Zero Trust Mesh Architecture

import hashlib
import json
import time
from typing import Dict, List, Optional, Tuple, Any
from dataclasses import dataclass, asdict
from enum import Enum
import jwt
import logging
from datetime import datetime, timedelta

class TrustLevel(Enum):
    UNTRUSTED = 0
    LOW = 1
    MEDIUM = 2
    HIGH = 3
    VERIFIED = 4

class AccessDecision(Enum):
    ALLOW = "allow"
    DENY = "deny"
    CONDITIONAL = "conditional"
    STEP_UP = "step_up"

class RiskLevel(Enum):
    MINIMAL = 1
    LOW = 2
    MEDIUM = 3
    HIGH = 4
    CRITICAL = 5

@dataclass
class Identity:
    user_id: str
    username: str
    roles: List[str]
    groups: List[str]
    trust_level: TrustLevel
    last_authentication: datetime
    authentication_methods: List[str]
    risk_score: float
    attributes: Dict[str, Any]

@dataclass
class Device:
    device_id: str
    device_type: str
    os_version: str
    is_managed: bool
    compliance_status: str
    trust_level: TrustLevel
    last_seen: datetime
    location: Optional[str]
    risk_factors: List[str]

@dataclass
class Resource:
    resource_id: str
    resource_type: str
    classification: str
    sensitivity_level: str
    required_trust_level: TrustLevel
    access_policies: List[str]
    data_classification: str

@dataclass
class AccessRequest:
    request_id: str
    identity: Identity
    device: Device
    resource: Resource
    requested_action: str
    context: Dict[str, Any]
    timestamp: datetime
    source_ip: str
    user_agent: str

@dataclass
class AccessDecisionResult:
    decision: AccessDecision
    confidence: float
    risk_level: RiskLevel
    conditions: List[str]
    expiration: Optional[datetime]
    audit_trail: List[Dict[str, Any]]
    reasoning: str

class ZeroTrustPolicyEngine:
    def __init__(self, config: Dict[str, Any]):
        self.config = config
        self.policy_rules = []
        self.risk_calculator = RiskCalculator()
        self.trust_evaluator = TrustEvaluator()
        self.context_analyzer = ContextAnalyzer()
        self.audit_logger = AuditLogger()
        
        self._load_policies()
    
    async def evaluate_access_request(self, request: AccessRequest) -> AccessDecisionResult:
        """Main entry point for zero trust access evaluation"""
        try:
            self.audit_logger.log_access_request(request)
            
            # Step 1: Verify identity authentication
            identity_verification = await self.verify_identity(request.identity)
            if not identity_verification.is_valid:
                return AccessDecisionResult(
                    decision=AccessDecision.DENY,
                    confidence=0.95,
                    risk_level=RiskLevel.HIGH,
                    conditions=[],
                    expiration=None,
                    audit_trail=[identity_verification.audit_entry],
                    reasoning="Identity verification failed"
                )
            
            # Step 2: Assess device trust
            device_trust = await self.assess_device_trust(request.device)
            
            # Step 3: Evaluate resource access policies
            policy_evaluation = await self.evaluate_policies(request)
            
            # Step 4: Calculate contextual risk
            context_risk = await self.calculate_contextual_risk(request)
            
            # Step 5: Make composite access decision
            decision = await self.make_access_decision(
                request, identity_verification, device_trust, 
                policy_evaluation, context_risk
            )
            
            # Step 6: Apply additional conditions if needed
            if decision.decision == AccessDecision.CONDITIONAL:
                decision = await self.apply_conditional_access(request, decision)
            
            # Step 7: Log decision and return
            await self.audit_logger.log_access_decision(request, decision)
            
            return decision
            
        except Exception as e:
            logging.error(f"Access evaluation error: {str(e)}")
            # Fail securely - deny access on error
            return AccessDecisionResult(
                decision=AccessDecision.DENY,
                confidence=1.0,
                risk_level=RiskLevel.CRITICAL,
                conditions=[],
                expiration=None,
                audit_trail=[],
                reasoning=f"System error during evaluation: {str(e)}"
            )
    
    async def verify_identity(self, identity: Identity) -> Any:
        """Verify identity credentials and trust level"""
        verification_result = {
            'is_valid': True,
            'trust_score': 0.0,
            'verification_methods': [],
            'audit_entry': {}
        }
        
        # Check authentication recency
        time_since_auth = datetime.now() - identity.last_authentication
        if time_since_auth > timedelta(hours=8):
            verification_result['trust_score'] -= 0.3
            verification_result['verification_methods'].append('stale_authentication')
        
