Pairing Store Hardening:
- Increased pairing code length from 8 to 16 chars (80-bit entropy)
- Added HMAC-SHA256 signatures for store integrity verification
- Added rate limiting (10 attempts/minute per channel)
- Store is automatically reset if signature verification fails
- New ApproveChannelPairingCodeResult type includes rateLimited case
Exec Approval Nonces (Replay Protection):
- Added one-time-use nonces for approval socket requests
- Nonces are generated with 32 bytes of entropy (base64url encoded)
- Nonces expire after 5 minutes with automatic cleanup
- Responses must include matching nonce to be accepted
- Exported functions for testing: generateApprovalNonce, verifyAndConsumeNonce, isNonceValid
Tests:
- 11 pairing store tests (6 new security tests)
- 38 exec-approvals tests (8 new nonce tests)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
