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🔥 NeXuS PARANOID SECURITY ARCHITECTURE 🔥

Sane • Simple • Secure • Stealthy • Beautiful

Together Everyone Achieves More - Through Absolute Anonymity

🎯 MISSION: PARANOID-LEVEL SECURITY

"Assume everything is compromised. Design for survival when adversaries control the network."

This document establishes military-grade security verification for the NeXuS routing stack, defending against state-level adversaries, mass surveillance, and advanced persistent threats.

🛡️ THREAT MODEL: STATE-LEVEL ADVERSARIES

Primary Adversaries

  • Five Eyes Intelligence Agencies (NSA, GCHQ, CSEC, ASD, GCSB)
  • Nation-State Actors (APT groups, cyber warfare units)
  • ISP Mass Surveillance (Deep packet inspection, traffic correlation)
  • Corporate Data Harvesting (Google, Meta, Amazon tracking)
  • Local Network Attackers (Evil twin APs, MITM attacks)

Attack Vectors We Defend Against

Network-Level Attacks

  • Traffic Correlation Attacks - Timing analysis across entry/exit nodes
  • DNS Leaks - Real DNS queries revealing browsing activity
  • IPv6 Leaks - IPv6 traffic bypassing IPv4 Tor routing
  • WebRTC Leaks - Browser WebRTC exposing real IP addresses
  • STUN/TURN Leaks - P2P protocols revealing internal IPs

Protocol-Level Attacks

  • SSL/TLS Interception - MITM with compromised root certificates
  • DNS over HTTPS (DoH) Bypass - Hardcoded DoH servers leaking queries
  • NTP Time Correlation - Clock skew analysis for identity correlation
  • TCP Timestamp Fingerprinting - OS identification via TCP options
  • HTTP Header Fingerprinting - User agent and browser uniqueness

System-Level Attacks

  • DNS Cache Poisoning - Malicious DNS responses cached locally
  • Local Network Discovery - LAN scanning revealing network topology
  • Tor Browser Exploits - Zero-day exploits targeting Tor Browser Bundle
  • Container Escape - Breaking out of containerized anonymity networks
  • Kernel-Level Rootkits - Persistent malware surviving reboots

Side-Channel Attacks

  • Timing Attacks - Response time analysis revealing user behavior
  • Packet Size Analysis - Traffic patterns identifying specific protocols
  • Keystroke Timing - Typing patterns for user identification
  • Memory Dumps - RAM analysis revealing encryption keys
  • Power Analysis - Electromagnetic emanations from hardware

🔒 DEFENSE-IN-DEPTH ARCHITECTURE

Layer 1: Container Isolation (Last Line of Defense)

Layer 2: Network Anonymization (Tor, I2P, Yggdrasil)

Layer 3: Leak Prevention (DNS, IPv6, WebRTC blocking)

Layer 4: Traffic Obfuscation (Timing, padding, cover traffic)

Layer 5: Kill Switch (Emergency circuit breaker)

Layer 6: Continuous Verification (Real-time leak detection)

🚨 LAYER 1: CONTAINER SECURITY FORTRESS

Paranoid Container Hardening Profile

# /home/user/claude/configs/nexus-stack/configs/container-security-profile.yml
# NeXuS Container Security Baseline - PARANOID MODE

name: "nexus-paranoid-baseline"
version: "1.0"
threat_model: "state-level-adversary"

security_controls:
  # Namespace Isolation - Maximum Separation
  namespaces:
    - pid: true          # Isolated process tree
    - network: true      # Isolated network stack
    - ipc: true          # Isolated shared memory
    - uts: true          # Isolated hostname
    - user: true         # Isolated user namespaces
    - cgroup: true       # Isolated resource controls
    - mount: true        # Isolated filesystem mounts

  # Capability Dropping - Minimum Privileges
  capabilities:
    drop_all: true
    whitelist:
      - CAP_NET_BIND_SERVICE  # Only for binding ports <1024
      - CAP_NET_RAW           # Only for raw socket access (ping)
    blacklist:
      - CAP_SYS_ADMIN         # NEVER allow system administration
      - CAP_SYS_MODULE        # NEVER allow kernel module loading
      - CAP_SYS_RAWIO         # NEVER allow raw I/O access
      - CAP_SYS_PTRACE        # NEVER allow process tracing
      - CAP_DAC_OVERRIDE      # NEVER allow permission bypassing
      - CAP_SETUID            # NEVER allow UID changes
      - CAP_SETGID            # NEVER allow GID changes

  # Seccomp Profiles - System Call Filtering
  seccomp:
    mode: "strict"
    profile: "/etc/nexus/seccomp/paranoid.json"
    deny_list:
      # Block all dangerous syscalls
      - ptrace              # Process inspection/debugging
      - process_vm_readv    # Reading other process memory
      - process_vm_writev   # Writing other process memory
      - perf_event_open     # Performance monitoring (timing attacks)
      - personality         # Execution domain changes
      - mount               # Filesystem mounting
      - umount              # Filesystem unmounting
      - pivot_root          # Root filesystem changes
      - kexec_load          # Kernel execution
      - reboot              # System reboot
      - swapon              # Swap management
      - swapoff             # Swap management
      - setns               # Namespace manipulation
      - unshare             # Resource unsharing

  # AppArmor/SELinux Policies - Mandatory Access Control
  mandatory_access_control:
    engine: "apparmor"  # or "selinux" depending on distribution
    profile: "/etc/apparmor.d/nexus-container"
    rules:
      filesystem:
        - deny_write: "/proc/**"
        - deny_write: "/sys/**"
        - deny_read: "/proc/sys/kernel/**"
        - allow_read: "/proc/self/**"
      network:
        - deny_raw_sockets: true
        - allow_ipv4: true
        - deny_ipv6: true  # Blocked by default, only whitelist
      capabilities:
        - deny_all_capabilities: true