        # Evaluate authentication methods
        strong_auth_methods = ['mfa', 'biometric', 'certificate', 'smart_card']
        strong_methods_used = len([m for m in identity.authentication_methods if m in strong_auth_methods])
        
        if strong_methods_used >= 2:
            verification_result['trust_score'] += 0.4
        elif strong_methods_used == 1:
            verification_result['trust_score'] += 0.2
        else:
            verification_result['trust_score'] -= 0.2
            verification_result['verification_methods'].append('weak_authentication')
        
        # Check risk score
        if identity.risk_score > 0.7:
            verification_result['trust_score'] -= 0.3
            verification_result['verification_methods'].append('high_risk_user')
        
        # Evaluate trust level
        trust_bonus = {
            TrustLevel.VERIFIED: 0.3,
            TrustLevel.HIGH: 0.2,
            TrustLevel.MEDIUM: 0.1,
            TrustLevel.LOW: -0.1,
            TrustLevel.UNTRUSTED: -0.5
        }
        verification_result['trust_score'] += trust_bonus[identity.trust_level]
        
        # Determine if verification is valid
        verification_result['is_valid'] = verification_result['trust_score'] >= 0.0
        
        verification_result['audit_entry'] = {
            'verification_type': 'identity',
            'user_id': identity.user_id,
            'trust_score': verification_result['trust_score'],
            'methods': verification_result['verification_methods'],
            'timestamp': datetime.now().isoformat()
        }
        
        return type('obj', (object,), verification_result)
    
    async def assess_device_trust(self, device: Device) -> float:
        """Assess device trustworthiness"""
        trust_score = 0.5  # Base score
        
        # Managed device bonus
        if device.is_managed:
            trust_score += 0.3
        else:
            trust_score -= 0.2
        
        # Compliance status
        if device.compliance_status == 'compliant':
            trust_score += 0.2
        elif device.compliance_status == 'non_compliant':
            trust_score -= 0.4
        
        # Device trust level
        trust_bonus = {
            TrustLevel.VERIFIED: 0.3,
            TrustLevel.HIGH: 0.2,
            TrustLevel.MEDIUM: 0.0,
            TrustLevel.LOW: -0.2,
            TrustLevel.UNTRUSTED: -0.5
        }
        trust_score += trust_bonus[device.trust_level]
        
        # Risk factors penalty
        risk_penalty = len(device.risk_factors) * 0.1
        trust_score -= risk_penalty
        
        # Device age/staleness
        time_since_seen = datetime.now() - device.last_seen
        if time_since_seen > timedelta(days=30):
            trust_score -= 0.2
        
        return max(0.0, min(1.0, trust_score))
    
    async def evaluate_policies(self, request: AccessRequest) -> Dict[str, Any]:
        """Evaluate access policies for the request"""
        policy_results = {
            'applicable_policies': [],
            'violations': [],
            'requirements': [],
            'overall_result': 'allow'
        }
        
        # Check role-based access control
        user_roles = set(request.identity.roles)
        required_roles = set(self._get_required_roles(request.resource))
        
        if not required_roles.intersection(user_roles):
            policy_results['violations'].append('insufficient_roles')
            policy_results['overall_result'] = 'deny'
        
        # Check resource sensitivity requirements
        if request.resource.sensitivity_level == 'highly_confidential':
            if request.identity.trust_level.value < TrustLevel.HIGH.value:
                policy_results['violations'].append('insufficient_trust_for_sensitive_resource')
                policy_results['requirements'].append('step_up_authentication')
        
        # Check time-based access policies
        current_hour = datetime.now().hour
        if hasattr(request.resource, 'allowed_hours'):
            allowed_hours = getattr(request.resource, 'allowed_hours', range(24))
            if current_hour not in allowed_hours:
                policy_results['violations'].append('outside_allowed_hours')
                policy_results['overall_result'] = 'deny'
        
        # Check location-based policies
        if hasattr(request, 'source_location'):
            if not self._is_location_allowed(request.source_location, request.resource):
                policy_results['violations'].append('unauthorized_location')
                policy_results['overall_result'] = 'deny'
        
        return policy_results
    
    async def calculate_contextual_risk(self, request: AccessRequest) -> RiskLevel:
        """Calculate risk based on request context"""
        risk_factors = []
        risk_score = 0.0
        
        # Unusual time access
        current_hour = datetime.now().hour
        if current_hour < 6 or current_hour > 22:
            risk_factors.append('unusual_time_access')
            risk_score += 0.2
        
        # Geographic risk
        if hasattr(request, 'source_location'):
            if request.source_location != request.device.location:
                risk_factors.append('location_mismatch')
                risk_score += 0.3
        
        # User behavior analysis
        if request.identity.risk_score > 0.6:
            risk_factors.append('high_user_risk')
            risk_score += 0.4
        
        # Device risk factors
        if len(request.device.risk_factors) > 2:
            risk_factors.append('multiple_device_risks')
            risk_score += 0.3
        
