The Hub no longer asks a STUN server, a public DNS resolver or a "what
is my IP" service for the home IP address. The DDNS update asks Njal.la
to use the address the request comes from ("&auto"), reads back the
address Njal.la says it recorded and saves it to
/var/lib/secrets/external-ip. Njal.la is the only third party that
learns the address; it has to, to publish it.
- Add app/sovran_systemsos_web/ddns_update.py, installed as
/etc/sovran/ddns-update.py and run by sovran-ddns-update.service. It
runs curl --ipv4 without redirects, accepts only a public IPv4
address, and rewrites the file atomically and only when the address
changes. Stored "&a=${IP}" URLs are converted when they are used and
"&quiet" is dropped.
- Rewrite modules/core/njalla.nix around that runner and delete
modules/core/public-ip.nix. Setting a sovran_systemsOS.publicIP.*
option now fails with a message that says where the address comes
from. Activation removes the old scripts in /var/lib/sovran. The
existing external-ip file keeps working.
- server.py reads the saved address and starts
sovran-ddns-update.service after a domain is saved, instead of looking
the address up itself.
- Element calling uses sovran_systemsOS.elementCalling.externalIP if
set, otherwise the saved address, and fails with a clear message when
neither exists or the address is not public. It no longer falls back
to STUN. livekit-external-ip.path re-runs livekit-turn-setup and
starts LiveKit when the address changes.
- Add tests/test_ddns_update.py.
The public IP was previously detected independently in three places,
each contacting a different third party: the Hub (HTTPS echo via
api.ipify.org / ifconfig.me / icanhazip.com on every API call and
background tick), DDNS (myip.opendns.com via OpenDNS), and LiveKit
(embedded STUN). Consolidate into a single detector with one shared
cache so every consumer reads the same value with minimal exposure.
- add modules/core/public-ip.nix: installs /var/lib/sovran/public-ip.py
(pure Python stdlib, no new deps) writing /var/lib/secrets/external-ip
- detection chain (first success wins): explicit pin, fresh cache
(default TTL 300s), STUN binding request over UDP (one packet, no
metadata), DNS myip.opendns.com query, then OPT-IN HTTPS echo
(publicIP.httpsEcho, empty by default — never contacted unless listed)
- privacy: while the cache is fresh zero third parties are contacted;
at most one party learns the IP per refresh interval, via the least
exposing mechanism available
- hub (server.py): _get_external_ip() now reads the shared detector /
cache instead of calling ipify/ifconfig/icanhazip directly
- ddns (njalla.nix): use the shared detector instead of a separate
OpenDNS dig; allow the hardened service to write /var/lib/secrets
- element-calling: livekit-turn-setup falls back to the shared
detector on cold boot; add LiveKit webhooks to lk-jwt-service
(sfu_webhook) so abrupt disconnects are cleaned up immediately;
set LIVEKIT_SANITY_CHECK_INTERVAL_SECONDS=60 as a missed-webhook
guard; drop the dead services.livekit.settings block and set
openFirewall=false (Caddy fronts the SFU; no public 7880/tcp)
- new options: sovran_systemsOS.publicIP.{stunServer,stunPort,
dnsResolver,httpsEcho,cacheTTL}