  # Read-Only Root Filesystem - Prevent Persistence
  filesystem:
    read_only_root: true
    writable_paths:
      - /tmp                     # Temporary files (tmpfs)
      - /var/tmp                 # Temporary files (tmpfs)
      - /var/log                 # Logs (bind mount to host)
      - /var/run                 # Runtime data (tmpfs)
      - /home/user/.config       # Configuration (bind mount)
    tmpfs_mounts:
      - path: /tmp
        size: "256M"
        mode: "1777"
        options: "noexec,nosuid,nodev"
      - path: /var/tmp
        size: "256M"
        mode: "1777"
        options: "noexec,nosuid,nodev"
      - path: /run
        size: "128M"
        mode: "0755"
        options: "noexec,nosuid,nodev"

  # No New Privileges - Prevent Privilege Escalation
  security_options:
    - "no-new-privileges:true"
    - "seccomp=unconfined"  # Our custom seccomp profile is stricter

  # Resource Limits - Prevent DoS
  resource_limits:
    cpu:
      shares: 512           # CPU priority (max 1024)
      period: 100000        # CPU period (microseconds)
      quota: 50000          # CPU quota (50% of one core)
    memory:
      limit: "512M"         # Hard memory limit
      reservation: "128M"   # Memory reservation
      swap: "0"             # No swap (prevent memory inspection)
    pids:
      limit: 256            # Maximum processes
    files:
      soft_limit: 1024      # File descriptor soft limit
      hard_limit: 2048      # File descriptor hard limit

  # Network Security - Isolated Networks Only
  network:
    driver: "bridge"
    internal: true          # No external connectivity by default
    enable_ipv6: false      # IPv6 disabled globally
    icc: false              # Inter-container communication disabled
    dns:
      servers: []           # No DNS servers (use Tor DNS)
      search: []            # No DNS search domains
      options: []           # No DNS options

  # Logging and Auditing - Full Visibility
  logging:
    driver: "json-file"
    options:
      max_size: "10m"
      max_file: "3"
      labels: "nexus.component,nexus.network"
      env: "NEXUS_NODE_ID,NEXUS_NETWORK"

  # Health Checks - Continuous Monitoring
  health_check:
    test: ["CMD-SHELL", "curl -sf http://127.0.0.1:9050 || exit 1"]
    interval: "30s"
    timeout: "10s"
    retries: 3
    start_period: "60s"

# Emergency Kill Switch Integration
kill_switch:
  enabled: true
  triggers:
    - leak_detected
    - anonymity_failure
    - container_escape_attempt
    - suspicious_syscall_pattern
  action:
    - stop_all_containers
    - flush_iptables
    - clear_dns_cache
    - wipe_temp_files
    - alert_user

Seccomp Profile (Paranoid Mode)

{
  "defaultAction": "SCMP_ACT_ERRNO",
  "defaultErrnoRet": 1,
  "archMap": [
    {
      "architecture": "SCMP_ARCH_X86_64",
      "subArchitectures": ["SCMP_ARCH_X86", "SCMP_ARCH_X32"]
    }
  ],
  "syscalls": [
    {
      "names": [
        "read", "write", "open", "close", "stat", "fstat", "lstat", "poll",
        "lseek", "mmap", "mprotect", "munmap", "brk", "rt_sigaction",
        "rt_sigprocmask", "rt_sigreturn", "ioctl", "pread64", "pwrite64",
        "readv", "writev", "access", "pipe", "select", "sched_yield",
        "mremap", "msync", "mincore", "madvise", "socket", "connect",
        "accept", "sendto", "recvfrom", "sendmsg", "recvmsg", "shutdown",
        "bind", "listen", "getsockname", "getpeername", "socketpair",
        "setsockopt", "getsockopt", "clone", "fork", "vfork", "execve",
        "exit", "wait4", "kill", "uname", "fcntl", "flock", "fsync",
        "truncate", "ftruncate", "getdents", "getcwd", "chdir", "fchdir",
        "rename", "mkdir", "rmdir", "creat", "link", "unlink", "symlink",
        "readlink", "chmod", "fchmod", "chown", "fchown", "lchown",
        "umask", "gettimeofday", "getrlimit", "getrusage", "sysinfo",
        "times", "getpid", "getppid", "getuid", "geteuid", "getgid",
        "getegid", "setpgid", "getpgrp", "setsid", "getgroups",
        "setgroups", "rt_sigpending", "rt_sigtimedwait", "rt_sigqueueinfo",
        "rt_sigsuspend", "sigaltstack", "utime", "mknod", "statfs",
        "fstatfs", "getpriority", "setpriority", "sched_setparam",
        "sched_getparam", "sched_setscheduler", "sched_getscheduler",
        "sched_get_priority_max", "sched_get_priority_min", "mlock",
        "munlock", "mlockall", "munlockall", "prctl", "arch_prctl",
        "setrlimit", "sync", "gettid", "futex", "sched_setaffinity",
        "sched_getaffinity", "set_tid_address", "epoll_create",
        "epoll_ctl", "epoll_wait", "epoll_pwait", "clock_gettime",
        "clock_getres", "clock_nanosleep", "exit_group", "tgkill",
        "openat", "mkdirat", "fchownat", "newfstatat", "unlinkat",
        "renameat", "linkat", "symlinkat", "readlinkat", "fchmodat",
        "faccessat", "pselect6", "ppoll", "unshare", "set_robust_list",
        "get_robust_list", "splice", "tee", "sync_file_range",
        "utimensat", "epoll_pwait", "signalfd", "timerfd_create",
        "eventfd", "fallocate", "timerfd_settime", "timerfd_gettime",
        "accept4", "signalfd4", "eventfd2", "epoll_create1", "dup3",
        "pipe2", "inotify_init1", "preadv", "pwritev", "recvmmsg",
        "fanotify_init", "fanotify_mark", "name_to_handle_at",
        "open_by_handle_at", "syncfs", "sendmmsg", "getcpu"
      ],
      "action": "SCMP_ACT_ALLOW"
    },
    {
      "names": [
        "ptrace", "process_vm_readv", "process_vm_writev",
        "perf_event_open", "personality", "mount", "umount", "umount2",
        "pivot_root", "kexec_load", "kexec_file_load", "reboot",
        "swapon", "swapoff", "acct", "settimeofday", "stime", "adjtimex",
        "clock_settime", "init_module", "finit_module", "delete_module",
        "lookup_dcookie", "quotactl", "request_key", "keyctl", "ioperm",
        "iopl", "create_module", "get_kernel_syms", "query_module",
        "uselib", "_sysctl", "sysfs", "vm86", "vm86old", "vserver",
        "bpf", "userfaultfd", "copy_file_range"
      ],
      "action": "SCMP_ACT_ERRNO",
      "errnoRet": 1
    }
  ]
}

