A premium player and a third-party player sharing a username could not both be
online. Whichever logged in second was kicked with "You are already connected to
this proxy!" -- even though the UUID rewrite had already made them two distinct
players on the backend. Velocity's player registry is keyed on the NAME (lowercased),
not the UUID, so two identities holding one name are one player as far as the proxy
is concerned, and the reclaim invariant the rewrite buys is invisible to it.
The fix needs no plugin and no state, because Velocity honours the name in the
hasJoined RESPONSE rather than pinning the one the client sent at login-start --
established by a real login, not by reading the source. So the multiplexer hands
back a different name and the collision is simply gone.
A third-party player whose name belongs to a Mojang account now joins as
PREFIX_name (LS_steve). Everyone else keeps their own name: the rename fires only
on an actual collision, decided by asking api.mojang.com whether the name is
registered. The name's owner is never the one renamed, which is 正版优先 falling out
for free -- the identity source is never rewritten, so there is no policy to encode
and no 30-day hold to track.
The premium-name answer is cached asymmetrically, because the two directions have
very different costs. "Taken" is nearly permanent (Mojang does not recycle names) and
is trusted for a day; "free" can stop being true the moment someone buys that name,
and a stale "free" leaves a squatter holding a name its real owner has just bought,
so it is trusted for ten minutes. A lookup that fails with nothing cached fails
CLOSED -- assume premium, rename the third-party player: a Mojang outage must not
become an opportunity to hold someone else's name, and being wrong that way costs a
cosmetic prefix while being wrong the other way bounces the name's owner off the
proxy. The lookup gets its own 2s client rather than sharing the 5s auth client,
since it is a SECOND Mojang round-trip on a login that already spent one.
prefix is a required, unique, 1-4 character config field rather than something
derived from the tag, because it is player-visible and no derivation can know that
"littleskin" is meant to read LS. Two sources sharing a prefix would rewrite their
same-named players onto one name, so uniqueness is enforced case-insensitively --
the proxy folds case, and LS/ls would collide there while reading as distinct here.
Also close a pre-existing hole on the path this touches: a third-party source's
profile name was relayed verbatim, so a hostile or sloppy Yggdrasil root could put
"§4admin", an empty string, or 200 characters straight into the proxy's player list.
The name is now checked against the Minecraft username charset and a bad one is a 204,
the same way a bad UUID already was.
Verified end to end on the deploy host (Velocity 3.5.1 + Paper 26.2), both branches:
premium FLYEMOJ1 -> 195fadbd-f72e-4b9b-9f8f-f92586fe16ad, name unchanged
LittleSkin FLYEMOJ1 -> LS_FLYEMOJ1, f1b7b6ae-f250-348a-b069-a2ec0fcae668
both online at once, zero "already connected" rejections
LittleSkin FelisNyaTest01 -> joins as FelisNyaTest01, no prefix, UUID still v3
The last line is the one that matters: an ordinary third-party player collides with
nobody and keeps their name, while the rewrite that keeps identities apart still ran.
Paper's "LS_FLYEMOJ1 (formerly known as li_FLYEMOJ1) joined the game" is the other
half of it -- the rename moved the player's display name and their playerdata came
along untouched, because every server-side key is the UUID and the UUID does not
depend on the name.
Known ceiling, left alone deliberately: two players of one source whose names agree
on their first 16-len(prefix)-1 characters truncate onto the same in-game name, and a
prefixed name may itself happen to be a premium name. Both cost an "already connected"
bounce, not an identity -- the UUID rewrite does not depend on the name at all.
BREAKING CHANGE: every [[auth_source]] now requires prefix = "XX" (1-4 letters or
digits, unique across sources). An existing nano felis.toml without it fails to load
with an error naming the field, rather than silently keeping the collision.
d417efc got this backwards, in both the code comment and the installer summary.
It claimed authlib appends /session/minecraft/hasJoined itself, so the property
should be given the base URL only. Velocity does not work that way, and a real
login says so: pointed at http://127.0.0.1:8081, a Mojang login arrives at nano
as
GET /?username=FLYEMOJ1&serverId=-23ae0b50...
with no path at all. Velocity appends the query string to the property verbatim
and issues the request itself; authlib is not in the loop. nano has no route on
/, so it answers 404 and Velocity kicks the player with authservers_down.
