# Runbook: Authentication Failures

## Alert

**RdevAPIAuthFailures**: High rate of authentication failures

## Impact

- Legitimate users unable to access API
- Potential security incident (brute force)
- Service degradation

## Investigation

### 1. Confirm the Issue

```bash
# Check auth failure metrics
curl -s http://rdev-api:8080/metrics | grep auth_failures

# Check auth logs
kubectl -n rdev logs -l app=rdev-api --since=10m | grep -E "(UNAUTHORIZED|KEY_REVOKED|KEY_EXPIRED|IP_NOT_ALLOWED)"
```

### 2. Identify Failure Type

```bash
# Count by failure reason
kubectl -n rdev logs -l app=rdev-api --since=10m | \
  grep -oE '"code":"[^"]+' | sort | uniq -c | sort -rn
```

Common reasons:
- `UNAUTHORIZED` - Invalid or missing key
- `KEY_REVOKED` - Key was revoked
- `KEY_EXPIRED` - Key has expired
- `IP_NOT_ALLOWED` - IP not in allowlist

### 3. Check for Attack Patterns

```bash
# Check unique IPs making failed requests
kubectl -n rdev logs -l app=rdev-api --since=10m | \
  grep UNAUTHORIZED | grep -oE '"client_ip":"[^"]+' | sort | uniq -c | sort -rn

# Check request patterns
kubectl -n rdev logs -l app=rdev-api --since=10m | \
  grep UNAUTHORIZED | grep -oE '"path":"[^"]+' | sort | uniq -c | sort -rn
```

## Remediation

### If Keys Are Invalid (UNAUTHORIZED)

1. Verify keys exist in database:
   ```bash
   kubectl -n rdev exec -it deployment/rdev-api -- sh
   psql $DATABASE_URL -c "SELECT id, name, key_prefix, revoked_at FROM api_keys;"
   ```

2. Help users create new keys if needed

3. If brute force detected:
   - Block offending IPs at ingress level
   - Increase rate limiting

### If Keys Are Revoked (KEY_REVOKED)

1. Check who revoked and when:
   ```sql
   SELECT id, name, revoked_at, revoked_by FROM api_keys WHERE revoked_at IS NOT NULL;
   ```

2. Determine if revocation was intentional

3. Issue new keys to affected users if legitimate

### If Keys Are Expired (KEY_EXPIRED)

1. Check which keys expired:
   ```sql
   SELECT id, name, expires_at FROM api_keys WHERE expires_at < NOW();
   ```

2. Issue new keys to affected users

3. Consider extending default expiration if too short

### If IP Not Allowed (IP_NOT_ALLOWED)

1. Check which keys have IP restrictions:
   ```sql
   SELECT id, name, allowed_ips FROM api_keys WHERE allowed_ips IS NOT NULL;
   ```

2. Verify client IPs match allowlist

3. Update allowlist if legitimate IPs changed:
   - Cloud provider IP ranges change
   - User moved networks

### If Under Attack

1. **Immediate**: Block at ingress
   ```yaml
   # Add to ingress annotations
   nginx.ingress.kubernetes.io/whitelist-source-range: "10.0.0.0/8,192.168.0.0/16"
   ```

2. **Short-term**: Increase rate limits
   ```bash
   kubectl -n rdev set env deployment/rdev-api RATE_LIMIT_RPS=2
   ```

3. **Long-term**:
   - Implement IP-based blocking
   - Add fail2ban-style lockout
   - Review API key issuance process

## Verification

```bash
# Check auth success rate
curl -s http://rdev-api:8080/metrics | grep -E "auth_(requests|failures)"

# Test authentication
curl -H "X-API-Key: $VALID_KEY" http://rdev-api:8080/projects

# Check logs for successful auths
kubectl -n rdev logs -l app=rdev-api --since=5m | grep "request completed" | head -5
```

## Post-Incident

1. Review auth failure patterns
2. Update IP allowlists if needed
3. Communicate with affected users
4. Consider additional security measures:
   - API key rotation policy
   - Automated key expiration alerts
   - IP-based anomaly detection
