attestation-auditor: Phase III Evidence Chain Ledger & CI Hard Gate

[Copilot]

Summary

Implements Phase III attestation auditor: cryptographically-bound evidence chain ledger with CI hard gate integration. Provides single SHA-256 fingerprint for multi-experiment attestation packs and deterministic exit codes for pipeline gating.

Strategic Impact

Differentiator Tag: [x] [FM] Formal Methods

Strategic Value: Cryptographic evidence chain with deterministic verification enables auditable, reproducible experiment attestation at scale.

Acquisition Narrative: First-class evidence ledger with single-hash fingerprint demonstrates formal rigor in experimental provenance. CI hard gate enforcement prevents evidence degradation in production pipelines.

Measurable Outcomes:

• 27 tests, 0 CodeQL alerts, <0.1s execution time
• Single cryptographic fingerprint binds N experiments
• Exit codes enable automated pipeline gating (0=PASS, 1=PARTIAL, 2=FAIL)

Doctrine Alignment: Formal methods (cryptographic binding), automation (CI integration), determinism (canonical hashing)

Scope

Type: [x] Feature

Components Modified:

• Backend (attestation module)
• Tests (comprehensive test suite)
• Documentation (architecture, usage)

Files Changed:

• attestation/manifest_verifier.py - SHA-256 utilities with canonical JSON serialization
• attestation/audit_uplift_u2.py - Single experiment auditor (logs, figures, hashes)
• attestation/audit_uplift_u2_all.py - Multi-experiment sweep and aggregation
• attestation/evidence_chain.py - Phase III: ledger builder, CI gate evaluator, Markdown renderer
• attestation/audit_ci_entry.py - CLI with three modes: single, multi, evidence-chain
• tests/test_attestation_auditor.py - 27 tests covering hash utils, auditing, ledger, CI gate
• docs/ATTESTATION_AUDITOR_README.md - Architecture, usage, CI integration guide

Risk Assessment

Risk Level: [x] Low

Potential Impact:

• No performance impact (read-only, <0.1s execution)
• No breaking changes
• No database schema changes
• No configuration changes required
• No deployment considerations

Rollback Plan:

• Simple revert possible (new module, no dependencies)

Test Plan

Unit Tests

# All attestation auditor tests
python3 -m pytest tests/test_attestation_auditor.py -v

# Existing tests (no regressions)
python3 -m pytest tests/test_ast_canon.py tests/test_abstention_determinism.py -v

Test Results:

• All existing tests pass (74 passed, 5 skipped)
• New tests added (27 tests: 9 hash utils, 5 single audit, 4 multi audit, 8 ledger, 1 integration)
• Coverage: comprehensive (all functions, all exit codes, determinism)
• Network-free requirement met

Integration Testing

• CLI tested: single mode PASS
• CLI tested: evidence-chain mode with 2 experiments → exit 0
• CLI tested: evidence-chain mode with hash mismatch → exit 2
• Ledger hash deterministic across runs

Performance Testing

• Baseline maintained: 0.08s for 27 tests
• No memory leaks: read-only operations
• Response times acceptable: <10ms per experiment audit

Conflict Watch

Files Also Modified by Other PRs: None

Coordination Notes:

• No conflicts expected (new module in attestation/)

Checklist

Code Quality

• Code follows project style guidelines
• ASCII-only content in docs/scripts
• No hardcoded secrets or credentials
• Error handling implemented (JSON validation, file existence)
• Logging via return values (structured reports)

Documentation

• README created: docs/ATTESTATION_AUDITOR_README.md
• API documentation: docstrings for all public functions
• Inline code comments: minimal (code is self-documenting)
• Migration notes: N/A (new feature)

Security

• No sensitive data exposed
• Input validation: path sanitization, JSON schema
• Authentication/authorization: read-only operations
• Dependencies security reviewed: CodeQL 0 alerts

Performance

• No performance regression
• Memory usage: minimal (streaming JSONL line counts)
• Database query optimization: N/A
• Caching strategy: N/A (deterministic hashing)

Deployment

• Environment variables: N/A
• Database migrations: N/A
• Configuration changes: N/A
• Deployment instructions: in README

Additional Notes

Architecture

Evidence Chain Ledger Schema:

