#!/usr/bin/env python3
"""Check a Linux module's versioned imports against its target Module.symvers.

Requires kmod's modprobe. A pass checks symbol CRCs only, not complete ABI,
vermagic, CFI, signatures, firmware or hardware behaviour.
"""
import argparse
from pathlib import Path
import subprocess
import sys


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("symvers", type=Path)
    parser.add_argument("modules", nargs="+", type=Path)
    args = parser.parse_args()
    exports = {}
    for line in args.symvers.read_text().splitlines():
        fields = line.split()
        if len(fields) >= 2:
            exports[fields[1]] = int(fields[0], 16)
    if not exports:
        parser.error("Module.symvers contains no exports")
    failed = False
    for module in args.modules:
        result = subprocess.run(
            ["modprobe", "--show-modversions", str(module.resolve())],
            text=True, capture_output=True,
        )
        if result.returncode or not result.stdout.strip():
            print(f"UNVERIFIED {module}: {result.stderr.strip() or 'no versioned imports'}")
            failed = True
            continue
        mismatch = 0
        imports = result.stdout.splitlines()
        for line in imports:
            crc, symbol = line.split()
            expected = exports.get(symbol)
            if expected != int(crc, 16):
                mismatch += 1
                target = "missing export" if expected is None else f"0x{expected:08x}"
                print(f"  {symbol}: module={crc}, kernel={target}")
        failed |= bool(mismatch)
        print(f"{'FAIL' if mismatch else 'PASS'} {module}: "
              f"{mismatch}/{len(imports)} incompatible versioned imports")
    return int(failed)


if __name__ == "__main__":
    sys.exit(main())