        # Resource sensitivity
        if request.resource.sensitivity_level == 'highly_confidential':
            risk_score += 0.2
        
        # Convert score to risk level
        if risk_score >= 0.8:
            return RiskLevel.CRITICAL
        elif risk_score >= 0.6:
            return RiskLevel.HIGH
        elif risk_score >= 0.4:
            return RiskLevel.MEDIUM
        elif risk_score >= 0.2:
            return RiskLevel.LOW
        else:
            return RiskLevel.MINIMAL
    
    async def make_access_decision(self, request: AccessRequest, 
                                 identity_verification: Any, 
                                 device_trust: float,
                                 policy_evaluation: Dict[str, Any], 
                                 context_risk: RiskLevel) -> AccessDecisionResult:
        """Make final access decision based on all factors"""
        
        # Start with policy evaluation result
        if policy_evaluation['overall_result'] == 'deny':
            return AccessDecisionResult(
                decision=AccessDecision.DENY,
                confidence=0.95,
                risk_level=context_risk,
                conditions=[],
                expiration=None,
                audit_trail=[],
                reasoning="Policy violation: " + ", ".join(policy_evaluation['violations'])
            )
        
        # Calculate composite trust score
        identity_trust = identity_verification.trust_score
        composite_trust = (identity_trust + device_trust) / 2
        
        # Determine decision based on trust and risk
        decision_matrix = {
            (RiskLevel.MINIMAL, 'high_trust'): AccessDecision.ALLOW,
            (RiskLevel.MINIMAL, 'medium_trust'): AccessDecision.ALLOW,
            (RiskLevel.MINIMAL, 'low_trust'): AccessDecision.CONDITIONAL,
            
            (RiskLevel.LOW, 'high_trust'): AccessDecision.ALLOW,
            (RiskLevel.LOW, 'medium_trust'): AccessDecision.CONDITIONAL,
            (RiskLevel.LOW, 'low_trust'): AccessDecision.STEP_UP,
            
            (RiskLevel.MEDIUM, 'high_trust'): AccessDecision.CONDITIONAL,
            (RiskLevel.MEDIUM, 'medium_trust'): AccessDecision.STEP_UP,
            (RiskLevel.MEDIUM, 'low_trust'): AccessDecision.DENY,
            
            (RiskLevel.HIGH, 'high_trust'): AccessDecision.STEP_UP,
            (RiskLevel.HIGH, 'medium_trust'): AccessDecision.DENY,
            (RiskLevel.HIGH, 'low_trust'): AccessDecision.DENY,
            
            (RiskLevel.CRITICAL, 'high_trust'): AccessDecision.DENY,
            (RiskLevel.CRITICAL, 'medium_trust'): AccessDecision.DENY,
            (RiskLevel.CRITICAL, 'low_trust'): AccessDecision.DENY,
        }
        
        trust_category = 'high_trust' if composite_trust >= 0.7 else 'medium_trust' if composite_trust >= 0.4 else 'low_trust'
        decision = decision_matrix.get((context_risk, trust_category), AccessDecision.DENY)
        
        # Calculate confidence
        confidence = min(0.95, 0.5 + (composite_trust * 0.4) + (0.1 if context_risk.value <= 2 else -0.1))
        
        # Set expiration based on trust and risk
        expiration = None
        if decision == AccessDecision.ALLOW:
            if context_risk.value <= 2 and composite_trust >= 0.7:
                expiration = datetime.now() + timedelta(hours=8)
            else:
                expiration = datetime.now() + timedelta(hours=1)
        
        return AccessDecisionResult(
            decision=decision,
            confidence=confidence,
            risk_level=context_risk,
            conditions=[],
            expiration=expiration,
            audit_trail=[],
            reasoning=f"Composite trust: {composite_trust:.2f}, Risk: {context_risk.name}"
        )
    
    async def apply_conditional_access(self, request: AccessRequest, 
                                     decision: AccessDecisionResult) -> AccessDecisionResult:
        """Apply conditional access requirements"""
        conditions = []
        
