Enhance iptables rules for security and logging #75
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- Added rate-limiting to SSH traffic:
iptables -A INPUT -p tcp --dport 22 -m limit --limit 5/min -j ACCEPT
Limits SSH connection attempts to 5 per minute to mitigate brute force attacks.
- Block invalid TCP flags combinations:
- iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP
Drops packets with no TCP flags (null scan attack).
- iptables -A INPUT -p tcp --tcp-flags FIN,ACK FIN -j DROP
Drops packets with FIN and ACK flags (XMAS scan mitigation).
- Added logging for dropped packets:
- iptables -A INPUT -j LOG --log-prefix "INPUT_DROP: "
Logs all dropped INPUT packets with the specified prefix.
- iptables -A OUTPUT -j LOG --log-prefix "OUTPUT_DROP: "
Logs all dropped OUTPUT packets with the specified prefix.
- Replaced deprecated `-m state --state` with `-m conntrack --ctstate`:
- Ensures compatibility with modern iptables versions.
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-m state --statewith-m conntrack --ctstateso i Improved security by limiting SSH connection attempts and blocking invalid TCP flag combinations, enhanced logging to track dropped packets and ensured compatibility with newer iptables versions by replacing deprecated -m state with -m conntrack