Velocity's own default for the property is the full URL,
https://sessionserver.mojang.com/session/minecraft/hasJoined, which is the same
thing said another way.
With the full endpoint URL the same account logs straight in, so both the
nano.go header and summary_nano now print
-Dmojang.sessionserver=http://127.0.0.1:8081/session/minecraft/hasJoined
and note that the flag belongs between `java` and `-jar`.
Verified against Velocity 3.5.1 + Paper 26.2 on the deploy host: a Mojang login
reaches the backend with its real Mojang UUID unchanged, and a LittleSkin login
under the same username reaches it as UUIDv3(felisAuthNS, "littleskin:"+id) --
two different players on the backend, which is the point.
Deploying `felis nano` to a real Rocky Linux 10 host surfaced four defects that
no local check could see. Fixed together because they all sit on the same path
from `curl|bash` to a running felis-nano.service.
* docker killed the nano install on EL10. `acquire_nano_binary` pulled in
docker purely to build the binary; on Rocky 10.2 the docker-ce el10 rpms
install but dockerd refuses to start, so the install died at
`systemctl enable --now docker`. nano needs one static binary, not an image,
so the docker dependency is gone: fetch_source -> install_go_toolchain
(pinned FELIS_GO_VERSION, default 1.26.4, amd64/arm64) -> build_nano_binary.
* the built binary could not be exec'd by systemd (203/EXEC). The Go linker
renames its output out of $TMPDIR, and a same-filesystem rename carries the
source SELinux label, so `go build -o /usr/local/bin/felis` produced a binary
labelled user_tmp_t rather than bin_t. root is unconfined and could run it by
hand, which is what made this look fine, but the DynamicUser service could
not. build_nano_binary now stages the output and installs it as a fresh file
so the policy type transition labels it bin_t, with restorecon as a belt.
* re-running the installer did not converge. `systemctl enable --now` is a
no-op on an already-active unit, so a rebuilt binary was installed while the
old process kept running. Now enable + restart.
* the Velocity wiring comment in cmd/felis/nano.go was wrong. authlib appends
/session/minecraft/hasJoined itself, so -Dmojang.sessionserver takes the base
URL only, as the installer has always printed.
Also bind to loopback by default. hasJoined is unauthenticated by protocol --
authlib speaks the vanilla sessionserver dialect and sends no token -- so a
public bind is an open auth relay: anyone can point their own proxy at it and
spend this host's egress IP on Mojang until Mojang rate-limits it and the
operator's own players stop getting in. It is not an identity bypass (a caller
still needs a serverId hash bound to their own server key, which the upstream
Yggdrasil validates), but it is someone else's traffic on your address.
FELIS_NANO_LISTEN and the -listen flag now default to 127.0.0.1:8081, which a
same-host Velocity reaches unchanged; serving an off-host proxy is an explicit
opt-in. configure_nano_firewall no longer opens a port for a loopback bind, and
summary_nano prints the real bind address plus the relay warning.
Verified on the target host: installs with no docker present, service active,
binary labelled bin_t, `ss` shows LISTEN 127.0.0.1:8081, an external request is
unreachable, and an in-host request returns 204 with the login logged.
BREAKING CHANGE: felis nano defaults to 127.0.0.1:8081 instead of 0.0.0.0:8081.
A Velocity proxy on another machine must now set FELIS_NANO_LISTEN (or -listen)
to a reachable address, and should allow that port only from the proxy's IP.
bootstrap.sh now asks up front whether to install the full Felis control
plane or only Felis-nano, and grows a parallel install path for the
nano-only case.
- prompt_install_mode() runs right after OS detection and reads /dev/tty
(so it works under `curl ... | sudo bash`) offering [1] Felis / [2]
Felis-nano, default full. FELIS_INSTALL_MODE=full|nano skips the prompt
for non-interactive runs; no tty falls back to full.
- main_nano() installs only what nano needs: the felis binary (reusing
the embedded-binary / docker-build acquisition), a template felis.toml
carrying a commented [[auth_source]] example (Mojang-only until edited),
a felis-nano.service unit running `felis nano -config ... -listen ...`
under DynamicUser hardening, and a firewalld port-open for the listen
port. None of the k3s / Postgres / migrate / bundle steps run.