        # Add common conditional requirements
        if decision.risk_level.value >= RiskLevel.MEDIUM.value:
            conditions.append("require_mfa_verification")
        
        if not request.device.is_managed:
            conditions.append("require_device_compliance_check")
        
        if request.resource.sensitivity_level == 'highly_confidential':
            conditions.append("require_manager_approval")
            conditions.append("limit_session_duration_30min")
        
        decision.conditions = conditions
        return decision
    
    def _get_required_roles(self, resource: Resource) -> List[str]:
        """Get required roles for resource access"""
        role_mappings = {
            'financial_data': ['finance_user', 'accountant', 'cfo'],
            'hr_data': ['hr_user', 'manager', 'ciso'],
            'source_code': ['developer', 'architect', 'cto'],
            'customer_data': ['sales_user', 'support_user', 'data_analyst']
        }
        return role_mappings.get(resource.data_classification, ['authenticated_user'])
    
    def _is_location_allowed(self, location: str, resource: Resource) -> bool:
        """Check if location is allowed for resource access"""
        # Simplified location check
        restricted_locations = ['CN', 'RU', 'KP']  # Country codes
        return location not in restricted_locations
    
    def _load_policies(self):
        """Load access policies from configuration"""
        # In production, this would load from a policy store
        self.policy_rules = [
            {
                'id': 'financial_data_access',
                'resource_type': 'financial_data',
                'required_roles': ['finance_user', 'accountant'],
                'min_trust_level': TrustLevel.HIGH,
                'additional_requirements': ['mfa_required']
            },
            {
                'id': 'source_code_access',
                'resource_type': 'source_code',
                'required_roles': ['developer', 'architect'],
                'min_trust_level': TrustLevel.MEDIUM,
                'time_restrictions': {'allowed_hours': range(6, 22)}
            }
        ]

class RiskCalculator:
    """Calculate risk scores based on various factors"""
    
    def calculate_user_risk(self, identity: Identity, historical_data: Dict) -> float:
        risk_score = 0.0
        
        # Check for recent failed logins
        if historical_data.get('failed_logins_24h', 0) > 3:
            risk_score += 0.3
        
        # Check for unusual activity patterns
        if historical_data.get('unusual_activity', False):
            risk_score += 0.4
        
        # Check for compromised credentials
        if historical_data.get('credentials_compromised', False):
            risk_score += 0.8
        
        return min(1.0, risk_score)

class TrustEvaluator:
    """Evaluate trust levels for identities and devices"""
    
    def evaluate_identity_trust(self, identity: Identity) -> TrustLevel:
        # Implementation for trust evaluation
        return identity.trust_level
    
    def evaluate_device_trust(self, device: Device) -> TrustLevel:
        # Implementation for device trust evaluation
        return device.trust_level

class ContextAnalyzer:
    """Analyze contextual information for risk assessment"""
    
    def analyze_access_pattern(self, request: AccessRequest) -> Dict[str, Any]:
        return {
            'is_unusual': False,
            'risk_indicators': [],
            'behavioral_score': 0.5
        }

class AuditLogger:
    """Comprehensive audit logging for zero trust decisions"""
    
    def log_access_request(self, request: AccessRequest):
        logging.info(f"Access request: {request.request_id} from {request.identity.user_id}")
    
    async def log_access_decision(self, request: AccessRequest, decision: AccessDecisionResult):
        audit_entry = {
            'request_id': request.request_id,
            'user_id': request.identity.user_id,
            'resource_id': request.resource.resource_id,
            'decision': decision.decision.value,
            'confidence': decision.confidence,
            'risk_level': decision.risk_level.name,
            'reasoning': decision.reasoning,
            'timestamp': datetime.now().isoformat(),
            'conditions': decision.conditions
        }
        logging.info(f"Access decision logged: {json.dumps(audit_entry)}")

# Usage example
async def demonstrate_zero_trust_evaluation():
    # Initialize policy engine
    config = {
        'default_session_timeout': 3600,
        'high_risk_timeout': 1800,
        'mfa_required_risk_threshold': 0.6
    }
    
    policy_engine = ZeroTrustPolicyEngine(config)
    
    # Create sample identity
    identity = Identity(
        user_id="user123",
        username="john.doe",
        roles=["developer", "authenticated_user"],
        groups=["engineering", "full_time"],
        trust_level=TrustLevel.MEDIUM,
        last_authentication=datetime.now() - timedelta(hours=2),
        authentication_methods=["password", "mfa"],
        risk_score=0.3,
        attributes={"department": "engineering", "clearance_level": "standard"}
    )
    
    # Create sample device
    device = Device(
        device_id="device456",
        device_type="laptop",
        os_version="Windows 11",
        is_managed=True,
        compliance_status="compliant",
        trust_level=TrustLevel.HIGH,
        last_seen=datetime.now(),
        location="US-CA",
        risk_factors=[]
    )
    
    # Create sample resource
    resource = Resource(
        resource_id="source_repo_1",
        resource_type="source_code",
        classification="internal",
        sensitivity_level="confidential",
        required_trust_level=TrustLevel.MEDIUM,
        access_policies=["role_based", "time_restricted"],
        data_classification="source_code"
    )
    
    # Create access request
    request = AccessRequest(
        request_id="req_789",
        identity=identity,
        device=device,
        resource=resource,
        requested_action="read",
        context={"purpose": "code_review", "project": "web_app"},
        timestamp=datetime.now(),
        source_ip="192.168.1.100",
        user_agent="Mozilla/5.0 (Windows NT 10.0; Win64; x64)"
    )
    