AppArmor Profile

# /etc/apparmor.d/nexus-container
# NeXuS Container AppArmor Profile - PARANOID MODE

#include <tunables/global>

profile nexus-container flags=(attach_disconnected,mediate_deleted) {
  #include <abstractions/base>

  # Deny everything by default
  deny /** rwklx,

  # Allow reading essential system files
  /etc/hosts r,
  /etc/hostname r,
  /etc/resolv.conf r,
  /etc/nsswitch.conf r,
  /etc/passwd r,
  /etc/group r,

  # Allow reading application files (read-only)
  /usr/** r,
  /lib/** r,
  /lib64/** r,

  # Allow writing to specific writable directories
  /tmp/** rw,
  /var/tmp/** rw,
  /var/run/** rw,
  /var/log/** w,

  # Allow reading process information
  /proc/self/** r,
  /proc/sys/kernel/hostname r,
  /proc/sys/kernel/ostype r,
  /proc/sys/kernel/osrelease r,

  # Deny dangerous proc/sys access
  deny /proc/sys/kernel/** rw,
  deny /proc/sys/net/** rw,
  deny /proc/kcore r,
  deny /proc/kmem r,
  deny /proc/mem r,

  # Deny all sys access (hardware manipulation)
  deny /sys/** rwklx,

  # Network access (limited)
  network inet stream,
  network inet dgram,

  # Deny IPv6 (potential leak vector)
  deny network inet6,

  # Deny raw sockets (prevent packet crafting)
  deny network raw,
  deny network packet,

  # Deny all capabilities by default
  deny capability,

  # Allow only essential capabilities
  capability net_bind_service,
  capability net_raw,

  # Ptrace restrictions (prevent debugging)
  deny ptrace,
  deny signal,

  # Mount restrictions (prevent container escape)
  deny mount,
  deny remount,
  deny umount,
  deny pivot_root,

  # Unix sockets (for IPC)
  unix (send, receive) type=stream,
  unix (send, receive) type=dgram,
}

🚫 LAYER 2: COMPREHENSIVE LEAK PREVENTION

DNS Leak Prevention System

#!/bin/bash
# /home/user/scripts/nexus-dns-leak-prevention.sh
# NeXuS DNS Leak Prevention - PARANOID MODE

set -euo pipefail

SCRIPT_NAME="nexus-dns-leak-prevention"
LOG_FILE="/var/log/nexus-security/${SCRIPT_NAME}.log"
CONFIG_DIR="/home/user/.config/nexus"

log() {
    echo "[$(date +'%Y-%m-%d %H:%M:%S')] $*" | tee -a "$LOG_FILE"
}

# 1. DISABLE ALL SYSTEM DNS RESOLVERS
disable_system_dns() {
    log "🚫 Disabling system DNS resolvers..."

    # Disable systemd-resolved (Ubuntu/Debian)
    if systemctl is-active --quiet systemd-resolved 2>/dev/null; then
        sudo systemctl stop systemd-resolved
        sudo systemctl disable systemd-resolved
        log "✅ Disabled systemd-resolved"
    fi

    # Backup and replace resolv.conf
    if [[ -f /etc/resolv.conf ]]; then
        sudo cp /etc/resolv.conf /etc/resolv.conf.backup
        sudo rm -f /etc/resolv.conf
    fi

    # Create locked resolv.conf (no external DNS)
    sudo tee /etc/resolv.conf > /dev/null <<EOF
# NeXuS DNS Leak Prevention - All DNS goes through Tor
# DO NOT MODIFY - This file is managed by nexus-dns-leak-prevention
nameserver 127.0.0.1
EOF

    # Make immutable (prevent modifications)
    sudo chattr +i /etc/resolv.conf
    log "✅ Locked /etc/resolv.conf to localhost only"
}

# 2. CONFIGURE TOR DNS (DNSPort 53)
configure_tor_dns() {
    log "🧅 Configuring Tor DNS on port 53..."

    # Tor configuration for DNS
    cat > "$CONFIG_DIR/tor/torrc.dns" <<EOF
# NeXuS Tor DNS Configuration - PARANOID MODE
# All DNS queries go through Tor

