mirror of
https://github.com/lief-project/LIEF
synced 2026-06-08 15:30:44 +00:00
lief-agent
76 lines
2.0 KiB
Python
76 lines
2.0 KiB
Python
#!/usr/bin/env python
|
|
"""Change the program interpreter of an ELF executable.
|
|
|
|
Replaces the ``PT_INTERP`` entry (the ``.interp`` section) of a
|
|
dynamically-linked ELF executable with the path of another ELF
|
|
interpreter, then writes the patched binary to disk with the execute
|
|
bit set.
|
|
|
|
Example:
|
|
|
|
$ python elf_change_interpreter.py \\
|
|
--output /tmp/ls_musl /bin/ls /usr/lib/ld-musl-x86_64.so.1
|
|
"""
|
|
|
|
import argparse
|
|
import stat
|
|
import sys
|
|
from pathlib import Path
|
|
|
|
import lief
|
|
|
|
|
|
def change_interpreter(
|
|
target: Path, interpreter: Path, output: Path | None = None
|
|
) -> int:
|
|
if not target.is_file() or not lief.is_elf(target):
|
|
print(f"Wrong target! ({target})", file=sys.stderr)
|
|
return 1
|
|
|
|
if not interpreter.is_file() or not lief.is_elf(interpreter):
|
|
print(f"Wrong interpreter! ({interpreter})", file=sys.stderr)
|
|
return 1
|
|
|
|
binary = lief.ELF.parse(target)
|
|
if binary is None:
|
|
print(f"Failed to parse '{target}' as ELF", file=sys.stderr)
|
|
return 1
|
|
|
|
if not binary.has_interpreter:
|
|
print("The given target doesn't have an interpreter!", file=sys.stderr)
|
|
return 1
|
|
|
|
binary.interpreter = str(interpreter)
|
|
|
|
output_path = output or Path(f"{target.name}_updated")
|
|
|
|
output_path.unlink(missing_ok=True)
|
|
|
|
binary.write(output_path)
|
|
|
|
# Restore the execute bit that LIEF doesn't propagate.
|
|
st = output_path.stat()
|
|
output_path.chmod(st.st_mode | stat.S_IEXEC)
|
|
return 0
|
|
|
|
|
|
def main() -> int:
|
|
parser = argparse.ArgumentParser(description=__doc__.splitlines()[0])
|
|
parser.add_argument(
|
|
"-o", "--output", help="Path to the rewritten binary", default=None, type=Path
|
|
)
|
|
parser.add_argument("target", metavar="<elf>", help="Target ELF file", type=Path)
|
|
parser.add_argument(
|
|
"interpreter",
|
|
metavar="<interpreter>",
|
|
help="Path to the new interpreter",
|
|
type=Path,
|
|
)
|
|
|
|
args = parser.parse_args()
|
|
return change_interpreter(args.target, args.interpreter, args.output)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
sys.exit(main())
|