    # Evaluate access request
    decision = await policy_engine.evaluate_access_request(request)
    
    print(f"Access Decision: {decision.decision.value}")
    print(f"Confidence: {decision.confidence:.2f}")
    print(f"Risk Level: {decision.risk_level.name}")
    print(f"Conditions: {decision.conditions}")
    print(f"Reasoning: {decision.reasoning}")
    
    return decision

if __name__ == "__main__":
    import asyncio
    asyncio.run(demonstrate_zero_trust_evaluation())

import crypto from 'crypto';
import fs from 'fs';
import tls from 'tls';
import { EventEmitter } from 'events';

interface ServiceIdentity {
  serviceId: string;
  namespace: string;
  cluster: string;
  certificates: ServiceCertificates;
  trustLevel: TrustLevel;
  lastRotation: Date;
  nextRotation: Date;
}

interface ServiceCertificates {
  certificate: Buffer;
  privateKey: Buffer;
  caCertificate: Buffer;
  serialNumber: string;
  validFrom: Date;
  validTo: Date;
}

interface SecurityPolicy {
  policyId: string;
  sourceServices: string[];
  destinationServices: string[];
  allowedMethods: string[];
  requiredAuth: AuthenticationLevel;
  encryptionRequired: boolean;
  rateLimit?: RateLimit;
  conditions: PolicyCondition[];
}

interface PolicyCondition {
  type: 'time' | 'location' | 'attribute' | 'custom';
  operator: 'equals' | 'not_equals' | 'in' | 'not_in' | 'matches';
  value: any;
}

interface RateLimit {
  requestsPerSecond: number;
  burstSize: number;
  windowSize: number;
}

enum TrustLevel {
  UNTRUSTED = 0,
  LOW = 1,
  MEDIUM = 2,
  HIGH = 3,
  VERIFIED = 4
}

enum AuthenticationLevel {
  NONE = 0,
  BASIC = 1,
  MUTUAL_TLS = 2,
  JWT_TOKEN = 3,
  OAUTH2 = 4
}

interface TrafficMetrics {
  serviceId: string;
  requestCount: number;
  errorRate: number;
  latency: number;
  encryptedConnections: number;
  unauthorizedAttempts: number;
  policyViolations: number;
}

class ServiceMeshSecurityController extends EventEmitter {
  private serviceIdentities: Map<string, ServiceIdentity> = new Map();
  private securityPolicies: Map<string, SecurityPolicy> = new Map();
  private trafficMetrics: Map<string, TrafficMetrics> = new Map();
  private certificateAuthority: CertificateAuthority;
  private policyEnforcer: PolicyEnforcer;

  constructor() {
    super();
    this.certificateAuthority = new CertificateAuthority();
    this.policyEnforcer = new PolicyEnforcer();
    this.startCertificateRotation();
    this.startMetricsCollection();
  }

  async registerService(
    serviceId: string,
    namespace: string,
    cluster: string,
    trustLevel: TrustLevel = TrustLevel.MEDIUM
  ): Promise<ServiceIdentity> {
    try {
      // Generate service certificates
      const certificates = await this.certificateAuthority.issueCertificate(
        serviceId,
        namespace,
        cluster,
        trustLevel
      );

      const identity: ServiceIdentity = {
        serviceId,
        namespace,
        cluster,
        certificates,
        trustLevel,
        lastRotation: new Date(),
        nextRotation: new Date(Date.now() + 30 * 24 * 60 * 60 * 1000) // 30 days
      };

      this.serviceIdentities.set(serviceId, identity);
      
      this.emit('serviceRegistered', {
        serviceId,
        namespace,
        cluster,
        trustLevel
      });

      return identity;
    } catch (error) {
      this.emit('serviceRegistrationError', {
        serviceId,
        error: error.message
      });
      throw error;
    }
  }

  async createSecurityPolicy(policy: SecurityPolicy): Promise<void> {
    // Validate policy
    const validation = await this.validateSecurityPolicy(policy);
    if (!validation.isValid) {
      throw new Error(`Invalid security policy: ${validation.errors.join(', ')}`);
    }

    this.securityPolicies.set(policy.policyId, policy);
    
    // Apply policy to mesh
    await this.policyEnforcer.deployPolicy(policy);
    
    this.emit('policyCreated', {
      policyId: policy.policyId,
      sourceServices: policy.sourceServices.length,
      destinationServices: policy.destinationServices.length
    });
  }

  async enforceTrafficSecurity(
    sourceService: string,
    destinationService: string,
    request: ServiceRequest
  ): Promise<SecurityDecision> {
    try {
      // 1. Verify service identities
      const sourceIdentity = this.serviceIdentities.get(sourceService);
      const destIdentity = this.serviceIdentities.get(destinationService);

      if (!sourceIdentity || !destIdentity) {
        return {
          allowed: false,
          reason: 'Service identity not found',
          requiredActions: ['register_service']
        };
      }

