Pulls the 5 privileged helpers out of deploy/files/usr/local/{libexec,sbin}/
into top-level scripts/{libexec,sbin}/. They are application-inherent code
(invoked at runtime via sudo from l4d2host/l4d2web), not deploy artifacts —
the previous nesting under deploy/files/ confused source-of-truth with
install-target FHS layout.
deploy/ now means "reference exemplar": README explaining the target
layout, plus example sudoers / sysctl / sandbox-resolv.conf / env
templates / curated systemd units (the ones ckn-bw's reactor emits).
Anyone building a fresh deployment (other than ckn-bw) reads this tree.
Dead static artifacts deleted: left4me-apply-cake helper, left4me-cake
+ left4me-nft-mark service units, cake.env, left4me-mark.nft, and the
superseded deploy-test-server.sh installer.
Tests split to match the new shape:
- scripts/tests/{test_overlay,test_script_sandbox,test_systemctl_helper,
test_journalctl_helper,test_helpers_use_fixed_paths,test_sudoers_grants}.py
with shared fixtures in conftest.py
- deploy/tests/test_example_units.py (renamed from test_deploy_artifacts.py)
— slimmed to lock down the curated example units, sysctl, env templates
l4d2host/tests/test_overlay_helper.py: helper-source path updated to
scripts/libexec/left4me-overlay (was building the path segment-by-segment
under deploy/files/, missed by the path-prefix grep during pre-flight).
Runtime install-target paths (/usr/local/{libexec,sbin}/) unchanged, so
l4d2host/service_control.py, l4d2web/services/overlay_builders.py, the
sudoers grants, and the systemd units all keep their existing path
references.
Requires the matching ckn-bw change to bundles/left4me/items.py
(install_left4me_scripts repointed from /opt/left4me/src/deploy/files/...
to /opt/left4me/src/scripts/...). Left4me lands first so a fresh
git_deploy exposes the new source path before the bundle apply runs.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds IPAddressDeny= to the sandbox unit covering loopback (127/8 + ::1),
link-local (169.254/16 + fe80::/10), multicast (224/4 + ff00::/8), all
RFC1918 v4 (10/8, 172.16/12, 192.168/16), CGNAT (100.64/10), and ULA v6
(fc00::/7). The kernel attaches systemd's sd_fw_egress BPF program to
the unit's cgroup; egress packets matching any of the deny prefixes are
silently dropped at the cgroup boundary.
Important: do NOT pair this with `IPAddressAllow=any`. Documentation
claims "more specific rule wins" but on this systemd 257 + kernel 6.12
combo, having both set causes the allow to win unconditionally — the
deny gets ignored. Empty IPAddressAllow + populated IPAddressDeny is the
correct shape: kernel default "allow all" applies to non-listed
addresses, and the listed prefixes are blocked.
Because the host's resolv.conf typically points at a private-IP DNS
server (10.0.0.1 in the test deploy), blocking RFC1918 also kills DNS.
Adds a static /etc/left4me/sandbox-resolv.conf with public resolvers
(Cloudflare 1.1.1.1, Google 8.8.8.8) and bind-mounts that into the
sandbox at /etc/resolv.conf, replacing the host's resolver inside the
sandbox only.
Smoke-tested on ckn@10.0.4.128:
- public 1.1.1.1:443: CONNECTED
- public HTTPS via DNS (steamcommunity.com): 200
- localhost web app 127.0.0.1:8000: blocked (TimeoutError)
- localhost sshd 127.0.0.1:22: blocked
- private LAN ssh 10.0.4.128:22: blocked
- private DNS 10.0.0.1:53: blocked
AF_UNIX stays in RestrictAddressFamilies — dropping it would risk
breaking NSS / syslog for marginal gain, and the IP-level filter
addresses the primary threat (reaching the host's HTTP/SSH services).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
