Create Firewall Rules Script for Service Security

Description

Create a bash script to configure iptables firewall rules limiting egress traffic to internal networks only and allowing ingress traffic only for SSH (22), HTTP (80), and HTTPS (443).

Implementation Tasks

Script Features

Input validation
Error handling
Logging
Backup functionality
Rule verification
Restoration capability

Network Rules

Define internal networks
Configure ingress ports
Set egress restrictions
Allow DNS resolution
Configure logging

Safety Measures

Backup existing rules
Verification steps
Rollback capability
SSH safety check