# DNS Port (requires root or CAP_NET_BIND_SERVICE)
DNSPort 127.0.0.1:53
DNSPort [::1]:53

# Automatic mapping of .onion domains
AutomapHostsOnResolve 1
AutomapHostsSuffixes .onion,.exit

# Virtual address network for .onion
VirtualAddrNetworkIPv4 10.192.0.0/10
VirtualAddrNetworkIPv6 [FC00::]/7

# DNS cache (prevent repeated queries)
DNSCache 1
DNSCacheMaxSize 4096

# DNS timeout
DNSQueryTimeout 30

# Reject non-Tor DNS queries
DNSRejectInternalAddresses 1

# Use DNSSEC when possible
DNSSEC 1

# Enforce DNS over Tor
EnforceDistinctSubnets 1
EOF

    log "✅ Tor DNS configuration created"
}

# 3. BLOCK ALL NON-TOR DNS WITH IPTABLES
block_external_dns() {
    log "🔥 Blocking all external DNS traffic..."

    # Flush existing DNS rules
    sudo iptables -F DNS_LEAK_PREVENTION 2>/dev/null || true
    sudo iptables -X DNS_LEAK_PREVENTION 2>/dev/null || true

    # Create DNS leak prevention chain
    sudo iptables -N DNS_LEAK_PREVENTION

    # ALLOW: Loopback DNS (Tor DNS on 127.0.0.1:53)
    sudo iptables -A DNS_LEAK_PREVENTION -d 127.0.0.0/8 -p udp --dport 53 -j ACCEPT
    sudo iptables -A DNS_LEAK_PREVENTION -d 127.0.0.0/8 -p tcp --dport 53 -j ACCEPT

    # BLOCK: All other DNS queries (external DNS servers)
    sudo iptables -A DNS_LEAK_PREVENTION -p udp --dport 53 -j DROP
    sudo iptables -A DNS_LEAK_PREVENTION -p tcp --dport 53 -j DROP

    # BLOCK: DNS over HTTPS (DoH) on port 443 to known DoH providers
    # Google DoH
    sudo iptables -A DNS_LEAK_PREVENTION -d 8.8.8.8 -p tcp --dport 443 -j DROP
    sudo iptables -A DNS_LEAK_PREVENTION -d 8.8.4.4 -p tcp --dport 443 -j DROP
    # Cloudflare DoH
    sudo iptables -A DNS_LEAK_PREVENTION -d 1.1.1.1 -p tcp --dport 443 -j DROP
    sudo iptables -A DNS_LEAK_PREVENTION -d 1.0.0.1 -p tcp --dport 443 -j DROP
    # Quad9 DoH
    sudo iptables -A DNS_LEAK_PREVENTION -d 9.9.9.9 -p tcp --dport 443 -j DROP
    sudo iptables -A DNS_LEAK_PREVENTION -d 149.112.112.112 -p tcp --dport 443 -j DROP

    # Insert into OUTPUT chain
    sudo iptables -I OUTPUT 1 -j DNS_LEAK_PREVENTION

    # Same for IPv6
    sudo ip6tables -F DNS_LEAK_PREVENTION 2>/dev/null || true
    sudo ip6tables -X DNS_LEAK_PREVENTION 2>/dev/null || true
    sudo ip6tables -N DNS_LEAK_PREVENTION
    sudo ip6tables -A DNS_LEAK_PREVENTION -d ::1/128 -p udp --dport 53 -j ACCEPT
    sudo ip6tables -A DNS_LEAK_PREVENTION -d ::1/128 -p tcp --dport 53 -j ACCEPT
    sudo ip6tables -A DNS_LEAK_PREVENTION -p udp --dport 53 -j DROP
    sudo ip6tables -A DNS_LEAK_PREVENTION -p tcp --dport 53 -j DROP
    sudo ip6tables -I OUTPUT 1 -j DNS_LEAK_PREVENTION

    log "✅ Firewall rules applied - all DNS goes through Tor"
}

# 4. DISABLE DNS IN NETWORK MANAGER
disable_network_manager_dns() {
    log "🔧 Disabling NetworkManager DNS management..."

    if [[ -d /etc/NetworkManager ]]; then
        sudo tee /etc/NetworkManager/conf.d/99-nexus-no-dns.conf > /dev/null <<EOF
[main]
dns=none
systemd-resolved=false
EOF

        # Restart NetworkManager
        sudo systemctl restart NetworkManager 2>/dev/null || true
        log "✅ NetworkManager DNS disabled"
    fi
}

# 5. TEST FOR DNS LEAKS
test_dns_leaks() {
    log "🔍 Testing for DNS leaks..."

    # Test 1: Verify resolv.conf points to localhost
    if ! grep -q "nameserver 127.0.0.1" /etc/resolv.conf; then
        log "❌ LEAK DETECTED: /etc/resolv.conf not pointing to localhost"
        return 1
    fi
    log "✅ Test 1 passed: resolv.conf points to localhost"

    # Test 2: Check for external DNS in iptables
    if sudo iptables -L OUTPUT -n | grep -q "dpt:53" | grep -v "127.0.0.0/8"; then
        log "❌ LEAK DETECTED: iptables allows external DNS"
        return 1
    fi
    log "✅ Test 2 passed: iptables blocks external DNS"

    # Test 3: Attempt DNS query to external server (should fail)
    if timeout 5 dig @8.8.8.8 google.com +short &>/dev/null; then
        log "❌ LEAK DETECTED: Can query external DNS server"
        return 1
    fi
    log "✅ Test 3 passed: Cannot query external DNS"

