of
|
|
# features, so even if the target has another ABI, this should be
|
|
# fine.
|
|
if got == 'ELFOSABI_SYSV':
|
|
return True
|
|
|
|
# Otherwise, we simply return whether the ABIs are identical.
|
|
return wanted == got
|
|
|
|
|
|
def glob(path: Path, pattern: str, recursive: bool) -> Iterator[Path]:
|
|
return path.rglob(pattern) if recursive else path.glob(pattern)
|
|
|
|
|
|
cached_paths: Set[Path] = set()
|
|
soname_cache: DefaultDict[Tuple[str, str], List[Tuple[Path, str]]] = defaultdict(list)
|
|
|
|
|
|
def populate_cache(initial: List[Path], recursive: bool =False) -> None:
|
|
lib_dirs = list(initial)
|
|
|
|
while lib_dirs:
|
|
lib_dir = lib_dirs.pop(0)
|
|
|
|
if lib_dir in cached_paths:
|
|
continue
|
|
|
|
cached_paths.add(lib_dir)
|
|
|
|
for path in glob(lib_dir, "*.so*", recursive):
|
|
if not path.is_file():
|
|
continue
|
|
|
|
resolved = path.resolve()
|
|
try:
|
|
with open_elf(path) as elf:
|
|
osabi = get_osabi(elf)
|
|
arch = get_arch(elf)
|
|
rpath = [Path(p) for p in get_rpath(elf)
|
|
if p and '$ORIGIN' not in p]
|
|
lib_dirs += rpath
|
|
soname_cache[(path.name, arch)].append((resolved.parent, osabi))
|
|
|
|
except ELFError:
|
|
# Not an ELF file in the right format
|
|
pass
|
|
|
|
|
|
def find_dependency(soname: str, soarch: str, soabi: str) -> Optional[Path]:
|
|
for lib, libabi in soname_cache[(soname, soarch)]:
|
|
if osabi_are_compatible(soabi, libabi):
|
|
return lib
|
|
return None
|
|
|
|
|
|
@dataclass
|
|
class Dependency:
|
|
file: Path # The file that contains the dependency
|
|
name: Path # The name of the dependency
|
|
found: bool = False # Whether it was found somewhere
|
|
|
|
|
|
def auto_patchelf_file(path: Path, runtime_deps: list[Path]) -> list[Dependency]:
|
|
try:
|
|
with open_elf(path) as elf:
|
|
|
|
if is_static_executable(elf):
|
|
# No point patching these
|
|
print(f"skipping {path} because it is statically linked")
|
|
return []
|
|
|
|
if elf.num_segments() == 0:
|
|
# no segment (e.g. object file)
|
|
print(f"skipping {path} because it contains no segment")
|
|
return []
|
|
|
|
file_arch = get_arch(elf)
|
|
if interpreter_arch != file_arch:
|
|
# Our target architecture is different than this file's
|
|
# architecture, so skip it.
|
|
print(f"skipping {path} because its architecture ({file_arch})"
|
|
f" differs from target ({interpreter_arch})")
|
|
return []
|
|
|
|
file_osabi = get_osabi(elf)
|
|
if not osabi_are_compatible(interpreter_osabi, file_osabi):
|
|
print(f"skipping {path} because its OS ABI ({file_osabi}) is"
|
|
f" not compatible with target ({interpreter_osabi})")
|
|
return []
|
|
|
|
file_is_dynamic_executable = is_dynamic_executable(elf)
|
|
|
|
file_dependencies = map(Path, get_dependencies(elf))
|
|
|
|
except ELFError:
|
|
return []
|
|
|
|
rpath = []
|
|
if file_is_dynamic_executable:
|
|
print("setting interpreter of", path)
|
|
subprocess.run(
|
|
["patchelf", "--set-interpreter", interpreter_path.as_posix(), path.as_posix()],
|
|
check=True)
|
|
rpath += runtime_deps
|
|
|
|
print("searching for dependencies of", path)
|
|
dependencies = []
|
|
# Be sure to get the output of all missing dependencies instead of
|
|
# failing at the first one, because it's more useful when working
|
|
# on a new package where you don't yet know the dependencies.
|
|
for dep in file_dependencies:
|
|
if dep.is_absolute() and dep.is_file():
|
|
# This is an absolute path. If it exists, just use it.
|
|
# Otherwise, we probably want this to produce an error when
|
|
# checked (because just updating the rpath won't satisfy
|
|
# it).
|
|
continue
|
|
elif (libc_lib / dep).is_file():
|
|
# This library exists in libc, and will be correctly
|
|
# resolved by the linker.
|
|
continue
|
|
|
|
if found_dependency := find_dependency(dep.name, file_arch, file_osabi):
|
|
rpath.append(found_dependency)
|
|
dependencies.append(Dependency(path, dep, True))
|
|
print(f" {dep} -> found: {found_dependency}")
|
|
else:
|
|
dependencies.append(Dependency(path, dep, False))
|
|
print(f" {dep} -> not found!")
