# Calejo Control Adapter - Compliance & Certification Guide

## Overview

This guide provides comprehensive documentation for regulatory compliance and certification processes for the Calejo Control Adapter, focusing on industrial automation security standards and critical infrastructure protection.

## Regulatory Framework

### Applicable Standards

| Standard | Scope | Certification Body |
|----------|-------|-------------------|
| **IEC 62443** | Industrial Automation and Control Systems Security | IECEE CB Scheme |
| **ISO 27001** | Information Security Management Systems | ISO Certification Bodies |
| **NIS2 Directive** | Network and Information Systems Security | EU Member State Authorities |
| **IEC 61511** | Functional Safety - Safety Instrumented Systems | IEC Certification Bodies |

### Compliance Mapping

#### IEC 62443 Compliance

**Security Levels**:
- **SL 1**: Protection against casual or coincidental violation
- **SL 2**: Protection against intentional violation using simple means
- **SL 3**: Protection against intentional violation using sophisticated means
- **SL 4**: Protection against intentional violation using sophisticated means with extended resources

**Target Security Level**: **SL 3** for municipal wastewater infrastructure

#### ISO 27001 Compliance

**Information Security Management System (ISMS)**:
- Risk assessment and treatment
- Security policies and procedures
- Access control and authentication
- Incident management and response
- Business continuity planning

#### NIS2 Directive Compliance

**Essential Requirements**:
- Risk management measures
- Incident handling procedures
- Business continuity planning
- Supply chain security
- Vulnerability management

## Security Controls Implementation

### Access Control (IEC 62443-3-3 SR 1.1)

#### Authentication Mechanisms

```python
# Authentication implementation
class AuthenticationManager:
    def authenticate_user(self, username: str, password: str) -> AuthenticationResult:
        """Authenticate user with multi-factor verification"""
        # Password verification
        if not self.verify_password(username, password):
            self.audit_log.log_failed_login(username, "INVALID_PASSWORD")
            return AuthenticationResult(success=False, reason="Invalid credentials")
        
        # Multi-factor authentication
        if not self.verify_mfa(username):
            self.audit_log.log_failed_login(username, "MFA_FAILED")
            return AuthenticationResult(success=False, reason="MFA verification failed")
        
        # Generate JWT token
        token = self.generate_jwt_token(username)
        self.audit_log.log_successful_login(username)
        
        return AuthenticationResult(success=True, token=token)
```

#### Role-Based Access Control

```python
# RBAC implementation
class AuthorizationManager:
    ROLES_PERMISSIONS = {
        'operator': [
            'read_pump_status',
            'set_setpoint',
            'activate_emergency_stop',
            'clear_emergency_stop'
        ],
        'supervisor': [
            'read_pump_status',
            'set_setpoint',
            'activate_emergency_stop',
            'clear_emergency_stop',
            'view_audit_logs',
            'manage_users'
        ],
        'administrator': [
            'read_pump_status',
            'set_setpoint',
            'activate_emergency_stop',
            'clear_emergency_stop',
            'view_audit_logs',
            'manage_users',
            'system_configuration',
            'security_management'
        ]
    }
    
    def has_permission(self, role: str, permission: str) -> bool:
        """Check if role has specific permission"""
        return permission in self.ROLES_PERMISSIONS.get(role, [])
```

### Use Control (IEC 62443-3-3 SR 1.2)

#### Session Management

```python
# Session control implementation
class SessionManager:
    def __init__(self):
        self.active_sessions = {}
        self.max_session_duration = 3600  # 1 hour
        self.max_inactivity = 900  # 15 minutes
    
    def create_session(self, user_id: str, token: str) -> Session:
        """Create new user session with security controls"""
        session = Session(
            user_id=user_id,
            token=token,
            created_at=datetime.utcnow(),
            last_activity=datetime.utcnow(),
            expires_at=datetime.utcnow() + timedelta(seconds=self.max_session_duration)
        )
        
        self.active_sessions[token] = session
        return session
    
    def validate_session(self, token: str) -> ValidationResult:
        """Validate session with security checks"""
        session = self.active_sessions.get(token)
        
        if not session:
            return ValidationResult(valid=False, reason="Session not found")
        
        # Check session expiration
        if datetime.utcnow() > session.expires_at:
            del self.active_sessions[token]
            return ValidationResult(valid=False, reason="Session expired")
        
        # Check inactivity timeout
        inactivity = datetime.utcnow() - session.last_activity
        if inactivity.total_seconds() > self.max_inactivity:
            del self.active_sessions[token]
            return ValidationResult(valid=False, reason="Session inactive")
        
        # Update last activity
        session.last_activity = datetime.utcnow()
        
        return ValidationResult(valid=True, session=session)
```

