# felhom-agent sudoers allowlist — the NARROW host-root surface (slice 5 Phase B, doc 03 §3/§7). # # Install as a drop-in: /etc/sudoers.d/felhom-agent (mode 0440, root:root), validated with # `visudo -cf`. The agent runs as the non-root `felhom-agent` service user and shells out via # `sudo -n` with FIXED argument vectors (no shell). The fine-grained validation is done IN # the agent BEFORE exec (internal/storage/validate.go): UUIDs against a strict hex regex, # mount paths confined+traversal-checked, SMART devices whitelisted to raw disks, LVM names # charset-checked. These sudoers wildcards are the COARSE allowlist; the agent is the fine # gate, so a wildcard can never be abused by a value the agent didn't already validate. # # Binary paths MUST match the agent config (privileged.systemctl/install/smartctl/lvs). Adjust # for your distro (Debian/PVE shown). A missing/declined entry degrades the agent with a # warning (SMART→UNKNOWN, mount→logged error), it does not crash. Cmnd_Alias FELHOM_MOUNT = \ /usr/bin/install -o root -g root -m 0644 -- /var/lib/felhom-agent/units/* /etc/systemd/system/*.mount, \ /usr/bin/systemctl daemon-reload, \ /usr/bin/systemctl enable --now -- *.mount, \ /usr/bin/systemctl disable -- *.mount, \ /usr/bin/systemctl stop -- *.mount Cmnd_Alias FELHOM_DISK = \ /usr/sbin/smartctl -a -j /dev/sd[a-z]*, \ /usr/sbin/smartctl -a -j /dev/nvme[0-9]*n[0-9]*, \ /usr/sbin/smartctl -a -j /dev/vd[a-z]*, \ /usr/sbin/smartctl -a -j /dev/hd[a-z]*, \ /usr/sbin/lvs --reportformat json --units b -o lv_name\,data_percent\,metadata_percent -- *, \ /usr/sbin/pvs --reportformat json --noheadings -o pv_name, \ /usr/sbin/zpool status -P # Provisioning back-half (slice 8A, doc 03 §6): populate a guest's bootstrap config mount # host-side (internal/provision). These are host-root ops the API token cannot do — a bind mount # is root@pam-only, and the chown maps the 0600 bootstrap.json to the unprivileged-LXC guest-root # (uid/gid 100000, spike gotcha 1). The host dir is AGENT-OWNED state under /var/lib/felhom-agent/ # (the wildcard only ever names a path the agent itself created), and the bootstrap file the agent # writes there is the only thing these touch. ':' is escaped per sudoers grammar. Cmnd_Alias FELHOM_PROVISION = \ /usr/bin/chown -R 100000\:100000 /var/lib/felhom-agent/guests/*, \ /usr/sbin/pct set [0-9]* -mp[0-9]* /var/lib/felhom-agent/guests/*, \ /usr/sbin/pct set [0-9]* -onboot 1 # Disk inspection + format (slice 8C + Impl-1). blkid/lsblk read the device's data-bearing evidence # (the agent decides data-bearing-ness from THIS, never the caller's claim). Format goes ONLY through # felhom-mkfs-guarded (Impl-1 Part B): raw mkfs.* is NO LONGER allowlisted, so even a bad agent cannot # mkfs the OS disk — the wrapper re-checks the catastrophic cases (system disk / LVM PV / foreign mount) # as root and refuses, and the agent's unclaimed-disk filter (claim.go) is the primary guard above it. Cmnd_Alias FELHOM_FORMAT = \ /usr/sbin/blkid -p -o export /dev/*, \ /usr/bin/lsblk -J -o NAME\,FSTYPE\,PTTYPE\,MOUNTPOINT /dev/*, \ /usr/local/sbin/felhom-mkfs-guarded /dev/* * # LAN split-horizon resolver (internal/lanresolver): the agent manages a host-side dnsmasq that # answers *. with each guest's live LAN IP. install only ever writes felhom-*.conf # drop-ins (from agent-written /tmp temp files); the two `pct exec` reads are FIXED command vectors # (the guest's eth0 IPv4 + the controller's pulled controller.yaml for the domain) — NOT a general # `pct exec`. systemctl is scoped to the dnsmasq unit only. The agent never edits /etc/resolv.conf. Cmnd_Alias FELHOM_DNSMASQ = \ /usr/bin/apt-get install -y -q dnsmasq, \ /usr/bin/install -m 0644 /tmp/felhom-resolver-*.conf /etc/dnsmasq.d/felhom-*.conf, \ /usr/bin/systemctl enable --now dnsmasq, \ /usr/bin/systemctl reload dnsmasq, \ /usr/bin/systemctl restart dnsmasq, \ /usr/bin/rm -f /etc/dnsmasq.d/felhom-*.conf, \ /usr/sbin/pct exec [0-9]* -- ip -4 -o addr show dev eth0, \ /usr/sbin/pct exec [0-9]* -- docker exec felhom-controller cat /opt/docker/felhom-controller/controller.yaml # Guest mountpoint lifecycle (intermediary-mount re-architecture + C1 net). The pre-start self-heal hook # wrapper is installed once into the PVE snippets dir (from an agent-written /tmp file) and registered # per-guest; decommission/eject DELETE the dead mountpoint slot so a missing bind source can't brick the # guest at next boot (the B3 C1 fix). The agent fine-validates the vmid (numeric) + slot (mp[0-9]+) and # the snippet path is fixed — the wildcards are the coarse allowlist. The install SOURCE is a # random-named agent temp (os.CreateTemp, audit B1 — a fixed /tmp name was a local TOCTOU), hence the # glob; the DESTINATION stays pinned. The `mkdir -p` creates the snippets dir on a FRESH box — # `install` won't create parents, so without it the hook install failed silently on Day-0 boxes # (B2, DRILL-day0-cleanroom-2026-07-03; fixed agent v0.63.0). Cmnd_Alias FELHOM_GUESTHOOK = \ /usr/bin/mkdir -p /var/lib/vz/snippets, \ /usr/bin/install -m 0755 -- /tmp/felhom-guest-hook-*.sh /var/lib/vz/snippets/felhom-guest-hook.sh, \ /usr/sbin/pct set [0-9]* --hookscript local\:snippets/felhom-guest-hook.sh, \ /usr/sbin/pct set [0-9]* --delete mp[0-9]*, \ /usr/sbin/pct reboot [0-9]* # Intermediary mount model (the drive hot-swap re-architecture). The agent keeps a SHARED host parent # /mnt/felhom-drives (self-bind + make-shared + a boot-persistence systemd unit) and binds/unbinds each # drive's felhom-data namespace UNDERNEATH it so the change propagates into the running guest live (no # pct, no reboot). The agent fine-validates the drive name + confines paths before any exec; the trailing # `*` (matching the comma-laden mp spec) mirrors the existing FELHOM_PROVISION pattern. # `lxc-info -n -p -H` resolves the guest init PID for the GuestSeesMount / bound_under_parent check # (a READ — the drive-gate's "is the drive live in the guest?" signal); WITHOUT it the non-root agent gets # an empty PID and reports every drive absent (multi-drive flapping, audit 2026-06-29). `make-private` # isolates the parent's peer group on FIRST setup only (EnsureSharedParent guards on mountpoint, so it # never re-churns a live parent); without it the parent stays in root's group and submounts double. Cmnd_Alias FELHOM_INTERMEDIARY = \ /usr/bin/mkdir -p /mnt/felhom-drives, \ /usr/bin/mkdir -p /mnt/felhom-drives/*, \ /usr/bin/mkdir -p /mnt/*/felhom-data, \ /usr/bin/chown 100000\:100000 /mnt/*/felhom-data, \ /usr/bin/mount --bind /mnt/felhom-drives /mnt/felhom-drives, \ /usr/bin/mount --make-shared /mnt/felhom-drives, \ /usr/bin/mount --make-private /mnt/felhom-drives, \ /usr/bin/mount --bind /mnt/*/felhom-data /mnt/felhom-drives/*, \ /usr/bin/umount /mnt/felhom-drives/*, \ /usr/bin/install -m 0755 -- /tmp/felhom-shared-parent-*.sh /usr/local/sbin/felhom-shared-parent.sh, \ /usr/bin/install -m 0644 -- /tmp/felhom-shared-parent-*.service /etc/systemd/system/felhom-shared-parent.service, \ /usr/bin/systemctl enable felhom-shared-parent.service, \ /usr/bin/lxc-info -n [0-9]* -p -H, \ /usr/sbin/pct set [0-9]* -mp8 /mnt/felhom-drives* # Controller-swap / managed auto-update (Option A, non-root). The agent owns the in-guest controller # image SWAP (it survives the controller being killed mid-swap): read the baked image ref, check the # pre-pulled target is present, rewrite /etc/felhom-controller-image, restart the bootstrap unit, # health-check, roll back on failure. Each grant is bounded — NO general `pct exec` and NO `bash -c`: # cat — read the current image ref (read-only) # docker image inspect * — is the pre-pulled target present? (read-only) # docker