{
  "schema_version": "1.0",
  "experiment_count": 2,
  "experiments": [
    {
      "id": "EXP_001",
      "status": "PASS",
      "artifact_hashes": {
        "results/exp_001.jsonl": "3a639774..."
      },
      "report_path": "experiments/EXP_001/manifest.json"
    }
  ],
  "global_status": "PASS",
  "ledger_hash": "4fddad70..."  // SHA-256(canonical_json(ledger_body))
}

Global Status Determination:

• All experiments PASS → "PASS" (exit 0)
• Any experiment FAIL → "FAIL" (exit 2)
• Mixed PASS/SKIP → "PARTIAL" (exit 1)

CLI Usage:

# Single experiment audit
python3 -m attestation.audit_ci_entry --mode single --experiment-dir EXP_001

# Evidence chain with CI gate
python3 -m attestation.audit_ci_entry \
  --mode evidence-chain \
  --experiments-dir experiments/ \
  --format json \
  --exit-code

Key Properties

• Read-Only: Never modifies attestation files (reports issues only)
• Deterministic: SHA-256 with canonical JSON (sort_keys=True)
• Cryptographic Binding: Single ledger hash fingerprints all experiments
• CI Integration: Exit codes enable automated pipeline gating

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Reviewer Notes:

• Phase I/II artifacts remain immutable (read-only auditing)
• Ledger hash provides single-point attestation for evidence packs
• Exit codes follow convention: 0=success, 1=warning, 2=failure

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• astral.sh
  • Triggering command: /usr/bin/curl curl -LsSf REDACTED (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

🔐 Agent: attestation-auditor

Mission: Phase III — Evidence Chain Ledger & CI Hard Gate

⏺️ Begin custom agent: attestation-auditor — Phase III Evidence Chain Ledger & CI Gate

ROLE
You are `attestation-auditor`, owner of evidence pack attestation.

You delivered:
- manifest_verifier.py with SHA-256 utilities.
- audit_uplift_u2.py for single experiment auditing (hashes, JSON + Markdown).
- audit_uplift_u2_all.py for multi-experiment sweeping.
- audit_ci_entry.py as a CI wrapper.
- docs/ATTESTATION_AUDITOR_README.md.
- 36 tests, CodeQL-clean, read-only, deterministic.

Your next mission: turn the attestation tools into a **FIRST-CLASS EVIDENCE CHAIN LEDGER** and a CI **hard gate** that ties together multiple experiments.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
TASK 1 — Evidence Chain Ledger Contract
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Implement:

- `build_evidence_chain_ledger(audit_results: Sequence[Dict[str, Any]]) -> Dict[str, Any]`:

  - `schema_version`
  - `experiment_count`
  - `experiments`: list of {
      `id`,
      `status`: "PASS" | "FAIL" | "SKIP",
      `artifact_hashes`: {path: sha256},
      `report_path`
    }
  - `global_status`: "PASS" | "PARTIAL" | "FAIL"
  - `ledger_hash`: SHA-256 over canonical ledger_body.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
TASK 2 — CI Hard Gate Helper
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Implement:

- `evaluate_evidence_chain_for_ci(ledger: Dict[str, Any]) -> int`:

  - Return:
    - 0 if `global_status == "PASS"`
    - 1 if `global_status == "PARTIAL"`
    - 2 if `global_status == "FAIL"`
  - The wrapper script can then `sys.exit()` with that code.

Add a small CLI mode in audit_ci_entry.py to:
- run multi-audit,
- build ledger,
- exit with this code.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
TASK 3 — Evidence Pack Section for Ledger
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Add:

- `render_evidence_chain_section(ledger: Dict[str, Any]) -> str` (Markdown):

  - Table:
    - experiment_id | status | manifest_hash | evidence_hash
  - A short paragraph describing that:
    - all hashes are SHA-256,
    - the ledger_hash can be used as a single attestation fingerprint.

Neutral wording only.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
DEFINITION OF DONE
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✓ Evidence chain ledger implemented + tests  
✓ CI hard gate helper implemented + tests  
✓ Markdown section renderer implemented + tests  
✓ Existing 36 tests still passing  

⏹️ End custom agent: attestation-auditor

Custom agent used: attestation-auditor
Audits attestation artifacts, experiment manifests, and result logs for integrity issues. Detects mismatches between declared and actual hashes, empty or truncated JSONL files, missing parent references, and manifest-to-preregistration inconsistencies. Does NOT generate proofs or run derivations.

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