Lets SSH terminal access reach this PC from a phone on a different network
(mobile data vs home broadband), using only FOSS/free software: self-hosted
WireGuard (no relay/coordination server), DuckDNS for the dynamic public IP,
and a default-drop nftables firewall so sshd is never exposed to the WAN
directly -- only the WireGuard UDP port is forwarded, SSH is reachable only
through the tunnel or LAN.
Verified fully end-to-end (phone on mobile data, real handshake + SSH login).
Several bugs only surfaced through live execution and were fixed in place:
a DNS=1.1.1.1 line that broke all phone DNS once the tunnel was active, a
require_root/sudo arg-forwarding bug, hostname/dig not being installed on a
minimal Arch system, a bash RETURN-trap scoping bug, and a DuckDNS cron-dedup
that would have deleted an unrelated pre-existing Joplin DuckDNS cron entry.
Also whitelists the WireGuard/F-Droid/ConnectBot apps (plus the todo app) in
phone_focus_mode's WHITELIST so the GPS-based focus daemon doesn't disable
them. Adds "iif" (nftables keyword) to the codespell ignore-list since it
was flagged as a false-positive typo of "if".
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TUSBRyujRMuGiUitGP8gET
