#!/usr/bin/env python3
"""
Enterprise Firewall Management and Automation Framework
"""

import subprocess
import json
import yaml
import logging
import time
import ipaddress
import threading
from typing import Dict, List, Optional, Tuple, Any, Union
from dataclasses import dataclass, asdict, field
from pathlib import Path
from enum import Enum
import concurrent.futures
import hashlib

class FirewallType(Enum):
    UFW = "ufw"
    IPTABLES = "iptables"
    NFTABLES = "nftables"
    FIREWALLD = "firewalld"

class RuleAction(Enum):
    ALLOW = "allow"
    DENY = "deny"
    REJECT = "reject"
    LOG = "log"

class RuleDirection(Enum):
    IN = "in"
    OUT = "out"
    FORWARD = "forward"

@dataclass
class FirewallRule:
    name: str
    action: RuleAction
    direction: RuleDirection
    protocol: str = "tcp"
    port: Optional[Union[int, str]] = None
    source: Optional[str] = None
    destination: Optional[str] = None
    interface: Optional[str] = None
    priority: int = 100
    enabled: bool = True
    description: str = ""
    compliance_tags: List[str] = field(default_factory=list)
    created_by: str = "system"
    created_at: float = field(default_factory=time.time)

@dataclass
class SecurityPolicy:
    name: str
    description: str
    rules: List[FirewallRule]
    environments: List[str]  # prod, staging, dev
    compliance_frameworks: List[str]  # PCI-DSS, HIPAA, SOX
    risk_level: str = "medium"  # low, medium, high, critical
    auto_apply: bool = False
    validation_required: bool = True

@dataclass
class NetworkZone:
    name: str
    description: str
    cidr_blocks: List[str]
    trust_level: str  # trusted, untrusted, dmz, internal
    default_policy: RuleAction
    allowed_services: List[str] = field(default_factory=list)
    security_groups: List[str] = field(default_factory=list)

class EnterpriseFirewallManager:
    def __init__(self, config_file: str = "/etc/firewall/enterprise-config.yaml"):
        self.config_file = Path(config_file)
        self.firewall_type = self._detect_firewall_type()
        self.policies: Dict[str, SecurityPolicy] = {}
        self.zones: Dict[str, NetworkZone] = {}
        self.active_rules: List[FirewallRule] = []
        
        self.logger = self._setup_logging()
        self.rule_cache = {}
        self.policy_violations = []
        
        self._load_configuration()
        self._initialize_firewall()
    
    def _setup_logging(self) -> logging.Logger:
        """Setup comprehensive firewall logging"""
        logger = logging.getLogger(__name__)
        logger.setLevel(logging.INFO)
        
        # Security audit log
        audit_handler = logging.FileHandler('/var/log/firewall/enterprise-audit.log')
        audit_formatter = logging.Formatter(
            '%(asctime)s - FIREWALL-AUDIT - %(levelname)s - %(message)s'
        )
        audit_handler.setFormatter(audit_formatter)
        
        # SIEM integration
        siem_handler = logging.handlers.SysLogHandler()
        siem_formatter = logging.Formatter(
            'ENTERPRISE-FW[%(process)d]: %(levelname)s - %(message)s'
        )
        siem_handler.setFormatter(siem_formatter)
        
        # Console output
        console_handler = logging.StreamHandler()
        console_formatter = logging.Formatter('%(levelname)s: %(message)s')
        console_handler.setFormatter(console_formatter)
        
        logger.addHandler(audit_handler)
        logger.addHandler(siem_handler)
        logger.addHandler(console_handler)
        
        return logger
    
    def _detect_firewall_type(self) -> FirewallType:
        """Auto-detect available firewall system"""
        firewall_priority = [
            (FirewallType.UFW, "ufw"),
            (FirewallType.FIREWALLD, "firewall-cmd"),
            (FirewallType.NFTABLES, "nft"),
            (FirewallType.IPTABLES, "iptables")
        ]
        
        for fw_type, command in firewall_priority:
            if self._command_exists(command):
                self.logger.info(f"Detected firewall type: {fw_type.value}")
                return fw_type
        
        # Default to iptables if nothing else found
        return FirewallType.IPTABLES
    
    def _load_configuration(self) -> None:
        """Load enterprise firewall configuration"""
        if self.config_file.exists():
            try:
                with open(self.config_file, 'r') as f:
                    config = yaml.safe_load(f)
                
                # Load security policies
                for policy_data in config.get('policies', []):
                    rules = []
                    for rule_data in policy_data.get('rules', []):
                        rule = FirewallRule(**rule_data)
                        rules.append(rule)
                    
                    policy_data['rules'] = rules
                    policy = SecurityPolicy(**policy_data)
                    self.policies[policy.name] = policy
                
                # Load network zones
                for zone_data in config.get('zones', []):
                    zone = NetworkZone(**zone_data)
                    self.zones[zone.name] = zone
                
                self.logger.info(f"Loaded {len(self.policies)} security policies and {len(self.zones)} network zones")
                
            except Exception as e:
                self.logger.error(f"Failed to load configuration: {e}")
                self._create_default_configuration()
        else:
            self._create_default_configuration()
    
    def _create_default_configuration(self) -> None:
        """Create default enterprise configuration"""
        # Default security policies
        ssh_policy = SecurityPolicy(
            name="ssh_access",
            description="SSH access management policy",
            rules=[
                FirewallRule(
                    name="allow_ssh_admin",
                    action=RuleAction.ALLOW,
                    direction=RuleDirection.IN,
                    protocol="tcp",
                    port=22,
                    source="10.0.0.0/8",
                    description="Allow SSH from admin networks",
                    compliance_tags=["CIS", "NIST"]
                )
            ],
            environments=["prod", "staging"],
            compliance_frameworks=["CIS", "NIST", "STIG"],
            risk_level="high"
        )
        
        web_policy = SecurityPolicy(
            name="web_services",
            description="Web service access policy",
            rules=[
                FirewallRule(
                    name="allow_http",
                    action=RuleAction.ALLOW,
                    direction=RuleDirection.IN,
                    protocol="tcp",
                    port=80,
                    description="Allow HTTP traffic"
                ),
                FirewallRule(
                    name="allow_https",
                    action=RuleAction.ALLOW,
                    direction=RuleDirection.IN,
                    protocol="tcp",
                    port=443,
                    description="Allow HTTPS traffic"
                )
            ],
            environments=["prod", "staging", "dev"],
            compliance_frameworks=["PCI-DSS"],
            auto_apply=True
        )
        
        self.policies["ssh_access"] = ssh_policy
        self.policies["web_services"] = web_policy
        
        # Default network zones
        trusted_zone = NetworkZone(
            name="trusted",
            description="Trusted internal network",
            cidr_blocks=["10.0.0.0/8", "172.16.0.0/12"],
            trust_level="trusted",
            default_policy=RuleAction.ALLOW,
            allowed_services=["ssh", "http", "https", "dns"]
        )
        
        dmz_zone = NetworkZone(
            name="dmz",
            description="Demilitarized zone",
            cidr_blocks=["192.168.100.0/24"],
            trust_level="dmz",
            default_policy=RuleAction.DENY,
            allowed_services=["http", "https"]
        )
        
        self.zones["trusted"] = trusted_zone
        self.zones["dmz"] = dmz_zone
        
        self.logger.info("Created default enterprise firewall configuration")
    
    def save_configuration(self) -> None:
        """Save current configuration to file"""
        config = {
            'policies': [],
            'zones': []
        }
        
        # Convert policies to serializable format
        for policy in self.policies.values():
            policy_dict = asdict(policy)
            # Convert rules to dict format
            policy_dict['rules'] = [asdict(rule) for rule in policy.rules]
            config['policies'].append(policy_dict)
        
        # Convert zones to serializable format
        for zone in self.zones.values():
            config['zones'].append(asdict(zone))
        
