Bind installed releases to signed artifact receipts

tools/assessments/installer-receipt.py

@@ -0,0 +1,170 @@
+#!/usr/bin/env python3
+"""Collect live installed payloads and issue an independently signed receipt."""
+
+from __future__ import annotations
+
+import argparse
+import json
+from pathlib import Path
+import sys
+
+
+META_ROOT = Path(__file__).resolve().parents[2]
+for tools_root in (META_ROOT / "tools" / "assessments", META_ROOT / "tools" / "release"):
+    if str(tools_root) not in sys.path:
+        sys.path.insert(0, str(tools_root))
+
+from cryptography.hazmat.primitives import serialization  # noqa: E402
+from cryptography.hazmat.primitives.asymmetric.ed25519 import (  # noqa: E402
+    Ed25519PrivateKey,
+)
+
+from govoplan_assessment import collect_installed_composition  # noqa: E402
+from govoplan_assessment.atomic_io import (  # noqa: E402
+    AtomicJsonWriteError,
+    atomic_write_json,
+)
+from govoplan_assessment.capability_fit import (  # noqa: E402
+    canonical_hash,
+    review_capability_fit,
+)
+from govoplan_assessment.evidence import validate_payload  # noqa: E402
+from govoplan_assessment.installer_receipt import (  # noqa: E402
+    issue_installer_receipt,
+)
+
+
+MAX_INPUT_BYTES = 16 * 1024 * 1024
+MAX_OUTPUT_BYTES = 4 * 1024 * 1024
+
+
+def main(argv: list[str] | None = None) -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--assessment", type=Path, required=True)
+    parser.add_argument("--assessment-schema", type=Path, default=META_ROOT / "docs" / "capability-fit.schema.json")
+    parser.add_argument("--catalog", type=Path, required=True)
+    parser.add_argument("--keyring", type=Path, required=True)
+    parser.add_argument("--trusted-keyring", type=Path, required=True)
+    parser.add_argument("--receipt-id", required=True)
+    parser.add_argument("--signing-key", required=True, metavar="KEY_ID=/PATH/PRIVATE.pem")
+    parser.add_argument(
+        "--python-artifact",
+        action="append",
+        default=[],
+        required=True,
+        metavar="PACKAGE=/PATH/TO/CONSUMED.whl",
+        help="Exact wheel consumed by this installer; repeat for every package.",
+    )
+    parser.add_argument("--evidence-output", type=Path, required=True)
+    parser.add_argument("--receipt-output", type=Path, required=True)
+    parser.add_argument("--installed-evidence-schema", type=Path, default=META_ROOT / "docs" / "installed-composition-evidence.schema.json")
+    parser.add_argument("--receipt-schema", type=Path, default=META_ROOT / "docs" / "installer-receipt.schema.json")
+    args = parser.parse_args(argv)
+    if args.evidence_output.resolve() == args.receipt_output.resolve():
+        parser.error("evidence and receipt output paths must differ")
+
+    assessment = read_object(args.assessment, label="assessment")
+    assessment_schema = read_object(args.assessment_schema, label="assessment schema")
+    catalog = read_object(args.catalog, label="catalog")
+    keyring = read_object(args.keyring, label="published keyring")
+    trusted_keyring = read_object(args.trusted_keyring, label="trusted keyring")
+    evidence_schema = read_object(args.installed_evidence_schema, label="installed evidence schema")
+    receipt_schema = read_object(args.receipt_schema, label="installer receipt schema")
+    release = catalog.get("release")
+    if not isinstance(release, dict) or release.get("keyring_sha256") != canonical_hash(keyring):
+        parser.error("catalog does not pin the supplied published keyring")
+
+    evidence = collect_installed_composition(assessment=assessment)
+    if validate_payload(payload=evidence, schema=evidence_schema):
+        parser.error("live installed observation does not satisfy its bounded schema")
+    report = review_capability_fit(
+        assessment=assessment,
+        schema=assessment_schema,
+        catalog=catalog,
+        published_keyring=keyring,
+        trusted_keyring=trusted_keyring,
+        workspace_root=None,
+        installed_evidence=evidence,
+        installed_evidence_schema=evidence_schema,
+        installed_evidence_mode="direct_local",
+    )
+    required_scopes = (
+        "catalog_signature_and_keyring",
+        "catalog_signature_and_trusted_keyring",
+        "published_keyring_hash",
+        "release_metadata",
+        "installed_artifacts",
+        "installed_record_integrity",
+    )
+    if any(report["proof_scope"].get(scope, {}).get("valid") is not True for scope in required_scopes):
+        parser.error("trusted catalog and live installed-composition checks must pass before receipt issuance")
+
+    key_id, private_key = read_signing_key(args.signing_key)
+    consumed_artifacts = parse_package_paths(tuple(args.python_artifact))
+    receipt = issue_installer_receipt(
+        assessment=assessment,
+        catalog=catalog,
+        installed_evidence=evidence,
+        receipt_id=args.receipt_id,
+        key_id=key_id,
+        private_key=private_key,
+        consumed_artifacts=consumed_artifacts,
+        same_process_observation=True,
+    )
+    if validate_payload(payload=receipt, schema=receipt_schema):
+        parser.error("issued installer receipt does not satisfy its bounded schema")
+    write_object(args.evidence_output, evidence, label="installed evidence")
+    write_object(args.receipt_output, receipt, label="installer receipt")
+    print(json.dumps({"receipt_id": args.receipt_id, "evidence_output": str(args.evidence_output), "receipt_output": str(args.receipt_output)}, sort_keys=True))
+    return 0
+
+
+def read_object(path: Path, *, label: str) -> dict[str, object]:
+    try:
+        if path.stat().st_size > MAX_INPUT_BYTES:
+            raise ValueError("input exceeds size limit")
+        encoded = path.read_bytes()
+        payload = json.loads(encoded.decode("utf-8"))
+    except (OSError, UnicodeDecodeError, json.JSONDecodeError, ValueError) as exc:
+        raise SystemExit(f"Could not read {label}") from exc
+    if not isinstance(payload, dict):
+        raise SystemExit(f"{label.capitalize()} must be a JSON object")
+    return payload
+
+
+def read_signing_key(value: str) -> tuple[str, Ed25519PrivateKey]:
+    key_id, separator, path_text = value.partition("=")
+    if not separator or not key_id or not path_text:
+        raise SystemExit("--signing-key must use KEY_ID=/path/to/private.pem")
+    try:
+        key = serialization.load_pem_private_key(Path(path_text).expanduser().read_bytes(), password=None)
+    except (OSError, ValueError) as exc:
+        raise SystemExit("Could not read installer signing key") from exc
+    if not isinstance(key, Ed25519PrivateKey):
+        raise SystemExit("Installer signing key must be Ed25519")
+    return key_id, key
+
+
+def parse_package_paths(values: tuple[str, ...]) -> dict[str, Path]:
+    result: dict[str, Path] = {}
+    for value in values:
+        package, separator, path_text = value.partition("=")
+        package = package.strip()
+        path_text = path_text.strip()
+        if not separator or not package or not path_text or package in result:
+            raise SystemExit(
+                "--python-artifact must uniquely use PACKAGE=/path/to/consumed.whl"
+            )
+        result[package] = Path(path_text).expanduser()
+    return result
+
+
+def write_object(path: Path, payload: dict[str, object], *, label: str) -> None:
+    try:
+        atomic_write_json(path, payload, max_bytes=MAX_OUTPUT_BYTES)
+    except AtomicJsonWriteError as exc:
+        raise SystemExit(f"Could not securely write {label}") from exc
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())