Security Protocol v2.0 Ready

PortGuard: Keep Your Services Invisible to Scanners

PortGuard combines a modified fwknop-based server with a cross-platform client that supports the fwknop SPA protocol. Ports stay closed by default and open temporarily only after a valid AES/GPG-signed packet is verified.

Quick Server Install

Installs the latest open-source package built by GitHub Actions from the PortGuard server repository.

Guide
curl -fsSL https://portguard.net/install.sh | sudo bash
Live Client Preview
Built for fwknop-compatible workflows

Traditional Exposure Mode (Risk)

  • Ports remain open all day and are continuously probed by global scanners.
  • Exposed services face brute-force attempts and exploit attacks directly.
  • Firewall allowlists become complex to maintain and lack dynamic flexibility.

PortGuard Mode (Solution)

  • Default Deny: Ports are completely invisible before authorization (stealth).
  • SPA Auth: Only specially formatted encrypted single packets can trigger access.
  • Dynamic Access: Temporarily allow only the source IP, then close automatically.

Core Features

Core Security Features

Strong defaults for teams that want SSH, admin panels, and private services to disappear until authorization is intentional.

Efficient SPA Communication

Send fwknop-compatible single-packet authorization without TCP handshake overhead, with strong stealth.

AES/GPG + HMAC

Integrated SHA256 integrity checks ensure commands are authentic and untampered.

Full Port Stealth

Default DROP behavior makes services appear unreachable to scanners.

Replay Attack Resistance

Time-window validation plus integrity checks quickly invalidates old packets.

Tutorial PortGuard

A cleaner fwknop-compatible client for every device.

PortGuard Client supports the fwknop SPA protocol. Profiles, one-tap SPA, QR import, encrypted export, and activation stay compatible with fwknopd and PortGuard Server workflows.

One-tap SPA Send authorized knocks without command-line friction.
Encrypted profiles Keep local configs protected at rest.
QR import Move profiles between devices quickly.

How It Works

Security Workflow

PortGuard runs at the firewall edge of protected servers. It continuously inspects network traffic for authorization packets without exposing service handshakes externally.

1
Generate Authorization Packet

The client uses keys and a timestamp to generate an encrypted single packet.

2
Handshake-less Delivery

The packet is sent via UDP and similar methods, making handshake-based probing ineffective.

3
Dynamic Open

After validation, the server temporarily allows the source IP and then automatically removes the rule.

PORT_GUARD_DAEMON STATUS: MENDENGARKAN
[INFO] Menyadap paket SPA di eth0...
[CMD] Paket terdeteksi dari 124.6.x.x
[AUTH] HMAC SHA256 terverifikasi. Timestamp valid.
[AUTH] Mendekripsi payload dengan AES-256-CBC...
[FIREWALL] Membuka port 22 untuk 124.6.x.x selama 30 dtk.
_

Use Cases

SSH Remote Operations

Protect port 22 and make it visible only briefly after an admin sends SPA.

Multi-Cloud Security

Unified access control across AWS/Azure and more to reduce exposure.

IoT Device Management

Protect IoT control interfaces and avoid direct public exposure.

ACL Automation

Combine scripts and rule cycles to automate temporary authorization.

Downloads and Installation

Supports multi-platform clients and server-side packages

Windows Client

portguard-client-2.2.1-x64-setup.exe

macOS Client

portguard-client-2.2.2-18-macos.dmg

Apple App Store

iPhone & iPad

Go to Store

Android App

fwknopc_2_6_11.apk

Download APK

Linux Server

Debian, Ubuntu, Rocky, CentOS, OpenWrt

Server Packages
Security Tip: Please verify MD5/SHA256 fingerprints after downloading.

Server Packages

Install PortGuard Server on Debian, Ubuntu, Rocky, CentOS, and OpenWrt

Use the quick installer for supported Linux servers, or download the latest package generated from the open-source GitHub Actions release pipeline.

Quick Install

One command server setup

curl -fsSL https://portguard.net/install.sh | sudo bash

The script detects the operating system, selects the matching package from the GitHub release manifest, verifies SHA256, installs dependencies, and leaves fwknopd ready for configuration export to PortGuard Client.

Open Source Release

Packages synced from GitHub

These packages are built automatically by GitHub Actions from the public PortGuard server source code.

Latest Release
System Version Architecture Package Muat turun
Loading packages from GitHub release...

FAQ & kasus penggunaan

Terakhir diperbarui:

What is the relationship between PortGuard and fwknop?