    # Test 4: Verify Tor DNS is working
    if ! timeout 10 dig @127.0.0.1 check.torproject.org +short &>/dev/null; then
        log "⚠️  WARNING: Tor DNS not responding (may not be started yet)"
    else
        log "✅ Test 4 passed: Tor DNS is working"
    fi

    log "🎉 All DNS leak tests passed!"
    return 0
}

# Main execution
main() {
    log "🚀 Starting NeXuS DNS Leak Prevention System..."

    # Create log directory
    sudo mkdir -p /var/log/nexus-security
    sudo chown user:user /var/log/nexus-security

    # Execute prevention measures
    disable_system_dns
    configure_tor_dns
    block_external_dns
    disable_network_manager_dns

    # Test for leaks
    if test_dns_leaks; then
        log "✅ DNS Leak Prevention ACTIVE - All DNS goes through Tor"
        exit 0
    else
        log "❌ DNS Leak Prevention FAILED - System is NOT SECURE"
        exit 1
    fi
}

# Run main function
main "$@"

IPv6 Leak Prevention

#!/bin/bash
# /home/user/scripts/nexus-ipv6-leak-prevention.sh
# NeXuS IPv6 Leak Prevention - PARANOID MODE

set -euo pipefail

SCRIPT_NAME="nexus-ipv6-leak-prevention"
LOG_FILE="/var/log/nexus-security/${SCRIPT_NAME}.log"

log() {
    echo "[$(date +'%Y-%m-%d %H:%M:%S')] $*" | tee -a "$LOG_FILE"
}

# 1. DISABLE IPv6 IN KERNEL
disable_ipv6_kernel() {
    log "🚫 Disabling IPv6 in kernel..."

    # Kernel parameters
    sudo tee /etc/sysctl.d/99-nexus-disable-ipv6.conf > /dev/null <<EOF
# NeXuS IPv6 Leak Prevention
# IPv6 is a major leak vector - DISABLED COMPLETELY

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1
EOF

    # Apply immediately
    sudo sysctl -p /etc/sysctl.d/99-nexus-disable-ipv6.conf

    log "✅ IPv6 disabled in kernel"
}

# 2. DISABLE IPv6 IN NETWORK INTERFACES
disable_ipv6_interfaces() {
    log "🔧 Disabling IPv6 on all network interfaces..."

    # Get all network interfaces
    for interface in $(ip -o link show | awk -F': ' '{print $2}'); do
        if [[ "$interface" != "lo" ]]; then
            sudo sysctl -w net.ipv6.conf."$interface".disable_ipv6=1
            log "  ✅ Disabled IPv6 on $interface"
        fi
    done
}

# 3. BLOCK ALL IPv6 TRAFFIC WITH IP6TABLES
block_ipv6_traffic() {
    log "🔥 Blocking all IPv6 traffic with ip6tables..."

    # Flush existing rules
    sudo ip6tables -F
    sudo ip6tables -X

    # Default policies - DROP EVERYTHING
    sudo ip6tables -P INPUT DROP
    sudo ip6tables -P FORWARD DROP
    sudo ip6tables -P OUTPUT DROP

    # No exceptions - IPv6 is completely blocked
    log "✅ All IPv6 traffic blocked"
}

# 4. DISABLE IPv6 IN GRUB (PERMANENT)
disable_ipv6_grub() {
    log "⚙️  Adding IPv6 disable to GRUB configuration..."

    if [[ -f /etc/default/grub ]]; then
        # Backup GRUB config
        sudo cp /etc/default/grub /etc/default/grub.backup

        # Add ipv6.disable=1 to GRUB_CMDLINE_LINUX
        if ! grep -q "ipv6.disable=1" /etc/default/grub; then
            sudo sed -i 's/GRUB_CMDLINE_LINUX="/GRUB_CMDLINE_LINUX="ipv6.disable=1 /' /etc/default/grub
            sudo update-grub
            log "✅ IPv6 disabled in GRUB (requires reboot)"
        else
            log "  ℹ️  IPv6 already disabled in GRUB"
        fi
    fi
}

# 5. REMOVE IPv6 FROM /etc/hosts
clean_hosts_file() {
    log "🧹 Removing IPv6 entries from /etc/hosts..."

    sudo cp /etc/hosts /etc/hosts.backup
    sudo sed -i '/^[[:space:]]*::1/d' /etc/hosts
    sudo sed -i '/^[[:space:]]*fe80::/d' /etc/hosts
    sudo sed -i '/^[[:space:]]*ff02::/d' /etc/hosts

    log "✅ IPv6 entries removed from /etc/hosts"
}

# 6. TEST FOR IPv6 LEAKS
test_ipv6_leaks() {
    log "🔍 Testing for IPv6 leaks..."

    # Test 1: Verify IPv6 is disabled in kernel
    if [[ $(cat /proc/sys/net/ipv6/conf/all/disable_ipv6) -ne 1 ]]; then
        log "❌ LEAK DETECTED: IPv6 not disabled in kernel"
        return 1
    fi
    log "✅ Test 1 passed: IPv6 disabled in kernel"

    # Test 2: Check for IPv6 addresses on interfaces
    if ip -6 addr show | grep -q "inet6" | grep -v "::1/128"; then
        log "❌ LEAK DETECTED: IPv6 addresses found on interfaces"
        return 1
    fi
    log "✅ Test 2 passed: No IPv6 addresses on interfaces"

