Trace Policy Provenance

Read the Sandbox Annotations

openshell sandbox get <sandbox>

Note the values of apf.nvidia.com/correlation-id, apf.nvidia.com/document-digest, apf.nvidia.com/policy-version, apf.nvidia.com/bundle-id, apf.nvidia.com/signer-identity, and apf.nvidia.com/provenance-token.

Verify the Provenance Token

The token is a compact JWT signed with EdDSA by the policy service’s document signing key. The key is published at /.well-known/jwks.json on the policy service’s HTTP surface, under the token’s kid. This script verifies the signature and prints the claims. It uses the Python cryptography package.

import base64, json, sys, urllib.request
from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PublicKey
def b64u(value):
    return base64.urlsafe_b64decode(value + "=" * (-len(value) % 4))
token, jwks_url = sys.argv[1], sys.argv[2]
header_b64, payload_b64, signature_b64 = token.split(".")
kid = json.loads(b64u(header_b64))["kid"]
jwks = json.load(urllib.request.urlopen(jwks_url))
key = next(k for k in jwks["keys"] if k["kid"] == kid)
Ed25519PublicKey.from_public_bytes(b64u(key["x"])).verify(
    b64u(signature_b64), f"{header_b64}.{payload_b64}".encode()
)
print(json.dumps(json.loads(b64u(payload_b64)), indent=2))

python3 verify_provenance.py "$TOKEN" http://127.0.0.1:19200/.well-known/jwks.json

The script raises InvalidSignature if the token was altered. On success, check that the claims match the annotations:

Before OpenShell admits the sandbox, the interceptor verifies the token’s signature and expiry, checks the jti and apf/document-digest claims against the annotations, and recomputes the sandbox policy spec digest. It does not compare sub, apf/version, or apf/bundle-id, so those checks are yours. apf/bundle-id names the bundle the policy service loaded at startup, even after a later refresh.

Find the Admission Records

The token’s jti is the correlation ID of the admission:

jq -c --arg id "$JTI" 'select(.correlation_id == $id)' \
  "$APF_AUDIT_LOG_DIR/apf-policy-gateway-interceptor-audit.jsonl"

The policy_injection record lists the spec paths APF patched, and the admission_validation record’s reason code shows whether the spec digest check ran.

Find the Bundle Verification

Search the policy service’s audit file for the bundle and revision named in the token:

jq -c --arg id "$BUNDLE_ID" --argjson rev "$VERSION" \
  'select(.event_type == "policy_verification" and .bundle_id == $id and .policy_revision == $rev)' \
  "$APF_AUDIT_LOG_DIR/apf-policy-service-audit.jsonl"

A record with "outcome":"success" shows the policy service verified that revision. Its bundle_digest is the SHA-256 of the signed bundle file. If the policy service loaded a bundle with a different id after it started, the token still carries the startup id, so filter on the revision alone.

Verify the Signed Bundle

Hash the signed bundle file from your artifact store and compare it with the record’s bundle_digest. Then verify its signature against the trust roots:

sha256sum team-bundle/team-bundle.yaml
tail -n 4 team-bundle/team-bundle.yaml
./target/release/apf-compile compile \
  --bundle-path team-bundle/team-bundle.yaml \
  --trust-root-dir trust-roots \
  --verify-only

The signature document’s keyid names the trust root, and so the signing authority, that authorized the bundle.