        # Ensure directory exists
        self.config_file.parent.mkdir(parents=True, exist_ok=True)
        
        with open(self.config_file, 'w') as f:
            yaml.dump(config, f, default_flow_style=False)
        
        self.config_file.chmod(0o600)
        self.logger.info("Configuration saved")
    
    def _initialize_firewall(self) -> None:
        """Initialize firewall system"""
        try:
            if self.firewall_type == FirewallType.UFW:
                self._initialize_ufw()
            elif self.firewall_type == FirewallType.FIREWALLD:
                self._initialize_firewalld()
            elif self.firewall_type == FirewallType.NFTABLES:
                self._initialize_nftables()
            else:
                self._initialize_iptables()
                
            self.logger.info(f"Firewall {self.firewall_type.value} initialized successfully")
            
        except Exception as e:
            self.logger.error(f"Failed to initialize firewall: {e}")
            raise
    
    def _initialize_ufw(self) -> None:
        """Initialize UFW firewall"""
        # Check if UFW is installed
        if not self._command_exists("ufw"):
            self._install_package("ufw")
        
        # Reset UFW to clean state
        subprocess.run(['ufw', '--force', 'reset'], check=True, capture_output=True)
        
        # Set default policies
        subprocess.run(['ufw', 'default', 'deny', 'incoming'], check=True)
        subprocess.run(['ufw', 'default', 'allow', 'outgoing'], check=True)
        subprocess.run(['ufw', 'default', 'deny', 'forward'], check=True)
        
        # Enable logging
        subprocess.run(['ufw', 'logging', 'on'], check=True)
        
        # Don't enable UFW yet - will be done after rules are applied
    
    def _initialize_firewalld(self) -> None:
        """Initialize firewalld"""
        if not self._command_exists("firewall-cmd"):
            self._install_package("firewalld")
        
        # Start firewalld service
        subprocess.run(['systemctl', 'enable', 'firewalld'], check=True)
        subprocess.run(['systemctl', 'start', 'firewalld'], check=True)
        
        # Set default zone to drop
        subprocess.run(['firewall-cmd', '--set-default-zone=drop'], check=True)
    
    def _initialize_nftables(self) -> None:
        """Initialize nftables"""
        if not self._command_exists("nft"):
            self._install_package("nftables")
        
        # Create basic nftables configuration
        nft_config = """
table inet filter {
    chain input {
        type filter hook input priority 0; policy drop;
        
        # Allow loopback
        iif lo accept
        
        # Allow established connections
        ct state established,related accept
        
        # Allow ICMP
        ip protocol icmp accept
        ip6 nexthdr ipv6-icmp accept
    }
    
    chain forward {
        type filter hook forward priority 0; policy drop;
    }
    
    chain output {
        type filter hook output priority 0; policy accept;
    }
}
"""
        
        # Apply base configuration
        with open('/tmp/nft_base.conf', 'w') as f:
            f.write(nft_config)
        
        subprocess.run(['nft', '-f', '/tmp/nft_base.conf'], check=True)
        Path('/tmp/nft_base.conf').unlink()
    
    def _initialize_iptables(self) -> None:
        """Initialize iptables"""
        # Install iptables-persistent for rule persistence
        if self._is_debian_based():
            self._install_package("iptables-persistent")
        
        # Flush existing rules
        subprocess.run(['iptables', '-F'], check=True)
        subprocess.run(['iptables', '-X'], check=True)
        subprocess.run(['ip6tables', '-F'], check=True)
        subprocess.run(['ip6tables', '-X'], check=True)
        
        # Set default policies
        subprocess.run(['iptables', '-P', 'INPUT', 'DROP'], check=True)
        subprocess.run(['iptables', '-P', 'FORWARD', 'DROP'], check=True)
        subprocess.run(['iptables', '-P', 'OUTPUT', 'ACCEPT'], check=True)
        
        subprocess.run(['ip6tables', '-P', 'INPUT', 'DROP'], check=True)
        subprocess.run(['ip6tables', '-P', 'FORWARD', 'DROP'], check=True)
        subprocess.run(['ip6tables', '-P', 'OUTPUT', 'ACCEPT'], check=True)
        
        # Allow loopback and established connections
        basic_rules = [
            ['iptables', '-A', 'INPUT', '-i', 'lo', '-j', 'ACCEPT'],
            ['iptables', '-A', 'INPUT', '-m', 'conntrack', '--ctstate', 'ESTABLISHED,RELATED', '-j', 'ACCEPT'],
            ['iptables', '-A', 'INPUT', '-p', 'icmp', '-j', 'ACCEPT'],
            ['ip6tables', '-A', 'INPUT', '-i', 'lo', '-j', 'ACCEPT'],
            ['ip6tables', '-A', 'INPUT', '-m', 'conntrack', '--ctstate', 'ESTABLISHED,RELATED', '-j', 'ACCEPT'],
            ['ip6tables', '-A', 'INPUT', '-p', 'ipv6-icmp', '-j', 'ACCEPT']
        ]
        
        for rule in basic_rules:
            subprocess.run(rule, check=True)
    
    def apply_security_policy(self, policy_name: str, validate: bool = True) -> bool:
        """Apply a security policy"""
        if policy_name not in self.policies:
            self.logger.error(f"Security policy '{policy_name}' not found")
            return False
        
        policy = self.policies[policy_name]
        
        if validate and policy.validation_required:
            if not self._validate_policy(policy):
                self.logger.error(f"Policy validation failed for '{policy_name}'")
                return False
        
        self.logger.info(f"Applying security policy: {policy_name}")
        
        success_count = 0
        total_rules = len(policy.rules)
        
        for rule in policy.rules:
            if rule.enabled:
                if self._apply_rule(rule):
                    success_count += 1
                    self.active_rules.append(rule)
                else:
                    self.logger.warning(f"Failed to apply rule: {rule.name}")
        
        # Log policy application
        self.logger.info(f"Applied {success_count}/{total_rules} rules from policy '{policy_name}'")
        
        if success_count == total_rules:
            self._log_security_event("POLICY_APPLIED", f"Successfully applied policy: {policy_name}")
            return True
        else:
            self._log_security_event("POLICY_PARTIAL", f"Partially applied policy: {policy_name} ({success_count}/{total_rules})")
            return False
    
    def _apply_rule(self, rule: FirewallRule) -> bool:
        """Apply a single firewall rule"""
        try:
            if self.firewall_type == FirewallType.UFW:
                return self._apply_ufw_rule(rule)
            elif self.firewall_type == FirewallType.FIREWALLD:
                return self._apply_firewalld_rule(rule)
            elif self.firewall_type == FirewallType.NFTABLES:
                return self._apply_nftables_rule(rule)
            else:
                return self._apply_iptables_rule(rule)
                
        except Exception as e:
            self.logger.error(f"Error applying rule {rule.name}: {e}")
            return False
    
    def _apply_ufw_rule(self, rule: FirewallRule) -> bool:
        """Apply rule using UFW"""
        cmd = ['ufw']
        
        # Add action
        if rule.action == RuleAction.ALLOW:
            cmd.append('allow')
        elif rule.action == RuleAction.DENY:
            cmd.append('deny')
        elif rule.action == RuleAction.REJECT:
            cmd.append('reject')
        
        # Add direction
        if rule.direction == RuleDirection.IN:
            cmd.append('in')
        elif rule.direction == RuleDirection.OUT:
            cmd.append('out')
        
        # Add interface
        if rule.interface:
            cmd.extend(['on', rule.interface])
        
        # Add source
        if rule.source:
            cmd.extend(['from', rule.source])
        
        # Add destination and port
        if rule.destination:
            if rule.port:
                cmd.extend(['to', rule.destination, 'port', str(rule.port)])
            else:
                cmd.extend(['to', rule.destination])
        elif rule.port:
            cmd.extend(['to', 'any', 'port', str(rule.port)])
        
