The script that sets the SSH, PAM, pwquality and auditd baseline on twelve
containers existed only as a root-owned copy on the machines it hardens.
Bring it into the repo so a change reaches one place instead of twelve.
Two substantive changes over the copy that shipped on 2026-07-24:
- Deny forwarding per option instead of via DisableForwarding. Same effect,
but DisableForwarding overrides every other forwarding option and is
invisible in sshd -T, which makes a rejected port-forward read as a
configuration that should work.
- Quote the command substitution in MODDIR (SC2046).
The header and README now record the rollout command, the containers left
unhardened as break-glass foundation, and why host-specific exceptions must
live in a drop-in that sorts after 99-cis-hardening.conf.
Both from the cross-review, both fair.
"Go setzt CGO_ENABLED=0" is right about the effect and wrong about the
mechanism: Go does not set the variable, cgo simply stays off when no C
compiler is found, and go env then reports 0. Reworded.
And protoc on an instance-wide runner ties every repository to the
distribution's version -- 3.21.x on Debian 12. Unlike make and gcc that is a
code generator, so a distro upgrade changes generated code for all users at
once. The comment says so now, and says where a project that needs its own
version should pin it instead of raising it here for everybody.
The runner is host-mode, so there is no image bringing tools along: what is
not on this LXC, no job has. Measured on l.kirchner/patchmgr, a Go project,
where all six CI jobs were assigned and every one of them died in the first
seconds:
make all make: command not found
go test -race go: -race requires cgo; enable cgo by setting CGO_ENABLED=1
make proto sudo: command not found
Four packages, each for a reason:
make the gate commands are make targets
gcc Go turns CGO_ENABLED off when it finds no C compiler,
and the race detector cannot be built without cgo
protobuf-compiler protoc itself
libprotobuf-dev the well-known .proto includes under
/usr/include/google/protobuf; without them protoc fails
even though the binary is there
sudo stays absent on purpose. A workflow must not be able to install anything
on this runner -- what is needed is declared here, in the script, and not in
somebody's pipeline. That also keeps the security note at the top of this file
honest: the LXC owns nothing, and it gains nothing at a workflow's request.
Go is not in the list. Projects fetch it through actions/setup-go, because CI
matrices run more than one version.
Applied to the running LXC (301 on pve-gamer) while the runner was idle, then
verified: make 4.3, gcc 12.2.0, libprotoc 3.21.12, 11 .proto includes present.
The service PATH already contains /usr/bin, so no restart was needed.
- assert encoding BEFORE role/password mutation on re-run, so an old
SQL_ASCII DB aborts with no side effects (codex finding 1)
- ensure_utf8_locale_active honours its locale argument consistently in
match, locale.gen line and export (codex finding 2)
- assert_db_encoding_utf8 uses argv-clean runuser psql with :'db' literal
binding instead of nested su -c shell; docs keep su - postgres -c
(codex finding 3)
A PostgreSQL cluster/database freezes its encoding at initdb / CREATE
DATABASE time; a C (non-UTF-8) locale yields a SQL_ASCII cluster, which
makes psycopg3 return bytes and crashes SQLAlchemy. Harden the installer
and add a reusable pattern for future DB installers:
- ensure_utf8_locale_active: generate AND activate en_US.UTF-8 for the
install process before the server package runs initdb; abort if the
locale is not actually available
- create the database explicitly with TEMPLATE template0 ENCODING 'UTF8'
LC_COLLATE/LC_CTYPE 'en_US.UTF-8' instead of inheriting the cluster
default
- assert_db_encoding_utf8: post-install guard, abort with an actionable
message if pg_encoding_to_char is not UTF8 (catches old SQL_ASCII DBs
on re-run too)
- credentials/README docs use su - postgres -c (minimal LXCs have no sudo)
prompt_lxc_config asks 'SSH-Root-Login erlauben? [Y/n]' (env-presettable
via SSH_ROOT_LOGIN, validated, normalized to yes|no). The bootstrap passes
the value into the container; configure_ssh_root_login writes
/etc/ssh/sshd_config.d/zz-root-login.conf (yes -> PermitRootLogin yes,
no -> prohibit-password) and reloads sshd.
- source build.func (script was unrunnable without it)
- validate DB_NAME/DB_USER/DB_PORT/NEXUS_APP_IP before SQL/pg_hba use
- rotate password when role exists but credentials file is missing
webapp-pattern ct/install pair: PGDG repo, database nexus with
least-privilege owner role, pg_hba allowlist restricted to the nexus
app LXC (explicit reject for everything else), pgvector created by the
installer, credentials/DSN summary in /root/nexus-db.credentials.
Idempotent re-runs keep role/db and do not rotate the password.
A reboot before the first deploy would leave the enabled unit in failed
state; the condition keeps it inert until start.sh exists (same guard as
nexus-worker.service).
- new install/nexus-runtime.sh (idempotent, re-runnable on an existing
LXC): uv for the nexus user (manages Python 3.12), tesseract deu+eng,
nexus-worker.service unit (ConditionPathExists guards the skeleton
phase), sudoers extended to cover the worker service
- nexus-install.sh: RUNTIME section now invokes nexus-runtime.sh at the
end of the install (after base sudoers/units, which it extends)
Installs Node.js and act_runner in host mode, registers the runner as
the unprivileged webapp user, and wires up systemd units for the runner
and the next-start service. A narrow sudoers rule lets the runner restart
only webapp.service; the build/deploy itself is driven by the repo workflow.
claude-bot
l.kirchner