### System Integrity (IEC 62443-3-3 SR 1.3)

#### Software Integrity Verification

```python
# Integrity verification implementation
class IntegrityManager:
    def verify_application_integrity(self) -> IntegrityResult:
        """Verify application integrity using checksums and signatures"""
        integrity_checks = []
        
        # Verify core application files
        core_files = [
            'src/main.py',
            'src/core/safety.py',
            'src/security/authentication.py',
            'src/protocols/opcua_server.py'
        ]
        
        for file_path in core_files:
            checksum = self.calculate_checksum(file_path)
            expected_checksum = self.get_expected_checksum(file_path)
            
            if checksum != expected_checksum:
                integrity_checks.append(IntegrityCheck(
                    file=file_path,
                    status='FAILED',
                    reason='Checksum mismatch'
                ))
            else:
                integrity_checks.append(IntegrityCheck(
                    file=file_path,
                    status='PASSED'
                ))
        
        # Verify digital signatures
        signature_valid = self.verify_digital_signatures()
        
        return IntegrityResult(
            checks=integrity_checks,
            overall_status='PASSED' if all(c.status == 'PASSED' for c in integrity_checks) and signature_valid else 'FAILED'
        )
```

## Audit and Accountability

### Comprehensive Audit Logging

#### Audit Event Structure

```python
# Audit logging implementation
class ComplianceAuditLogger:
    def log_security_event(self, event: SecurityEvent):
        """Log security event with compliance metadata"""
        audit_record = ComplianceAuditRecord(
            timestamp=datetime.utcnow(),
            event_type=event.event_type,
            severity=event.severity,
            user_id=event.user_id,
            station_id=event.station_id,
            pump_id=event.pump_id,
            ip_address=event.ip_address,
            protocol=event.protocol,
            action=event.action,
            resource=event.resource,
            result=event.result,
            reason=event.reason,
            compliance_standard=['IEC_62443', 'ISO_27001', 'NIS2'],
            event_data=event.data,
            app_name='Calejo Control Adapter',
            app_version='2.0.0',
            environment=self.environment
        )
        
        # Store in compliance database
        self.database.store_audit_record(audit_record)
        
        # Generate real-time alert for critical events
        if event.severity in ['HIGH', 'CRITICAL']:
            self.alert_system.send_alert(audit_record)
```

#### Required Audit Events

| Event Type | Severity | Compliance Standard | Retention |
|------------|----------|---------------------|-----------|
| **USER_LOGIN** | MEDIUM | IEC 62443, ISO 27001 | 1 year |
| **USER_LOGOUT** | LOW | IEC 62443, ISO 27001 | 1 year |
| **SETPOINT_CHANGED** | HIGH | IEC 62443, NIS2 | 7 years |
| **EMERGENCY_STOP_ACTIVATED** | CRITICAL | IEC 62443, NIS2 | 10 years |
| **SAFETY_VIOLATION** | HIGH | IEC 62443, IEC 61511 | 7 years |
| **CONFIGURATION_CHANGED** | MEDIUM | IEC 62443, ISO 27001 | 3 years |

## Risk Assessment and Management

### Security Risk Assessment

#### Risk Assessment Methodology

```python
# Risk assessment implementation
class SecurityRiskAssessor:
    def assess_system_risks(self) -> RiskAssessment:
        """Comprehensive security risk assessment"""
        risks = []
        
        # Assess authentication risks
        auth_risk = self.assess_authentication_risk()
        risks.append(auth_risk)
        
        # Assess network communication risks
        network_risk = self.assess_network_risk()
        risks.append(network_risk)
        
        # Assess data integrity risks
        integrity_risk = self.assess_integrity_risk()
        risks.append(integrity_risk)
        
        # Calculate overall risk score
        overall_score = self.calculate_overall_risk(risks)
        
        return RiskAssessment(
            risks=risks,
            overall_score=overall_score,
            assessment_date=datetime.utcnow(),
            assessor='Automated Risk Assessment System'
        )
    
    def assess_authentication_risk(self) -> Risk:
        """Assess authentication-related risks"""
        controls = [
            RiskControl('Multi-factor authentication', 'IMPLEMENTED', 0.8),
            RiskControl('Strong password policy', 'IMPLEMENTED', 0.7),
            RiskControl('Session timeout', 'IMPLEMENTED', 0.6),
            RiskControl('Account lockout', 'IMPLEMENTED', 0.7)
        ]
        
        return Risk(
            category='AUTHENTICATION',
            description='Unauthorized access to control systems',
            likelihood=0.3,
            impact=0.9,
            controls=controls,
            residual_risk=self.calculate_residual_risk(0.3, 0.9, controls)
        )
```

### Risk Treatment Plan

#### Risk Mitigation Strategies

| Risk Category | Mitigation Strategy | Control Implementation | Target Date |
|---------------|---------------------|------------------------|-------------|
| **Unauthorized Access** | Multi-factor authentication, RBAC | AuthenticationManager, AuthorizationManager | Completed |
| **Data Tampering** | Digital signatures, checksums | IntegrityManager | Completed |
| **Network Attacks** | TLS encryption, firewalls | Protocol security layers | Completed |
| **System Failure** | Redundancy, monitoring | Health monitoring, alerts | Completed |

## Certification Process

### IEC 62443 Certification

#### Certification Steps

1. **Gap Analysis**
   - Compare current implementation against IEC 62443 requirements
   - Identify compliance gaps and remediation actions
   - Develop certification roadmap