- write_nano_config is idempotent (leaves any existing config untouched)
and its template is valid as-is. summary_nano prints the hasJoined
endpoint and the Velocity -Dmojang.sessionserver flag, offering the
127.0.0.1 form when the proxy is on the same host.
Verified on WSL: `bash -n` clean; the emitted template loads via
config.LoadNano and the exact systemd ExecStart command serves 204 on a
miss ("Mojang + 0 third-party source(s)"); a duplicate-tag config still
exits non-zero citing "unique". Not exercised: a full main_nano run,
systemd activation of the unit, and shellcheck (unavailable in this env).
The login limbo pod dials FELIS_API_BASE_URL = felis-api.<ns>.svc:8081 (the
internal face, service-token auth) to mint bind codes and poll link status, but
the only Service named felis-api is the external NodePort face and declares only
port 443. A Service answers only on its declared ports, so felis-api:8081 had no
backend and every login-pod internal call silently failed to connect.
Render a separate ClusterIP Service felis-api-internal for port 8081 and repoint
InternalAPIBaseURL at it. A second port on the NodePort Service is not an option:
Type=NodePort allocates a node port for every declared port with no per-port
opt-out, so it would publish the no-Zero-Trust internal face on every node's
external IP. A distinct ClusterIP Service keeps 8081 in-cluster only, reachable
by the login pod via DNS and by the on-node break-glass console via the
ClusterIP (exported as APIInternalServiceName / APIInternalPort).
Manifest-level fix; the live packet path is pending real-cluster verification.
demo-up.sh collapses bootstrap -> build+import the limbo/lobby images -> wire [velocity] login_image/lobby_image into felis.host.toml -> felis setup into a single command, ending in the interactive Owner-creation TUI (the only step it cannot automate). Prefers prebuilt tars under deploy/images, else builds on the host, auto-resolving the LOOHP/Limbo CI jar and the latest stable Paper jar (all overridable by env); SKIP_BOOTSTRAP/SKIP_SETUP toggles for reruns.
The lobby image had never been built and two defects blocked it: the felis image .dockerignore excluded plugins/* and only re-included limbo/shared, so the lobby Dockerfile's COPY plugins/paper landed empty; and the plugin stage used eclipse-temurin:21-jdk, which ships no gradle (and the tree vendors no wrapper), failing with 'gradle: not found'. Re-include plugins/paper and build the paper plugin on gradle:8.14-jdk21, matching the limbo image. Verified: both images build and boot (limbo /healthz 200 on 25565; lobby reaches 'Done' with felis-paper enabled).
deploy/limbo assembles LOOHP/Limbo from its loose CI artifacts plus the felis-limbo plugin (and the shared link core), with an entrypoint that pins server-port to the operator's GamePort (25565) on every start. deploy/lobby carries the Paper + felis-paper hub image. .dockerignore re-includes plugins/limbo and plugins/shared so the plugin image build sees them.
StartupSpec.HealthHTTPPort/Path switch pod readiness from plain-TCP to an HTTP GET for RCON-less loaders (LOOHP/Limbo) that report 'started' only after the first tick. User servers now default FallbackServer to the login gate, never the lobby, so a stopped/starting backend keeps authentication in front of a fresh connection.
Wire the fourth mandated §23 metric to a real producer. The histogram
spans two reconcile passes, so anchor and observation must persist in
status:
- Add status.startRequestedAt, set once on the first Starting reconcile
of a start attempt and cleared on Stopped so the next start re-anchors.
- Observe felis_start_duration_seconds exactly when readiness is first
reached (ReadySignalAt - StartRequestedAt), guarded so a server that
reaches ready without a Starting pass records nothing.
- Mirror the field into the deepcopy and the structural CRD schema so the
apiserver does not prune it on patchStatus round-trips.
- Promote prometheus/client_golang and client_model to direct deps now
that the operator and its tests import them.
Tests drive a step clock through Starting -> Running asserting the exact
observed duration, and through Running -> Stopped asserting the metric is
observed once and the anchor clears.
bootstrap.sh auto-detects the host package manager (apt/dnf) and installs whatever is missing: Docker, k3s, and PostgreSQL. It builds and imports the felis image, opens pg_hba to the pod CIDR, runs migrations, and applies the rendered control-plane bundle, leaving Web disabled pending 'felis setup'. The Dockerfile builds the distroless felis image; deploy/crd holds the MinecraftServer CRD.
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