Elden Ring under Proton on Linux is the same Windows binary, so every
AOB signature and memory offset is unchanged — only how the process
gets found and read differs. Split main.go/i18n.go (previously
Windows-only) into a portable process.go (signature scanning, pointer
resolution, the poll loop) plus process_windows.go/process_linux.go
behind a small boundary: findProcessID, openProcess,
closeProcessHandle, readMemory, findModuleBase, productVersion,
systemLang.
Linux side: finds the process by walking /proc/*/maps for a mapping
ending in eldenring.exe (Proton runs several helper processes, so
matching by name alone isn't reliable), reads memory via
/proc/<pid>/mem (stdlib only, no external deps), and has no
productVersion equivalent (returns ok=false — this was always just a
hint for which PlayerIns offset to try first; the real one is
confirmed by a live memory read regardless). openProcess probes
/proc/<pid>/mem up front so a ptrace_scope permission failure surfaces
immediately with the exact `sudo setcap cap_sys_ptrace+ep <path>` fix,
never suggesting the system-wide ptrace_scope=0 weakening or running
as root.
main.go and i18n.go are fully portable now, no build tags. Verified:
Windows build/vet/test plus a real run (no regression from moving
~500 lines). Linux is cross-compile build/vet only in this session —
not yet run against a real Proton process.
The co-op link was authenticated (HMAC token, never sent over the wire)
but not encrypted. The hub now generates a self-signed cert on first run;
the peer pins its exact fingerprint (no CA involved — there isn't one for
a Tailscale/LAN address), delivered via a single invite-code paste that
also carries the token, replacing today's separate IP+token copy.
The peer link moves to its own TLS-only port (peer_listen, 47823) so the
plain overlay/panel port (47822, OBS-facing) never needs to be exposed
alongside it — today, opening the overlay port to a remote partner also
exposes /deaths and the panel to anyone.
Mandatory pinning, no insecure fallback: a half-configured peer (some but
not all of hub/token/fingerprint, or a broken invite) fails loudly at
startup rather than connecting unpinned. An unconfigured peer still runs
fine as a local-only overlay, same as before.
New: tlscert.go (cert generation/persistence), pin.go (fingerprint
pinning), invite.go (invite-code encode/decode, host auto-detection),
each with tests. main.go/config.go/duo.go/ws.go carry the wiring for
this — the dual listener, new config keys, and the TLS-aware WebSocket
dial — and were rewritten in English in the process, per the project's
new English-only code convention (see CLAUDE.md).
Reads the game's process memory read-only (AOB signature scanning,
re-resolved every tick — never a cached pointer) and serves a live
death counter as a browser-source overlay plus a status panel.
Supports co-op: each player runs the program locally, one acts as
hub. The peer link is authenticated (HMAC challenge/response, no
token on the wire, constant-time compare) but not yet encrypted —
see CLAUDE.md's TODO section for the planned TLS+pinning split.
Zero external dependencies — including a hand-rolled WebSocket
implementation — so the whole thing ships as one .exe.
emmatherock