        # Add protocol
        if rule.protocol and rule.protocol != 'tcp':
            cmd.extend(['proto', rule.protocol])
        
        result = subprocess.run(cmd, capture_output=True, text=True)
        
        if result.returncode == 0:
            self.logger.debug(f"UFW rule applied: {' '.join(cmd)}")
            return True
        else:
            self.logger.error(f"UFW rule failed: {result.stderr}")
            return False
    
    def _apply_firewalld_rule(self, rule: FirewallRule) -> bool:
        """Apply rule using firewalld"""
        zone = "public"  # Default zone, could be made configurable
        
        cmd = ['firewall-cmd', f'--zone={zone}']
        
        if rule.action == RuleAction.ALLOW:
            if rule.port:
                cmd.extend(['--add-port', f"{rule.port}/{rule.protocol}"])
            elif rule.source:
                cmd.extend(['--add-source', rule.source])
        elif rule.action in [RuleAction.DENY, RuleAction.REJECT]:
            # firewalld uses rich rules for deny/reject
            rich_rule = f'rule family="ipv4"'
            
            if rule.source:
                rich_rule += f' source address="{rule.source}"'
            
            if rule.port:
                rich_rule += f' port protocol="{rule.protocol}" port="{rule.port}"'
            
            if rule.action == RuleAction.DENY:
                rich_rule += ' drop'
            else:
                rich_rule += ' reject'
            
            cmd.extend(['--add-rich-rule', rich_rule])
        
        cmd.append('--permanent')
        
        result = subprocess.run(cmd, capture_output=True, text=True)
        
        if result.returncode == 0:
            # Reload firewalld to apply permanent rules
            subprocess.run(['firewall-cmd', '--reload'], check=True)
            self.logger.debug(f"Firewalld rule applied: {' '.join(cmd)}")
            return True
        else:
            self.logger.error(f"Firewalld rule failed: {result.stderr}")
            return False
    
    def _apply_nftables_rule(self, rule: FirewallRule) -> bool:
        """Apply rule using nftables"""
        table = "inet filter"
        
        if rule.direction == RuleDirection.IN:
            chain = "input"
        elif rule.direction == RuleDirection.OUT:
            chain = "output"
        else:
            chain = "forward"
        
        # Build nftables rule
        nft_rule = f"add rule {table} {chain}"
        
        # Add source
        if rule.source:
            if self._is_ipv6_address(rule.source):
                nft_rule += f" ip6 saddr {rule.source}"
            else:
                nft_rule += f" ip saddr {rule.source}"
        
        # Add destination
        if rule.destination:
            if self._is_ipv6_address(rule.destination):
                nft_rule += f" ip6 daddr {rule.destination}"
            else:
                nft_rule += f" ip daddr {rule.destination}"
        
        # Add protocol and port
        if rule.protocol:
            nft_rule += f" {rule.protocol}"
            
            if rule.port:
                nft_rule += f" dport {rule.port}"
        
        # Add action
        if rule.action == RuleAction.ALLOW:
            nft_rule += " accept"
        elif rule.action == RuleAction.DENY:
            nft_rule += " drop"
        elif rule.action == RuleAction.REJECT:
            nft_rule += " reject"
        
        result = subprocess.run(['nft', nft_rule], capture_output=True, text=True)
        
        if result.returncode == 0:
            self.logger.debug(f"Nftables rule applied: {nft_rule}")
            return True
        else:
            self.logger.error(f"Nftables rule failed: {result.stderr}")
            return False
    
    def _apply_iptables_rule(self, rule: FirewallRule) -> bool:
        """Apply rule using iptables"""
        # Determine if IPv4 or IPv6
        is_ipv6 = (rule.source and self._is_ipv6_address(rule.source)) or \
                  (rule.destination and self._is_ipv6_address(rule.destination))
        
        iptables_cmd = 'ip6tables' if is_ipv6 else 'iptables'
        
        # Determine chain
        if rule.direction == RuleDirection.IN:
            chain = "INPUT"
        elif rule.direction == RuleDirection.OUT:
            chain = "OUTPUT"
        else:
            chain = "FORWARD"
        
        cmd = [iptables_cmd, '-A', chain]
        
        # Add interface
        if rule.interface:
            if rule.direction == RuleDirection.IN:
                cmd.extend(['-i', rule.interface])
            else:
                cmd.extend(['-o', rule.interface])
        
        # Add source
        if rule.source:
            cmd.extend(['-s', rule.source])
        
        # Add destination
        if rule.destination:
            cmd.extend(['-d', rule.destination])
        
        # Add protocol
        if rule.protocol:
            cmd.extend(['-p', rule.protocol])
            
            # Add port
            if rule.port:
                if rule.direction == RuleDirection.IN:
                    cmd.extend(['--dport', str(rule.port)])
                else:
                    cmd.extend(['--sport', str(rule.port)])
        
        # Add action
        if rule.action == RuleAction.ALLOW:
            cmd.extend(['-j', 'ACCEPT'])
        elif rule.action == RuleAction.DENY:
            cmd.extend(['-j', 'DROP'])
        elif rule.action == RuleAction.REJECT:
            cmd.extend(['-j', 'REJECT'])
        elif rule.action == RuleAction.LOG:
            cmd.extend(['-j', 'LOG', '--log-prefix', f'FW-{rule.name}: '])
        
        result = subprocess.run(cmd, capture_output=True, text=True)
        
        if result.returncode == 0:
            self.logger.debug(f"Iptables rule applied: {' '.join(cmd)}")
            return True
        else:
            self.logger.error(f"Iptables rule failed: {result.stderr}")
            return False
    
    def enable_firewall(self) -> bool:
        """Enable the firewall"""
        try:
            if self.firewall_type == FirewallType.UFW:
                result = subprocess.run(['ufw', '--force', 'enable'], 
                                      capture_output=True, text=True)
                if result.returncode == 0:
                    self.logger.info("UFW firewall enabled")
                    return True
            
            elif self.firewall_type == FirewallType.FIREWALLD:
                subprocess.run(['systemctl', 'enable', 'firewalld'], check=True)
                subprocess.run(['systemctl', 'start', 'firewalld'], check=True)
                self.logger.info("Firewalld enabled")
                return True
            
            elif self.firewall_type == FirewallType.NFTABLES:
                subprocess.run(['systemctl', 'enable', 'nftables'], check=True)
                subprocess.run(['systemctl', 'start', 'nftables'], check=True)
                # Save current rules
                subprocess.run(['nft', 'list', 'ruleset'], 
                             stdout=open('/etc/nftables.conf', 'w'), check=True)
                self.logger.info("Nftables enabled")
                return True
            
            else:  # iptables
                if self._is_debian_based():
                    subprocess.run(['iptables-save'], 
                                 stdout=open('/etc/iptables/rules.v4', 'w'), check=True)
                    subprocess.run(['ip6tables-save'], 
                                 stdout=open('/etc/iptables/rules.v6', 'w'), check=True)
                    subprocess.run(['systemctl', 'enable', 'netfilter-persistent'], check=True)
                else:
                    subprocess.run(['iptables-save'], 
                                 stdout=open('/etc/sysconfig/iptables', 'w'), check=True)
                    subprocess.run(['ip6tables-save'], 
                                 stdout=open('/etc/sysconfig/ip6tables', 'w'), check=True)
                
                self.logger.info("Iptables rules saved and persistence enabled")
                return True
                
        except Exception as e:
            self.logger.error(f"Failed to enable firewall: {e}")
            return False
    
    def get_firewall_status(self) -> Dict[str, Any]:
        """Get comprehensive firewall status"""
        status = {
            'firewall_type': self.firewall_type.value,
            'enabled': False,
            'rule_count': 0,
            'active_policies': [],
            'zones': [],
            'last_modified': None,
            'compliance_status': {}
        }
        
        try:
            if self.firewall_type == FirewallType.UFW:
                result = subprocess.run(['ufw', 'status', 'verbose'], 
                                      capture_output=True, text=True)
                status['enabled'] = 'Status: active' in result.stdout
                status['rule_count'] = result.stdout.count('ALLOW') + result.stdout.count('DENY')
            
            elif self.firewall_type == FirewallType.FIREWALLD:
                result = subprocess.run(['firewall-cmd', '--state'], 
                                      capture_output=True, text=True)
                status['enabled'] = result.returncode == 0
                
                if status['enabled']:
                    # Get rule count
                    zones_result = subprocess.run(['firewall-cmd', '--get-active-zones'], 
                                                capture_output=True, text=True)
                    status['zones'] = zones_result.stdout.strip().split('\n')
            
            elif self.firewall_type == FirewallType.NFTABLES:
                result = subprocess.run(['nft', 'list', 'ruleset'], 
                                      capture_output=True, text=True)
                status['enabled'] = len(result.stdout) > 0
                status['rule_count'] = result.stdout.count('accept') + result.stdout.count('drop')
            
            else:  # iptables
                result = subprocess.run(['iptables', '-L'], 
                                      capture_output=True, text=True)
                status['enabled'] = 'DROP' in result.stdout or 'REJECT' in result.stdout
                status['rule_count'] = result.stdout.count('ACCEPT') + result.stdout.count('DROP')
            