PortGuard is built around the fwknop SPA protocol. PortGuard Client is a cross-platform client that sends fwknop-compatible SPA packets, while PortGuard Server is a modified server based on the upstream fwknop project. Compared with traditional sequence-based port knocking, this single encrypted packet model is faster, stealthier, and resistant to replay attacks.

Bolehkah saya menjana satu profil dan menggunakan satu ketukan untuk membenarkan IP tertentu mengakses setiap port perkhidmatan?

ya. Konfigurasikan stanza akses pelayan dengan OPEN_PORTS ANY dan gunakan profil pelanggan dengan ACCESS ANY. Profil boleh dijana dan diimport sekali, kemudian digunakan semula. Setiap ketukan yang sah mencipta peraturan IP sumber sementara yang membenarkan IP yang dipilih oleh ALLOW_IP mencapai semua port perkhidmatan TCP dan UDP sehingga FW_TIMEOUT tamat tempoh. Selepas tamat tempoh, hantar ketukan baharu. Ini ialah mod keistimewaan tinggi: gunakan tamat masa yang singkat, lindungi profil dan kekunci, dan ingat bahawa tembok api awan huluan, peraturan penghala dan pengesahan perkhidmatan masih terpakai.

Bagaimana perbandingan fwknop dengan tnock?

Keduanya bertujuan menyamarkan port jaringan, tetapi fwknop adalah solusi SPA yang lebih maju. tnock dan daemon berbasis urutan serupa harus mendeteksi pola percobaan koneksi di banyak port tertutup, sehingga lebih lambat dan rentan replay. fwknop mengatasinya dengan mengirim satu payload bertanda tangan kriptografis dan bertimestamp. Keunggulan: keamanan jauh lebih tinggi, tahan replay, dan integrasi mulus dengan firewall modern.

Bagaimana cara membuat website atau layanan privat saya hanya bisa diakses orang tertentu?

By default, PortGuard Server, modified from fwknop, configures your server's firewall to block all inbound traffic to your service port. The service appears completely offline to the public. When an authorized user needs access, they use PortGuard Client with their unique cryptographic key to send a fwknop-compatible Single Packet Authorization (SPA) packet. Once verified, the server dynamically whitelists their current IP address for a brief period.

Bagaimana memastikan keamanan dan privasi NAS yang terekspos ke jaringan publik tanpa kebocoran data?

Mengekspos NAS langsung ke internet sangat berisiko karena botnet dan pemindaian terus-menerus. Umumnya ada dua solusi aman:

  • Rencana 1: Cloudflare Zero Trust (Tunnels) Lalu lintas NAS dialihkan melalui jaringan Cloudflare tanpa membuka port inbound. Kelebihan: sangat mudah diatur, tidak perlu IP publik, ada lapisan WAF tambahan. Kekurangan: trafik melewati pihak ketiga sehingga bergantung pada kebijakan privasi Cloudflare; kecepatan sering terbatas oleh routing free tier, kurang ideal untuk streaming file media besar.
  • Rencana 2: Public IP self-hosted + fwknop Port Knocking Anda membuka port di router tetapi melindunginya dengan fwknop (SPA). Port tetap tidak terlihat di internet publik dan hanya terbuka saat Anda mengirim paket akses valid bertanda tangan kriptografis. Kelebihan: privasi data tinggi karena tidak lewat pihak ketiga, serta kecepatan hardware maksimal karena koneksi langsung (bagus untuk streaming video). Kekurangan: memerlukan public IP nyata dan setup awal yang sedikit lebih teknis.

Apakah fwknop PortGuard memperlambat koneksi setelah port dibuka?

No. The fwknop-compatible PortGuard Server only handles the initial authorization packet. Once the firewall rule is dynamically created and your IP is authorized, your connection via SSH, WireGuard, or directly to your NAS operates directly between your client and the server at full line speed.

Trusted by DevOps and Security Experts Worldwide

"After deploying PortGuard on our bastion hosts, SSH scan noise in logs dropped significantly."
- SysAdmin senior, TechGroup
"SPA's one-way, handshake-less design is highly practical, balancing stealth and operability."
- Peneliti keamanan, @CyberNode
"iptables integration was smooth, and we've rolled it out at scale in production."
- Lead DevOps, Fintech Corp

Official Contact

Need help with PortGuard?

For purchase recovery, activation issues, deployment questions, or security reports, contact the official PortGuard support mailbox.

[email protected]