Firewall Manager

GMSSH Firewall Manager is a visual system-level firewall management tool for Linux servers. It provides an intuitive graphical interface covering Port Rules, IP Rules, Inbound Forwarding, and Outbound Forwarding, with a global firewall toggle and Ping blocking control.

Core Features

Initialization

Zero-Barrier Firewall Setup. If the firewall is not running on first launch, a guide page prompts one-click activation.

• Startup Guide: Center prompt "Firewall not started, please click to start" with "Start Now" button.
• Firewall Toggle: Bottom-left global on/off switch.
• Block Ping Toggle: Bottom-left toggle — when enabled, the server won't respond to ICMP Ping requests for enhanced stealth.

Port Rules

Server Port Access Policy Center. Manages port access policies with fine-grained control by protocol, port range, direction, and source IP.

• Rule List: Table showing protocol (TCP/UDP), port range, status, policy (Allow/Deny), direction (Inbound/Outbound), source IP, extra info, and description.
• Multi-Filter: Search box (port, IP, description) with status, policy, and direction filters.
• Create Port Rule: Top-right button with form:
  • Protocol: TCP, UDP, or other.
  • Port: Target port or port range.
  • Direction: Inbound or Outbound.
  • Source IP: Allowed source IP (empty or 0.0.0.0/0 for all).
  • Policy: Toggle Allow/Deny.
  • Description: Rule notes (max 100 characters).
  • Batch Create: ⊕/⊖ buttons to create multiple rules at once.
• Rule Actions: Each row has disable, edit, and delete buttons.
• Export Rules: Export current rules to file for backup or migration.
• Import Rules: Import rules from file for batch configuration.

IP Rules

IP Access Control Policy Management. Fine-grained access control by IP address with inbound/outbound allow/deny policies.

• Rule List: Table showing IP address, policy, direction, extra info, and description.
• Multi-Filter: Search by IP or description with policy and direction filters.
• Create IP Rule: Top-right button with form:
  • Source IP: Target IP address.
  • Direction: Inbound or Outbound.
  • Policy: Toggle Allow/Deny.
  • Description: Rule notes (max 100 characters).
  • Batch Create: ⊕/⊖ buttons for multiple rules.
• Export/Import Rules: File-based backup and batch import.

Inbound Forwarding

Inbound Traffic Forwarding. Forward external requests through local ports to target servers — for NAT traversal, port mapping, and similar scenarios.

• Forwarding List: Table showing protocol, inbound IP, local port, target IP, target port, and description.
• Search: Search by port, IP, or description.
• Create Inbound Forward: Top-right button with config panel. Logic: "Inbound IP accesses local port, traffic forwards to target IP and target port".
  • Protocol: Forwarding protocol type.
  • Inbound IP: Source IP of inbound requests.
  • Local Port: Port receiving traffic.
  • Target IP: Forward destination IP.
  • Target Port: Forward destination port.
  • Description: Rule notes (max 100 characters).
  • Batch Create: ⊕/⊖ buttons for multiple rules.
• Export/Import: File-based backup and import.

Outbound Forwarding

Outbound Traffic Forwarding. Advanced outbound traffic control with custom protocol, source IP, and source port rules.

• Forwarding List: Table showing all outbound forwarding rules.
• Add Port Forward Rule: Form with:
  • Protocol: Protocol type (custom TCP, etc.) dropdown.
  • Source IP: Source IP (supports "All IP addresses").
  • Source Port: Source port (supports "All Ports").
  • Forward All Destinations: Toggle to specify target IP and port (empty = all).
  • Auto Replace Source IP: Toggle for source address masquerading.
  • Description: Rule notes (max 100 characters).
  • Multi-Rule Create: ⊕/⊖ buttons for batch creation.
• Export/Import: File-based backup and import.

Global Controls

Two global control toggles in the bottom-left corner:

• Firewall Toggle: One-click enable/disable with blue (on) / gray (off) visual indicators.
• Block Ping Toggle: When enabled, the server won't respond to ICMP Ping requests, hiding online status for enhanced security.