verify.py

#!/usr/bin/env python3
"""Re-check every record in the corpus with certkit.

This is the script that makes the corpus an artifact rather than a claim. It
imports `certkit` -- which contains no solver, no search, and no code from the
pipeline that produced these certificates -- and re-derives each obligation from
the published spec before replaying the multipliers against it.

A record passes only if, for every safety conjunct, the system

    domain AND guard AND NOT safety[i]

is refuted by the supplied nonnegative multipliers. Since the certificate is not
permitted to supply its own atoms, a certificate proving some easier unrelated
system cannot pass.

    pip install certkit
    python verify.py

Exit codes:

    0  every record verified
    1  at least one record failed
    2  usage error
"""

from __future__ import annotations

import argparse
import json
import sys
from pathlib import Path
from typing import Any


def main(argv: Any = None) -> int:
    ap = argparse.ArgumentParser(description="Verify the CVE proof corpus with certkit.")
    # Default to the file next to this script, not to the caller's working
    # directory -- the documented one-liner is run from the repository root.
    ap.add_argument(
        "--data",
        type=Path,
        default=Path(__file__).resolve().parent / "cve-proof-corpus.jsonl",
    )
    ap.add_argument("--quiet", action="store_true")
    args = ap.parse_args(argv)

    try:
        from certkit import check_certificate
    except ImportError:
        print("error: certkit is required -- pip install certkit", file=sys.stderr)
        return 2

    if not args.data.is_file():
        print(f"error: {args.data} not found; run export.py first", file=sys.stderr)
        return 2

    rows = [json.loads(line) for line in args.data.read_text(encoding="utf-8").splitlines() if line]

    ok_count = 0
    failures: list[str] = []

    for rec in rows:
        report = check_certificate(rec["spec"], rec["certificate"])
        status = "VERIFIED" if report.ok else "FAILED"
        if report.ok:
            ok_count += 1
        else:
            failures.append(rec["id"])

        if not args.quiet:
            n = rec["n_safety_conjuncts"]
            print(f"  {status:9s} {rec['id']:24s} {rec['cve']:16s} {n} obligation(s)")
            if not report.ok:
                for ob in report.obligations:
                    if not ob["ok"]:
                        print(f"            obligation {ob['index']}: {ob['reason']}")

    print()
    print(f"{ok_count} of {len(rows)} records verified by certkit")

    if failures:
        print(f"FAILED: {', '.join(failures)}", file=sys.stderr)
        return 1

    print("Every published certificate re-checks against its published spec.")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())