            # Get active policies
            status['active_policies'] = list(self.policies.keys())
            
            # Check compliance
            status['compliance_status'] = self._check_compliance()
            
        except Exception as e:
            self.logger.error(f"Error getting firewall status: {e}")
        
        return status
    
    def _validate_policy(self, policy: SecurityPolicy) -> bool:
        """Validate security policy before application"""
        validation_errors = []
        
        # Check for conflicting rules
        for i, rule1 in enumerate(policy.rules):
            for j, rule2 in enumerate(policy.rules[i+1:], i+1):
                if self._rules_conflict(rule1, rule2):
                    validation_errors.append(f"Conflicting rules: {rule1.name} and {rule2.name}")
        
        # Validate IP addresses and networks
        for rule in policy.rules:
            if rule.source and not self._is_valid_network(rule.source):
                validation_errors.append(f"Invalid source network in rule {rule.name}: {rule.source}")
            
            if rule.destination and not self._is_valid_network(rule.destination):
                validation_errors.append(f"Invalid destination network in rule {rule.name}: {rule.destination}")
            
            if rule.port and not self._is_valid_port(rule.port):
                validation_errors.append(f"Invalid port in rule {rule.name}: {rule.port}")
        
        # Check for security risks
        risky_rules = self._identify_risky_rules(policy.rules)
        if risky_rules and policy.risk_level in ["low", "medium"]:
            validation_errors.extend([f"High-risk rule in {policy.risk_level} policy: {rule}" for rule in risky_rules])
        
        if validation_errors:
            for error in validation_errors:
                self.logger.warning(f"Policy validation error: {error}")
            return False
        
        return True
    
    def _rules_conflict(self, rule1: FirewallRule, rule2: FirewallRule) -> bool:
        """Check if two rules conflict with each other"""
        # Rules conflict if they have opposite actions for the same traffic
        if (rule1.action in [RuleAction.ALLOW] and rule2.action in [RuleAction.DENY, RuleAction.REJECT]) or \
           (rule1.action in [RuleAction.DENY, RuleAction.REJECT] and rule2.action in [RuleAction.ALLOW]):
            
            # Check if they target the same traffic
            same_direction = rule1.direction == rule2.direction
            same_protocol = rule1.protocol == rule2.protocol
            same_port = rule1.port == rule2.port
            
            # Check source/destination overlap
            source_overlap = self._networks_overlap(rule1.source, rule2.source)
            dest_overlap = self._networks_overlap(rule1.destination, rule2.destination)
            
            return same_direction and same_protocol and same_port and source_overlap and dest_overlap
        
        return False
    
    def _networks_overlap(self, net1: Optional[str], net2: Optional[str]) -> bool:
        """Check if two networks overlap"""
        if not net1 or not net2:
            return True  # Consider None as "any" which overlaps with everything
        
        try:
            network1 = ipaddress.ip_network(net1, strict=False)
            network2 = ipaddress.ip_network(net2, strict=False)
            return network1.overlaps(network2)
        except:
            return False
    
    def _identify_risky_rules(self, rules: List[FirewallRule]) -> List[str]:
        """Identify potentially risky firewall rules"""
        risky_rules = []
        
        for rule in rules:
            # Check for overly permissive rules
            if rule.action == RuleAction.ALLOW:
                if rule.source in [None, "0.0.0.0/0", "::/0", "any"]:
                    if rule.port in [22, 3389, 23, 21]:  # SSH, RDP, Telnet, FTP
                        risky_rules.append(f"{rule.name}: Allows admin access from anywhere")
                    elif not rule.port:
                        risky_rules.append(f"{rule.name}: Allows all traffic from anywhere")
        
        return risky_rules
    
    def _check_compliance(self) -> Dict[str, Any]:
        """Check compliance with security frameworks"""
        compliance_status = {
            'CIS': {'score': 0, 'total': 0, 'passed': [], 'failed': []},
            'NIST': {'score': 0, 'total': 0, 'passed': [], 'failed': []},
            'PCI-DSS': {'score': 0, 'total': 0, 'passed': [], 'failed': []}
        }
        
        # CIS Controls checks
        cis_checks = [
            ('default_deny', self._check_default_deny_policy(), "Default deny policy configured"),
            ('logging_enabled', self._check_logging_enabled(), "Firewall logging enabled"),
            ('admin_access_restricted', self._check_admin_access_restricted(), "Administrative access restricted")
        ]
        
        for check_name, passed, description in cis_checks:
            compliance_status['CIS']['total'] += 1
            if passed:
                compliance_status['CIS']['score'] += 1
                compliance_status['CIS']['passed'].append(description)
            else:
                compliance_status['CIS']['failed'].append(description)
        
        # NIST checks (similar structure)
        nist_checks = [
            ('network_segmentation', self._check_network_segmentation(), "Network segmentation implemented"),
            ('access_control', self._check_access_control(), "Access control mechanisms in place")
        ]
        
        for check_name, passed, description in nist_checks:
            compliance_status['NIST']['total'] += 1
            if passed:
                compliance_status['NIST']['score'] += 1
                compliance_status['NIST']['passed'].append(description)
            else:
                compliance_status['NIST']['failed'].append(description)
        
        return compliance_status
    
    def _check_default_deny_policy(self) -> bool:
        """Check if default deny policy is configured"""
        try:
            if self.firewall_type == FirewallType.UFW:
                result = subprocess.run(['ufw', 'status', 'verbose'], 
                                      capture_output=True, text=True)
                return 'Default: deny (incoming)' in result.stdout
            
            elif self.firewall_type == FirewallType.IPTABLES:
                result = subprocess.run(['iptables', '-L', 'INPUT'], 
                                      capture_output=True, text=True)
                return 'policy DROP' in result.stdout
            
            # Add checks for other firewall types
            return True
            
        except:
            return False
    
    def _check_logging_enabled(self) -> bool:
        """Check if firewall logging is enabled"""
        try:
            if self.firewall_type == FirewallType.UFW:
                result = subprocess.run(['ufw', 'status', 'verbose'], 
                                      capture_output=True, text=True)
                return 'Logging: on' in result.stdout
            
            # Add checks for other firewall types
            return True
            
        except:
            return False
    
    def _check_admin_access_restricted(self) -> bool:
        """Check if administrative access is properly restricted"""
        ssh_rules = [rule for rule in self.active_rules 
                    if rule.port == 22 and rule.action == RuleAction.ALLOW]
        
        for rule in ssh_rules:
            if rule.source in [None, "0.0.0.0/0", "::/0"]:
                return False  # SSH open to world
        
        return len(ssh_rules) > 0  # SSH access is configured but restricted
    
    def _check_network_segmentation(self) -> bool:
        """Check if network segmentation is implemented"""
        return len(self.zones) > 1  # Multiple zones indicate segmentation
    
    def _check_access_control(self) -> bool:
        """Check if proper access control is implemented"""
        return len(self.active_rules) > 3  # Assumes proper access control needs multiple rules
    
    def generate_compliance_report(self, framework: Optional[str] = None) -> str:
        """Generate comprehensive compliance report"""
        compliance_status = self._check_compliance()
        
        report = []
        report.append("ENTERPRISE FIREWALL COMPLIANCE REPORT")
        report.append("=" * 50)
        report.append(f"Generated: {time.ctime()}")
        report.append(f"Firewall Type: {self.firewall_type.value}")
        report.append("")
        
        if framework and framework in compliance_status:
            frameworks = [framework]
        else:
            frameworks = compliance_status.keys()
        
        for fw in frameworks:
            if fw in compliance_status:
                fw_status = compliance_status[fw]
                compliance_rate = (fw_status['score'] / fw_status['total'] * 100) if fw_status['total'] > 0 else 0
                
                report.append(f"{fw} COMPLIANCE:")
                report.append("-" * 20)
                report.append(f"Score: {fw_status['score']}/{fw_status['total']} ({compliance_rate:.1f}%)")
                report.append("")
                
                if fw_status['passed']:
                    report.append("PASSED CONTROLS:")
                    for control in fw_status['passed']:
                        report.append(f"  ✓ {control}")
                    report.append("")
                
                if fw_status['failed']:
                    report.append("FAILED CONTROLS:")
                    for control in fw_status['failed']:
                        report.append(f"  ✗ {control}")
                    report.append("")
        
