setup_dns_blocker.sh turns this PC into a DNS server that serves the
identical /etc/hosts blocklist to the whole LAN with no per-device app,
by feeding generate_hosts_file.sh output into dnsmasq via addn-hosts
(same StevenBlack variant + custom entries + unblocks). Adds status/
refresh subcommands, a daily refresh timer, Restart=always, and logging
to /var/log/dns-blocker/.
Because the ISP router cannot advertise a custom DNS server, a dhcp/
dhcp-off mode makes the PC the LAN DHCP server (static IP via nmcli with
a gateway-ping self-check and safe, always-online rollback), handing out
itself as the DNS server so every device is blocked automatically.
setup_wireguard_ssh.sh gains an allow-dns subcommand that opens DNS (53,
LAN saddr) and DHCP (67) in the single-owner nftables ruleset. The DHCP
accept rule is placed before 'ct state invalid drop' because the
0.0.0.0->255.255.255.255 DHCP broadcast is classified INVALID and was
otherwise dropped. Firewall detection now reads the actual loaded ruleset
(a ruleset can be loaded while nftables.service reads inactive) and avoids
a grep -q/pipefail SIGPIPE false-negative.
Verified end-to-end: Pixel-6a leased 192.168.1.82 with DNS 192.168.1.43;
youtube.com blocked, legit sites resolve. Regression tests added.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018pqSnrLt8QoWup7n2Ymk77
