Feat/tinfoil conformance

[lsd-cat]

Follows the other SDKs to implement conformance testing. Build the dedicated CLI and add a CI job.

---

Summary by cubic

Adds a cross-SDK tinfoil-conformance CLI and CI workflow to exercise policy-layer verification across Sigstore, TDX, and SEV-SNP, plus EHBP key binding. The TDX public‑API path now runs the real verifier end‑to‑end with config re‑baseline and accepted‑QV‑results gating.

• New Features

  • tinfoil-conformance CLI: capabilities, verify-sigstore, verify-measurement, verify-hardware-measurements, verify-attestation-tdx, verify-attestation-sev (adapter/public API), verify-full (standard/bundle/pinned; JSON-in/JSON-out), and verify-ehbp-key-binding.
  • Sigstore: verify_sigstore_bundle_with_policy with SigstorePolicy/SigstoreVerification; hermetic trust-root via sigstore.TrustedRoot; emits bundle observables; capability flags align with sigstore behavior.
  • TDX: structural quote checks; header/body parsing with TD attribute decode; full §4.7 TCB evaluation with injected collateral and verification-time override; §4.8 extended-TD pins; Intel root injection; accepts non-terminal TCB; execution_mode="public_api" now drives the real verifier end‑to‑end with re‑baselined config and §4.7.7 accepted‑QV‑results enforcement.
  • SEV-SNP: v3 report verification with injected VCEK and embedded/injected ASK/ARK; §3.4 cross-checks; rejects MIGRATE_MA; execution_mode="public_api" uses attestation.verify_sev_attestation_v2 (no network) and applies §3.7 policy pins; time override is system-clock-only.
  • verify-full: chains Sigstore → SEV, compares measurements (SPEC §11), supports pinned/bundle flows, and returns a final fingerprint with originating-stage rejections.
  • EHBP key binding: extracts HPKE key from report_data[32:64] and validates via the SDK’s EHBP parser; rejects with EHBP_KEY_BINDING_MISMATCH.
  • Capabilities updated: add stages verify-measurement, verify-hardware-measurements, verify-full, verify-ehbp-key-binding; flow_modes_supported=["standard","bundle","pinned"]; TDX/SEV support and extended checks; verification_time_override="supported" (TDX) / "system-clock-only" (SEV); measurement.compare_multiplatform_to_tdx_supported=true; transport_ehbp_supported=true; ehbp.key_binding_supported=true.

• Refactors

  • Expanded TDX/SEV error classifiers to SPEC-coded rejections, including policy/collateral messages; strict prefix matching for workflow_ref_prefix (SPEC §5.3).
  • Added inner helpers for Sigstore/SEV used by verify-full; isolated Python-specific Sigstore hooks under tinfoil.conformance.sigstore.
  • CI workflow runs the cross-SDK suite against the tinfoil-conformance binary.

^{Written for commit 33b1785. Summary will update on new commits.}

[cubic-dev-ai]

10 issues found across 5 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/tinfoil/conformance/cli.py">

<violation number="1" location="src/tinfoil/conformance/cli.py:944">
P1: Custom agent: **Check System Design and Architectural Patterns**

Runtime monkey-patching of library module globals from CLI code creates tight coupling and bypasses explicit interfaces. The conformance CLI directly mutates `collateral_tdx.datetime`, `cert_utils.datetime`, `fetch_collateral`, and `intel_root_ca.INTEL_SGX_ROOT_CA_PEM` rather than using dependency injection or parameterized library calls. This breaks proper layering and makes internal library refactors hazardous.</violation>

<violation number="2" location="src/tinfoil/conformance/cli.py:1008">
P1: CRLs are accepted in `_evaluate_collateral` without signature verification, enabling revocation-check bypass with injected collateral.</violation>

<violation number="3" location="src/tinfoil/conformance/cli.py:1261">
P2: Invalid `min_tee_tcb_svn_hex` is silently ignored, effectively disabling the minimum TCB policy check.</violation>

<violation number="4" location="src/tinfoil/conformance/cli.py:1568">
P2: Mandatory VCEK TCB extension checks are bypassed when extensions are missing or malformed due to `continue` paths.</violation>

<violation number="5" location="src/tinfoil/conformance/cli.py:1689">
P1: Custom agent: **Flag Security Vulnerabilities**

