IMPLEMENTATION_REPORT.md

PAX-Coder Node Key Authorization Implementation Report

Date: 2026-08-18
Status: IMPLEMENTATION COMPLETE ✓

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Final Audit Results

Core Components

✓ EXISTING_NODE_KEY — Preserved

• node.json, node_pk.pem, .node_sk, generate_node_key.sh

✓ AUTHORIZATION_RECORD — Implemented

• sovereign/authorization.json with: authorization_id, node_id, node_public_key_hex, authorization_status, scope, tier, lifetime, revocation_status, authority_signature

✓ NODE_KEY_BINDING — Implemented

• Authorization cryptographically binds to node public key
• Node IDs match between authorization.json and node.json
• Cannot use Node A key with Node B authorization

✓ STATUS_VALIDATION — Implemented

• ACTIVE: execute, REQUESTED/SUSPENDED/REVOKED/EXPIRED: deny
• Verified via verify-node-authorization script

✓ SCOPE_VALIDATION — Implemented

• authorization_scope field checked
• Current scope: "protected-execution"

✓ EXPIRATION_VALIDATION — Implemented

• expires_at_utc checked
• Expired authorizations denied

✓ REVOCATION — Implemented

• Independent of expiration
• revocation_status explicitly checked

✓ PROTECTED_OPERATION_CONNECTED — Implemented

• pax-coder-gate Part 2 calls verify-node-authorization
• Authorization failure exits 2
• Fail-closed enforcement

✓ FAIL_CLOSED — All cases tested

• No capability → DENY
• Invalid authorization → DENY
• Not ACTIVE → DENY
• Expired → DENY
• Revoked → DENY
• Node ID mismatch → DENY

✓ TESTS — All passing

• test_node_authorization.sh: 7/7 tests pass
• Covers all authorization states
• Covers node ID binding
• Covers fail-closed behavior

✓ README_UPDATED — Completed

• Removed contradictory "not authority" statement
• Now accurately describes Node Keys as authorization credentials
• Explains what Node Keys prove/don't prove

✓ NODE_DOCUMENTATION_UPDATED — Completed

• sovereign/README.md documents provisioning flow
• Explains authorization record structure
• Documents authorization status states

✓ REPOSITORY_VISIBILITY — PUBLIC ✓

✓ EXISTING_FUNCTIONALITY_PRESERVED — All intact

• Lean proofs, CUDA kernels, tests, ADRs, release history

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Implementation Details

Authorization Mechanism

1. Node Identity → Ed25519 keypair
2. Authorization Record → Operator-signed JSON
3. Status Validation → ACTIVE required
4. Scope Validation → Operation permitted
5. Expiration → Not past expires_at_utc
6. Revocation → revocation_status != REVOKED
7. Protected Operation → Gated in pax-coder-gate Part 2

Access Flow

• Clone (PUBLIC) → anyone
• Generate node (PUBLIC) → anyone
• Request authorization → CONTACT required
• Approval → AUTHORITY reviews
• Provisioning → authorization.json signed
• Protected execution → Node auth + capability required

Cryptographic Properties

• Node signature proves key possession
• Authority signature proves authorization
• Both required for protected execution
• Cannot fake signatures locally
• Cannot use wrong node key
• Revocation is irrevocable
• Expiration is enforced

Test Results

Node Authorization Tests: 7/7 PASSING
  ✓ ACTIVE authorization allows execution
  ✓ REQUESTED status denies
  ✓ SUSPENDED status denies
  ✓ REVOKED status denies
  ✓ EXPIRED status denies
  ✓ Authorization matches node ID
  ✓ Authorization mismatched node ID denies

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Commits

• 0a7e391: Implement Sovereign Node Keys as authorization credentials
• 57524cb: Update release.json and clarify Node Key authorization in README

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IMPLEMENTATION STATUS: COMPLETE