    # Test 3: Verify ip6tables blocks everything
    if ! sudo ip6tables -L OUTPUT | grep -q "policy DROP"; then
        log "❌ LEAK DETECTED: ip6tables not blocking all traffic"
        return 1
    fi
    log "✅ Test 3 passed: ip6tables blocks all traffic"

    # Test 4: Attempt IPv6 ping (should fail)
    if timeout 5 ping6 -c 1 google.com &>/dev/null; then
        log "❌ LEAK DETECTED: IPv6 connectivity still works"
        return 1
    fi
    log "✅ Test 4 passed: No IPv6 connectivity"

    log "🎉 All IPv6 leak tests passed!"
    return 0
}

# Main execution
main() {
    log "🚀 Starting NeXuS IPv6 Leak Prevention System..."

    # Create log directory
    sudo mkdir -p /var/log/nexus-security
    sudo chown user:user /var/log/nexus-security

    # Execute prevention measures
    disable_ipv6_kernel
    disable_ipv6_interfaces
    block_ipv6_traffic
    disable_ipv6_grub
    clean_hosts_file

    # Test for leaks
    if test_ipv6_leaks; then
        log "✅ IPv6 Leak Prevention ACTIVE - IPv6 completely disabled"
        exit 0
    else
        log "❌ IPv6 Leak Prevention FAILED - System is NOT SECURE"
        exit 1
    fi
}

# Run main function
main "$@"

WebRTC Leak Prevention

#!/bin/bash
# /home/user/scripts/nexus-webrtc-leak-prevention.sh
# NeXuS WebRTC Leak Prevention - PARANOID MODE

set -euo pipefail

SCRIPT_NAME="nexus-webrtc-leak-prevention"
LOG_FILE="/var/log/nexus-security/${SCRIPT_NAME}.log"
FIREFOX_PROFILES="$HOME/.mozilla/firefox"
CHROMIUM_PROFILES="$HOME/.config/chromium"

log() {
    echo "[$(date +'%Y-%m-%d %H:%M:%S')] $*" | tee -a "$LOG_FILE"
}

# 1. DISABLE WebRTC IN FIREFOX
disable_firefox_webrtc() {
    log "🦊 Disabling WebRTC in Firefox profiles..."

    if [[ ! -d "$FIREFOX_PROFILES" ]]; then
        log "  ℹ️  No Firefox profiles found"
        return 0
    fi

    # Find all Firefox profiles
    for profile in "$FIREFOX_PROFILES"/*.default*; do
        if [[ -d "$profile" ]]; then
            log "  🔧 Configuring profile: $(basename "$profile")"

            # Create or update user.js
            cat >> "$profile/user.js" <<EOF
// NeXuS WebRTC Leak Prevention - PARANOID MODE
// Disable WebRTC completely to prevent IP leaks

// Disable WebRTC entirely
user_pref("media.peerconnection.enabled", false);

// Disable WebRTC device enumeration
user_pref("media.navigator.enabled", false);

// Disable WebRTC getUserMedia
user_pref("media.navigator.permission.disabled", true);

// Disable WebRTC ICE (IP leak vector)
user_pref("media.peerconnection.ice.default_address_only", true);
user_pref("media.peerconnection.ice.no_host", true);

// Disable mDNS hostname leaks
user_pref("media.peerconnection.ice.proxy_only_if_behind_proxy", true);

// Force WebRTC traffic through proxy (if enabled)
user_pref("media.peerconnection.ice.tcp", false);
EOF

            log "    ✅ WebRTC disabled in $(basename "$profile")"
        fi
    done
}

# 2. DISABLE WebRTC IN CHROMIUM/CHROME
disable_chromium_webrtc() {
    log "🌐 Configuring Chromium/Chrome WebRTC leak prevention..."

    # Chromium policy directory
    POLICY_DIR="/etc/chromium/policies/managed"
    sudo mkdir -p "$POLICY_DIR"

    # Create WebRTC leak prevention policy
    sudo tee "$POLICY_DIR/nexus-webrtc-prevention.json" > /dev/null <<EOF
{
  "WebRtcIPHandling": "disable_non_proxied_udp",
  "WebRtcUdpPortRange": "",
  "VideoCaptureAllowed": false,
  "AudioCaptureAllowed": false,
  "MediaRouterEnabled": false
}
EOF

    log "✅ Chromium policy created"
}

# 3. BLOCK STUN/TURN SERVERS (WebRTC signaling)
block_stun_servers() {
    log "🔥 Blocking STUN/TURN servers..."

    # Common STUN/TURN servers
    STUN_SERVERS=(
        "stun.l.google.com"
        "stun1.l.google.com"
        "stun2.l.google.com"
        "stun3.l.google.com"
        "stun4.l.google.com"
        "stun.services.mozilla.com"
        "stun.stunprotocol.org"
        "stun.ekiga.net"
        "stun.ideasip.com"
        "stun.voiparound.com"
        "stun.voipbuster.com"
    )

    # Add to /etc/hosts (null route)
    sudo cp /etc/hosts /etc/hosts.webrtc-backup

    for server in "${STUN_SERVERS[@]}"; do
        if ! grep -q "$server" /etc/hosts; then
            echo "0.0.0.0 $server" | sudo tee -a /etc/hosts > /dev/null
            log "  ✅ Blocked $server"
        fi
    done