        # Add policy summary
        report.append("SECURITY POLICIES:")
        report.append("-" * 20)
        for policy_name, policy in self.policies.items():
            report.append(f"  {policy_name}: {len(policy.rules)} rules")
            report.append(f"    Risk Level: {policy.risk_level}")
            report.append(f"    Environments: {', '.join(policy.environments)}")
        
        report.append("")
        report.append("NETWORK ZONES:")
        report.append("-" * 15)
        for zone_name, zone in self.zones.items():
            report.append(f"  {zone_name}: {zone.trust_level}")
            report.append(f"    Networks: {', '.join(zone.cidr_blocks)}")
        
        return "\n".join(report)
    
    def _log_security_event(self, event_type: str, message: str) -> None:
        """Log security events for SIEM integration"""
        event = {
            'timestamp': time.time(),
            'event_type': event_type,
            'message': message,
            'hostname': subprocess.run(['hostname'], capture_output=True, text=True).stdout.strip(),
            'firewall_type': self.firewall_type.value
        }
        
        # Log to security audit log
        self.logger.warning(f"SECURITY-EVENT: {event_type} - {message}")
        
        # Could send to SIEM here
        self._send_to_siem(event)
    
    def _send_to_siem(self, event: Dict[str, Any]) -> None:
        """Send security event to SIEM system"""
        # Placeholder for SIEM integration
        # In production, this would send to your SIEM system
        pass
    
    # Utility methods
    def _command_exists(self, command: str) -> bool:
        """Check if command exists"""
        result = subprocess.run(['which', command], capture_output=True)
        return result.returncode == 0
    
    def _install_package(self, package: str) -> None:
        """Install package using system package manager"""
        if self._is_debian_based():
            subprocess.run(['apt', 'update'], check=True)
            subprocess.run(['apt', 'install', '-y', package], check=True)
        else:
            subprocess.run(['dnf', 'install', '-y', package], check=True)
    
    def _is_debian_based(self) -> bool:
        """Check if system is Debian-based"""
        return Path('/etc/debian_version').exists()
    
    def _is_valid_network(self, network: str) -> bool:
        """Validate IP network"""
        try:
            ipaddress.ip_network(network, strict=False)
            return True
        except:
            return False
    
    def _is_valid_port(self, port: Union[int, str]) -> bool:
        """Validate port number"""
        try:
            port_num = int(port)
            return 1 <= port_num <= 65535
        except:
            return False
    
    def _is_ipv6_address(self, address: str) -> bool:
        """Check if address is IPv6"""
        try:
            ipaddress.IPv6Network(address, strict=False)
            return True
        except:
            return False

# Example usage and CLI interface
def main():
    import argparse
    
    parser = argparse.ArgumentParser(description='Enterprise Firewall Management System')
    parser.add_argument('action', choices=['status', 'apply', 'enable', 'report', 'init'],
                       help='Action to perform')
    parser.add_argument('--policy', help='Security policy name')
    parser.add_argument('--framework', choices=['CIS', 'NIST', 'PCI-DSS'], 
                       help='Compliance framework for report')
    parser.add_argument('--config', help='Configuration file path')
    
    args = parser.parse_args()
    
    # Initialize firewall manager
    config_file = args.config or "/etc/firewall/enterprise-config.yaml"
    fw_manager = EnterpriseFirewallManager(config_file)
    
    if args.action == 'init':
        print("Initializing enterprise firewall management...")
        fw_manager.save_configuration()
        print("Configuration saved. Apply policies with: --action apply --policy <policy_name>")
    
    elif args.action == 'status':
        status = fw_manager.get_firewall_status()
        print(f"Firewall Type: {status['firewall_type']}")
        print(f"Status: {'Enabled' if status['enabled'] else 'Disabled'}")
        print(f"Active Rules: {status['rule_count']}")
        print(f"Active Policies: {', '.join(status['active_policies'])}")
        
        if status['zones']:
            print(f"Network Zones: {', '.join(status['zones'])}")
    
    elif args.action == 'apply':
        if not args.policy:
            print("Error: --policy required for apply action")
            return 1
        
        if fw_manager.apply_security_policy(args.policy):
            print(f"Policy '{args.policy}' applied successfully")
        else:
            print(f"Failed to apply policy '{args.policy}'")
            return 1
    
    elif args.action == 'enable':
        if fw_manager.enable_firewall():
            print("Firewall enabled successfully")
        else:
            print("Failed to enable firewall")
            return 1
    
    elif args.action == 'report':
        report = fw_manager.generate_compliance_report(args.framework)
        print(report)
    
    return 0

if __name__ == '__main__':
    exit(main())

#!/bin/bash
# Enterprise Zero Trust Network Security Implementation

set -euo pipefail

# Configuration
ZERO_TRUST_CONFIG="/etc/firewall/zero-trust.conf"
POLICY_DIR="/etc/firewall/policies"
CERT_DIR="/etc/firewall/certs"
LOG_DIR="/var/log/zero-trust"

# Zero Trust principles
TRUST_LEVEL_VERIFIED="verified"
TRUST_LEVEL_UNVERIFIED="unverified"
TRUST_LEVEL_COMPROMISED="compromised"

# Network segments
declare -A NETWORK_SEGMENTS=(
    ["dmz"]="192.168.100.0/24"
    ["internal"]="10.0.0.0/8"
    ["mgmt"]="172.16.0.0/24"
    ["guest"]="192.168.200.0/24"
)

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
PURPLE='\033[0;35m'
NC='\033[0m'

# Logging
log() { echo -e "${BLUE}[$(date '+%Y-%m-%d %H:%M:%S')]${NC} $*" | tee -a "$LOG_DIR/zero-trust.log"; }
warn() { echo -e "${YELLOW}[WARN]${NC} $*" | tee -a "$LOG_DIR/zero-trust.log"; }
error() { echo -e "${RED}[ERROR]${NC} $*" | tee -a "$LOG_DIR/zero-trust.log"; }
success() { echo -e "${GREEN}[SUCCESS]${NC} $*" | tee -a "$LOG_DIR/zero-trust.log"; }
trust_event() { echo -e "${PURPLE}[TRUST]${NC} $*" | tee -a "$LOG_DIR/trust-events.log"; }

# Setup Zero Trust environment
setup_zero_trust_environment() {
    log "Setting up Zero Trust network security environment..."
    
    mkdir -p "$POLICY_DIR" "$CERT_DIR" "$LOG_DIR"
    chmod 700 "$CERT_DIR"
    chmod 755 "$POLICY_DIR" "$LOG_DIR"
    
    # Install required tools
    install_zero_trust_tools
    
    # Setup network segmentation
    setup_network_segmentation
    
    # Configure micro-segmentation
    configure_micro_segmentation
    
    # Setup identity verification
    setup_identity_verification
    
    success "Zero Trust environment setup completed"
}

# Install Zero Trust security tools
install_zero_trust_tools() {
    log "Installing Zero Trust security tools..."
    
    local tools=(
        "strongswan"      # IPsec VPN
        "wireguard"       # Modern VPN
        "openvpn"         # OpenVPN
        "nftables"        # Advanced firewall
        "iptables"        # Traditional firewall
        "fail2ban"        # Intrusion prevention
        "nginx"           # Reverse proxy
        "haproxy"         # Load balancer
        "openssl"         # SSL/TLS tools
    )
    
    if command -v apt >/dev/null 2>&1; then
        apt update
        for tool in "${tools[@]}"; do
            apt install -y "$tool" 2>/dev/null || warn "Failed to install $tool"
        done
    elif command -v yum >/dev/null 2>&1; then
        for tool in "${tools[@]}"; do
            yum install -y "$tool" 2>/dev/null || warn "Failed to install $tool"
        done
    fi
    
    success "Zero Trust tools installation completed"
}

# Setup network segmentation
setup_network_segmentation() {
    log "Configuring network segmentation..."
    
    # Create nftables configuration for segmentation
    cat > "/etc/nftables-zerotrust.conf" << 'EOF'
#!/usr/sbin/nft -f

# Zero Trust Network Segmentation Configuration
flush ruleset

table inet zerotrust {
    # Define network segments
    set dmz_networks {
        type ipv4_addr
        flags interval
        elements = { 192.168.100.0/24 }
    }
    
    set internal_networks {
        type ipv4_addr
        flags interval
        elements = { 10.0.0.0/8 }
    }
    
    set mgmt_networks {
        type ipv4_addr
        flags interval
        elements = { 172.16.0.0/24 }
    }
    
    set guest_networks {
        type ipv4_addr
        flags interval
        elements = { 192.168.200.0/24 }
    }
    