Unbounded gzip decompression of untrusted attestation input enables memory/CPU DoS via a crafted gzip bomb.</violation>
</file>

<sub>Tip: instead of fixing issues one by one fix them all with cubic

Re-trigger cubic</sub>

[cubic-dev-ai]

P1: Custom agent: Flag Security Vulnerabilities

Unbounded gzip decompression of untrusted attestation input enables memory/CPU DoS via a crafted gzip bomb.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 1689:

<comment>Unbounded gzip decompression of untrusted attestation input enables memory/CPU DoS via a crafted gzip bomb.</comment>

<file context>
@@ -0,0 +1,2029 @@
+        return ("REPORT_FORMAT_UNSUPPORTED", "3.1",
+                f"attestation_doc_b64 not valid base64: {e}")
+    try:
+        report_bytes = _gzip.decompress(gz_bytes)
+    except Exception as e:
+        return ("REPORT_FORMAT_UNSUPPORTED", "3.1",
</file context>

[cubic-dev-ai]

P1: CRLs are accepted in _evaluate_collateral without signature verification, enabling revocation-check bypass with injected collateral.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 1008:

<comment>CRLs are accepted in `_evaluate_collateral` without signature verification, enabling revocation-check bypass with injected collateral.</comment>

<file context>
@@ -0,0 +1,2029 @@
+        root_crl_obj = None
+        if pck_crl_der:
+            crl = x509.load_der_x509_crl(pck_crl_der)
+            pck_crl_obj = PckCrl(crl=crl, ca_type="platform",
+                                 next_update=crl.next_update_utc or datetime.now(timezone.utc))
+        if root_crl_der:
</file context>

[cubic-dev-ai]

P1: Custom agent: Check System Design and Architectural Patterns

Runtime monkey-patching of library module globals from CLI code creates tight coupling and bypasses explicit interfaces. The conformance CLI directly mutates collateral_tdx.datetime, cert_utils.datetime, fetch_collateral, and intel_root_ca.INTEL_SGX_ROOT_CA_PEM rather than using dependency injection or parameterized library calls. This breaks proper layering and makes internal library refactors hazardous.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 944:

<comment>Runtime monkey-patching of library module globals from CLI code creates tight coupling and bypasses explicit interfaces. The conformance CLI directly mutates `collateral_tdx.datetime`, `cert_utils.datetime`, `fetch_collateral`, and `intel_root_ca.INTEL_SGX_ROOT_CA_PEM` rather than using dependency injection or parameterized library calls. This breaks proper layering and makes internal library refactors hazardous.</comment>

<file context>
@@ -0,0 +1,2029 @@
+    from ..attestation import cert_utils as _cert_mod
+    orig_coll_dt = _coll_mod.datetime
+    orig_cert_dt = _cert_mod.datetime
+    _coll_mod.datetime = _FixedDatetime
+    _cert_mod.datetime = _FixedDatetime
+    try:
</file context>

[cubic-dev-ai]

P2: Mandatory VCEK TCB extension checks are bypassed when extensions are missing or malformed due to continue paths.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 1568:

<comment>Mandatory VCEK TCB extension checks are bypassed when extensions are missing or malformed due to `continue` paths.</comment>

<file context>
@@ -0,0 +1,2029 @@
+    ]
+    for name, oid, report_val in tcb_pairs:
+        raw = ext_map.get(oid)
+        if raw is None:
+            continue
+        cert_val = _decode_int_ext_value(raw)
</file context>

[cubic-dev-ai]

P2: Invalid min_tee_tcb_svn_hex is silently ignored, effectively disabling the minimum TCB policy check.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 1261:

<comment>Invalid `min_tee_tcb_svn_hex` is silently ignored, effectively disabling the minimum TCB policy check.</comment>

<file context>
@@ -0,0 +1,2029 @@
+                                f"tee_tcb_svn[{i}]={tee_tcb_svn[i]} < min[{i}]={minimum[i]} "
+                                f"(quote={tee_tcb_svn.hex()}, minimum={minimum.hex()})")
+        except ValueError:
+            pass
+
+    return "", ""
</file context>

[cubic-dev-ai]

2 issues found across 1 file (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/tinfoil/conformance/cli.py">

<violation number="1" location="src/tinfoil/conformance/cli.py:2034">
P2: Missing top-level JSON object validation can crash the CLI on non-object input.</violation>

<violation number="2" location="src/tinfoil/conformance/cli.py:2040">
P2: Hex parsing error handling is incomplete; non-string report_data_hex bypasses the current exception handler.</violation>
</file>

<sub>Tip: Review your code locally with the cubic CLI to iterate faster.