      // 2. Validate mTLS certificates
      const certValidation = await this.validateMutualTLS(
        sourceIdentity,
        destIdentity,
        request.tlsInfo
      );

      if (!certValidation.isValid) {
        return {
          allowed: false,
          reason: 'Certificate validation failed',
          requiredActions: ['renew_certificate']
        };
      }

      // 3. Apply security policies
      const policyDecision = await this.evaluateSecurityPolicies(
        sourceService,
        destinationService,
        request
      );

      if (!policyDecision.allowed) {
        return policyDecision;
      }

      // 4. Check rate limits
      const rateLimitDecision = await this.checkRateLimits(
        sourceService,
        destinationService,
        request
      );

      if (!rateLimitDecision.allowed) {
        return rateLimitDecision;
      }

      // 5. Log successful authorization
      await this.logSecurityDecision(sourceService, destinationService, true, request);

      return {
        allowed: true,
        reason: 'All security checks passed',
        requiredActions: [],
        conditions: policyDecision.conditions || []
      };

    } catch (error) {
      await this.logSecurityDecision(sourceService, destinationService, false, request, error.message);
      
      return {
        allowed: false,
        reason: `Security enforcement error: ${error.message}`,
        requiredActions: ['investigate_error']
      };
    }
  }

  async rotateCertificates(serviceId?: string): Promise<RotationResult[]> {
    const results: RotationResult[] = [];
    const servicesToRotate = serviceId ? 
      [this.serviceIdentities.get(serviceId)].filter(Boolean) : 
      Array.from(this.serviceIdentities.values());

    for (const identity of servicesToRotate) {
      try {
        // Generate new certificates
        const newCertificates = await this.certificateAuthority.issueCertificate(
          identity.serviceId,
          identity.namespace,
          identity.cluster,
          identity.trustLevel
        );

        // Update identity
        const oldCertificate = identity.certificates;
        identity.certificates = newCertificates;
        identity.lastRotation = new Date();
        identity.nextRotation = new Date(Date.now() + 30 * 24 * 60 * 60 * 1000);

        // Deploy new certificates to service
        await this.deployCertificates(identity);

        results.push({
          serviceId: identity.serviceId,
          success: true,
          oldSerialNumber: oldCertificate.serialNumber,
          newSerialNumber: newCertificates.serialNumber
        });

        this.emit('certificateRotated', {
          serviceId: identity.serviceId,
          serialNumber: newCertificates.serialNumber
        });

      } catch (error) {
        results.push({
          serviceId: identity.serviceId,
          success: false,
          error: error.message
        });

        this.emit('certificateRotationError', {
          serviceId: identity.serviceId,
          error: error.message
        });
      }
    }

    return results;
  }

  async generateSecurityReport(): Promise<SecurityReport> {
    const services = Array.from(this.serviceIdentities.values());
    const policies = Array.from(this.securityPolicies.values());
    const metrics = Array.from(this.trafficMetrics.values());

    // Certificate health
    const certificateHealth = this.analyzeCertificateHealth(services);
    
    // Policy effectiveness
    const policyEffectiveness = await this.analyzePolicyEffectiveness(policies, metrics);
    
    // Security incidents
    const securityIncidents = await this.analyzeSecurityIncidents(metrics);
    
    // Compliance status
    const complianceStatus = await this.assessComplianceStatus(services, policies);

    return {
      reportTimestamp: new Date(),
      summary: {
        totalServices: services.length,
        activePolicies: policies.length,
        encryptionCoverage: this.calculateEncryptionCoverage(metrics),
        overallSecurityScore: this.calculateOverallSecurityScore(
          certificateHealth,
          policyEffectiveness,
          securityIncidents,
          complianceStatus
        )
      },
      certificateHealth,
      policyEffectiveness,
      securityIncidents,
      complianceStatus,
      recommendations: this.generateSecurityRecommendations(
        certificateHealth,
        policyEffectiveness,
        securityIncidents
      )
    };
  }

  private async validateMutualTLS(
    sourceIdentity: ServiceIdentity,
    destIdentity: ServiceIdentity,
    tlsInfo: TLSConnectionInfo
  ): Promise<CertificateValidation> {
    const validation: CertificateValidation = {
      isValid: true,
      errors: [],
      trustLevel: TrustLevel.HIGH
    };