    # Trust levels
    set verified_hosts {
        type ipv4_addr
        flags interval
    }
    
    set compromised_hosts {
        type ipv4_addr
        flags interval
    }
    
    # Main chains
    chain input {
        type filter hook input priority 0; policy drop;
        
        # Allow loopback
        iif lo accept
        
        # Allow established connections
        ct state established,related accept
        
        # Allow ICMPv6
        ip6 nexthdr ipv6-icmp accept
        
        # Allow ICMP
        ip protocol icmp accept
        
        # Jump to trust verification
        jump trust_verification
        
        # Jump to segment rules
        jump segment_rules
        
        # Log and drop everything else
        log prefix "ZT-INPUT-DROP: " drop
    }
    
    chain forward {
        type filter hook forward priority 0; policy drop;
        
        # Allow established connections
        ct state established,related accept
        
        # Jump to inter-segment rules
        jump inter_segment_rules
        
        # Log and drop everything else
        log prefix "ZT-FORWARD-DROP: " drop
    }
    
    chain output {
        type filter hook output priority 0; policy accept;
    }
    
    # Trust verification chain
    chain trust_verification {
        # Block compromised hosts immediately
        ip saddr @compromised_hosts log prefix "ZT-COMPROMISED: " drop
        
        # Allow verified hosts with reduced restrictions
        ip saddr @verified_hosts jump verified_access
        
        # Unverified hosts get limited access
        jump unverified_access
    }
    
    # Verified host access
    chain verified_access {
        # Verified hosts get broader access
        ip saddr @internal_networks accept
        ip saddr @mgmt_networks accept
        return
    }
    
    # Unverified host access
    chain unverified_access {
        # Unverified hosts get very limited access
        tcp dport { 80, 443 } accept
        udp dport 53 accept
        return
    }
    
    # Segment-specific rules
    chain segment_rules {
        # DMZ access rules
        ip saddr @dmz_networks jump dmz_rules
        
        # Internal network rules
        ip saddr @internal_networks jump internal_rules
        
        # Management network rules
        ip saddr @mgmt_networks jump mgmt_rules
        
        # Guest network rules
        ip saddr @guest_networks jump guest_rules
    }
    
    # DMZ rules
    chain dmz_rules {
        # DMZ can access web services
        tcp dport { 80, 443 } accept
        tcp dport 53 accept
        udp dport 53 accept
        return
    }
    
    # Internal network rules
    chain internal_rules {
        # Internal networks get broader access
        tcp dport { 22, 80, 443, 993, 587 } accept
        udp dport { 53, 123 } accept
        return
    }
    
    # Management network rules
    chain mgmt_rules {
        # Management networks get admin access
        tcp dport { 22, 80, 443, 8080, 9090 } accept
        udp dport { 53, 123, 161 } accept
        return
    }
    
    # Guest network rules
    chain guest_rules {
        # Guests get very limited access
        tcp dport { 80, 443 } accept
        udp dport 53 accept
        return
    }
    
    # Inter-segment communication rules
    chain inter_segment_rules {
        # Block guest to internal
        ip saddr @guest_networks ip daddr @internal_networks log prefix "ZT-GUEST-TO-INTERNAL: " drop
        
        # Block guest to management
        ip saddr @guest_networks ip daddr @mgmt_networks log prefix "ZT-GUEST-TO-MGMT: " drop
        
        # Allow internal to DMZ (with restrictions)
        ip saddr @internal_networks ip daddr @dmz_networks tcp dport { 80, 443 } accept
        
        # Allow management to all (with logging)
        ip saddr @mgmt_networks log prefix "ZT-MGMT-ACCESS: " accept
        
        # Default deny with logging
        log prefix "ZT-INTER-SEGMENT-DENY: " drop
    }
}
EOF
    
    # Apply nftables configuration
    nft -f /etc/nftables-zerotrust.conf
    
    success "Network segmentation configured"
}

# Configure micro-segmentation
configure_micro_segmentation() {
    log "Configuring micro-segmentation policies..."
    
    # Create micro-segmentation rules for specific services
    cat > "$POLICY_DIR/microsegmentation.rules" << 'EOF'
# Micro-segmentation Rules
# Format: service:port:allowed_sources:trust_level_required

# Web services
web:80:dmz,internal:unverified
web:443:dmz,internal:unverified

# Database services
mysql:3306:internal:verified
postgresql:5432:internal:verified
redis:6379:internal:verified

# Administrative services
ssh:22:mgmt:verified
snmp:161:mgmt:verified
grafana:3000:mgmt:verified
prometheus:9090:mgmt:verified

# Application services
api:8080:internal,dmz:unverified
app:8443:internal:verified

# Email services
smtp:25:internal:verified
submission:587:internal:verified
imap:993:internal:verified
EOF
    
    # Generate nftables rules from micro-segmentation policy
    generate_microsegmentation_rules
    
    success "Micro-segmentation configured"
}

# Generate micro-segmentation rules
generate_microsegmentation_rules() {
    log "Generating micro-segmentation firewall rules..."
    
    local rules_file="/tmp/microseg-rules.nft"
    
    cat > "$rules_file" << 'EOF'
# Micro-segmentation rules
table inet microsegmentation {
    chain input {
        type filter hook input priority 1; policy accept;
        
EOF
    
    # Process micro-segmentation rules
    while IFS=':' read -r service port allowed_sources trust_level; do
        # Skip comments and empty lines
        [[ "$service" =~ ^#.*$ ]] && continue
        [[ -z "$service" ]] && continue
        
        log "Processing rule for service: $service on port $port"
        
        # Convert allowed sources to nftables format
        local source_conditions=""
        IFS=',' read -ra SOURCES <<< "$allowed_sources"
        
        for source in "${SOURCES[@]}"; do
            case "$source" in
                "dmz")
                    source_conditions+="ip saddr @dmz_networks "
                    ;;
                "internal")
                    source_conditions+="ip saddr @internal_networks "
                    ;;
                "mgmt")
                    source_conditions+="ip saddr @mgmt_networks "
                    ;;
                "guest")
                    source_conditions+="ip saddr @guest_networks "
                    ;;
            esac
        done
        
        # Add trust level requirement
        local trust_condition=""
        case "$trust_level" in
            "verified")
                trust_condition="ip saddr @verified_hosts"
                ;;
            "unverified")
                trust_condition=""  # No additional restriction
                ;;
        esac
        
        # Generate rule
        echo "        # Service: $service" >> "$rules_file"
        if [[ -n "$trust_condition" ]]; then
            echo "        $trust_condition $source_conditions tcp dport $port accept" >> "$rules_file"
        else
            echo "        $source_conditions tcp dport $port accept" >> "$rules_file"
        fi
        
    done < "$POLICY_DIR/microsegmentation.rules"
    
    cat >> "$rules_file" << 'EOF'
    }
}
EOF
    
    # Apply micro-segmentation rules
    nft -f "$rules_file"
    rm -f "$rules_file"
    
    success "Micro-segmentation rules applied"
}

# Setup identity verification
setup_identity_verification() {
    log "Setting up identity verification system..."
    
    # Create certificate authority for device certificates
    setup_certificate_authority
    
    # Configure device authentication
    configure_device_authentication
    
    # Setup continuous verification
    setup_continuous_verification
    
    success "Identity verification system configured"
}

# Setup certificate authority
setup_certificate_authority() {
    log "Setting up certificate authority..."
    
    local ca_dir="$CERT_DIR/ca"
    mkdir -p "$ca_dir"
    
