tmpfs.tech · all tracks · Firewall (nftables)

Always trust loopback

Firewall (nftables) · easy · live throwaway Linux box · 3 tiered hints

Author /etc/nftables.conf with the base (table inet filter, input chain: type filter hook input, policy drop) plus a rule that accepts ALL traffic arriving on the loopback interface.

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More Firewall (nftables) challenges

Author and reason about nftables rulesets — filtering, NAT and policy.

• Accept Related ICMP Errorseasy · in-browser
• Author a base nftables ruleseteasy
• Define a Variable for WAN Interfaceeasy · in-browser
• Drop Invalid Conntrack Earlyeasy · in-browser
• Idempotent ruleset headereasy · in-browser
• Include a Drop-In Ruleset Fileeasy · in-browser
• Named hook priorityeasy · in-browser
• Output chain accepteasy · in-browser

See all Firewall (nftables) challenges →

FAQ

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