    // Check certificate expiration
    if (new Date() > sourceIdentity.certificates.validTo) {
      validation.isValid = false;
      validation.errors.push('Source certificate expired');
    }

    if (new Date() > destIdentity.certificates.validTo) {
      validation.isValid = false;
      validation.errors.push('Destination certificate expired');
    }

    // Verify certificate chain
    try {
      const sourceValid = await this.certificateAuthority.verifyCertificate(
        sourceIdentity.certificates.certificate,
        sourceIdentity.certificates.caCertificate
      );

      const destValid = await this.certificateAuthority.verifyCertificate(
        destIdentity.certificates.certificate,
        destIdentity.certificates.caCertificate
      );

      if (!sourceValid || !destValid) {
        validation.isValid = false;
        validation.errors.push('Certificate chain validation failed');
      }
    } catch (error) {
      validation.isValid = false;
      validation.errors.push(`Certificate verification error: ${error.message}`);
    }

    // Check TLS version and cipher suites
    if (tlsInfo.version < '1.3') {
      validation.isValid = false;
      validation.errors.push('TLS version below minimum required (1.3)');
    }

    const allowedCiphers = [
      'TLS_AES_256_GCM_SHA384',
      'TLS_CHACHA20_POLY1305_SHA256',
      'TLS_AES_128_GCM_SHA256'
    ];

    if (!allowedCiphers.includes(tlsInfo.cipher)) {
      validation.isValid = false;
      validation.errors.push(`Cipher suite not allowed: ${tlsInfo.cipher}`);
    }

    return validation;
  }

  private async evaluateSecurityPolicies(
    sourceService: string,
    destinationService: string,
    request: ServiceRequest
  ): Promise<SecurityDecision> {
    const applicablePolicies = Array.from(this.securityPolicies.values())
      .filter(policy => 
        this.matchesServicePattern(sourceService, policy.sourceServices) &&
        this.matchesServicePattern(destinationService, policy.destinationServices)
      );

    if (applicablePolicies.length === 0) {
      // Default deny if no policies match
      return {
        allowed: false,
        reason: 'No security policy found for service communication',
        requiredActions: ['create_security_policy']
      };
    }

    for (const policy of applicablePolicies) {
      // Check allowed methods
      if (!policy.allowedMethods.includes(request.method)) {
        return {
          allowed: false,
          reason: `Method ${request.method} not allowed by policy ${policy.policyId}`,
          requiredActions: ['use_allowed_method']
        };
      }

      // Check authentication requirements
      if (policy.requiredAuth > request.authLevel) {
        return {
          allowed: false,
          reason: `Insufficient authentication level for policy ${policy.policyId}`,
          requiredActions: ['upgrade_authentication']
        };
      }

      // Check encryption requirements
      if (policy.encryptionRequired && !request.isEncrypted) {
        return {
          allowed: false,
          reason: `Encryption required by policy ${policy.policyId}`,
          requiredActions: ['enable_encryption']
        };
      }

      // Evaluate policy conditions
      const conditionResult = await this.evaluatePolicyConditions(policy.conditions, request);
      if (!conditionResult.allowed) {
        return conditionResult;
      }
    }

    return {
      allowed: true,
      reason: 'All policy checks passed',
      requiredActions: []
    };
  }

  private matchesServicePattern(serviceId: string, patterns: string[]): boolean {
    return patterns.some(pattern => {
      if (pattern === '*') return true;
      if (pattern.includes('*')) {
        const regex = new RegExp(pattern.replace(/*/g, '.*'));
        return regex.test(serviceId);
      }
      return pattern === serviceId;
    });
  }

  private async evaluatePolicyConditions(
    conditions: PolicyCondition[],
    request: ServiceRequest
  ): Promise<SecurityDecision> {
    for (const condition of conditions) {
      let conditionMet = false;

      switch (condition.type) {
        case 'time':
          const currentHour = new Date().getHours();
          conditionMet = this.evaluateCondition(currentHour, condition.operator, condition.value);
          break;
          
        case 'attribute':
          const attributeValue = request.attributes[condition.value.attributeName];
          conditionMet = this.evaluateCondition(attributeValue, condition.operator, condition.value.expectedValue);
          break;
          
        case 'location':
          conditionMet = this.evaluateCondition(request.sourceLocation, condition.operator, condition.value);
          break;
          
        default:
          conditionMet = true; // Unknown condition types are ignored
      }

      if (!conditionMet) {
        return {
          allowed: false,
          reason: `Policy condition not met: ${condition.type}`,
          requiredActions: ['satisfy_policy_conditions']
        };
      }
    }

    return { allowed: true, reason: 'All conditions satisfied', requiredActions: [] };
  }