|
|
|
|
# Dedup the rpath
|
|
rpath_str = ":".join(dict.fromkeys(map(Path.as_posix, rpath)))
|
|
|
|
if rpath:
|
|
print("setting RPATH to:", rpath_str)
|
|
subprocess.run(
|
|
["patchelf", "--set-rpath", rpath_str, path.as_posix()],
|
|
check=True)
|
|
|
|
return dependencies
|
|
|
|
|
|
def auto_patchelf(
|
|
paths_to_patch: List[Path],
|
|
lib_dirs: List[Path],
|
|
runtime_deps: List[Path],
|
|
recursive: bool =True,
|
|
ignore_missing: List[str] = []) -> None:
|
|
|
|
if not paths_to_patch:
|
|
sys.exit("No paths to patch, stopping.")
|
|
|
|
# Add all shared objects of the current output path to the cache,
|
|
# before lib_dirs, so that they are chosen first in find_dependency.
|
|
populate_cache(paths_to_patch, recursive)
|
|
populate_cache(lib_dirs)
|
|
|
|
dependencies = []
|
|
for path in chain.from_iterable(glob(p, '*', recursive) for p in paths_to_patch):
|
|
if not path.is_symlink() and path.is_file():
|
|
dependencies += auto_patchelf_file(path, runtime_deps)
|
|
|
|
missing = [dep for dep in dependencies if not dep.found]
|
|
|
|
# Print a summary of the missing dependencies at the end
|
|
print(f"auto-patchelf: {len(missing)} dependencies could not be satisfied")
|
|
failure = False
|
|
for dep in missing:
|
|
if dep.name.name in ignore_missing or "*" in ignore_missing:
|
|
print(f"warn: auto-patchelf ignoring missing {dep.name} wanted by {dep.file}")
|
|
else:
|
|
print(f"error: auto-patchelf could not satisfy dependency {dep.name} wanted by {dep.file}")
|
|
failure = True
|
|
|
|
if failure:
|
|
sys.exit('auto-patchelf failed to find all the required dependencies.\n'
|
|
'Add the missing dependencies to --libs or use '
|
|
'`--ignore-missing="foo.so.1 bar.so etc.so"`.')
|
|
|
|
|
|
def main() -> None:
|
|
parser = argparse.ArgumentParser(
|
|
prog="auto-patchelf",
|
|
description='auto-patchelf tries as hard as possible to patch the'
|
|
' provided binary files by looking for compatible'
|
|
'libraries in the provided paths.')
|
|
parser.add_argument(
|
|
"--ignore-missing",
|
|
nargs="*",
|
|
type=str,
|
|
help="Do not fail when some dependencies are not found.")
|
|
parser.add_argument(
|
|
"--no-recurse",
|
|
dest="recursive",
|
|
action="store_false",
|
|
help="Patch only the provided paths, and ignore their children")
|
|
parser.add_argument(
|
|
"--paths", nargs="*", type=Path,
|
|
help="Paths whose content needs to be patched.")
|
|
parser.add_argument(
|
|
"--libs", nargs="*", type=Path,
|
|
help="Paths where libraries are searched for.")
|
|
parser.add_argument(
|
|
"--runtime-dependencies", nargs="*", type=Path,
|
|
help="Paths to prepend to the runtime path of executable binaries.")
|
|
|
|
print("automatically fixing dependencies for ELF files")
|
|
args = parser.parse_args()
|
|
pprint.pprint(vars(args))
|
|
|
|
auto_patchelf(
|
|
args.paths,
|
|
args.libs,
|
|
args.runtime_dependencies,
|
|
args.recursive,
|
|
args.ignore_missing)
|
|
|
|
|
|
interpreter_path: Path = None # type: ignore
|
|
interpreter_osabi: str = None # type: ignore
|
|
interpreter_arch: str = None # type: ignore
|
|
libc_lib: Path = None # type: ignore
|
|
|
|
if __name__ == "__main__":
|
|
nix_support = Path(os.environ['NIX_BINTOOLS']) / 'nix-support'
|
|
interpreter_path = Path((nix_support / 'dynamic-linker').read_text().strip())
|
|
libc_lib = Path((nix_support / 'orig-libc').read_text().strip()) / 'lib'
|
|
|
|
with open_elf(interpreter_path) as interpreter:
|
|
interpreter_osabi = get_osabi(interpreter)
|
|
interpreter_arch = get_arch(interpreter)
|
|
|
|
if interpreter_arch and interpreter_osabi and interpreter_path and libc_lib:
|
|
main()
|
|
else:
|
|
sys.exit("Failed to parse dynamic linker (ld) properties.")
|