inspect -f * — container running/health/image (read-only; `*` spans the -f template # + container across spaces, spike-confirmed) # systemctl restart — re-run the golden's bootstrap (the only state change) # tee — WRITE the ref; content is fed on STDIN (no shell, no interpolation), # the agent strict-validates the ref (controllerImageRe) before the write. # Validated GO: felhom.eu/documentation/audits/SPIKE-controllerswap-narrow-grants-2026-06-29.md. Cmnd_Alias FELHOM_CONTROLLERSWAP = \ /usr/sbin/pct exec [0-9]* -- cat /etc/felhom-controller-image, \ /usr/sbin/pct exec [0-9]* -- docker image inspect *, \ /usr/sbin/pct exec [0-9]* -- docker inspect -f *, \ /usr/sbin/pct exec [0-9]* -- systemctl restart felhom-controller-bootstrap.service, \ /usr/sbin/pct exec [0-9]* -- tee /etc/felhom-controller-image # Stale-lock recovery (F2-b, v0.49.0). A host reboot DURING a vzdump backup leaves the guest with a # `snapshot-delete`/`backup` lock + `onboot:1` then can't start it → the customer box stays DOWN. The # agent clears the STALE lock at startup (only when no vzdump is in-flight). `pct unlock` is the one op # with no API equivalent (snapshot-delete + start go through the API token); the agent fine-validates the # vmid (numeric) before exec — the `[0-9]*` is the coarse allowlist. Cmnd_Alias FELHOM_STALELOCK = \ /usr/sbin/pct unlock [0-9]* # Network storage / NAS (Part A1, SPIKE-nas-storage-2026-06-29). The agent mounts a customer NAS share # HOST-SIDE under /mnt/felhom-drives/ via a systemd .automount (+ .mount) pair so it propagates # into the guest through the existing shared bind (an unprivileged LXC cannot mount NFS/CIFS itself). # A NAS is NOT a drive — no durable-id, no SMART, no wipe; these grants only install/enable/remove the # unit pair. The agent fine-validates every value (share name, server, export, uid/gid, creds path) before # any unit is rendered (internal/storage/netmount.go ValidateNetworkMountSpec); the trailing globs are the # COARSE allowlist. The `.mount` install/enable/disable/stop reuse FELHOM_MOUNT; this alias adds the # `.automount` variants + the unit-file removal. The unit FILE name is the systemd-escaped mountpoint, # which always begins `mnt-felhom` (the mountpoint is /mnt/felhom-drives/), so the rm glob is scoped # to felhom mount units only. mkdir of the mountpoint reuses FELHOM_INTERMEDIARY's /mnt/felhom-drives/*. Cmnd_Alias FELHOM_NETMOUNT = \ /usr/bin/install -o root -g root -m 0644 -- /var/lib/felhom-agent/units/* /etc/systemd/system/*.automount, \ /usr/bin/systemctl enable --now -- *.automount, \ /usr/bin/systemctl disable -- *.automount, \ /usr/bin/systemctl stop -- *.automount, \ /usr/bin/rm -f /etc/systemd/system/mnt-felhom* # Offsite WG tunnel (S3, doc 06 §3.3). The agent manages wg-quick@wg-felhom as an agent-managed # host service (the dnsmasq/lanresolver shape): conf staged in the agent-owned StateDir (never # /tmp), installed 0600 to the FIXED destination, unit enable/restart/disable. The ONLY wg read # is `latest-handshakes` — `wg show dump` is FORBIDDEN everywhere (its interface line # carries the PRIVATE KEY; the S1 session-log incident). Both install paths are FIXED (no glob): # the agent has exactly one tunnel conf to manage. Cmnd_Alias FELHOM_WG = \ /usr/bin/apt-get install -y -q wireguard-tools, \ /usr/bin/install -o root -g root -m 0600 -- /var/lib/felhom-agent/wg/wg-felhom.conf /etc/wireguard/wg-felhom.conf, \ /usr/bin/systemctl enable --now wg-quick@wg-felhom, \ /usr/bin/systemctl restart wg-quick@wg-felhom, \ /usr/bin/systemctl disable --now wg-quick@wg-felhom, \ /usr/bin/wg show wg-felhom latest-handshakes felhom-agent ALL=(root) NOPASSWD: FELHOM_MOUNT, FELHOM_DISK, FELHOM_PROVISION, FELHOM_FORMAT, FELHOM_DNSMASQ, FELHOM_GUESTHOOK, FELHOM_INTERMEDIARY, FELHOM_CONTROLLERSWAP, FELHOM_STALELOCK, FELHOM_NETMOUNT, FELHOM_WG