  private evaluateCondition(actual: any, operator: string, expected: any): boolean {
    switch (operator) {
      case 'equals':
        return actual === expected;
      case 'not_equals':
        return actual !== expected;
      case 'in':
        return Array.isArray(expected) && expected.includes(actual);
      case 'not_in':
        return Array.isArray(expected) && !expected.includes(actual);
      case 'matches':
        return new RegExp(expected).test(String(actual));
      default:
        return false;
    }
  }

  private startCertificateRotation(): void {
    // Check for certificates needing rotation every hour
    setInterval(async () => {
      const now = new Date();
      const servicesToRotate = Array.from(this.serviceIdentities.values())
        .filter(identity => now >= identity.nextRotation)
        .map(identity => identity.serviceId);

      if (servicesToRotate.length > 0) {
        console.log(`Rotating certificates for ${servicesToRotate.length} services`);
        await this.rotateCertificates();
      }
    }, 60 * 60 * 1000); // Every hour
  }

  private startMetricsCollection(): void {
    // Collect traffic metrics every 5 minutes
    setInterval(() => {
      this.collectTrafficMetrics();
    }, 5 * 60 * 1000); // Every 5 minutes
  }

  private async collectTrafficMetrics(): Promise<void> {
    // This would integrate with service mesh data plane
    // For demonstration, we'll simulate metrics collection
    console.log('Collecting service mesh traffic metrics...');
  }

  private calculateOverallSecurityScore(
    certificateHealth: any,
    policyEffectiveness: any,
    securityIncidents: any,
    complianceStatus: any
  ): number {
    // Weighted scoring algorithm
    const weights = {
      certificates: 0.3,
      policies: 0.25,
      incidents: 0.25,
      compliance: 0.2
    };

    const scores = {
      certificates: certificateHealth.healthScore || 0,
      policies: policyEffectiveness.effectivenessScore || 0,
      incidents: Math.max(0, 100 - (securityIncidents.criticalCount * 20)),
      compliance: complianceStatus.overallScore || 0
    };

    return Math.round(
      Object.entries(weights).reduce(
        (total, [key, weight]) => total + (scores[key] * weight),
        0
      )
    );
  }
}

// Supporting interfaces and classes
interface ServiceRequest {
  method: string;
  path: string;
  headers: { [key: string]: string };
  authLevel: AuthenticationLevel;
  isEncrypted: boolean;
  sourceLocation: string;
  attributes: { [key: string]: any };
  tlsInfo: TLSConnectionInfo;
}

interface TLSConnectionInfo {
  version: string;
  cipher: string;
  serverCertificate: Buffer;
  clientCertificate?: Buffer;
}

interface SecurityDecision {
  allowed: boolean;
  reason: string;
  requiredActions: string[];
  conditions?: string[];
}

interface CertificateValidation {
  isValid: boolean;
  errors: string[];
  trustLevel: TrustLevel;
}

interface RotationResult {
  serviceId: string;
  success: boolean;
  oldSerialNumber?: string;
  newSerialNumber?: string;
  error?: string;
}

interface SecurityReport {
  reportTimestamp: Date;
  summary: {
    totalServices: number;
    activePolicies: number;
    encryptionCoverage: number;
    overallSecurityScore: number;
  };
  certificateHealth: any;
  policyEffectiveness: any;
  securityIncidents: any;
  complianceStatus: any;
  recommendations: string[];
}

class CertificateAuthority {
  async issueCertificate(
    serviceId: string,
    namespace: string,
    cluster: string,
    trustLevel: TrustLevel
  ): Promise<ServiceCertificates> {
    // Generate key pair
    const keyPair = crypto.generateKeyPairSync('rsa', {
      modulusLength: 2048,
      publicKeyEncoding: { type: 'spki', format: 'pem' },
      privateKeyEncoding: { type: 'pkcs8', format: 'pem' }
    });

    // Create certificate (simplified - would use proper X.509 certificate generation)
    const serialNumber = crypto.randomBytes(16).toString('hex');
    const validFrom = new Date();
    const validTo = new Date(validFrom.getTime() + 30 * 24 * 60 * 60 * 1000); // 30 days

    return {
      certificate: Buffer.from(keyPair.publicKey),
      privateKey: Buffer.from(keyPair.privateKey),
      caCertificate: Buffer.from('ca-certificate-placeholder'),
      serialNumber,
      validFrom,
      validTo
    };
  }

  async verifyCertificate(certificate: Buffer, caCertificate: Buffer): Promise<boolean> {
    // Simplified certificate verification
    // In production, would use proper X.509 verification
    return true;
  }
}

class PolicyEnforcer {
  async deployPolicy(policy: SecurityPolicy): Promise<void> {
    // Deploy policy to service mesh control plane
    console.log(`Deploying security policy: ${policy.policyId}`);
  }
}

export { ServiceMeshSecurityController, SecurityPolicy, TrustLevel, AuthenticationLevel };