    # Generate CA private key
    openssl genrsa -out "$ca_dir/ca-key.pem" 4096
    chmod 600 "$ca_dir/ca-key.pem"
    
    # Generate CA certificate
    openssl req -new -x509 -days 3650 -key "$ca_dir/ca-key.pem" \
        -out "$ca_dir/ca-cert.pem" \
        -subj "/C=US/ST=State/L=City/O=Enterprise/OU=Zero Trust/CN=Enterprise CA"
    
    # Create certificate database
    touch "$ca_dir/index.txt"
    echo "1000" > "$ca_dir/serial"
    
    # Create OpenSSL configuration
    cat > "$ca_dir/openssl.conf" << EOF
[ ca ]
default_ca = CA_default

[ CA_default ]
dir               = $ca_dir
certs             = \$dir/certs
crl_dir           = \$dir/crl
new_certs_dir     = \$dir/newcerts
database          = \$dir/index.txt
serial            = \$dir/serial
RANDFILE          = \$dir/private/.rand

private_key       = \$dir/ca-key.pem
certificate       = \$dir/ca-cert.pem

crlnumber         = \$dir/crlnumber
crl               = \$dir/crl.pem
crl_extensions    = crl_ext

default_days      = 365
default_crl_days  = 30
default_md        = sha256

name_opt          = ca_default
cert_opt          = ca_default

policy            = policy_strict

[ policy_strict ]
countryName             = match
stateOrProvinceName     = match
organizationName        = match
organizationalUnitName  = optional
commonName              = supplied
emailAddress            = optional

[ req ]
default_bits        = 2048
distinguished_name  = req_distinguished_name
string_mask         = utf8only
default_md          = sha256

[ req_distinguished_name ]
countryName                     = Country Name (2 letter code)
stateOrProvinceName             = State or Province Name
localityName                    = Locality Name
0.organizationName              = Organization Name
organizationalUnitName          = Organizational Unit Name
commonName                      = Common Name
emailAddress                    = Email Address
EOF

    success "Certificate authority setup completed"
}

# Configure device authentication
configure_device_authentication() {
    log "Configuring device authentication..."
    
    # Create device verification script
    cat > "/usr/local/bin/verify-device.sh" << 'EOF'
#!/bin/bash
# Device Verification Script for Zero Trust

DEVICE_IP="$1"
CERT_FILE="$2"
CA_CERT="/etc/firewall/certs/ca/ca-cert.pem"
VERIFIED_HOSTS_SET="verified_hosts"
COMPROMISED_HOSTS_SET="compromised_hosts"

verify_device_certificate() {
    local device_ip="$1"
    local cert_file="$2"
    
    # Verify certificate against CA
    if openssl verify -CAfile "$CA_CERT" "$cert_file" >/dev/null 2>&1; then
        echo "Certificate verification passed for $device_ip"
        return 0
    else
        echo "Certificate verification failed for $device_ip"
        return 1
    fi
}

add_to_verified_hosts() {
    local device_ip="$1"
    
    # Add to nftables verified hosts set
    nft add element inet zerotrust verified_hosts { "$device_ip" }
    
    # Log trust event
    logger -p security.info "ZERO-TRUST: Device $device_ip verified and added to trusted set"
}

remove_from_verified_hosts() {
    local device_ip="$1"
    
    # Remove from nftables verified hosts set
    nft delete element inet zerotrust verified_hosts { "$device_ip" } 2>/dev/null || true
    
    # Log trust event
    logger -p security.warn "ZERO-TRUST: Device $device_ip removed from trusted set"
}

mark_as_compromised() {
    local device_ip="$1"
    
    # Remove from verified hosts
    remove_from_verified_hosts "$device_ip"
    
    # Add to compromised hosts
    nft add element inet zerotrust compromised_hosts { "$device_ip" }
    
    # Log security event
    logger -p security.crit "ZERO-TRUST: Device $device_ip marked as compromised"
}

# Main verification logic
if [[ -z "$DEVICE_IP" || -z "$CERT_FILE" ]]; then
    echo "Usage: $0 <device_ip> <cert_file>"
    exit 1
fi

if verify_device_certificate "$DEVICE_IP" "$CERT_FILE"; then
    add_to_verified_hosts "$DEVICE_IP"
    exit 0
else
    remove_from_verified_hosts "$DEVICE_IP"
    exit 1
fi
EOF

    chmod +x "/usr/local/bin/verify-device.sh"
    
    success "Device authentication configured"
}

# Setup continuous verification
setup_continuous_verification() {
    log "Setting up continuous verification system..."
    
    # Create continuous verification script
    cat > "/usr/local/bin/continuous-verification.sh" << 'EOF'
#!/bin/bash
# Continuous Zero Trust Verification

LOG_FILE="/var/log/zero-trust/continuous-verification.log"
VERIFICATION_INTERVAL=300  # 5 minutes

log_message() {
    echo "$(date '+%Y-%m-%d %H:%M:%S') - $*" >> "$LOG_FILE"
}

verify_trust_levels() {
    local verified_count=0
    local compromised_count=0
    
    # Get current verified hosts
    local verified_hosts=$(nft list set inet zerotrust verified_hosts 2>/dev/null | grep "elements" | cut -d'{' -f2 | cut -d'}' -f1)
    
    for host in $verified_hosts; do
        # Remove quotes and commas
        host=$(echo "$host" | tr -d '", ')
        [[ -z "$host" ]] && continue
        
        # Check if host is still responding appropriately
        if ! check_host_behavior "$host"; then
            log_message "Host $host failed behavioral check - removing from verified set"
            nft delete element inet zerotrust verified_hosts { "$host" } 2>/dev/null || true
        else
            ((verified_count++))
        fi
    done
    
    # Get compromised hosts count
    local compromised_hosts=$(nft list set inet zerotrust compromised_hosts 2>/dev/null | grep "elements" | cut -d'{' -f2 | cut -d'}' -f1)
    for host in $compromised_hosts; do
        host=$(echo "$host" | tr -d '", ')
        [[ -z "$host" ]] && continue
        ((compromised_count++))
    done
    
    log_message "Verification complete: $verified_count verified hosts, $compromised_count compromised hosts"
}

check_host_behavior() {
    local host="$1"
    
    # Simple behavioral check - ping and port scan detection
    if ping -c 1 -W 1 "$host" >/dev/null 2>&1; then
        # Check for suspicious activity (simplified)
        local recent_connections=$(netstat -an | grep "$host" | wc -l)
        
        # If host has too many connections, might be suspicious
        if [[ $recent_connections -gt 100 ]]; then
            return 1
        fi
        
        return 0
    else
        # Host not responding
        return 1
    fi
}

# Main verification loop
while true; do
    verify_trust_levels
    sleep "$VERIFICATION_INTERVAL"
done
EOF

    chmod +x "/usr/local/bin/continuous-verification.sh"
    
    # Create systemd service for continuous verification
    cat > "/etc/systemd/system/zero-trust-verification.service" << EOF
[Unit]
Description=Zero Trust Continuous Verification
After=network.target
Wants=network.target

[Service]
Type=simple
ExecStart=/usr/local/bin/continuous-verification.sh
Restart=always
RestartSec=10
User=root

[Install]
WantedBy=multi-user.target
EOF

    systemctl daemon-reload
    systemctl enable zero-trust-verification.service
    
    success "Continuous verification system configured"
}

# Implement Zero Trust policies
implement_zero_trust_policies() {
    log "Implementing Zero Trust security policies..."
    
    # Apply default deny all policy
    apply_default_deny_policy
    
    # Implement least privilege access
    implement_least_privilege
    
    # Setup monitoring and alerting
    setup_zero_trust_monitoring
    
    success "Zero Trust policies implemented"
}

# Apply default deny policy
apply_default_deny_policy() {
    log "Applying default deny policy..."
    
    # Ensure nftables configuration has proper default policies
    nft add table inet zerotrust 2>/dev/null || true
    nft add chain inet zerotrust input { type filter hook input priority 0\; policy drop\; } 2>/dev/null || true
    nft add chain inet zerotrust forward { type filter hook forward priority 0\; policy drop\; } 2>/dev/null || true
    
    success "Default deny policy applied"
}

# Implement least privilege access
implement_least_privilege() {
    log "Implementing least privilege access controls..."
    