Fix all with cubic | Re-trigger cubic</sub>

[cubic-dev-ai]

P2: Hex parsing error handling is incomplete; non-string report_data_hex bypasses the current exception handler.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 2040:

<comment>Hex parsing error handling is incomplete; non-string report_data_hex bypasses the current exception handler.</comment>

<file context>
@@ -2003,6 +2010,88 @@ def cmd_verify_full() -> int:
+
+    try:
+        report_data = bytes.fromhex(inp.get("report_data_hex", ""))
+    except ValueError as e:
+        sys.stderr.write(f"report_data_hex not valid hex: {e}\n")
+        return EXIT_BAD_INPUT
</file context>

Suggested change

	except ValueError as e:
	except (TypeError, ValueError) as e:

[cubic-dev-ai]

P2: Missing top-level JSON object validation can crash the CLI on non-object input.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 2034:

<comment>Missing top-level JSON object validation can crash the CLI on non-object input.</comment>

<file context>
@@ -2003,6 +2010,88 @@ def cmd_verify_full() -> int:
+    except json.JSONDecodeError as e:
+        sys.stderr.write(f"input is not valid JSON: {e}\n")
+        return EXIT_BAD_INPUT
+    if inp.get("schema_version") != "1":
+        sys.stderr.write('input.schema_version != "1"\n')
+        return EXIT_BAD_INPUT
</file context>

[cubic-dev-ai]

1 issue found across 1 file (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/tinfoil/conformance/cli.py">

<violation number="1" location="src/tinfoil/conformance/cli.py:1340">
P2: Custom agent: **Nuke belt-and-suspenders**

Broad `except Exception: pass` swallows re-parsing errors for data already validated upstream, constituting unnecessary belt-and-suspenders defensive coding.</violation>
</file>

<sub>Tip: Review your code locally with the cubic CLI to iterate faster.

Fix all with cubic | Re-trigger cubic</sub>

[cubic-dev-ai]

P2: Custom agent: Nuke belt-and-suspenders

Broad except Exception: pass swallows re-parsing errors for data already validated upstream, constituting unnecessary belt-and-suspenders defensive coding.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tinfoil/conformance/cli.py, line 1340:

<comment>Broad `except Exception: pass` swallows re-parsing errors for data already validated upstream, constituting unnecessary belt-and-suspenders defensive coding.</comment>

<file context>
@@ -1291,6 +1327,24 @@ def _cmd_verify_attestation_tdx_public(inp: dict[str, Any], policy: dict[str, An
+    # synthetic vectors at the baseline gate before the fixture's targeted
+    # check. Re-baseline to the quote's own values; the fixture's SPEC §4.8
+    # pins are then enforced precisely by _enforce_extended_policy below.
+    try:
+        _tb = parse_tdx_quote(base64.b64decode(inp["quote_b64"])).td_quote_body
+        config_kwargs.setdefault("expected_td_attributes", _tb.td_attributes)
</file context>

Suggested change

	try:
	_tb = parse_tdx_quote(base64.b64decode(inp["quote_b64"])).td_quote_body
	config_kwargs.setdefault("expected_td_attributes", _tb.td_attributes)
	config_kwargs.setdefault("expected_xfam", _tb.xfam)
	config_kwargs.setdefault("expected_minimum_tee_tcb_svn", _tb.tee_tcb_svn)
	config_kwargs.setdefault("accepted_mr_seams", (_tb.mr_seam,))
	except Exception:
	pass
	_tb = parse_tdx_quote(base64.b64decode(inp["quote_b64"])).td_quote_body
	config_kwargs.setdefault("expected_td_attributes", _tb.td_attributes)
	config_kwargs.setdefault("expected_xfam", _tb.xfam)
	config_kwargs.setdefault("expected_minimum_tee_tcb_svn", _tb.tee_tcb_svn)
	config_kwargs.setdefault("accepted_mr_seams", (_tb.mr_seam,))