2. **Security Development Lifecycle**
   - Implement secure development practices
   - Conduct security code reviews
   - Perform vulnerability assessments

3. **Security Testing**
   - Penetration testing
   - Vulnerability scanning
   - Security controls testing

4. **Documentation Preparation**
   - Security policies and procedures
   - Risk assessment reports
   - Security architecture documentation

5. **Certification Audit**
   - On-site assessment by certification body
   - Evidence review and validation
   - Compliance verification

#### Required Documentation

- **Security Policy Document**
- **Risk Assessment Report**
- **Security Architecture Description**
- **Security Test Reports**
- **Incident Response Plan**
- **Business Continuity Plan**

### ISO 27001 Certification

#### ISMS Implementation

```python
# ISMS implementation tracking
class ISMSManager:
    def track_compliance_status(self) -> ComplianceStatus:
        """Track ISO 27001 compliance status"""
        controls_status = {}
        
        # Check A.9 Access Control
        controls_status['A.9.1.1'] = self.check_access_control_policy()
        controls_status['A.9.2.1'] = self.check_user_registration()
        controls_status['A.9.2.3'] = self.check_privilege_management()
        
        # Check A.12 Operations Security
        controls_status['A.12.4.1'] = self.check_event_logging()
        controls_status['A.12.4.2'] = self.check_log_protection()
        controls_status['A.12.4.3'] = self.check_clock_synchronization()
        
        # Calculate overall compliance
        total_controls = len(controls_status)
        compliant_controls = sum(1 for status in controls_status.values() if status == 'COMPLIANT')
        compliance_percentage = (compliant_controls / total_controls) * 100
        
        return ComplianceStatus(
            controls=controls_status,
            overall_compliance=compliance_percentage,
            last_assessment=datetime.utcnow()
        )
```

## Evidence Collection

### Compliance Evidence Requirements

#### Technical Evidence

```python
# Evidence collection implementation
class ComplianceEvidenceCollector:
    def collect_technical_evidence(self) -> TechnicalEvidence:
        """Collect technical evidence for compliance audits"""
        evidence = TechnicalEvidence()
        
        # Security configuration evidence
        evidence.security_config = self.get_security_configuration()
        
        # Access control evidence
        evidence.access_logs = self.get_access_logs()
        evidence.user_roles = self.get_user_role_mappings()
        
        # System integrity evidence
        evidence.integrity_checks = self.get_integrity_check_results()
        evidence.patch_levels = self.get_patch_information()
        
        # Network security evidence
        evidence.firewall_rules = self.get_firewall_configuration()
        evidence.tls_certificates = self.get_certificate_info()
        
        return evidence
    
    def generate_compliance_report(self) -> ComplianceReport:
        """Generate comprehensive compliance report"""
        technical_evidence = self.collect_technical_evidence()
        procedural_evidence = self.collect_procedural_evidence()
        
        return ComplianceReport(
            technical_evidence=technical_evidence,
            procedural_evidence=procedural_evidence,
            assessment_date=datetime.utcnow(),
            compliance_status=self.assess_compliance_status(),
            recommendations=self.generate_recommendations()
        )
```

#### Procedural Evidence

- **Security Policies and Procedures**
- **Risk Assessment Documentation**
- **Incident Response Plans**
- **Business Continuity Plans**
- **Training Records**
- **Change Management Records**

## Continuous Compliance Monitoring

### Automated Compliance Checking

```python
# Continuous compliance monitoring
class ComplianceMonitor:
    def monitor_compliance_status(self) -> MonitoringResult:
        """Continuous monitoring of compliance status"""
        checks = []
        
        # Security controls monitoring
        checks.append(self.check_authentication_controls())
        checks.append(self.check_access_controls())
        checks.append(self.check_audit_logging())
        checks.append(self.check_system_integrity())
        checks.append(self.check_network_security())
        
        # Calculate compliance score
        passed_checks = sum(1 for check in checks if check.status == 'PASSED')
        compliance_score = (passed_checks / len(checks)) * 100
        
        return MonitoringResult(
            checks=checks,
            compliance_score=compliance_score,
            timestamp=datetime.utcnow(),
            alerts=self.generate_alerts(checks)
        )
    
    def check_authentication_controls(self) -> ComplianceCheck:
        """Check authentication controls compliance"""
        checks_passed = 0
        total_checks = 4
        
        # Check MFA implementation
        if self.is_mfa_enabled():
            checks_passed += 1
        
        # Check password policy
        if self.is_password_policy_enforced():
            checks_passed += 1
        
        # Check session management
        if self.is_session_management_configured():
            checks_passed += 1
        
        # Check account lockout
        if self.is_account_lockout_enabled():
            checks_passed += 1
        
        return ComplianceCheck(
            category='AUTHENTICATION',
            status='PASSED' if checks_passed == total_checks else 'FAILED',
            score=(checks_passed / total_checks) * 100,
            details=f"{checks_passed}/{total_checks} controls compliant"
        )
```

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*This compliance and certification guide provides comprehensive documentation for achieving and maintaining regulatory compliance. Regular audits and continuous monitoring ensure ongoing compliance with industrial automation security standards.*