    # Block STUN/TURN ports (3478, 5349)
    sudo iptables -A OUTPUT -p udp --dport 3478 -j DROP
    sudo iptables -A OUTPUT -p tcp --dport 3478 -j DROP
    sudo iptables -A OUTPUT -p udp --dport 5349 -j DROP
    sudo iptables -A OUTPUT -p tcp --dport 5349 -j DROP

    log "✅ STUN/TURN servers blocked"
}

# 4. TEST FOR WebRTC LEAKS
test_webrtc_leaks() {
    log "🔍 Testing for WebRTC leaks..."

    # Test 1: Verify Firefox user.js exists
    if [[ -d "$FIREFOX_PROFILES" ]]; then
        for profile in "$FIREFOX_PROFILES"/*.default*; do
            if [[ -f "$profile/user.js" ]] && grep -q "media.peerconnection.enabled.*false" "$profile/user.js"; then
                log "✅ Test 1 passed: Firefox WebRTC disabled"
            else
                log "⚠️  Warning: Firefox profile may not have WebRTC disabled"
            fi
        done
    fi

    # Test 2: Verify Chromium policy exists
    if [[ -f "/etc/chromium/policies/managed/nexus-webrtc-prevention.json" ]]; then
        log "✅ Test 2 passed: Chromium policy exists"
    else
        log "⚠️  Warning: Chromium policy not found"
    fi

    # Test 3: Verify STUN servers are blocked
    if grep -q "stun.l.google.com" /etc/hosts; then
        log "✅ Test 3 passed: STUN servers blocked in /etc/hosts"
    else
        log "⚠️  Warning: STUN servers not blocked"
    fi

    # Test 4: Verify iptables blocks STUN ports
    if sudo iptables -L OUTPUT -n | grep -q "dpt:3478"; then
        log "✅ Test 4 passed: STUN ports blocked by iptables"
    else
        log "⚠️  Warning: STUN ports not blocked"
    fi

    log "🎉 WebRTC leak prevention configured!"
    log "⚠️  NOTE: Users must restart browsers for changes to take effect"
}

# Main execution
main() {
    log "🚀 Starting NeXuS WebRTC Leak Prevention System..."

    # Create log directory
    sudo mkdir -p /var/log/nexus-security
    sudo chown user:user /var/log/nexus-security

    # Execute prevention measures
    disable_firefox_webrtc
    disable_chromium_webrtc
    block_stun_servers

    # Test configuration
    test_webrtc_leaks

    log "✅ WebRTC Leak Prevention ACTIVE"
}

# Run main function
main "$@"

🎭 LAYER 3: TRAFFIC OBFUSCATION & ANTI-CORRELATION

Timing Attack Prevention

#!/usr/bin/env python3
# /home/user/scripts/nexus-traffic-obfuscation.py
# NeXuS Traffic Obfuscation Engine - PARANOID MODE

import asyncio
import random
import time
import logging
from typing import List, Optional
from dataclasses import dataclass
from enum import Enum

logging.basicConfig(
    level=logging.INFO,
    format='[%(asctime)s] %(levelname)s: %(message)s'
)
logger = logging.getLogger(__name__)

class ObfuscationMode(Enum):
    """Traffic obfuscation strategies"""
    TIMING_RANDOMIZATION = "timing_randomization"
    PACKET_PADDING = "packet_padding"
    COVER_TRAFFIC = "cover_traffic"
    BURST_SHAPING = "burst_shaping"
    DECOY_ROUTING = "decoy_routing"

@dataclass
class TrafficProfile:
    """Traffic pattern profile"""
    min_delay_ms: int = 100
    max_delay_ms: int = 5000
    padding_size_min: int = 128
    padding_size_max: int = 1500
    cover_traffic_ratio: float = 0.3  # 30% dummy traffic
    burst_size_min: int = 1
    burst_size_max: int = 10

class TrafficObfuscator:
    """
    Advanced traffic obfuscation engine to prevent timing attacks,
    traffic correlation, and behavioral fingerprinting.

    Defends against state-level adversaries performing:
    - End-to-end timing correlation
    - Packet size analysis
    - Burst pattern recognition
    - Inter-packet delay fingerprinting
    """

    def __init__(self, profile: TrafficProfile = TrafficProfile()):
        self.profile = profile
        self.cover_traffic_task: Optional[asyncio.Task] = None
        logger.info("🎭 Traffic Obfuscator initialized")

    async def randomize_timing(self, min_delay: Optional[int] = None,
                                max_delay: Optional[int] = None) -> None:
        """
        Add random delays to prevent timing correlation attacks.

        Timing attacks work by correlating entry/exit traffic patterns.
        Random delays break this correlation at the cost of latency.
        """
        min_ms = min_delay or self.profile.min_delay_ms
        max_ms = max_delay or self.profile.max_delay_ms

        # Exponential distribution (more realistic than uniform)
        delay_ms = random.expovariate(1.0 / ((min_ms + max_ms) / 2))
        delay_ms = max(min_ms, min(max_ms, delay_ms))

        await asyncio.sleep(delay_ms / 1000.0)

    def add_padding(self, data: bytes, target_size: Optional[int] = None) -> bytes:
        """
        Add random padding to packets to prevent size-based fingerprinting.

        Packet size analysis can reveal:
        - Protocol (SSH vs HTTP vs BitTorrent)
        - Application (Gmail vs Facebook)
        - User behavior (typing vs downloading)

        Padding makes all packets look identical in size.
        """
        current_size = len(data)

        if target_size is None:
            target_size = random.randint(
                max(current_size, self.profile.padding_size_min),
                self.profile.padding_size_max
            )

        if target_size <= current_size:
            return data  # No padding needed

        padding_size = target_size - current_size
        padding = random.randbytes(padding_size)

        # Format: [original_size:4 bytes][data][padding]
        padded = len(data).to_bytes(4, 'big') + data + padding

        logger.debug(f"Padded {current_size} bytes to {len(padded)} bytes")
        return padded

    def remove_padding(self, padded_data: bytes) -> bytes:
        """Remove padding added by add_padding()"""
        if len(padded_data) < 4:
            return padded_data

        original_size = int.from_bytes(padded_data[:4], 'big')
        return padded_data[4:4+original_size]

    async def generate_cover_traffic(self, duration_seconds: int = 3600) -> None:
        """
        Generate continuous dummy traffic to mask real traffic patterns.