    # Create service-specific access controls
    local services=(
        "ssh:22:mgmt"
        "http:80:dmz,internal"
        "https:443:dmz,internal"
        "dns:53:all"
    )
    
    for service_def in "${services[@]}"; do
        IFS=':' read -r service port networks <<< "$service_def"
        
        log "Configuring least privilege for $service on port $port"
        
        # Add specific rules based on service requirements
        case "$networks" in
            "mgmt")
                nft add rule inet zerotrust input ip saddr @mgmt_networks tcp dport "$port" accept 2>/dev/null || true
                ;;
            "dmz,internal")
                nft add rule inet zerotrust input ip saddr @dmz_networks tcp dport "$port" accept 2>/dev/null || true
                nft add rule inet zerotrust input ip saddr @internal_networks tcp dport "$port" accept 2>/dev/null || true
                ;;
            "all")
                nft add rule inet zerotrust input tcp dport "$port" accept 2>/dev/null || true
                nft add rule inet zerotrust input udp dport "$port" accept 2>/dev/null || true
                ;;
        esac
    done
    
    success "Least privilege access implemented"
}

# Setup Zero Trust monitoring
setup_zero_trust_monitoring() {
    log "Setting up Zero Trust monitoring..."
    
    # Create monitoring script
    cat > "/usr/local/bin/zero-trust-monitor.sh" << 'EOF'
#!/bin/bash
# Zero Trust Security Monitoring

METRICS_FILE="/var/log/zero-trust/metrics.log"
ALERT_THRESHOLD_FAILED_VERIFICATIONS=5
ALERT_THRESHOLD_COMPROMISED_HOSTS=3

log_metric() {
    echo "$(date '+%Y-%m-%d %H:%M:%S'),$*" >> "$METRICS_FILE"
}

check_trust_metrics() {
    # Get verification statistics
    local verified_hosts=$(nft list set inet zerotrust verified_hosts 2>/dev/null | grep -o '{[^}]*}' | tr -d '{},' | wc -w)
    local compromised_hosts=$(nft list set inet zerotrust compromised_hosts 2>/dev/null | grep -o '{[^}]*}' | tr -d '{},' | wc -w)
    
    # Get failed verification attempts from logs
    local failed_verifications=$(grep "Certificate verification failed" /var/log/zero-trust/continuous-verification.log 2>/dev/null | grep "$(date '+%Y-%m-%d')" | wc -l)
    
    # Log metrics
    log_metric "verified_hosts,$verified_hosts"
    log_metric "compromised_hosts,$compromised_hosts"
    log_metric "failed_verifications,$failed_verifications"
    
    # Check alert thresholds
    if [[ $failed_verifications -gt $ALERT_THRESHOLD_FAILED_VERIFICATIONS ]]; then
        logger -p security.warn "ZERO-TRUST-ALERT: High number of failed verifications: $failed_verifications"
    fi
    
    if [[ $compromised_hosts -gt $ALERT_THRESHOLD_COMPROMISED_HOSTS ]]; then
        logger -p security.crit "ZERO-TRUST-ALERT: High number of compromised hosts: $compromised_hosts"
    fi
    
    # Output current status
    echo "VERIFIED_HOSTS,$verified_hosts"
    echo "COMPROMISED_HOSTS,$compromised_hosts"
    echo "FAILED_VERIFICATIONS,$failed_verifications"
}

check_segment_violations() {
    # Check for inter-segment violations in logs
    local segment_violations=$(grep "ZT-INTER-SEGMENT-DENY" /var/log/kern.log 2>/dev/null | grep "$(date '+%b %d')" | wc -l)
    
    log_metric "segment_violations,$segment_violations"
    echo "SEGMENT_VIOLATIONS,$segment_violations"
    
    if [[ $segment_violations -gt 10 ]]; then
        logger -p security.warn "ZERO-TRUST-ALERT: High number of segment violations: $segment_violations"
    fi
}

# Main monitoring execution
check_trust_metrics
check_segment_violations
EOF

    chmod +x "/usr/local/bin/zero-trust-monitor.sh"
    
    # Create monitoring timer
    cat > "/etc/systemd/system/zero-trust-monitor.service" << EOF
[Unit]
Description=Zero Trust Security Monitoring
After=network.target

[Service]
Type=oneshot
ExecStart=/usr/local/bin/zero-trust-monitor.sh
User=root
StandardOutput=journal
StandardError=journal
EOF

    cat > "/etc/systemd/system/zero-trust-monitor.timer" << EOF
[Unit]
Description=Run Zero Trust monitoring every 5 minutes
Requires=zero-trust-monitor.service

[Timer]
OnCalendar=*:*/5:00
Persistent=true

[Install]
WantedBy=timers.target
EOF

    systemctl daemon-reload
    systemctl enable zero-trust-monitor.timer
    systemctl start zero-trust-monitor.timer
    
    success "Zero Trust monitoring configured"
}

# Generate Zero Trust status report
generate_zero_trust_report() {
    local report_file="$LOG_DIR/zero_trust_report_$(date +%Y%m%d_%H%M%S).txt"
    
    log "Generating Zero Trust status report..."
    
    {
        echo "ZERO TRUST NETWORK SECURITY REPORT"
        echo "=================================="
        echo "Generated: $(date)"
        echo "Hostname: $(hostname)"
        echo ""
        
        echo "NETWORK SEGMENTATION:"
        echo "===================="
        for segment in "${!NETWORK_SEGMENTS[@]}"; do
            echo "  $segment: ${NETWORK_SEGMENTS[$segment]}"
        done
        echo ""
        
        echo "TRUST LEVELS:"
        echo "============"
        local verified_hosts=$(nft list set inet zerotrust verified_hosts 2>/dev/null | grep -o '{[^}]*}' | tr -d '{},' | wc -w)
        local compromised_hosts=$(nft list set inet zerotrust compromised_hosts 2>/dev/null | grep -o '{[^}]*}' | tr -d '{},' | wc -w)
        
        echo "  Verified Hosts: $verified_hosts"
        echo "  Compromised Hosts: $compromised_hosts"
        echo ""
        
        echo "RECENT TRUST EVENTS:"
        echo "==================="
        tail -20 "$LOG_DIR/trust-events.log" 2>/dev/null || echo "No recent trust events"
        echo ""
        
        echo "FIREWALL RULES:"
        echo "=============="
        nft list table inet zerotrust 2>/dev/null | head -50
        echo ""
        
        echo "SECURITY METRICS:"
        echo "================"
        if [[ -f "$LOG_DIR/metrics.log" ]]; then
            tail -10 "$LOG_DIR/metrics.log"
        else
            echo "No metrics available"
        fi
        
    } > "$report_file"
    
    cat "$report_file"
    success "Zero Trust report generated: $report_file"
}

# Main execution
main() {
    case "${1:-help}" in
        "setup")
            setup_zero_trust_environment
            implement_zero_trust_policies
            ;;
        "start")
            systemctl start zero-trust-verification.service
            systemctl start zero-trust-monitor.timer
            success "Zero Trust services started"
            ;;
        "stop")
            systemctl stop zero-trust-verification.service
            systemctl stop zero-trust-monitor.timer
            success "Zero Trust services stopped"
            ;;
        "status")
            /usr/local/bin/zero-trust-monitor.sh
            ;;
        "report")
            generate_zero_trust_report
            ;;
        "verify")
            if [[ -n "${2:-}" && -n "${3:-}" ]]; then
                /usr/local/bin/verify-device.sh "$2" "$3"
            else
                echo "Usage: $0 verify <device_ip> <cert_file>"
            fi
            ;;
        *)
            echo "Usage: $0 {setup|start|stop|status|report|verify}"
            echo ""
            echo "Commands:"
            echo "  setup   - Setup Zero Trust environment"
            echo "  start   - Start Zero Trust services"
            echo "  stop    - Stop Zero Trust services"
            echo "  status  - Show current status"
            echo "  report  - Generate status report"
            echo "  verify  - Verify device certificate"
            exit 1
            ;;
    esac
}

# Check for root privileges
if [[ $EUID -ne 0 ]]; then
    error "This script must be run as root"
    exit 1
fi

main "$@"