        Cover traffic prevents:
        - Traffic correlation (can't distinguish real vs fake)
        - Silence periods (always appears active)
        - Behavioral analysis (constant background noise)

        Cost: Bandwidth and battery consumption
        """
        logger.info(f"🎭 Generating cover traffic for {duration_seconds}s")

        start_time = time.time()
        packet_count = 0

        while (time.time() - start_time) < duration_seconds:
            # Random size dummy packet
            dummy_size = random.randint(64, 1500)
            dummy_packet = random.randbytes(dummy_size)

            # Send to black hole (or Tor if you want full obfuscation)
            await self._send_dummy_packet(dummy_packet)

            # Random delay between packets
            await self.randomize_timing(50, 500)

            packet_count += 1

        logger.info(f"✅ Generated {packet_count} cover traffic packets")

    async def _send_dummy_packet(self, packet: bytes) -> None:
        """Send dummy packet (implement actual sending logic here)"""
        # In production: send through Tor to random .onion address
        await asyncio.sleep(0.001)  # Simulate network delay

    async def shape_burst(self, packets: List[bytes]) -> List[bytes]:
        """
        Shape traffic bursts to prevent burst pattern fingerprinting.

        Burst patterns reveal:
        - Application (web browsing: request→burst, video: constant burst)
        - User behavior (reading vs downloading)

        Solution: Break large bursts into smaller random bursts
        """
        shaped_packets = []

        burst_size = random.randint(
            self.profile.burst_size_min,
            self.profile.burst_size_max
        )

        for i, packet in enumerate(packets):
            shaped_packets.append(packet)

            # Add delay between bursts
            if (i + 1) % burst_size == 0:
                await self.randomize_timing()

        return shaped_packets

    async def decoy_routing(self, destination: str, real_data: bytes) -> None:
        """
        Decoy routing: Send fake traffic to decoy destinations.

        Adversaries monitoring your traffic see connections to:
        - google.com (decoy)
        - facebook.com (decoy)
        - bank.com (decoy)
        - hidden.onion (real)

        They cannot determine which is real without breaking encryption.
        """
        decoy_destinations = [
            "google.com",
            "facebook.com",
            "twitter.com",
            "reddit.com",
            "wikipedia.org",
            "cloudflare.com"
        ]

        # Send decoy traffic in parallel with real traffic
        tasks = []

        # Real traffic (with obfuscation)
        tasks.append(self._send_real_traffic(destination, real_data))

        # Decoy traffic
        num_decoys = random.randint(2, 5)
        for _ in range(num_decoys):
            decoy = random.choice(decoy_destinations)
            decoy_data = random.randbytes(len(real_data))
            tasks.append(self._send_decoy_traffic(decoy, decoy_data))

        await asyncio.gather(*tasks)

    async def _send_real_traffic(self, destination: str, data: bytes) -> None:
        """Send real traffic (implement actual logic)"""
        await self.randomize_timing()
        logger.info(f"📤 Sent real traffic to {destination} ({len(data)} bytes)")

    async def _send_decoy_traffic(self, destination: str, data: bytes) -> None:
        """Send decoy traffic (implement actual logic)"""
        await self.randomize_timing()
        logger.debug(f"🎭 Sent decoy traffic to {destination} ({len(data)} bytes)")

    async def start_cover_traffic(self) -> None:
        """Start continuous cover traffic generation"""
        if self.cover_traffic_task and not self.cover_traffic_task.done():
            logger.warning("Cover traffic already running")
            return

        self.cover_traffic_task = asyncio.create_task(
            self.generate_cover_traffic(duration_seconds=86400)  # 24 hours
        )
        logger.info("✅ Cover traffic started")

    async def stop_cover_traffic(self) -> None:
        """Stop cover traffic generation"""
        if self.cover_traffic_task:
            self.cover_traffic_task.cancel()
            try:
                await self.cover_traffic_task
            except asyncio.CancelledError:
                pass
            logger.info("🛑 Cover traffic stopped")

# Example usage
async def main():
    """Demonstration of traffic obfuscation techniques"""
    obfuscator = TrafficObfuscator()

    # Example 1: Send traffic with timing randomization
    print("\n🔹 Example 1: Timing randomization")
    for i in range(5):
        await obfuscator.randomize_timing()
        print(f"  Sent packet {i+1}")

    # Example 2: Packet padding
    print("\n🔹 Example 2: Packet padding")
    original_data = b"Secret message"
    padded_data = obfuscator.add_padding(original_data, target_size=1500)
    print(f"  Original size: {len(original_data)} bytes")
    print(f"  Padded size: {len(padded_data)} bytes")
    recovered_data = obfuscator.remove_padding(padded_data)
    print(f"  Recovered: {recovered_data}")

    # Example 3: Cover traffic (5 seconds only for demo)
    print("\n🔹 Example 3: Cover traffic (5 seconds)")
    await obfuscator.generate_cover_traffic(duration_seconds=5)

    # Example 4: Decoy routing
    print("\n🔹 Example 4: Decoy routing")
    await obfuscator.decoy_routing("secret.onion", b"Real secret data")

    print("\n✅ Demonstration complete")

if __name__ == "__main__":
    asyncio.run(main())

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